Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
+56
-34
+1
-1
drivers/tty/serial/8250/8250_core.c
+1
-1
drivers/tty/serial/8250/8250_core.c
+7
-2
drivers/tty/serial/8250/8250_dma.c
+7
-2
drivers/tty/serial/8250/8250_dma.c
···
20
20
struct uart_8250_port *p = param;
21
21
struct uart_8250_dma *dma = p->dma;
22
22
struct circ_buf *xmit = &p->port.state->xmit;
23
-
24
-
dma->tx_running = 0;
23
+
unsigned long flags;
25
24
26
25
dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr,
27
26
UART_XMIT_SIZE, DMA_TO_DEVICE);
27
+
28
+
spin_lock_irqsave(&p->port.lock, flags);
29
+
30
+
dma->tx_running = 0;
28
31
29
32
xmit->tail += dma->tx_size;
30
33
xmit->tail &= UART_XMIT_SIZE - 1;
···
38
35
39
36
if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port))
40
37
serial8250_tx_dma(p);
38
+
39
+
spin_unlock_irqrestore(&p->port.lock, flags);
41
40
}
42
41
43
42
static void __dma_rx_complete(void *param)
+12
-11
drivers/tty/serial/samsung.c
+12
-11
drivers/tty/serial/samsung.c
···
1446
1446
static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1447
1447
unsigned char c)
1448
1448
{
1449
-
unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
1450
-
unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
1449
+
unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
1450
+
unsigned int ucon = rd_regl(port, S3C2410_UCON);
1451
1451
1452
1452
/* not possible to xmit on unconfigured port */
1453
1453
if (!s3c24xx_port_configured(ucon))
···
1455
1455
1456
1456
while (!s3c24xx_serial_console_txrdy(port, ufcon))
1457
1457
cpu_relax();
1458
-
wr_regb(cons_uart, S3C2410_UTXH, c);
1458
+
wr_regb(port, S3C2410_UTXH, c);
1459
1459
}
1460
1460
1461
1461
#endif /* CONFIG_CONSOLE_POLL */
···
1463
1463
static void
1464
1464
s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
1465
1465
{
1466
-
unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
1467
-
unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
1468
-
1469
-
/* not possible to xmit on unconfigured port */
1470
-
if (!s3c24xx_port_configured(ucon))
1471
-
return;
1466
+
unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
1472
1467
1473
1468
while (!s3c24xx_serial_console_txrdy(port, ufcon))
1474
-
barrier();
1475
-
wr_regb(cons_uart, S3C2410_UTXH, ch);
1469
+
cpu_relax();
1470
+
wr_regb(port, S3C2410_UTXH, ch);
1476
1471
}
1477
1472
1478
1473
static void
1479
1474
s3c24xx_serial_console_write(struct console *co, const char *s,
1480
1475
unsigned int count)
1481
1476
{
1477
+
unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
1478
+
1479
+
/* not possible to xmit on unconfigured port */
1480
+
if (!s3c24xx_port_configured(ucon))
1481
+
return;
1482
+
1482
1483
uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
1483
1484
}
1484
1485
+21
-18
drivers/tty/serial/serial_core.c
+21
-18
drivers/tty/serial/serial_core.c
···
137
137
return 1;
138
138
139
139
/*
140
+
* Make sure the device is in D0 state.
141
+
*/
142
+
uart_change_pm(state, UART_PM_STATE_ON);
143
+
144
+
/*
140
145
* Initialise and allocate the transmit and temporary
141
146
* buffer.
142
147
*/
···
830
825
* If we fail to request resources for the
831
826
* new port, try to restore the old settings.
832
827
*/
833
-
if (retval && old_type != PORT_UNKNOWN) {
828
+
if (retval) {
834
829
uport->iobase = old_iobase;
835
830
uport->type = old_type;
836
831
uport->hub6 = old_hub6;
837
832
uport->iotype = old_iotype;
838
833
uport->regshift = old_shift;
839
834
uport->mapbase = old_mapbase;
840
-
retval = uport->ops->request_port(uport);
841
-
/*
842
-
* If we failed to restore the old settings,
843
-
* we fail like this.
844
-
*/
845
-
if (retval)
846
-
uport->type = PORT_UNKNOWN;
847
835
848
-
/*
849
-
* We failed anyway.
850
-
*/
851
-
retval = -EBUSY;
836
+
if (old_type != PORT_UNKNOWN) {
837
+
retval = uport->ops->request_port(uport);
838
+
/*
839
+
* If we failed to restore the old settings,
840
+
* we fail like this.
841
+
*/
842
+
if (retval)
843
+
uport->type = PORT_UNKNOWN;
844
+
845
+
/*
846
+
* We failed anyway.
847
+
*/
848
+
retval = -EBUSY;
849
+
}
850
+
852
851
/* Added to return the correct error -Ram Gupta */
853
852
goto exit;
854
853
}
···
1578
1569
retval = -EAGAIN;
1579
1570
goto err_dec_count;
1580
1571
}
1581
-
1582
-
/*
1583
-
* Make sure the device is in D0 state.
1584
-
*/
1585
-
if (port->count == 1)
1586
-
uart_change_pm(state, UART_PM_STATE_ON);
1587
1572
1588
1573
/*
1589
1574
* Start up the serial port.
+14
-2
drivers/tty/tty_buffer.c
+14
-2
drivers/tty/tty_buffer.c
···
255
255
if (change || left < size) {
256
256
/* This is the slow path - looking for new buffers to use */
257
257
if ((n = tty_buffer_alloc(port, size)) != NULL) {
258
+
unsigned long iflags;
259
+
258
260
n->flags = flags;
259
261
buf->tail = n;
262
+
263
+
spin_lock_irqsave(&buf->flush_lock, iflags);
260
264
b->commit = b->used;
261
-
smp_mb();
262
265
b->next = n;
266
+
spin_unlock_irqrestore(&buf->flush_lock, iflags);
267
+
263
268
} else if (change)
264
269
size = 0;
265
270
else
···
448
443
mutex_lock(&buf->lock);
449
444
450
445
while (1) {
446
+
unsigned long flags;
451
447
struct tty_buffer *head = buf->head;
452
448
int count;
453
449
···
456
450
if (atomic_read(&buf->priority))
457
451
break;
458
452
453
+
spin_lock_irqsave(&buf->flush_lock, flags);
459
454
count = head->commit - head->read;
460
455
if (!count) {
461
-
if (head->next == NULL)
456
+
if (head->next == NULL) {
457
+
spin_unlock_irqrestore(&buf->flush_lock, flags);
462
458
break;
459
+
}
463
460
buf->head = head->next;
461
+
spin_unlock_irqrestore(&buf->flush_lock, flags);
464
462
tty_buffer_free(port, head);
465
463
continue;
466
464
}
465
+
spin_unlock_irqrestore(&buf->flush_lock, flags);
467
466
468
467
count = receive_buf(tty, head, count);
469
468
if (!count)
···
523
512
struct tty_bufhead *buf = &port->buf;
524
513
525
514
mutex_init(&buf->lock);
515
+
spin_lock_init(&buf->flush_lock);
526
516
tty_buffer_reset(&buf->sentinel, 0);
527
517
buf->head = &buf->sentinel;
528
518
buf->tail = &buf->sentinel;