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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-27 10:39:09 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-27 10:39:09 -0700 |
commit | a8d706986c5ee65354d8ddd88fe2dadfd2184991 (patch) | |
tree | 274e9e68933010e179673e35d635c4acef51eb56 /drivers | |
parent | d0c15ad760c869f3d676b37c2989baa1566d31f1 (diff) | |
parent | 7deb39ed8d9494ea541bcaa69b56036a94f79dc2 (diff) | |
download | linux-stable-a8d706986c5ee65354d8ddd88fe2dadfd2184991.tar.gz linux-stable-a8d706986c5ee65354d8ddd88fe2dadfd2184991.tar.bz2 linux-stable-a8d706986c5ee65354d8ddd88fe2dadfd2184991.zip |
Merge tag 'tty-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a few tty/serial fixes for 3.15-rc3 that resolve a number of
reported issues in the 8250 and samsung serial drivers, as well as a
character loss fix for the tty core that was caused by the lock
removal patches a release ago"
* tag 'tty-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial_core: fix uart PORT_UNKNOWN handling
serial: samsung: Change barrier() to cpu_relax() in console output
serial: samsung: don't check config for every character
serial: samsung: Use the passed in "port", fixing kgdb w/ no console
serial: 8250: Fix thread unsafe __dma_tx_complete function
8250_core: Fix unwanted TX chars write
tty: Fix race condition between __tty_buffer_request_room and flush_to_ldisc
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 2 | ||||
-rw-r--r-- | drivers/tty/serial/8250/8250_dma.c | 9 | ||||
-rw-r--r-- | drivers/tty/serial/samsung.c | 23 | ||||
-rw-r--r-- | drivers/tty/serial/serial_core.c | 39 | ||||
-rw-r--r-- | drivers/tty/tty_buffer.c | 16 |
5 files changed, 55 insertions, 34 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 81f909c2101f..0e1bf8858431 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1520,7 +1520,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) status = serial8250_rx_chars(up, status); } serial8250_modem_status(up); - if (status & UART_LSR_THRE) + if (!up->dma && (status & UART_LSR_THRE)) serial8250_tx_chars(up); spin_unlock_irqrestore(&port->lock, flags); diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index 7046769608d4..ab9096dc3849 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -20,12 +20,15 @@ static void __dma_tx_complete(void *param) struct uart_8250_port *p = param; struct uart_8250_dma *dma = p->dma; struct circ_buf *xmit = &p->port.state->xmit; - - dma->tx_running = 0; + unsigned long flags; dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr, UART_XMIT_SIZE, DMA_TO_DEVICE); + spin_lock_irqsave(&p->port.lock, flags); + + dma->tx_running = 0; + xmit->tail += dma->tx_size; xmit->tail &= UART_XMIT_SIZE - 1; p->port.icount.tx += dma->tx_size; @@ -35,6 +38,8 @@ static void __dma_tx_complete(void *param) if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) serial8250_tx_dma(p); + + spin_unlock_irqrestore(&p->port.lock, flags); } static void __dma_rx_complete(void *param) diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 23f459600738..1f5505e7f90d 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -1446,8 +1446,8 @@ static int s3c24xx_serial_get_poll_char(struct uart_port *port) static void s3c24xx_serial_put_poll_char(struct uart_port *port, unsigned char c) { - unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON); - unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON); + unsigned int ufcon = rd_regl(port, S3C2410_UFCON); + unsigned int ucon = rd_regl(port, S3C2410_UCON); /* not possible to xmit on unconfigured port */ if (!s3c24xx_port_configured(ucon)) @@ -1455,7 +1455,7 @@ static void s3c24xx_serial_put_poll_char(struct uart_port *port, while (!s3c24xx_serial_console_txrdy(port, ufcon)) cpu_relax(); - wr_regb(cons_uart, S3C2410_UTXH, c); + wr_regb(port, S3C2410_UTXH, c); } #endif /* CONFIG_CONSOLE_POLL */ @@ -1463,22 +1463,23 @@ static void s3c24xx_serial_put_poll_char(struct uart_port *port, static void s3c24xx_serial_console_putchar(struct uart_port *port, int ch) { - unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON); - unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON); - - /* not possible to xmit on unconfigured port */ - if (!s3c24xx_port_configured(ucon)) - return; + unsigned int ufcon = rd_regl(port, S3C2410_UFCON); while (!s3c24xx_serial_console_txrdy(port, ufcon)) - barrier(); - wr_regb(cons_uart, S3C2410_UTXH, ch); + cpu_relax(); + wr_regb(port, S3C2410_UTXH, ch); } static void s3c24xx_serial_console_write(struct console *co, const char *s, unsigned int count) { + unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON); + + /* not possible to xmit on unconfigured port */ + if (!s3c24xx_port_configured(ucon)) + return; + uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar); } diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index f26834d262b3..b68550d95a40 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -137,6 +137,11 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state, return 1; /* + * Make sure the device is in D0 state. + */ + uart_change_pm(state, UART_PM_STATE_ON); + + /* * Initialise and allocate the transmit and temporary * buffer. */ @@ -825,25 +830,29 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, * If we fail to request resources for the * new port, try to restore the old settings. */ - if (retval && old_type != PORT_UNKNOWN) { + if (retval) { uport->iobase = old_iobase; uport->type = old_type; uport->hub6 = old_hub6; uport->iotype = old_iotype; uport->regshift = old_shift; uport->mapbase = old_mapbase; - retval = uport->ops->request_port(uport); - /* - * If we failed to restore the old settings, - * we fail like this. - */ - if (retval) - uport->type = PORT_UNKNOWN; - /* - * We failed anyway. - */ - retval = -EBUSY; + if (old_type != PORT_UNKNOWN) { + retval = uport->ops->request_port(uport); + /* + * If we failed to restore the old settings, + * we fail like this. + */ + if (retval) + uport->type = PORT_UNKNOWN; + + /* + * We failed anyway. + */ + retval = -EBUSY; + } + /* Added to return the correct error -Ram Gupta */ goto exit; } @@ -1571,12 +1580,6 @@ static int uart_open(struct tty_struct *tty, struct file *filp) } /* - * Make sure the device is in D0 state. - */ - if (port->count == 1) - uart_change_pm(state, UART_PM_STATE_ON); - - /* * Start up the serial port. */ retval = uart_startup(tty, state, 0); diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index 8ebd9f88a6f6..f1d30f6945af 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -255,11 +255,16 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size, if (change || left < size) { /* This is the slow path - looking for new buffers to use */ if ((n = tty_buffer_alloc(port, size)) != NULL) { + unsigned long iflags; + n->flags = flags; buf->tail = n; + + spin_lock_irqsave(&buf->flush_lock, iflags); b->commit = b->used; - smp_mb(); b->next = n; + spin_unlock_irqrestore(&buf->flush_lock, iflags); + } else if (change) size = 0; else @@ -443,6 +448,7 @@ static void flush_to_ldisc(struct work_struct *work) mutex_lock(&buf->lock); while (1) { + unsigned long flags; struct tty_buffer *head = buf->head; int count; @@ -450,14 +456,19 @@ static void flush_to_ldisc(struct work_struct *work) if (atomic_read(&buf->priority)) break; + spin_lock_irqsave(&buf->flush_lock, flags); count = head->commit - head->read; if (!count) { - if (head->next == NULL) + if (head->next == NULL) { + spin_unlock_irqrestore(&buf->flush_lock, flags); break; + } buf->head = head->next; + spin_unlock_irqrestore(&buf->flush_lock, flags); tty_buffer_free(port, head); continue; } + spin_unlock_irqrestore(&buf->flush_lock, flags); count = receive_buf(tty, head, count); if (!count) @@ -512,6 +523,7 @@ void tty_buffer_init(struct tty_port *port) struct tty_bufhead *buf = &port->buf; mutex_init(&buf->lock); + spin_lock_init(&buf->flush_lock); tty_buffer_reset(&buf->sentinel, 0); buf->head = &buf->sentinel; buf->tail = &buf->sentinel; |