PM / OPP: Separate out _generic_set_opp()

Later patches would add support for custom set_opp() callbacks. This
patch separates out the code for _generic_set_opp() handler in order to
prepare for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

3 files changed, 166 insertions, 53 deletions

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index b4da31c5a5eb..e33198ce41b4 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -610,6 +610,69 @@ static int _set_opp_voltage(struct device *dev, struct regulator *reg,
         return ret;
 }
 
+static inline int
+_generic_set_opp_clk_only(struct device *dev, struct clk *clk,
+                          unsigned long old_freq, unsigned long freq)
+{
+        int ret;
+
+        ret = clk_set_rate(clk, freq);
+        if (ret) {
+                dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
+                        ret);
+        }
+
+        return ret;
+}
+
+static int _generic_set_opp(struct dev_pm_set_opp_data *data)
+{
+        struct dev_pm_opp_supply *old_supply = data->old_opp.supplies;
+        struct dev_pm_opp_supply *new_supply = data->new_opp.supplies;
+        unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
+        struct regulator *reg = data->regulators[0];
+        struct device *dev= data->dev;
+        int ret;
+
+        /* This function only supports single regulator per device */
+        if (WARN_ON(data->regulator_count > 1)) {
+                dev_err(dev, "multiple regulators are not supported\n");
+                return -EINVAL;
+        }
+
+        /* Scaling up? Scale voltage before frequency */
+        if (freq > old_freq) {
+                ret = _set_opp_voltage(dev, reg, new_supply);
+                if (ret)
+                        goto restore_voltage;
+        }
+
+        /* Change frequency */
+        ret = _generic_set_opp_clk_only(dev, data->clk, old_freq, freq);
+        if (ret)
+                goto restore_voltage;
+
+        /* Scaling down? Scale voltage after frequency */
+        if (freq < old_freq) {
+                ret = _set_opp_voltage(dev, reg, new_supply);
+                if (ret)
+                        goto restore_freq;
+        }
+
+        return 0;
+
+restore_freq:
+        if (_generic_set_opp_clk_only(dev, data->clk, freq, old_freq))
+                dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
+                        __func__, old_freq);
+restore_voltage:
+        /* This shouldn't harm even if the voltages weren't updated earlier */
+        if (old_supply->u_volt)
+                _set_opp_voltage(dev, reg, old_supply);
+
+        return ret;
+}
+
 /**
  * dev_pm_opp_set_rate() - Configure new OPP based on frequency
  * @dev:         device for which we do this operation
@@ -623,12 +686,12 @@ static int _set_opp_voltage(struct device *dev, struct regulator *reg,
 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 {
         struct opp_table *opp_table;
+        unsigned long freq, old_freq;
         struct dev_pm_opp *old_opp, *opp;
-        struct regulator *reg = ERR_PTR(-ENXIO);
+        struct regulator **regulators;
+        struct dev_pm_set_opp_data *data;
         struct clk *clk;
-        unsigned long freq, old_freq;
-        struct dev_pm_opp_supply old_supply, new_supply;
-        int ret;
+        int ret, size;
 
         if (unlikely(!target_freq)) {
                 dev_err(dev, "%s: Invalid target frequency %lu\n", __func__,
@@ -677,64 +740,36 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
                 return ret;
         }
 
-        if (opp_table->regulators) {
-                /* This function only supports single regulator per device */
-                if (WARN_ON(opp_table->regulator_count > 1)) {
-                        dev_err(dev, "multiple regulators not supported\n");
-                        rcu_read_unlock();
-                        return -EINVAL;
-                }
+        dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n", __func__,
+                old_freq, freq);
 
-                reg = opp_table->regulators[0];
+        regulators = opp_table->regulators;
+
+        /* Only frequency scaling */
+        if (!regulators) {
+                rcu_read_unlock();
+                return _generic_set_opp_clk_only(dev, clk, old_freq, freq);
         }
 
+        data = opp_table->set_opp_data;
+        data->regulators = regulators;
+        data->regulator_count = opp_table->regulator_count;
+        data->clk = clk;
+        data->dev = dev;
+
+        data->old_opp.rate = old_freq;
+        size = sizeof(*opp->supplies) * opp_table->regulator_count;
         if (IS_ERR(old_opp))
-                old_supply.u_volt = 0;
+                memset(data->old_opp.supplies, 0, size);
         else
-                memcpy(&old_supply, old_opp->supplies, sizeof(old_supply));
+                memcpy(data->old_opp.supplies, old_opp->supplies, size);
 
-        memcpy(&new_supply, opp->supplies, sizeof(new_supply));
+        data->new_opp.rate = freq;
+        memcpy(data->new_opp.supplies, opp->supplies, size);
 
         rcu_read_unlock();
 
-        /* Scaling up? Scale voltage before frequency */
-        if (freq > old_freq) {
-                ret = _set_opp_voltage(dev, reg, &new_supply);
-                if (ret)
-                        goto restore_voltage;
-        }
-
-        /* Change frequency */
-
-        dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
-                __func__, old_freq, freq);
-
-        ret = clk_set_rate(clk, freq);
-        if (ret) {
-                dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
-                        ret);
-                goto restore_voltage;
-        }
-
-        /* Scaling down? Scale voltage after frequency */
-        if (freq < old_freq) {
-                ret = _set_opp_voltage(dev, reg, &new_supply);
-                if (ret)
-                        goto restore_freq;
-        }
-
-        return 0;
-
-restore_freq:
-        if (clk_set_rate(clk, old_freq))
-                dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
-                        __func__, old_freq);
-restore_voltage:
-        /* This shouldn't harm even if the voltages weren't updated earlier */
-        if (old_supply.u_volt)
-                _set_opp_voltage(dev, reg, &old_supply);
-
-        return ret;
+        return _generic_set_opp(data);
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate);
 
@@ -1368,6 +1403,38 @@ unlock:
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);
 
+static int _allocate_set_opp_data(struct opp_table *opp_table)
+{
+        struct dev_pm_set_opp_data *data;
+        int len, count = opp_table->regulator_count;
+
+        if (WARN_ON(!count))
+                return -EINVAL;
+
+        /* space for set_opp_data */
+        len = sizeof(*data);
+
+        /* space for old_opp.supplies and new_opp.supplies */
+        len += 2 * sizeof(struct dev_pm_opp_supply) * count;
+
+        data = kzalloc(len, GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        data->old_opp.supplies = (void *)(data + 1);
+        data->new_opp.supplies = data->old_opp.supplies + count;
+
+        opp_table->set_opp_data = data;
+
+        return 0;
+}
+
+static void _free_set_opp_data(struct opp_table *opp_table)
+{
+        kfree(opp_table->set_opp_data);
+        opp_table->set_opp_data = NULL;
+}
+
 /**
  * dev_pm_opp_set_regulators() - Set regulator names for the device
  * @dev: Device for which regulator name is being set.
@@ -1437,6 +1504,11 @@ struct opp_table *dev_pm_opp_set_regulators(struct device *dev,
 
         opp_table->regulator_count = count;
 
+        /* Allocate block only once to pass to set_opp() routines */
+        ret = _allocate_set_opp_data(opp_table);
+        if (ret)
+                goto free_regulators;
+
         mutex_unlock(&opp_table_lock);
         return opp_table;
 
@@ -1446,6 +1518,7 @@ free_regulators:
 
         kfree(opp_table->regulators);
         opp_table->regulators = NULL;
+        opp_table->regulator_count = 0;
 err:
         _remove_opp_table(opp_table);
 unlock:
@@ -1482,6 +1555,8 @@ void dev_pm_opp_put_regulators(struct opp_table *opp_table)
         for (i = opp_table->regulator_count - 1; i >= 0; i--)
                 regulator_put(opp_table->regulators[i]);
 
+        _free_set_opp_data(opp_table);
+
         kfree(opp_table->regulators);
         opp_table->regulators = NULL;
         opp_table->regulator_count = 0;
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h
index 5b0f7e53bede..a05e43912c6b 100644
--- a/drivers/base/power/opp/opp.h
+++ b/drivers/base/power/opp/opp.h
@@ -141,6 +141,7 @@ enum opp_table_access {
  * @clk: Device's clock handle
  * @regulators: Supply regulators
  * @regulator_count: Number of power supply regulators
+ * @set_opp_data: Data to be passed to set_opp callback
  * @dentry:     debugfs dentry pointer of the real device directory (not links).
  * @dentry_name: Name of the real dentry.
  *
@@ -178,6 +179,8 @@ struct opp_table {
         struct regulator **regulators;
         unsigned int regulator_count;
 
+        struct dev_pm_set_opp_data *set_opp_data;
+
 #ifdef CONFIG_DEBUG_FS
         struct dentry *dentry;
         char dentry_name[NAME_MAX];
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 9a825ae78653..779b40a9287d 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -17,6 +17,8 @@
 #include <linux/err.h>
 #include <linux/notifier.h>
 
+struct clk;
+struct regulator;
 struct dev_pm_opp;
 struct device;
 struct opp_table;
@@ -41,6 +43,39 @@ struct dev_pm_opp_supply {
         unsigned long u_amp;
 };
 
+/**
+ * struct dev_pm_opp_info - OPP freq/voltage/current values
+ * @rate:       Target clk rate in hz
+ * @supplies:   Array of voltage/current values for all power supplies
+ *
+ * This structure stores the freq/voltage/current values for a single OPP.
+ */
+struct dev_pm_opp_info {
+        unsigned long rate;
+        struct dev_pm_opp_supply *supplies;
+};
+
+/**
+ * struct dev_pm_set_opp_data - Set OPP data
+ * @old_opp:    Old OPP info
+ * @new_opp:    New OPP info
+ * @regulators: Array of regulator pointers
+ * @regulator_count: Number of regulators
+ * @clk:        Pointer to clk
+ * @dev:        Pointer to the struct device
+ *
+ * This structure contains all information required for setting an OPP.
+ */
+struct dev_pm_set_opp_data {
+        struct dev_pm_opp_info old_opp;
+        struct dev_pm_opp_info new_opp;
+
+        struct regulator **regulators;
+        unsigned int regulator_count;
+        struct clk *clk;
+        struct device *dev;
+};
+
 #if defined(CONFIG_PM_OPP)
 
 unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp);