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Date:	Mon, 08 Dec 2014 11:35:02 +0800
From:	Zhang Rui <rui.zhang@...el.com>
To:	Aaron Lu <aaron.lu@...el.com>
Cc:	Eduardo Valentin <edubezval@...il.com>,
	Jim Davis <jim.epost@...il.com>,
	Stephen Rothwell <sfr@...b.auug.org.au>,
	linux-next <linux-next@...r.kernel.org>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	linux-pm@...r.kernel.org
Subject: Re: [PATCH] Thermal: introduce INT3406 thermal driver

On Tue, 2014-12-02 at 14:18 +0800, Aaron Lu wrote:
> On 11/30/2014 08:22 PM, Zhang Rui wrote:
> > On Fri, 2014-11-07 at 15:11 -0400, Eduardo Valentin wrote:
> >> Hi,
> >>
> >> On Tue, Oct 28, 2014 at 02:11:59PM +0800, Aaron Lu wrote:
> >>> Jim found that the current kernel may trigger a build error with some
> >>> config: drivers/built-in.o: In function `int3406_thermal_probe':
> >>> int3406_thermal.c:(.text+0x1d10b8): undefined reference to
> >>> `acpi_video_get_levels'. The problem happens when CONFIG_THERMAL=y and
> >>> CONFIG_ACPI_VIDEO=m. Solve the problem by separating a kernel config for
> >>> int3406 thermal driver and add dependency on ACPI video for it.
> >>>
> >>> Reported-by: Jim Davis <jim.epost@...il.com>
> >>> Signed-off-by: Aaron Lu <aaron.lu@...el.com>
> >>
> > Aaron, this is an incremental patch on top of the INT3406 driver patch.
> > As, both patches have not been shipped in Linus' tree, please merge
> > these two patches altogether and resend.
> 
> OK, here it is:
> 
> From 02d7abdcfe138e6cdee7572b10addce4f56d89eb Mon Sep 17 00:00:00 2001
> From: Aaron Lu <aaron.lu@...el.com>
> Date: Wed, 3 Sep 2014 15:15:02 +0800
> Subject: [PATCH] Thermal: introduce INT3406 thermal driver
> 
> INT3406 ACPI device object resembles an ACPI video output device, but its
> _BCM is said to be deprecated and should not be used. So we will make
> use of the raw interface to do the actual cooling. Due to this, the
> backlight core has some modifications. Also, to re-use some of the ACPI
> video module's code, one function has been exported.
> 
> Signed-off-by: Aaron Lu <aaron.lu@...el.com>
> Signed-off-by: Zhang Rui <rui.zhang@...el.com>

applied.

thanks,
rui
> ---
>  drivers/acpi/video.c                              |  78 ++++----
>  drivers/thermal/Kconfig                           |  26 +--
>  drivers/thermal/int340x_thermal/Makefile          |   1 +
>  drivers/thermal/int340x_thermal/int3406_thermal.c | 230 ++++++++++++++++++++++
>  drivers/video/backlight/backlight.c               |  44 +++--
>  include/acpi/video.h                              |  20 ++
>  include/linux/backlight.h                         |   2 +
>  7 files changed, 326 insertions(+), 75 deletions(-)
>  create mode 100644 drivers/thermal/int340x_thermal/int3406_thermal.c
> 
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index 826884392e6b..b2604322dd1f 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -186,19 +186,6 @@ struct acpi_video_device_cap {
>  	u8 _DDC:1;		/* Return the EDID for this device */
>  };
>  
> -struct acpi_video_brightness_flags {
> -	u8 _BCL_no_ac_battery_levels:1;	/* no AC/Battery levels in _BCL */
> -	u8 _BCL_reversed:1;		/* _BCL package is in a reversed order */
> -	u8 _BQC_use_index:1;		/* _BQC returns an index value */
> -};
> -
> -struct acpi_video_device_brightness {
> -	int curr;
> -	int count;
> -	int *levels;
> -	struct acpi_video_brightness_flags flags;
> -};
> -
>  struct acpi_video_device {
>  	unsigned long device_id;
>  	struct acpi_video_device_flags flags;
> @@ -344,7 +331,7 @@ static const struct thermal_cooling_device_ops video_cooling_ops = {
>   */
>  
>  static int
> -acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
> +acpi_video_device_lcd_query_levels(acpi_handle handle,
>  				   union acpi_object **levels)
>  {
>  	int status;
> @@ -354,7 +341,7 @@ acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
>  
>  	*levels = NULL;
>  
> -	status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
> +	status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
>  	if (!ACPI_SUCCESS(status))
>  		return status;
>  	obj = (union acpi_object *)buffer.pointer;
> @@ -943,29 +930,18 @@ static int acpi_video_bqc_quirk(struct acpi_video_device *device,
>  	return 0;
>  }
>  
> -
> -/*
> - *  Arg:
> - *	device	: video output device (LCD, CRT, ..)
> - *
> - *  Return Value:
> - *	Maximum brightness level
> - *
> - *  Allocate and initialize device->brightness.
> - */
> -
> -static int
> -acpi_video_init_brightness(struct acpi_video_device *device)
> +int acpi_video_get_levels(struct acpi_device *device,
> +			  struct acpi_video_device_brightness **dev_br)
>  {
>  	union acpi_object *obj = NULL;
>  	int i, max_level = 0, count = 0, level_ac_battery = 0;
> -	unsigned long long level, level_old;
>  	union acpi_object *o;
>  	struct acpi_video_device_brightness *br = NULL;
> -	int result = -EINVAL;
> +	int result = 0;
>  	u32 value;
>  
> -	if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
> +	if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
> +								&obj))) {
>  		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
>  						"LCD brightness level\n"));
>  		goto out;
> @@ -1038,6 +1014,38 @@ acpi_video_init_brightness(struct acpi_video_device *device)
>  			    "Found unordered _BCL package"));
>  
>  	br->count = count;
> +	*dev_br = br;
> +
> +out:
> +	kfree(obj);
> +	return result;
> +out_free:
> +	kfree(br);
> +	goto out;
> +}
> +EXPORT_SYMBOL(acpi_video_get_levels);
> +
> +/*
> + *  Arg:
> + *	device	: video output device (LCD, CRT, ..)
> + *
> + *  Return Value:
> + *	Maximum brightness level
> + *
> + *  Allocate and initialize device->brightness.
> + */
> +
> +static int
> +acpi_video_init_brightness(struct acpi_video_device *device)
> +{
> +	int i, max_level = 0;
> +	unsigned long long level, level_old;
> +	struct acpi_video_device_brightness *br = NULL;
> +	int result = -EINVAL;
> +
> +	result = acpi_video_get_levels(device->dev, &br);
> +	if (result)
> +		return result;
>  	device->brightness = br;
>  
>  	/* _BQC uses INDEX while _BCL uses VALUE in some laptops */
> @@ -1080,17 +1088,13 @@ set_level:
>  		goto out_free_levels;
>  
>  	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
> -			  "found %d brightness levels\n", count - 2));
> -	kfree(obj);
> -	return result;
> +			  "found %d brightness levels\n", br->count - 2));
> +	return 0;
>  
>  out_free_levels:
>  	kfree(br->levels);
> -out_free:
>  	kfree(br);
> -out:
>  	device->brightness = NULL;
> -	kfree(obj);
>  	return result;
>  }
>  
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 9b012ff65220..4565e55dbef9 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -229,29 +229,9 @@ config INTEL_SOC_DTS_THERMAL
>  	  notification methods.The other trip is a critical trip point, which
>  	  was set by the driver based on the TJ MAX temperature.
>  
> -config INT340X_THERMAL
> -	tristate "ACPI INT340X thermal drivers"
> -	depends on X86 && ACPI
> -	select THERMAL_GOV_USER_SPACE
> -	select ACPI_THERMAL_REL
> -	select ACPI_FAN
> -	help
> -	  Newer laptops and tablets that use ACPI may have thermal sensors and
> -	  other devices with thermal control capabilities outside the core
> -	  CPU/SOC, for thermal safety reasons.
> -	  They are exposed for the OS to use via the INT3400 ACPI device object
> -	  as the master, and INT3401~INT340B ACPI device objects as the slaves.
> -	  Enable this to expose the temperature information and cooling ability
> -	  from these objects to userspace via the normal thermal framework.
> -	  This means that a wide range of applications and GUI widgets can show
> -	  the information to the user or use this information for making
> -	  decisions. For example, the Intel Thermal Daemon can use this
> -	  information to allow the user to select his laptop to run without
> -	  turning on the fans.
> -
> -config ACPI_THERMAL_REL
> -	tristate
> -	depends on ACPI
> +menu "ACPI INT340X thermal drivers"
> +source drivers/thermal/int340x_thermal/Kconfig
> +endmenu
>  
>  menu "Texas Instruments thermal drivers"
>  source "drivers/thermal/ti-soc-thermal/Kconfig"
> diff --git a/drivers/thermal/int340x_thermal/Makefile b/drivers/thermal/int340x_thermal/Makefile
> index ffe40bffaf1a..a9d0429be412 100644
> --- a/drivers/thermal/int340x_thermal/Makefile
> +++ b/drivers/thermal/int340x_thermal/Makefile
> @@ -1,4 +1,5 @@
>  obj-$(CONFIG_INT340X_THERMAL)	+= int3400_thermal.o
>  obj-$(CONFIG_INT340X_THERMAL)	+= int3402_thermal.o
>  obj-$(CONFIG_INT340X_THERMAL)	+= int3403_thermal.o
> +obj-$(CONFIG_INT3406_THERMAL)	+= int3406_thermal.o
>  obj-$(CONFIG_ACPI_THERMAL_REL)	+= acpi_thermal_rel.o
> diff --git a/drivers/thermal/int340x_thermal/int3406_thermal.c b/drivers/thermal/int340x_thermal/int3406_thermal.c
> new file mode 100644
> index 000000000000..162ddee4f937
> --- /dev/null
> +++ b/drivers/thermal/int340x_thermal/int3406_thermal.c
> @@ -0,0 +1,230 @@
> +/*
> + * INT3406 thermal driver for display participant device
> + *
> + * Copyright (C) 2014, Intel Corporation
> + * Authors: Aaron Lu <aaron.lu@...el.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/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/acpi.h>
> +#include <linux/backlight.h>
> +#include <linux/thermal.h>
> +#include <acpi/video.h>
> +
> +#define INT3406_BRIGHTNESS_LIMITS_CHANGED	0x80
> +
> +struct int3406_thermal_data {
> +	int upper_limit;
> +	int upper_limit_index;
> +	int lower_limit;
> +	int lower_limit_index;
> +	acpi_handle handle;
> +	struct acpi_video_device_brightness *br;
> +	struct backlight_device *raw_bd;
> +	struct thermal_cooling_device *cooling_dev;
> +};
> +
> +static int int3406_thermal_to_raw(int level, struct int3406_thermal_data *d)
> +{
> +	int max_level = d->br->levels[d->br->count - 1];
> +	int raw_max = d->raw_bd->props.max_brightness;
> +
> +	return level * raw_max / max_level;
> +}
> +
> +static int int3406_thermal_to_acpi(int level, struct int3406_thermal_data *d)
> +{
> +	int raw_max = d->raw_bd->props.max_brightness;
> +	int max_level = d->br->levels[d->br->count - 1];
> +
> +	return level * max_level / raw_max;
> +}
> +
> +static int
> +int3406_thermal_get_max_state(struct thermal_cooling_device *cooling_dev,
> +			      unsigned long *state)
> +{
> +	struct int3406_thermal_data *d = cooling_dev->devdata;
> +	int index = d->lower_limit_index ? d->lower_limit_index : 2;
> +
> +	*state = d->br->count - 1 - index;
> +	return 0;
> +}
> +
> +static int
> +int3406_thermal_set_cur_state(struct thermal_cooling_device *cooling_dev,
> +			      unsigned long state)
> +{
> +	struct int3406_thermal_data *d = cooling_dev->devdata;
> +	int level, raw_level;
> +
> +	if (state > d->br->count - 3)
> +		return -EINVAL;
> +
> +	state = d->br->count - 1 - state;
> +	level = d->br->levels[state];
> +
> +	if ((d->upper_limit && level > d->upper_limit) ||
> +	    (d->lower_limit && level < d->lower_limit))
> +		return -EINVAL;
> +
> +	raw_level = int3406_thermal_to_raw(level, d);
> +	return backlight_device_set_brightness(d->raw_bd, raw_level);
> +}
> +
> +static int
> +int3406_thermal_get_cur_state(struct thermal_cooling_device *cooling_dev,
> +			      unsigned long *state)
> +{
> +	struct int3406_thermal_data *d = cooling_dev->devdata;
> +	int raw_level, level, i;
> +
> +	raw_level = d->raw_bd->props.brightness;
> +	level = int3406_thermal_to_acpi(raw_level, d);
> +
> +	/*
> +	 * There is no 1:1 mapping between the firmware interface level with the
> +	 * raw interface level, we will have to find one that is close enough.
> +	 */
> +	for (i = 2; i < d->br->count - 1; i++) {
> +		if (level >= d->br->levels[i] && level <= d->br->levels[i + 1])
> +			break;
> +	}
> +
> +	*state = i;
> +	return 0;
> +}
> +
> +static const struct thermal_cooling_device_ops video_cooling_ops = {
> +	.get_max_state = int3406_thermal_get_max_state,
> +	.get_cur_state = int3406_thermal_get_cur_state,
> +	.set_cur_state = int3406_thermal_set_cur_state,
> +};
> +
> +static int int3406_thermal_get_index(int *array, int nr, int value)
> +{
> +	int i;
> +
> +	for (i = 0; i < nr; i++) {
> +		if (array[i] == value)
> +			break;
> +	}
> +	return i == nr ? -ENOENT : i;
> +}
> +
> +static void int3406_thermal_get_limit(struct int3406_thermal_data *d)
> +{
> +	acpi_status status;
> +	unsigned long long lower_limit, upper_limit;
> +	int index;
> +
> +	status = acpi_evaluate_integer(d->handle, "DDDL", NULL, &lower_limit);
> +	if (ACPI_SUCCESS(status)) {
> +		index = int3406_thermal_get_index(d->br->levels, d->br->count,
> +						  lower_limit);
> +		if (index > 0) {
> +			d->lower_limit = (int)lower_limit;
> +			d->lower_limit_index = index;
> +		}
> +	}
> +
> +	status = acpi_evaluate_integer(d->handle, "DDPC", NULL, &upper_limit);
> +	if (ACPI_SUCCESS(status)) {
> +		index = int3406_thermal_get_index(d->br->levels, d->br->count,
> +						  upper_limit);
> +		if (index > 0) {
> +			d->upper_limit = (int)upper_limit;
> +			d->upper_limit_index = index;
> +		}
> +	}
> +}
> +
> +static void int3406_notify(acpi_handle handle, u32 event, void *data)
> +{
> +	if (event == INT3406_BRIGHTNESS_LIMITS_CHANGED)
> +		int3406_thermal_get_limit(data);
> +}
> +
> +static int int3406_thermal_probe(struct platform_device *pdev)
> +{
> +	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
> +	struct int3406_thermal_data *d;
> +	struct backlight_device *bd;
> +	int ret;
> +
> +	if (!ACPI_HANDLE(&pdev->dev))
> +		return -ENODEV;
> +
> +	d = devm_kzalloc(&pdev->dev, sizeof(*d), GFP_KERNEL);
> +	if (!d)
> +		return -ENOMEM;
> +	d->handle = ACPI_HANDLE(&pdev->dev);
> +
> +	bd = backlight_device_get_by_type(BACKLIGHT_RAW);
> +	if (!bd)
> +		return -ENODEV;
> +	d->raw_bd = bd;
> +
> +	ret = acpi_video_get_levels(ACPI_COMPANION(&pdev->dev), &d->br);
> +	if (ret)
> +		return ret;
> +
> +	int3406_thermal_get_limit(d);
> +
> +	d->cooling_dev = thermal_cooling_device_register(acpi_device_bid(adev),
> +							 d, &video_cooling_ops);
> +	if (IS_ERR(d->cooling_dev))
> +		goto err;
> +
> +	ret = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
> +					  int3406_notify, d);
> +	if (ret)
> +		goto err_cdev;
> +
> +	platform_set_drvdata(pdev, d);
> +
> +	return 0;
> +
> +err_cdev:
> +	thermal_cooling_device_unregister(d->cooling_dev);
> +err:
> +	kfree(d->br);
> +	return -ENODEV;
> +}
> +
> +static int int3406_thermal_remove(struct platform_device *pdev)
> +{
> +	struct int3406_thermal_data *d = platform_get_drvdata(pdev);
> +
> +	thermal_cooling_device_unregister(platform_get_drvdata(pdev));
> +	kfree(d->br);
> +	return 0;
> +}
> +
> +static const struct acpi_device_id int3406_thermal_match[] = {
> +	{"INT3406", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(acpi, int3406_thermal_match);
> +
> +static struct platform_driver int3406_thermal_driver = {
> +	.probe = int3406_thermal_probe,
> +	.remove = int3406_thermal_remove,
> +	.driver = {
> +		   .name = "int3406 thermal",
> +		   .owner = THIS_MODULE,
> +		   .acpi_match_table = int3406_thermal_match,
> +		   },
> +};
> +
> +module_platform_driver(int3406_thermal_driver);
> +
> +MODULE_DESCRIPTION("INT3406 Thermal driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> index bddc8b17a4d8..bea749329236 100644
> --- a/drivers/video/backlight/backlight.c
> +++ b/drivers/video/backlight/backlight.c
> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
>  	return sprintf(buf, "%d\n", bd->props.brightness);
>  }
>  
> -static ssize_t brightness_store(struct device *dev,
> -		struct device_attribute *attr, const char *buf, size_t count)
> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
>  {
> -	int rc;
> -	struct backlight_device *bd = to_backlight_device(dev);
> -	unsigned long brightness;
> -
> -	rc = kstrtoul(buf, 0, &brightness);
> -	if (rc)
> -		return rc;
> -
> -	rc = -ENXIO;
> +	int rc = -ENXIO;
>  
>  	mutex_lock(&bd->ops_lock);
>  	if (bd->ops) {
>  		if (brightness > bd->props.max_brightness)
>  			rc = -EINVAL;
>  		else {
> -			pr_debug("set brightness to %lu\n", brightness);
> +			pr_debug("set brightness to %u\n", brightness);
>  			bd->props.brightness = brightness;
>  			backlight_update_status(bd);
> -			rc = count;
> +			rc = 0;
>  		}
>  	}
>  	mutex_unlock(&bd->ops_lock);
> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
>  
>  	return rc;
>  }
> +EXPORT_SYMBOL(backlight_device_set_brightness);
> +
> +static ssize_t brightness_store(struct device *dev,
> +		struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	int rc;
> +	struct backlight_device *bd = to_backlight_device(dev);
> +	unsigned long brightness;
> +
> +	rc = kstrtoul(buf, 0, &brightness);
> +	if (rc)
> +		return rc;
> +
> +	rc = backlight_device_set_brightness(bd, brightness);
> +
> +	return rc ? rc : count;
> +}
>  static DEVICE_ATTR_RW(brightness);
>  
>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
>  }
>  EXPORT_SYMBOL(backlight_device_register);
>  
> -bool backlight_device_registered(enum backlight_type type)
> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
>  {
>  	bool found = false;
>  	struct backlight_device *bd;
> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
>  	}
>  	mutex_unlock(&backlight_dev_list_mutex);
>  
> -	return found;
> +	return found ? bd : NULL;
> +}
> +EXPORT_SYMBOL(backlight_device_get_by_type);
> +
> +bool backlight_device_registered(enum backlight_type type)
> +{
> +	return backlight_device_get_by_type(type) ? true : false;
>  }
>  EXPORT_SYMBOL(backlight_device_registered);
>  
> diff --git a/include/acpi/video.h b/include/acpi/video.h
> index 843ef1adfbfa..956300d2f214 100644
> --- a/include/acpi/video.h
> +++ b/include/acpi/video.h
> @@ -3,6 +3,19 @@
>  
>  #include <linux/errno.h> /* for ENODEV */
>  
> +struct acpi_video_brightness_flags {
> +	u8 _BCL_no_ac_battery_levels:1;	/* no AC/Battery levels in _BCL */
> +	u8 _BCL_reversed:1;		/* _BCL package is in a reversed order */
> +	u8 _BQC_use_index:1;		/* _BQC returns an index value */
> +};
> +
> +struct acpi_video_device_brightness {
> +	int curr;
> +	int count;
> +	int *levels;
> +	struct acpi_video_brightness_flags flags;
> +};
> +
>  struct acpi_device;
>  
>  #define ACPI_VIDEO_CLASS	"video"
> @@ -22,6 +35,8 @@ extern void acpi_video_unregister(void);
>  extern void acpi_video_unregister_backlight(void);
>  extern int acpi_video_get_edid(struct acpi_device *device, int type,
>  			       int device_id, void **edid);
> +extern int acpi_video_get_levels(struct acpi_device *device,
> +				struct acpi_video_device_brightness **dev_br);
>  extern bool acpi_video_verify_backlight_support(void);
>  #else
>  static inline int acpi_video_register(void) { return 0; }
> @@ -32,6 +47,11 @@ static inline int acpi_video_get_edid(struct acpi_device *device, int type,
>  {
>  	return -ENODEV;
>  }
> +static int acpi_video_get_levels(struct acpi_device *device,
> +			struct acpi_video_device_brightness **dev_br)
> +{
> +	return -ENODEV;
> +}
>  static inline bool acpi_video_verify_backlight_support(void) { return false; }
>  #endif
>  
> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> index adb14a8616df..c59a020df3f8 100644
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
>  extern bool backlight_device_registered(enum backlight_type type);
>  extern int backlight_register_notifier(struct notifier_block *nb);
>  extern int backlight_unregister_notifier(struct notifier_block *nb);
> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
>  
>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
>  


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