On 23 January 2014 11:09, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote: > On 22/01/14 17:00, Ulf Hansson wrote: >> Hosts supporting MMC_CAP_WAIT_WHILE_BUSY shall not be waiting for busy >> detection completion in the recovery path, which were the case when >> using R1B response. >> >> Start using R1 as response instead to align behavior, no matter if >> MMC_CAP_WAIT_WHILE_BUSY is supported or not. > > This does not make sense to me. If you are sending a STOP command you > should use the correct response type. R1B should be OK here because the > card should release the busy signal in any case except failure. For those hosts not supporting MMC_CAP_WAIT_WHILE_BUSY a R1B is assumed to be treated same as an R1, which means there are no busy detection handled in the host. mmc_blk_cmd_recovery() is the only caller of the send_stop() function. Additionally it does not care about to handle busy detection with CDM13 polling. Now, since most hosts don't support MMC_CAP_WAIT_WHILE_BUSY which means there no busy detection done, I wanted to align to this behaviour - no matter if the host can do HW busy detection or not. I am not saying this is how it must be done, just trying to provide you with some more reasons to why I wanted to change. If we instead decide keep the R1B for send_stop(), we should implement CMD 13 polling to meet the same behaviour for hosts not supporting MMC_CAP_WAIT_WHILE_BUSY. In this scenario, we need to set a select a busy timeout, do you have any suggestion of what would be a reasonable value for it? Kind regards Ulf Hansson > >> >> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> >> --- >> drivers/mmc/card/block.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >> index 87cd2b0..74169fa 100644 >> --- a/drivers/mmc/card/block.c >> +++ b/drivers/mmc/card/block.c >> @@ -728,7 +728,7 @@ static int send_stop(struct mmc_card *card, u32 *status) >> int err; >> >> cmd.opcode = MMC_STOP_TRANSMISSION; >> - cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; >> + cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC; >> err = mmc_wait_for_cmd(card->host, &cmd, 5); >> if (err == 0) >> *status = cmd.resp[0]; >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
