ufs: Add freq-table-hz property for UFS device

Add freq-table-hz propery for UFS device to keep track of
<min max> frequencies supported by UFS clocks.

Signed-off-by: Sahitya Tummala <stummala@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 fb1234e0532c994800a7cfdd4dd2c5cb96cd6fdc..53579197eca2a86b1b43e0cdf0ac9ba329831693 100644 (file)
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -26,11 +26,11 @@ Optional properties:
 - clocks                : List of phandle and clock specifier pairs
 - clock-names           : List of clock input name strings sorted in the same
                           order as the clocks property.
-- max-clock-frequency-hz : List of maximum operating frequency stored in the same
-                           order as the clocks property. If this property is not
-                          defined or a value in the array is "0" then it is assumed
-                          that the frequency is set by the parent clock or a
-                          fixed rate clock source.
+- freq-table-hz                : Array of <min max> operating frequencies stored in the same
+                          order as the clocks property. If this property is not
+                         defined or a value in the array is "0" then it is assumed
+                         that the frequency is set by the parent clock or a
+                         fixed rate clock source.
 
 Note: If above properties are not defined it can be assumed that the supply
 regulators or clocks are always on.
@@ -53,5 +53,5 @@ Example:
 
                clocks = <&core 0>, <&ref 0>, <&iface 0>;
                clock-names = "core_clk", "ref_clk", "iface_clk";
-               max-clock-frequency-hz = <100000000 19200000 0>;
+               freq-table-hz = <100000000 200000000>, <0 0>, <0 0>;
        };

diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 2482bbac36811a22e5dd2799bcb4bab112f343c8..8adf067ff019344eaf0c42b97007b4abac65e79e 100644 (file)
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -63,6 +63,8 @@ static int ufshcd_parse_clock_info(struct ufs_hba *hba)
        char *name;
        u32 *clkfreq = NULL;
        struct ufs_clk_info *clki;
+       int len = 0;
+       size_t sz = 0;
 
        if (!np)
                goto out;
@@ -82,39 +84,59 @@ static int ufshcd_parse_clock_info(struct ufs_hba *hba)
        if (cnt <= 0)
                goto out;
 
-       clkfreq = kzalloc(cnt * sizeof(*clkfreq), GFP_KERNEL);
+       if (!of_get_property(np, "freq-table-hz", &len)) {
+               dev_info(dev, "freq-table-hz property not specified\n");
+               goto out;
+       }
+
+       if (len <= 0)
+               goto out;
+
+       sz = len / sizeof(*clkfreq);
+       if (sz != 2 * cnt) {
+               dev_err(dev, "%s len mismatch\n", "freq-table-hz");
+               ret = -EINVAL;
+               goto out;
+       }
+
+       clkfreq = devm_kzalloc(dev, sz * sizeof(*clkfreq),
+                       GFP_KERNEL);
        if (!clkfreq) {
+               dev_err(dev, "%s: no memory\n", "freq-table-hz");
                ret = -ENOMEM;
-               dev_err(dev, "%s: memory alloc failed\n", __func__);
                goto out;
        }
 
-       ret = of_property_read_u32_array(np,
-                       "max-clock-frequency-hz", clkfreq, cnt);
+       ret = of_property_read_u32_array(np, "freq-table-hz",
+                       clkfreq, sz);
        if (ret && (ret != -EINVAL)) {
-               dev_err(dev, "%s: invalid max-clock-frequency-hz property, %d\n",
-                               __func__, ret);
-               goto out;
+               dev_err(dev, "%s: error reading array %d\n",
+                               "freq-table-hz", ret);
+               goto free_clkfreq;
        }
 
-       for (i = 0; i < cnt; i++) {
+       for (i = 0; i < sz; i += 2) {
                ret = of_property_read_string_index(np,
-                               "clock-names", i, (const char **)&name);
+                               "clock-names", i/2, (const char **)&name);
                if (ret)
-                       goto out;
+                       goto free_clkfreq;
 
                clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL);
                if (!clki) {
                        ret = -ENOMEM;
-                       goto out;
+                       goto free_clkfreq;
                }
 
-               clki->max_freq = clkfreq[i];
+               clki->min_freq = clkfreq[i];
+               clki->max_freq = clkfreq[i+1];
                clki->name = kstrdup(name, GFP_KERNEL);
+               dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
+                               clki->min_freq, clki->max_freq, clki->name);
                list_add_tail(&clki->list, &hba->clk_list_head);
        }
-out:
+free_clkfreq:
        kfree(clkfreq);
+out:
        return ret;
 }
 

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 29d34d3aa5ee45a4aa48fdd03a6b8f965a15aa22..ac72a6daf50e5ee596a6b0282f5306f805f12c3c 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -209,6 +209,7 @@ struct ufs_dev_cmd {
  * @clk: clock node
  * @name: clock name
  * @max_freq: maximum frequency supported by the clock
+ * @min_freq: min frequency that can be used for clock scaling
  * @enabled: variable to check against multiple enable/disable
  */
 struct ufs_clk_info {
@@ -216,6 +217,7 @@ struct ufs_clk_info {
        struct clk *clk;
        const char *name;
        u32 max_freq;
+       u32 min_freq;
        bool enabled;
 };