Merge tag 'tty-4.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyHEADmaster

Pull tty/serial fixes from Greg KH:
 "Here are some serial and tty fixes for 4.12-rc3. They are a bit bigger
  than normal, which is why I had them bake in linux-next for a few
  weeks and didn't send them to you for -rc2.

  They revert a few of the serdev patches from 4.12-rc1, and bring
  things back to how they were in 4.11, to try to make things a bit more
  stable there. Rob and Johan both agree that this is the way forward,
  so this isn't people squabbling over semantics. Other than that, just
  a few minor serial driver fixes that people have had problems with.

  All of these have been in linux-next for a few weeks with no reported
  issues"

* tag 'tty-4.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: altera_uart: call iounmap() at driver remove
  serial: imx: ensure UCR3 and UFCR are setup correctly
  MAINTAINERS/serial: Change maintainer of jsm driver
  serial: enable serdev support
  tty/serdev: add serdev registration interface
  serdev: Restore serdev_device_write_buf for atomic context
  serial: core: fix crash in uart_suspend_port
  tty: fix port buffer locking
  tty: ehv_bytechan: clean up init error handling
  serial: ifx6x60: fix use-after-free on module unload
  serial: altera_jtaguart: adding iounmap()
  serial: exar: Fix stuck MSIs
  serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'
  serdev: fix tty-port client deregistration
  Revert "tty_port: register tty ports with serdev bus"
  drivers/tty: 8250: only call fintek_8250_probe when doing port I/O

11 files changed, 141 insertions, 40 deletions

diff --git a/drivers/tty/ehv_bytechan.c b/drivers/tty/ehv_bytechan.c
index 7ac9bcdf1e61..61fe8d6fd24e 100644
--- a/drivers/tty/ehv_bytechan.c
+++ b/drivers/tty/ehv_bytechan.c
@@ -764,7 +764,7 @@ static int __init ehv_bc_init(void)
 	ehv_bc_driver = alloc_tty_driver(count);
 	if (!ehv_bc_driver) {
 		ret = -ENOMEM;
-		goto error;
+		goto err_free_bcs;
 	}
 
 	ehv_bc_driver->driver_name = "ehv-bc";
@@ -778,24 +778,23 @@ static int __init ehv_bc_init(void)
 	ret = tty_register_driver(ehv_bc_driver);
 	if (ret) {
 		pr_err("ehv-bc: could not register tty driver (ret=%i)\n", ret);
-		goto error;
+		goto err_put_tty_driver;
 	}
 
 	ret = platform_driver_register(&ehv_bc_tty_driver);
 	if (ret) {
 		pr_err("ehv-bc: could not register platform driver (ret=%i)\n",
 		       ret);
-		goto error;
+		goto err_deregister_tty_driver;
 	}
 
 	return 0;
 
-error:
-	if (ehv_bc_driver) {
-		tty_unregister_driver(ehv_bc_driver);
-		put_tty_driver(ehv_bc_driver);
-	}
-
+err_deregister_tty_driver:
+	tty_unregister_driver(ehv_bc_driver);
+err_put_tty_driver:
+	put_tty_driver(ehv_bc_driver);
+err_free_bcs:
 	kfree(bcs);
 
 	return ret;
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index 433de5ea9b02..f71b47334149 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -122,6 +122,18 @@ void serdev_device_write_wakeup(struct serdev_device *serdev)
 }
 EXPORT_SYMBOL_GPL(serdev_device_write_wakeup);
 
+int serdev_device_write_buf(struct serdev_device *serdev,
+			    const unsigned char *buf, size_t count)
+{
+	struct serdev_controller *ctrl = serdev->ctrl;
+
+	if (!ctrl || !ctrl->ops->write_buf)
+		return -EINVAL;
+
+	return ctrl->ops->write_buf(ctrl, buf, count);
+}
+EXPORT_SYMBOL_GPL(serdev_device_write_buf);
+
 int serdev_device_write(struct serdev_device *serdev,
 			const unsigned char *buf, size_t count,
 			unsigned long timeout)
diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c
index 487c88f6aa0e..d0a021c93986 100644
--- a/drivers/tty/serdev/serdev-ttyport.c
+++ b/drivers/tty/serdev/serdev-ttyport.c
@@ -102,9 +102,6 @@ static int ttyport_open(struct serdev_controller *ctrl)
 		return PTR_ERR(tty);
 	serport->tty = tty;
 
-	serport->port->client_ops = &client_ops;
-	serport->port->client_data = ctrl;
-
 	if (tty->ops->open)
 		tty->ops->open(serport->tty, NULL);
 	else
@@ -215,6 +212,7 @@ struct device *serdev_tty_port_register(struct tty_port *port,
 					struct device *parent,
 					struct tty_driver *drv, int idx)
 {
+	const struct tty_port_client_operations *old_ops;
 	struct serdev_controller *ctrl;
 	struct serport *serport;
 	int ret;
@@ -233,28 +231,37 @@ struct device *serdev_tty_port_register(struct tty_port *port,
 
 	ctrl->ops = &ctrl_ops;
 
+	old_ops = port->client_ops;
+	port->client_ops = &client_ops;
+	port->client_data = ctrl;
+
 	ret = serdev_controller_add(ctrl);
 	if (ret)
-		goto err_controller_put;
+		goto err_reset_data;
 
 	dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
 	return &ctrl->dev;
 
-err_controller_put:
+err_reset_data:
+	port->client_data = NULL;
+	port->client_ops = old_ops;
 	serdev_controller_put(ctrl);
+
 	return ERR_PTR(ret);
 }
 
-void serdev_tty_port_unregister(struct tty_port *port)
+int serdev_tty_port_unregister(struct tty_port *port)
 {
 	struct serdev_controller *ctrl = port->client_data;
 	struct serport *serport = serdev_controller_get_drvdata(ctrl);
 
 	if (!serport)
-		return;
+		return -ENODEV;
 
 	serdev_controller_remove(ctrl);
 	port->client_ops = NULL;
 	port->client_data = NULL;
 	serdev_controller_put(ctrl);
+
+	return 0;
 }
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 09a65a3ec7f7..68fd045a7025 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -47,6 +47,7 @@
 /*
  * These are definitions for the Exar XR17V35X and XR17(C|D)15X
  */
+#define UART_EXAR_INT0		0x80
 #define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
 #define UART_EXAR_DVID		0x8d	/* Device identification */
 
@@ -1337,7 +1338,7 @@ out_lock:
 	/*
 	 * Check if the device is a Fintek F81216A
 	 */
-	if (port->type == PORT_16550A)
+	if (port->type == PORT_16550A && port->iotype == UPIO_PORT)
 		fintek_8250_probe(up);
 
 	if (up->capabilities != old_capabilities) {
@@ -1869,17 +1870,13 @@ static int serial8250_default_handle_irq(struct uart_port *port)
 static int exar_handle_irq(struct uart_port *port)
 {
 	unsigned int iir = serial_port_in(port, UART_IIR);
-	int ret;
+	int ret = 0;
 
-	ret = serial8250_handle_irq(port, iir);
+	if (((port->type == PORT_XR17V35X) || (port->type == PORT_XR17D15X)) &&
+	    serial_port_in(port, UART_EXAR_INT0) != 0)
+		ret = 1;
 
-	if ((port->type == PORT_XR17V35X) ||
-	   (port->type == PORT_XR17D15X)) {
-		serial_port_in(port, 0x80);
-		serial_port_in(port, 0x81);
-		serial_port_in(port, 0x82);
-		serial_port_in(port, 0x83);
-	}
+	ret |= serial8250_handle_irq(port, iir);
 
 	return ret;
 }
@@ -2177,6 +2174,8 @@ int serial8250_do_startup(struct uart_port *port)
 	serial_port_in(port, UART_RX);
 	serial_port_in(port, UART_IIR);
 	serial_port_in(port, UART_MSR);
+	if ((port->type == PORT_XR17V35X) || (port->type == PORT_XR17D15X))
+		serial_port_in(port, UART_EXAR_INT0);
 
 	/*
 	 * At this point, there's no way the LSR could still be 0xff;
@@ -2335,6 +2334,8 @@ dont_test_tx_en:
 	serial_port_in(port, UART_RX);
 	serial_port_in(port, UART_IIR);
 	serial_port_in(port, UART_MSR);
+	if ((port->type == PORT_XR17V35X) || (port->type == PORT_XR17D15X))
+		serial_port_in(port, UART_EXAR_INT0);
 	up->lsr_saved_flags = 0;
 	up->msr_saved_flags = 0;
 
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index 18e3f8342b85..0475f5d261ce 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -478,6 +478,7 @@ static int altera_jtaguart_remove(struct platform_device *pdev)
 
 	port = &altera_jtaguart_ports[i].port;
 	uart_remove_one_port(&altera_jtaguart_driver, port);
+	iounmap(port->membase);
 
 	return 0;
 }
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 46d3438a0d27..3e4b717670d7 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -615,6 +615,7 @@ static int altera_uart_remove(struct platform_device *pdev)
 	if (port) {
 		uart_remove_one_port(&altera_uart_driver, port);
 		port->mapbase = 0;
+		iounmap(port->membase);
 	}
 
 	return 0;
diff --git a/drivers/tty/serial/efm32-uart.c b/drivers/tty/serial/efm32-uart.c
index ebd8569f9ad5..9fff25be87f9 100644
--- a/drivers/tty/serial/efm32-uart.c
+++ b/drivers/tty/serial/efm32-uart.c
@@ -27,6 +27,7 @@
 #define UARTn_FRAME		0x04
 #define UARTn_FRAME_DATABITS__MASK	0x000f
 #define UARTn_FRAME_DATABITS(n)		((n) - 3)
+#define UARTn_FRAME_PARITY__MASK	0x0300
 #define UARTn_FRAME_PARITY_NONE		0x0000
 #define UARTn_FRAME_PARITY_EVEN		0x0200
 #define UARTn_FRAME_PARITY_ODD		0x0300
@@ -572,12 +573,16 @@ static void efm32_uart_console_get_options(struct efm32_uart_port *efm_port,
 			16 * (4 + (clkdiv >> 6)));
 
 	frame = efm32_uart_read32(efm_port, UARTn_FRAME);
-	if (frame & UARTn_FRAME_PARITY_ODD)
+	switch (frame & UARTn_FRAME_PARITY__MASK) {
+	case UARTn_FRAME_PARITY_ODD:
 		*parity = 'o';
-	else if (frame & UARTn_FRAME_PARITY_EVEN)
+		break;
+	case UARTn_FRAME_PARITY_EVEN:
 		*parity = 'e';
-	else
+		break;
+	default:
 		*parity = 'n';
+	}
 
 	*bits = (frame & UARTn_FRAME_DATABITS__MASK) -
 			UARTn_FRAME_DATABITS(4) + 4;
diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 157883653256..f190a84a0246 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -1382,9 +1382,9 @@ static struct spi_driver ifx_spi_driver = {
 static void __exit ifx_spi_exit(void)
 {
 	/* unregister */
+	spi_unregister_driver(&ifx_spi_driver);
 	tty_unregister_driver(tty_drv);
 	put_tty_driver(tty_drv);
-	spi_unregister_driver(&ifx_spi_driver);
 	unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
 }
 
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 33509b4beaec..bbefddd92bfe 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -2184,7 +2184,9 @@ static int serial_imx_probe(struct platform_device *pdev)
 		 * and DCD (when they are outputs) or enables the respective
 		 * irqs. So set this bit early, i.e. before requesting irqs.
 		 */
-		writel(UFCR_DCEDTE, sport->port.membase + UFCR);
+		reg = readl(sport->port.membase + UFCR);
+		if (!(reg & UFCR_DCEDTE))
+			writel(reg | UFCR_DCEDTE, sport->port.membase + UFCR);
 
 		/*
 		 * Disable UCR3_RI and UCR3_DCD irqs. They are also not
@@ -2195,7 +2197,15 @@ static int serial_imx_probe(struct platform_device *pdev)
 		       sport->port.membase + UCR3);
 
 	} else {
-		writel(0, sport->port.membase + UFCR);
+		unsigned long ucr3 = UCR3_DSR;
+
+		reg = readl(sport->port.membase + UFCR);
+		if (reg & UFCR_DCEDTE)
+			writel(reg & ~UFCR_DCEDTE, sport->port.membase + UFCR);
+
+		if (!is_imx1_uart(sport))
+			ucr3 |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP;
+		writel(ucr3, sport->port.membase + UCR3);
 	}
 
 	clk_disable_unprepare(sport->clk_ipg);
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 0f45b7884a2c..13bfd5dcffce 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2083,7 +2083,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
 	mutex_lock(&port->mutex);
 
 	tty_dev = device_find_child(uport->dev, &match, serial_match_port);
-	if (device_may_wakeup(tty_dev)) {
+	if (tty_dev && device_may_wakeup(tty_dev)) {
 		if (!enable_irq_wake(uport->irq))
 			uport->irq_wake = 1;
 		put_device(tty_dev);
@@ -2782,7 +2782,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 	 * Register the port whether it's detected or not.  This allows
 	 * setserial to be used to alter this port's parameters.
 	 */
-	tty_dev = tty_port_register_device_attr(port, drv->tty_driver,
+	tty_dev = tty_port_register_device_attr_serdev(port, drv->tty_driver,
 			uport->line, uport->dev, port, uport->tty_groups);
 	if (likely(!IS_ERR(tty_dev))) {
 		device_set_wakeup_capable(tty_dev, 1);
@@ -2845,7 +2845,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 	/*
 	 * Remove the devices from the tty layer
 	 */
-	tty_unregister_device(drv->tty_driver, uport->line);
+	tty_port_unregister_device(port, drv->tty_driver, uport->line);
 
 	tty = tty_port_tty_get(port);
 	if (tty) {
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 1d21a9c1d33e..4fb3165384c4 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -34,7 +34,9 @@ static int tty_port_default_receive_buf(struct tty_port *port,
 	if (!disc)
 		return 0;
 
+	mutex_lock(&tty->atomic_write_lock);
 	ret = tty_ldisc_receive_buf(disc, p, (char *)f, count);
+	mutex_unlock(&tty->atomic_write_lock);
 
 	tty_ldisc_deref(disc);
 
@@ -129,19 +131,85 @@ struct device *tty_port_register_device_attr(struct tty_port *port,
 		struct device *device, void *drvdata,
 		const struct attribute_group **attr_grp)
 {
+	tty_port_link_device(port, driver, index);
+	return tty_register_device_attr(driver, index, device, drvdata,
+			attr_grp);
+}
+EXPORT_SYMBOL_GPL(tty_port_register_device_attr);
+
+/**
+ * tty_port_register_device_attr_serdev - register tty or serdev device
+ * @port: tty_port of the device
+ * @driver: tty_driver for this device
+ * @index: index of the tty
+ * @device: parent if exists, otherwise NULL
+ * @drvdata: driver data for the device
+ * @attr_grp: attribute group for the device
+ *
+ * Register a serdev or tty device depending on if the parent device has any
+ * defined serdev clients or not.
+ */
+struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
+		struct tty_driver *driver, unsigned index,
+		struct device *device, void *drvdata,
+		const struct attribute_group **attr_grp)
+{
 	struct device *dev;
 
 	tty_port_link_device(port, driver, index);
 
 	dev = serdev_tty_port_register(port, device, driver, index);
-	if (PTR_ERR(dev) != -ENODEV)
+	if (PTR_ERR(dev) != -ENODEV) {
 		/* Skip creating cdev if we registered a serdev device */
 		return dev;
+	}
 
 	return tty_register_device_attr(driver, index, device, drvdata,
 			attr_grp);
 }
-EXPORT_SYMBOL_GPL(tty_port_register_device_attr);
+EXPORT_SYMBOL_GPL(tty_port_register_device_attr_serdev);
+
+/**
+ * tty_port_register_device_serdev - register tty or serdev device
+ * @port: tty_port of the device
+ * @driver: tty_driver for this device
+ * @index: index of the tty
+ * @device: parent if exists, otherwise NULL
+ *
+ * Register a serdev or tty device depending on if the parent device has any
+ * defined serdev clients or not.
+ */
+struct device *tty_port_register_device_serdev(struct tty_port *port,
+		struct tty_driver *driver, unsigned index,
+		struct device *device)
+{
+	return tty_port_register_device_attr_serdev(port, driver, index,
+			device, NULL, NULL);
+}
+EXPORT_SYMBOL_GPL(tty_port_register_device_serdev);
+
+/**
+ * tty_port_unregister_device - deregister a tty or serdev device
+ * @port: tty_port of the device
+ * @driver: tty_driver for this device
+ * @index: index of the tty
+ *
+ * If a tty or serdev device is registered with a call to
+ * tty_port_register_device_serdev() then this function must be called when
+ * the device is gone.
+ */
+void tty_port_unregister_device(struct tty_port *port,
+		struct tty_driver *driver, unsigned index)
+{
+	int ret;
+
+	ret = serdev_tty_port_unregister(port);
+	if (ret == 0)
+		return;
+
+	tty_unregister_device(driver, index);
+}
+EXPORT_SYMBOL_GPL(tty_port_unregister_device);
 
 int tty_port_alloc_xmit_buf(struct tty_port *port)
 {
@@ -189,9 +257,6 @@ static void tty_port_destructor(struct kref *kref)
 	/* check if last port ref was dropped before tty release */
 	if (WARN_ON(port->itty))
 		return;
-
-	serdev_tty_port_unregister(port);
-
 	if (port->xmit_buf)
 		free_page((unsigned long)port->xmit_buf);
 	tty_port_destroy(port);