scsi: ufs: Allow an error return value from ->device_reset()

[ Upstream commit 151f1b664ffbb847c7fbbce5a5b8580f1b9b1d98 ]

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.

Link: https://lore.kernel.org/r/20201103141403.2142-3-adrian.hunter@intel.com
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean huo <beanhuo@micron.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
index 8df73bc..914a827 100644 (file)
--- 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 f9d6ef3..a244c8a 100644 (file)
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1421,13 +1421,13 @@ 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
@@ -1438,6 +1438,8 @@ 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 e0f00a4..de97971 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -318,7 +318,7 @@ 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);
@@ -1181,9 +1181,12 @@ 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);
        }
 }