Merge branch 'linux-linaro-lsk-v4.4-android' of git://git.linaro.org/kernel/linux...
[firefly-linux-kernel-4.4.55.git] / drivers / cpufreq / cpufreq-dt.c
index 6f80ce56b4ecad6eecc3fed0f44a2fa8b6de1bf8..f951f911786e086b2b6dc9d615018eb235347dbe 100644 (file)
@@ -31,9 +31,7 @@
 
 struct private_data {
        struct device *cpu_dev;
-       struct regulator *cpu_reg;
        struct thermal_cooling_device *cdev;
-       unsigned int voltage_tolerance; /* in percentage */
        const char *reg_name;
 };
 
@@ -45,181 +43,110 @@ static struct freq_attr *cpufreq_dt_attr[] = {
 
 static int set_target(struct cpufreq_policy *policy, unsigned int index)
 {
-       struct dev_pm_opp *opp;
-       struct cpufreq_frequency_table *freq_table = policy->freq_table;
-       struct clk *cpu_clk = policy->clk;
        struct private_data *priv = policy->driver_data;
-       struct device *cpu_dev = priv->cpu_dev;
-       struct regulator *cpu_reg = priv->cpu_reg;
-       unsigned long volt = 0, tol = 0;
-       int volt_old = 0;
-       unsigned int old_freq, new_freq;
-       long freq_Hz, freq_exact;
-       int ret;
-
-       freq_Hz = clk_round_rate(cpu_clk, freq_table[index].frequency * 1000);
-       if (freq_Hz <= 0)
-               freq_Hz = freq_table[index].frequency * 1000;
-
-       freq_exact = freq_Hz;
-       new_freq = freq_Hz / 1000;
-       old_freq = clk_get_rate(cpu_clk) / 1000;
-
-       if (!IS_ERR(cpu_reg)) {
-               unsigned long opp_freq;
-
-               rcu_read_lock();
-               opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_Hz);
-               if (IS_ERR(opp)) {
-                       rcu_read_unlock();
-                       dev_err(cpu_dev, "failed to find OPP for %ld\n",
-                               freq_Hz);
-                       return PTR_ERR(opp);
-               }
-               volt = dev_pm_opp_get_voltage(opp);
-               opp_freq = dev_pm_opp_get_freq(opp);
-               rcu_read_unlock();
-               tol = volt * priv->voltage_tolerance / 100;
-               volt_old = regulator_get_voltage(cpu_reg);
-               dev_dbg(cpu_dev, "Found OPP: %ld kHz, %ld uV\n",
-                       opp_freq / 1000, volt);
-       }
-
-       dev_dbg(cpu_dev, "%u MHz, %d mV --> %u MHz, %ld mV\n",
-               old_freq / 1000, (volt_old > 0) ? volt_old / 1000 : -1,
-               new_freq / 1000, volt ? volt / 1000 : -1);
-
-       /* scaling up?  scale voltage before frequency */
-       if (!IS_ERR(cpu_reg) && new_freq > old_freq) {
-               ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
-               if (ret) {
-                       dev_err(cpu_dev, "failed to scale voltage up: %d\n",
-                               ret);
-                       return ret;
-               }
-       }
-
-       ret = clk_set_rate(cpu_clk, freq_exact);
-       if (ret) {
-               dev_err(cpu_dev, "failed to set clock rate: %d\n", ret);
-               if (!IS_ERR(cpu_reg) && volt_old > 0)
-                       regulator_set_voltage_tol(cpu_reg, volt_old, tol);
-               return ret;
-       }
 
-       /* scaling down?  scale voltage after frequency */
-       if (!IS_ERR(cpu_reg) && new_freq < old_freq) {
-               ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
-               if (ret) {
-                       dev_err(cpu_dev, "failed to scale voltage down: %d\n",
-                               ret);
-                       clk_set_rate(cpu_clk, old_freq * 1000);
-               }
-       }
-
-       return ret;
+       return dev_pm_opp_set_rate(priv->cpu_dev,
+                                  policy->freq_table[index].frequency * 1000);
 }
 
 /*
  * An earlier version of opp-v1 bindings used to name the regulator
  * "cpu0-supply", we still need to handle that for backwards compatibility.
  */
-static const char *find_supply_name(struct device *dev, struct device_node *np)
+static const char *find_supply_name(struct device *dev)
 {
+       struct device_node *np;
        struct property *pp;
        int cpu = dev->id;
+       const char *name = NULL;
+
+       np = of_node_get(dev->of_node);
+
+       /* This must be valid for sure */
+       if (WARN_ON(!np))
+               return NULL;
 
        /* Try "cpu0" for older DTs */
        if (!cpu) {
                pp = of_find_property(np, "cpu0-supply", NULL);
-               if (pp)
-                       return "cpu0";
+               if (pp) {
+                       name = "cpu0";
+                       goto node_put;
+               }
        }
 
        pp = of_find_property(np, "cpu-supply", NULL);
-       if (pp)
-               return "cpu";
+       if (pp) {
+               name = "cpu";
+               goto node_put;
+       }
 
        dev_dbg(dev, "no regulator for cpu%d\n", cpu);
-       return NULL;
+node_put:
+       of_node_put(np);
+       return name;
 }
 
-static int allocate_resources(int cpu, struct device **cdev,
-                             struct regulator **creg, struct clk **cclk)
+static int resources_available(void)
 {
        struct device *cpu_dev;
        struct regulator *cpu_reg;
        struct clk *cpu_clk;
        int ret = 0;
-       char *reg_cpu0 = "cpu0", *reg_cpu = "cpu", *reg;
+       const char *name;
 
-       cpu_dev = get_cpu_device(cpu);
+       cpu_dev = get_cpu_device(0);
        if (!cpu_dev) {
-               pr_err("failed to get cpu%d device\n", cpu);
+               pr_err("failed to get cpu0 device\n");
                return -ENODEV;
        }
 
-       /* Try "cpu0" for older DTs */
-       if (!cpu)
-               reg = reg_cpu0;
-       else
-               reg = reg_cpu;
-
-try_again:
-       cpu_reg = regulator_get_optional(cpu_dev, reg);
-       ret = PTR_ERR_OR_ZERO(cpu_reg);
+       cpu_clk = clk_get(cpu_dev, NULL);
+       ret = PTR_ERR_OR_ZERO(cpu_clk);
        if (ret) {
                /*
-                * If cpu's regulator supply node is present, but regulator is
-                * not yet registered, we should try defering probe.
+                * If cpu's clk node is present, but clock is not yet
+                * registered, we should try defering probe.
                 */
-               if (ret == -EPROBE_DEFER) {
-                       dev_dbg(cpu_dev, "cpu%d regulator not ready, retry\n",
-                               cpu);
-                       return ret;
-               }
-
-               /* Try with "cpu-supply" */
-               if (reg == reg_cpu0) {
-                       reg = reg_cpu;
-                       goto try_again;
-               }
+               if (ret == -EPROBE_DEFER)
+                       dev_dbg(cpu_dev, "clock not ready, retry\n");
+               else
+                       dev_err(cpu_dev, "failed to get clock: %d\n", ret);
 
-               dev_dbg(cpu_dev, "no regulator for cpu%d: %d\n", cpu, ret);
+               return ret;
        }
 
-       cpu_clk = clk_get(cpu_dev, NULL);
-       ret = PTR_ERR_OR_ZERO(cpu_clk);
-       if (ret) {
-               /* put regulator */
-               if (!IS_ERR(cpu_reg))
-                       regulator_put(cpu_reg);
+       clk_put(cpu_clk);
 
+       name = find_supply_name(cpu_dev);
+       /* Platform doesn't require regulator */
+       if (!name)
+               return 0;
+
+       cpu_reg = regulator_get_optional(cpu_dev, name);
+       ret = PTR_ERR_OR_ZERO(cpu_reg);
+       if (ret) {
                /*
-                * If cpu's clk node is present, but clock is not yet
-                * registered, we should try defering probe.
+                * If cpu's regulator supply node is present, but regulator is
+                * not yet registered, we should try defering probe.
                 */
                if (ret == -EPROBE_DEFER)
-                       dev_dbg(cpu_dev, "cpu%d clock not ready, retry\n", cpu);
+                       dev_dbg(cpu_dev, "cpu0 regulator not ready, retry\n");
                else
-                       dev_err(cpu_dev, "failed to get cpu%d clock: %d\n", cpu,
-                               ret);
-       } else {
-               *cdev = cpu_dev;
-               *creg = cpu_reg;
-               *cclk = cpu_clk;
+                       dev_dbg(cpu_dev, "no regulator for cpu0: %d\n", ret);
+
+               return ret;
        }
 
-       return ret;
+       regulator_put(cpu_reg);
+       return 0;
 }
 
 static int cpufreq_init(struct cpufreq_policy *policy)
 {
        struct cpufreq_frequency_table *freq_table;
-       struct device_node *np;
        struct private_data *priv;
        struct device *cpu_dev;
-       struct regulator *cpu_reg;
        struct clk *cpu_clk;
        struct dev_pm_opp *suspend_opp;
        unsigned int transition_latency;
@@ -227,17 +154,17 @@ static int cpufreq_init(struct cpufreq_policy *policy)
        const char *name;
        int ret;
 
-       ret = allocate_resources(policy->cpu, &cpu_dev, &cpu_reg, &cpu_clk);
-       if (ret) {
-               pr_err("%s: Failed to allocate resources: %d\n", __func__, ret);
-               return ret;
+       cpu_dev = get_cpu_device(policy->cpu);
+       if (!cpu_dev) {
+               pr_err("failed to get cpu%d device\n", policy->cpu);
+               return -ENODEV;
        }
 
-       np = of_node_get(cpu_dev->of_node);
-       if (!np) {
-               dev_err(cpu_dev, "failed to find cpu%d node\n", policy->cpu);
-               ret = -ENOENT;
-               goto out_put_reg_clk;
+       cpu_clk = clk_get(cpu_dev, NULL);
+       if (IS_ERR(cpu_clk)) {
+               ret = PTR_ERR(cpu_clk);
+               dev_err(cpu_dev, "%s: failed to get clk: %d\n", __func__, ret);
+               return ret;
        }
 
        /* Get OPP-sharing information from "operating-points-v2" bindings */
@@ -250,20 +177,20 @@ static int cpufreq_init(struct cpufreq_policy *policy)
                if (ret == -ENOENT)
                        opp_v1 = true;
                else
-                       goto out_node_put;
+                       goto out_put_clk;
        }
 
        /*
         * OPP layer will be taking care of regulators now, but it needs to know
         * the name of the regulator first.
         */
-       name = find_supply_name(cpu_dev, np);
+       name = find_supply_name(cpu_dev);
        if (name) {
                ret = dev_pm_opp_set_regulator(cpu_dev, name);
                if (ret) {
                        dev_err(cpu_dev, "Failed to set regulator for cpu%d: %d\n",
                                policy->cpu, ret);
-                       goto out_node_put;
+                       goto out_put_clk;
                }
        }
 
@@ -313,7 +240,6 @@ static int cpufreq_init(struct cpufreq_policy *policy)
        }
 
        priv->reg_name = name;
-       of_property_read_u32(np, "voltage-tolerance", &priv->voltage_tolerance);
 
        ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
        if (ret) {
@@ -322,9 +248,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
        }
 
        priv->cpu_dev = cpu_dev;
-       priv->cpu_reg = cpu_reg;
        policy->driver_data = priv;
-
        policy->clk = cpu_clk;
 
        rcu_read_lock();
@@ -355,8 +279,6 @@ static int cpufreq_init(struct cpufreq_policy *policy)
 
        policy->cpuinfo.transition_latency = transition_latency;
 
-       of_node_put(np);
-
        return 0;
 
 out_free_cpufreq_table:
@@ -367,12 +289,8 @@ out_free_opp:
        dev_pm_opp_of_cpumask_remove_table(policy->cpus);
        if (name)
                dev_pm_opp_put_regulator(cpu_dev);
-out_node_put:
-       of_node_put(np);
-out_put_reg_clk:
+out_put_clk:
        clk_put(cpu_clk);
-       if (!IS_ERR(cpu_reg))
-               regulator_put(cpu_reg);
 
        return ret;
 }
@@ -388,8 +306,6 @@ static int cpufreq_exit(struct cpufreq_policy *policy)
                dev_pm_opp_put_regulator(priv->cpu_dev);
 
        clk_put(policy->clk);
-       if (!IS_ERR(priv->cpu_reg))
-               regulator_put(priv->cpu_reg);
        kfree(priv);
 
        return 0;
@@ -442,9 +358,6 @@ static struct cpufreq_driver dt_cpufreq_driver = {
 
 static int dt_cpufreq_probe(struct platform_device *pdev)
 {
-       struct device *cpu_dev;
-       struct regulator *cpu_reg;
-       struct clk *cpu_clk;
        int ret;
 
        /*
@@ -454,19 +367,15 @@ static int dt_cpufreq_probe(struct platform_device *pdev)
         *
         * FIXME: Is checking this only for CPU0 sufficient ?
         */
-       ret = allocate_resources(0, &cpu_dev, &cpu_reg, &cpu_clk);
+       ret = resources_available();
        if (ret)
                return ret;
 
-       clk_put(cpu_clk);
-       if (!IS_ERR(cpu_reg))
-               regulator_put(cpu_reg);
-
        dt_cpufreq_driver.driver_data = dev_get_platdata(&pdev->dev);
 
        ret = cpufreq_register_driver(&dt_cpufreq_driver);
        if (ret)
-               dev_err(cpu_dev, "failed register driver: %d\n", ret);
+               dev_err(&pdev->dev, "failed register driver: %d\n", ret);
 
        return ret;
 }