Merge tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver pull request for 4.6-rc1.

  Lots of changes in here, Peter has been on a tear again, with lots of
  refactoring and bugs fixes, many thanks to the great work he has been
  doing.  Lots of driver updates and fixes as well, full details in the
  shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (220 commits)
  serial: 8250: describe CONFIG_SERIAL_8250_RSA
  serial: samsung: optimize UART rx fifo access routine
  serial: pl011: add mark/space parity support
  serial: sa1100: make sa1100_register_uart_fns a function
  tty: serial: 8250: add MOXA Smartio MUE boards support
  serial: 8250: convert drivers to use up_to_u8250p()
  serial: 8250/mediatek: fix building with SERIAL_8250=m
  serial: 8250/ingenic: fix building with SERIAL_8250=m
  serial: 8250/uniphier: fix modular build
  Revert "drivers/tty/serial: make 8250/8250_ingenic.c explicitly non-modular"
  Revert "drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular"
  serial: mvebu-uart: initial support for Armada-3700 serial port
  serial: mctrl_gpio: Add missing module license
  serial: ifx6x60: avoid uninitialized variable use
  tty/serial: at91: fix bad offset for UART timeout register
  tty/serial: at91: restore dynamic driver binding
  serial: 8250: Add hardware dependency to RT288X option
  TTY, devpts: document pty count limiting
  tty: goldfish: support platform_device with id -1
  drivers: tty: goldfish: Add device tree bindings
  ...

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,
 	},
 };