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-rw-r--r--drivers/tty/n_hdlc.c132
-rw-r--r--drivers/tty/serial/8250/8250_dw.c9
-rw-r--r--drivers/tty/serial/amba-pl011.c2
-rw-r--r--drivers/tty/serial/samsung.c6
-rw-r--r--drivers/tty/serial/st-asc.c11
-rw-r--r--drivers/tty/tty_ldisc.c92
6 files changed, 108 insertions, 144 deletions
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 1bacbc3b19a0..e94aea8c0d05 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -114,7 +114,7 @@
#define DEFAULT_TX_BUF_COUNT 3
struct n_hdlc_buf {
- struct n_hdlc_buf *link;
+ struct list_head list_item;
int count;
char buf[1];
};
@@ -122,8 +122,7 @@ struct n_hdlc_buf {
#define N_HDLC_BUF_SIZE (sizeof(struct n_hdlc_buf) + maxframe)
struct n_hdlc_buf_list {
- struct n_hdlc_buf *head;
- struct n_hdlc_buf *tail;
+ struct list_head list;
int count;
spinlock_t spinlock;
};
@@ -136,7 +135,6 @@ struct n_hdlc_buf_list {
* @backup_tty - TTY to use if tty gets closed
* @tbusy - reentrancy flag for tx wakeup code
* @woke_up - FIXME: describe this field
- * @tbuf - currently transmitting tx buffer
* @tx_buf_list - list of pending transmit frame buffers
* @rx_buf_list - list of received frame buffers
* @tx_free_buf_list - list unused transmit frame buffers
@@ -149,7 +147,6 @@ struct n_hdlc {
struct tty_struct *backup_tty;
int tbusy;
int woke_up;
- struct n_hdlc_buf *tbuf;
struct n_hdlc_buf_list tx_buf_list;
struct n_hdlc_buf_list rx_buf_list;
struct n_hdlc_buf_list tx_free_buf_list;
@@ -159,6 +156,8 @@ struct n_hdlc {
/*
* HDLC buffer list manipulation functions
*/
+static void n_hdlc_buf_return(struct n_hdlc_buf_list *buf_list,
+ struct n_hdlc_buf *buf);
static void n_hdlc_buf_put(struct n_hdlc_buf_list *list,
struct n_hdlc_buf *buf);
static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *list);
@@ -208,16 +207,9 @@ static void flush_tx_queue(struct tty_struct *tty)
{
struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
struct n_hdlc_buf *buf;
- unsigned long flags;
while ((buf = n_hdlc_buf_get(&n_hdlc->tx_buf_list)))
n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, buf);
- spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags);
- if (n_hdlc->tbuf) {
- n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, n_hdlc->tbuf);
- n_hdlc->tbuf = NULL;
- }
- spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
}
static struct tty_ldisc_ops n_hdlc_ldisc = {
@@ -283,7 +275,6 @@ static void n_hdlc_release(struct n_hdlc *n_hdlc)
} else
break;
}
- kfree(n_hdlc->tbuf);
kfree(n_hdlc);
} /* end of n_hdlc_release() */
@@ -402,13 +393,7 @@ static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
n_hdlc->woke_up = 0;
spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
- /* get current transmit buffer or get new transmit */
- /* buffer from list of pending transmit buffers */
-
- tbuf = n_hdlc->tbuf;
- if (!tbuf)
- tbuf = n_hdlc_buf_get(&n_hdlc->tx_buf_list);
-
+ tbuf = n_hdlc_buf_get(&n_hdlc->tx_buf_list);
while (tbuf) {
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)sending frame %p, count=%d\n",
@@ -420,7 +405,7 @@ static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
/* rollback was possible and has been done */
if (actual == -ERESTARTSYS) {
- n_hdlc->tbuf = tbuf;
+ n_hdlc_buf_return(&n_hdlc->tx_buf_list, tbuf);
break;
}
/* if transmit error, throw frame away by */
@@ -435,10 +420,7 @@ static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
/* free current transmit buffer */
n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, tbuf);
-
- /* this tx buffer is done */
- n_hdlc->tbuf = NULL;
-
+
/* wait up sleeping writers */
wake_up_interruptible(&tty->write_wait);
@@ -448,10 +430,12 @@ static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)frame %p pending\n",
__FILE__,__LINE__,tbuf);
-
- /* buffer not accepted by driver */
- /* set this buffer as pending buffer */
- n_hdlc->tbuf = tbuf;
+
+ /*
+ * the buffer was not accepted by driver,
+ * return it back into tx queue
+ */
+ n_hdlc_buf_return(&n_hdlc->tx_buf_list, tbuf);
break;
}
}
@@ -749,7 +733,8 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
int error = 0;
int count;
unsigned long flags;
-
+ struct n_hdlc_buf *buf = NULL;
+
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_ioctl() called %d\n",
__FILE__,__LINE__,cmd);
@@ -763,8 +748,10 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
/* report count of read data available */
/* in next available frame (if any) */
spin_lock_irqsave(&n_hdlc->rx_buf_list.spinlock,flags);
- if (n_hdlc->rx_buf_list.head)
- count = n_hdlc->rx_buf_list.head->count;
+ buf = list_first_entry_or_null(&n_hdlc->rx_buf_list.list,
+ struct n_hdlc_buf, list_item);
+ if (buf)
+ count = buf->count;
else
count = 0;
spin_unlock_irqrestore(&n_hdlc->rx_buf_list.spinlock,flags);
@@ -776,8 +763,10 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
count = tty_chars_in_buffer(tty);
/* add size of next output frame in queue */
spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock,flags);
- if (n_hdlc->tx_buf_list.head)
- count += n_hdlc->tx_buf_list.head->count;
+ buf = list_first_entry_or_null(&n_hdlc->tx_buf_list.list,
+ struct n_hdlc_buf, list_item);
+ if (buf)
+ count += buf->count;
spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock,flags);
error = put_user(count, (int __user *)arg);
break;
@@ -825,14 +814,14 @@ static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp,
poll_wait(filp, &tty->write_wait, wait);
/* set bits for operations that won't block */
- if (n_hdlc->rx_buf_list.head)
+ if (!list_empty(&n_hdlc->rx_buf_list.list))
mask |= POLLIN | POLLRDNORM; /* readable */
if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
mask |= POLLHUP;
if (tty_hung_up_p(filp))
mask |= POLLHUP;
if (!tty_is_writelocked(tty) &&
- n_hdlc->tx_free_buf_list.head)
+ !list_empty(&n_hdlc->tx_free_buf_list.list))
mask |= POLLOUT | POLLWRNORM; /* writable */
}
return mask;
@@ -856,7 +845,12 @@ static struct n_hdlc *n_hdlc_alloc(void)
spin_lock_init(&n_hdlc->tx_free_buf_list.spinlock);
spin_lock_init(&n_hdlc->rx_buf_list.spinlock);
spin_lock_init(&n_hdlc->tx_buf_list.spinlock);
-
+
+ INIT_LIST_HEAD(&n_hdlc->rx_free_buf_list.list);
+ INIT_LIST_HEAD(&n_hdlc->tx_free_buf_list.list);
+ INIT_LIST_HEAD(&n_hdlc->rx_buf_list.list);
+ INIT_LIST_HEAD(&n_hdlc->tx_buf_list.list);
+
/* allocate free rx buffer list */
for(i=0;i<DEFAULT_RX_BUF_COUNT;i++) {
buf = kmalloc(N_HDLC_BUF_SIZE, GFP_KERNEL);
@@ -884,53 +878,65 @@ static struct n_hdlc *n_hdlc_alloc(void)
} /* end of n_hdlc_alloc() */
/**
+ * n_hdlc_buf_return - put the HDLC buffer after the head of the specified list
+ * @buf_list - pointer to the buffer list
+ * @buf - pointer to the buffer
+ */
+static void n_hdlc_buf_return(struct n_hdlc_buf_list *buf_list,
+ struct n_hdlc_buf *buf)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&buf_list->spinlock, flags);
+
+ list_add(&buf->list_item, &buf_list->list);
+ buf_list->count++;
+
+ spin_unlock_irqrestore(&buf_list->spinlock, flags);
+}
+
+/**
* n_hdlc_buf_put - add specified HDLC buffer to tail of specified list
- * @list - pointer to buffer list
+ * @buf_list - pointer to buffer list
* @buf - pointer to buffer
*/
-static void n_hdlc_buf_put(struct n_hdlc_buf_list *list,
+static void n_hdlc_buf_put(struct n_hdlc_buf_list *buf_list,
struct n_hdlc_buf *buf)
{
unsigned long flags;
- spin_lock_irqsave(&list->spinlock,flags);
-
- buf->link=NULL;
- if (list->tail)
- list->tail->link = buf;
- else
- list->head = buf;
- list->tail = buf;
- (list->count)++;
-
- spin_unlock_irqrestore(&list->spinlock,flags);
-
+
+ spin_lock_irqsave(&buf_list->spinlock, flags);
+
+ list_add_tail(&buf->list_item, &buf_list->list);
+ buf_list->count++;
+
+ spin_unlock_irqrestore(&buf_list->spinlock, flags);
} /* end of n_hdlc_buf_put() */
/**
* n_hdlc_buf_get - remove and return an HDLC buffer from list
- * @list - pointer to HDLC buffer list
+ * @buf_list - pointer to HDLC buffer list
*
* Remove and return an HDLC buffer from the head of the specified HDLC buffer
* list.
* Returns a pointer to HDLC buffer if available, otherwise %NULL.
*/
-static struct n_hdlc_buf* n_hdlc_buf_get(struct n_hdlc_buf_list *list)
+static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *buf_list)
{
unsigned long flags;
struct n_hdlc_buf *buf;
- spin_lock_irqsave(&list->spinlock,flags);
-
- buf = list->head;
+
+ spin_lock_irqsave(&buf_list->spinlock, flags);
+
+ buf = list_first_entry_or_null(&buf_list->list,
+ struct n_hdlc_buf, list_item);
if (buf) {
- list->head = buf->link;
- (list->count)--;
+ list_del(&buf->list_item);
+ buf_list->count--;
}
- if (!list->head)
- list->tail = NULL;
-
- spin_unlock_irqrestore(&list->spinlock,flags);
+
+ spin_unlock_irqrestore(&buf_list->spinlock, flags);
return buf;
-
} /* end of n_hdlc_buf_get() */
static char hdlc_banner[] __initdata =
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 6ee55a2d47bb..e65808c482f1 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -257,7 +257,7 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
{
unsigned int baud = tty_termios_baud_rate(termios);
struct dw8250_data *d = p->private_data;
- unsigned int rate;
+ long rate;
int ret;
if (IS_ERR(d->clk) || !old)
@@ -265,7 +265,12 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
clk_disable_unprepare(d->clk);
rate = clk_round_rate(d->clk, baud * 16);
- ret = clk_set_rate(d->clk, rate);
+ if (rate < 0)
+ ret = rate;
+ else if (rate == 0)
+ ret = -ENOENT;
+ else
+ ret = clk_set_rate(d->clk, rate);
clk_prepare_enable(d->clk);
if (!ret)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 8789ea423ccf..56f92d7348bf 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2373,7 +2373,7 @@ static int __init pl011_console_match(struct console *co, char *name, int idx,
if (strcmp(name, "qdf2400_e44") == 0) {
pr_info_once("UART: Working around QDF2400 SoC erratum 44");
qdf2400_e44_present = true;
- } else if (strcmp(name, "pl011") != 0 || strcmp(name, "ttyAMA") != 0) {
+ } else if (strcmp(name, "pl011") != 0) {
return -ENODEV;
}
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index b4f86c219db1..7a17aedbf902 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1031,8 +1031,10 @@ static int s3c64xx_serial_startup(struct uart_port *port)
if (ourport->dma) {
ret = s3c24xx_serial_request_dma(ourport);
if (ret < 0) {
- dev_warn(port->dev, "DMA request failed\n");
- return ret;
+ dev_warn(port->dev,
+ "DMA request failed, DMA will not be used\n");
+ devm_kfree(port->dev, ourport->dma);
+ ourport->dma = NULL;
}
}
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index bcf1d33e6ffe..c334bcc59c64 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -575,12 +575,13 @@ static void asc_set_termios(struct uart_port *port, struct ktermios *termios,
pinctrl_select_state(ascport->pinctrl,
ascport->states[NO_HW_FLOWCTRL]);
- gpiod = devm_get_gpiod_from_child(port->dev, "rts",
- &np->fwnode);
- if (!IS_ERR(gpiod)) {
- gpiod_direction_output(gpiod, 0);
+ gpiod = devm_fwnode_get_gpiod_from_child(port->dev,
+ "rts",
+ &np->fwnode,
+ GPIOD_OUT_LOW,
+ np->name);
+ if (!IS_ERR(gpiod))
ascport->rts = gpiod;
- }
}
}
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 68947f6de5ad..b0500a0a87b8 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -271,10 +271,13 @@ const struct file_operations tty_ldiscs_proc_fops = {
struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty)
{
+ struct tty_ldisc *ld;
+
ldsem_down_read(&tty->ldisc_sem, MAX_SCHEDULE_TIMEOUT);
- if (!tty->ldisc)
+ ld = tty->ldisc;
+ if (!ld)
ldsem_up_read(&tty->ldisc_sem);
- return tty->ldisc;
+ return ld;
}
EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait);
@@ -489,41 +492,6 @@ static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld)
}
/**
- * tty_ldisc_restore - helper for tty ldisc change
- * @tty: tty to recover
- * @old: previous ldisc
- *
- * Restore the previous line discipline or N_TTY when a line discipline
- * change fails due to an open error
- */
-
-static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
-{
- struct tty_ldisc *new_ldisc;
- int r;
-
- /* 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);
- /* This driver is always present */
- new_ldisc = tty_ldisc_get(tty, N_TTY);
- if (IS_ERR(new_ldisc))
- panic("n_tty: get");
- tty->ldisc = new_ldisc;
- tty_set_termios_ldisc(tty, N_TTY);
- r = tty_ldisc_open(tty, new_ldisc);
- if (r < 0)
- panic("Couldn't open N_TTY ldisc for "
- "%s --- error %d.",
- tty_name(tty), r);
- }
-}
-
-/**
* tty_set_ldisc - set line discipline
* @tty: the terminal to set
* @ldisc: the line discipline
@@ -536,12 +504,7 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
int tty_set_ldisc(struct tty_struct *tty, int disc)
{
- int retval;
- struct tty_ldisc *old_ldisc, *new_ldisc;
-
- new_ldisc = tty_ldisc_get(tty, disc);
- if (IS_ERR(new_ldisc))
- return PTR_ERR(new_ldisc);
+ int retval, old_disc;
tty_lock(tty);
retval = tty_ldisc_lock(tty, 5 * HZ);
@@ -554,7 +517,8 @@ int tty_set_ldisc(struct tty_struct *tty, int disc)
}
/* Check the no-op case */
- if (tty->ldisc->ops->num == disc)
+ old_disc = tty->ldisc->ops->num;
+ if (old_disc == disc)
goto out;
if (test_bit(TTY_HUPPED, &tty->flags)) {
@@ -563,34 +527,25 @@ int tty_set_ldisc(struct tty_struct *tty, int disc)
goto out;
}
- old_ldisc = tty->ldisc;
-
- /* Shutdown the old discipline. */
- tty_ldisc_close(tty, old_ldisc);
-
- /* Now set up the new line discipline. */
- tty->ldisc = new_ldisc;
- tty_set_termios_ldisc(tty, disc);
-
- retval = tty_ldisc_open(tty, new_ldisc);
+ retval = tty_ldisc_reinit(tty, disc);
if (retval < 0) {
/* Back to the old one or N_TTY if we can't */
- tty_ldisc_put(new_ldisc);
- tty_ldisc_restore(tty, old_ldisc);
+ if (tty_ldisc_reinit(tty, old_disc) < 0) {
+ pr_err("tty: TIOCSETD failed, reinitializing N_TTY\n");
+ if (tty_ldisc_reinit(tty, N_TTY) < 0) {
+ /* At this point we have tty->ldisc == NULL. */
+ pr_err("tty: reinitializing N_TTY failed\n");
+ }
+ }
}
- if (tty->ldisc->ops->num != old_ldisc->ops->num && tty->ops->set_ldisc) {
+ if (tty->ldisc && tty->ldisc->ops->num != old_disc &&
+ tty->ops->set_ldisc) {
down_read(&tty->termios_rwsem);
tty->ops->set_ldisc(tty);
up_read(&tty->termios_rwsem);
}
- /* At this point we hold a reference to the new ldisc and a
- reference to the old ldisc, or we hold two references to
- the old ldisc (if it was restored as part of error cleanup
- above). In either case, releasing a single reference from
- the old ldisc is correct. */
- new_ldisc = old_ldisc;
out:
tty_ldisc_unlock(tty);
@@ -598,7 +553,6 @@ out:
already running */
tty_buffer_restart_work(tty->port);
err:
- tty_ldisc_put(new_ldisc); /* drop the extra reference */
tty_unlock(tty);
return retval;
}
@@ -659,10 +613,8 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc)
int retval;
ld = tty_ldisc_get(tty, disc);
- if (IS_ERR(ld)) {
- BUG_ON(disc == N_TTY);
+ if (IS_ERR(ld))
return PTR_ERR(ld);
- }
if (tty->ldisc) {
tty_ldisc_close(tty, tty->ldisc);
@@ -674,10 +626,8 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc)
tty_set_termios_ldisc(tty, disc);
retval = tty_ldisc_open(tty, tty->ldisc);
if (retval) {
- if (!WARN_ON(disc == N_TTY)) {
- tty_ldisc_put(tty->ldisc);
- tty->ldisc = NULL;
- }
+ tty_ldisc_put(tty->ldisc);
+ tty->ldisc = NULL;
}
return retval;
}
generated by cgit (git 2.34.1) at 2024-05-28 15:23:39 +0000