[PATCH] serial: omap: fix the overrun case
shubhrajyoti at ti.com
Fri Sep 21 07:16:52 EDT 2012
On Friday 21 September 2012 04:30 PM, Felipe Balbi wrote:
> On Fri, Sep 21, 2012 at 03:52:56PM +0530, Shubhrajyoti D wrote:
>> Overrun also causes an internal flag to be set, which disables further
>> reception. Before the next frame can
>> be received, the MPU must:
>> • Reset the RX FIFO.
>> • clear the internal flag.
>> In the uart mode a dummy read is needed. Add the same.
> Very nice patch but I think commit log can be a bit more verbose.
> Please make the problem a little clearer. Why do we even get that
> interrupt fired if BRK_ERROR_BITS aren't set ?
I did not get this point.
it it is ! BRK_ERROR_BITS I return.
If it is and there is data in the fifo then a read is done.
>> Signed-off-by: Shubhrajyoti D <shubhrajyoti at ti.com>
>> - functional testing on omap4sdp
>> - Verified idle and suspend path hits off on beagle.
>> drivers/tty/serial/omap-serial.c | 7 +++++++
>> 1 files changed, 7 insertions(+), 0 deletions(-)
>> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
>> index a0d4460..bc22a2b 100644
>> --- a/drivers/tty/serial/omap-serial.c
>> +++ b/drivers/tty/serial/omap-serial.c
>> @@ -334,6 +334,13 @@ static unsigned int check_modem_status(struct uart_omap_port *up)
>> static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
>> unsigned int flag;
>> + unsigned char ch = 0;
>> + if (!(lsr & UART_LSR_BRK_ERROR_BITS))
>> + return;
>> + if (likely(lsr & UART_LSR_DR))
>> + ch = serial_in(up, UART_RX);
> Maybe add a comment before this condition stating why this character
> read is necessary ?
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