[PATCH v3] cpufreq: mt8173: move resources allocation into ->probe()

Pi-Cheng Chen
2015-12-10T03:48:24Z

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>
---
v2->v3:
- rename get_dvfs_info() as mtk_cpu_dvfs_info_lookup()
- fix some minor issues of v2
v1->v2:
- fix error handling path in ->probe()
---
drivers/cpufreq/mt8173-cpufreq.c | 92 +++++++++++++++++++++++++++++-----------
1 file changed, 68 insertions(+), 24 deletions(-)

diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c
index 9d0fe37..fd601b9 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;
}
--
1.9.1