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-rw-r--r--drivers/tty/n_gsm.c23
-rw-r--r--drivers/tty/serial/earlycon.c6
-rw-r--r--drivers/tty/serial/imx.c19
-rw-r--r--drivers/tty/serial/mvebu-uart.c1
-rw-r--r--drivers/tty/serial/qcom_geni_serial.c10
-rw-r--r--drivers/tty/serial/xilinx_uartps.c2
-rw-r--r--drivers/tty/tty_io.c5
-rw-r--r--drivers/tty/tty_ldisc.c29
8 files changed, 68 insertions, 27 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 349c2e967bd1..86b7e20ffd7f 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -121,6 +121,9 @@ struct gsm_dlci {
struct mutex mutex;
/* Link layer */
+ int mode;
+#define DLCI_MODE_ABM 0 /* Normal Asynchronous Balanced Mode */
+#define DLCI_MODE_ADM 1 /* Asynchronous Disconnected Mode */
spinlock_t lock; /* Protects the internal state */
struct timer_list t1; /* Retransmit timer for SABM and UA */
int retries;
@@ -1364,7 +1367,13 @@ retry:
ctrl->data = data;
ctrl->len = clen;
gsm->pending_cmd = ctrl;
- gsm->cretries = gsm->n2;
+
+ /* If DLCI0 is in ADM mode skip retries, it won't respond */
+ if (gsm->dlci[0]->mode == DLCI_MODE_ADM)
+ gsm->cretries = 1;
+ else
+ gsm->cretries = gsm->n2;
+
mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100);
gsm_control_transmit(gsm, ctrl);
spin_unlock_irqrestore(&gsm->control_lock, flags);
@@ -1472,6 +1481,7 @@ static void gsm_dlci_t1(struct timer_list *t)
if (debug & 8)
pr_info("DLCI %d opening in ADM mode.\n",
dlci->addr);
+ dlci->mode = DLCI_MODE_ADM;
gsm_dlci_open(dlci);
} else {
gsm_dlci_close(dlci);
@@ -2861,11 +2871,22 @@ static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk)
static int gsm_carrier_raised(struct tty_port *port)
{
struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port);
+ struct gsm_mux *gsm = dlci->gsm;
+
/* Not yet open so no carrier info */
if (dlci->state != DLCI_OPEN)
return 0;
if (debug & 2)
return 1;
+
+ /*
+ * Basic mode with control channel in ADM mode may not respond
+ * to CMD_MSC at all and modem_rx is empty.
+ */
+ if (gsm->encoding == 0 && gsm->dlci[0]->mode == DLCI_MODE_ADM &&
+ !dlci->modem_rx)
+ return 1;
+
return dlci->modem_rx & TIOCM_CD;
}
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index eb1f84258c44..149d0d0da65e 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -169,7 +169,7 @@ static int __init register_earlycon(char *buf, const struct earlycon_id *match)
*/
int __init setup_earlycon(char *buf)
{
- const struct earlycon_id *match;
+ const struct earlycon_id **p_match;
if (!buf || !buf[0])
return -EINVAL;
@@ -177,7 +177,9 @@ int __init setup_earlycon(char *buf)
if (early_con.flags & CON_ENABLED)
return -EALREADY;
- for (match = __earlycon_table; match < __earlycon_table_end; match++) {
+ for (p_match = __earlycon_table; p_match < __earlycon_table_end;
+ p_match++) {
+ const struct earlycon_id *match = *p_match;
size_t len = strlen(match->name);
if (strncmp(buf, match->name, len))
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index f370c1cf4f27..dd573d8ce087 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -316,7 +316,7 @@ static u32 imx_uart_readl(struct imx_port *sport, u32 offset)
* differ from the value that was last written. As it only
* clears after being set, reread conditionally.
*/
- if (sport->ucr2 & UCR2_SRST)
+ if (!(sport->ucr2 & UCR2_SRST))
sport->ucr2 = readl(sport->port.membase + offset);
return sport->ucr2;
break;
@@ -1833,6 +1833,11 @@ static int imx_uart_rs485_config(struct uart_port *port,
rs485conf->flags &= ~SER_RS485_ENABLED;
if (rs485conf->flags & SER_RS485_ENABLED) {
+ /* Enable receiver if low-active RTS signal is requested */
+ if (sport->have_rtscts && !sport->have_rtsgpio &&
+ !(rs485conf->flags & SER_RS485_RTS_ON_SEND))
+ rs485conf->flags |= SER_RS485_RX_DURING_TX;
+
/* disable transmitter */
ucr2 = imx_uart_readl(sport, UCR2);
if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
@@ -2265,6 +2270,18 @@ static int imx_uart_probe(struct platform_device *pdev)
(!sport->have_rtscts && !sport->have_rtsgpio))
dev_err(&pdev->dev, "no RTS control, disabling rs485\n");
+ /*
+ * If using the i.MX UART RTS/CTS control then the RTS (CTS_B)
+ * signal cannot be set low during transmission in case the
+ * receiver is off (limitation of the i.MX UART IP).
+ */
+ if (sport->port.rs485.flags & SER_RS485_ENABLED &&
+ sport->have_rtscts && !sport->have_rtsgpio &&
+ (!(sport->port.rs485.flags & SER_RS485_RTS_ON_SEND) &&
+ !(sport->port.rs485.flags & SER_RS485_RX_DURING_TX)))
+ dev_err(&pdev->dev,
+ "low-active RTS not possible when receiver is off, enabling receiver\n");
+
imx_uart_rs485_config(&sport->port, &sport->port.rs485);
/* Disable interrupts before requesting them */
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 013b86a1044f..d04b5eeea3c6 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -511,7 +511,6 @@ static void mvebu_uart_set_termios(struct uart_port *port,
termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR);
termios->c_cflag &= CREAD | CBAUD;
termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD);
- termios->c_lflag = old->c_lflag;
}
spin_unlock_irqrestore(&port->lock, flags);
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 66558d42d980..c3eb87c028a6 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -1022,6 +1022,7 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
struct qcom_geni_serial_port *port;
struct uart_port *uport;
struct resource *res;
+ int irq;
if (pdev->dev.of_node)
line = of_alias_get_id(pdev->dev.of_node, "serial");
@@ -1061,11 +1062,12 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
- uport->irq = platform_get_irq(pdev, 0);
- if (uport->irq < 0) {
- dev_err(&pdev->dev, "Failed to get IRQ %d\n", uport->irq);
- return uport->irq;
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Failed to get IRQ %d\n", irq);
+ return irq;
}
+ uport->irq = irq;
uport->private_data = &qcom_geni_console_driver;
platform_set_drvdata(pdev, port);
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 3e68d6302614..8a3e34234e98 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1142,7 +1142,7 @@ static int __init cdns_early_console_setup(struct earlycon_device *device,
/* only set baud if specified on command line - otherwise
* assume it has been initialized by a boot loader.
*/
- if (device->baud) {
+ if (port->uartclk && device->baud) {
u32 cd = 0, bdiv = 0;
u32 mr;
int div8;
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 63114ea35ec1..7c838b90a31d 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2816,7 +2816,10 @@ struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx)
kref_init(&tty->kref);
tty->magic = TTY_MAGIC;
- tty_ldisc_init(tty);
+ if (tty_ldisc_init(tty)) {
+ kfree(tty);
+ return NULL;
+ }
tty->session = NULL;
tty->pgrp = NULL;
mutex_init(&tty->legacy_mutex);
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 050f4d650891..fb7329ab2b37 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -176,12 +176,11 @@ static struct tty_ldisc *tty_ldisc_get(struct tty_struct *tty, int disc)
return ERR_CAST(ldops);
}
- ld = kmalloc(sizeof(struct tty_ldisc), GFP_KERNEL);
- if (ld == NULL) {
- put_ldops(ldops);
- return ERR_PTR(-ENOMEM);
- }
-
+ /*
+ * There is no way to handle allocation failure of only 16 bytes.
+ * Let's simplify error handling and save more memory.
+ */
+ ld = kmalloc(sizeof(struct tty_ldisc), GFP_KERNEL | __GFP_NOFAIL);
ld->ops = ldops;
ld->tty = tty;
@@ -527,19 +526,16 @@ static int tty_ldisc_failto(struct tty_struct *tty, int ld)
static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
{
/* There is an outstanding reference here so this is safe */
- old = tty_ldisc_get(tty, old->ops->num);
- WARN_ON(IS_ERR(old));
- tty->ldisc = old;
- tty_set_termios_ldisc(tty, old->ops->num);
- if (tty_ldisc_open(tty, old) < 0) {
- tty_ldisc_put(old);
+ if (tty_ldisc_failto(tty, old->ops->num) < 0) {
+ const char *name = tty_name(tty);
+
+ pr_warn("Falling back ldisc for %s.\n", name);
/* The traditional behaviour is to fall back to N_TTY, we
want to avoid falling back to N_NULL unless we have no
choice to avoid the risk of breaking anything */
if (tty_ldisc_failto(tty, N_TTY) < 0 &&
tty_ldisc_failto(tty, N_NULL) < 0)
- panic("Couldn't open N_NULL ldisc for %s.",
- tty_name(tty));
+ panic("Couldn't open N_NULL ldisc for %s.", name);
}
}
@@ -824,12 +820,13 @@ EXPORT_SYMBOL_GPL(tty_ldisc_release);
* the tty structure is not completely set up when this call is made.
*/
-void tty_ldisc_init(struct tty_struct *tty)
+int tty_ldisc_init(struct tty_struct *tty)
{
struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY);
if (IS_ERR(ld))
- panic("n_tty: init_tty");
+ return PTR_ERR(ld);
tty->ldisc = ld;
+ return 0;
}
/**