Commit f9996aee authored by Pierre Ossman's avatar Pierre Ossman
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mmc: increase power up delay 



Increase delay for power up in order to support some slower boards.

Also add some comments about why the delays are there.

Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent f75979b7

drivers/mmc/core/core.c

+9 −1
Original line number Diff line number Diff line
@@ -460,12 +460,20 @@ static void mmc_power_up(struct mmc_host *host) 
	host->ios.timing = MMC_TIMING_LEGACY;

	mmc_set_ios(host);



	mmc_delay(1);

	/*

	 * This delay should be sufficient to allow the power supply

	 * to reach the minimum voltage.

	 */

	mmc_delay(2);



	host->ios.clock = host->f_min;

	host->ios.power_mode = MMC_POWER_ON;

	mmc_set_ios(host);



	/*

	 * This delay must be at least 74 clock sizes, or 1 ms, or the

	 * time required to reach a stable voltage.

	 */

	mmc_delay(2);

}