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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.c298
1 files changed, 122 insertions, 176 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 2da9db960d09..719faf92aa8a 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -508,20 +508,22 @@ void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p)
}
EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos);
-static void serial8250_rpm_get(struct uart_8250_port *p)
+void serial8250_rpm_get(struct uart_8250_port *p)
{
if (!(p->capabilities & UART_CAP_RPM))
return;
pm_runtime_get_sync(p->port.dev);
}
+EXPORT_SYMBOL_GPL(serial8250_rpm_get);
-static void serial8250_rpm_put(struct uart_8250_port *p)
+void serial8250_rpm_put(struct uart_8250_port *p)
{
if (!(p->capabilities & UART_CAP_RPM))
return;
pm_runtime_mark_last_busy(p->port.dev);
pm_runtime_put_autosuspend(p->port.dev);
}
+EXPORT_SYMBOL_GPL(serial8250_rpm_put);
/**
* serial8250_em485_init() - put uart_8250_port into rs485 emulating
@@ -672,28 +674,27 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
{
unsigned char lcr = 0, efr = 0;
- serial8250_rpm_get(p);
-
- if (p->capabilities & UART_CAP_SLEEP) {
- /* Synchronize UART_IER access against the console. */
- uart_port_lock_irq(&p->port);
- 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);
- }
- uart_port_unlock_irq(&p->port);
- }
+ guard(serial8250_rpm)(p);
+
+ if (!(p->capabilities & UART_CAP_SLEEP))
+ return;
+
+ /* Synchronize UART_IER access against the console. */
+ guard(uart_port_lock_irq)(&p->port);
- serial8250_rpm_put(p);
+ 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);
+ }
}
/* Clear the interrupt registers. */
@@ -1229,9 +1230,8 @@ static void autoconfig_irq(struct uart_8250_port *up)
probe_irq_off(probe_irq_on());
save_mcr = serial8250_in_MCR(up);
/* Synchronize UART_IER access against the console. */
- uart_port_lock_irq(port);
- save_ier = serial_in(up, UART_IER);
- uart_port_unlock_irq(port);
+ 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();
@@ -1244,9 +1244,8 @@ static void autoconfig_irq(struct uart_8250_port *up)
UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
}
/* Synchronize UART_IER access against the console. */
- uart_port_lock_irq(port);
- serial_out(up, UART_IER, UART_IER_ALL_INTR);
- uart_port_unlock_irq(port);
+ 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);
@@ -1254,9 +1253,8 @@ static void autoconfig_irq(struct uart_8250_port *up)
serial8250_out_MCR(up, save_mcr);
/* Synchronize UART_IER access against the console. */
- uart_port_lock_irq(port);
- serial_out(up, UART_IER, save_ier);
- uart_port_unlock_irq(port);
+ scoped_guard(uart_port_lock_irq, port)
+ serial_out(up, UART_IER, save_ier);
if (port->flags & UPF_FOURPORT)
outb_p(save_ICP, ICP);
@@ -1271,12 +1269,10 @@ static void serial8250_stop_rx(struct uart_port *port)
/* Port locked to synchronize UART_IER access against the console. */
lockdep_assert_held_once(&port->lock);
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
serial_port_out(port, UART_IER, up->ier);
-
- serial8250_rpm_put(up);
}
/**
@@ -1320,17 +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);
- uart_port_lock_irqsave(&p->port, &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, true);
em485->active_timer = NULL;
em485->tx_stopped = true;
}
- uart_port_unlock_irqrestore(&p->port, flags);
- serial8250_rpm_put(p);
return HRTIMER_NORESTART;
}
@@ -1405,7 +1399,7 @@ 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);
/*
@@ -1415,7 +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)
@@ -1510,14 +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;
- uart_port_lock_irqsave(&p->port, &flags);
+ guard(uart_port_lock_irqsave)(&p->port);
+
if (em485->active_timer == &em485->start_tx_timer) {
__start_tx(&p->port);
em485->active_timer = NULL;
}
- uart_port_unlock_irqrestore(&p->port, flags);
return HRTIMER_NORESTART;
}
@@ -1585,9 +1577,8 @@ 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, u16 lsr)
@@ -1848,15 +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);
}
/*
@@ -1867,16 +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);
- uart_port_lock_irqsave(port, &flags);
+ guard(uart_port_lock_irqsave)(port);
serial8250_tx_chars(up);
- uart_port_unlock_irqrestore(port, flags);
}
iir = serial_port_in(port, UART_IIR);
@@ -1886,19 +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 int result = 0;
- unsigned long flags;
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
+ guard(uart_port_lock_irqsave)(port);
- uart_port_lock_irqsave(port, &flags);
if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
- result = TIOCSER_TEMT;
- uart_port_unlock_irqrestore(port, flags);
-
- serial8250_rpm_put(up);
+ return TIOCSER_TEMT;
- return result;
+ return 0;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
@@ -1907,9 +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)
@@ -1953,17 +1932,15 @@ 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);
- uart_port_lock_irqsave(port, &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);
- uart_port_unlock_irqrestore(port, flags);
- serial8250_rpm_put(up);
}
/* Returns true if @bits were set, false on timeout */
@@ -2023,22 +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);
- 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);
}
@@ -2056,7 +2026,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
* should allow safe lockless usage here.
*/
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
/*
* First save the IER then disable the interrupts
*/
@@ -2075,7 +2045,6 @@ static void serial8250_put_poll_char(struct uart_port *port,
*/
wait_for_xmitr(up, UART_LSR_BOTH_EMPTY);
serial_port_out(port, UART_IER, ier);
- serial8250_rpm_put(up);
}
#endif /* CONFIG_CONSOLE_POLL */
@@ -2083,16 +2052,15 @@ static void serial8250_put_poll_char(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;
switch (port->type) {
- case PORT_16C950:
+ case PORT_16C950: {
/*
* Wake up and initialize UART
*
* Synchronize UART_IER access against the console.
*/
- uart_port_lock_irqsave(port, &flags);
+ 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);
@@ -2102,18 +2070,18 @@ static void serial8250_startup_special(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);
- uart_port_unlock_irqrestore(port, flags);
break;
+ }
case PORT_DA830:
/*
* Reset the port
*
* Synchronize UART_IER access against the console.
*/
- uart_port_lock_irqsave(port, &flags);
- serial_port_out(port, UART_IER, 0);
- serial_port_out(port, UART_DA830_PWREMU_MGMT, 0);
- uart_port_unlock_irqrestore(port, flags);
+ 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 */
@@ -2171,7 +2139,6 @@ static void serial8250_set_TRG_levels(struct uart_port *port)
static void serial8250_THRE_test(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned long flags;
bool iir_noint1, iir_noint2;
if (!port->irq)
@@ -2191,19 +2158,17 @@ static void serial8250_THRE_test(struct uart_port *port)
*
* Synchronize UART_IER access against the console.
*/
- uart_port_lock_irqsave(port, &flags);
-
- wait_for_xmitr(up, UART_LSR_THRE);
- serial_port_out_sync(port, UART_IER, UART_IER_THRI);
- udelay(1); /* allow THRE to set */
- 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_noint2 = serial_port_in(port, UART_IIR) & UART_IIR_NO_INT;
- serial_port_out(port, UART_IER, 0);
-
- uart_port_unlock_irqrestore(port, flags);
+ 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 */
+ 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_noint2 = serial_port_in(port, UART_IIR) & UART_IIR_NO_INT;
+ serial_port_out(port, UART_IER, 0);
+ }
if (port->irqflags & IRQF_SHARED)
enable_irq(port->irq);
@@ -2267,14 +2232,11 @@ static void serial8250_iir_txen_test(struct uart_port *port)
static void serial8250_initialize(struct uart_port *port)
{
- unsigned long flags;
-
- uart_port_lock_irqsave(port, &flags);
+ guard(uart_port_lock_irqsave)(port);
serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
serial8250_init_mctrl(port);
serial8250_iir_txen_test(port);
- uart_port_unlock_irqrestore(port, flags);
}
int serial8250_do_startup(struct uart_port *port)
@@ -2293,7 +2255,7 @@ int serial8250_do_startup(struct uart_port *port)
if (port->iotype != up->cur_iotype)
set_io_from_upio(port);
- serial8250_rpm_get(up);
+ guard(serial8250_rpm)(up);
serial8250_startup_special(port);
@@ -2313,8 +2275,7 @@ int serial8250_do_startup(struct uart_port *port)
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;
+ return -ENODEV;
}
serial8250_set_TRG_levels(port);
@@ -2325,7 +2286,7 @@ int serial8250_do_startup(struct uart_port *port)
retval = up->ops->setup_irq(up);
if (retval)
- goto out;
+ return retval;
serial8250_THRE_test(port);
@@ -2374,10 +2335,8 @@ int serial8250_do_startup(struct uart_port *port)
outb_p(0x80, icp);
inb_p(icp);
}
- retval = 0;
-out:
- serial8250_rpm_put(up);
- return retval;
+
+ return 0;
}
EXPORT_SYMBOL_GPL(serial8250_do_startup);
@@ -2391,7 +2350,6 @@ 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);
/*
@@ -2399,26 +2357,26 @@ void serial8250_do_shutdown(struct uart_port *port)
*
* Synchronize UART_IER access against the console.
*/
- uart_port_lock_irqsave(port, &flags);
- up->ier = 0;
- serial_port_out(port, UART_IER, 0);
- uart_port_unlock_irqrestore(port, 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);
- uart_port_lock_irqsave(port, &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);
- uart_port_unlock_irqrestore(port, flags);
+ serial8250_set_mctrl(port, port->mctrl);
+ }
/*
* Disable break condition and FIFOs
@@ -2610,33 +2568,27 @@ static unsigned int serial8250_get_baud_rate(struct uart_port *port,
void serial8250_update_uartclk(struct uart_port *port, unsigned int uartclk)
{
struct tty_port *tport = &port->state->port;
- struct tty_struct *tty;
- tty = tty_port_tty_get(tport);
- if (!tty) {
- mutex_lock(&tport->mutex);
- port->uartclk = uartclk;
- mutex_unlock(&tport->mutex);
- return;
- }
+ scoped_guard(tty_port_tty, tport) {
+ struct tty_struct *tty = scoped_tty();
- down_write(&tty->termios_rwsem);
- mutex_lock(&tport->mutex);
+ guard(rwsem_write)(&tty->termios_rwsem);
+ guard(mutex)(&tport->mutex);
- if (port->uartclk == uartclk)
- goto out_unlock;
+ if (port->uartclk == uartclk)
+ return;
- port->uartclk = uartclk;
+ port->uartclk = uartclk;
- if (!tty_port_initialized(tport))
- goto out_unlock;
+ if (!tty_port_initialized(tport))
+ return;
- serial8250_do_set_termios(port, &tty->termios, NULL);
+ serial8250_do_set_termios(port, &tty->termios, NULL);
-out_unlock:
- mutex_unlock(&tport->mutex);
- up_write(&tty->termios_rwsem);
- tty_kref_put(tty);
+ return;
+ }
+ guard(mutex)(&tport->mutex);
+ port->uartclk = uartclk;
}
EXPORT_SYMBOL_GPL(serial8250_update_uartclk);
@@ -2791,7 +2743,6 @@ 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 long flags;
unsigned int baud, quot, frac = 0;
u8 lcr;
@@ -2801,27 +2752,24 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
quot = serial8250_get_divisor(port, baud, &frac);
/*
- * Ok, we're now changing the port state. Do it with
- * interrupts disabled.
+ * Ok, we're now changing the port state. Do it with interrupts disabled.
*
* Synchronize UART_IER access against the console.
*/
- serial8250_rpm_get(up);
- uart_port_lock_irqsave(port, &flags);
-
- 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);
+ scoped_guard(serial8250_rpm, up) {
+ guard(uart_port_lock_irqsave)(port);
- uart_port_unlock_irqrestore(port, flags);
- serial8250_rpm_put(up);
+ 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);
+ }
/* Don't rewrite B0 */
if (tty_termios_baud_rate(termios))
@@ -2843,15 +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;
- uart_port_lock_irq(port);
+ guard(uart_port_lock_irq)(port);
serial8250_enable_ms(port);
- uart_port_unlock_irq(port);
} else {
port->flags &= ~UPF_HARDPPS_CD;
if (!UART_ENABLE_MS(port, termios->c_cflag)) {
- uart_port_lock_irq(port);
+ guard(uart_port_lock_irq)(port);
serial8250_disable_ms(port);
- uart_port_unlock_irq(port);
}
}
}
generated by cgit (git 2.34.1) at 2025-10-06 00:09:44 +0000