diff options
Diffstat (limited to 'drivers/tty/serial/atmel_serial.c')
-rw-r--r-- | drivers/tty/serial/atmel_serial.c | 180 |
1 files changed, 111 insertions, 69 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 1c0884d8ef32..d9439e6ab719 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -159,8 +159,9 @@ struct atmel_uart_port { u32 rts_high; u32 rts_low; bool ms_irq_enabled; - bool is_usart; /* usart or uart */ - struct timer_list uart_timer; /* uart timer */ + u32 rtor; /* address of receiver timeout register if it exists */ + bool has_hw_timer; + struct timer_list uart_timer; bool suspended; unsigned int pending; @@ -1710,19 +1711,24 @@ static void atmel_get_ip_name(struct uart_port *port) struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); int name = atmel_uart_readl(port, ATMEL_US_NAME); u32 version; - int usart, uart; - /* usart and uart ascii */ - usart = 0x55534152; - uart = 0x44424755; - - atmel_port->is_usart = false; - - if (name == usart) { - dev_dbg(port->dev, "This is usart\n"); - atmel_port->is_usart = true; - } else if (name == uart) { - dev_dbg(port->dev, "This is uart\n"); - atmel_port->is_usart = false; + u32 usart, dbgu_uart, new_uart; + /* ASCII decoding for IP version */ + usart = 0x55534152; /* USAR(T) */ + dbgu_uart = 0x44424755; /* DBGU */ + new_uart = 0x55415254; /* UART */ + + atmel_port->has_hw_timer = false; + + if (name == new_uart) { + dev_dbg(port->dev, "Uart with hw timer"); + atmel_port->has_hw_timer = true; + atmel_port->rtor = ATMEL_UA_RTOR; + } else if (name == usart) { + dev_dbg(port->dev, "Usart\n"); + atmel_port->has_hw_timer = true; + atmel_port->rtor = ATMEL_US_RTOR; + } else if (name == dbgu_uart) { + dev_dbg(port->dev, "Dbgu or uart without hw timer\n"); } else { /* fallback for older SoCs: use version field */ version = atmel_uart_readl(port, ATMEL_US_VERSION); @@ -1730,12 +1736,12 @@ static void atmel_get_ip_name(struct uart_port *port) case 0x302: case 0x10213: dev_dbg(port->dev, "This version is usart\n"); - atmel_port->is_usart = true; + atmel_port->has_hw_timer = true; + atmel_port->rtor = ATMEL_US_RTOR; break; case 0x203: case 0x10202: dev_dbg(port->dev, "This version is uart\n"); - atmel_port->is_usart = false; break; default: dev_err(port->dev, "Not supported ip name nor version, set to uart\n"); @@ -1835,12 +1841,13 @@ static int atmel_startup(struct uart_port *port) if (atmel_use_pdc_rx(port)) { /* set UART timeout */ - if (!atmel_port->is_usart) { + if (!atmel_port->has_hw_timer) { mod_timer(&atmel_port->uart_timer, jiffies + uart_poll_timeout(port)); /* set USART timeout */ } else { - atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT); + atmel_uart_writel(port, atmel_port->rtor, + PDC_RX_TIMEOUT); atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO); atmel_uart_writel(port, ATMEL_US_IER, @@ -1850,12 +1857,13 @@ static int atmel_startup(struct uart_port *port) atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN); } else if (atmel_use_dma_rx(port)) { /* set UART timeout */ - if (!atmel_port->is_usart) { + if (!atmel_port->has_hw_timer) { mod_timer(&atmel_port->uart_timer, jiffies + uart_poll_timeout(port)); /* set USART timeout */ } else { - atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT); + atmel_uart_writel(port, atmel_port->rtor, + PDC_RX_TIMEOUT); atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO); atmel_uart_writel(port, ATMEL_US_IER, @@ -2478,13 +2486,13 @@ static int __init atmel_console_init(void) struct atmel_uart_data *pdata = dev_get_platdata(&atmel_default_console_device->dev); int id = pdata->num; - struct atmel_uart_port *port = &atmel_ports[id]; + struct atmel_uart_port *atmel_port = &atmel_ports[id]; - port->backup_imr = 0; - port->uart.line = id; + atmel_port->backup_imr = 0; + atmel_port->uart.line = id; add_preferred_console(ATMEL_DEVICENAME, id, NULL); - ret = atmel_init_port(port, atmel_default_console_device); + ret = atmel_init_port(atmel_port, atmel_default_console_device); if (ret) return ret; register_console(&atmel_console); @@ -2599,23 +2607,23 @@ static int atmel_serial_resume(struct platform_device *pdev) #define atmel_serial_resume NULL #endif -static void atmel_serial_probe_fifos(struct atmel_uart_port *port, +static void atmel_serial_probe_fifos(struct atmel_uart_port *atmel_port, struct platform_device *pdev) { - port->fifo_size = 0; - port->rts_low = 0; - port->rts_high = 0; + atmel_port->fifo_size = 0; + atmel_port->rts_low = 0; + atmel_port->rts_high = 0; if (of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size", - &port->fifo_size)) + &atmel_port->fifo_size)) return; - if (!port->fifo_size) + if (!atmel_port->fifo_size) return; - if (port->fifo_size < ATMEL_MIN_FIFO_SIZE) { - port->fifo_size = 0; + if (atmel_port->fifo_size < ATMEL_MIN_FIFO_SIZE) { + atmel_port->fifo_size = 0; dev_err(&pdev->dev, "Invalid FIFO size\n"); return; } @@ -2628,22 +2636,22 @@ static void atmel_serial_probe_fifos(struct atmel_uart_port *port, * Threshold to a reasonably high value respecting this 16 data * empirical rule when possible. */ - port->rts_high = max_t(int, port->fifo_size >> 1, - port->fifo_size - ATMEL_RTS_HIGH_OFFSET); - port->rts_low = max_t(int, port->fifo_size >> 2, - port->fifo_size - ATMEL_RTS_LOW_OFFSET); + atmel_port->rts_high = max_t(int, atmel_port->fifo_size >> 1, + atmel_port->fifo_size - ATMEL_RTS_HIGH_OFFSET); + atmel_port->rts_low = max_t(int, atmel_port->fifo_size >> 2, + atmel_port->fifo_size - ATMEL_RTS_LOW_OFFSET); dev_info(&pdev->dev, "Using FIFO (%u data)\n", - port->fifo_size); + atmel_port->fifo_size); dev_dbg(&pdev->dev, "RTS High Threshold : %2u data\n", - port->rts_high); + atmel_port->rts_high); dev_dbg(&pdev->dev, "RTS Low Threshold : %2u data\n", - port->rts_low); + atmel_port->rts_low); } static int atmel_serial_probe(struct platform_device *pdev) { - struct atmel_uart_port *port; + struct atmel_uart_port *atmel_port; struct device_node *np = pdev->dev.of_node; struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev); void *data; @@ -2674,99 +2682,133 @@ static int atmel_serial_probe(struct platform_device *pdev) goto err; } - port = &atmel_ports[ret]; - port->backup_imr = 0; - port->uart.line = ret; - atmel_serial_probe_fifos(port, pdev); + atmel_port = &atmel_ports[ret]; + atmel_port->backup_imr = 0; + atmel_port->uart.line = ret; + atmel_serial_probe_fifos(atmel_port, pdev); - spin_lock_init(&port->lock_suspended); + spin_lock_init(&atmel_port->lock_suspended); - ret = atmel_init_port(port, pdev); + ret = atmel_init_port(atmel_port, pdev); if (ret) goto err_clear_bit; - port->gpios = mctrl_gpio_init(&port->uart, 0); - if (IS_ERR(port->gpios)) { - ret = PTR_ERR(port->gpios); + atmel_port->gpios = mctrl_gpio_init(&atmel_port->uart, 0); + if (IS_ERR(atmel_port->gpios)) { + ret = PTR_ERR(atmel_port->gpios); goto err_clear_bit; } - if (!atmel_use_pdc_rx(&port->uart)) { + if (!atmel_use_pdc_rx(&atmel_port->uart)) { ret = -ENOMEM; data = kmalloc(sizeof(struct atmel_uart_char) * ATMEL_SERIAL_RINGSIZE, GFP_KERNEL); if (!data) goto err_alloc_ring; - port->rx_ring.buf = data; + atmel_port->rx_ring.buf = data; } - rs485_enabled = port->uart.rs485.flags & SER_RS485_ENABLED; + rs485_enabled = atmel_port->uart.rs485.flags & SER_RS485_ENABLED; - ret = uart_add_one_port(&atmel_uart, &port->uart); + ret = uart_add_one_port(&atmel_uart, &atmel_port->uart); if (ret) goto err_add_port; #ifdef CONFIG_SERIAL_ATMEL_CONSOLE - if (atmel_is_console_port(&port->uart) + if (atmel_is_console_port(&atmel_port->uart) && ATMEL_CONSOLE_DEVICE->flags & CON_ENABLED) { /* * The serial core enabled the clock for us, so undo * the clk_prepare_enable() in atmel_console_setup() */ - clk_disable_unprepare(port->clk); + clk_disable_unprepare(atmel_port->clk); } #endif device_init_wakeup(&pdev->dev, 1); - platform_set_drvdata(pdev, port); + platform_set_drvdata(pdev, atmel_port); /* * The peripheral clock has been disabled by atmel_init_port(): * enable it before accessing I/O registers */ - clk_prepare_enable(port->clk); + clk_prepare_enable(atmel_port->clk); if (rs485_enabled) { - atmel_uart_writel(&port->uart, ATMEL_US_MR, + atmel_uart_writel(&atmel_port->uart, ATMEL_US_MR, ATMEL_US_USMODE_NORMAL); - atmel_uart_writel(&port->uart, ATMEL_US_CR, ATMEL_US_RTSEN); + atmel_uart_writel(&atmel_port->uart, ATMEL_US_CR, + ATMEL_US_RTSEN); } /* * Get port name of usart or uart */ - atmel_get_ip_name(&port->uart); + atmel_get_ip_name(&atmel_port->uart); /* * The peripheral clock can now safely be disabled till the port * is used */ - clk_disable_unprepare(port->clk); + clk_disable_unprepare(atmel_port->clk); return 0; err_add_port: - kfree(port->rx_ring.buf); - port->rx_ring.buf = NULL; + kfree(atmel_port->rx_ring.buf); + atmel_port->rx_ring.buf = NULL; err_alloc_ring: - if (!atmel_is_console_port(&port->uart)) { - clk_put(port->clk); - port->clk = NULL; + if (!atmel_is_console_port(&atmel_port->uart)) { + clk_put(atmel_port->clk); + atmel_port->clk = NULL; } err_clear_bit: - clear_bit(port->uart.line, atmel_ports_in_use); + clear_bit(atmel_port->uart.line, atmel_ports_in_use); err: return ret; } +/* + * Even if the driver is not modular, it makes sense to be able to + * unbind a device: there can be many bound devices, and there are + * situations where dynamic binding and unbinding can be useful. + * + * For example, a connected device can require a specific firmware update + * protocol that needs bitbanging on IO lines, but use the regular serial + * port in the normal case. + */ +static int atmel_serial_remove(struct platform_device *pdev) +{ + struct uart_port *port = platform_get_drvdata(pdev); + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + int ret = 0; + + tasklet_kill(&atmel_port->tasklet); + + device_init_wakeup(&pdev->dev, 0); + + ret = uart_remove_one_port(&atmel_uart, port); + + kfree(atmel_port->rx_ring.buf); + + /* "port" is allocated statically, so we shouldn't free it */ + + clear_bit(port->line, atmel_ports_in_use); + + clk_put(atmel_port->clk); + atmel_port->clk = NULL; + + return ret; +} + static struct platform_driver atmel_serial_driver = { .probe = atmel_serial_probe, + .remove = atmel_serial_remove, .suspend = atmel_serial_suspend, .resume = atmel_serial_resume, .driver = { .name = "atmel_usart", .of_match_table = of_match_ptr(atmel_serial_dt_ids), - .suppress_bind_attrs = true, }, }; |