[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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