> -----Original Message----- > From: Girish K S [mailto:girish.shivananjappa@xxxxxxxxxx] > Sent: Wednesday, December 14, 2011 5:31 PM > To: linux-mmc@xxxxxxxxxxxxxxx > Cc: patches@xxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; > subhashj@xxxxxxxxxxxxxx; Girish K S; Chris Ball > Subject: [PATCH V1] mmc: core: Add host capability check for power > class > > This patch adds a check whether the host supports maximum current value > obtained from the device's extended csd register for a selected > interface > voltage and frequency. > > cc: Chris Ball <cjb@xxxxxxxxxx> > Signed-off-by: Girish K S <girish.shivananjappa@xxxxxxxxxx> > --- > Changes in v1: > reduced the number of comparisons as per Hein's suggestion > > drivers/mmc/core/mmc.c | 21 +++++++++++++++++++++ > include/linux/mmc/card.h | 4 ++++ > 2 files changed, 25 insertions(+), 0 deletions(-) > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index 006e932..e7f1902 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -688,6 +688,27 @@ static int mmc_select_powerclass(struct mmc_card > *card, > pwrclass_val = (pwrclass_val & EXT_CSD_PWR_CL_4BIT_MASK) >> > EXT_CSD_PWR_CL_4BIT_SHIFT; > > + if (pwrclass_val >= MMC_MAX_CURRENT_800) > + pwrclass_val = MMC_MAX_CURRENT_800; > + else if (pwrclass_val >= MMC_MAX_CURRENT_600) > + pwrclass_val = MMC_MAX_CURRENT_600; > + else if (pwrclass_val >= MMC_MAX_CURRENT_400) > + pwrclass_val = MMC_MAX_CURRENT_400; > + else if (pwrclass_val >= MMC_MAX_CURRENT_200) > + pwrclass_val = MMC_MAX_CURRENT_200; > + else > + pwrclass_val = MMC_MAX_CURRENT_200; Last else if and else can be combined as they are assigning the same value to pwrclass_val. > + > + if ((pwrclass_val == MMC_MAX_CURRENT_800) && > + !(card->host->caps & MMC_CAP_MAX_CURRENT_800)) > + pwrclass_val = MMC_MAX_CURRENT_600; > + if ((pwrclass_val == MMC_MAX_CURRENT_600) && > + !(card->host->caps & MMC_CAP_MAX_CURRENT_600)) > + pwrclass_val = MMC_MAX_CURRENT_400; > + if ((pwrclass_val == MMC_MAX_CURRENT_400) && > + !(card->host->caps & MMC_CAP_MAX_CURRENT_400)) > + pwrclass_val = MMC_MAX_CURRENT_200; > + > /* If the power class is different from the default value */ > if (pwrclass_val > 0) { > err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h > index 9478a6b..c5e031a 100644 > --- a/include/linux/mmc/card.h > +++ b/include/linux/mmc/card.h > @@ -195,6 +195,10 @@ struct mmc_part { > #define MMC_BLK_DATA_AREA_GP (1<<2) > }; > > +#define MMC_MAX_CURRENT_200 (0) > +#define MMC_MAX_CURRENT_400 (7) > +#define MMC_MAX_CURRENT_600 (11) > +#define MMC_MAX_CURRENT_800 (13) > /* > * MMC device > */ > -- > 1.7.1 -- 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
