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 <c...@laptop.org> Signed-off-by: Girish K S <girish.shivananja...@linaro.org> --- drivers/mmc/core/mmc.c | 27 +++++++++++++++++++++++++++ include/linux/mmc/card.h | 4 ++++ 2 files changed, 31 insertions(+), 0 deletions(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 006e932..30d1cbc 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -688,6 +688,33 @@ 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 (card->host->caps & MMC_CAP_MAX_CURRENT_800) { + 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 if (card->host->caps & MMC_CAP_MAX_CURRENT_600) { + 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 if (card->host->caps & MMC_CAP_MAX_CURRENT_400) { + 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 if (card->host->caps & MMC_CAP_MAX_CURRENT_200) { + if (pwrclass_val >= MMC_MAX_CURRENT_200) + pwrclass_val = MMC_MAX_CURRENT_200; + } else + 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html