[PATCH v3 1/3] scsi: ufs: Introduce vops for resetting device

Bjorn Andersson
2019-06-08T05:04:56Z

Some UFS memory devices needs their reset line toggled in order to get
them into a good state for initialization. Provide a new vops to allow
the platform driver to implement this operation.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---

Changes since v2:
- New patch, to allow moving implementation to platform driver

drivers/scsi/ufs/ufshcd.c | 6 ++++++
drivers/scsi/ufs/ufshcd.h | 8 ++++++++
2 files changed, 14 insertions(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 04d3686511c8..ee895a625456 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6191,6 +6191,9 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
int retries = MAX_HOST_RESET_RETRIES;

do {
+ /* Reset the attached device */
+ ufshcd_vops_device_reset(hba);
+
err = ufshcd_host_reset_and_restore(hba);
} while (err && --retries);

@@ -8322,6 +8325,9 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
goto exit_gating;
}

+ /* Reset the attached device */
+ ufshcd_vops_device_reset(hba);
+
/* Host controller enable */
err = ufshcd_hba_enable(hba);
if (err) {
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 994d73d03207..cd8139052ed6 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -298,6 +298,7 @@ struct ufs_pwr_mode_info {
* @resume: called during host controller PM callback
* @dbg_register_dump: used to dump controller debug information
* @phy_initialization: used to initialize phys
+ * @device_reset: called to issue a reset pulse on the UFS device
*/
struct ufs_hba_variant_ops {
const char *name;
@@ -326,6 +327,7 @@ 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 *);
};

/* clock gating state */
@@ -1045,6 +1047,12 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
hba->vops->dbg_register_dump(hba);
}

+static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
+{
+ if (hba->vops && hba->vops->device_reset)
+ hba->vops->device_reset(hba);
+}
+
extern struct ufs_pm_lvl_states ufs_pm_lvl_states[];

/*
--
2.18.0