mmc: sdio: Don't re-initialize powered-on removable SDIO cards at resume (6ebc581c) · Commits · 戴 / test

It looks like the original idea behind always doing a re-initialization of a removable SDIO card during system resume in mmc_sdio_resume(), is to try to play safe to detect whether the card has been removed. However, this seems like a really a bad idea as it will most likely screw things up, especially when the card is expected to remain powered on during system suspend by the SDIO func driver. Let's fix this, simply by trusting that the detect work checks if the card is alive and inserted, which is being scheduled at the PM_POST_SUSPEND notification anyway. Signed-off-by:

Ulf Hansson <ulf.hansson@linaro.org> Tested-by:

Douglas Anderson <dianders@chromium.org> Reviewed-by:

Douglas Anderson <dianders@chromium.org>

drivers/mmc/core/sdio.c

+7 −7

Original line number	Diff line number	Diff line
		@@ -982,7 +982,11 @@ static int mmc_sdio_resume(struct mmc_host *host)
		/* Basic card reinitialization. */
		mmc_claim_host(host);

		/* Restore power if needed */
		/*
		* Restore power and reinitialize the card when needed. Note that a
		* removable card is checked from a detect work later on in the resume
		* process.
		*/
		if (!mmc_card_keep_power(host)) {
		mmc_power_up(host, host->card->ocr);
		/*
		@@ -996,12 +1000,8 @@ static int mmc_sdio_resume(struct mmc_host *host)
		pm_runtime_set_active(&host->card->dev);
		pm_runtime_enable(&host->card->dev);
		}
		}

		/* No need to reinitialize powered-resumed nonremovable cards */
		if (mmc_card_is_removable(host) \|\| !mmc_card_keep_power(host)) {
		err = mmc_sdio_reinit_card(host, mmc_card_keep_power(host));
		} else if (mmc_card_keep_power(host) && mmc_card_wake_sdio_irq(host)) {
		err = mmc_sdio_reinit_card(host, 0);
		} else if (mmc_card_wake_sdio_irq(host)) {
		/* We may have switched to 1-bit mode during suspend */
		err = sdio_enable_4bit_bus(host->card);
		}

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