Re: [1/9] thermal: exynos: Adapt to temperature emulation core thermal framework

From: amit kachhap <amit.kachhap@gmail.com>
To: Eduardo Valentin <eduardo.valentin@ti.com>
Cc: linux-pm@vger.kernel.org,
	Thomas Abraham <thomas.abraham@linaro.org>,
	Zhang Rui <rui.zhang@intel.com>,
	linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org,
	Kukjin Kim <kgene.kim@samsung.com>
Subject: Re: [1/9] thermal: exynos: Adapt to temperature emulation core thermal framework
Date: Fri, 12 Apr 2013 16:27:07 +0530	[thread overview]
Message-ID: <CADGdYn7fh6ZDmokpKXLZ+AViR=4HS3JxwjT-AStvuFAwJfVTfw@mail.gmail.com> (raw)
In-Reply-To: <5167101A.2030105@ti.com>

Hi Eduardo,

Thanks for your review comments.

On Fri, Apr 12, 2013 at 1:03 AM, Eduardo Valentin
<eduardo.valentin@ti.com> wrote:
> Hello Amit,
>
> Couple of comments inline.
>
>
> On 26-03-2013 07:33, Amit Daniel Kachhap wrote:
>>
>> This removes the driver specific sysfs support of the temperature
>> emulation and uses the newly added core thermal framework for thermal
>> emulation. An exynos platform specific handler is added to support this.
>>
>> In this patch, the exynos senor(tmu) related code and exynos framework
>> related (thermal zone, cooling devices) code are intentionally kept
>> separate.
>> So an emulated function pointer is passed from sensor to framework. This
>> is
>> beneficial in adding more sensor support using the same framework code
>> which is an ongoing work. The goal is to finally split them totally. Even
>> the existing read_temperature also follows the same execution method.
>>
>> Acked-by: Kukjin Kim <kgene.kim@samsung.com>
>> Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
>>
>> ---
>> Documentation/thermal/exynos_thermal_emulation |    8 +-
>>   drivers/thermal/Kconfig                        |    9 --
>>   drivers/thermal/exynos_thermal.c               |  158
>> ++++++++++--------------
>>   3 files changed, 67 insertions(+), 108 deletions(-)
>>
>> diff --git a/Documentation/thermal/exynos_thermal_emulation
>> b/Documentation/thermal/exynos_thermal_emulation
>> index b73bbfb..36a3e79 100644
>> --- a/Documentation/thermal/exynos_thermal_emulation
>> +++ b/Documentation/thermal/exynos_thermal_emulation
>> @@ -13,11 +13,11 @@ Thermal emulation mode supports software debug for
>> TMU's operation. User can set
>>   manually with software code and TMU will read current temperature from
>> user value not from
>>   sensor's value.
>>
>> -Enabling CONFIG_EXYNOS_THERMAL_EMUL option will make this support in
>> available.
>> -When it's enabled, sysfs node will be created under
>> -/sys/bus/platform/devices/'exynos device name'/ with name of 'emulation'.
>> +Enabling CONFIG_THERMAL_EMULATION option will make this support
>> available.
>> +When it's enabled, sysfs node will be created as
>> +/sys/devices/virtual/thermal/thermal_zone'zone id'/emul_temp.
>>
>> -The sysfs node, 'emulation', will contain value 0 for the initial state.
>> When you input any
>> +The sysfs node, 'emul_node', will contain value 0 for the initial state.
>> When you input any
>>   temperature you want to update to sysfs node, it automatically enable
>> emulation mode and
>>   current temperature will be changed into it.
>>   (Exynos also supports user changable delay time which would be used to
>> delay of
>
>
> not part of this patch but:
> s/changable/changeable
Ok
>
>
>> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
>> index a764f16..da4c19e 100644
>> --- a/drivers/thermal/Kconfig
>> +++ b/drivers/thermal/Kconfig
>> @@ -117,15 +117,6 @@ config EXYNOS_THERMAL
>>           If you say yes here you get support for TMU (Thermal Management
>>           Unit) on SAMSUNG EXYNOS series of SoC.
>>
>> -config EXYNOS_THERMAL_EMUL
>> -       bool "EXYNOS TMU emulation mode support"
>> -       depends on EXYNOS_THERMAL
>> -       help
>> -         Exynos 4412 and 4414 and 5 series has emulation mode on TMU.
>> -         Enable this option will be make sysfs node in exynos thermal
>> platform
>> -         device directory to support emulation mode. With emulation mode
>> sysfs
>> -         node, you can manually input temperature to TMU for simulation
>> purpose.
>> -
>>   config DOVE_THERMAL
>>         tristate "Temperature sensor on Marvell Dove SoCs"
>>         depends on ARCH_DOVE
>> diff --git a/drivers/thermal/exynos_thermal.c
>> b/drivers/thermal/exynos_thermal.c
>> index 46568c0..1cd7837 100644
>> --- a/drivers/thermal/exynos_thermal.c
>> +++ b/drivers/thermal/exynos_thermal.c
>> @@ -100,13 +100,13 @@
>>   #define IDLE_INTERVAL 10000
>>   #define MCELSIUS      1000
>>
>> -#ifdef CONFIG_EXYNOS_THERMAL_EMUL
>> +#ifdef CONFIG_THERMAL_EMULATION
>>   #define EXYNOS_EMUL_TIME      0x57F0
>>   #define EXYNOS_EMUL_TIME_SHIFT        16
>>   #define EXYNOS_EMUL_DATA_SHIFT        8
>>   #define EXYNOS_EMUL_DATA_MASK 0xFF
>>   #define EXYNOS_EMUL_ENABLE    0x1
>> -#endif /* CONFIG_EXYNOS_THERMAL_EMUL */
>> +#endif /* CONFIG_THERMAL_EMULATION */
>>
>
> As the above is only used in one single function, I suggest moving it to
> same ifdef where the function belongs below. It reduces your ifdefery and
> also makes your code cleaner.
Right makes sense.
>
>
>
>>   /* CPU Zone information */
>>   #define PANIC_ZONE      4
>> @@ -145,6 +145,7 @@ struct      thermal_cooling_conf {
>>   struct thermal_sensor_conf {
>>         char name[SENSOR_NAME_LEN];
>>         int (*read_temperature)(void *data);
>> +       int (*write_emul_temp)(void *drv_data, unsigned long temp);
>
>
> I dont get why you  need a private callback to do this, assuming you have
> only one sensor_conf for exynos.
Actually It is done in this way to keep sensor related stuffs and
common thermal zone related parts. With this it is easy to split this
file in later patches.
>
>
>>         struct thermal_trip_point_conf trip_data;
>>         struct thermal_cooling_conf cooling_data;
>>         void *private_data;
>> @@ -369,6 +370,23 @@ static int exynos_get_temp(struct thermal_zone_device
>> *thermal,
>>         return 0;
>>   }
>>
>> +/* Get temperature callback functions for thermal zone */
>> +static int exynos_set_emul_temp(struct thermal_zone_device *thermal,
>> +                                               unsigned long temp)
>> +{
>> +       void *data;
>> +       int ret = -EINVAL;
>
>
> In case you still want to keep your private callback, Id say -ENOTSUPP is
> better for the case you dont have the callback.
Ok
>
>
>> +
>> +       if (!th_zone->sensor_conf) {
>> +               pr_info("Temperature sensor not initialised\n");
>> +               return -EINVAL;
>> +       }
>> +       data = th_zone->sensor_conf->private_data;
>> +       if (th_zone->sensor_conf->write_emul_temp)
>> +               ret = th_zone->sensor_conf->write_emul_temp(data, temp);
>
>
> nip: a blank line.
>
>
>> +       return ret;
>> +}
>> +
>>   /* Get the temperature trend */
>>   static int exynos_get_trend(struct thermal_zone_device *thermal,
>>                         int trip, enum thermal_trend *trend)
>> @@ -392,6 +410,7 @@ static struct thermal_zone_device_ops const
>> exynos_dev_ops = {
>>         .bind = exynos_bind,
>>         .unbind = exynos_unbind,
>>         .get_temp = exynos_get_temp,
>> +       .set_emul_temp = exynos_set_emul_temp,
>>         .get_trend = exynos_get_trend,
>>         .get_mode = exynos_get_mode,
>>         .set_mode = exynos_set_mode,
>> @@ -714,6 +733,47 @@ static int exynos_tmu_read(struct exynos_tmu_data
>> *data)
>>         return temp;
>>   }
>>
>> +#ifdef CONFIG_THERMAL_EMULATION
>>
>
> I think your code looks cleaner if you move the defines at the beginning of
> your patch to this point.
>
Ok
>
> +static int exynos_tmu_set_emulation(void *drv_data, unsigned long temp)
>>
>> +{
>> +       struct exynos_tmu_data *data = drv_data;
>> +       unsigned int reg;
>> +       int ret = -EINVAL;
>> +
>> +       if (data->soc == SOC_ARCH_EXYNOS4210)
>> +               goto out;
>> +
>
>
> Can you resolve this by not defining this callback for the
> SOC_ARCH_EXYNOS4210 thermal zone ops?
ok.
>
>
>
>> +       if (temp && temp < MCELSIUS)
>> +               goto out;
>> +
>> +       mutex_lock(&data->lock);
>> +       clk_enable(data->clk);
>> +
>> +       reg = readl(data->base + EXYNOS_EMUL_CON);
>> +
>> +       if (temp) {
>> +               temp /= MCELSIUS;
>> +
>> +               reg = (EXYNOS_EMUL_TIME << EXYNOS_EMUL_TIME_SHIFT) |
>> +                       (temp_to_code(data, temp)
>> +                        << EXYNOS_EMUL_DATA_SHIFT) | EXYNOS_EMUL_ENABLE;
>> +       } else {
>> +               reg &= ~EXYNOS_EMUL_ENABLE;
>> +       }
>> +
>> +       writel(reg, data->base + EXYNOS_EMUL_CON);
>> +
>> +       clk_disable(data->clk);
>> +       mutex_unlock(&data->lock);
>
>
> nip: blank line.
>
>
>> +       return 0;
>> +out:
>> +       return ret;
>> +}
>> +#else
>> +static int exynos_tmu_set_emulation(void *drv_data,    unsigned long
>> temp)
>
> unnecessary space                                     |
>
>> +       { return -EINVAL; }
>
>
> I believe if you do a static inline function return 0, the compiler should
> translate it into a nope.
ok will check this.
>
>
>> +#endif/*CONFIG_THERMAL_EMULATION*/
>> +
>>   static void exynos_tmu_work(struct work_struct *work)
>>   {
>>         struct exynos_tmu_data *data = container_of(work,
>> @@ -747,6 +807,7 @@ static irqreturn_t exynos_tmu_irq(int irq, void *id)
>>   static struct thermal_sensor_conf exynos_sensor_conf = {
>>         .name                   = "exynos-therm",
>>         .read_temperature       = (int (*)(void *))exynos_tmu_read,
>> +       .write_emul_temp        = exynos_tmu_set_emulation,
>>   };
>>
>>   #if defined(CONFIG_CPU_EXYNOS4210)
>> @@ -853,93 +914,6 @@ static inline struct  exynos_tmu_platform_data
>> *exynos_get_driver_data(
>>                         platform_get_device_id(pdev)->driver_data;
>>   }
>>
>> -#ifdef CONFIG_EXYNOS_THERMAL_EMUL
>> -static ssize_t exynos_tmu_emulation_show(struct device *dev,
>> -                                        struct device_attribute *attr,
>> -                                        char *buf)
>> -{
>> -       struct platform_device *pdev = container_of(dev,
>> -                                       struct platform_device, dev);
>> -       struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>> -       unsigned int reg;
>> -       u8 temp_code;
>> -       int temp = 0;
>> -
>> -       if (data->soc == SOC_ARCH_EXYNOS4210)
>> -               goto out;
>> -
>> -       mutex_lock(&data->lock);
>> -       clk_enable(data->clk);
>> -       reg = readl(data->base + EXYNOS_EMUL_CON);
>> -       clk_disable(data->clk);
>> -       mutex_unlock(&data->lock);
>> -
>> -       if (reg & EXYNOS_EMUL_ENABLE) {
>> -               reg >>= EXYNOS_EMUL_DATA_SHIFT;
>> -               temp_code = reg & EXYNOS_EMUL_DATA_MASK;
>> -               temp = code_to_temp(data, temp_code);
>> -       }
>> -out:
>> -       return sprintf(buf, "%d\n", temp * MCELSIUS);
>> -}
>> -
>> -static ssize_t exynos_tmu_emulation_store(struct device *dev,
>> -                                       struct device_attribute *attr,
>> -                                       const char *buf, size_t count)
>> -{
>> -       struct platform_device *pdev = container_of(dev,
>> -                                       struct platform_device, dev);
>> -       struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>> -       unsigned int reg;
>> -       int temp;
>> -
>> -       if (data->soc == SOC_ARCH_EXYNOS4210)
>> -               goto out;
>> -
>> -       if (!sscanf(buf, "%d\n", &temp) || temp < 0)
>> -               return -EINVAL;
>> -
>> -       mutex_lock(&data->lock);
>> -       clk_enable(data->clk);
>> -
>> -       reg = readl(data->base + EXYNOS_EMUL_CON);
>> -
>> -       if (temp) {
>> -               /* Both CELSIUS and MCELSIUS type are available for input
>> */
>> -               if (temp > MCELSIUS)
>> -                       temp /= MCELSIUS;
>> -
>> -               reg = (EXYNOS_EMUL_TIME << EXYNOS_EMUL_TIME_SHIFT) |
>> -                       (temp_to_code(data, (temp / MCELSIUS))
>> -                        << EXYNOS_EMUL_DATA_SHIFT) | EXYNOS_EMUL_ENABLE;
>> -       } else {
>> -               reg &= ~EXYNOS_EMUL_ENABLE;
>> -       }
>> -
>> -       writel(reg, data->base + EXYNOS_EMUL_CON);
>> -
>> -       clk_disable(data->clk);
>> -       mutex_unlock(&data->lock);
>> -
>> -out:
>> -       return count;
>> -}
>> -
>> -static DEVICE_ATTR(emulation, 0644, exynos_tmu_emulation_show,
>> -                                       exynos_tmu_emulation_store);
>> -static int create_emulation_sysfs(struct device *dev)
>> -{
>> -       return device_create_file(dev, &dev_attr_emulation);
>> -}
>> -static void remove_emulation_sysfs(struct device *dev)
>> -{
>> -       device_remove_file(dev, &dev_attr_emulation);
>> -}
>> -#else
>> -static inline int create_emulation_sysfs(struct device *dev) { return 0;
>> }
>> -static inline void remove_emulation_sysfs(struct device *dev) {}
>> -#endif
>> -
>>   static int exynos_tmu_probe(struct platform_device *pdev)
>>   {
>>         struct exynos_tmu_data *data;
>> @@ -1039,10 +1013,6 @@ static int exynos_tmu_probe(struct platform_device
>> *pdev)
>>                 goto err_clk;
>>         }
>>
>> -       ret = create_emulation_sysfs(&pdev->dev);
>> -       if (ret)
>> -               dev_err(&pdev->dev, "Failed to create emulation mode sysfs
>> node\n");
>> -
>>         return 0;
>>   err_clk:
>>         platform_set_drvdata(pdev, NULL);
>> @@ -1054,8 +1024,6 @@ static int exynos_tmu_remove(struct platform_device
>> *pdev)
>>   {
>>         struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>>
>> -       remove_emulation_sysfs(&pdev->dev);
>> -
>>         exynos_tmu_control(pdev, false);
>>
>>         exynos_unregister_thermal();
>>
>