Commit b61d0414 authored by Ziqi Chen's avatar Ziqi Chen Committed by Martin K. Petersen
Browse files

scsi: ufs-qcom: Fix ufs RST_n spec violation 

According to the spec (JESD220E chapter 7.2), while powering off/on the ufs
device, RST_n signal should be between VSS(Ground) and VCCQ/VCCQ2.

Link: https://lore.kernel.org/r/1610103385-45755-3-git-send-email-ziqichen@codeaurora.org


Acked-by: default avatarAvri Altman <avri.altman@wdc.com>
Signed-off-by: default avatarZiqi Chen <ziqichen@codeaurora.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 528db9e5

drivers/scsi/ufs/ufs-qcom.c

+16 −2
Original line number Diff line number Diff line
@@ -568,6 +568,17 @@ static int ufs_qcom_link_startup_notify(struct ufs_hba *hba, 
	return err;

}



static void ufs_qcom_device_reset_ctrl(struct ufs_hba *hba, bool asserted)

{

	struct ufs_qcom_host *host = ufshcd_get_variant(hba);



	/* reset gpio is optional */

	if (!host->device_reset)

		return;



	gpiod_set_value_cansleep(host->device_reset, asserted);

}



static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)

{

	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
@@ -582,6 +593,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) 
		ufs_qcom_disable_lane_clks(host);

		phy_power_off(phy);



		/* reset the connected UFS device during power down */

		ufs_qcom_device_reset_ctrl(hba, true);



	} else if (!ufs_qcom_is_link_active(hba)) {

		ufs_qcom_disable_lane_clks(host);

	}
@@ -1421,10 +1435,10 @@ static int ufs_qcom_device_reset(struct ufs_hba *hba) 
	 * The UFS device shall detect reset pulses of 1us, sleep for 10us to

	 * be on the safe side.

	 */

	gpiod_set_value_cansleep(host->device_reset, 1);

	ufs_qcom_device_reset_ctrl(hba, true);

	usleep_range(10, 15);



	gpiod_set_value_cansleep(host->device_reset, 0);

	ufs_qcom_device_reset_ctrl(hba, false);

	usleep_range(10, 15);



	return 0;