cpufreq: mt8173: Move resources allocation into ->probe()

Since the return value of ->init() of cpufreq driver is not propagated
to the device driver model now, move resources allocation into
->probe() to handle -EPROBE_DEFER properly.

Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 68 insertions, 24 deletions

diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c
index 9d0fe37b4c3e..fd601b92f5ec 100644
--- a/drivers/cpufreq/mt8173-cpufreq.c
+++ b/drivers/cpufreq/mt8173-cpufreq.c
@@ -41,16 +41,35 @@
  * the original PLL becomes stable at target frequency.
  */
 struct mtk_cpu_dvfs_info {
+        struct cpumask cpus;
         struct device *cpu_dev;
         struct regulator *proc_reg;
         struct regulator *sram_reg;
         struct clk *cpu_clk;
         struct clk *inter_clk;
         struct thermal_cooling_device *cdev;
+        struct list_head list_head;
         int intermediate_voltage;
         bool need_voltage_tracking;
 };
 
+static LIST_HEAD(dvfs_info_list);
+
+static struct mtk_cpu_dvfs_info *mtk_cpu_dvfs_info_lookup(int cpu)
+{
+        struct mtk_cpu_dvfs_info *info;
+        struct list_head *list;
+
+        list_for_each(list, &dvfs_info_list) {
+                info = list_entry(list, struct mtk_cpu_dvfs_info, list_head);
+
+                if (cpumask_test_cpu(cpu, &info->cpus))
+                        return info;
+        }
+
+        return NULL;
+}
+
 static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
                                         int new_vproc)
 {
@@ -402,6 +421,9 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
          */
         info->need_voltage_tracking = !IS_ERR(sram_reg);
 
+        /* CPUs in the same cluster share a clock and power domain. */
+        cpumask_copy(&info->cpus, &cpu_topology[cpu].core_sibling);
+
         return 0;
 
 out_free_opp_table:
@@ -440,22 +462,18 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy)
         struct cpufreq_frequency_table *freq_table;
         int ret;
 
-        info = kzalloc(sizeof(*info), GFP_KERNEL);
-        if (!info)
-                return -ENOMEM;
-
-        ret = mtk_cpu_dvfs_info_init(info, policy->cpu);
-        if (ret) {
-                pr_err("%s failed to initialize dvfs info for cpu%d\n",
-                       __func__, policy->cpu);
-                goto out_free_dvfs_info;
+        info = mtk_cpu_dvfs_info_lookup(policy->cpu);
+        if (!info) {
+                pr_err("dvfs info for cpu%d is not initialized.\n",
+                       policy->cpu);
+                return -EINVAL;
         }
 
         ret = dev_pm_opp_init_cpufreq_table(info->cpu_dev, &freq_table);
         if (ret) {
                 pr_err("failed to init cpufreq table for cpu%d: %d\n",
                        policy->cpu, ret);
-                goto out_release_dvfs_info;
+                return ret;
         }
 
         ret = cpufreq_table_validate_and_show(policy, freq_table);
@@ -464,8 +482,7 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy)
                 goto out_free_cpufreq_table;
         }
 
-        /* CPUs in the same cluster share a clock and power domain. */
-        cpumask_copy(policy->cpus, &cpu_topology[policy->cpu].core_sibling);
+        cpumask_copy(policy->cpus, &info->cpus);
         policy->driver_data = info;
         policy->clk = info->cpu_clk;
 
@@ -473,13 +490,6 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy)
 
 out_free_cpufreq_table:
         dev_pm_opp_free_cpufreq_table(info->cpu_dev, &freq_table);
-
-out_release_dvfs_info:
-        mtk_cpu_dvfs_info_release(info);
-
-out_free_dvfs_info:
-        kfree(info);
-
         return ret;
 }
 
@@ -489,8 +499,6 @@ static int mtk_cpufreq_exit(struct cpufreq_policy *policy)
 
         cpufreq_cooling_unregister(info->cdev);
         dev_pm_opp_free_cpufreq_table(info->cpu_dev, &policy->freq_table);
-        mtk_cpu_dvfs_info_release(info);
-        kfree(info);
 
         return 0;
 }
@@ -510,11 +518,47 @@ static struct cpufreq_driver mt8173_cpufreq_driver = {
 
 static int mt8173_cpufreq_probe(struct platform_device *pdev)
 {
-        int ret;
+        struct mtk_cpu_dvfs_info *info;
+        struct list_head *list, *tmp;
+        int cpu, ret;
+
+        for_each_possible_cpu(cpu) {
+                info = mtk_cpu_dvfs_info_lookup(cpu);
+                if (info)
+                        continue;
+
+                info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+                if (!info) {
+                        ret = -ENOMEM;
+                        goto release_dvfs_info_list;
+                }
+
+                ret = mtk_cpu_dvfs_info_init(info, cpu);
+                if (ret) {
+                        dev_err(&pdev->dev,
+                                "failed to initialize dvfs info for cpu%d\n",
+                                cpu);
+                        goto release_dvfs_info_list;
+                }
+
+                list_add(&info->list_head, &dvfs_info_list);
+        }
 
         ret = cpufreq_register_driver(&mt8173_cpufreq_driver);
-        if (ret)
-                pr_err("failed to register mtk cpufreq driver\n");
+        if (ret) {
+                dev_err(&pdev->dev, "failed to register mtk cpufreq driver\n");
+                goto release_dvfs_info_list;
+        }
+
+        return 0;
+
+release_dvfs_info_list:
+        list_for_each_safe(list, tmp, &dvfs_info_list) {
+                info = list_entry(list, struct mtk_cpu_dvfs_info, list_head);
+
+                mtk_cpu_dvfs_info_release(info);
+                list_del(list);
+        }
 
         return ret;
 }