Hi Durgadoss, Thanks for the detailed review. On 12 March 2012 16:21, R, Durgadoss <durgadoss.r@xxxxxxxxx> wrote: > Hi Amit, > > Thanks for keeping this up. And Sorry for late reply. > >> -----Original Message----- >> From: amit kachhap [mailto:amitdanielk@xxxxxxxxx] On Behalf Of Amit Daniel >> Kachhap >> Sent: Saturday, March 03, 2012 4:36 PM >> To: linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx >> Cc: linux-kernel@xxxxxxxxxxxxxxx; mjg59@xxxxxxxxxxxxx; linux- >> acpi@xxxxxxxxxxxxxxx; lenb@xxxxxxxxxx; linaro-dev@xxxxxxxxxxxxxxxx; lm- >> sensors@xxxxxxxxxxxxxx; amit.kachhap@xxxxxxxxxx; eduardo.valentin@xxxxxx; R, >> Durgadoss; patches@xxxxxxxxxx >> Subject: [PATCH 1/4] thermal: exynos: Add thermal interface support for linux >> thermal layer >> >> This codes uses the generic linux thermal layer and creates a bridge >> between temperature sensors, linux thermal framework and cooling devices >> for samsung exynos platform. This layer recieves or monitor the >> temperature from the sensor and informs the generic thermal layer to take >> the necessary cooling action. >> >> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@xxxxxxxxxx> >> --- >> drivers/thermal/Kconfig | 8 + >> drivers/thermal/Makefile | 1 + >> drivers/thermal/exynos_thermal.c | 272 ++++++++++++++++++++++++++++++++++++++ >> include/linux/exynos_thermal.h | 72 ++++++++++ >> 4 files changed, 353 insertions(+), 0 deletions(-) >> create mode 100644 drivers/thermal/exynos_thermal.c >> create mode 100644 include/linux/exynos_thermal.h >> >> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig >> index 298c1cd..4e8df56 100644 >> --- a/drivers/thermal/Kconfig >> +++ b/drivers/thermal/Kconfig >> @@ -29,3 +29,11 @@ config CPU_THERMAL >> This will be useful for platforms using the generic thermal interface >> and not the ACPI interface. >> If you want this support, you should say Y or M here. >> + >> +config SAMSUNG_THERMAL_INTERFACE >> + bool "Samsung Thermal interface support" >> + depends on THERMAL && CPU_THERMAL >> + help >> + This is a samsung thermal interface which will be used as >> + a link between sensors and cooling devices with linux thermal >> + framework. >> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile >> index 655cbc4..c67b6b2 100644 >> --- a/drivers/thermal/Makefile >> +++ b/drivers/thermal/Makefile >> @@ -4,3 +4,4 @@ >> >> obj-$(CONFIG_THERMAL) += thermal_sys.o >> obj-$(CONFIG_CPU_THERMAL) += cpu_cooling.o >> +obj-$(CONFIG_SAMSUNG_THERMAL_INTERFACE) += exynos_thermal.o >> diff --git a/drivers/thermal/exynos_thermal.c >> b/drivers/thermal/exynos_thermal.c >> new file mode 100644 >> index 0000000..878d45c >> --- /dev/null >> +++ b/drivers/thermal/exynos_thermal.c >> @@ -0,0 +1,272 @@ >> +/* linux/drivers/thermal/exynos_thermal.c >> + * >> + * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. >> + * http://www.samsung.com >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 as >> + * published by the Free Software Foundation. >> +*/ >> + >> +#include <linux/kernel.h> >> +#include <linux/module.h> >> +#include <linux/thermal.h> >> +#include <linux/platform_device.h> >> +#include <linux/cpufreq.h> >> +#include <linux/err.h> >> +#include <linux/slab.h> >> +#include <linux/cpu_cooling.h> >> +#include <linux/exynos_thermal.h> >> + >> +#define MAX_COOLING_DEVICE 4 >> +struct exynos4_thermal_zone { >> + unsigned int idle_interval; >> + unsigned int active_interval; >> + struct thermal_zone_device *therm_dev; >> + struct thermal_cooling_device *cool_dev[MAX_COOLING_DEVICE]; >> + unsigned int cool_dev_size; >> + struct platform_device *exynos4_dev; >> + struct thermal_sensor_conf *sensor_conf; >> +}; >> + >> +static struct exynos4_thermal_zone *th_zone; >> + >> +static int exynos4_get_mode(struct thermal_zone_device *thermal, >> + enum thermal_device_mode *mode) >> +{ >> + if (th_zone->sensor_conf) { >> + pr_info("Temperature sensor not initialised\n"); >> + *mode = THERMAL_DEVICE_DISABLED; >> + } else >> + *mode = THERMAL_DEVICE_ENABLED; >> + return 0; >> +} >> + >> +static int exynos4_set_mode(struct thermal_zone_device *thermal, >> + enum thermal_device_mode mode) >> +{ >> + if (!th_zone->therm_dev) { >> + pr_notice("thermal zone not registered\n"); >> + return 0; >> + } >> + if (mode == THERMAL_DEVICE_ENABLED) >> + th_zone->therm_dev->polling_delay = >> + th_zone->active_interval*1000; >> + else >> + th_zone->therm_dev->polling_delay = >> + th_zone->idle_interval*1000; > > If it is 'DISABLED' mode, shouldn't the polling delay be just 0 ? Yes Ideally this should be zero. But I wanted thermal monitoring to always happen with some long interval in case of error scenarios. Anyway I will check this again. > >> + >> + thermal_zone_device_update(th_zone->therm_dev); >> + pr_info("thermal polling set for duration=%d sec\n", >> + th_zone->therm_dev->polling_delay/1000); >> + return 0; >> +} >> + >> +/*This may be called from interrupt based temperature sensor*/ >> +void exynos4_report_trigger(void) >> +{ >> + unsigned int monitor_temp; >> + >> + if (!th_zone || !th_zone->therm_dev) >> + return; >> + >> + monitor_temp = th_zone->sensor_conf->trip_data.trip_val[0]; > > Why are we checking only against the 0-th trip point ? > Why not for other trip_val[i] also ? Yes correct. Actually the trip temperatures are arranged in ascending order. > >> + >> + thermal_zone_device_update(th_zone->therm_dev); >> + >> + mutex_lock(&th_zone->therm_dev->lock); >> + if (th_zone->therm_dev->last_temperature > monitor_temp) >> + th_zone->therm_dev->polling_delay = >> + th_zone->active_interval*1000; >> + else >> + th_zone->therm_dev->polling_delay = >> + th_zone->idle_interval*1000; >> + >> + kobject_uevent(&th_zone->therm_dev->device.kobj, KOBJ_CHANGE); > > Wouldn't it make more sense to pass the trip point id also as an 'env' > parameter ? This way, the user space can easily figure out which trip > point has been crossed. Its a good suggestion. I will check if some uevent property allows that. > >> + mutex_unlock(&th_zone->therm_dev->lock); >> +} >> + >> +static int exynos4_get_trip_type(struct thermal_zone_device *thermal, int >> trip, >> + enum thermal_trip_type *type) >> +{ >> + if (trip == 0 || trip == 1) >> + *type = THERMAL_TRIP_STATE_ACTIVE; >> + else if (trip == 2) >> + *type = THERMAL_TRIP_CRITICAL; >> + else >> + return -EINVAL; >> + >> + return 0; >> +} >> + >> +static int exynos4_get_trip_temp(struct thermal_zone_device *thermal, int >> trip, >> + unsigned long *temp) >> +{ >> + /*Monitor zone*/ >> + if (trip == 0) >> + *temp = th_zone->sensor_conf->trip_data.trip_val[0]; >> + /*Warn zone*/ >> + else if (trip == 1) >> + *temp = th_zone->sensor_conf->trip_data.trip_val[1]; >> + /*Panic zone*/ >> + else if (trip == 2) >> + *temp = th_zone->sensor_conf->trip_data.trip_val[2]; >> + else >> + return -EINVAL; >> + /*convert the temperature into millicelsius*/ >> + *temp = *temp * 1000; >> + >> + return 0; >> +} > > This could be: > > if (trip < 0 || trip >2) return -EINVAL; > *temp = th_zone->sensor_conf->trip_data.trip_val[trip]; > return 0; Agreed. Will apply. > >> + >> +static int exynos4_get_crit_temp(struct thermal_zone_device *thermal, >> + unsigned long *temp) >> +{ >> + /*Panic zone*/ >> + *temp = th_zone->sensor_conf->trip_data.trip_val[2]; >> + /*convert the temperature into millicelsius*/ >> + *temp = *temp * 1000; >> + return 0; >> +} > > Why not make it, exynos4_get_trip_temp(thermal, 2, temp) ? OK. > >> + >> +static int exynos4_bind(struct thermal_zone_device *thermal, >> + struct thermal_cooling_device *cdev) >> +{ >> + /* if the cooling device is the one from exynos4 bind it */ >> + if (cdev != th_zone->cool_dev[0]) >> + return 0; >> + >> + if (thermal_zone_bind_cooling_device(thermal, 0, cdev)) { >> + pr_err("error binding cooling dev\n"); >> + return -EINVAL; >> + } >> + if (thermal_zone_bind_cooling_device(thermal, 1, cdev)) { >> + pr_err("error binding cooling dev\n"); >> + return -EINVAL; > > If we fail here, do you want to remove the earlier 'binding' also ? Yes. Missed this error handling. > >> + } >> + >> + return 0; >> + >> +} >> + >> +static int exynos4_unbind(struct thermal_zone_device *thermal, >> + struct thermal_cooling_device *cdev) >> +{ >> + if (cdev != th_zone->cool_dev[0]) >> + return 0; >> + >> + if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) { >> + pr_err("error unbinding cooling dev\n"); >> + return -EINVAL; > > I think we should still go ahead and try to 'unbind' the other one. Yes. Missed this error handling. > >> + } >> + if (thermal_zone_unbind_cooling_device(thermal, 1, cdev)) { >> + pr_err("error unbinding cooling dev\n"); >> + return -EINVAL; >> + } >> + return 0; >> + >> +} >> + >> +static int exynos4_get_temp(struct thermal_zone_device *thermal, >> + unsigned long *temp) >> +{ >> + void *data; >> + >> + if (!th_zone->sensor_conf) { >> + pr_info("Temperature sensor not initialised\n"); >> + return -EINVAL; >> + } >> + data = th_zone->sensor_conf->private_data; >> + *temp = th_zone->sensor_conf->read_temperature(data); >> + /*convert the temperature into millicelsius*/ >> + *temp = *temp * 1000; >> + return 0; >> +} >> + >> +/* bind callback functions to thermalzone */ >> +static struct thermal_zone_device_ops exynos4_dev_ops = { >> + .bind = exynos4_bind, >> + .unbind = exynos4_unbind, >> + .get_temp = exynos4_get_temp, >> + .get_mode = exynos4_get_mode, >> + .set_mode = exynos4_set_mode, >> + .get_trip_type = exynos4_get_trip_type, >> + .get_trip_temp = exynos4_get_trip_temp, >> + .get_crit_temp = exynos4_get_crit_temp, >> +}; >> + >> +int exynos4_register_thermal(struct thermal_sensor_conf *sensor_conf) >> +{ >> + int ret, count, tab_size; >> + struct freq_pctg_table *tab_ptr; >> + >> + if (!sensor_conf || !sensor_conf->read_temperature) { >> + pr_err("Temperature sensor not initialised\n"); >> + return -EINVAL; >> + } >> + >> + th_zone = kzalloc(sizeof(struct exynos4_thermal_zone), GFP_KERNEL); >> + if (!th_zone) { >> + ret = -ENOMEM; >> + goto err_unregister; >> + } >> + >> + th_zone->sensor_conf = sensor_conf; >> + >> + tab_ptr = (struct freq_pctg_table *)sensor_conf->cooling_data.freq_data; >> + tab_size = sensor_conf->cooling_data.freq_pctg_count; >> + >> + /*Register the cpufreq cooling device*/ >> + th_zone->cool_dev_size = 1; >> + count = 0; >> + th_zone->cool_dev[count] = cpufreq_cooling_register( >> + (struct freq_pctg_table *)&(tab_ptr[count]), >> + tab_size, cpumask_of(0)); >> + >> + if (IS_ERR(th_zone->cool_dev[count])) { >> + pr_err("Failed to register cpufreq cooling device\n"); >> + ret = -EINVAL; >> + th_zone->cool_dev_size = 0; >> + goto err_unregister; >> + } >> + >> + th_zone->therm_dev = thermal_zone_device_register(sensor_conf->name, >> + 3, NULL, &exynos4_dev_ops, 0, 0, 0, 1000); >> + if (IS_ERR(th_zone->therm_dev)) { >> + pr_err("Failed to register thermal zone device\n"); >> + ret = -EINVAL; >> + goto err_unregister; >> + } >> + >> + th_zone->active_interval = 1; >> + th_zone->idle_interval = 10; >> + >> + exynos4_set_mode(th_zone->therm_dev, THERMAL_DEVICE_DISABLED); >> + >> + pr_info("Exynos: Kernel Thermal management registered\n"); >> + >> + return 0; >> + >> +err_unregister: >> + exynos4_unregister_thermal(); >> + return ret; >> +} >> +EXPORT_SYMBOL(exynos4_register_thermal); >> + >> +void exynos4_unregister_thermal(void) >> +{ >> + unsigned int i; >> + >> + for (i = 0; i < th_zone->cool_dev_size; i++) { >> + if (th_zone && th_zone->cool_dev[i]) >> + cpufreq_cooling_unregister(th_zone->cool_dev[i]); >> + } >> + >> + if (th_zone && th_zone->therm_dev) >> + thermal_zone_device_unregister(th_zone->therm_dev); >> + >> + kfree(th_zone); >> + >> + pr_info("Exynos: Kernel Thermal management unregistered\n"); >> +} >> +EXPORT_SYMBOL(exynos4_unregister_thermal); >> diff --git a/include/linux/exynos_thermal.h b/include/linux/exynos_thermal.h >> new file mode 100644 >> index 0000000..186e409 >> --- /dev/null >> +++ b/include/linux/exynos_thermal.h >> @@ -0,0 +1,72 @@ >> +/* linux/include/linux/exynos_thermal.h >> + * >> + * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. >> + * http://www.samsung.com >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 as >> + * published by the Free Software Foundation. >> +*/ >> + >> +#ifndef THERMAL_INTERFACE_H >> +#define THERMAL_INTERFACE_H >> +/* CPU Zone information */ >> + >> +#define SENSOR_NAME_LEN 16 >> +#define MAX_TRIP_COUNT 8 >> + >> +#define PANIC_ZONE 4 >> +#define WARN_ZONE 3 >> +#define MONITOR_ZONE 2 >> +#define SAFE_ZONE 1 >> +#define NO_ACTION 0 > > I don't get why we need two separate SAFE and NO_ACTION > zones..To me, both should be the same. Yes not needed. > >> + >> + >> +struct thermal_trip_point_conf { >> + int trip_val[MAX_TRIP_COUNT]; >> + int trip_count; >> +}; >> + >> +struct thermal_cooling_conf { >> + struct freq_pctg_table freq_data[MAX_TRIP_COUNT]; >> + int freq_pctg_count; >> +}; >> + >> +/** >> + * struct exynos4_tmu_platform_data >> + * @name: name of the temperature sensor >> + * @read_temperature: A function pointer to read temperature info >> + * @private_data: Temperature sensor private data >> + * @sensor_data: Sensor specific information like trigger temperature, level >> + */ >> +struct thermal_sensor_conf { >> + char name[SENSOR_NAME_LEN]; >> + int (*read_temperature)(void *data); >> + struct thermal_trip_point_conf trip_data; >> + struct thermal_cooling_conf cooling_data; > > Since both trip_count and freq_pctg_count are same at all > times (please correct me if I am wrong) I think it's better > to have a single 'count' variable inside this structure and move > trip_val and freq_data to this structure directly. No trip_count and pctg_count are different. > > One General Concern: > Why do we even need this exynos_thermal layer between Thermal Framework > and the Thermal Sensor Drivers ? I think the thermal sensor driver (in > this case exynos_tmu.c) can directly register with the Thermal framework. > This means, we will soon have platformXXX_thermal.c files for each > platform, which is not really a good way to go IMHO. > I also understand that the framework does not have alarm attributes, > notification support etc..But We can add them if needed. Yes even comments from Guenter Roeck and Mark Brown also point in the same direction. Actually I wanted to separate the sensor h/w implementation independent from thermal management algorithm so its future modification may be clean. But looks like the agreement is to merge them. > > I have reviewed your two sets of patches independently. My only > request to you would be to post the next versions of both the patch > sets at the same time, so that it becomes easier to understand and test. Thanks even i also think this a good way. > > Thanks, > Durga > >> + void *private_data; >> +}; >> + >> +/** >> + * exynos4_register_thermal: Register to the exynos thermal interface. >> + * @sensor_conf: Structure containing temperature sensor information >> + * >> + * returns zero on success, else negative errno. >> + */ >> +int exynos4_register_thermal(struct thermal_sensor_conf *sensor_conf); >> + >> +/** >> + * exynos4_unregister_thermal: Un-register from the exynos thermal interface. >> + * >> + * return not applicable. >> + */ >> +void exynos4_unregister_thermal(void); >> + >> +/** >> + * exynos4_report_trigger: Report any trigger level crossed in the >> + * temperature sensor. This may be useful to take any cooling action. >> + * >> + * return not applicable. >> + */ >> +extern void exynos4_report_trigger(void); >> +#endif >> -- >> 1.7.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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