This is a note to let you know that I've just added the patch titled
scsi: ufs-qcom: Fix ufs RST_n spec violation
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-ufs-qcom-fix-ufs-rst_n-spec-violation.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7b44a4d063db329f4115083ba843eaa661557a13
Author: Ziqi Chen <ziqichen@xxxxxxxxxxxxxx>
Date: Fri Jan 8 18:56:25 2021 +0800
scsi: ufs-qcom: Fix ufs RST_n spec violation
[ Upstream commit b61d0414136853fc38898829cde837ce5d691a9a ]
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@xxxxxxxxxxxxxx
Acked-by: Avri Altman <avri.altman@xxxxxxx>
Signed-off-by: Ziqi Chen <ziqichen@xxxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Stable-dep-of: a862fafa263a ("scsi: ufs: qcom: Perform read back after writing REG_UFS_SYS1CLK_1US")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 08331ecbe91fb..a432c561c3df0 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -578,6 +578,17 @@ 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);
@@ -592,6 +603,9 @@ 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);
}
@@ -1441,10 +1455,10 @@ 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;
