Re: [PATCHv2 3/8] devfreq: exynos4: Add ppmu's clock control and code clean about regulator control

From: Chanwoo Choi
Date: Tue Mar 18 2014 - 22:44:17 EST


Hi Tomasz,

On 03/18/2014 08:13 PM, Tomasz Figa wrote:
> Hi Chanwoo,
>
> On 17.03.2014 06:59, Chanwoo Choi wrote:
>> Hi Tomasz,
>>
>> On 03/17/2014 11:51 AM, Chanwoo Choi wrote:
>>> Hi Tomasz,
>>>
>>> On 03/15/2014 02:42 AM, Tomasz Figa wrote:
>>>> Hi Chanwoo,
>>>>
>>>> On 13.03.2014 09:17, 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>;
>>>>> };
>>>>>
>>>>> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
>>
>> I modify this patch according your comment as following:
>>
>> Best Regards,
>> Chanwoo Choi
>>
>>> From c8f2fbc4c1166ec02fb2ad46164bc7ed9118721b Mon Sep 17 00:00:00 2001
>> From: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
>> Date: Fri, 14 Mar 2014 12:05:54 +0900
>> Subject: [PATCH] devfreq: exynos4: Add ppmu's clock control and code clean
>> about regulator control
>>
>> 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>;
>> };
>>
>> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
>> ---
>> drivers/devfreq/exynos/exynos4_bus.c | 97 +++++++++++++++++++++++++++++++-----
>> 1 file changed, 84 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/devfreq/exynos/exynos4_bus.c b/drivers/devfreq/exynos/exynos4_bus.c
>> index 4c630fb..3956bcc 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;
>> @@ -724,6 +730,17 @@ static void exynos4_bus_exit(struct device *dev)
>> struct busfreq_data *data = dev_get_drvdata(dev);
>> int i;
>>
>> + /*
>> + * Un-map memory map 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++)
>> + clk_disable_unprepare(data->clk_ppmu[i]);
>> +
>> for (i = 0; i < PPMU_END; i++)
>> iounmap(data->ppmu[i].hw_base);
>> }
>> @@ -989,6 +1006,7 @@ 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 = 0;
>>
>> if (!np) {
>> @@ -1006,8 +1024,67 @@ static int exynos4_busfreq_parse_dt(struct busfreq_data *data)
>> }
>> }
>>
>> + for (i = 0; i < PPMU_END; i++) {
>> + data->clk_ppmu[i] = devm_clk_get(dev, clk_name[i]);
>> + if (IS_ERR(data->clk_ppmu[i])) {
>> + dev_warn(dev, "Failed to get %s clock\n", clk_name[i]);
>
> dev_err() since this is an error.

OK, I'll fix it.

>
>> + goto err_clocks;
>> + }
>> +
>> + ret = clk_prepare_enable(data->clk_ppmu[i]);
>> + if (ret < 0) {
>> + dev_warn(dev, "Failed to enable %s clock\n", clk_name[i]);
>
> Ditto.

OK, I'll fix it.

>
>> + data->clk_ppmu[i] = NULL;
>> + goto err_clocks;
>> + }
>> + }
>> +
>> + /* Get regulator to control voltage of int 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_EXYNOS4210:
>> + break;
>
> Do you need to use switch here? Wouldn't a simple if (data->type == TYPE_BUSF_EXYNOS4x12) work as well, resulting with simpler code?

OK, I'll fix it.

>
> However I would expect this code to be completely removed, after defining DT bindings in a way allowing you to completely drop such SoC type enums. Please see my other reply for explanation of Exynos power plane DT bindings concept.

OK, I agree your suggestion about Exynos power plane DT bindings concept.

I'll apply "Exynos power plane" to exynos4 busfreq driver on next step
after defining Exynos power plane DT bindings.

>
>> + case TYPE_BUSF_EXYNOS4x12:
>> + /* Get regulator to control voltage of mif blk if 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_regulator;
>> + }
>> + ret = regulator_enable(data->vdd_mif);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to enable regulator of vdd_mif\n");
>> + goto err_regulator;
>> + }
>> + break;
>> + default:
>> + dev_err(dev, "Unknown device type : %d\n", data->type);
>> + return -EINVAL;
>> + };
>> +
>> return 0;
>>
>> +err_regulator:
>> + regulator_disable(data->vdd_int);
>> +err_clocks:
>> + for (i = 0; i < PPMU_END; i++) {
>> + if (IS_ERR(data->clk_ppmu[i]))
>> + continue;
>> + else
>
> if (!IS_ERR(...))
>
>> + clk_disable_unprepare(data->clk_ppmu[i]);
>> + }
>
> Otherwise looks good.

Thanks for your review.

Best Regards,
Chanwoo Choi





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