[PATCH 1/2] serial: mxs-auart: fix the wrong setting order
Huang Shijie
b32955 at freescale.com
Thu Sep 6 22:43:59 EDT 2012
于 2012年09月07日 10:38, Shawn Guo 写道:
> On Thu, Sep 06, 2012 at 10:38:40PM -0400, Huang Shijie wrote:
>> After set the AUART_CTRL0_CLKGATE, the UART will gate all the clocks off.
>> So the following line will not take effect.
>> ................................................................
>> writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
>> u->membase + AUART_INTR_CLR);
>> ................................................................
>>
>> To fix this issue, the patch moves this gate-off line to
>> the end of setting registers.
>>
>> Signed-off-by: Huang Shijie<shijie8 at gmail.com>
> Acked-by: Shawn Guo<shawn.guo at linaro.org>
>
> Are you experiencing any user visible problem with this bug?
>
I do not experience any user problem.
I found this bug when i tried to add DMA support for MXS-AUART.
Best Regards
Huang Shijie
> Regards,
> Shawn
>
>> ---
>> drivers/tty/serial/mxs-auart.c | 4 ++--
>> 1 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
>> index dafeef2..ea5f888 100644
>> --- a/drivers/tty/serial/mxs-auart.c
>> +++ b/drivers/tty/serial/mxs-auart.c
>> @@ -457,11 +457,11 @@ static void mxs_auart_shutdown(struct uart_port *u)
>>
>> writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
>>
>> - writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
>> -
>> writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
>> u->membase + AUART_INTR_CLR);
>>
>> + writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
>> +
>> clk_disable_unprepare(s->clk);
>> }
>>
>> --
>> 1.7.4.4
>>
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