Re: [PATCH 3/4] devfreq: exynos4: Add ppmu's clock control and code clean about regulator control

Chanwoo Choi
2014-03-13T02:15:36Z

Hi Batlomiej,

On 03/13/2014 12:17 AM, Bartlomiej Zolnierkiewicz wrote:
>
> Hi,
>
> On Wednesday, March 12, 2014 08:48:01 PM Chanwoo Choi wrote:
>> There are not the clock controller of ppmudmc0/1. This patch control the clock
>> of ppmudmc0/1 which is used for monitoring memory bus utilization.
>>
>> Also, this patch code clean about regulator control and free resource
>> when calling exit/remove function.
>>
>> For example,
>> busfreq@106A0000 {
>> compatible = "samsung,exynos4x12-busfreq";
>>
>> /* Clock for PPMUDMC0/1 */
>> clocks = <&clock CLK_PPMUDMC0>, <&clock CLK_PPMUDMC1>;
>> clock-names = "ppmudmc0", "ppmudmc1";
>>
>> /* Regulator for MIF/INT block */
>> vdd_mif-supply = <&buck1_reg>;
>> vdd_int-supply = <&buck3_reg>;
>> };
>
> This should be in Documentation/devicetree/bindings/ documentation.

OK, I will add documentation about it.

>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> ---
>> drivers/devfreq/exynos/exynos4_bus.c | 107 ++++++++++++++++++++++++++++++-----
>> 1 file changed, 93 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/devfreq/exynos/exynos4_bus.c b/drivers/devfreq/exynos/exynos4_bus.c
>> index 16fb3cb..0c5b99e 100644
>> --- a/drivers/devfreq/exynos/exynos4_bus.c
>> +++ b/drivers/devfreq/exynos/exynos4_bus.c
>> @@ -62,6 +62,11 @@ enum exynos_ppmu_idx {
>> PPMU_END,
>> };
>>
>> +static const char *exynos_ppmu_clk_name[] = {
>> + [PPMU_DMC0] = "ppmudmc0",
>> + [PPMU_DMC1] = "ppmudmc1",
>> +};
>> +
>> #define EX4210_LV_MAX LV_2
>> #define EX4x12_LV_MAX LV_4
>> #define EX4210_LV_NUM (LV_2 + 1)
>> @@ -86,6 +91,7 @@ struct busfreq_data {
>> struct regulator *vdd_mif; /* Exynos4412/4212 only */
>> struct busfreq_opp_info curr_oppinfo;
>> struct exynos_ppmu ppmu[PPMU_END];
>> + struct clk *clk_ppmu[PPMU_END];
>>
>> struct notifier_block pm_notifier;
>> struct mutex lock;
>> @@ -722,8 +728,26 @@ static int exynos4_bus_get_dev_status(struct device *dev,
>> static void exynos4_bus_exit(struct device *dev)
>> {
>> struct busfreq_data *data = dev_get_drvdata(dev);
>> + int i;
>>
>> - devfreq_unregister_opp_notifier(dev, data->devfreq);
>> + /*
>> + * Un-map memory man and disable regulator/clocks
>> + * to prevent power leakage.
>> + */
>> + regulator_disable(data->vdd_int);
>> + if (data->type == TYPE_BUSF_EXYNOS4x12)
>> + regulator_disable(data->vdd_mif);
>> +
>> + for (i = 0; i < PPMU_END; i++) {
>> + if (data->clk_ppmu[i])
>> + clk_disable_unprepare(data->clk_ppmu[i]);
>> + }
>> +
>> + for (i = 0; i < PPMU_END; i++) {
>> + if (data->ppmu[i].hw_base)
>> + iounmap(data->ppmu[i].hw_base);
>> +
>> + }
>> }
>>
>> static struct devfreq_dev_profile exynos4_devfreq_profile = {
>> @@ -987,6 +1011,7 @@ static int exynos4_busfreq_parse_dt(struct busfreq_data *data)
>> {
>> struct device *dev = data->dev;
>> struct device_node *np = dev->of_node;
>> + const char **clk_name = exynos_ppmu_clk_name;
>> int i, ret;
>>
>> if (!np) {
>> @@ -1005,8 +1030,67 @@ static int exynos4_busfreq_parse_dt(struct busfreq_data *data)
>> }
>> }
>>
>> + /*
>> + * Get PPMU's clocks to control them. But, if PPMU's clocks
>> + * is default 'pass' state, this driver don't need control
>> + * PPMU's clock.
>> + */
>> + for (i = 0; i < PPMU_END; i++) {
>> + data->clk_ppmu[i] = devm_clk_get(dev, clk_name[i]);
>> + if (IS_ERR_OR_NULL(data->clk_ppmu[i])) {
>> + dev_warn(dev, "Cannot get %s clock\n", clk_name[i]);
>> + data->clk_ppmu[i] = NULL;
>> + }
>> +
>> + ret = clk_prepare_enable(data->clk_ppmu[i]);
>> + if (ret < 0) {
>> + dev_warn(dev, "Cannot enable %s clock\n", clk_name[i]);
>> + data->clk_ppmu[i] = NULL;
>> + goto err_clocks;
>> + }
>> + }
>> +
>> +
>> + /* Get regulators to control voltage of int/mif block */
>> + data->vdd_int = devm_regulator_get(dev, "vdd_int");
>> + if (IS_ERR(data->vdd_int)) {
>> + dev_err(dev, "Failed to get the regulator of vdd_int\n");
>> + ret = PTR_ERR(data->vdd_int);
>> + goto err_clocks;
>> + }
>> + ret = regulator_enable(data->vdd_int);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to enable regulator of vdd_int\n");
>> + goto err_clocks;
>> + }
>> +
>> + switch (data->type) {
>> + case TYPE_BUSF_EXYNOS4x12:
>> + data->vdd_mif = devm_regulator_get(dev, "vdd_mif");
>> + if (IS_ERR(data->vdd_mif)) {
>> + dev_err(dev, "Failed to get the regulator vdd_mif\n");
>> + ret = PTR_ERR(data->vdd_mif);
>> + goto err_clocks;
>
> This won't disable vdd_int regulator.

I don't understand. This patch contro/enable always vdd_int regualor as following:
>> + data->vdd_int = devm_regulator_get(dev, "vdd_int");
>> + ret = regulator_enable(data->vdd_int);
You can check this code on this patch. upper

>
>> + }
>> + ret = regulator_enable(data->vdd_mif);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to enable regulator of vdd_mif\n");
>> + goto err_clocks;
>
> ditto

>
>> + }
>> + break;
>> + case TYPE_BUSF_EXYNOS4210:
>> + default:
>> + dev_err(data->dev, "Unknown device type\n");
>> + return -EINVAL;
>
> This looks very wrong for Exynos4210.

What is wrong for Exynos4210?
Always, exynos4210/exynos4x12 control vdd_int regulator uppper this patch.

>
>> + };
>> +
>> return 0;
>>
>> +err_clocks:
>> + for (i = 0; i < PPMU_END; i++) {
>> + if (data->clk_ppmu[i])
>> + clk_disable_unprepare(data->clk_ppmu[i]);
>> + }
>> err_iomap:
>> for (i = 0; i < PPMU_END; i++) {
>> if (data->ppmu[i].hw_base)
>> @@ -1068,19 +1152,6 @@ static int exynos4_busfreq_probe(struct platform_device *pdev)
>> if (err)
>> return err;
>>
>> - data->vdd_int = devm_regulator_get(dev, "vdd_int");
>> - if (IS_ERR(data->vdd_int)) {
>> - dev_err(dev, "Cannot get the regulator \"vdd_int\"\n");
>> - return PTR_ERR(data->vdd_int);
>> - }
>> - if (data->type == TYPE_BUSF_EXYNOS4x12) {
>> - data->vdd_mif = devm_regulator_get(dev, "vdd_mif");
>> - if (IS_ERR(data->vdd_mif)) {
>> - dev_err(dev, "Cannot get the regulator \"vdd_mif\"\n");
>> - return PTR_ERR(data->vdd_mif);
>> - }
>> - }
>> -
>> rcu_read_lock();
>> opp = dev_pm_opp_find_freq_floor(dev,
>> &exynos4_devfreq_profile.initial_freq);
>> @@ -1133,6 +1204,11 @@ err_notifier_opp:
>> devfreq_remove_device(data->devfreq);
>> err_opp:
>
> Disabling of regulators on failure is missing here.

OK, I'll control regulator.

Best Regard,
Chanwoo Choi