diff options
Diffstat (limited to 'drivers/tty/serial/sc16is7xx.c')
-rw-r--r-- | drivers/tty/serial/sc16is7xx.c | 322 |
1 files changed, 87 insertions, 235 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index ace2c4b333..9547aa8f45 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -1,19 +1,22 @@ // 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/clk.h> #include <linux/delay.h> #include <linux/device.h> +#include <linux/export.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> @@ -21,15 +24,15 @@ #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> -#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 */ @@ -302,16 +305,9 @@ /* 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) @@ -330,6 +326,7 @@ 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 +340,12 @@ 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 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 +488,40 @@ 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) { @@ -590,6 +591,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) SC16IS7XX_MCR_CLKSEL_BIT, 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); sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, @@ -604,24 +607,26 @@ 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); + 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) { @@ -634,10 +639,10 @@ 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; } @@ -670,7 +675,7 @@ 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; @@ -688,10 +693,10 @@ 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); @@ -700,40 +705,31 @@ 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); @@ -1476,15 +1472,15 @@ static const struct serial_rs485 sc16is7xx_rs485_supported = { .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) +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])) @@ -1549,13 +1545,19 @@ static int sc16is7xx_probe(struct device *dev, regmap_write(regmaps[0], SC16IS7XX_IOCONTROL_REG, SC16IS7XX_IOCONTROL_SRESET_BIT); + /* Mark each port line and status as uninitialised. */ 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; + s->p[i].port.line = SC16IS7XX_MAX_DEVS; + port_registered[i] = false; + } + + for (i = 0; i < devtype->nr_uart; ++i) { + 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; @@ -1601,7 +1603,7 @@ 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, @@ -1659,9 +1661,12 @@ 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); + } kthread_stop(s->kworker_task); @@ -1670,8 +1675,9 @@ 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; @@ -1683,8 +1689,8 @@ 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); } @@ -1693,8 +1699,9 @@ static void sc16is7xx_remove(struct device *dev) 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, }, @@ -1703,13 +1710,14 @@ 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, @@ -1718,8 +1726,9 @@ 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"; @@ -1729,184 +1738,27 @@ 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"); |