Fwd: Re: mmc: core: retries counter for data command initialization.

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Hello Chris, Ulf,

Sorry for nagging.

Do you have opinion on issue with retries counter for data command?

Since till now the code behave as there is no retry, may be it is better to remove dead code? Or the counter need to be initialized properly.

On 04/29/14 10:55, Konstantin Dorfman wrote:

Hi All,

After 6035d9730d5825e6e3c225b721a5847a521d6556 "mmc: fix async request
mechanism for sequential read scenarios" mmc layer data path async
request handling was separated from mmc commands path.

mmc_wait_for_data_req_done() function is used to wait for completion of
the currently running data request, while for commands
mmc_wait_for_req_done() is used.

There is code that repeats request cmd->retries times in case of error.
The problem that for data command this counter is not initialized
properly as it does for mmc command sending:


int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int
retries)
{
     struct mmc_request mrq = {NULL};

     WARN_ON(!host->claimed);

     memset(cmd->resp, 0, sizeof(cmd->resp));
     cmd->retries = retries;                 <-- supplied by
                                                     caller

     mrq.cmd = cmd;
     cmd->data = NULL;

     mmc_wait_for_req(host, &mrq);

     return cmd->error;
}

I found that there is no similar initialization for data command
processing code, so the counter cmd->retries remains always 0.

Lets discuss:
- do we need retries for data request
- what value is good: for command there are 0 or 5 retries
- where to do this initialization:

card/block.c: static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
			       struct mmc_card *card,
			       int disable_multi,
			       struct mmc_queue *mq)

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