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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Zhang Rui <rui.zhang@intel.com>
Cc: linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org,
	Matthew Garrett <mjg@redhat.com>, Len Brown <lenb@kernel.org>,
	R Durgadoss <durgadoss.r@intel.com>,
	Eduardo Valentin <eduardo.valentin@intel.com>,
	Amit Kachhap <amit.kachhap@linaro.org>, Wei Ni <wni@nvidia.com>
Subject: Re: [PATCH 01/16] Thermal: Make Thermal trip points writeable
Date: Thu, 19 Jul 2012 22:27:13 +0200	[thread overview]
Message-ID: <201207192227.13357.rjw@sisk.pl> (raw)
In-Reply-To: <1342679480-5336-2-git-send-email-rui.zhang@intel.com>

On Thursday, July 19, 2012, Zhang Rui wrote:
> From: Durgadoss R <dugardoss.r@intel.com>
> 
> Some of the thermal drivers using the Generic Thermal Framework
> require (all/some) trip points to be writeable. This patch makes
> the trip point temperatures writeable on a per-trip point basis,
> and modifies the required function call in thermal.c. This patch
> also updates the Documentation to reflect the new change.
> 
> Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> ---
>  Documentation/thermal/sysfs-api.txt      |    4 +-
>  drivers/acpi/thermal.c                   |    4 +-
>  drivers/platform/x86/acerhdf.c           |    2 +-
>  drivers/platform/x86/intel_mid_thermal.c |    2 +-
>  drivers/thermal/spear_thermal.c          |    2 +-
>  drivers/thermal/thermal_sys.c            |  147 +++++++++++++++++++++---------
>  include/linux/thermal.h                  |   15 ++-
>  7 files changed, 125 insertions(+), 51 deletions(-)
> 
> diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
> index 1733ab9..0c7c423 100644
> --- a/Documentation/thermal/sysfs-api.txt
> +++ b/Documentation/thermal/sysfs-api.txt
> @@ -32,7 +32,8 @@ temperature) and throttle appropriate devices.
>  
>  1.1 thermal zone device interface
>  1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *name,
> -		int trips, void *devdata, struct thermal_zone_device_ops *ops)
> +		int trips, int flag, void *devdata,

The 'flags' argument should rather be called 'mask', or even 'writable_mask'.

> +		struct thermal_zone_device_ops *ops)
>  
>      This interface function adds a new thermal zone device (sensor) to
>      /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
> @@ -40,6 +41,7 @@ temperature) and throttle appropriate devices.
>  
>      name: the thermal zone name.
>      trips: the total number of trip points this thermal zone supports.
> +    flag: Bit string: If 'n'th bit is set, then trip point 'n' is writeable.
>      devdata: device private data
>      ops: thermal zone device call-backs.
>  	.bind: bind the thermal zone device with a thermal cooling device.
> diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
> index 7dbebea..2107d1b 100644
> --- a/drivers/acpi/thermal.c
> +++ b/drivers/acpi/thermal.c
> @@ -845,7 +845,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>  
>  	if (tz->trips.passive.flags.valid)
>  		tz->thermal_zone =
> -			thermal_zone_device_register("acpitz", trips, tz,
> +			thermal_zone_device_register("acpitz", trips, 0, tz,
>  						     &acpi_thermal_zone_ops,
>  						     tz->trips.passive.tc1,
>  						     tz->trips.passive.tc2,
> @@ -853,7 +853,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>  						     tz->polling_frequency*100);
>  	else
>  		tz->thermal_zone =
> -			thermal_zone_device_register("acpitz", trips, tz,
> +			thermal_zone_device_register("acpitz", trips, 0, tz,
>  						     &acpi_thermal_zone_ops,
>  						     0, 0, 0,
>  						     tz->polling_frequency*100);
> diff --git a/drivers/platform/x86/acerhdf.c b/drivers/platform/x86/acerhdf.c
> index 2fd9d36..39abb15 100644
> --- a/drivers/platform/x86/acerhdf.c
> +++ b/drivers/platform/x86/acerhdf.c
> @@ -660,7 +660,7 @@ static int acerhdf_register_thermal(void)
>  	if (IS_ERR(cl_dev))
>  		return -EINVAL;
>  
> -	thz_dev = thermal_zone_device_register("acerhdf", 1, NULL,
> +	thz_dev = thermal_zone_device_register("acerhdf", 1, 0, NULL,
>  					      &acerhdf_dev_ops, 0, 0, 0,
>  					      (kernelmode) ? interval*1000 : 0);
>  	if (IS_ERR(thz_dev))
> diff --git a/drivers/platform/x86/intel_mid_thermal.c b/drivers/platform/x86/intel_mid_thermal.c
> index 5ae9cd9..2b2c212 100644
> --- a/drivers/platform/x86/intel_mid_thermal.c
> +++ b/drivers/platform/x86/intel_mid_thermal.c
> @@ -499,7 +499,7 @@ static int mid_thermal_probe(struct platform_device *pdev)
>  			goto err;
>  		}
>  		pinfo->tzd[i] = thermal_zone_device_register(name[i],
> -				0, td_info, &tzd_ops, 0, 0, 0, 0);
> +				0, 0, td_info, &tzd_ops, 0, 0, 0, 0);
>  		if (IS_ERR(pinfo->tzd[i])) {
>  			kfree(td_info);
>  			ret = PTR_ERR(pinfo->tzd[i]);
> diff --git a/drivers/thermal/spear_thermal.c b/drivers/thermal/spear_thermal.c
> index c2e32df..69a55d4 100644
> --- a/drivers/thermal/spear_thermal.c
> +++ b/drivers/thermal/spear_thermal.c
> @@ -147,7 +147,7 @@ static int spear_thermal_probe(struct platform_device *pdev)
>  	stdev->flags = pdata->thermal_flags;
>  	writel_relaxed(stdev->flags, stdev->thermal_base);
>  
> -	spear_thermal = thermal_zone_device_register("spear_thermal", 0,
> +	spear_thermal = thermal_zone_device_register("spear_thermal", 0, 0,
>  				stdev, &ops, 0, 0, 0, 0);
>  	if (IS_ERR(spear_thermal)) {
>  		dev_err(&pdev->dev, "thermal zone device is NULL\n");
> diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
> index 022bacb..a590d57 100644
> --- a/drivers/thermal/thermal_sys.c
> +++ b/drivers/thermal/thermal_sys.c
> @@ -196,6 +196,28 @@ trip_point_type_show(struct device *dev, struct device_attribute *attr,
>  }
>  
>  static ssize_t
> +trip_point_temp_store(struct device *dev, struct device_attribute *attr,
> +		     const char *buf, size_t count)
> +{
> +	struct thermal_zone_device *tz = to_thermal_zone(dev);
> +	int trip, ret;
> +	unsigned long temperature;
> +
> +	if (!tz->ops->set_trip_temp)
> +		return -EPERM;
> +
> +	if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
> +		return -EINVAL;
> +
> +	if (kstrtoul(buf, 10, &temperature))
> +		return -EINVAL;
> +
> +	ret = tz->ops->set_trip_temp(tz, trip, temperature);
> +
> +	return ret ? ret : count;
> +}
> +
> +static ssize_t
>  trip_point_temp_show(struct device *dev, struct device_attribute *attr,
>  		     char *buf)
>  {
> @@ -283,33 +305,6 @@ static DEVICE_ATTR(temp, 0444, temp_show, NULL);
>  static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
>  static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, passive_store);
>  
> -static struct device_attribute trip_point_attrs[] = {
> -	__ATTR(trip_point_0_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_0_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_1_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_1_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_2_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_2_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_3_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_3_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_4_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_4_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_5_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_5_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_6_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_6_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_7_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_7_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_8_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_8_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_9_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_9_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_10_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_10_temp, 0444, trip_point_temp_show, NULL),
> -	__ATTR(trip_point_11_type, 0444, trip_point_type_show, NULL),
> -	__ATTR(trip_point_11_temp, 0444, trip_point_temp_show, NULL),
> -};
> -
>  /* sys I/F for cooling device */
>  #define to_cooling_device(_dev)	\
>  	container_of(_dev, struct thermal_cooling_device, device)
> @@ -1089,9 +1084,83 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
>  EXPORT_SYMBOL(thermal_zone_device_update);
>  
>  /**
> + * create_trip_attrs - create attributes for trip points
> + * @tz:		the thermal zone device
> + * @flag:	Writeable trip point bitmap.
> + */
> +static int create_trip_attrs(struct thermal_zone_device *tz, int flag)
> +{
> +	int indx;
> +	int writeable;
> +
> +	tz->trip_type_attrs =
> +		kzalloc(sizeof(struct thermal_attr) * tz->trips, GFP_KERNEL);
> +	if (!tz->trip_type_attrs)
> +		return -ENOMEM;
> +
> +	tz->trip_temp_attrs =
> +		kzalloc(sizeof(struct thermal_attr) * tz->trips, GFP_KERNEL);
> +	if (!tz->trip_temp_attrs) {
> +		kfree(tz->trip_type_attrs);
> +		return -ENOMEM;
> +	}
> +
> +	for (indx = 0; indx < tz->trips; indx++) {
> +
> +		/* create trip type attribute */
> +		snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
> +			 "trip_point_%d_type", indx);

If this really truncates the name, we'll run into problems in _show() and _store().
Is there any solution to that?

> +
> +		sysfs_attr_init(&tz->trip_type_attrs[count].attr.attr);
> +		tz->trip_type_attrs[indx].attr.attr.name =
> +						tz->trip_type_attrs[indx].name;
> +		tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
> +		tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
> +
> +		device_create_file(&tz->device,
> +				   &tz->trip_type_attrs[indx].attr);
> +
> +		/* create trip temp attribute */
> +		writeable = flag & (1 << indx);
> +		snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
> +			 "trip_point_%d_temp", indx);
> +
> +		sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
> +		tz->trip_temp_attrs[indx].attr.attr.name =
> +						tz->trip_temp_attrs[indx].name;
> +		tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
> +		tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
> +		if (writeable) {

Why don't you put the "flag & (1 << indx)" here directly instead of 'writable'?

> +			tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
> +			tz->trip_temp_attrs[indx].attr.store =
> +							trip_point_temp_store;
> +		}
> +
> +		device_create_file(&tz->device,
> +				   &tz->trip_temp_attrs[indx].attr);
> +	}
> +	return 0;
> +}
> +
> +static void remove_trip_attrs(struct thermal_zone_device *tz)
> +{
> +	int indx;
> +
> +	for (indx = 0; indx < tz->trips; indx++) {
> +		device_remove_file(&tz->device,
> +				   &tz->trip_type_attrs[indx].attr);
> +		device_remove_file(&tz->device,
> +				   &tz->trip_temp_attrs[indx].attr);
> +	}
> +	kfree(tz->trip_type_attrs);
> +	kfree(tz->trip_temp_attrs);
> +}
> +
> +/**
>   * thermal_zone_device_register - register a new thermal zone device
>   * @type:	the thermal zone device type
>   * @trips:	the number of trip points the thermal zone support
> + * @flag:	a bit string indicating the writeablility of trip points
>   * @devdata:	private device data
>   * @ops:	standard thermal zone device callbacks
>   * @tc1:	thermal coefficient 1 for passive calculations
> @@ -1107,7 +1176,7 @@ EXPORT_SYMBOL(thermal_zone_device_update);
>   * section 11.1.5.1 of the ACPI specification 3.0.
>   */
>  struct thermal_zone_device *thermal_zone_device_register(char *type,
> -	int trips, void *devdata,
> +	int trips, int flag, void *devdata,
>  	const struct thermal_zone_device_ops *ops,
>  	int tc1, int tc2, int passive_delay, int polling_delay)
>  {
> @@ -1124,6 +1193,9 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
>  	if (trips > THERMAL_MAX_TRIPS || trips < 0)
>  		return ERR_PTR(-EINVAL);
>  
> +	if (flag >> trips)
> +		return ERR_PTR(-EINVAL);

I'm not sure if this check is necessary.  Does it actually matter is someone
passes ones in the unused bit positions?

> +
>  	if (!ops || !ops->get_temp)
>  		return ERR_PTR(-EINVAL);
>  
> @@ -1175,15 +1247,11 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
>  			goto unregister;
>  	}
>  
> +	result = create_trip_attrs(tz, flag);
> +	if (result)
> +		goto unregister;
> +
>  	for (count = 0; count < trips; count++) {
> -		result = device_create_file(&tz->device,
> -					    &trip_point_attrs[count * 2]);
> -		if (result)
> -			break;
> -		result = device_create_file(&tz->device,
> -					    &trip_point_attrs[count * 2 + 1]);
> -		if (result)
> -			goto unregister;
>  		tz->ops->get_trip_type(tz, count, &trip_type);
>  		if (trip_type == THERMAL_TRIP_PASSIVE)
>  			passive = 1;
> @@ -1259,13 +1327,8 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz)
>  	device_remove_file(&tz->device, &dev_attr_temp);
>  	if (tz->ops->get_mode)
>  		device_remove_file(&tz->device, &dev_attr_mode);
> +	remove_trip_attrs(tz);
>  
> -	for (count = 0; count < tz->trips; count++) {
> -		device_remove_file(&tz->device,
> -				   &trip_point_attrs[count * 2]);
> -		device_remove_file(&tz->device,
> -				   &trip_point_attrs[count * 2 + 1]);
> -	}
>  	thermal_remove_hwmon_sysfs(tz);
>  	release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
>  	idr_destroy(&tz->idr);
> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
> index 796f1ff..6eaf914 100644
> --- a/include/linux/thermal.h
> +++ b/include/linux/thermal.h
> @@ -58,6 +58,8 @@ struct thermal_zone_device_ops {
>  		enum thermal_trip_type *);
>  	int (*get_trip_temp) (struct thermal_zone_device *, int,
>  			      unsigned long *);
> +	int (*set_trip_temp) (struct thermal_zone_device *, int,
> +			      unsigned long);
>  	int (*get_crit_temp) (struct thermal_zone_device *, unsigned long *);
>  	int (*notify) (struct thermal_zone_device *, int,
>  		       enum thermal_trip_type);
> @@ -85,10 +87,17 @@ struct thermal_cooling_device {
>  				((long)t-2732+5)/10 : ((long)t-2732-5)/10)
>  #define CELSIUS_TO_KELVIN(t)	((t)*10+2732)
>  
> +struct thermal_attr {
> +	struct device_attribute attr;
> +	char name[THERMAL_NAME_LENGTH];
> +};
> +
>  struct thermal_zone_device {
>  	int id;
>  	char type[THERMAL_NAME_LENGTH];
>  	struct device device;
> +	struct thermal_attr *trip_temp_attrs;
> +	struct thermal_attr *trip_type_attrs;
>  	void *devdata;
>  	int trips;
>  	int tc1;
> @@ -137,9 +146,9 @@ enum {
>  };
>  #define THERMAL_GENL_CMD_MAX (__THERMAL_GENL_CMD_MAX - 1)
>  
> -struct thermal_zone_device *thermal_zone_device_register(char *, int, void *,
> -		const struct thermal_zone_device_ops *, int tc1, int tc2,
> -		int passive_freq, int polling_freq);
> +struct thermal_zone_device *thermal_zone_device_register(char *, int, int,
> +		void *, const struct thermal_zone_device_ops *, int tc1,
> +		int tc2, int passive_freq, int polling_freq);
>  void thermal_zone_device_unregister(struct thermal_zone_device *);
>  
>  int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
> 

Thanks,
Rafael

  parent reply	other threads:[~2012-07-19 20:21 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-07-19  6:31 [PATCH 00/16] Thermal: generic thermal layer enhancement Zhang Rui
2012-07-19  6:31 ` [PATCH 01/16] Thermal: Make Thermal trip points writeable Zhang Rui
2012-07-19 10:35   ` R, Durgadoss
2012-07-19 19:38   ` Rafael J. Wysocki
2012-07-23  8:11     ` Zhang Rui
2012-07-19 20:27   ` Rafael J. Wysocki [this message]
2012-07-23  8:22     ` Zhang Rui
2012-07-23 10:25       ` Rafael J. Wysocki
2012-07-19  6:31 ` [PATCH 02/16] Thermal: Add Hysteresis attributes Zhang Rui
2012-07-19 10:40   ` R, Durgadoss
2012-07-19 20:00     ` Rafael J. Wysocki
2012-07-19  6:31 ` [PATCH 03/16] Thermal: Documentation update Zhang Rui
2012-07-19 10:51   ` R, Durgadoss
2012-07-23  8:36     ` Zhang Rui
2012-07-19  6:31 ` [PATCH 04/16] Thermal: Introduce multiple cooling states support Zhang Rui
2012-07-19  6:31 ` [PATCH 05/16] Thermal: Introduce cooling states range support Zhang Rui
2012-07-19  6:31 ` [PATCH 06/16] Thermal: set upper and lower limits Zhang Rui
2012-07-19 20:55   ` Rafael J. Wysocki
2012-07-23  8:45     ` Zhang Rui
2012-07-23 19:15       ` Rafael J. Wysocki
2012-07-19  6:31 ` [PATCH 07/16] Thermal: Introduce .get_trend() callback Zhang Rui
2012-07-19 21:13   ` Rafael J. Wysocki
2012-07-24  1:42     ` Zhang Rui
2012-07-24  9:22       ` Rafael J. Wysocki
2012-07-19 22:09   ` Jacob Pan
2012-07-20  9:53     ` Rafael J. Wysocki
2012-07-20 16:12       ` Jacob Pan
2012-07-19  6:31 ` [PATCH 08/16] Thermal: Remove tc1/tc2 in generic thermal layer Zhang Rui
2012-07-19  6:31 ` [PATCH 09/16] Thermal: Introduce thermal_zone_trip_update() Zhang Rui
2012-07-19 21:19   ` Rafael J. Wysocki
2012-07-24  1:47     ` Zhang Rui
2012-07-24  9:27       ` Rafael J. Wysocki
2012-07-25  1:38         ` Zhang Rui
2012-07-25 11:07           ` Rafael J. Wysocki
2012-07-26  0:49             ` Zhang Rui
     [not found]   ` <CAK44p21hNYGH4YkH5E+XK-pM2upingQbvm77WkJbttCRp6ZamQ@mail.gmail.com>
2012-07-24  7:11     ` Zhang Rui
2012-07-24  8:06       ` Amit Kachhap
2012-07-26  5:08         ` Zhang Rui
2012-07-26  6:01           ` R, Durgadoss
2012-07-24  7:57   ` Amit Kachhap
2012-07-19  6:31 ` [PATCH 10/16] Thermal: rename structure thermal_cooling_device_instance to thermal_instance Zhang Rui
2012-07-19  6:31 ` [PATCH 11/16] Thermal: Rename thermal_zone_device.cooling_devices to thermal_zone_device.instances Zhang Rui
2012-07-19 21:22   ` Rafael J. Wysocki
2012-07-24  1:48     ` Zhang Rui
2012-07-19  6:31 ` [PATCH 12/16] Thermal: Rename thermal_instance.node to thermal_instance.tz_node Zhang Rui
2012-07-19  6:31 ` [PATCH 13/16] Thermal: List thermal_instance in thermal_cooling_device Zhang Rui
2012-07-19 21:25   ` Rafael J. Wysocki
2012-07-24  1:48     ` Zhang Rui
2012-07-19  6:31 ` [PATCH 14/16] Thermal: Introduce simple arbitrator for setting device cooling state Zhang Rui
2012-07-19 21:39   ` Rafael J. Wysocki
2012-07-24  1:49     ` Zhang Rui
2012-07-19  6:31 ` [PATCH 15/16] Thermal: Unify the code for both active and passive cooling Zhang Rui
2012-07-19  6:31 ` [PATCH 16/16] Thermal: use plist instead of list Zhang Rui
2012-07-19 21:45   ` Rafael J. Wysocki
2012-07-24  2:13     ` Zhang Rui
2012-07-19  6:37 ` [PATCH 00/16] Thermal: generic thermal layer enhancement Zhang Rui

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