[PATCH V4 05/17] scsi: ufs: add voting support for host controller power

Dolev Raviv
2014-09-23T07:32:13Z

From: Raviv Shvili <rshvili@codeaurora.org>

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>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index b0f791a..fb1234e 100644
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -9,6 +9,7 @@ Required properties:
- reg : <registers mapping>

Optional properties:
+- vdd-hba-supply : phandle to UFS host controller supply regulator node
- vcc-supply : phandle to VCC supply regulator node
- vccq-supply : phandle to VCCQ supply regulator node
- vccq2-supply : phandle to VCCQ2 supply regulator node
@@ -20,6 +21,7 @@ Optional properties:
- vcc-max-microamp : specifies max. load that can be drawn from vcc supply
- vccq-max-microamp : specifies max. load that can be drawn from vccq supply
- vccq2-max-microamp : specifies max. load that can be drawn from vccq2 supply
+- <name>-fixed-regulator : boolean property specifying that <name>-supply is a fixed regulator

- clocks : List of phandle and clock specifier pairs
- clock-names : List of clock input name strings sorted in the same
@@ -39,6 +41,8 @@ Example:
reg = <0xfc598000 0x800>;
interrupts = <0 28 0>;

+ vdd-hba-supply = <&xxx_reg0>;
+ vdd-hba-fixed-regulator;
vcc-supply = <&xxx_reg1>;
vcc-supply-1p8;
vccq-supply = <&xxx_reg2>;
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 729ce7d..9bb6919 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 642d80f..dde4e6e 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 b033702..26301b8 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);