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path: root/drivers/tty/serial/8250/8250_port.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_port.c')
-rw-r--r--drivers/tty/serial/8250/8250_port.c1701
1 files changed, 811 insertions, 890 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 2abb3de11a48..719faf92aa8a 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -15,6 +15,7 @@
#include <linux/moduleparam.h>
#include <linux/ioport.h>
#include <linux/init.h>
+#include <linux/irq.h>
#include <linux/console.h>
#include <linux/gpio/consumer.h>
#include <linux/sysrq.h>
@@ -37,21 +38,6 @@
#include "8250.h"
-/* Nuvoton NPCM timeout register */
-#define UART_NPCM_TOR 7
-#define UART_NPCM_TOIE BIT(7) /* Timeout Interrupt Enable */
-
-/*
- * Debugging.
- */
-#if 0
-#define DEBUG_AUTOCONF(fmt...) printk(fmt)
-#else
-#define DEBUG_AUTOCONF(fmt...) do { } while (0)
-#endif
-
-#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
-
/*
* Here we define the default xmit fifo size used for each type of UART.
*/
@@ -171,13 +157,6 @@ static const struct serial8250_config uart_config[] = {
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
.flags = UART_CAP_FIFO,
},
- [PORT_AR7] = {
- .name = "AR7",
- .fifo_size = 16,
- .tx_loadsz = 16,
- .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00,
- .flags = UART_CAP_FIFO /* | UART_CAP_AFE */,
- },
[PORT_U6_16550A] = {
.name = "U6_16550A",
.fifo_size = 64,
@@ -263,7 +242,7 @@ static const struct serial8250_config uart_config[] = {
.tx_loadsz = 63,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
UART_FCR7_64BYTE,
- .flags = UART_CAP_FIFO,
+ .flags = UART_CAP_FIFO | UART_CAP_NOTEMT,
},
[PORT_RT2880] = {
.name = "Palmchip BK-3103",
@@ -307,10 +286,34 @@ static const struct serial8250_config uart_config[] = {
.rxtrig_bytes = {1, 32, 64, 112},
.flags = UART_CAP_FIFO | UART_CAP_SLEEP,
},
+ [PORT_ASPEED_VUART] = {
+ .name = "ASPEED VUART",
+ .fifo_size = 16,
+ .tx_loadsz = 16,
+ .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00,
+ .rxtrig_bytes = {1, 4, 8, 14},
+ .flags = UART_CAP_FIFO,
+ },
+ [PORT_MCHP16550A] = {
+ .name = "MCHP16550A",
+ .fifo_size = 256,
+ .tx_loadsz = 256,
+ .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01,
+ .rxtrig_bytes = {2, 66, 130, 194},
+ .flags = UART_CAP_FIFO,
+ },
+ [PORT_BCM7271] = {
+ .name = "Broadcom BCM7271 UART",
+ .fifo_size = 32,
+ .tx_loadsz = 32,
+ .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01,
+ .rxtrig_bytes = {1, 8, 16, 30},
+ .flags = UART_CAP_FIFO | UART_CAP_AFE,
+ },
};
/* Uart divisor latch read */
-static int default_serial_dl_read(struct uart_8250_port *up)
+static u32 default_serial_dl_read(struct uart_8250_port *up)
{
/* Assign these in pieces to truncate any bits above 7. */
unsigned char dll = serial_in(up, UART_DLL);
@@ -320,143 +323,97 @@ static int default_serial_dl_read(struct uart_8250_port *up)
}
/* Uart divisor latch write */
-static void default_serial_dl_write(struct uart_8250_port *up, int value)
+static void default_serial_dl_write(struct uart_8250_port *up, u32 value)
{
serial_out(up, UART_DLL, value & 0xff);
serial_out(up, UART_DLM, value >> 8 & 0xff);
}
-#ifdef CONFIG_SERIAL_8250_RT288X
-
-/* Au1x00/RT288x UART hardware has a weird register layout */
-static const s8 au_io_in_map[8] = {
- 0, /* UART_RX */
- 2, /* UART_IER */
- 3, /* UART_IIR */
- 5, /* UART_LCR */
- 6, /* UART_MCR */
- 7, /* UART_LSR */
- 8, /* UART_MSR */
- -1, /* UART_SCR (unmapped) */
-};
-
-static const s8 au_io_out_map[8] = {
- 1, /* UART_TX */
- 2, /* UART_IER */
- 4, /* UART_FCR */
- 5, /* UART_LCR */
- 6, /* UART_MCR */
- -1, /* UART_LSR (unmapped) */
- -1, /* UART_MSR (unmapped) */
- -1, /* UART_SCR (unmapped) */
-};
-
-unsigned int au_serial_in(struct uart_port *p, int offset)
-{
- if (offset >= ARRAY_SIZE(au_io_in_map))
- return UINT_MAX;
- offset = au_io_in_map[offset];
- if (offset < 0)
- return UINT_MAX;
- return __raw_readl(p->membase + (offset << p->regshift));
-}
-
-void au_serial_out(struct uart_port *p, int offset, int value)
-{
- if (offset >= ARRAY_SIZE(au_io_out_map))
- return;
- offset = au_io_out_map[offset];
- if (offset < 0)
- return;
- __raw_writel(value, p->membase + (offset << p->regshift));
-}
-
-/* Au1x00 haven't got a standard divisor latch */
-static int au_serial_dl_read(struct uart_8250_port *up)
-{
- return __raw_readl(up->port.membase + 0x28);
-}
-
-static void au_serial_dl_write(struct uart_8250_port *up, int value)
-{
- __raw_writel(value, up->port.membase + 0x28);
-}
-
-#endif
-
-static unsigned int hub6_serial_in(struct uart_port *p, int offset)
+#ifdef CONFIG_HAS_IOPORT
+static u32 hub6_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
outb(p->hub6 - 1 + offset, p->iobase);
return inb(p->iobase + 1);
}
-static void hub6_serial_out(struct uart_port *p, int offset, int value)
+static void hub6_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
outb(p->hub6 - 1 + offset, p->iobase);
outb(value, p->iobase + 1);
}
+#endif /* CONFIG_HAS_IOPORT */
-static unsigned int mem_serial_in(struct uart_port *p, int offset)
+static u32 mem_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readb(p->membase + offset);
}
-static void mem_serial_out(struct uart_port *p, int offset, int value)
+static void mem_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writeb(value, p->membase + offset);
}
-static void mem16_serial_out(struct uart_port *p, int offset, int value)
+static void mem16_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writew(value, p->membase + offset);
}
-static unsigned int mem16_serial_in(struct uart_port *p, int offset)
+static u32 mem16_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readw(p->membase + offset);
}
-static void mem32_serial_out(struct uart_port *p, int offset, int value)
+static void mem32_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writel(value, p->membase + offset);
}
-static unsigned int mem32_serial_in(struct uart_port *p, int offset)
+static u32 mem32_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readl(p->membase + offset);
}
-static void mem32be_serial_out(struct uart_port *p, int offset, int value)
+static void mem32be_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
iowrite32be(value, p->membase + offset);
}
-static unsigned int mem32be_serial_in(struct uart_port *p, int offset)
+static u32 mem32be_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return ioread32be(p->membase + offset);
}
-static unsigned int io_serial_in(struct uart_port *p, int offset)
+#ifdef CONFIG_HAS_IOPORT
+static u32 io_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return inb(p->iobase + offset);
}
-static void io_serial_out(struct uart_port *p, int offset, int value)
+static void io_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
outb(value, p->iobase + offset);
}
+#endif
+static u32 no_serial_in(struct uart_port *p, unsigned int offset)
+{
+ return ~0U;
+}
+
+static void no_serial_out(struct uart_port *p, unsigned int offset, u32 value)
+{
+}
static int serial8250_default_handle_irq(struct uart_port *port);
@@ -468,10 +425,12 @@ static void set_io_from_upio(struct uart_port *p)
up->dl_write = default_serial_dl_write;
switch (p->iotype) {
+#ifdef CONFIG_HAS_IOPORT
case UPIO_HUB6:
p->serial_in = hub6_serial_in;
p->serial_out = hub6_serial_out;
break;
+#endif
case UPIO_MEM:
p->serial_in = mem_serial_in;
@@ -492,20 +451,17 @@ static void set_io_from_upio(struct uart_port *p)
p->serial_in = mem32be_serial_in;
p->serial_out = mem32be_serial_out;
break;
-
-#ifdef CONFIG_SERIAL_8250_RT288X
- case UPIO_AU:
- p->serial_in = au_serial_in;
- p->serial_out = au_serial_out;
- up->dl_read = au_serial_dl_read;
- up->dl_write = au_serial_dl_write;
- break;
-#endif
-
- default:
+#ifdef CONFIG_HAS_IOPORT
+ case UPIO_PORT:
p->serial_in = io_serial_in;
p->serial_out = io_serial_out;
break;
+#endif
+ default:
+ WARN(p->iotype != UPIO_PORT || p->iobase,
+ "Unsupported UART type %x\n", p->iotype);
+ p->serial_in = no_serial_in;
+ p->serial_out = no_serial_out;
}
/* Remember loaded iotype */
up->cur_iotype = p->iotype;
@@ -530,27 +486,6 @@ serial_port_out_sync(struct uart_port *p, int offset, int value)
}
/*
- * For the 16C950
- */
-static void serial_icr_write(struct uart_8250_port *up, int offset, int value)
-{
- serial_out(up, UART_SCR, offset);
- serial_out(up, UART_ICR, value);
-}
-
-static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
-{
- unsigned int value;
-
- serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
- serial_out(up, UART_SCR, offset);
- value = serial_in(up, UART_ICR);
- serial_icr_write(up, UART_ACR, up->acr);
-
- return value;
-}
-
-/*
* FIFO support.
*/
static void serial8250_clear_fifos(struct uart_8250_port *p)
@@ -612,24 +547,27 @@ EXPORT_SYMBOL_GPL(serial8250_rpm_put);
*/
static int serial8250_em485_init(struct uart_8250_port *p)
{
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&p->port.lock);
+
if (p->em485)
- return 0;
+ goto deassert_rts;
p->em485 = kmalloc(sizeof(struct uart_8250_em485), GFP_ATOMIC);
if (!p->em485)
return -ENOMEM;
- hrtimer_init(&p->em485->stop_tx_timer, CLOCK_MONOTONIC,
- HRTIMER_MODE_REL);
- hrtimer_init(&p->em485->start_tx_timer, CLOCK_MONOTONIC,
- HRTIMER_MODE_REL);
- p->em485->stop_tx_timer.function = &serial8250_em485_handle_stop_tx;
- p->em485->start_tx_timer.function = &serial8250_em485_handle_start_tx;
+ hrtimer_setup(&p->em485->stop_tx_timer, &serial8250_em485_handle_stop_tx, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL);
+ hrtimer_setup(&p->em485->start_tx_timer, &serial8250_em485_handle_start_tx, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL);
p->em485->port = p;
p->em485->active_timer = NULL;
p->em485->tx_stopped = true;
- p->rs485_stop_tx(p);
+deassert_rts:
+ if (p->em485->tx_stopped)
+ p->rs485_stop_tx(p, true);
return 0;
}
@@ -660,49 +598,35 @@ void serial8250_em485_destroy(struct uart_8250_port *p)
}
EXPORT_SYMBOL_GPL(serial8250_em485_destroy);
+struct serial_rs485 serial8250_em485_supported = {
+ .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND |
+ SER_RS485_TERMINATE_BUS | SER_RS485_RX_DURING_TX,
+ .delay_rts_before_send = 1,
+ .delay_rts_after_send = 1,
+};
+EXPORT_SYMBOL_GPL(serial8250_em485_supported);
+
/**
* serial8250_em485_config() - generic ->rs485_config() callback
* @port: uart port
+ * @termios: termios structure
* @rs485: rs485 settings
*
* Generic callback usable by 8250 uart drivers to activate rs485 settings
* if the uart is incapable of driving RTS as a Transmit Enable signal in
* hardware, relying on software emulation instead.
*/
-int serial8250_em485_config(struct uart_port *port, struct serial_rs485 *rs485)
+int serial8250_em485_config(struct uart_port *port, struct ktermios *termios,
+ struct serial_rs485 *rs485)
{
struct uart_8250_port *up = up_to_u8250p(port);
- /* pick sane settings if the user hasn't */
- if (!!(rs485->flags & SER_RS485_RTS_ON_SEND) ==
- !!(rs485->flags & SER_RS485_RTS_AFTER_SEND)) {
- rs485->flags |= SER_RS485_RTS_ON_SEND;
- rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;
- }
-
- /* clamp the delays to [0, 100ms] */
- rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
- rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U);
-
- memset(rs485->padding, 0, sizeof(rs485->padding));
- port->rs485 = *rs485;
-
- gpiod_set_value(port->rs485_term_gpio,
- rs485->flags & SER_RS485_TERMINATE_BUS);
-
/*
* Both serial8250_em485_init() and serial8250_em485_destroy()
* are idempotent.
*/
- if (rs485->flags & SER_RS485_ENABLED) {
- int ret = serial8250_em485_init(up);
-
- if (ret) {
- rs485->flags &= ~SER_RS485_ENABLED;
- port->rs485.flags &= ~SER_RS485_ENABLED;
- }
- return ret;
- }
+ if (rs485->flags & SER_RS485_ENABLED)
+ return serial8250_em485_init(up);
serial8250_em485_destroy(up);
return 0;
@@ -714,7 +638,7 @@ EXPORT_SYMBOL_GPL(serial8250_em485_config);
* once and disable_runtime_pm_tx() will still disable RPM because the fifo is
* empty and the HW can idle again.
*/
-void serial8250_rpm_get_tx(struct uart_8250_port *p)
+static void serial8250_rpm_get_tx(struct uart_8250_port *p)
{
unsigned char rpm_active;
@@ -726,9 +650,8 @@ void serial8250_rpm_get_tx(struct uart_8250_port *p)
return;
pm_runtime_get_sync(p->port.dev);
}
-EXPORT_SYMBOL_GPL(serial8250_rpm_get_tx);
-void serial8250_rpm_put_tx(struct uart_8250_port *p)
+static void serial8250_rpm_put_tx(struct uart_8250_port *p)
{
unsigned char rpm_active;
@@ -741,7 +664,6 @@ void serial8250_rpm_put_tx(struct uart_8250_port *p)
pm_runtime_mark_last_busy(p->port.dev);
pm_runtime_put_autosuspend(p->port.dev);
}
-EXPORT_SYMBOL_GPL(serial8250_rpm_put_tx);
/*
* IER sleep support. UARTs which have EFRs need the "extended
@@ -752,95 +674,45 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
{
unsigned char lcr = 0, efr = 0;
- serial8250_rpm_get(p);
+ guard(serial8250_rpm)(p);
- if (p->capabilities & UART_CAP_SLEEP) {
- if (p->capabilities & UART_CAP_EFR) {
- lcr = serial_in(p, UART_LCR);
- efr = serial_in(p, UART_EFR);
- serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
- serial_out(p, UART_EFR, UART_EFR_ECB);
- serial_out(p, UART_LCR, 0);
- }
- serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
- if (p->capabilities & UART_CAP_EFR) {
- serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
- serial_out(p, UART_EFR, efr);
- serial_out(p, UART_LCR, lcr);
- }
- }
-
- serial8250_rpm_put(p);
-}
-
-#ifdef CONFIG_SERIAL_8250_RSA
-/*
- * Attempts to turn on the RSA FIFO. Returns zero on failure.
- * We set the port uart clock rate if we succeed.
- */
-static int __enable_rsa(struct uart_8250_port *up)
-{
- unsigned char mode;
- int result;
+ if (!(p->capabilities & UART_CAP_SLEEP))
+ return;
- mode = serial_in(up, UART_RSA_MSR);
- result = mode & UART_RSA_MSR_FIFO;
+ /* Synchronize UART_IER access against the console. */
+ guard(uart_port_lock_irq)(&p->port);
- if (!result) {
- serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
- mode = serial_in(up, UART_RSA_MSR);
- result = mode & UART_RSA_MSR_FIFO;
+ if (p->capabilities & UART_CAP_EFR) {
+ lcr = serial_in(p, UART_LCR);
+ efr = serial_in(p, UART_EFR);
+ serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(p, UART_EFR, UART_EFR_ECB);
+ serial_out(p, UART_LCR, 0);
+ }
+ serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+ if (p->capabilities & UART_CAP_EFR) {
+ serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(p, UART_EFR, efr);
+ serial_out(p, UART_LCR, lcr);
}
-
- if (result)
- up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
-
- return result;
}
-static void enable_rsa(struct uart_8250_port *up)
+/* Clear the interrupt registers. */
+static void serial8250_clear_interrupts(struct uart_port *port)
{
- if (up->port.type == PORT_RSA) {
- if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
- spin_lock_irq(&up->port.lock);
- __enable_rsa(up);
- spin_unlock_irq(&up->port.lock);
- }
- if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
- serial_out(up, UART_RSA_FRR, 0);
- }
+ serial_port_in(port, UART_LSR);
+ serial_port_in(port, UART_RX);
+ serial_port_in(port, UART_IIR);
+ serial_port_in(port, UART_MSR);
}
-/*
- * Attempts to turn off the RSA FIFO. Returns zero on failure.
- * It is unknown why interrupts were disabled in here. However,
- * the caller is expected to preserve this behaviour by grabbing
- * the spinlock before calling this function.
- */
-static void disable_rsa(struct uart_8250_port *up)
+static void serial8250_clear_IER(struct uart_8250_port *up)
{
- unsigned char mode;
- int result;
-
- if (up->port.type == PORT_RSA &&
- up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
- spin_lock_irq(&up->port.lock);
-
- mode = serial_in(up, UART_RSA_MSR);
- result = !(mode & UART_RSA_MSR_FIFO);
-
- if (!result) {
- serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
- mode = serial_in(up, UART_RSA_MSR);
- result = !(mode & UART_RSA_MSR_FIFO);
- }
-
- if (result)
- up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
- spin_unlock_irq(&up->port.lock);
- }
+ if (up->capabilities & UART_CAP_UUE)
+ serial_out(up, UART_IER, UART_IER_UUE);
+ else
+ serial_out(up, UART_IER, 0);
}
-#endif /* CONFIG_SERIAL_8250_RSA */
/*
* This is a quickie test to see how big the FIFO is.
@@ -849,7 +721,7 @@ static void disable_rsa(struct uart_8250_port *up)
static int size_fifo(struct uart_8250_port *up)
{
unsigned char old_fcr, old_mcr, old_lcr;
- unsigned short old_dl;
+ u32 old_dl;
int count;
old_lcr = serial_in(up, UART_LCR);
@@ -862,7 +734,7 @@ static int size_fifo(struct uart_8250_port *up)
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
old_dl = serial_dl_read(up);
serial_dl_write(up, 0x0001);
- serial_out(up, UART_LCR, 0x03);
+ serial_out(up, UART_LCR, UART_LCR_WLEN8);
for (count = 0; count < 256; count++)
serial_out(up, UART_TX, count);
mdelay(20);/* FIXME - schedule_timeout */
@@ -945,8 +817,6 @@ static void autoconfig_has_efr(struct uart_8250_port *up)
id3 = serial_icr_read(up, UART_ID3);
rev = serial_icr_read(up, UART_REV);
- DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev);
-
if (id1 == 0x16 && id2 == 0xC9 &&
(id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) {
up->port.type = PORT_16C950;
@@ -970,7 +840,6 @@ static void autoconfig_has_efr(struct uart_8250_port *up)
* 0x14 - XR16C854.
*/
id1 = autoconfig_read_divisor_id(up);
- DEBUG_AUTOCONF("850id=%04x ", id1);
id2 = id1 >> 8;
if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) {
@@ -1039,10 +908,14 @@ static void autoconfig_16550a(struct uart_8250_port *up)
unsigned char status1, status2;
unsigned int iersave;
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&up->port.lock);
+
up->port.type = PORT_16550A;
up->capabilities |= UART_CAP_FIFO;
- if (!IS_ENABLED(CONFIG_SERIAL_8250_16550A_VARIANTS))
+ if (!IS_ENABLED(CONFIG_SERIAL_8250_16550A_VARIANTS) &&
+ !(up->port.flags & UPF_FULL_PROBE))
return;
/*
@@ -1053,21 +926,18 @@ static void autoconfig_16550a(struct uart_8250_port *up)
if (serial_in(up, UART_EFR) == 0) {
serial_out(up, UART_EFR, 0xA8);
if (serial_in(up, UART_EFR) != 0) {
- DEBUG_AUTOCONF("EFRv1 ");
up->port.type = PORT_16650;
up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
} else {
serial_out(up, UART_LCR, 0);
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR7_64BYTE);
- status1 = serial_in(up, UART_IIR) >> 5;
+ status1 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;
serial_out(up, UART_FCR, 0);
serial_out(up, UART_LCR, 0);
- if (status1 == 7)
+ if (status1 == UART_IIR_FIFO_ENABLED_16750)
up->port.type = PORT_16550A_FSL64;
- else
- DEBUG_AUTOCONF("Motorola 8xxx DUART ");
}
serial_out(up, UART_EFR, 0);
return;
@@ -1079,7 +949,6 @@ static void autoconfig_16550a(struct uart_8250_port *up)
*/
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
- DEBUG_AUTOCONF("EFRv2 ");
autoconfig_has_efr(up);
return;
}
@@ -1132,17 +1001,18 @@ static void autoconfig_16550a(struct uart_8250_port *up)
*/
serial_out(up, UART_LCR, 0);
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
- status1 = serial_in(up, UART_IIR) >> 5;
+ status1 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
- status2 = serial_in(up, UART_IIR) >> 5;
+ status2 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
- serial_out(up, UART_LCR, 0);
- DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);
+ serial_out(up, UART_LCR, 0);
- if (status1 == 6 && status2 == 7) {
+ if (status1 == UART_IIR_FIFO_ENABLED_16550A &&
+ status2 == UART_IIR_FIFO_ENABLED_16750) {
up->port.type = PORT_16750;
up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;
return;
@@ -1154,7 +1024,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
* internal UARTs.
* We're going to explicitly set the UUE bit to 0 before
* trying to write and read a 1 just to make sure it's not
- * already a 1 and maybe locked there before we even start start.
+ * already a 1 and maybe locked there before we even start.
*/
iersave = serial_in(up, UART_IER);
serial_out(up, UART_IER, iersave & ~UART_IER_UUE);
@@ -1169,17 +1039,10 @@ static void autoconfig_16550a(struct uart_8250_port *up)
* It's an Xscale.
* We'll leave the UART_IER_UUE bit set to 1 (enabled).
*/
- DEBUG_AUTOCONF("Xscale ");
up->port.type = PORT_XSCALE;
up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE;
return;
}
- } else {
- /*
- * If we got here we couldn't force the IER_UUE bit to 0.
- * Log it and continue.
- */
- DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 ");
}
serial_out(up, UART_IER, iersave);
@@ -1211,14 +1074,13 @@ static void autoconfig(struct uart_8250_port *up)
if (!port->iobase && !port->mapbase && !port->membase)
return;
- DEBUG_AUTOCONF("%s: autoconf (0x%04lx, 0x%p): ",
- port->name, port->iobase, port->membase);
-
/*
* We really do need global IRQs disabled here - we're going to
* be frobbing the chips IRQ enable register to see if it exists.
+ *
+ * Synchronize UART_IER access against the console.
*/
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
up->capabilities = 0;
up->bugs = 0;
@@ -1239,28 +1101,26 @@ static void autoconfig(struct uart_8250_port *up)
*/
scratch = serial_in(up, UART_IER);
serial_out(up, UART_IER, 0);
-#ifdef __i386__
+#if defined(__i386__) && defined(CONFIG_HAS_IOPORT)
outb(0xff, 0x080);
#endif
/*
* Mask out IER[7:4] bits for test as some UARTs (e.g. TL
* 16C754B) allow only to modify them if an EFR bit is set.
*/
- scratch2 = serial_in(up, UART_IER) & 0x0f;
- serial_out(up, UART_IER, 0x0F);
-#ifdef __i386__
+ scratch2 = serial_in(up, UART_IER) & UART_IER_ALL_INTR;
+ serial_out(up, UART_IER, UART_IER_ALL_INTR);
+#if defined(__i386__) && defined(CONFIG_HAS_IOPORT)
outb(0, 0x080);
#endif
- scratch3 = serial_in(up, UART_IER) & 0x0f;
+ scratch3 = serial_in(up, UART_IER) & UART_IER_ALL_INTR;
serial_out(up, UART_IER, scratch);
- if (scratch2 != 0 || scratch3 != 0x0F) {
+ if (scratch2 != 0 || scratch3 != UART_IER_ALL_INTR) {
/*
* We failed; there's nothing here
*/
- spin_unlock_irqrestore(&port->lock, flags);
- DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
- scratch2, scratch3);
- goto out;
+ uart_port_unlock_irqrestore(port, flags);
+ return;
}
}
@@ -1277,14 +1137,12 @@ static void autoconfig(struct uart_8250_port *up)
* that conflicts with COM 1-4 --- we hope!
*/
if (!(port->flags & UPF_SKIP_TEST)) {
- serial8250_out_MCR(up, UART_MCR_LOOP | 0x0A);
- status1 = serial_in(up, UART_MSR) & 0xF0;
+ serial8250_out_MCR(up, UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_RTS);
+ status1 = serial_in(up, UART_MSR) & UART_MSR_STATUS_BITS;
serial8250_out_MCR(up, save_mcr);
- if (status1 != 0x90) {
- spin_unlock_irqrestore(&port->lock, flags);
- DEBUG_AUTOCONF("LOOP test failed (%02x) ",
- status1);
- goto out;
+ if (status1 != (UART_MSR_DCD | UART_MSR_CTS)) {
+ uart_port_unlock_irqrestore(port, flags);
+ return;
}
}
@@ -1303,32 +1161,22 @@ static void autoconfig(struct uart_8250_port *up)
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
- /* Assign this as it is to truncate any bits above 7. */
- scratch = serial_in(up, UART_IIR);
-
- switch (scratch >> 6) {
- case 0:
+ switch (serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED) {
+ case UART_IIR_FIFO_ENABLED_8250:
autoconfig_8250(up);
break;
- case 1:
- port->type = PORT_UNKNOWN;
- break;
- case 2:
+ case UART_IIR_FIFO_ENABLED_16550:
port->type = PORT_16550;
break;
- case 3:
+ case UART_IIR_FIFO_ENABLED_16550A:
autoconfig_16550a(up);
break;
+ default:
+ port->type = PORT_UNKNOWN;
+ break;
}
-#ifdef CONFIG_SERIAL_8250_RSA
- /*
- * Only probe for RSA ports if we got the region.
- */
- if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA &&
- __enable_rsa(up))
- port->type = PORT_RSA;
-#endif
+ rsa_autoconfig(up);
serial_out(up, UART_LCR, save_lcr);
@@ -1337,26 +1185,18 @@ static void autoconfig(struct uart_8250_port *up)
up->capabilities = uart_config[port->type].flags;
up->tx_loadsz = uart_config[port->type].tx_loadsz;
- if (port->type == PORT_UNKNOWN)
- goto out_unlock;
-
- /*
- * Reset the UART.
- */
-#ifdef CONFIG_SERIAL_8250_RSA
- if (port->type == PORT_RSA)
- serial_out(up, UART_RSA_FRR, 0);
-#endif
- serial8250_out_MCR(up, save_mcr);
- serial8250_clear_fifos(up);
- serial_in(up, UART_RX);
- if (up->capabilities & UART_CAP_UUE)
- serial_out(up, UART_IER, UART_IER_UUE);
- else
- serial_out(up, UART_IER, 0);
+ if (port->type != PORT_UNKNOWN) {
+ /*
+ * Reset the UART.
+ */
+ rsa_reset(up);
+ serial8250_out_MCR(up, save_mcr);
+ serial8250_clear_fifos(up);
+ serial_in(up, UART_RX);
+ serial8250_clear_IER(up);
+ }
-out_unlock:
- spin_unlock_irqrestore(&port->lock, flags);
+ uart_port_unlock_irqrestore(port, flags);
/*
* Check if the device is a Fintek F81216A
@@ -1368,9 +1208,6 @@ out_unlock:
dev_warn(port->dev, "detected caps %08x should be %08x\n",
old_capabilities, up->capabilities);
}
-out:
- DEBUG_AUTOCONF("iir=%d ", scratch);
- DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name);
}
static void autoconfig_irq(struct uart_8250_port *up)
@@ -1389,13 +1226,12 @@ static void autoconfig_irq(struct uart_8250_port *up)
inb_p(ICP);
}
- if (uart_console(port))
- console_lock();
-
/* forget possible initially masked and pending IRQ */
probe_irq_off(probe_irq_on());
save_mcr = serial8250_in_MCR(up);
- save_ier = serial_in(up, UART_IER);
+ /* Synchronize UART_IER access against the console. */
+ scoped_guard(uart_port_lock_irq, port)
+ save_ier = serial_in(up, UART_IER);
serial8250_out_MCR(up, UART_MCR_OUT1 | UART_MCR_OUT2);
irqs = probe_irq_on();
@@ -1407,24 +1243,22 @@ static void autoconfig_irq(struct uart_8250_port *up)
serial8250_out_MCR(up,
UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
}
- serial_out(up, UART_IER, 0x0f); /* enable all intrs */
- serial_in(up, UART_LSR);
- serial_in(up, UART_RX);
- serial_in(up, UART_IIR);
- serial_in(up, UART_MSR);
+ /* Synchronize UART_IER access against the console. */
+ scoped_guard(uart_port_lock_irq, port)
+ serial_out(up, UART_IER, UART_IER_ALL_INTR);
+ serial8250_clear_interrupts(port);
serial_out(up, UART_TX, 0xFF);
udelay(20);
irq = probe_irq_off(irqs);
serial8250_out_MCR(up, save_mcr);
- serial_out(up, UART_IER, save_ier);
+ /* Synchronize UART_IER access against the console. */
+ scoped_guard(uart_port_lock_irq, port)
+ serial_out(up, UART_IER, save_ier);
if (port->flags & UPF_FOURPORT)
outb_p(save_ICP, ICP);
- if (uart_console(port))
- console_unlock();
-
port->irq = (irq > 0) ? irq : 0;
}
@@ -1432,25 +1266,29 @@ static void serial8250_stop_rx(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- serial8250_rpm_get(up);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&port->lock);
+
+ guard(serial8250_rpm)(up);
up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
- up->port.read_status_mask &= ~UART_LSR_DR;
serial_port_out(port, UART_IER, up->ier);
-
- serial8250_rpm_put(up);
}
/**
* serial8250_em485_stop_tx() - generic ->rs485_stop_tx() callback
* @p: uart 8250 port
+ * @toggle_ier: true to allow enabling receive interrupts
*
* Generic callback usable by 8250 uart drivers to stop rs485 transmission.
*/
-void serial8250_em485_stop_tx(struct uart_8250_port *p)
+void serial8250_em485_stop_tx(struct uart_8250_port *p, bool toggle_ier)
{
unsigned char mcr = serial8250_in_MCR(p);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&p->port.lock);
+
if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND)
mcr |= UART_MCR_RTS;
else
@@ -1465,8 +1303,10 @@ void serial8250_em485_stop_tx(struct uart_8250_port *p)
if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX)) {
serial8250_clear_and_reinit_fifos(p);
- p->ier |= UART_IER_RLSI | UART_IER_RDI;
- serial_port_out(&p->port, UART_IER, p->ier);
+ if (toggle_ier) {
+ p->ier |= UART_IER_RLSI | UART_IER_RDI;
+ serial_port_out(&p->port, UART_IER, p->ier);
+ }
}
}
EXPORT_SYMBOL_GPL(serial8250_em485_stop_tx);
@@ -1476,17 +1316,15 @@ static enum hrtimer_restart serial8250_em485_handle_stop_tx(struct hrtimer *t)
struct uart_8250_em485 *em485 = container_of(t, struct uart_8250_em485,
stop_tx_timer);
struct uart_8250_port *p = em485->port;
- unsigned long flags;
- serial8250_rpm_get(p);
- spin_lock_irqsave(&p->port.lock, flags);
+ guard(serial8250_rpm)(p);
+ guard(uart_port_lock_irqsave)(&p->port);
+
if (em485->active_timer == &em485->stop_tx_timer) {
- p->rs485_stop_tx(p);
+ p->rs485_stop_tx(p, true);
em485->active_timer = NULL;
em485->tx_stopped = true;
}
- spin_unlock_irqrestore(&p->port.lock, flags);
- serial8250_rpm_put(p);
return HRTIMER_NORESTART;
}
@@ -1496,56 +1334,72 @@ static void start_hrtimer_ms(struct hrtimer *hrt, unsigned long msec)
hrtimer_start(hrt, ms_to_ktime(msec), HRTIMER_MODE_REL);
}
-static void __stop_tx_rs485(struct uart_8250_port *p)
+static void __stop_tx_rs485(struct uart_8250_port *p, u64 stop_delay)
{
struct uart_8250_em485 *em485 = p->em485;
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&p->port.lock);
+
+ stop_delay += (u64)p->port.rs485.delay_rts_after_send * NSEC_PER_MSEC;
+
/*
* rs485_stop_tx() is going to set RTS according to config
* AND flush RX FIFO if required.
*/
- if (p->port.rs485.delay_rts_after_send > 0) {
+ if (stop_delay > 0) {
em485->active_timer = &em485->stop_tx_timer;
- start_hrtimer_ms(&em485->stop_tx_timer,
- p->port.rs485.delay_rts_after_send);
+ hrtimer_start(&em485->stop_tx_timer, ns_to_ktime(stop_delay), HRTIMER_MODE_REL);
} else {
- p->rs485_stop_tx(p);
+ p->rs485_stop_tx(p, true);
em485->active_timer = NULL;
em485->tx_stopped = true;
}
}
-static inline void __do_stop_tx(struct uart_8250_port *p)
-{
- if (serial8250_clear_THRI(p))
- serial8250_rpm_put_tx(p);
-}
-
static inline void __stop_tx(struct uart_8250_port *p)
{
struct uart_8250_em485 *em485 = p->em485;
if (em485) {
- unsigned char lsr = serial_in(p, UART_LSR);
+ u16 lsr = serial_lsr_in(p);
+ u64 stop_delay = 0;
+
+ if (!(lsr & UART_LSR_THRE))
+ return;
/*
- * To provide required timeing and allow FIFO transfer,
+ * To provide required timing and allow FIFO transfer,
* __stop_tx_rs485() must be called only when both FIFO and
- * shift register are empty. It is for device driver to enable
- * interrupt on TEMT.
+ * shift register are empty. The device driver should either
+ * enable interrupt on TEMT or set UART_CAP_NOTEMT that will
+ * enlarge stop_tx_timer by the tx time of one frame to cover
+ * for emptying of the shift register.
*/
- if ((lsr & BOTH_EMPTY) != BOTH_EMPTY)
- return;
+ if (!(lsr & UART_LSR_TEMT)) {
+ if (!(p->capabilities & UART_CAP_NOTEMT))
+ return;
+ /*
+ * RTS might get deasserted too early with the normal
+ * frame timing formula. It seems to suggest THRE might
+ * get asserted already during tx of the stop bit
+ * rather than after it is fully sent.
+ * Roughly estimate 1 extra bit here with / 7.
+ */
+ stop_delay = p->port.frame_time + DIV_ROUND_UP(p->port.frame_time, 7);
+ }
- __stop_tx_rs485(p);
+ __stop_tx_rs485(p, stop_delay);
}
- __do_stop_tx(p);
+
+ if (serial8250_clear_THRI(p))
+ serial8250_rpm_put_tx(p);
}
static void serial8250_stop_tx(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
__stop_tx(up);
/*
@@ -1555,7 +1409,6 @@ static void serial8250_stop_tx(struct uart_port *port)
up->acr |= UART_ACR_TXDIS;
serial_icr_write(up, UART_ACR, up->acr);
}
- serial8250_rpm_put(up);
}
static inline void __start_tx(struct uart_port *port)
@@ -1567,10 +1420,8 @@ static inline void __start_tx(struct uart_port *port)
if (serial8250_set_THRI(up)) {
if (up->bugs & UART_BUG_TXEN) {
- unsigned char lsr;
+ u16 lsr = serial_lsr_in(up);
- lsr = serial_in(up, UART_LSR);
- up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
if (lsr & UART_LSR_THRE)
serial8250_tx_chars(up);
}
@@ -1588,6 +1439,7 @@ static inline void __start_tx(struct uart_port *port)
/**
* serial8250_em485_start_tx() - generic ->rs485_start_tx() callback
* @up: uart 8250 port
+ * @toggle_ier: true to allow disabling receive interrupts
*
* Generic callback usable by 8250 uart drivers to start rs485 transmission.
* Assumes that setting the RTS bit in the MCR register means RTS is high.
@@ -1595,11 +1447,11 @@ static inline void __start_tx(struct uart_port *port)
* stoppable by disabling the UART_IER_RDI interrupt. (Some chips set the
* UART_LSR_DR bit even when UART_IER_RDI is disabled, foiling this approach.)
*/
-void serial8250_em485_start_tx(struct uart_8250_port *up)
+void serial8250_em485_start_tx(struct uart_8250_port *up, bool toggle_ier)
{
unsigned char mcr = serial8250_in_MCR(up);
- if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX))
+ if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX) && toggle_ier)
serial8250_stop_rx(&up->port);
if (up->port.rs485.flags & SER_RS485_RTS_ON_SEND)
@@ -1610,27 +1462,40 @@ void serial8250_em485_start_tx(struct uart_8250_port *up)
}
EXPORT_SYMBOL_GPL(serial8250_em485_start_tx);
-static inline void start_tx_rs485(struct uart_port *port)
+/* Returns false, if start_tx_timer was setup to defer TX start */
+static bool start_tx_rs485(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
struct uart_8250_em485 *em485 = up->em485;
+ /*
+ * While serial8250_em485_handle_stop_tx() is a noop if
+ * em485->active_timer != &em485->stop_tx_timer, it might happen that
+ * the timer is still armed and triggers only after the current bunch of
+ * chars is send and em485->active_timer == &em485->stop_tx_timer again.
+ * So cancel the timer. There is still a theoretical race condition if
+ * the timer is already running and only comes around to check for
+ * em485->active_timer when &em485->stop_tx_timer is armed again.
+ */
+ if (em485->active_timer == &em485->stop_tx_timer)
+ hrtimer_try_to_cancel(&em485->stop_tx_timer);
+
em485->active_timer = NULL;
if (em485->tx_stopped) {
em485->tx_stopped = false;
- up->rs485_start_tx(up);
+ up->rs485_start_tx(up, true);
if (up->port.rs485.delay_rts_before_send > 0) {
em485->active_timer = &em485->start_tx_timer;
start_hrtimer_ms(&em485->start_tx_timer,
up->port.rs485.delay_rts_before_send);
- return;
+ return false;
}
}
- __start_tx(port);
+ return true;
}
static enum hrtimer_restart serial8250_em485_handle_start_tx(struct hrtimer *t)
@@ -1638,14 +1503,13 @@ static enum hrtimer_restart serial8250_em485_handle_start_tx(struct hrtimer *t)
struct uart_8250_em485 *em485 = container_of(t, struct uart_8250_em485,
start_tx_timer);
struct uart_8250_port *p = em485->port;
- unsigned long flags;
- spin_lock_irqsave(&p->port.lock, flags);
+ guard(uart_port_lock_irqsave)(&p->port);
+
if (em485->active_timer == &em485->start_tx_timer) {
__start_tx(&p->port);
em485->active_timer = NULL;
}
- spin_unlock_irqrestore(&p->port.lock, flags);
return HRTIMER_NORESTART;
}
@@ -1655,16 +1519,20 @@ static void serial8250_start_tx(struct uart_port *port)
struct uart_8250_port *up = up_to_u8250p(port);
struct uart_8250_em485 *em485 = up->em485;
- serial8250_rpm_get_tx(up);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&port->lock);
- if (em485 &&
- em485->active_timer == &em485->start_tx_timer)
+ if (!port->x_char && kfifo_is_empty(&port->state->port.xmit_fifo))
return;
- if (em485)
- start_tx_rs485(port);
- else
- __start_tx(port);
+ serial8250_rpm_get_tx(up);
+
+ if (em485) {
+ if ((em485->active_timer == &em485->start_tx_timer) ||
+ !start_tx_rs485(port))
+ return;
+ }
+ __start_tx(port);
}
static void serial8250_throttle(struct uart_port *port)
@@ -1681,11 +1549,14 @@ static void serial8250_disable_ms(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&port->lock);
+
/* no MSR capabilities */
if (up->bugs & UART_BUG_NOMSR)
return;
- mctrl_gpio_disable_ms(up->gpios);
+ mctrl_gpio_disable_ms_no_sync(up->gpios);
up->ier &= ~UART_IER_MSI;
serial_port_out(port, UART_IER, up->ier);
@@ -1695,6 +1566,9 @@ static void serial8250_enable_ms(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&port->lock);
+
/* no MSR capabilities */
if (up->bugs & UART_BUG_NOMSR)
return;
@@ -1703,16 +1577,14 @@ static void serial8250_enable_ms(struct uart_port *port)
up->ier |= UART_IER_MSI;
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
serial_port_out(port, UART_IER, up->ier);
- serial8250_rpm_put(up);
}
-void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr)
+void serial8250_read_char(struct uart_8250_port *up, u16 lsr)
{
struct uart_port *port = &up->port;
- unsigned char ch;
- char flag = TTY_NORMAL;
+ u8 ch, flag = TTY_NORMAL;
if (likely(lsr & UART_LSR_DR))
ch = serial_in(up, UART_RX);
@@ -1771,11 +1643,13 @@ void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr)
EXPORT_SYMBOL_GPL(serial8250_read_char);
/*
- * serial8250_rx_chars: processes according to the passed in LSR
- * value, and returns the remaining LSR bits not handled
- * by this Rx routine.
+ * serial8250_rx_chars - Read characters. The first LSR value must be passed in.
+ *
+ * Returns LSR bits. The caller should rely only on non-Rx related LSR bits
+ * (such as THRE) because the LSR value might come from an already consumed
+ * character.
*/
-unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
+u16 serial8250_rx_chars(struct uart_8250_port *up, u16 lsr)
{
struct uart_port *port = &up->port;
int max_count = 256;
@@ -1795,27 +1669,30 @@ EXPORT_SYMBOL_GPL(serial8250_rx_chars);
void serial8250_tx_chars(struct uart_8250_port *up)
{
struct uart_port *port = &up->port;
- struct circ_buf *xmit = &port->state->xmit;
+ struct tty_port *tport = &port->state->port;
int count;
if (port->x_char) {
- serial_out(up, UART_TX, port->x_char);
- port->icount.tx++;
- port->x_char = 0;
+ uart_xchar_out(port, UART_TX);
return;
}
if (uart_tx_stopped(port)) {
serial8250_stop_tx(port);
return;
}
- if (uart_circ_empty(xmit)) {
+ if (kfifo_is_empty(&tport->xmit_fifo)) {
__stop_tx(up);
return;
}
count = up->tx_loadsz;
do {
- serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+ unsigned char c;
+
+ if (!uart_fifo_get(port, &c))
+ break;
+
+ serial_out(up, UART_TX, c);
if (up->bugs & UART_BUG_TXRACE) {
/*
* The Aspeed BMC virtual UARTs have a bug where data
@@ -1828,12 +1705,9 @@ void serial8250_tx_chars(struct uart_8250_port *up)
*/
serial_in(up, UART_SCR);
}
- xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
- port->icount.tx++;
- if (uart_circ_empty(xmit))
- break;
+
if ((up->capabilities & UART_CAP_HFIFO) &&
- (serial_in(up, UART_LSR) & BOTH_EMPTY) != BOTH_EMPTY)
+ !uart_lsr_tx_empty(serial_in(up, UART_LSR)))
break;
/* The BCM2835 MINI UART THRE bit is really a not-full bit. */
if ((up->capabilities & UART_CAP_MINI) &&
@@ -1841,7 +1715,7 @@ void serial8250_tx_chars(struct uart_8250_port *up)
break;
} while (--count > 0);
- if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
uart_write_wakeup(port);
/*
@@ -1849,7 +1723,8 @@ void serial8250_tx_chars(struct uart_8250_port *up)
* HW can go idle. So we get here once again with empty FIFO and disable
* the interrupt and RPM in __stop_tx()
*/
- if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM))
+ if (kfifo_is_empty(&tport->xmit_fifo) &&
+ !(up->capabilities & UART_CAP_RPM))
__stop_tx(up);
}
EXPORT_SYMBOL_GPL(serial8250_tx_chars);
@@ -1883,10 +1758,24 @@ EXPORT_SYMBOL_GPL(serial8250_modem_status);
static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
{
switch (iir & 0x3f) {
- case UART_IIR_RX_TIMEOUT:
- serial8250_rx_dma_flush(up);
+ case UART_IIR_THRI:
+ /*
+ * Postpone DMA or not decision to IIR_RDI or IIR_RX_TIMEOUT
+ * because it's impossible to do an informed decision about
+ * that with IIR_THRI.
+ *
+ * This also fixes one known DMA Rx corruption issue where
+ * DR is asserted but DMA Rx only gets a corrupted zero byte
+ * (too early DR?).
+ */
+ return false;
+ case UART_IIR_RDI:
+ if (!up->dma->rx_running)
+ break;
fallthrough;
case UART_IIR_RLSI:
+ case UART_IIR_RX_TIMEOUT:
+ serial8250_rx_dma_flush(up);
return true;
}
return up->dma->rx_dma(up);
@@ -1897,17 +1786,18 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
*/
int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
{
- unsigned char status;
struct uart_8250_port *up = up_to_u8250p(port);
+ struct tty_port *tport = &port->state->port;
bool skip_rx = false;
unsigned long flags;
+ u16 status;
if (iir & UART_IIR_NO_INT)
return 0;
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
- status = serial_port_in(port, UART_LSR);
+ status = serial_lsr_in(up);
/*
* If port is stopped and there are no error conditions in the
@@ -1919,17 +1809,25 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
*/
if (!(status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS)) &&
(port->status & (UPSTAT_AUTOCTS | UPSTAT_AUTORTS)) &&
- !(port->read_status_mask & UART_LSR_DR))
+ !(up->ier & (UART_IER_RLSI | UART_IER_RDI)))
skip_rx = true;
if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) {
+ struct irq_data *d;
+
+ d = irq_get_irq_data(port->irq);
+ if (d && irqd_is_wakeup_set(d))
+ pm_wakeup_event(tport->tty->dev, 0);
if (!up->dma || handle_rx_dma(up, iir))
status = serial8250_rx_chars(up, status);
}
serial8250_modem_status(up);
- if ((!up->dma || up->dma->tx_err) && (status & UART_LSR_THRE) &&
- (up->ier & UART_IER_THRI))
- serial8250_tx_chars(up);
+ if ((status & UART_LSR_THRE) && (up->ier & UART_IER_THRI)) {
+ if (!up->dma || up->dma->tx_err)
+ serial8250_tx_chars(up);
+ else if (!up->dma->tx_running)
+ __stop_tx(up);
+ }
uart_unlock_and_check_sysrq_irqrestore(port, flags);
@@ -1941,15 +1839,11 @@ static int serial8250_default_handle_irq(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
unsigned int iir;
- int ret;
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
iir = serial_port_in(port, UART_IIR);
- ret = serial8250_handle_irq(port, iir);
-
- serial8250_rpm_put(up);
- return ret;
+ return serial8250_handle_irq(port, iir);
}
/*
@@ -1960,16 +1854,14 @@ static int serial8250_default_handle_irq(struct uart_port *port)
*/
static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
{
- unsigned long flags;
unsigned int iir = serial_port_in(port, UART_IIR);
/* TX Threshold IRQ triggered so load up FIFO */
if ((iir & UART_IIR_ID) == UART_IIR_THRI) {
struct uart_8250_port *up = up_to_u8250p(port);
- spin_lock_irqsave(&port->lock, flags);
+ guard(uart_port_lock_irqsave)(port);
serial8250_tx_chars(up);
- spin_unlock_irqrestore(&port->lock, flags);
}
iir = serial_port_in(port, UART_IIR);
@@ -1979,19 +1871,14 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
static unsigned int serial8250_tx_empty(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned long flags;
- unsigned int lsr;
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
+ guard(uart_port_lock_irqsave)(port);
- spin_lock_irqsave(&port->lock, flags);
- lsr = serial_port_in(port, UART_LSR);
- up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
- spin_unlock_irqrestore(&port->lock, flags);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ return TIOCSER_TEMT;
- serial8250_rpm_put(up);
-
- return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0;
+ return 0;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
@@ -2000,9 +1887,8 @@ unsigned int serial8250_do_get_mctrl(struct uart_port *port)
unsigned int status;
unsigned int val;
- serial8250_rpm_get(up);
- status = serial8250_modem_status(up);
- serial8250_rpm_put(up);
+ scoped_guard(serial8250_rpm, up)
+ status = serial8250_modem_status(up);
val = serial8250_MSR_to_TIOCM(status);
if (up->gpios)
@@ -2034,6 +1920,9 @@ EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl);
static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
+ if (port->rs485.flags & SER_RS485_ENABLED)
+ return;
+
if (port->set_mctrl)
port->set_mctrl(port, mctrl);
else
@@ -2043,28 +1932,33 @@ static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
static void serial8250_break_ctl(struct uart_port *port, int break_state)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned long flags;
- serial8250_rpm_get(up);
- spin_lock_irqsave(&port->lock, flags);
+ guard(serial8250_rpm)(up);
+ guard(uart_port_lock_irqsave)(port);
+
if (break_state == -1)
up->lcr |= UART_LCR_SBC;
else
up->lcr &= ~UART_LCR_SBC;
serial_port_out(port, UART_LCR, up->lcr);
- spin_unlock_irqrestore(&port->lock, flags);
- serial8250_rpm_put(up);
}
-static void wait_for_lsr(struct uart_8250_port *up, int bits)
+/* Returns true if @bits were set, false on timeout */
+static bool wait_for_lsr(struct uart_8250_port *up, int bits)
{
- unsigned int status, tmout = 10000;
+ unsigned int status, tmout;
- /* Wait up to 10ms for the character(s) to be sent. */
- for (;;) {
- status = serial_in(up, UART_LSR);
+ /*
+ * Wait for a character to be sent. Fallback to a safe default
+ * timeout value if @frame_time is not available.
+ */
+ if (up->port.frame_time)
+ tmout = up->port.frame_time * 2 / NSEC_PER_USEC;
+ else
+ tmout = 10000;
- up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
+ for (;;) {
+ status = serial_lsr_in(up);
if ((status & bits) == bits)
break;
@@ -2073,11 +1967,11 @@ static void wait_for_lsr(struct uart_8250_port *up, int bits)
udelay(1);
touch_nmi_watchdog();
}
+
+ return (tmout != 0);
}
-/*
- * Wait for transmitter & holding register to empty
- */
+/* Wait for transmitter and holding register to empty with timeout */
static void wait_for_xmitr(struct uart_8250_port *up, int bits)
{
unsigned int tmout;
@@ -2106,22 +2000,15 @@ static void wait_for_xmitr(struct uart_8250_port *up, int bits)
static int serial8250_get_poll_char(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned char lsr;
- int status;
+ u16 lsr;
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
lsr = serial_port_in(port, UART_LSR);
+ if (!(lsr & UART_LSR_DR))
+ return NO_POLL_CHAR;
- if (!(lsr & UART_LSR_DR)) {
- status = NO_POLL_CHAR;
- goto out;
- }
-
- status = serial_port_in(port, UART_RX);
-out:
- serial8250_rpm_put(up);
- return status;
+ return serial_port_in(port, UART_RX);
}
@@ -2131,17 +2018,22 @@ static void serial8250_put_poll_char(struct uart_port *port,
unsigned int ier;
struct uart_8250_port *up = up_to_u8250p(port);
- serial8250_rpm_get(up);
+ /*
+ * Normally the port is locked to synchronize UART_IER access
+ * against the console. However, this function is only used by
+ * KDB/KGDB, where it may not be possible to acquire the port
+ * lock because all other CPUs are quiesced. The quiescence
+ * should allow safe lockless usage here.
+ */
+
+ guard(serial8250_rpm)(up);
/*
* First save the IER then disable the interrupts
*/
ier = serial_port_in(port, UART_IER);
- if (up->capabilities & UART_CAP_UUE)
- serial_port_out(port, UART_IER, UART_IER_UUE);
- else
- serial_port_out(port, UART_IER, 0);
+ serial8250_clear_IER(up);
- wait_for_xmitr(up, BOTH_EMPTY);
+ wait_for_xmitr(up, UART_LSR_BOTH_EMPTY);
/*
* Send the character out.
*/
@@ -2151,34 +2043,24 @@ static void serial8250_put_poll_char(struct uart_port *port,
* Finally, wait for transmitter to become empty
* and restore the IER
*/
- wait_for_xmitr(up, BOTH_EMPTY);
+ wait_for_xmitr(up, UART_LSR_BOTH_EMPTY);
serial_port_out(port, UART_IER, ier);
- serial8250_rpm_put(up);
}
#endif /* CONFIG_CONSOLE_POLL */
-int serial8250_do_startup(struct uart_port *port)
+static void serial8250_startup_special(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned long flags;
- unsigned char lsr, iir;
- int retval;
-
- if (!port->fifosize)
- port->fifosize = uart_config[port->type].fifo_size;
- if (!up->tx_loadsz)
- up->tx_loadsz = uart_config[port->type].tx_loadsz;
- if (!up->capabilities)
- up->capabilities = uart_config[port->type].flags;
- up->mcr = 0;
- if (port->iotype != up->cur_iotype)
- set_io_from_upio(port);
-
- serial8250_rpm_get(up);
- if (port->type == PORT_16C950) {
- /* Wake up and initialize UART */
+ switch (port->type) {
+ case PORT_16C950: {
+ /*
+ * Wake up and initialize UART
+ *
+ * Synchronize UART_IER access against the console.
+ */
+ guard(uart_port_lock_irqsave)(port);
up->acr = 0;
serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
serial_port_out(port, UART_EFR, UART_EFR_ECB);
@@ -2188,12 +2070,18 @@ int serial8250_do_startup(struct uart_port *port)
serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
serial_port_out(port, UART_EFR, UART_EFR_ECB);
serial_port_out(port, UART_LCR, 0);
+ break;
}
-
- if (port->type == PORT_DA830) {
- /* Reset the port */
- serial_port_out(port, UART_IER, 0);
- serial_port_out(port, UART_DA830_PWREMU_MGMT, 0);
+ case PORT_DA830:
+ /*
+ * Reset the port
+ *
+ * Synchronize UART_IER access against the console.
+ */
+ scoped_guard(uart_port_lock_irqsave, port) {
+ serial_port_out(port, UART_IER, 0);
+ serial_port_out(port, UART_DA830_PWREMU_MGMT, 0);
+ }
mdelay(10);
/* Enable Tx, Rx and free run mode */
@@ -2201,200 +2089,217 @@ int serial8250_do_startup(struct uart_port *port)
UART_DA830_PWREMU_MGMT_UTRST |
UART_DA830_PWREMU_MGMT_URRST |
UART_DA830_PWREMU_MGMT_FREE);
+ break;
+ case PORT_RSA:
+ rsa_enable(up);
+ break;
}
+}
- if (port->type == PORT_NPCM) {
- /*
- * Nuvoton calls the scratch register 'UART_TOR' (timeout
- * register). Enable it, and set TIOC (timeout interrupt
- * comparator) to be 0x20 for correct operation.
- */
- serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
- }
-
-#ifdef CONFIG_SERIAL_8250_RSA
- /*
- * If this is an RSA port, see if we can kick it up to the
- * higher speed clock.
- */
- enable_rsa(up);
-#endif
-
- /*
- * Clear the FIFO buffers and disable them.
- * (they will be reenabled in set_termios())
- */
- serial8250_clear_fifos(up);
-
- /*
- * Clear the interrupt registers.
- */
- serial_port_in(port, UART_LSR);
- serial_port_in(port, UART_RX);
- serial_port_in(port, UART_IIR);
- serial_port_in(port, UART_MSR);
-
- /*
- * At this point, there's no way the LSR could still be 0xff;
- * if it is, then bail out, because there's likely no UART
- * here.
- */
- if (!(port->flags & UPF_BUGGY_UART) &&
- (serial_port_in(port, UART_LSR) == 0xff)) {
- dev_info_ratelimited(port->dev, "LSR safety check engaged!\n");
- retval = -ENODEV;
- goto out;
- }
+static void serial8250_set_TRG_levels(struct uart_port *port)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
- /*
- * For a XR16C850, we need to set the trigger levels
- */
- if (port->type == PORT_16850) {
- unsigned char fctr;
+ switch (port->type) {
+ /* For a XR16C850, we need to set the trigger levels */
+ case PORT_16850: {
+ u8 fctr;
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
- serial_port_out(port, UART_FCTR,
- fctr | UART_FCTR_TRGD | UART_FCTR_RX);
+ fctr |= UART_FCTR_TRGD;
+ serial_port_out(port, UART_FCTR, fctr | UART_FCTR_RX);
serial_port_out(port, UART_TRG, UART_TRG_96);
- serial_port_out(port, UART_FCTR,
- fctr | UART_FCTR_TRGD | UART_FCTR_TX);
+ serial_port_out(port, UART_FCTR, fctr | UART_FCTR_TX);
serial_port_out(port, UART_TRG, UART_TRG_96);
serial_port_out(port, UART_LCR, 0);
+ break;
}
+ /* For the Altera 16550 variants, set TX threshold trigger level. */
+ case PORT_ALTR_16550_F32:
+ case PORT_ALTR_16550_F64:
+ case PORT_ALTR_16550_F128:
+ if (port->fifosize <= 1)
+ return;
- /*
- * For the Altera 16550 variants, set TX threshold trigger level.
- */
- if (((port->type == PORT_ALTR_16550_F32) ||
- (port->type == PORT_ALTR_16550_F64) ||
- (port->type == PORT_ALTR_16550_F128)) && (port->fifosize > 1)) {
/* Bounds checking of TX threshold (valid 0 to fifosize-2) */
- if ((up->tx_loadsz < 2) || (up->tx_loadsz > port->fifosize)) {
+ if (up->tx_loadsz < 2 || up->tx_loadsz > port->fifosize) {
dev_err(port->dev, "TX FIFO Threshold errors, skipping\n");
- } else {
- serial_port_out(port, UART_ALTR_AFR,
- UART_ALTR_EN_TXFIFO_LW);
- serial_port_out(port, UART_ALTR_TX_LOW,
- port->fifosize - up->tx_loadsz);
- port->handle_irq = serial8250_tx_threshold_handle_irq;
+ return;
}
+ serial_port_out(port, UART_ALTR_AFR, UART_ALTR_EN_TXFIFO_LW);
+ serial_port_out(port, UART_ALTR_TX_LOW, port->fifosize - up->tx_loadsz);
+ port->handle_irq = serial8250_tx_threshold_handle_irq;
+ break;
}
+}
- /* Check if we need to have shared IRQs */
- if (port->irq && (up->port.flags & UPF_SHARE_IRQ))
- up->port.irqflags |= IRQF_SHARED;
+static void serial8250_THRE_test(struct uart_port *port)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ bool iir_noint1, iir_noint2;
- if (port->irq && !(up->port.flags & UPF_NO_THRE_TEST)) {
- unsigned char iir1;
+ if (!port->irq)
+ return;
- if (port->irqflags & IRQF_SHARED)
- disable_irq_nosync(port->irq);
+ if (up->port.flags & UPF_NO_THRE_TEST)
+ return;
- /*
- * Test for UARTs that do not reassert THRE when the
- * transmitter is idle and the interrupt has already
- * been cleared. Real 16550s should always reassert
- * this interrupt whenever the transmitter is idle and
- * the interrupt is enabled. Delays are necessary to
- * allow register changes to become visible.
- */
- spin_lock_irqsave(&port->lock, flags);
+ if (port->irqflags & IRQF_SHARED)
+ disable_irq_nosync(port->irq);
+ /*
+ * Test for UARTs that do not reassert THRE when the transmitter is idle and the interrupt
+ * has already been cleared. Real 16550s should always reassert this interrupt whenever the
+ * transmitter is idle and the interrupt is enabled. Delays are necessary to allow register
+ * changes to become visible.
+ *
+ * Synchronize UART_IER access against the console.
+ */
+ scoped_guard(uart_port_lock_irqsave, port) {
wait_for_xmitr(up, UART_LSR_THRE);
serial_port_out_sync(port, UART_IER, UART_IER_THRI);
udelay(1); /* allow THRE to set */
- iir1 = serial_port_in(port, UART_IIR);
+ iir_noint1 = serial_port_in(port, UART_IIR) & UART_IIR_NO_INT;
serial_port_out(port, UART_IER, 0);
serial_port_out_sync(port, UART_IER, UART_IER_THRI);
udelay(1); /* allow a working UART time to re-assert THRE */
- iir = serial_port_in(port, UART_IIR);
+ iir_noint2 = serial_port_in(port, UART_IIR) & UART_IIR_NO_INT;
serial_port_out(port, UART_IER, 0);
-
- spin_unlock_irqrestore(&port->lock, flags);
-
- if (port->irqflags & IRQF_SHARED)
- enable_irq(port->irq);
-
- /*
- * If the interrupt is not reasserted, or we otherwise
- * don't trust the iir, setup a timer to kick the UART
- * on a regular basis.
- */
- if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) ||
- up->port.flags & UPF_BUG_THRE) {
- up->bugs |= UART_BUG_THRE;
- }
}
- retval = up->ops->setup_irq(up);
- if (retval)
- goto out;
+ if (port->irqflags & IRQF_SHARED)
+ enable_irq(port->irq);
/*
- * Now, initialize the UART
+ * If the interrupt is not reasserted, or we otherwise don't trust the iir, setup a timer to
+ * kick the UART on a regular basis.
*/
- serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+ if ((!iir_noint1 && iir_noint2) || up->port.flags & UPF_BUG_THRE)
+ up->bugs |= UART_BUG_THRE;
+}
- spin_lock_irqsave(&port->lock, flags);
- if (up->port.flags & UPF_FOURPORT) {
- if (!up->port.irq)
- up->port.mctrl |= TIOCM_OUT1;
- } else
- /*
- * Most PC uarts need OUT2 raised to enable interrupts.
- */
+static void serial8250_init_mctrl(struct uart_port *port)
+{
+ if (port->flags & UPF_FOURPORT) {
+ if (!port->irq)
+ port->mctrl |= TIOCM_OUT1;
+ } else {
+ /* Most PC uarts need OUT2 raised to enable interrupts. */
if (port->irq)
- up->port.mctrl |= TIOCM_OUT2;
+ port->mctrl |= TIOCM_OUT2;
+ }
serial8250_set_mctrl(port, port->mctrl);
+}
- /*
- * Serial over Lan (SoL) hack:
- * Intel 8257x Gigabit ethernet chips have a 16550 emulation, to be
- * used for Serial Over Lan. Those chips take a longer time than a
- * normal serial device to signalize that a transmission data was
- * queued. Due to that, the above test generally fails. One solution
- * would be to delay the reading of iir. However, this is not
- * reliable, since the timeout is variable. So, let's just don't
- * test if we receive TX irq. This way, we'll never enable
- * UART_BUG_TXEN.
- */
- if (up->port.quirks & UPQ_NO_TXEN_TEST)
- goto dont_test_tx_en;
+static void serial8250_iir_txen_test(struct uart_port *port)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ bool lsr_temt, iir_noint;
- /*
- * Do a quick test to see if we receive an interrupt when we enable
- * the TX irq.
- */
+ if (port->quirks & UPQ_NO_TXEN_TEST)
+ return;
+
+ /* Do a quick test to see if we receive an interrupt when we enable the TX irq. */
serial_port_out(port, UART_IER, UART_IER_THRI);
- lsr = serial_port_in(port, UART_LSR);
- iir = serial_port_in(port, UART_IIR);
+ lsr_temt = serial_port_in(port, UART_LSR) & UART_LSR_TEMT;
+ iir_noint = serial_port_in(port, UART_IIR) & UART_IIR_NO_INT;
serial_port_out(port, UART_IER, 0);
- if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) {
+ /*
+ * Serial over Lan (SoL) hack:
+ * Intel 8257x Gigabit ethernet chips have a 16550 emulation, to be used for Serial Over
+ * Lan. Those chips take a longer time than a normal serial device to signalize that a
+ * transmission data was queued. Due to that, the above test generally fails. One solution
+ * would be to delay the reading of iir. However, this is not reliable, since the timeout is
+ * variable. So, in case of UPQ_NO_TXEN_TEST, let's just don't test if we receive TX irq.
+ * This way, we'll never enable UART_BUG_TXEN.
+ */
+ if (lsr_temt && iir_noint) {
if (!(up->bugs & UART_BUG_TXEN)) {
up->bugs |= UART_BUG_TXEN;
dev_dbg(port->dev, "enabling bad tx status workarounds\n");
}
- } else {
- up->bugs &= ~UART_BUG_TXEN;
+ return;
}
-dont_test_tx_en:
- spin_unlock_irqrestore(&port->lock, flags);
+ /* FIXME: why is this needed? */
+ up->bugs &= ~UART_BUG_TXEN;
+}
+
+static void serial8250_initialize(struct uart_port *port)
+{
+ guard(uart_port_lock_irqsave)(port);
+ serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+
+ serial8250_init_mctrl(port);
+ serial8250_iir_txen_test(port);
+}
+
+int serial8250_do_startup(struct uart_port *port)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ int retval;
+
+ if (!port->fifosize)
+ port->fifosize = uart_config[port->type].fifo_size;
+ if (!up->tx_loadsz)
+ up->tx_loadsz = uart_config[port->type].tx_loadsz;
+ if (!up->capabilities)
+ up->capabilities = uart_config[port->type].flags;
+ up->mcr = 0;
+
+ if (port->iotype != up->cur_iotype)
+ set_io_from_upio(port);
+
+ guard(serial8250_rpm)(up);
+
+ serial8250_startup_special(port);
+
+ /*
+ * Clear the FIFO buffers and disable them.
+ * (they will be reenabled in set_termios())
+ */
+ serial8250_clear_fifos(up);
+
+ serial8250_clear_interrupts(port);
+
+ /*
+ * At this point, there's no way the LSR could still be 0xff;
+ * if it is, then bail out, because there's likely no UART
+ * here.
+ */
+ if (!(port->flags & UPF_BUGGY_UART) &&
+ (serial_port_in(port, UART_LSR) == 0xff)) {
+ dev_info_ratelimited(port->dev, "LSR safety check engaged!\n");
+ return -ENODEV;
+ }
+
+ serial8250_set_TRG_levels(port);
+
+ /* Check if we need to have shared IRQs */
+ if (port->irq && (up->port.flags & UPF_SHARE_IRQ))
+ up->port.irqflags |= IRQF_SHARED;
+
+ retval = up->ops->setup_irq(up);
+ if (retval)
+ return retval;
+
+ serial8250_THRE_test(port);
+
+ up->ops->setup_timer(up);
+
+ serial8250_initialize(port);
/*
* Clear the interrupt registers again for luck, and clear the
* saved flags to avoid getting false values from polling
* routines or the previous session.
*/
- serial_port_in(port, UART_LSR);
- serial_port_in(port, UART_RX);
- serial_port_in(port, UART_IIR);
- serial_port_in(port, UART_MSR);
+ serial8250_clear_interrupts(port);
up->lsr_saved_flags = 0;
up->msr_saved_flags = 0;
@@ -2430,10 +2335,8 @@ dont_test_tx_en:
outb_p(0x80, icp);
inb_p(icp);
}
- retval = 0;
-out:
- serial8250_rpm_put(up);
- return retval;
+
+ return 0;
}
EXPORT_SYMBOL_GPL(serial8250_do_startup);
@@ -2447,32 +2350,33 @@ static int serial8250_startup(struct uart_port *port)
void serial8250_do_shutdown(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned long flags;
serial8250_rpm_get(up);
/*
* Disable interrupts from this port
+ *
+ * Synchronize UART_IER access against the console.
*/
- spin_lock_irqsave(&port->lock, flags);
- up->ier = 0;
- serial_port_out(port, UART_IER, 0);
- spin_unlock_irqrestore(&port->lock, flags);
+ scoped_guard(uart_port_lock_irqsave, port) {
+ up->ier = 0;
+ serial_port_out(port, UART_IER, 0);
+ }
synchronize_irq(port->irq);
if (up->dma)
serial8250_release_dma(up);
- spin_lock_irqsave(&port->lock, flags);
- if (port->flags & UPF_FOURPORT) {
- /* reset interrupts on the AST Fourport board */
- inb((port->iobase & 0xfe0) | 0x1f);
- port->mctrl |= TIOCM_OUT1;
- } else
- port->mctrl &= ~TIOCM_OUT2;
+ scoped_guard(uart_port_lock_irqsave, port) {
+ if (port->flags & UPF_FOURPORT) {
+ /* reset interrupts on the AST Fourport board */
+ inb((port->iobase & 0xfe0) | 0x1f);
+ port->mctrl |= TIOCM_OUT1;
+ } else
+ port->mctrl &= ~TIOCM_OUT2;
- serial8250_set_mctrl(port, port->mctrl);
- spin_unlock_irqrestore(&port->lock, flags);
+ serial8250_set_mctrl(port, port->mctrl);
+ }
/*
* Disable break condition and FIFOs
@@ -2481,12 +2385,7 @@ void serial8250_do_shutdown(struct uart_port *port)
serial_port_in(port, UART_LCR) & ~UART_LCR_SBC);
serial8250_clear_fifos(up);
-#ifdef CONFIG_SERIAL_8250_RSA
- /*
- * Reset the RSA board back to 115kbps compat mode.
- */
- disable_rsa(up);
-#endif
+ rsa_disable(up);
/*
* Read data port to reset things, and then unlink from
@@ -2507,18 +2406,15 @@ static void serial8250_shutdown(struct uart_port *port)
serial8250_do_shutdown(port);
}
-/* Nuvoton NPCM UARTs have a custom divisor calculation */
-static unsigned int npcm_get_divisor(struct uart_8250_port *up,
- unsigned int baud)
+static void serial8250_flush_buffer(struct uart_port *port)
{
- struct uart_port *port = &up->port;
+ struct uart_8250_port *up = up_to_u8250p(port);
- return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
+ if (up->dma)
+ serial8250_tx_dma_flush(up);
}
-static unsigned int serial8250_do_get_divisor(struct uart_port *port,
- unsigned int baud,
- unsigned int *frac)
+static unsigned int serial8250_do_get_divisor(struct uart_port *port, unsigned int baud)
{
upf_t magic_multiplier = port->flags & UPF_MAGIC_MULTIPLIER;
struct uart_8250_port *up = up_to_u8250p(port);
@@ -2560,8 +2456,6 @@ static unsigned int serial8250_do_get_divisor(struct uart_port *port,
quot = 0x8001;
else if (magic_multiplier && baud >= port->uartclk / 12)
quot = 0x8002;
- else if (up->port.type == PORT_NPCM)
- quot = npcm_get_divisor(up, baud);
else
quot = uart_get_divisor(port, baud);
@@ -2581,49 +2475,27 @@ static unsigned int serial8250_get_divisor(struct uart_port *port,
if (port->get_divisor)
return port->get_divisor(port, baud, frac);
- return serial8250_do_get_divisor(port, baud, frac);
+ return serial8250_do_get_divisor(port, baud);
}
-static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
- tcflag_t c_cflag)
+static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, tcflag_t c_cflag)
{
- unsigned char cval;
-
- switch (c_cflag & CSIZE) {
- case CS5:
- cval = UART_LCR_WLEN5;
- break;
- case CS6:
- cval = UART_LCR_WLEN6;
- break;
- case CS7:
- cval = UART_LCR_WLEN7;
- break;
- default:
- case CS8:
- cval = UART_LCR_WLEN8;
- break;
- }
+ u8 lcr = UART_LCR_WLEN(tty_get_char_size(c_cflag));
if (c_cflag & CSTOPB)
- cval |= UART_LCR_STOP;
- if (c_cflag & PARENB) {
- cval |= UART_LCR_PARITY;
- if (up->bugs & UART_BUG_PARITY)
- up->fifo_bug = true;
- }
+ lcr |= UART_LCR_STOP;
+ if (c_cflag & PARENB)
+ lcr |= UART_LCR_PARITY;
if (!(c_cflag & PARODD))
- cval |= UART_LCR_EPAR;
-#ifdef CMSPAR
+ lcr |= UART_LCR_EPAR;
if (c_cflag & CMSPAR)
- cval |= UART_LCR_SPAR;
-#endif
+ lcr |= UART_LCR_SPAR;
- return cval;
+ return lcr;
}
void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
- unsigned int quot, unsigned int quot_frac)
+ unsigned int quot)
{
struct uart_8250_port *up = up_to_u8250p(port);
@@ -2655,12 +2527,12 @@ static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
if (port->set_divisor)
port->set_divisor(port, baud, quot, quot_frac);
else
- serial8250_do_set_divisor(port, baud, quot, quot_frac);
+ serial8250_do_set_divisor(port, baud, quot);
}
static unsigned int serial8250_get_baud_rate(struct uart_port *port,
struct ktermios *termios,
- struct ktermios *old)
+ const struct ktermios *old)
{
unsigned int tolerance = port->uartclk / 100;
unsigned int min;
@@ -2695,142 +2567,120 @@ static unsigned int serial8250_get_baud_rate(struct uart_port *port,
*/
void serial8250_update_uartclk(struct uart_port *port, unsigned int uartclk)
{
- struct uart_8250_port *up = up_to_u8250p(port);
struct tty_port *tport = &port->state->port;
- unsigned int baud, quot, frac = 0;
- struct ktermios *termios;
- struct tty_struct *tty;
- unsigned long flags;
-
- tty = tty_port_tty_get(tport);
- if (!tty) {
- mutex_lock(&tport->mutex);
- port->uartclk = uartclk;
- mutex_unlock(&tport->mutex);
- return;
- }
- down_write(&tty->termios_rwsem);
- mutex_lock(&tport->mutex);
+ scoped_guard(tty_port_tty, tport) {
+ struct tty_struct *tty = scoped_tty();
- if (port->uartclk == uartclk)
- goto out_unlock;
+ guard(rwsem_write)(&tty->termios_rwsem);
+ guard(mutex)(&tport->mutex);
- port->uartclk = uartclk;
+ if (port->uartclk == uartclk)
+ return;
- if (!tty_port_initialized(tport))
- goto out_unlock;
+ port->uartclk = uartclk;
- termios = &tty->termios;
+ if (!tty_port_initialized(tport))
+ return;
- baud = serial8250_get_baud_rate(port, termios, NULL);
- quot = serial8250_get_divisor(port, baud, &frac);
+ serial8250_do_set_termios(port, &tty->termios, NULL);
- serial8250_rpm_get(up);
- spin_lock_irqsave(&port->lock, flags);
+ return;
+ }
+ guard(mutex)(&tport->mutex);
+ port->uartclk = uartclk;
+}
+EXPORT_SYMBOL_GPL(serial8250_update_uartclk);
- uart_update_timeout(port, termios->c_cflag, baud);
+static void serial8250_set_mini(struct uart_port *port, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
- serial8250_set_divisor(port, baud, quot, frac);
- serial_port_out(port, UART_LCR, up->lcr);
+ if (!(up->capabilities & UART_CAP_MINI))
+ return;
- spin_unlock_irqrestore(&port->lock, flags);
- serial8250_rpm_put(up);
+ termios->c_cflag &= ~(CSTOPB | PARENB | PARODD | CMSPAR);
-out_unlock:
- mutex_unlock(&tport->mutex);
- up_write(&tty->termios_rwsem);
- tty_kref_put(tty);
+ tcflag_t csize = termios->c_cflag & CSIZE;
+ if (csize == CS5 || csize == CS6) {
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= CS7;
+ }
}
-EXPORT_SYMBOL_GPL(serial8250_update_uartclk);
-void
-serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
- struct ktermios *old)
+static void serial8250_set_trigger_for_slow_speed(struct uart_port *port, struct ktermios *termios,
+ unsigned int baud)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned char cval;
- unsigned long flags;
- unsigned int baud, quot, frac = 0;
-
- if (up->capabilities & UART_CAP_MINI) {
- termios->c_cflag &= ~(CSTOPB | PARENB | PARODD | CMSPAR);
- if ((termios->c_cflag & CSIZE) == CS5 ||
- (termios->c_cflag & CSIZE) == CS6)
- termios->c_cflag = (termios->c_cflag & ~CSIZE) | CS7;
- }
- cval = serial8250_compute_lcr(up, termios->c_cflag);
- baud = serial8250_get_baud_rate(port, termios, old);
- quot = serial8250_get_divisor(port, baud, &frac);
+ if (!(up->capabilities & UART_CAP_FIFO))
+ return;
+ if (port->fifosize <= 1)
+ return;
+ if (baud >= 2400)
+ return;
+ if (up->dma)
+ return;
- /*
- * Ok, we're now changing the port state. Do it with
- * interrupts disabled.
- */
- serial8250_rpm_get(up);
- spin_lock_irqsave(&port->lock, flags);
+ up->fcr &= ~UART_FCR_TRIGGER_MASK;
+ up->fcr |= UART_FCR_TRIGGER_1;
+}
- up->lcr = cval; /* Save computed LCR */
+/*
+ * MCR-based auto flow control. When AFE is enabled, RTS will be deasserted when the receive FIFO
+ * contains more characters than the trigger, or the MCR RTS bit is cleared.
+ */
+static void serial8250_set_afe(struct uart_port *port, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
- if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
- /* NOTE: If fifo_bug is not set, a user can set RX_trigger. */
- if ((baud < 2400 && !up->dma) || up->fifo_bug) {
- up->fcr &= ~UART_FCR_TRIGGER_MASK;
- up->fcr |= UART_FCR_TRIGGER_1;
- }
- }
+ if (!(up->capabilities & UART_CAP_AFE))
+ return;
- /*
- * MCR-based auto flow control. When AFE is enabled, RTS will be
- * deasserted when the receive FIFO contains more characters than
- * the trigger, or the MCR RTS bit is cleared.
- */
- if (up->capabilities & UART_CAP_AFE) {
- up->mcr &= ~UART_MCR_AFE;
- if (termios->c_cflag & CRTSCTS)
- up->mcr |= UART_MCR_AFE;
- }
+ up->mcr &= ~UART_MCR_AFE;
+ if (termios->c_cflag & CRTSCTS)
+ up->mcr |= UART_MCR_AFE;
+}
+static void serial8250_set_errors_and_ignores(struct uart_port *port, struct ktermios *termios)
+{
/*
- * Update the per-port timeout.
+ * Specify which conditions may be considered for error handling and the ignoring of
+ * characters. The actual ignoring of characters only occurs if the bit is set in
+ * @ignore_status_mask as well.
*/
- uart_update_timeout(port, termios->c_cflag, baud);
-
- port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+ port->read_status_mask = UART_LSR_OE | UART_LSR_DR;
if (termios->c_iflag & INPCK)
port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
port->read_status_mask |= UART_LSR_BI;
- /*
- * Characteres to ignore
- */
+ /* Characters to ignore */
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= UART_LSR_BI;
/*
- * If we're ignoring parity and break indicators,
- * ignore overruns too (for real raw support).
+ * If we're ignoring parity and break indicators, ignore overruns too (for real raw
+ * support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= UART_LSR_OE;
}
- /*
- * ignore all characters if CREAD is not set
- */
+ /* ignore all characters if CREAD is not set */
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= UART_LSR_DR;
+}
- /*
- * CTS flow control flag and modem status interrupts
- */
+static void serial8250_set_ier(struct uart_port *port, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+
+ /* CTS flow control flag and modem status interrupts */
up->ier &= ~UART_IER_MSI;
- if (!(up->bugs & UART_BUG_NOMSR) &&
- UART_ENABLE_MS(&up->port, termios->c_cflag))
+ if (!(up->bugs & UART_BUG_NOMSR) && UART_ENABLE_MS(&up->port, termios->c_cflag))
up->ier |= UART_IER_MSI;
if (up->capabilities & UART_CAP_UUE)
up->ier |= UART_IER_UUE;
@@ -2838,43 +2688,88 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
up->ier |= UART_IER_RTOIE;
serial_port_out(port, UART_IER, up->ier);
+}
- if (up->capabilities & UART_CAP_EFR) {
- unsigned char efr = 0;
- /*
- * TI16C752/Startech hardware flow control. FIXME:
- * - TI16C752 requires control thresholds to be set.
- * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
- */
- if (termios->c_cflag & CRTSCTS)
- efr |= UART_EFR_CTS;
-
- serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
- if (port->flags & UPF_EXAR_EFR)
- serial_port_out(port, UART_XR_EFR, efr);
- else
- serial_port_out(port, UART_EFR, efr);
- }
+static void serial8250_set_efr(struct uart_port *port, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ u8 efr_reg = UART_EFR;
+ u8 efr = 0;
- serial8250_set_divisor(port, baud, quot, frac);
+ if (!(up->capabilities & UART_CAP_EFR))
+ return;
/*
- * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
- * is written without DLAB set, this mode will be disabled.
+ * TI16C752/Startech hardware flow control. FIXME:
+ * - TI16C752 requires control thresholds to be set.
+ * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
*/
- if (port->type == PORT_16750)
+ if (termios->c_cflag & CRTSCTS)
+ efr |= UART_EFR_CTS;
+
+ if (port->flags & UPF_EXAR_EFR)
+ efr_reg = UART_XR_EFR;
+
+ serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_port_out(port, efr_reg, efr);
+}
+
+static void serial8250_set_fcr(struct uart_port *port, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ bool is_16750 = port->type == PORT_16750;
+
+ if (is_16750)
serial_port_out(port, UART_FCR, up->fcr);
- serial_port_out(port, UART_LCR, up->lcr); /* reset DLAB */
- if (port->type != PORT_16750) {
- /* emulated UARTs (Lucent Venus 167x) need two steps */
- if (up->fcr & UART_FCR_ENABLE_FIFO)
- serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
- serial_port_out(port, UART_FCR, up->fcr); /* set fcr */
+ /*
+ * LCR DLAB must be reset to enable 64-byte FIFO mode. If the FCR is written without DLAB
+ * set, this mode will be disabled.
+ */
+ serial_port_out(port, UART_LCR, up->lcr);
+
+ if (is_16750)
+ return;
+
+ /* emulated UARTs (Lucent Venus 167x) need two steps */
+ if (up->fcr & UART_FCR_ENABLE_FIFO)
+ serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
+
+ serial_port_out(port, UART_FCR, up->fcr);
+}
+
+void
+serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
+ const struct ktermios *old)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int baud, quot, frac = 0;
+ u8 lcr;
+
+ serial8250_set_mini(port, termios);
+ lcr = serial8250_compute_lcr(up, termios->c_cflag);
+ baud = serial8250_get_baud_rate(port, termios, old);
+ quot = serial8250_get_divisor(port, baud, &frac);
+
+ /*
+ * Ok, we're now changing the port state. Do it with interrupts disabled.
+ *
+ * Synchronize UART_IER access against the console.
+ */
+ scoped_guard(serial8250_rpm, up) {
+ guard(uart_port_lock_irqsave)(port);
+
+ up->lcr = lcr;
+ serial8250_set_trigger_for_slow_speed(port, termios, baud);
+ serial8250_set_afe(port, termios);
+ uart_update_timeout(port, termios->c_cflag, baud);
+ serial8250_set_errors_and_ignores(port, termios);
+ serial8250_set_ier(port, termios);
+ serial8250_set_efr(port, termios);
+ serial8250_set_divisor(port, baud, quot, frac);
+ serial8250_set_fcr(port, termios);
+ serial8250_set_mctrl(port, port->mctrl);
}
- serial8250_set_mctrl(port, port->mctrl);
- spin_unlock_irqrestore(&port->lock, flags);
- serial8250_rpm_put(up);
/* Don't rewrite B0 */
if (tty_termios_baud_rate(termios))
@@ -2884,7 +2779,7 @@ EXPORT_SYMBOL(serial8250_do_set_termios);
static void
serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
- struct ktermios *old)
+ const struct ktermios *old)
{
if (port->set_termios)
port->set_termios(port, termios, old);
@@ -2896,15 +2791,13 @@ void serial8250_do_set_ldisc(struct uart_port *port, struct ktermios *termios)
{
if (termios->c_line == N_PPS) {
port->flags |= UPF_HARDPPS_CD;
- spin_lock_irq(&port->lock);
+ guard(uart_port_lock_irq)(port);
serial8250_enable_ms(port);
- spin_unlock_irq(&port->lock);
} else {
port->flags &= ~UPF_HARDPPS_CD;
if (!UART_ENABLE_MS(port, termios->c_cflag)) {
- spin_lock_irq(&port->lock);
+ guard(uart_port_lock_irq)(port);
serial8250_disable_ms(port);
- spin_unlock_irq(&port->lock);
}
}
}
@@ -2942,11 +2835,6 @@ static unsigned int serial8250_port_size(struct uart_8250_port *pt)
{
if (pt->port.mapsize)
return pt->port.mapsize;
- if (pt->port.iotype == UPIO_AU) {
- if (pt->port.type == PORT_RT2880)
- return 0x100;
- return 0x1000;
- }
if (is_omap1_8250(pt))
return 0x16 << pt->port.regshift;
@@ -2960,7 +2848,6 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
{
unsigned int size = serial8250_port_size(up);
struct uart_port *port = &up->port;
- int ret = 0;
switch (port->iotype) {
case UPIO_AU:
@@ -2970,29 +2857,29 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
case UPIO_MEM16:
case UPIO_MEM:
if (!port->mapbase)
- break;
+ return -EINVAL;
- if (!request_mem_region(port->mapbase, size, "serial")) {
- ret = -EBUSY;
- break;
- }
+ if (!request_mem_region(port->mapbase, size, "serial"))
+ return -EBUSY;
if (port->flags & UPF_IOREMAP) {
port->membase = ioremap(port->mapbase, size);
if (!port->membase) {
release_mem_region(port->mapbase, size);
- ret = -ENOMEM;
+ return -ENOMEM;
}
}
- break;
-
+ return 0;
case UPIO_HUB6:
case UPIO_PORT:
if (!request_region(port->iobase, size, "serial"))
- ret = -EBUSY;
+ return -EBUSY;
+ return 0;
+ case UPIO_UNKNOWN:
break;
}
- return ret;
+
+ return 0;
}
static void serial8250_release_std_resource(struct uart_8250_port *up)
@@ -3022,6 +2909,8 @@ static void serial8250_release_std_resource(struct uart_8250_port *up)
case UPIO_PORT:
release_region(port->iobase, size);
break;
+ case UPIO_UNKNOWN:
+ break;
}
}
@@ -3109,8 +2998,7 @@ static int do_set_rxtrig(struct tty_port *port, unsigned char bytes)
struct uart_8250_port *up = up_to_u8250p(uport);
int rxtrig;
- if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 ||
- up->fifo_bug)
+ if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1)
return -EINVAL;
rxtrig = bytes_to_fcr_rxtrig(up, bytes);
@@ -3194,13 +3082,6 @@ static void serial8250_config_port(struct uart_port *port, int flags)
if (flags & UART_CONFIG_TYPE)
autoconfig(up);
- if (port->rs485.flags & SER_RS485_ENABLED)
- port->rs485_config(port, &port->rs485);
-
- /* if access method is AU, it is a 16550 with a quirk */
- if (port->type == PORT_16550A && port->iotype == UPIO_AU)
- up->bugs |= UART_BUG_NOMSR;
-
/* HW bugs may trigger IRQ while IIR == NO_INT */
if (port->type == PORT_TEGRA)
up->bugs |= UART_BUG_NOMSR;
@@ -3218,7 +3099,7 @@ static void serial8250_config_port(struct uart_port *port, int flags)
static int
serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
{
- if (ser->irq >= nr_irqs || ser->irq < 0 ||
+ if (ser->irq >= irq_get_nr_irqs() || ser->irq < 0 ||
ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
ser->type == PORT_STARTECH)
@@ -3248,6 +3129,7 @@ static const struct uart_ops serial8250_pops = {
.break_ctl = serial8250_break_ctl,
.startup = serial8250_startup,
.shutdown = serial8250_shutdown,
+ .flush_buffer = serial8250_flush_buffer,
.set_termios = serial8250_set_termios,
.set_ldisc = serial8250_set_ldisc,
.pm = serial8250_pm,
@@ -3267,10 +3149,12 @@ void serial8250_init_port(struct uart_8250_port *up)
struct uart_port *port = &up->port;
spin_lock_init(&port->lock);
+ port->ctrl_id = 0;
+ port->pm = NULL;
port->ops = &serial8250_pops;
port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE);
- up->cur_iotype = 0xFF;
+ up->cur_iotype = UPIO_UNKNOWN;
}
EXPORT_SYMBOL_GPL(serial8250_init_port);
@@ -3303,12 +3187,17 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
#ifdef CONFIG_SERIAL_8250_CONSOLE
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar(struct uart_port *port, unsigned char ch)
+{
+ serial_port_out(port, UART_TX, ch);
+}
+
+static void serial8250_console_wait_putchar(struct uart_port *port, unsigned char ch)
{
struct uart_8250_port *up = up_to_u8250p(port);
wait_for_xmitr(up, UART_LSR_THRE);
- serial_port_out(port, UART_TX, ch);
+ serial8250_console_putchar(port, ch);
}
/*
@@ -3321,15 +3210,30 @@ static void serial8250_console_restore(struct uart_8250_port *up)
unsigned int baud, quot, frac = 0;
termios.c_cflag = port->cons->cflag;
- if (port->state->port.tty && termios.c_cflag == 0)
+ termios.c_ispeed = port->cons->ispeed;
+ termios.c_ospeed = port->cons->ospeed;
+ if (port->state->port.tty && termios.c_cflag == 0) {
termios.c_cflag = port->state->port.tty->termios.c_cflag;
+ termios.c_ispeed = port->state->port.tty->termios.c_ispeed;
+ termios.c_ospeed = port->state->port.tty->termios.c_ospeed;
+ }
baud = serial8250_get_baud_rate(port, &termios, NULL);
quot = serial8250_get_divisor(port, baud, &frac);
serial8250_set_divisor(port, baud, quot, frac);
serial_port_out(port, UART_LCR, up->lcr);
- serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
+ serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
+}
+
+static void fifo_wait_for_lsr(struct uart_8250_port *up, unsigned int count)
+{
+ unsigned int i;
+
+ for (i = 0; i < count; i++) {
+ if (wait_for_lsr(up, UART_LSR_THRE))
+ return;
+ }
}
/*
@@ -3341,24 +3245,34 @@ static void serial8250_console_restore(struct uart_8250_port *up)
static void serial8250_console_fifo_write(struct uart_8250_port *up,
const char *s, unsigned int count)
{
- int i;
const char *end = s + count;
- unsigned int fifosize = up->port.fifosize;
+ unsigned int fifosize = up->tx_loadsz;
+ struct uart_port *port = &up->port;
+ unsigned int tx_count = 0;
bool cr_sent = false;
+ unsigned int i;
while (s != end) {
- wait_for_lsr(up, UART_LSR_THRE);
+ /* Allow timeout for each byte of a possibly full FIFO */
+ fifo_wait_for_lsr(up, fifosize);
for (i = 0; i < fifosize && s != end; ++i) {
if (*s == '\n' && !cr_sent) {
- serial_out(up, UART_TX, '\r');
+ serial8250_console_putchar(port, '\r');
cr_sent = true;
} else {
- serial_out(up, UART_TX, *s++);
+ serial8250_console_putchar(port, *s++);
cr_sent = false;
}
}
+ tx_count = i;
}
+
+ /*
+ * Allow timeout for each byte written since the caller will only wait
+ * for UART_LSR_BOTH_EMPTY using the timeout of a single character
+ */
+ fifo_wait_for_lsr(up, tx_count);
}
/*
@@ -3382,19 +3296,15 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
touch_nmi_watchdog();
if (oops_in_progress)
- locked = spin_trylock_irqsave(&port->lock, flags);
+ locked = uart_port_trylock_irqsave(port, &flags);
else
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
/*
* First save the IER then disable the interrupts
*/
ier = serial_port_in(port, UART_IER);
-
- if (up->capabilities & UART_CAP_UUE)
- serial_port_out(port, UART_IER, UART_IER_UUE);
- else
- serial_port_out(port, UART_IER, 0);
+ serial8250_clear_IER(up);
/* check scratch reg to see if port powered off during system sleep */
if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
@@ -3404,13 +3314,23 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
if (em485) {
if (em485->tx_stopped)
- up->rs485_start_tx(up);
+ up->rs485_start_tx(up, false);
mdelay(port->rs485.delay_rts_before_send);
}
use_fifo = (up->capabilities & UART_CAP_FIFO) &&
- port->fifosize > 1 &&
- (serial_port_in(port, UART_FCR) & UART_FCR_ENABLE_FIFO) &&
+ /*
+ * BCM283x requires to check the fifo
+ * after each byte.
+ */
+ !(up->capabilities & UART_CAP_MINI) &&
+ /*
+ * tx_loadsz contains the transmit fifo size
+ */
+ up->tx_loadsz > 1 &&
+ (up->fcr & UART_FCR_ENABLE_FIFO) &&
+ port->state &&
+ test_bit(TTY_PORT_INITIALIZED, &port->state->port.iflags) &&
/*
* After we put a data in the fifo, the controller will send
* it regardless of the CTS state. Therefore, only use fifo
@@ -3421,18 +3341,18 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
if (likely(use_fifo))
serial8250_console_fifo_write(up, s, count);
else
- uart_console_write(port, s, count, serial8250_console_putchar);
+ uart_console_write(port, s, count, serial8250_console_wait_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore the IER
*/
- wait_for_xmitr(up, BOTH_EMPTY);
+ wait_for_xmitr(up, UART_LSR_BOTH_EMPTY);
if (em485) {
mdelay(port->rs485.delay_rts_after_send);
if (em485->tx_stopped)
- up->rs485_stop_tx(up);
+ up->rs485_stop_tx(up, false);
}
serial_port_out(port, UART_IER, ier);
@@ -3448,7 +3368,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
serial8250_modem_status(up);
if (locked)
- spin_unlock_irqrestore(&port->lock, flags);
+ uart_port_unlock_irqrestore(port, flags);
}
static unsigned int probe_baud(struct uart_port *port)
@@ -3502,4 +3422,5 @@ int serial8250_console_exit(struct uart_port *port)
#endif /* CONFIG_SERIAL_8250_CONSOLE */
+MODULE_DESCRIPTION("Base port operations for 8250/16550-type serial ports");
MODULE_LICENSE("GPL");