diff options
| author | Bin Gao <bin.gao@intel.com> | 2013-10-09 10:39:17 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-16 13:08:16 -0700 |
| commit | b6951b8a63e8764558c066369a6317bfe15dca55 (patch) | |
| tree | 326d50cf4fdbee33a3205424ea5d0b236f64aa27 /drivers/tty/serial/mrst_max3110.c | |
| parent | 09238443c61e58f7fac8a3892b14b1bee40b4316 (diff) | |
serial: mrst_max3110: Fix race condition between spi transfers
There is a race between termios configuration and xmit that can cause the
intel_mid_ssp_spi driver to stall.
Serializing spi transactions fixes the problem.
Signed-off-by: Bin Gao <bin.gao@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/mrst_max3110.c')
| -rw-r--r-- | drivers/tty/serial/mrst_max3110.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c index ee77e7366ed6..565779dc7aac 100644 --- a/drivers/tty/serial/mrst_max3110.c +++ b/drivers/tty/serial/mrst_max3110.c @@ -61,6 +61,7 @@ struct uart_max3110 { struct task_struct *main_thread; struct task_struct *read_thread; struct mutex thread_mutex; + struct mutex io_mutex; u32 baud; u16 cur_conf; @@ -90,6 +91,7 @@ static int max3110_write_then_read(struct uart_max3110 *max, struct spi_transfer x; int ret; + mutex_lock(&max->io_mutex); spi_message_init(&message); memset(&x, 0, sizeof x); x.len = len; @@ -104,6 +106,7 @@ static int max3110_write_then_read(struct uart_max3110 *max, /* Do the i/o */ ret = spi_sync(spi, &message); + mutex_unlock(&max->io_mutex); return ret; } @@ -805,6 +808,7 @@ static int serial_m3110_probe(struct spi_device *spi) max->irq = (u16)spi->irq; mutex_init(&max->thread_mutex); + mutex_init(&max->io_mutex); max->word_7bits = 0; max->parity = 0; |