Put MMC to sleep if it supports SLEEP/AWAKE (CMD5) in the mmc suspend so that Vcc (NAND core) can be cut to minimize power consumption. eMMC put into SLEEP can respond to CMD0 or H/W reset or CMD5. Current implemention on resume from suspend relies on CMD0 in mmc_init_card to get out of SLEEP mode.
Signed-off-by: Balaji T K <[email protected]> Acked-by: Venkatraman S <[email protected]> --- drivers/mmc/core/mmc.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 5700b1c..f73fcee 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -553,6 +553,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, * need to tell some cards to go back to the idle * state. We wait 1ms to give cards time to * respond. + * mmc_go_idle is needed for eMMC that are asleep */ mmc_go_idle(host); @@ -900,16 +901,20 @@ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
