diff options
Diffstat (limited to 'drivers/tty/serial/sc16is7xx.c')
| -rw-r--r-- | drivers/tty/serial/sc16is7xx.c | 600 |
1 files changed, 266 insertions, 334 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index 929206a9a6e1..7b51cdc274fd 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -1,35 +1,40 @@ // SPDX-License-Identifier: GPL-2.0+ /* - * SC16IS7xx tty serial driver - Copyright (C) 2014 GridPoint - * Author: Jon Ringle <jringle@gridpoint.com> + * SC16IS7xx tty serial driver - common code * - * Based on max310x.c, by Alexander Shiyan <shc_work@mail.ru> + * Copyright (C) 2014 GridPoint + * Author: Jon Ringle <jringle@gridpoint.com> + * Based on max310x.c, by Alexander Shiyan <shc_work@mail.ru> */ -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#undef DEFAULT_SYMBOL_NAMESPACE +#define DEFAULT_SYMBOL_NAMESPACE "SERIAL_NXP_SC16IS7XX" -#include <linux/bitops.h> +#include <linux/bits.h> #include <linux/clk.h> #include <linux/delay.h> #include <linux/device.h> +#include <linux/export.h> +#include <linux/gpio/consumer.h> #include <linux/gpio/driver.h> -#include <linux/i2c.h> +#include <linux/idr.h> +#include <linux/kthread.h> #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/property.h> #include <linux/regmap.h> +#include <linux/sched.h> #include <linux/serial_core.h> #include <linux/serial.h> +#include <linux/string.h> #include <linux/tty.h> #include <linux/tty_flip.h> -#include <linux/spi/spi.h> #include <linux/uaccess.h> #include <linux/units.h> -#include <uapi/linux/sched/types.h> -#define SC16IS7XX_NAME "sc16is7xx" +#include "sc16is7xx.h" + #define SC16IS7XX_MAX_DEVS 8 -#define SC16IS7XX_MAX_PORTS 2 /* Maximum number of UART ports per IC. */ /* SC16IS7XX register definitions */ #define SC16IS7XX_RHR_REG (0x00) /* RX FIFO */ @@ -74,52 +79,52 @@ #define SC16IS7XX_XOFF2_REG (0x07) /* Xoff2 word */ /* IER register bits */ -#define SC16IS7XX_IER_RDI_BIT (1 << 0) /* Enable RX data interrupt */ -#define SC16IS7XX_IER_THRI_BIT (1 << 1) /* Enable TX holding register +#define SC16IS7XX_IER_RDI_BIT BIT(0) /* Enable RX data interrupt */ +#define SC16IS7XX_IER_THRI_BIT BIT(1) /* Enable TX holding register * interrupt */ -#define SC16IS7XX_IER_RLSI_BIT (1 << 2) /* Enable RX line status +#define SC16IS7XX_IER_RLSI_BIT BIT(2) /* Enable RX line status * interrupt */ -#define SC16IS7XX_IER_MSI_BIT (1 << 3) /* Enable Modem status +#define SC16IS7XX_IER_MSI_BIT BIT(3) /* Enable Modem status * interrupt */ /* IER register bits - write only if (EFR[4] == 1) */ -#define SC16IS7XX_IER_SLEEP_BIT (1 << 4) /* Enable Sleep mode */ -#define SC16IS7XX_IER_XOFFI_BIT (1 << 5) /* Enable Xoff interrupt */ -#define SC16IS7XX_IER_RTSI_BIT (1 << 6) /* Enable nRTS interrupt */ -#define SC16IS7XX_IER_CTSI_BIT (1 << 7) /* Enable nCTS interrupt */ +#define SC16IS7XX_IER_SLEEP_BIT BIT(4) /* Enable Sleep mode */ +#define SC16IS7XX_IER_XOFFI_BIT BIT(5) /* Enable Xoff interrupt */ +#define SC16IS7XX_IER_RTSI_BIT BIT(6) /* Enable nRTS interrupt */ +#define SC16IS7XX_IER_CTSI_BIT BIT(7) /* Enable nCTS interrupt */ /* FCR register bits */ -#define SC16IS7XX_FCR_FIFO_BIT (1 << 0) /* Enable FIFO */ -#define SC16IS7XX_FCR_RXRESET_BIT (1 << 1) /* Reset RX FIFO */ -#define SC16IS7XX_FCR_TXRESET_BIT (1 << 2) /* Reset TX FIFO */ -#define SC16IS7XX_FCR_RXLVLL_BIT (1 << 6) /* RX Trigger level LSB */ -#define SC16IS7XX_FCR_RXLVLH_BIT (1 << 7) /* RX Trigger level MSB */ +#define SC16IS7XX_FCR_FIFO_BIT BIT(0) /* Enable FIFO */ +#define SC16IS7XX_FCR_RXRESET_BIT BIT(1) /* Reset RX FIFO */ +#define SC16IS7XX_FCR_TXRESET_BIT BIT(2) /* Reset TX FIFO */ +#define SC16IS7XX_FCR_RXLVLL_BIT BIT(6) /* RX Trigger level LSB */ +#define SC16IS7XX_FCR_RXLVLH_BIT BIT(7) /* RX Trigger level MSB */ /* FCR register bits - write only if (EFR[4] == 1) */ -#define SC16IS7XX_FCR_TXLVLL_BIT (1 << 4) /* TX Trigger level LSB */ -#define SC16IS7XX_FCR_TXLVLH_BIT (1 << 5) /* TX Trigger level MSB */ +#define SC16IS7XX_FCR_TXLVLL_BIT BIT(4) /* TX Trigger level LSB */ +#define SC16IS7XX_FCR_TXLVLH_BIT BIT(5) /* TX Trigger level MSB */ /* IIR register bits */ -#define SC16IS7XX_IIR_NO_INT_BIT (1 << 0) /* No interrupts pending */ -#define SC16IS7XX_IIR_ID_MASK 0x3e /* Mask for the interrupt ID */ -#define SC16IS7XX_IIR_THRI_SRC 0x02 /* TX holding register empty */ -#define SC16IS7XX_IIR_RDI_SRC 0x04 /* RX data interrupt */ -#define SC16IS7XX_IIR_RLSE_SRC 0x06 /* RX line status error */ -#define SC16IS7XX_IIR_RTOI_SRC 0x0c /* RX time-out interrupt */ -#define SC16IS7XX_IIR_MSI_SRC 0x00 /* Modem status interrupt - * - only on 75x/76x - */ -#define SC16IS7XX_IIR_INPIN_SRC 0x30 /* Input pin change of state - * - only on 75x/76x - */ -#define SC16IS7XX_IIR_XOFFI_SRC 0x10 /* Received Xoff */ -#define SC16IS7XX_IIR_CTSRTS_SRC 0x20 /* nCTS,nRTS change of state - * from active (LOW) - * to inactive (HIGH) - */ +#define SC16IS7XX_IIR_NO_INT_BIT 0x01 /* No interrupts pending */ +#define SC16IS7XX_IIR_ID_MASK GENMASK(5, 1) /* Mask for the interrupt ID */ +#define SC16IS7XX_IIR_THRI_SRC 0x02 /* TX holding register empty */ +#define SC16IS7XX_IIR_RDI_SRC 0x04 /* RX data interrupt */ +#define SC16IS7XX_IIR_RLSE_SRC 0x06 /* RX line status error */ +#define SC16IS7XX_IIR_RTOI_SRC 0x0c /* RX time-out interrupt */ +#define SC16IS7XX_IIR_MSI_SRC 0x00 /* Modem status interrupt + * - only on 75x/76x + */ +#define SC16IS7XX_IIR_INPIN_SRC 0x30 /* Input pin change of state + * - only on 75x/76x + */ +#define SC16IS7XX_IIR_XOFFI_SRC 0x10 /* Received Xoff */ +#define SC16IS7XX_IIR_CTSRTS_SRC 0x20 /* nCTS,nRTS change of state + * from active (LOW) + * to inactive (HIGH) + */ /* LCR register bits */ -#define SC16IS7XX_LCR_LENGTH0_BIT (1 << 0) /* Word length bit 0 */ -#define SC16IS7XX_LCR_LENGTH1_BIT (1 << 1) /* Word length bit 1 +#define SC16IS7XX_LCR_LENGTH0_BIT BIT(0) /* Word length bit 0 */ +#define SC16IS7XX_LCR_LENGTH1_BIT BIT(1) /* Word length bit 1 * * Word length bits table: * 00 -> 5 bit words @@ -127,7 +132,7 @@ * 10 -> 7 bit words * 11 -> 8 bit words */ -#define SC16IS7XX_LCR_STOPLEN_BIT (1 << 2) /* STOP length bit +#define SC16IS7XX_LCR_STOPLEN_BIT BIT(2) /* STOP length bit * * STOP length bit table: * 0 -> 1 stop bit @@ -135,11 +140,11 @@ * word length is 5, * 2 stop bits otherwise */ -#define SC16IS7XX_LCR_PARITY_BIT (1 << 3) /* Parity bit enable */ -#define SC16IS7XX_LCR_EVENPARITY_BIT (1 << 4) /* Even parity bit enable */ -#define SC16IS7XX_LCR_FORCEPARITY_BIT (1 << 5) /* 9-bit multidrop parity */ -#define SC16IS7XX_LCR_TXBREAK_BIT (1 << 6) /* TX break enable */ -#define SC16IS7XX_LCR_DLAB_BIT (1 << 7) /* Divisor Latch enable */ +#define SC16IS7XX_LCR_PARITY_BIT BIT(3) /* Parity bit enable */ +#define SC16IS7XX_LCR_EVENPARITY_BIT BIT(4) /* Even parity bit enable */ +#define SC16IS7XX_LCR_FORCEPARITY_BIT BIT(5) /* 9-bit multidrop parity */ +#define SC16IS7XX_LCR_TXBREAK_BIT BIT(6) /* TX break enable */ +#define SC16IS7XX_LCR_DLAB_BIT BIT(7) /* Divisor Latch enable */ #define SC16IS7XX_LCR_WORD_LEN_5 (0x00) #define SC16IS7XX_LCR_WORD_LEN_6 (0x01) #define SC16IS7XX_LCR_WORD_LEN_7 (0x02) @@ -150,61 +155,65 @@ * reg set */ /* MCR register bits */ -#define SC16IS7XX_MCR_DTR_BIT (1 << 0) /* DTR complement +#define SC16IS7XX_MCR_DTR_BIT BIT(0) /* DTR complement * - only on 75x/76x */ -#define SC16IS7XX_MCR_RTS_BIT (1 << 1) /* RTS complement */ -#define SC16IS7XX_MCR_TCRTLR_BIT (1 << 2) /* TCR/TLR register enable */ -#define SC16IS7XX_MCR_LOOP_BIT (1 << 4) /* Enable loopback test mode */ -#define SC16IS7XX_MCR_XONANY_BIT (1 << 5) /* Enable Xon Any +#define SC16IS7XX_MCR_RTS_BIT BIT(1) /* RTS complement */ +#define SC16IS7XX_MCR_TCRTLR_BIT BIT(2) /* TCR/TLR register enable */ +#define SC16IS7XX_MCR_LOOP_BIT BIT(4) /* Enable loopback test mode */ +#define SC16IS7XX_MCR_XONANY_BIT BIT(5) /* Enable Xon Any * - write enabled * if (EFR[4] == 1) */ -#define SC16IS7XX_MCR_IRDA_BIT (1 << 6) /* Enable IrDA mode +#define SC16IS7XX_MCR_IRDA_BIT BIT(6) /* Enable IrDA mode * - write enabled * if (EFR[4] == 1) */ -#define SC16IS7XX_MCR_CLKSEL_BIT (1 << 7) /* Divide clock by 4 +#define SC16IS7XX_MCR_CLKSEL_BIT BIT(7) /* Divide clock by 4 * - write enabled * if (EFR[4] == 1) */ /* LSR register bits */ -#define SC16IS7XX_LSR_DR_BIT (1 << 0) /* Receiver data ready */ -#define SC16IS7XX_LSR_OE_BIT (1 << 1) /* Overrun Error */ -#define SC16IS7XX_LSR_PE_BIT (1 << 2) /* Parity Error */ -#define SC16IS7XX_LSR_FE_BIT (1 << 3) /* Frame Error */ -#define SC16IS7XX_LSR_BI_BIT (1 << 4) /* Break Interrupt */ -#define SC16IS7XX_LSR_BRK_ERROR_MASK 0x1E /* BI, FE, PE, OE bits */ -#define SC16IS7XX_LSR_THRE_BIT (1 << 5) /* TX holding register empty */ -#define SC16IS7XX_LSR_TEMT_BIT (1 << 6) /* Transmitter empty */ -#define SC16IS7XX_LSR_FIFOE_BIT (1 << 7) /* Fifo Error */ +#define SC16IS7XX_LSR_DR_BIT BIT(0) /* Receiver data ready */ +#define SC16IS7XX_LSR_OE_BIT BIT(1) /* Overrun Error */ +#define SC16IS7XX_LSR_PE_BIT BIT(2) /* Parity Error */ +#define SC16IS7XX_LSR_FE_BIT BIT(3) /* Frame Error */ +#define SC16IS7XX_LSR_BI_BIT BIT(4) /* Break Interrupt */ +#define SC16IS7XX_LSR_BRK_ERROR_MASK \ + (SC16IS7XX_LSR_OE_BIT | \ + SC16IS7XX_LSR_PE_BIT | \ + SC16IS7XX_LSR_FE_BIT | \ + SC16IS7XX_LSR_BI_BIT) + +#define SC16IS7XX_LSR_THRE_BIT BIT(5) /* TX holding register empty */ +#define SC16IS7XX_LSR_TEMT_BIT BIT(6) /* Transmitter empty */ +#define SC16IS7XX_LSR_FIFOE_BIT BIT(7) /* Fifo Error */ /* MSR register bits */ -#define SC16IS7XX_MSR_DCTS_BIT (1 << 0) /* Delta CTS Clear To Send */ -#define SC16IS7XX_MSR_DDSR_BIT (1 << 1) /* Delta DSR Data Set Ready +#define SC16IS7XX_MSR_DCTS_BIT BIT(0) /* Delta CTS Clear To Send */ +#define SC16IS7XX_MSR_DDSR_BIT BIT(1) /* Delta DSR Data Set Ready * or (IO4) * - only on 75x/76x */ -#define SC16IS7XX_MSR_DRI_BIT (1 << 2) /* Delta RI Ring Indicator +#define SC16IS7XX_MSR_DRI_BIT BIT(2) /* Delta RI Ring Indicator * or (IO7) * - only on 75x/76x */ -#define SC16IS7XX_MSR_DCD_BIT (1 << 3) /* Delta CD Carrier Detect +#define SC16IS7XX_MSR_DCD_BIT BIT(3) /* Delta CD Carrier Detect * or (IO6) * - only on 75x/76x */ -#define SC16IS7XX_MSR_CTS_BIT (1 << 4) /* CTS */ -#define SC16IS7XX_MSR_DSR_BIT (1 << 5) /* DSR (IO4) +#define SC16IS7XX_MSR_CTS_BIT BIT(4) /* CTS */ +#define SC16IS7XX_MSR_DSR_BIT BIT(5) /* DSR (IO4) * - only on 75x/76x */ -#define SC16IS7XX_MSR_RI_BIT (1 << 6) /* RI (IO7) +#define SC16IS7XX_MSR_RI_BIT BIT(6) /* RI (IO7) * - only on 75x/76x */ -#define SC16IS7XX_MSR_CD_BIT (1 << 7) /* CD (IO6) +#define SC16IS7XX_MSR_CD_BIT BIT(7) /* CD (IO6) * - only on 75x/76x */ -#define SC16IS7XX_MSR_DELTA_MASK 0x0F /* Any of the delta bits! */ /* * TCR register bits @@ -237,19 +246,19 @@ #define SC16IS7XX_TLR_RX_TRIGGER(words) ((((words) / 4) & 0x0f) << 4) /* IOControl register bits (Only 75x/76x) */ -#define SC16IS7XX_IOCONTROL_LATCH_BIT (1 << 0) /* Enable input latching */ -#define SC16IS7XX_IOCONTROL_MODEM_A_BIT (1 << 1) /* Enable GPIO[7:4] as modem A pins */ -#define SC16IS7XX_IOCONTROL_MODEM_B_BIT (1 << 2) /* Enable GPIO[3:0] as modem B pins */ -#define SC16IS7XX_IOCONTROL_SRESET_BIT (1 << 3) /* Software Reset */ +#define SC16IS7XX_IOCONTROL_LATCH_BIT BIT(0) /* Enable input latching */ +#define SC16IS7XX_IOCONTROL_MODEM_A_BIT BIT(1) /* Enable GPIO[7:4] as modem A pins */ +#define SC16IS7XX_IOCONTROL_MODEM_B_BIT BIT(2) /* Enable GPIO[3:0] as modem B pins */ +#define SC16IS7XX_IOCONTROL_SRESET_BIT BIT(3) /* Software Reset */ /* EFCR register bits */ -#define SC16IS7XX_EFCR_9BIT_MODE_BIT (1 << 0) /* Enable 9-bit or Multidrop +#define SC16IS7XX_EFCR_9BIT_MODE_BIT BIT(0) /* Enable 9-bit or Multidrop * mode (RS485) */ -#define SC16IS7XX_EFCR_RXDISABLE_BIT (1 << 1) /* Disable receiver */ -#define SC16IS7XX_EFCR_TXDISABLE_BIT (1 << 2) /* Disable transmitter */ -#define SC16IS7XX_EFCR_AUTO_RS485_BIT (1 << 4) /* Auto RS485 RTS direction */ -#define SC16IS7XX_EFCR_RTS_INVERT_BIT (1 << 5) /* RTS output inversion */ -#define SC16IS7XX_EFCR_IRDA_MODE_BIT (1 << 7) /* IrDA mode +#define SC16IS7XX_EFCR_RXDISABLE_BIT BIT(1) /* Disable receiver */ +#define SC16IS7XX_EFCR_TXDISABLE_BIT BIT(2) /* Disable transmitter */ +#define SC16IS7XX_EFCR_AUTO_RS485_BIT BIT(4) /* Auto RS485 RTS direction */ +#define SC16IS7XX_EFCR_RTS_INVERT_BIT BIT(5) /* RTS output inversion */ +#define SC16IS7XX_EFCR_IRDA_MODE_BIT BIT(7) /* IrDA mode * 0 = rate upto 115.2 kbit/s * - Only 75x/76x * 1 = rate upto 1.152 Mbit/s @@ -257,16 +266,16 @@ */ /* EFR register bits */ -#define SC16IS7XX_EFR_AUTORTS_BIT (1 << 6) /* Auto RTS flow ctrl enable */ -#define SC16IS7XX_EFR_AUTOCTS_BIT (1 << 7) /* Auto CTS flow ctrl enable */ -#define SC16IS7XX_EFR_XOFF2_DETECT_BIT (1 << 5) /* Enable Xoff2 detection */ -#define SC16IS7XX_EFR_ENABLE_BIT (1 << 4) /* Enable enhanced functions +#define SC16IS7XX_EFR_AUTORTS_BIT BIT(6) /* Auto RTS flow ctrl enable */ +#define SC16IS7XX_EFR_AUTOCTS_BIT BIT(7) /* Auto CTS flow ctrl enable */ +#define SC16IS7XX_EFR_XOFF2_DETECT_BIT BIT(5) /* Enable Xoff2 detection */ +#define SC16IS7XX_EFR_ENABLE_BIT BIT(4) /* Enable enhanced functions * and writing to IER[7:4], * FCR[5:4], MCR[7:5] */ -#define SC16IS7XX_EFR_SWFLOW3_BIT (1 << 3) /* SWFLOW bit 3 */ -#define SC16IS7XX_EFR_SWFLOW2_BIT (1 << 2) /* SWFLOW bit 2 - * +#define SC16IS7XX_EFR_SWFLOW3_BIT BIT(3) +#define SC16IS7XX_EFR_SWFLOW2_BIT BIT(2) + /* * SWFLOW bits 3 & 2 table: * 00 -> no transmitter flow * control @@ -278,10 +287,10 @@ * XON1, XON2, XOFF1 and * XOFF2 */ -#define SC16IS7XX_EFR_SWFLOW1_BIT (1 << 1) /* SWFLOW bit 2 */ -#define SC16IS7XX_EFR_SWFLOW0_BIT (1 << 0) /* SWFLOW bit 3 - * - * SWFLOW bits 3 & 2 table: +#define SC16IS7XX_EFR_SWFLOW1_BIT BIT(1) +#define SC16IS7XX_EFR_SWFLOW0_BIT BIT(0) + /* + * SWFLOW bits 1 & 0 table: * 00 -> no received flow * control * 01 -> receiver compares @@ -302,19 +311,13 @@ /* Misc definitions */ -#define SC16IS7XX_SPI_READ_BIT BIT(7) #define SC16IS7XX_FIFO_SIZE (64) #define SC16IS7XX_GPIOS_PER_BANK 4 -struct sc16is7xx_devtype { - char name[10]; - int nr_gpio; - int nr_uart; -}; - -#define SC16IS7XX_RECONF_MD (1 << 0) -#define SC16IS7XX_RECONF_IER (1 << 1) -#define SC16IS7XX_RECONF_RS485 (1 << 2) +#define SC16IS7XX_POLL_PERIOD_MS 10 +#define SC16IS7XX_RECONF_MD BIT(0) +#define SC16IS7XX_RECONF_IER BIT(1) +#define SC16IS7XX_RECONF_RS485 BIT(2) struct sc16is7xx_one_config { unsigned int flags; @@ -330,6 +333,7 @@ struct sc16is7xx_one { struct kthread_work reg_work; struct kthread_delayed_work ms_work; struct sc16is7xx_one_config config; + unsigned char buf[SC16IS7XX_FIFO_SIZE]; /* Rx buffer. */ unsigned int old_mctrl; u8 old_lcr; /* Value before EFR access. */ bool irda_mode; @@ -343,13 +347,14 @@ struct sc16is7xx_port { unsigned long gpio_valid_mask; #endif u8 mctrl_mask; - unsigned char buf[SC16IS7XX_FIFO_SIZE]; struct kthread_worker kworker; struct task_struct *kworker_task; + struct kthread_delayed_work poll_work; + bool polling; struct sc16is7xx_one p[]; }; -static DECLARE_BITMAP(sc16is7xx_lines, SC16IS7XX_MAX_DEVS); +static DEFINE_IDA(sc16is7xx_lines); static struct uart_driver sc16is7xx_uart = { .owner = THIS_MODULE, @@ -492,35 +497,40 @@ static void sc16is7xx_stop_rx(struct uart_port *port) sc16is7xx_ier_clear(port, SC16IS7XX_IER_RDI_BIT); } -static const struct sc16is7xx_devtype sc16is74x_devtype = { +const struct sc16is7xx_devtype sc16is74x_devtype = { .name = "SC16IS74X", .nr_gpio = 0, .nr_uart = 1, }; +EXPORT_SYMBOL_GPL(sc16is74x_devtype); -static const struct sc16is7xx_devtype sc16is750_devtype = { +const struct sc16is7xx_devtype sc16is750_devtype = { .name = "SC16IS750", .nr_gpio = 8, .nr_uart = 1, }; +EXPORT_SYMBOL_GPL(sc16is750_devtype); -static const struct sc16is7xx_devtype sc16is752_devtype = { +const struct sc16is7xx_devtype sc16is752_devtype = { .name = "SC16IS752", .nr_gpio = 8, .nr_uart = 2, }; +EXPORT_SYMBOL_GPL(sc16is752_devtype); -static const struct sc16is7xx_devtype sc16is760_devtype = { +const struct sc16is7xx_devtype sc16is760_devtype = { .name = "SC16IS760", .nr_gpio = 8, .nr_uart = 1, }; +EXPORT_SYMBOL_GPL(sc16is760_devtype); -static const struct sc16is7xx_devtype sc16is762_devtype = { +const struct sc16is7xx_devtype sc16is762_devtype = { .name = "SC16IS762", .nr_gpio = 8, .nr_uart = 2, }; +EXPORT_SYMBOL_GPL(sc16is762_devtype); static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg) { @@ -554,16 +564,28 @@ static bool sc16is7xx_regmap_noinc(struct device *dev, unsigned int reg) return reg == SC16IS7XX_RHR_REG; } +/* + * Configure programmable baud rate generator (divisor) according to the + * desired baud rate. + * + * From the datasheet, the divisor is computed according to: + * + * XTAL1 input frequency + * ----------------------- + * prescaler + * divisor = --------------------------- + * baud-rate x sampling-rate + */ static int sc16is7xx_set_baud(struct uart_port *port, int baud) { struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); u8 lcr; - u8 prescaler = 0; + unsigned int prescaler = 1; unsigned long clk = port->uartclk, div = clk / 16 / baud; if (div >= BIT(16)) { - prescaler = SC16IS7XX_MCR_CLKSEL_BIT; - div /= 4; + prescaler = 4; + div /= prescaler; } /* Enable enhanced features */ @@ -573,9 +595,12 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) SC16IS7XX_EFR_ENABLE_BIT); sc16is7xx_efr_unlock(port); + /* If bit MCR_CLKSEL is set, the divide by 4 prescaler is activated. */ sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, SC16IS7XX_MCR_CLKSEL_BIT, - prescaler); + prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT); + + mutex_lock(&one->efr_lock); /* Backup LCR and access special register set (DLL/DLH) */ lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG); @@ -591,24 +616,26 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) /* Restore LCR and access to general register set */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr); - return DIV_ROUND_CLOSEST(clk / 16, div); + mutex_unlock(&one->efr_lock); + + return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div); } static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, unsigned int iir) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); unsigned int lsr = 0, bytes_read, i; bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false; u8 ch, flag; - if (unlikely(rxlen >= sizeof(s->buf))) { + if (unlikely(rxlen >= sizeof(one->buf))) { dev_warn_ratelimited(port->dev, "ttySC%i: Possible RX FIFO overrun: %d\n", port->line, rxlen); port->icount.buf_overrun++; /* Ensure sanity of RX level */ - rxlen = sizeof(s->buf); + rxlen = sizeof(one->buf); } while (rxlen) { @@ -621,10 +648,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, lsr = 0; if (read_lsr) { - s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG); + one->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG); bytes_read = 1; } else { - sc16is7xx_fifo_read(port, s->buf, rxlen); + sc16is7xx_fifo_read(port, one->buf, rxlen); bytes_read = rxlen; } @@ -657,7 +684,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, } for (i = 0; i < bytes_read; ++i) { - ch = s->buf[i]; + ch = one->buf[i]; if (uart_handle_sysrq_char(port, ch)) continue; @@ -675,10 +702,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, static void sc16is7xx_handle_tx(struct uart_port *port) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); - struct circ_buf *xmit = &port->state->xmit; - unsigned int txlen, to_send, i; + struct tty_port *tport = &port->state->port; unsigned long flags; + unsigned int txlen; + unsigned char *tail; if (unlikely(port->x_char)) { sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char); @@ -687,40 +714,31 @@ static void sc16is7xx_handle_tx(struct uart_port *port) return; } - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { uart_port_lock_irqsave(port, &flags); sc16is7xx_stop_tx(port); uart_port_unlock_irqrestore(port, flags); return; } - /* Get length of data pending in circular buffer */ - to_send = uart_circ_chars_pending(xmit); - if (likely(to_send)) { - /* Limit to space available in TX FIFO */ - txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG); - if (txlen > SC16IS7XX_FIFO_SIZE) { - dev_err_ratelimited(port->dev, - "chip reports %d free bytes in TX fifo, but it only has %d", - txlen, SC16IS7XX_FIFO_SIZE); - txlen = 0; - } - to_send = (to_send > txlen) ? txlen : to_send; - - /* Convert to linear buffer */ - for (i = 0; i < to_send; ++i) { - s->buf[i] = xmit->buf[xmit->tail]; - uart_xmit_advance(port, 1); - } - - sc16is7xx_fifo_write(port, s->buf, to_send); + /* Limit to space available in TX FIFO */ + txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG); + if (txlen > SC16IS7XX_FIFO_SIZE) { + dev_err_ratelimited(port->dev, + "chip reports %d free bytes in TX fifo, but it only has %d", + txlen, SC16IS7XX_FIFO_SIZE); + txlen = 0; } + txlen = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen); + sc16is7xx_fifo_write(port, tail, txlen); + uart_xmit_advance(port, txlen); + uart_port_lock_irqsave(port, &flags); - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(port); - if (uart_circ_empty(xmit)) + if (kfifo_is_empty(&tport->xmit_fifo)) sc16is7xx_stop_tx(port); else sc16is7xx_ier_set(port, SC16IS7XX_IER_THRI_BIT); @@ -846,6 +864,18 @@ static irqreturn_t sc16is7xx_irq(int irq, void *dev_id) return IRQ_HANDLED; } +static void sc16is7xx_poll_proc(struct kthread_work *ws) +{ + struct sc16is7xx_port *s = container_of(ws, struct sc16is7xx_port, poll_work.work); + + /* Reuse standard IRQ handler. Interrupt ID is unused in this context. */ + sc16is7xx_irq(0, s); + + /* Setup delay based on SC16IS7XX_POLL_PERIOD_MS */ + kthread_queue_delayed_work(&s->kworker, &s->poll_work, + msecs_to_jiffies(SC16IS7XX_POLL_PERIOD_MS)); +} + static void sc16is7xx_tx_proc(struct kthread_work *ws) { struct uart_port *port = &(to_sc16is7xx_one(ws, tx_work)->port); @@ -1134,6 +1164,7 @@ static int sc16is7xx_config_rs485(struct uart_port *port, struct ktermios *termi static int sc16is7xx_startup(struct uart_port *port) { struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + struct sc16is7xx_port *s = dev_get_drvdata(port->dev); unsigned int val; unsigned long flags; @@ -1196,6 +1227,10 @@ static int sc16is7xx_startup(struct uart_port *port) sc16is7xx_enable_ms(port); uart_port_unlock_irqrestore(port, flags); + if (s->polling) + kthread_queue_delayed_work(&s->kworker, &s->poll_work, + msecs_to_jiffies(SC16IS7XX_POLL_PERIOD_MS)); + return 0; } @@ -1217,6 +1252,9 @@ static void sc16is7xx_shutdown(struct uart_port *port) sc16is7xx_power(port, 0); + if (s->polling) + kthread_cancel_delayed_work_sync(&s->poll_work); + kthread_flush_worker(&s->kworker); } @@ -1458,20 +1496,43 @@ static int sc16is7xx_setup_mctrl_ports(struct sc16is7xx_port *s, } static const struct serial_rs485 sc16is7xx_rs485_supported = { - .flags = SER_RS485_ENABLED | SER_RS485_RTS_AFTER_SEND, + .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND, .delay_rts_before_send = 1, .delay_rts_after_send = 1, /* Not supported but keep returning -EINVAL */ }; -static int sc16is7xx_probe(struct device *dev, - const struct sc16is7xx_devtype *devtype, - struct regmap *regmaps[], int irq) +/* Reset device, purging any pending irq / data */ +static int sc16is7xx_reset(struct device *dev, struct regmap *regmap) +{ + struct gpio_desc *reset_gpio; + + /* Assert reset GPIO if defined and valid. */ + reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(reset_gpio)) + return dev_err_probe(dev, PTR_ERR(reset_gpio), "Failed to get reset GPIO\n"); + + if (reset_gpio) { + /* The minimum reset pulse width is 3 us. */ + fsleep(5); + gpiod_set_value_cansleep(reset_gpio, 0); /* Deassert GPIO */ + } else { + /* Software reset */ + regmap_write(regmap, SC16IS7XX_IOCONTROL_REG, + SC16IS7XX_IOCONTROL_SRESET_BIT); + } + + return 0; +} + +int sc16is7xx_probe(struct device *dev, const struct sc16is7xx_devtype *devtype, + struct regmap *regmaps[], int irq) { unsigned long freq = 0, *pfreq = dev_get_platdata(dev); unsigned int val; u32 uartclk = 0; int i, ret; struct sc16is7xx_port *s; + bool port_registered[SC16IS7XX_MAX_PORTS]; for (i = 0; i < devtype->nr_uart; i++) if (IS_ERR(regmaps[i])) @@ -1500,6 +1561,11 @@ static int sc16is7xx_probe(struct device *dev, /* Always ask for fixed clock rate from a property. */ device_property_read_u32(dev, "clock-frequency", &uartclk); + s->polling = !!irq; + if (s->polling) + dev_dbg(dev, + "No interrupt pin definition, falling back to polling mode\n"); + s->clk = devm_clk_get_optional(dev, NULL); if (IS_ERR(s->clk)) return PTR_ERR(s->clk); @@ -1532,17 +1598,23 @@ static int sc16is7xx_probe(struct device *dev, } sched_set_fifo(s->kworker_task); - /* reset device, purging any pending irq / data */ - regmap_write(regmaps[0], SC16IS7XX_IOCONTROL_REG, - SC16IS7XX_IOCONTROL_SRESET_BIT); + ret = sc16is7xx_reset(dev, regmaps[0]); + if (ret) + goto out_kthread; + + /* Mark each port line and status as uninitialised. */ + for (i = 0; i < devtype->nr_uart; ++i) { + s->p[i].port.line = SC16IS7XX_MAX_DEVS; + port_registered[i] = false; + } for (i = 0; i < devtype->nr_uart; ++i) { - s->p[i].port.line = find_first_zero_bit(sc16is7xx_lines, - SC16IS7XX_MAX_DEVS); - if (s->p[i].port.line >= SC16IS7XX_MAX_DEVS) { - ret = -ERANGE; + ret = ida_alloc_max(&sc16is7xx_lines, + SC16IS7XX_MAX_DEVS - 1, GFP_KERNEL); + if (ret < 0) goto out_ports; - } + + s->p[i].port.line = ret; /* Initialize port data */ s->p[i].port.dev = dev; @@ -1588,7 +1660,7 @@ static int sc16is7xx_probe(struct device *dev, if (ret) goto out_ports; - set_bit(s->p[i].port.line, sc16is7xx_lines); + port_registered[i] = true; /* Enable EFR */ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_LCR_REG, @@ -1621,6 +1693,12 @@ static int sc16is7xx_probe(struct device *dev, goto out_ports; #endif + if (s->polling) { + /* Initialize kernel thread for polling */ + kthread_init_delayed_work(&s->poll_work, sc16is7xx_poll_proc); + return 0; + } + /* * Setup interrupt. We first try to acquire the IRQ line as level IRQ. * If that succeeds, we can allow sharing the interrupt as well. @@ -1646,10 +1724,14 @@ static int sc16is7xx_probe(struct device *dev, #endif out_ports: - for (i = 0; i < devtype->nr_uart; i++) - if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines)) + for (i = 0; i < devtype->nr_uart; i++) { + if (s->p[i].port.line < SC16IS7XX_MAX_DEVS) + ida_free(&sc16is7xx_lines, s->p[i].port.line); + if (port_registered[i]) uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port); + } +out_kthread: kthread_stop(s->kworker_task); out_clk: @@ -1657,8 +1739,9 @@ out_clk: return ret; } +EXPORT_SYMBOL_GPL(sc16is7xx_probe); -static void sc16is7xx_remove(struct device *dev) +void sc16is7xx_remove(struct device *dev) { struct sc16is7xx_port *s = dev_get_drvdata(dev); int i; @@ -1670,18 +1753,22 @@ static void sc16is7xx_remove(struct device *dev) for (i = 0; i < s->devtype->nr_uart; i++) { kthread_cancel_delayed_work_sync(&s->p[i].ms_work); - if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines)) - uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port); + ida_free(&sc16is7xx_lines, s->p[i].port.line); + uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port); sc16is7xx_power(&s->p[i].port, 0); } + if (s->polling) + kthread_cancel_delayed_work_sync(&s->poll_work); + kthread_flush_worker(&s->kworker); kthread_stop(s->kworker_task); clk_disable_unprepare(s->clk); } +EXPORT_SYMBOL_GPL(sc16is7xx_remove); -static const struct of_device_id __maybe_unused sc16is7xx_dt_ids[] = { +const struct of_device_id __maybe_unused sc16is7xx_dt_ids[] = { { .compatible = "nxp,sc16is740", .data = &sc16is74x_devtype, }, { .compatible = "nxp,sc16is741", .data = &sc16is74x_devtype, }, { .compatible = "nxp,sc16is750", .data = &sc16is750_devtype, }, @@ -1690,13 +1777,14 @@ static const struct of_device_id __maybe_unused sc16is7xx_dt_ids[] = { { .compatible = "nxp,sc16is762", .data = &sc16is762_devtype, }, { } }; +EXPORT_SYMBOL_GPL(sc16is7xx_dt_ids); MODULE_DEVICE_TABLE(of, sc16is7xx_dt_ids); -static struct regmap_config regcfg = { +const struct regmap_config sc16is7xx_regcfg = { .reg_bits = 5, .pad_bits = 3, .val_bits = 8, - .cache_type = REGCACHE_RBTREE, + .cache_type = REGCACHE_MAPLE, .volatile_reg = sc16is7xx_regmap_volatile, .precious_reg = sc16is7xx_regmap_precious, .writeable_noinc_reg = sc16is7xx_regmap_noinc, @@ -1705,8 +1793,9 @@ static struct regmap_config regcfg = { .max_raw_write = SC16IS7XX_FIFO_SIZE, .max_register = SC16IS7XX_EFCR_REG, }; +EXPORT_SYMBOL_GPL(sc16is7xx_regcfg); -static const char *sc16is7xx_regmap_name(u8 port_id) +const char *sc16is7xx_regmap_name(u8 port_id) { switch (port_id) { case 0: return "port0"; @@ -1716,184 +1805,27 @@ static const char *sc16is7xx_regmap_name(u8 port_id) return NULL; } } +EXPORT_SYMBOL_GPL(sc16is7xx_regmap_name); -static unsigned int sc16is7xx_regmap_port_mask(unsigned int port_id) +unsigned int sc16is7xx_regmap_port_mask(unsigned int port_id) { /* CH1,CH0 are at bits 2:1. */ return port_id << 1; } - -#ifdef CONFIG_SERIAL_SC16IS7XX_SPI -static int sc16is7xx_spi_probe(struct spi_device *spi) -{ - const struct sc16is7xx_devtype *devtype; - struct regmap *regmaps[SC16IS7XX_MAX_PORTS]; - unsigned int i; - int ret; - - /* Setup SPI bus */ - spi->bits_per_word = 8; - /* For all variants, only mode 0 is supported */ - if ((spi->mode & SPI_MODE_X_MASK) != SPI_MODE_0) - return dev_err_probe(&spi->dev, -EINVAL, "Unsupported SPI mode\n"); - - spi->mode = spi->mode ? : SPI_MODE_0; - spi->max_speed_hz = spi->max_speed_hz ? : 4 * HZ_PER_MHZ; - ret = spi_setup(spi); - if (ret) - return ret; - - devtype = spi_get_device_match_data(spi); - if (!devtype) - return dev_err_probe(&spi->dev, -ENODEV, "Failed to match device\n"); - - for (i = 0; i < devtype->nr_uart; i++) { - regcfg.name = sc16is7xx_regmap_name(i); - /* - * If read_flag_mask is 0, the regmap code sets it to a default - * of 0x80. Since we specify our own mask, we must add the READ - * bit ourselves: - */ - regcfg.read_flag_mask = sc16is7xx_regmap_port_mask(i) | - SC16IS7XX_SPI_READ_BIT; - regcfg.write_flag_mask = sc16is7xx_regmap_port_mask(i); - regmaps[i] = devm_regmap_init_spi(spi, ®cfg); - } - - return sc16is7xx_probe(&spi->dev, devtype, regmaps, spi->irq); -} - -static void sc16is7xx_spi_remove(struct spi_device *spi) -{ - sc16is7xx_remove(&spi->dev); -} - -static const struct spi_device_id sc16is7xx_spi_id_table[] = { - { "sc16is74x", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is740", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is741", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is750", (kernel_ulong_t)&sc16is750_devtype, }, - { "sc16is752", (kernel_ulong_t)&sc16is752_devtype, }, - { "sc16is760", (kernel_ulong_t)&sc16is760_devtype, }, - { "sc16is762", (kernel_ulong_t)&sc16is762_devtype, }, - { } -}; - -MODULE_DEVICE_TABLE(spi, sc16is7xx_spi_id_table); - -static struct spi_driver sc16is7xx_spi_uart_driver = { - .driver = { - .name = SC16IS7XX_NAME, - .of_match_table = sc16is7xx_dt_ids, - }, - .probe = sc16is7xx_spi_probe, - .remove = sc16is7xx_spi_remove, - .id_table = sc16is7xx_spi_id_table, -}; -#endif - -#ifdef CONFIG_SERIAL_SC16IS7XX_I2C -static int sc16is7xx_i2c_probe(struct i2c_client *i2c) -{ - const struct sc16is7xx_devtype *devtype; - struct regmap *regmaps[SC16IS7XX_MAX_PORTS]; - unsigned int i; - - devtype = i2c_get_match_data(i2c); - if (!devtype) - return dev_err_probe(&i2c->dev, -ENODEV, "Failed to match device\n"); - - for (i = 0; i < devtype->nr_uart; i++) { - regcfg.name = sc16is7xx_regmap_name(i); - regcfg.read_flag_mask = sc16is7xx_regmap_port_mask(i); - regcfg.write_flag_mask = sc16is7xx_regmap_port_mask(i); - regmaps[i] = devm_regmap_init_i2c(i2c, ®cfg); - } - - return sc16is7xx_probe(&i2c->dev, devtype, regmaps, i2c->irq); -} - -static void sc16is7xx_i2c_remove(struct i2c_client *client) -{ - sc16is7xx_remove(&client->dev); -} - -static const struct i2c_device_id sc16is7xx_i2c_id_table[] = { - { "sc16is74x", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is740", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is741", (kernel_ulong_t)&sc16is74x_devtype, }, - { "sc16is750", (kernel_ulong_t)&sc16is750_devtype, }, - { "sc16is752", (kernel_ulong_t)&sc16is752_devtype, }, - { "sc16is760", (kernel_ulong_t)&sc16is760_devtype, }, - { "sc16is762", (kernel_ulong_t)&sc16is762_devtype, }, - { } -}; -MODULE_DEVICE_TABLE(i2c, sc16is7xx_i2c_id_table); - -static struct i2c_driver sc16is7xx_i2c_uart_driver = { - .driver = { - .name = SC16IS7XX_NAME, - .of_match_table = sc16is7xx_dt_ids, - }, - .probe = sc16is7xx_i2c_probe, - .remove = sc16is7xx_i2c_remove, - .id_table = sc16is7xx_i2c_id_table, -}; - -#endif +EXPORT_SYMBOL_GPL(sc16is7xx_regmap_port_mask); static int __init sc16is7xx_init(void) { - int ret; - - ret = uart_register_driver(&sc16is7xx_uart); - if (ret) { - pr_err("Registering UART driver failed\n"); - return ret; - } - -#ifdef CONFIG_SERIAL_SC16IS7XX_I2C - ret = i2c_add_driver(&sc16is7xx_i2c_uart_driver); - if (ret < 0) { - pr_err("failed to init sc16is7xx i2c --> %d\n", ret); - goto err_i2c; - } -#endif - -#ifdef CONFIG_SERIAL_SC16IS7XX_SPI - ret = spi_register_driver(&sc16is7xx_spi_uart_driver); - if (ret < 0) { - pr_err("failed to init sc16is7xx spi --> %d\n", ret); - goto err_spi; - } -#endif - return ret; - -#ifdef CONFIG_SERIAL_SC16IS7XX_SPI -err_spi: -#endif -#ifdef CONFIG_SERIAL_SC16IS7XX_I2C - i2c_del_driver(&sc16is7xx_i2c_uart_driver); -err_i2c: -#endif - uart_unregister_driver(&sc16is7xx_uart); - return ret; + return uart_register_driver(&sc16is7xx_uart); } module_init(sc16is7xx_init); static void __exit sc16is7xx_exit(void) { -#ifdef CONFIG_SERIAL_SC16IS7XX_I2C - i2c_del_driver(&sc16is7xx_i2c_uart_driver); -#endif - -#ifdef CONFIG_SERIAL_SC16IS7XX_SPI - spi_unregister_driver(&sc16is7xx_spi_uart_driver); -#endif uart_unregister_driver(&sc16is7xx_uart); } module_exit(sc16is7xx_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>"); -MODULE_DESCRIPTION("SC16IS7XX serial driver"); +MODULE_DESCRIPTION("SC16IS7xx tty serial core driver"); |