Commit 4caf653a authored by Ulf Hansson's avatar Ulf Hansson
Browse files

mmc: sh_mmcif: Restructure ->set_ios() 



Both from a runtime PM and clock management point of view, the ->set_ios()
code is unnecessary complex.

A suboptimal path is also executed when the mmc core requests a clock rate
of zero. As that happens during the card initialization phase, trying to
save power by decreasing the runtime PM usage count and gating the clock
via clk_disable_unprepare() is just superfluous.

Moreover, from a runtime PM point of view the core will anyway keep the
device active during the entire card initialization phase.

Restructure the code to rely on the ios->power_mode to understand when the
runtime PM usage count needs to be increased. Let's also deal with clock
rate changes by simply applying the rate.

Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 88ac2a2c

drivers/mmc/host/sh_mmcif.c

+16 −29
Original line number Diff line number Diff line
@@ -248,7 +248,6 @@ struct sh_mmcif_host { 
	int sg_idx;

	int sg_blkidx;

	bool power;

	bool card_present;

	bool ccs_enable;		/* Command Completion Signal support */

	bool clk_ctrl2_enable;

	struct mutex thread_lock;
@@ -1091,42 +1090,30 @@ static void sh_mmcif_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 
	host->state = STATE_IOS;

	spin_unlock_irqrestore(&host->lock, flags);



	if (ios->power_mode == MMC_POWER_UP) {

		if (!host->card_present) {

			/* See if we also get DMA */

	switch (ios->power_mode) {

	case MMC_POWER_UP:

		sh_mmcif_set_power(host, ios);

		if (!host->power) {

			clk_prepare_enable(host->clk);

			pm_runtime_get_sync(dev);

			sh_mmcif_sync_reset(host);

			sh_mmcif_request_dma(host);

			host->card_present = true;

			host->power = true;

		}

		break;

	case MMC_POWER_OFF:

		sh_mmcif_set_power(host, ios);

	} else if (ios->power_mode == MMC_POWER_OFF || !ios->clock) {

		/* clock stop */

		if (host->power) {

			sh_mmcif_clock_control(host, 0);

		if (ios->power_mode == MMC_POWER_OFF) {

			if (host->card_present) {

			sh_mmcif_release_dma(host);

				host->card_present = false;

			}

		}

		if (host->power) {

			pm_runtime_put_sync(dev);

			pm_runtime_put(dev);

			clk_disable_unprepare(host->clk);

			host->power = false;

			if (ios->power_mode == MMC_POWER_OFF)

				sh_mmcif_set_power(host, ios);

		}

		host->state = STATE_IDLE;

		return;

	}



	if (ios->clock) {

		if (!host->power) {

			clk_prepare_enable(host->clk);



			pm_runtime_get_sync(dev);

			host->power = true;

			sh_mmcif_sync_reset(host);

		}

		break;

	case MMC_POWER_ON:

		sh_mmcif_clock_control(host, ios->clock);

		break;

	}



	host->timing = ios->timing;

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