TTY/Serial fixes for 4.13-rc2

Here are some small tty and serial driver fixes for 4.13-rc2.  Nothing
 huge at all, a revert of a patch that turned out to break things, a fix
 up for a new tty ioctl we added in 4.13-rc1 to get the uapi definition
 correct, and a few minor serial driver fixes for reported issues.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 4.13-rc2. Nothing
  huge at all, a revert of a patch that turned out to break things, a
  fix up for a new tty ioctl we added in 4.13-rc1 to get the uapi
  definition correct, and a few minor serial driver fixes for reported
  issues.

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

* tag 'tty-4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: Fix TIOCGPTPEER ioctl definition
  tty: hide unused pty_get_peer function
  tty: serial: lpuart: Fix the logic for detecting the 32-bit type UART
  serial: imx: Prevent TX buffer PIO write when a DMA has been started
  Revert "serial: imx-serial - move DMA buffer configuration to DT"
  serial: sh-sci: Uninitialized variables in sysfs files
  serial: st-asc: Potential error pointer dereference

Documentation/devicetree/bindings/serial/fsl-imx-uart.txt

@@ -9,7 +9,6 @@ Optional properties:
 - fsl,irda-mode : Indicate the uart supports irda mode
 - fsl,dte-mode : Indicate the uart works in DTE mode. The uart works
                   in DCE mode by default.
-- fsl,dma-size : Indicate the size of the DMA buffer and its periods
 
 Please check Documentation/devicetree/bindings/serial/serial.txt
 for the complete list of generic properties.
@@ -29,5 +28,4 @@ uart1: serial@73fbc000 {
 	interrupts = <31>;
 	uart-has-rtscts;
 	fsl,dte-mode;
-	fsl,dma-size = <1024 4>;
 };

arch/alpha/include/uapi/asm/ioctls.h

@@ -100,7 +100,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define TIOCSERCONFIG	0x5453
 #define TIOCSERGWILD	0x5454

arch/mips/include/uapi/asm/ioctls.h

@@ -91,7 +91,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 /* I hope the range from 0x5480 on is free ... */
 #define TIOCSCTTY	0x5480		/* become controlling tty */

arch/parisc/include/uapi/asm/ioctls.h

@@ -60,7 +60,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451

arch/powerpc/include/uapi/asm/ioctls.h

@@ -100,7 +100,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define TIOCSERCONFIG	0x5453
 #define TIOCSERGWILD	0x5454

arch/sh/include/uapi/asm/ioctls.h

@@ -93,7 +93,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define TIOCSERCONFIG	_IO('T', 83) /* 0x5453 */
 #define TIOCSERGWILD	_IOR('T', 84,  int) /* 0x5454 */

arch/sparc/include/uapi/asm/ioctls.h

@@ -88,7 +88,7 @@
 #define TIOCGPTN	_IOR('t', 134, unsigned int) /* Get Pty Number */
 #define TIOCSPTLCK	_IOW('t', 135, int) /* Lock/unlock PTY */
 #define TIOCSIG		_IOW('t', 136, int) /* Generate signal on Pty slave */
-#define TIOCGPTPEER	_IOR('t', 137, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('t', 137) /* Safely open the slave */
 
 /* Little f */
 #define FIOCLEX		_IO('f', 1)

arch/xtensa/include/uapi/asm/ioctls.h

@@ -105,7 +105,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define TIOCSERCONFIG	_IO('T', 83)
 #define TIOCSERGWILD	_IOR('T', 84,  int)

drivers/tty/pty.c

@@ -448,48 +448,6 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
 	return retval;
 }
 
-/**
- *	pty_open_peer - open the peer of a pty
- *	@tty: the peer of the pty being opened
- *
- *	Open the cached dentry in tty->link, providing a safe way for userspace
- *	to get the slave end of a pty (where they have the master fd and cannot
- *	access or trust the mount namespace /dev/pts was mounted inside).
- */
-static struct file *pty_open_peer(struct tty_struct *tty, int flags)
-{
-	if (tty->driver->subtype != PTY_TYPE_MASTER)
-		return ERR_PTR(-EIO);
-	return dentry_open(tty->link->driver_data, flags, current_cred());
-}
-
-static int pty_get_peer(struct tty_struct *tty, int flags)
-{
-	int fd = -1;
-	struct file *filp = NULL;
-	int retval = -EINVAL;
-
-	fd = get_unused_fd_flags(0);
-	if (fd < 0) {
-		retval = fd;
-		goto err;
-	}
-
-	filp = pty_open_peer(tty, flags);
-	if (IS_ERR(filp)) {
-		retval = PTR_ERR(filp);
-		goto err_put;
-	}
-
-	fd_install(fd, filp);
-	return fd;
-
-err_put:
-	put_unused_fd(fd);
-err:
-	return retval;
-}
-
 static void pty_cleanup(struct tty_struct *tty)
 {
 	tty_port_put(tty->port);
@@ -646,9 +604,50 @@ static inline void legacy_pty_init(void) { }
 
 /* Unix98 devices */
 #ifdef CONFIG_UNIX98_PTYS
-
 static struct cdev ptmx_cdev;
 
+/**
+ *	pty_open_peer - open the peer of a pty
+ *	@tty: the peer of the pty being opened
+ *
+ *	Open the cached dentry in tty->link, providing a safe way for userspace
+ *	to get the slave end of a pty (where they have the master fd and cannot
+ *	access or trust the mount namespace /dev/pts was mounted inside).
+ */
+static struct file *pty_open_peer(struct tty_struct *tty, int flags)
+{
+	if (tty->driver->subtype != PTY_TYPE_MASTER)
+		return ERR_PTR(-EIO);
+	return dentry_open(tty->link->driver_data, flags, current_cred());
+}
+
+static int pty_get_peer(struct tty_struct *tty, int flags)
+{
+	int fd = -1;
+	struct file *filp = NULL;
+	int retval = -EINVAL;
+
+	fd = get_unused_fd_flags(0);
+	if (fd < 0) {
+		retval = fd;
+		goto err;
+	}
+
+	filp = pty_open_peer(tty, flags);
+	if (IS_ERR(filp)) {
+		retval = PTR_ERR(filp);
+		goto err_put;
+	}
+
+	fd_install(fd, filp);
+	return fd;
+
+err_put:
+	put_unused_fd(fd);
+err:
+	return retval;
+}
+
 static int pty_unix98_ioctl(struct tty_struct *tty,
 			    unsigned int cmd, unsigned long arg)
 {

drivers/tty/serial/fsl_lpuart.c

@@ -619,6 +619,12 @@ static unsigned int lpuart32_tx_empty(struct uart_port *port)
 		TIOCSER_TEMT : 0;
 }
 
+static bool lpuart_is_32(struct lpuart_port *sport)
+{
+	return sport->port.iotype == UPIO_MEM32 ||
+	       sport->port.iotype ==  UPIO_MEM32BE;
+}
+
 static irqreturn_t lpuart_txint(int irq, void *dev_id)
 {
 	struct lpuart_port *sport = dev_id;
@@ -627,7 +633,7 @@ static irqreturn_t lpuart_txint(int irq, void *dev_id)
 
 	spin_lock_irqsave(&sport->port.lock, flags);
 	if (sport->port.x_char) {
-		if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+		if (lpuart_is_32(sport))
 			lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
 		else
 			writeb(sport->port.x_char, sport->port.membase + UARTDR);
@@ -635,14 +641,14 @@ static irqreturn_t lpuart_txint(int irq, void *dev_id)
 	}
 
 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
-		if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+		if (lpuart_is_32(sport))
 			lpuart32_stop_tx(&sport->port);
 		else
 			lpuart_stop_tx(&sport->port);
 		goto out;
 	}
 
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+	if (lpuart_is_32(sport))
 		lpuart32_transmit_buffer(sport);
 	else
 		lpuart_transmit_buffer(sport);
@@ -1978,12 +1984,12 @@ static int __init lpuart_console_setup(struct console *co, char *options)
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 	else
-		if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+		if (lpuart_is_32(sport))
 			lpuart32_console_get_options(sport, &baud, &parity, &bits);
 		else
 			lpuart_console_get_options(sport, &baud, &parity, &bits);
 
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+	if (lpuart_is_32(sport))
 		lpuart32_setup_watermark(sport);
 	else
 		lpuart_setup_watermark(sport);
@@ -2118,7 +2124,7 @@ static int lpuart_probe(struct platform_device *pdev)
 	}
 	sport->port.irq = ret;
 	sport->port.iotype = sdata->iotype;
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+	if (lpuart_is_32(sport))
 		sport->port.ops = &lpuart32_pops;
 	else
 		sport->port.ops = &lpuart_pops;
@@ -2145,7 +2151,7 @@ static int lpuart_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, &sport->port);
 
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+	if (lpuart_is_32(sport))
 		lpuart_reg.cons = LPUART32_CONSOLE;
 	else
 		lpuart_reg.cons = LPUART_CONSOLE;
@@ -2198,7 +2204,7 @@ static int lpuart_suspend(struct device *dev)
 	struct lpuart_port *sport = dev_get_drvdata(dev);
 	unsigned long temp;
 
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
+	if (lpuart_is_32(sport)) {
 		/* disable Rx/Tx and interrupts */
 		temp = lpuart32_read(&sport->port, UARTCTRL);
 		temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
@@ -2249,7 +2255,7 @@ static int lpuart_resume(struct device *dev)
 	if (sport->port.suspended && !sport->port.irq_wake)
 		clk_prepare_enable(sport->clk);
 
-	if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
+	if (lpuart_is_32(sport)) {
 		lpuart32_setup_watermark(sport);
 		temp = lpuart32_read(&sport->port, UARTCTRL);
 		temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE |

drivers/tty/serial/imx.c

@@ -186,11 +186,6 @@
 
 #define UART_NR 8
 
-/* RX DMA buffer periods */
-#define RX_DMA_PERIODS 4
-#define RX_BUF_SIZE	(PAGE_SIZE)
-
-
 /* i.MX21 type uart runs on all i.mx except i.MX1 and i.MX6q */
 enum imx_uart_type {
 	IMX1_UART,
@@ -226,7 +221,6 @@ struct imx_port {
 	struct dma_chan		*dma_chan_rx, *dma_chan_tx;
 	struct scatterlist	rx_sgl, tx_sgl[2];
 	void			*rx_buf;
-	unsigned int		rx_buf_size;
 	struct circ_buf		rx_ring;
 	unsigned int		rx_periods;
 	dma_cookie_t		rx_cookie;
@@ -464,7 +458,7 @@ static inline void imx_transmit_buffer(struct imx_port *sport)
 		}
 	}
 
-	while (!uart_circ_empty(xmit) &&
+	while (!uart_circ_empty(xmit) && !sport->dma_is_txing &&
 	       !(readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)) {
 		/* send xmit->buf[xmit->tail]
 		 * out the port here */
@@ -967,6 +961,8 @@ static void imx_timeout(unsigned long data)
 	}
 }
 
+#define RX_BUF_SIZE	(PAGE_SIZE)
+
 /*
  * There are two kinds of RX DMA interrupts(such as in the MX6Q):
  *   [1] the RX DMA buffer is full.
@@ -1049,6 +1045,9 @@ static void dma_rx_callback(void *data)
 	}
 }
 
+/* RX DMA buffer periods */
+#define RX_DMA_PERIODS 4
+
 static int start_rx_dma(struct imx_port *sport)
 {
 	struct scatterlist *sgl = &sport->rx_sgl;
@@ -1059,8 +1058,9 @@ static int start_rx_dma(struct imx_port *sport)
 
 	sport->rx_ring.head = 0;
 	sport->rx_ring.tail = 0;
+	sport->rx_periods = RX_DMA_PERIODS;
 
-	sg_init_one(sgl, sport->rx_buf, sport->rx_buf_size);
+	sg_init_one(sgl, sport->rx_buf, RX_BUF_SIZE);
 	ret = dma_map_sg(dev, sgl, 1, DMA_FROM_DEVICE);
 	if (ret == 0) {
 		dev_err(dev, "DMA mapping error for RX.\n");
@@ -1171,7 +1171,7 @@ static int imx_uart_dma_init(struct imx_port *sport)
 		goto err;
 	}
 
-	sport->rx_buf = kzalloc(sport->rx_buf_size, GFP_KERNEL);
+	sport->rx_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!sport->rx_buf) {
 		ret = -ENOMEM;
 		goto err;
@@ -2036,7 +2036,6 @@ static int serial_imx_probe_dt(struct imx_port *sport,
 {
 	struct device_node *np = pdev->dev.of_node;
 	int ret;
-	u32 dma_buf_size[2];
 
 	sport->devdata = of_device_get_match_data(&pdev->dev);
 	if (!sport->devdata)
@@ -2060,14 +2059,6 @@ static int serial_imx_probe_dt(struct imx_port *sport,
 	if (of_get_property(np, "rts-gpios", NULL))
 		sport->have_rtsgpio = 1;
 
-	if (!of_property_read_u32_array(np, "fsl,dma-size", dma_buf_size, 2)) {
-		sport->rx_buf_size = dma_buf_size[0] * dma_buf_size[1];
-		sport->rx_periods = dma_buf_size[1];
-	} else {
-		sport->rx_buf_size = RX_BUF_SIZE;
-		sport->rx_periods = RX_DMA_PERIODS;
-	}
-
 	return 0;
 }
 #else

drivers/tty/serial/sh-sci.c

@@ -1085,10 +1085,12 @@ static ssize_t rx_trigger_store(struct device *dev,
 {
 	struct uart_port *port = dev_get_drvdata(dev);
 	struct sci_port *sci = to_sci_port(port);
+	int ret;
 	long r;
 
-	if (kstrtol(buf, 0, &r) == -EINVAL)
+	ret = kstrtol(buf, 0, &r);
-		return -EINVAL;
+	if (ret)
+		return ret;
 
 	sci->rx_trigger = scif_set_rtrg(port, r);
 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
@@ -1116,10 +1118,12 @@ static ssize_t rx_fifo_timeout_store(struct device *dev,
 {
 	struct uart_port *port = dev_get_drvdata(dev);
 	struct sci_port *sci = to_sci_port(port);
+	int ret;
 	long r;
 
-	if (kstrtol(buf, 0, &r) == -EINVAL)
+	ret = kstrtol(buf, 0, &r);
-		return -EINVAL;
+	if (ret)
+		return ret;
 	sci->rx_fifo_timeout = r;
 	scif_set_rtrg(port, 1);
 	if (r > 0)

drivers/tty/serial/st-asc.c

@@ -758,6 +758,7 @@ static int asc_init_port(struct asc_port *ascport,
 	if (IS_ERR(ascport->pinctrl)) {
 		ret = PTR_ERR(ascport->pinctrl);
 		dev_err(&pdev->dev, "Failed to get Pinctrl: %d\n", ret);
+		return ret;
 	}
 
 	ascport->states[DEFAULT] =

include/uapi/asm-generic/ioctls.h

@@ -77,7 +77,7 @@
 #define TIOCGPKT	_IOR('T', 0x38, int) /* Get packet mode state */
 #define TIOCGPTLCK	_IOR('T', 0x39, int) /* Get Pty lock state */
 #define TIOCGEXCL	_IOR('T', 0x40, int) /* Get exclusive mode state */
-#define TIOCGPTPEER	_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER	_IO('T', 0x41) /* Safely open the slave */
 
 #define FIONCLEX	0x5450
 #define FIOCLEX		0x5451