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

Jaehoon Chung
2013-08-09T08:53:37Z

On 08/09/2013 05:30 PM, Barry Song wrote:
> 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.
Haijun, you refer to kernel/time.c

Best Regards,
Jaehoon Chung
>
>>
>>>
>>>> host->cmd = cmd;
>>>>
>>>> --
>>>> 1.8.0
>>>>
>>> -barry
>>>
>>
>>
>> --
>> Thanks & Regards
>>
>> Haijun
>>
>>
> -barry
> --
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