ufs: add voting support for host controller power

Add the support for voting of the regulator powering the
host controller logic.

Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

3 files changed, 50 insertions, 2 deletions

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 729ce7d62d1e..9bb691962c47 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -385,6 +385,7 @@ struct ufs_vreg_info {
         struct ufs_vreg *vcc;
         struct ufs_vreg *vccq;
         struct ufs_vreg *vccq2;
+        struct ufs_vreg *vdd_hba;
 };
 
 #endif /* End of Header */
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 642d80fe1f80..dde4e6e3be70 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -147,6 +147,11 @@ static int ufshcd_populate_vreg(struct device *dev, const char *name,
 
         vreg->name = kstrdup(name, GFP_KERNEL);
 
+        /* if fixed regulator no need further initialization */
+        snprintf(prop_name, MAX_PROP_SIZE, "%s-fixed-regulator", name);
+        if (of_property_read_bool(np, prop_name))
+                goto out;
+
         snprintf(prop_name, MAX_PROP_SIZE, "%s-max-microamp", name);
         ret = of_property_read_u32(np, prop_name, &vreg->max_uA);
         if (ret) {
@@ -198,6 +203,10 @@ static int ufshcd_parse_regulator_info(struct ufs_hba *hba)
         struct device *dev = hba->dev;
         struct ufs_vreg_info *info = &hba->vreg_info;
 
+        err = ufshcd_populate_vreg(dev, "vdd-hba", &info->vdd_hba);
+        if (err)
+                goto out;
+
         err = ufshcd_populate_vreg(dev, "vcc", &info->vcc);
         if (err)
                 goto out;
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b03370292070..26301b8325e8 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3311,6 +3311,16 @@ out:
         return ret;
 }
 
+static int ufshcd_setup_hba_vreg(struct ufs_hba *hba, bool on)
+{
+        struct ufs_vreg_info *info = &hba->vreg_info;
+
+        if (info)
+                return ufshcd_toggle_vreg(hba->dev, info->vdd_hba, on);
+
+        return 0;
+}
+
 static int ufshcd_get_vreg(struct device *dev, struct ufs_vreg *vreg)
 {
         int ret = 0;
@@ -3350,6 +3360,16 @@ out:
         return ret;
 }
 
+static int ufshcd_init_hba_vreg(struct ufs_hba *hba)
+{
+        struct ufs_vreg_info *info = &hba->vreg_info;
+
+        if (info)
+                return ufshcd_get_vreg(hba->dev, info->vdd_hba);
+
+        return 0;
+}
+
 static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
 {
         int ret = 0;
@@ -3483,14 +3503,29 @@ static int ufshcd_hba_init(struct ufs_hba *hba)
 {
         int err;
 
-        err = ufshcd_init_clocks(hba);
+        /*
+         * Handle host controller power separately from the UFS device power
+         * rails as it will help controlling the UFS host controller power
+         * collapse easily which is different than UFS device power collapse.
+         * Also, enable the host controller power before we go ahead with rest
+         * of the initialization here.
+         */
+        err = ufshcd_init_hba_vreg(hba);
         if (err)
                 goto out;
 
-        err = ufshcd_setup_clocks(hba, true);
+        err = ufshcd_setup_hba_vreg(hba, true);
         if (err)
                 goto out;
 
+        err = ufshcd_init_clocks(hba);
+        if (err)
+                goto out_disable_hba_vreg;
+
+        err = ufshcd_setup_clocks(hba, true);
+        if (err)
+                goto out_disable_hba_vreg;
+
         err = ufshcd_init_vreg(hba);
         if (err)
                 goto out_disable_clks;
@@ -3509,6 +3544,8 @@ out_disable_vreg:
         ufshcd_setup_vreg(hba, false);
 out_disable_clks:
         ufshcd_setup_clocks(hba, false);
+out_disable_hba_vreg:
+        ufshcd_setup_hba_vreg(hba, false);
 out:
         return err;
 }
@@ -3518,6 +3555,7 @@ static void ufshcd_hba_exit(struct ufs_hba *hba)
         ufshcd_variant_hba_exit(hba);
         ufshcd_setup_vreg(hba, false);
         ufshcd_setup_clocks(hba, false);
+        ufshcd_setup_hba_vreg(hba, false);
 }
 
 /**