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>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index b0f791a..fb1234e 100644 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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);
 }
 
 /**