Re: [PATCH V4 2/2] scsi: ufs: Allow an error return value from ->device_reset()

From: Asutosh Das (asd)
Date: Wed Nov 04 2020 - 11:35:06 EST


On 11/3/2020 6:14 AM, Adrian Hunter wrote:
It is simpler for drivers to provide a ->device_reset() callback
irrespective of whether the GPIO, or firmware interface necessary to do the
reset, is discovered during probe.

Change ->device_reset() to return an error code. Drivers that provide
the callback, but do not do the reset operation should return -EOPNOTSUPP.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

Reviewed-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>

---
drivers/scsi/ufs/ufs-mediatek.c | 4 +++-
drivers/scsi/ufs/ufs-qcom.c | 6 ++++--
drivers/scsi/ufs/ufshcd.h | 11 +++++++----
3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
index 8df73bc2f8cb..914a827a93ee 100644
--- a/drivers/scsi/ufs/ufs-mediatek.c
+++ b/drivers/scsi/ufs/ufs-mediatek.c
@@ -743,7 +743,7 @@ static int ufs_mtk_link_startup_notify(struct ufs_hba *hba,
return ret;
}
-static void ufs_mtk_device_reset(struct ufs_hba *hba)
+static int ufs_mtk_device_reset(struct ufs_hba *hba)
{
struct arm_smccc_res res;
@@ -764,6 +764,8 @@ static void ufs_mtk_device_reset(struct ufs_hba *hba)
usleep_range(10000, 15000);
dev_info(hba->dev, "device reset done\n");
+
+ return 0;
}
static int ufs_mtk_link_set_hpm(struct ufs_hba *hba)
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 9a19c6d15d3b..357c3b49321d 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1422,13 +1422,13 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
*
* Toggles the (optional) reset line to reset the attached device.
*/
-static void ufs_qcom_device_reset(struct ufs_hba *hba)
+static int ufs_qcom_device_reset(struct ufs_hba *hba)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
/* reset gpio is optional */
if (!host->device_reset)
- return;
+ return -EOPNOTSUPP;
/*
* The UFS device shall detect reset pulses of 1us, sleep for 10us to
@@ -1439,6 +1439,8 @@ static void ufs_qcom_device_reset(struct ufs_hba *hba)
gpiod_set_value_cansleep(host->device_reset, 0);
usleep_range(10, 15);
+
+ return 0;
}
#if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 213be0667b59..5191d87f6263 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -323,7 +323,7 @@ struct ufs_hba_variant_ops {
int (*resume)(struct ufs_hba *, enum ufs_pm_op);
void (*dbg_register_dump)(struct ufs_hba *hba);
int (*phy_initialization)(struct ufs_hba *);
- void (*device_reset)(struct ufs_hba *hba);
+ int (*device_reset)(struct ufs_hba *hba);
void (*config_scaling_param)(struct ufs_hba *hba,
struct devfreq_dev_profile *profile,
void *data);
@@ -1207,9 +1207,12 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
{
if (hba->vops && hba->vops->device_reset) {
- hba->vops->device_reset(hba);
- ufshcd_set_ufs_dev_active(hba);
- ufshcd_update_reg_hist(&hba->ufs_stats.dev_reset, 0);
+ int err = hba->vops->device_reset(hba);
+
+ if (!err)
+ ufshcd_set_ufs_dev_active(hba);
+ if (err != -EOPNOTSUPP)
+ ufshcd_update_reg_hist(&hba->ufs_stats.dev_reset, err);
}
}



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