Re: [PATCH V2] mmc:sdhci: Wait longer for command with busy flags

Barry Song
2013-08-09T08:30:58Z

2013/8/9 Zhang Haijun <B42677@freescale.com>:
> On 08/09/2013 02:39 PM, Barry Song wrote:
>>
>> 2013/8/9 Haijun Zhang <Haijun.Zhang@freescale.com>:
>>>
>>> When command with busy flags send and also data busy end interrupt
>>> will be generate, the command will be finished when data transfer
>>> complete or data busy state end, Sometimes this will expend more than
>>> 10*Hz time to finish this command, so we should wait longer to detect
>>> command complete timeout err.
>>>
>>> Signed-off-by: Haijun Zhang <Haijun.Zhang@freescale.com>
>>> ---
>>> changes for V2:
>>> - Correct the timer
>>>
>>> drivers/mmc/host/sdhci.c | 14 +++++++++++++-
>>> 1 file changed, 13 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>>> index a78bd4f..8888578 100644
>>> --- a/drivers/mmc/host/sdhci.c
>>> +++ b/drivers/mmc/host/sdhci.c
>>> @@ -986,6 +986,7 @@ static void sdhci_send_command(struct sdhci_host
>>> *host, struct mmc_command *cmd)
>>> int flags;
>>> u32 mask;
>>> unsigned long timeout;
>>> + u32 timer = 10;
>>>
>>> WARN_ON(host->cmd);
>>>
>>> @@ -1014,7 +1015,18 @@ static void sdhci_send_command(struct sdhci_host
>>> *host, struct mmc_command *cmd)
>>> mdelay(1);
>>> }
>>>
>>> - mod_timer(&host->timer, jiffies + 10 * HZ);
>>> + /*
>>> + * When send a commmand with busy state and also the data busy
>>> end
>>> + * interrupt can be generate, the command will be finished when
>>> date
>>> + * transfer complete or busy state end. Sometimes this will
>>> expend
>>> + * more than 10*HZ, In this case whe should wait longer to detect
>>> + * command complete timeout err.
>>> + */
>>> + if ((host->cmd->flags & MMC_RSP_BUSY) &&
>>> + !(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ))
>>> + timer = 1000;
>>> +
>>> + mod_timer(&host->timer, jiffies + timer * HZ);
>>
>> haojun, do you mean we need to wait for 1 minutes and 40 seconds for
>> timeout? it seems it is too large for a kernel.
>
> 1000 * HZ = 1000 * 1 / 250 = 4000ms, about 4s. On my platform.

no. pls note the unit is jiffy not ms.

>
>>
>>> host->cmd = cmd;
>>>
>>> --
>>> 1.8.0
>>>
>> -barry
>>
>
>
> --
> Thanks & Regards
>
> Haijun
>
>
-barry