From 50ba0232fd5312410f1b65247e774244f89a628e Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 20:50:36 +0200 Subject: Merging upstream version 6.8.9. Signed-off-by: Daniel Baumann --- drivers/tty/serial/sc16is7xx.c | 252 ++++++++++++++++++++--------------------- 1 file changed, 120 insertions(+), 132 deletions(-) (limited to 'drivers/tty/serial/sc16is7xx.c') diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index dba25e7090..929206a9a6 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -29,6 +29,7 @@ #define SC16IS7XX_NAME "sc16is7xx" #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 */ @@ -329,8 +330,9 @@ struct sc16is7xx_one { struct kthread_work reg_work; struct kthread_delayed_work ms_work; struct sc16is7xx_one_config config; - bool irda_mode; unsigned int old_mctrl; + u8 old_lcr; /* Value before EFR access. */ + bool irda_mode; }; struct sc16is7xx_port { @@ -347,17 +349,15 @@ struct sc16is7xx_port { struct sc16is7xx_one p[]; }; -static unsigned long sc16is7xx_lines; +static DECLARE_BITMAP(sc16is7xx_lines, SC16IS7XX_MAX_DEVS); static struct uart_driver sc16is7xx_uart = { .owner = THIS_MODULE, + .driver_name = SC16IS7XX_NAME, .dev_name = "ttySC", .nr = SC16IS7XX_MAX_DEVS, }; -static void sc16is7xx_ier_set(struct uart_port *port, u8 bit); -static void sc16is7xx_stop_tx(struct uart_port *port); - #define to_sc16is7xx_one(p,e) ((container_of((p), struct sc16is7xx_one, e))) static u8 sc16is7xx_port_read(struct uart_port *port, u8 reg) @@ -377,17 +377,15 @@ static void sc16is7xx_port_write(struct uart_port *port, u8 reg, u8 val) regmap_write(one->regmap, reg, val); } -static void sc16is7xx_fifo_read(struct uart_port *port, unsigned int rxlen) +static void sc16is7xx_fifo_read(struct uart_port *port, u8 *rxbuf, unsigned int rxlen) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); - regmap_noinc_read(one->regmap, SC16IS7XX_RHR_REG, s->buf, rxlen); + regmap_noinc_read(one->regmap, SC16IS7XX_RHR_REG, rxbuf, rxlen); } -static void sc16is7xx_fifo_write(struct uart_port *port, u8 to_send) +static void sc16is7xx_fifo_write(struct uart_port *port, u8 *txbuf, u8 to_send) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); /* @@ -397,7 +395,7 @@ static void sc16is7xx_fifo_write(struct uart_port *port, u8 to_send) if (unlikely(!to_send)) return; - regmap_noinc_write(one->regmap, SC16IS7XX_THR_REG, s->buf, to_send); + regmap_noinc_write(one->regmap, SC16IS7XX_THR_REG, txbuf, to_send); } static void sc16is7xx_port_update(struct uart_port *port, u8 reg, @@ -415,6 +413,85 @@ static void sc16is7xx_power(struct uart_port *port, int on) on ? 0 : SC16IS7XX_IER_SLEEP_BIT); } +/* + * In an amazing feat of design, the Enhanced Features Register (EFR) + * shares the address of the Interrupt Identification Register (IIR). + * Access to EFR is switched on by writing a magic value (0xbf) to the + * Line Control Register (LCR). Any interrupt firing during this time will + * see the EFR where it expects the IIR to be, leading to + * "Unexpected interrupt" messages. + * + * Prevent this possibility by claiming a mutex while accessing the EFR, + * and claiming the same mutex from within the interrupt handler. This is + * similar to disabling the interrupt, but that doesn't work because the + * bulk of the interrupt processing is run as a workqueue job in thread + * context. + */ +static void sc16is7xx_efr_lock(struct uart_port *port) +{ + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + + mutex_lock(&one->efr_lock); + + /* Backup content of LCR. */ + one->old_lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG); + + /* Enable access to Enhanced register set */ + sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_CONF_MODE_B); + + /* Disable cache updates when writing to EFR registers */ + regcache_cache_bypass(one->regmap, true); +} + +static void sc16is7xx_efr_unlock(struct uart_port *port) +{ + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + + /* Re-enable cache updates when writing to normal registers */ + regcache_cache_bypass(one->regmap, false); + + /* Restore original content of LCR */ + sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, one->old_lcr); + + mutex_unlock(&one->efr_lock); +} + +static void sc16is7xx_ier_clear(struct uart_port *port, u8 bit) +{ + struct sc16is7xx_port *s = dev_get_drvdata(port->dev); + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + + lockdep_assert_held_once(&port->lock); + + one->config.flags |= SC16IS7XX_RECONF_IER; + one->config.ier_mask |= bit; + one->config.ier_val &= ~bit; + kthread_queue_work(&s->kworker, &one->reg_work); +} + +static void sc16is7xx_ier_set(struct uart_port *port, u8 bit) +{ + struct sc16is7xx_port *s = dev_get_drvdata(port->dev); + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + + lockdep_assert_held_once(&port->lock); + + one->config.flags |= SC16IS7XX_RECONF_IER; + one->config.ier_mask |= bit; + one->config.ier_val |= bit; + kthread_queue_work(&s->kworker, &one->reg_work); +} + +static void sc16is7xx_stop_tx(struct uart_port *port) +{ + sc16is7xx_ier_clear(port, SC16IS7XX_IER_THRI_BIT); +} + +static void sc16is7xx_stop_rx(struct uart_port *port) +{ + sc16is7xx_ier_clear(port, SC16IS7XX_IER_RDI_BIT); +} + static const struct sc16is7xx_devtype sc16is74x_devtype = { .name = "SC16IS74X", .nr_gpio = 0, @@ -458,10 +535,8 @@ static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg) case SC16IS7XX_IOCONTROL_REG: return true; default: - break; + return false; } - - return false; } static bool sc16is7xx_regmap_precious(struct device *dev, unsigned int reg) @@ -470,10 +545,8 @@ static bool sc16is7xx_regmap_precious(struct device *dev, unsigned int reg) case SC16IS7XX_RHR_REG: return true; default: - break; + return false; } - - return false; } static bool sc16is7xx_regmap_noinc(struct device *dev, unsigned int reg) @@ -488,50 +561,24 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) u8 prescaler = 0; unsigned long clk = port->uartclk, div = clk / 16 / baud; - if (div > 0xffff) { + if (div >= BIT(16)) { prescaler = SC16IS7XX_MCR_CLKSEL_BIT; div /= 4; } - /* In an amazing feat of design, the Enhanced Features Register shares - * the address of the Interrupt Identification Register, and is - * switched in by writing a magic value (0xbf) to the Line Control - * Register. Any interrupt firing during this time will see the EFR - * where it expects the IIR to be, leading to "Unexpected interrupt" - * messages. - * - * Prevent this possibility by claiming a mutex while accessing the - * EFR, and claiming the same mutex from within the interrupt handler. - * This is similar to disabling the interrupt, but that doesn't work - * because the bulk of the interrupt processing is run as a workqueue - * job in thread context. - */ - mutex_lock(&one->efr_lock); - - lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG); - - /* Open the LCR divisors for configuration */ - sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, - SC16IS7XX_LCR_CONF_MODE_B); - /* Enable enhanced features */ - regcache_cache_bypass(one->regmap, true); + sc16is7xx_efr_lock(port); sc16is7xx_port_update(port, SC16IS7XX_EFR_REG, SC16IS7XX_EFR_ENABLE_BIT, SC16IS7XX_EFR_ENABLE_BIT); - - regcache_cache_bypass(one->regmap, false); - - /* Put LCR back to the normal mode */ - sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr); - - mutex_unlock(&one->efr_lock); + sc16is7xx_efr_unlock(port); sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, SC16IS7XX_MCR_CLKSEL_BIT, prescaler); - /* Open the LCR divisors for configuration */ + /* Backup LCR and access special register set (DLL/DLH) */ + lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG); sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_CONF_MODE_A); @@ -541,7 +588,7 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) sc16is7xx_port_write(port, SC16IS7XX_DLL_REG, div % 256); regcache_cache_bypass(one->regmap, false); - /* Put LCR back to the normal mode */ + /* Restore LCR and access to general register set */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr); return DIV_ROUND_CLOSEST(clk / 16, div); @@ -577,7 +624,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG); bytes_read = 1; } else { - sc16is7xx_fifo_read(port, rxlen); + sc16is7xx_fifo_read(port, s->buf, rxlen); bytes_read = rxlen; } @@ -650,7 +697,7 @@ static void sc16is7xx_handle_tx(struct uart_port *port) /* Get length of data pending in circular buffer */ to_send = uart_circ_chars_pending(xmit); if (likely(to_send)) { - /* Limit to size of TX FIFO */ + /* 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, @@ -666,7 +713,7 @@ static void sc16is7xx_handle_tx(struct uart_port *port) uart_xmit_advance(port, 1); } - sc16is7xx_fifo_write(port, to_send); + sc16is7xx_fifo_write(port, s->buf, to_send); } uart_port_lock_irqsave(port, &flags); @@ -871,42 +918,6 @@ static void sc16is7xx_reg_proc(struct kthread_work *ws) sc16is7xx_reconf_rs485(&one->port); } -static void sc16is7xx_ier_clear(struct uart_port *port, u8 bit) -{ - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); - struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); - - lockdep_assert_held_once(&port->lock); - - one->config.flags |= SC16IS7XX_RECONF_IER; - one->config.ier_mask |= bit; - one->config.ier_val &= ~bit; - kthread_queue_work(&s->kworker, &one->reg_work); -} - -static void sc16is7xx_ier_set(struct uart_port *port, u8 bit) -{ - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); - struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); - - lockdep_assert_held_once(&port->lock); - - one->config.flags |= SC16IS7XX_RECONF_IER; - one->config.ier_mask |= bit; - one->config.ier_val |= bit; - kthread_queue_work(&s->kworker, &one->reg_work); -} - -static void sc16is7xx_stop_tx(struct uart_port *port) -{ - sc16is7xx_ier_clear(port, SC16IS7XX_IER_THRI_BIT); -} - -static void sc16is7xx_stop_rx(struct uart_port *port) -{ - sc16is7xx_ier_clear(port, SC16IS7XX_IER_RDI_BIT); -} - static void sc16is7xx_ms_proc(struct kthread_work *ws) { struct sc16is7xx_one *one = to_sc16is7xx_one(ws, ms_work.work); @@ -1056,17 +1067,7 @@ static void sc16is7xx_set_termios(struct uart_port *port, if (!(termios->c_cflag & CREAD)) port->ignore_status_mask |= SC16IS7XX_LSR_BRK_ERROR_MASK; - /* As above, claim the mutex while accessing the EFR. */ - mutex_lock(&one->efr_lock); - - sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, - SC16IS7XX_LCR_CONF_MODE_B); - /* Configure flow control */ - regcache_cache_bypass(one->regmap, true); - sc16is7xx_port_write(port, SC16IS7XX_XON1_REG, termios->c_cc[VSTART]); - sc16is7xx_port_write(port, SC16IS7XX_XOFF1_REG, termios->c_cc[VSTOP]); - port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS); if (termios->c_cflag & CRTSCTS) { flow |= SC16IS7XX_EFR_AUTOCTS_BIT | @@ -1078,16 +1079,16 @@ static void sc16is7xx_set_termios(struct uart_port *port, if (termios->c_iflag & IXOFF) flow |= SC16IS7XX_EFR_SWFLOW1_BIT; - sc16is7xx_port_update(port, - SC16IS7XX_EFR_REG, - SC16IS7XX_EFR_FLOWCTRL_BITS, - flow); - regcache_cache_bypass(one->regmap, false); - /* Update LCR register */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr); - mutex_unlock(&one->efr_lock); + /* Update EFR registers */ + sc16is7xx_efr_lock(port); + sc16is7xx_port_write(port, SC16IS7XX_XON1_REG, termios->c_cc[VSTART]); + sc16is7xx_port_write(port, SC16IS7XX_XOFF1_REG, termios->c_cc[VSTOP]); + sc16is7xx_port_update(port, SC16IS7XX_EFR_REG, + SC16IS7XX_EFR_FLOWCTRL_BITS, flow); + sc16is7xx_efr_unlock(port); /* Get baud rate generator configuration */ baud = uart_get_baud_rate(port, termios, old, @@ -1397,7 +1398,7 @@ static void sc16is7xx_setup_irda_ports(struct sc16is7xx_port *s) int i; int ret; int count; - u32 irda_port[2]; + u32 irda_port[SC16IS7XX_MAX_PORTS]; struct device *dev = s->p[0].port.dev; count = device_property_count_u32(dev, "irda-mode-ports"); @@ -1424,7 +1425,7 @@ static int sc16is7xx_setup_mctrl_ports(struct sc16is7xx_port *s, int i; int ret; int count; - u32 mctrl_port[2]; + u32 mctrl_port[SC16IS7XX_MAX_PORTS]; struct device *dev = s->p[0].port.dev; count = device_property_count_u32(dev, "nxp,modem-control-line-ports"); @@ -1536,7 +1537,7 @@ static int sc16is7xx_probe(struct device *dev, SC16IS7XX_IOCONTROL_SRESET_BIT); for (i = 0; i < devtype->nr_uart; ++i) { - s->p[i].port.line = find_first_zero_bit(&sc16is7xx_lines, + 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; @@ -1587,7 +1588,7 @@ static int sc16is7xx_probe(struct device *dev, if (ret) goto out_ports; - set_bit(s->p[i].port.line, &sc16is7xx_lines); + set_bit(s->p[i].port.line, sc16is7xx_lines); /* Enable EFR */ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_LCR_REG, @@ -1646,7 +1647,7 @@ static int sc16is7xx_probe(struct device *dev, out_ports: for (i = 0; i < devtype->nr_uart; i++) - if (test_and_clear_bit(s->p[i].port.line, &sc16is7xx_lines)) + if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines)) uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port); kthread_stop(s->kworker_task); @@ -1669,7 +1670,7 @@ 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)) + if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines)) uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port); sc16is7xx_power(&s->p[i].port, 0); } @@ -1726,7 +1727,7 @@ static unsigned int sc16is7xx_regmap_port_mask(unsigned int port_id) static int sc16is7xx_spi_probe(struct spi_device *spi) { const struct sc16is7xx_devtype *devtype; - struct regmap *regmaps[2]; + struct regmap *regmaps[SC16IS7XX_MAX_PORTS]; unsigned int i; int ret; @@ -1742,15 +1743,9 @@ static int sc16is7xx_spi_probe(struct spi_device *spi) if (ret) return ret; - if (spi->dev.of_node) { - devtype = device_get_match_data(&spi->dev); - if (!devtype) - return -ENODEV; - } else { - const struct spi_device_id *id_entry = spi_get_device_id(spi); - - devtype = (struct sc16is7xx_devtype *)id_entry->driver_data; - } + 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); @@ -1795,25 +1790,18 @@ static struct spi_driver sc16is7xx_spi_uart_driver = { .remove = sc16is7xx_spi_remove, .id_table = sc16is7xx_spi_id_table, }; - -MODULE_ALIAS("spi:sc16is7xx"); #endif #ifdef CONFIG_SERIAL_SC16IS7XX_I2C static int sc16is7xx_i2c_probe(struct i2c_client *i2c) { - const struct i2c_device_id *id = i2c_client_get_device_id(i2c); const struct sc16is7xx_devtype *devtype; - struct regmap *regmaps[2]; + struct regmap *regmaps[SC16IS7XX_MAX_PORTS]; unsigned int i; - if (i2c->dev.of_node) { - devtype = device_get_match_data(&i2c->dev); - if (!devtype) - return -ENODEV; - } else { - devtype = (struct sc16is7xx_devtype *)id->driver_data; - } + 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); -- cgit v1.2.3