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

From: Eduardo Valentin
Date: Thu Apr 11 2013 - 15:34:17 EST

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@xxxxxxxxxxx>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx>

---
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

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.


/* 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.

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.

+
+ 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.

+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?


+ 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.

+#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();


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