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authorZiqi Chen <ziqichen@codeaurora.org>2021-01-08 18:56:25 +0800
committerMartin K. Petersen <martin.petersen@oracle.com>2021-01-12 23:37:34 -0500
commitb61d0414136853fc38898829cde837ce5d691a9a (patch)
tree6fe403b521fe13266b81664315a6f2f9e608d24e
parent528db9e563d1cb6abf60417ea0bedbd492c68ee4 (diff)
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: Avri Altman <avri.altman@wdc.com> Signed-off-by: Ziqi Chen <ziqichen@codeaurora.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
-rw-r--r--drivers/scsi/ufs/ufs-qcom.c18
1 files changed, 16 insertions, 2 deletions
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 2206b1e4b774..f97d7b0ae3b6 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -568,6 +568,17 @@ out:
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;