| Message ID | 1310567787-14697-1-git-send-email-balajitk@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Balaji, Tried this patch along with disabling the eMMC VCC supply in suspend and it works !!! Without this patch, if I disabled the VCC supply then after resume I/O errors are seen. This change also complies with eMMC spec so am ok with this change. Regards, Subhash
On Wed, Jul 13, 2011 at 8:06 PM, Balaji T K <balajitk@ti.com> wrote: > Put MMC to sleep if it supports SLEEP/AWAKE (CMD5) > in the mmc suspend to minimize power consumption. > > Signed-off-by: Balaji T K <balajitk@ti.com> > --- > drivers/mmc/core/mmc.c | 8 ++++++-- > 1 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index afabdc3..e8dfcde 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -900,16 +900,20 @@ static void mmc_detect(struct mmc_host *host) > */ > static int mmc_suspend(struct mmc_host *host) > { > + int err = 0; > + > BUG_ON(!host); > BUG_ON(!host->card); > > mmc_claim_host(host); > - if (!mmc_host_is_spi(host)) > + if (mmc_card_can_sleep(host)) > + err = mmc_card_sleep(host); > + else if (!mmc_host_is_spi(host)) > mmc_deselect_cards(host); > host->card->state &= ~MMC_STATE_HIGHSPEED; > mmc_release_host(host); > > - return 0; > + return err; > } > > /* > -- > 1.7.0.4 > Balaji, Would you mind reposting the patch without the RFC and s/CORE/core in subject line ? You can add my Acked-by: Venkatraman S <svenkatr@ti.com> -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On Tue, Jul 19 2011, S, Venkatraman wrote: > On Wed, Jul 13, 2011 at 8:06 PM, Balaji T K <balajitk@ti.com> wrote: >> Put MMC to sleep if it supports SLEEP/AWAKE (CMD5) >> in the mmc suspend to minimize power consumption. >> >> Signed-off-by: Balaji T K <balajitk@ti.com> > > Balaji, > Would you mind reposting the patch without the RFC and s/CORE/core > in subject line ? > You can add my > Acked-by: Venkatraman S <svenkatr@ti.com> No need to resend, thanks -- pushed to mmc-next with these changes and the ACK. Anyone object to letting this soak in mmc-next for a release and merging it in 3.2? I'm worried that we'll find card or host quirks around this, and the 3.0 release is probably happening today. - Chris.
On 19/07/2011 7:48 p.m., Chris Ball wrote: > Hi, > > On Tue, Jul 19 2011, S, Venkatraman wrote: >> On Wed, Jul 13, 2011 at 8:06 PM, Balaji T K<balajitk@ti.com> wrote: >>> Put MMC to sleep if it supports SLEEP/AWAKE (CMD5) >>> in the mmc suspend to minimize power consumption. >>> >>> Signed-off-by: Balaji T K<balajitk@ti.com> >> Balaji, >> Would you mind reposting the patch without the RFC and s/CORE/core >> in subject line ? >> You can add my >> Acked-by: Venkatraman S<svenkatr@ti.com> > No need to resend, thanks -- pushed to mmc-next with these changes and > the ACK. > > Anyone object to letting this soak in mmc-next for a release and merging > it in 3.2? I'm worried that we'll find card or host quirks around this, > and the 3.0 release is probably happening today. eMMC often have VccQ (logic) always on (or sharing the same power as SDRAM which comes to the same thing), but can switch off Vcc (NAND core). However, turning off Vcc without first putting the card to sleep can result in errors i.e. you are not allowed to do it. This patch seems to be covering the "VccQ always on" case but relies on CMD0 to wake up the card. If that is what is going on, then some comments to that effect are needed, including within mmc_init_card to note that mmc_go_idle is needed for cards that are asleep - if that is, in fact, correct. Also, wouldn't it be nice to wake up the card with CMD5 which should be much faster than re-initialising? > - Chris. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index afabdc3..e8dfcde 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -900,16 +900,20 @@ static void mmc_detect(struct mmc_host *host) */ static int mmc_suspend(struct mmc_host *host) { + int err = 0; + BUG_ON(!host); BUG_ON(!host->card); mmc_claim_host(host); - if (!mmc_host_is_spi(host)) + if (mmc_card_can_sleep(host)) + err = mmc_card_sleep(host); + else if (!mmc_host_is_spi(host)) mmc_deselect_cards(host); host->card->state &= ~MMC_STATE_HIGHSPEED; mmc_release_host(host); - return 0; + return err; } /*
Put MMC to sleep if it supports SLEEP/AWAKE (CMD5) in the mmc suspend to minimize power consumption. Signed-off-by: Balaji T K <balajitk@ti.com> --- drivers/mmc/core/mmc.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-)