Commit f338529c authored by Sarthak Garg's avatar Sarthak Garg Committed by Ulf Hansson
Browse files

mmc: core: Parse and use the new max-sd-hs-hz DT property 



Introduce a new device tree flag to cap the maximum High-Speed (HS)
mode frequency for SD cards, accommodating board-specific
electrical limitations which cannot support the default 50Mhz HS
frequency and others.

Signed-off-by: default avatarSarthak Garg <quic_sartgarg@quicinc.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 98682689

drivers/mmc/core/host.c

+2 −0
Original line number Diff line number Diff line
@@ -302,6 +302,8 @@ int mmc_of_parse(struct mmc_host *host) 
	/* f_max is obtained from the optional "max-frequency" property */

	device_property_read_u32(dev, "max-frequency", &host->f_max);



	device_property_read_u32(dev, "max-sd-hs-hz", &host->max_sd_hs_hz);



	/*

	 * Configure CD and WP pins. They are both by default active low to

	 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the

drivers/mmc/core/sd.c

+1 −1
Original line number Diff line number Diff line
@@ -359,7 +359,7 @@ static int mmc_read_switch(struct mmc_card *card) 
	}



	if (status[13] & SD_MODE_HIGH_SPEED)

		card->sw_caps.hs_max_dtr = HIGH_SPEED_MAX_DTR;

		card->sw_caps.hs_max_dtr = card->host->max_sd_hs_hz ?: HIGH_SPEED_MAX_DTR;



	if (card->scr.sda_spec3) {

		card->sw_caps.sd3_bus_mode = status[13];

include/linux/mmc/host.h

+1 −0
Original line number Diff line number Diff line
@@ -576,6 +576,7 @@ struct mmc_host { 
	int			hsq_depth;



	u32			err_stats[MMC_ERR_MAX];

	u32			max_sd_hs_hz;

	unsigned long		private[] ____cacheline_aligned;

};