> -----Original Message----- > From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] > Sent: Friday, January 13, 2017 7:05 PM > To: linux-mmc@xxxxxxxxxxxxxxx; Ulf Hansson <ulf.hansson@xxxxxxxxxx> > Cc: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>; Adrian Hunter > <adrian.hunter@xxxxxxxxx>; Linus Walleij <linus.walleij@xxxxxxxxxx>; Chaotian > Jing <chaotian.jing@xxxxxxxxxxxx>; Yong Mao <yong.mao@xxxxxxxxxxxx>; > Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>; Clemens Gruber > <clemens.gruber@xxxxxxxxxxxx>; Gary Bisson > <gary.bisson@xxxxxxxxxxxxxxxxxxx>; Dong Aisheng <dongas86@xxxxxxxxx>; > Fabio Estevam <festevam@xxxxxxxxx>; A.S. Dong <aisheng.dong@xxxxxxx>; > Bough Chen <haibo.chen@xxxxxxx> > Subject: [PATCH] mmc: core: Restore parts of the polling policy when switch to > HS/HS DDR > > Regressions for not being able to detect an eMMC HS DDR mode card has been > reported for the sdhci-esdhc-imx driver, but potentially other sdhci variants > may suffer from the similar problem. > > The commit e173f8911f09 ("mmc: core: Update CMD13 polling policy when > switch to HS DDR mode"), is causing the problem. It seems that change moved > one step to far, regarding changing the host's timing before polling for a busy > card. > > To fix this, let's move back to the behaviour when the host's timing is updated > after the polling, but before the switch status is fetched and validated. > > In cases when polling with CMD13, we keep validating the switch status at each > attempt. However, to align with the other card busy detections mechanism, > let's fetch and validate the switch status also after the host's timing is updated. > > Reported-by: Clemens Gruber <clemens.gruber@xxxxxxxxxxxx> > Reported-by: Gary Bisson <gary.bisson@xxxxxxxxxxxxxxxxxxx> > Fixes: e173f8911f09 ("mmc: core: Update CMD13 polling policy when switch..") > Cc: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> > Cc: Dong Aisheng <aisheng.dong@xxxxxxx> > Cc: Haibo Chen <haibo.chen@xxxxxxx> > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > --- > drivers/mmc/core/mmc_ops.c | 25 ++++++++++++------------- > 1 file changed, 12 insertions(+), 13 deletions(-) > > diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c > index db2969f..fe80f26 100644 > --- a/drivers/mmc/core/mmc_ops.c > +++ b/drivers/mmc/core/mmc_ops.c > @@ -506,9 +506,6 @@ static int mmc_poll_for_busy(struct mmc_card *card, > unsigned int timeout_ms, > } > } while (busy); > > - if (host->ops->card_busy && send_status) > - return mmc_switch_status(card); > - > return 0; > } > > @@ -577,24 +574,26 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 > index, u8 value, > if (!use_busy_signal) > goto out; > > - /* Switch to new timing before poll and check switch status. */ > - if (timing) > - mmc_set_timing(host, timing); > - > /*If SPI or used HW busy detection above, then we don't need to poll. > */ > if (((host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp) > || > - mmc_host_is_spi(host)) { > - if (send_status) > - err = mmc_switch_status(card); > + mmc_host_is_spi(host)) > goto out_tim; > - } > > /* Let's try to poll to find out when the command is completed. */ > err = mmc_poll_for_busy(card, timeout_ms, send_status, > retry_crc_err); > + if (err) > + goto out; > > out_tim: > - if (err && timing) > - mmc_set_timing(host, old_timing); > + /* Switch to new timing before check switch status. */ > + if (timing) > + mmc_set_timing(host, timing); > + > + if (send_status) { > + err = mmc_switch_status(card); > + if (err && timing) > + mmc_set_timing(host, old_timing); > + } > out: > mmc_retune_release(host); > > -- > 1.9.1 Test this patch on i.MX6Q-SABRESD board, it can fix the issue. Tested-by: Haibo Chen <haibo.chen@xxxxxxx> Best Regards, Hiabo Chen -- 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
