[PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[gavinli]

From: Gavin Li <git@thegavinli.com>

This driver adds support for coarse (on or off) fan control and
the keyboard backlight on newer Samsung laptops.
---
 drivers/platform/x86/Kconfig       |  10 ++
 drivers/platform/x86/Makefile      |   1 +
 drivers/platform/x86/samsung-wmi.c | 221 +++++++++++++++++++++++++++++++++++++
 3 files changed, 232 insertions(+)
 create mode 100644 drivers/platform/x86/samsung-wmi.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 9752761..96f4620 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
 	  To compile this driver as a module, choose M here: the module
 	  will be called samsung-laptop.
 
+config SAMSUNG_WMI
+	tristate "Samsung WMI driver (for newer Samsung laptops)"
+	depends on ACPI
+	depends on ACPI_WMI
+	select LEDS_CLASS
+	select NEW_LEDS
+	  ---help---
+	  This driver adds support for coarse (on or off) fan control
+	  and the keyboard backlight for newer Samsung laptops.
+
 config MXM_WMI
        tristate "WMI support for MXM Laptop Graphics"
        depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index f82232b..4c65e51 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)	+= xo1-rfkill.o
 obj-$(CONFIG_XO15_EBOOK)	+= xo15-ebook.o
 obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
 obj-$(CONFIG_SAMSUNG_LAPTOP)	+= samsung-laptop.o
+obj-$(CONFIG_SAMSUNG_WMI)	+= samsung-wmi.o
 obj-$(CONFIG_MXM_WMI)		+= mxm-wmi.o
 obj-$(CONFIG_INTEL_MID_POWER_BUTTON)	+= intel_mid_powerbtn.o
 obj-$(CONFIG_INTEL_OAKTRAIL)	+= intel_oaktrail.o
diff --git a/drivers/platform/x86/samsung-wmi.c b/drivers/platform/x86/samsung-wmi.c
new file mode 100644
index 0000000..c93cfe4
--- /dev/null
+++ b/drivers/platform/x86/samsung-wmi.c
@@ -0,0 +1,221 @@
+/*
+ *  Samsung WMI driver
+ *
+ *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/leds.h>
+#include <linux/platform_device.h>
+
+#define DRIVER_NAME "samsung-wmi"
+#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
+
+struct samsung_wmi_packet {
+	uint16_t magic;
+	uint16_t opcode;
+	uint8_t reqres;
+	uint8_t data[16];
+} __packed;
+
+static struct platform_device *samsung_wmi_device;
+
+static inline bool string_matches(const char *str, const char *kwd) {
+	size_t len = strlen(kwd);
+	if (strncmp(str, kwd, len) != 0)
+		return false;
+	return str[len] == '\0' || str[len] == '\n';
+}
+
+static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t len) {
+	struct samsung_wmi_packet inpkt = {
+		.magic = 0x5843,
+		.opcode = opcode,
+	};
+	struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
+	struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *outobj;
+	struct samsung_wmi_packet *outpkt;
+	acpi_status st;
+	int ret = -EIO;
+	/********/
+	if (len > 16) {
+		ret = -EINVAL;
+		goto err0;
+	}
+	memcpy(inpkt.data, data, len);
+	st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
+	if (ACPI_FAILURE(st)) {
+		dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed: %s\n",
+				opcode, acpi_format_exception(st));
+		goto err0;
+	}
+	outobj = outbuf.pointer;
+	if (outobj->type != ACPI_TYPE_BUFFER) {
+		goto err1;
+	}
+	if (outobj->buffer.length < sizeof(outpkt)) {
+		goto err1;
+	}
+	outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
+	memcpy(data, outpkt->data, len);
+	ret = 0;
+err1:
+	kfree(outobj);
+err0:
+	return ret;
+}
+
+static int samsung_wmi_method_call_with_unlock(
+		uint16_t unlock_opcode,
+		uint16_t opcode, void *data, size_t len) {
+	unsigned int unlock_data = 0xAABB;
+	int ret;
+	/********/
+	ret = samsung_wmi_method_call(unlock_opcode, &unlock_data, sizeof(unlock_data));
+	if (ret)
+		goto err0;
+	if (unlock_data != 0xCCDD) {
+		dev_err(&samsung_wmi_device->dev, "incorrect unlock response!\n");
+		ret = -EIO;
+		goto err0;
+	}
+	ret = samsung_wmi_method_call(opcode, data, len);
+err0:
+	return ret;
+}
+
+static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct device_attribute *attr,
+		char *buf) {
+	uint32_t data = 0;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data, sizeof(data)))
+		return -EIO;
+	if (data)
+		strcpy(buf, "[auto off] on\n");
+	else
+		strcpy(buf, "auto off [on]\n");
+	return strlen(buf);
+}
+
+static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count) {
+	uint32_t data;
+	if (string_matches(buf, "auto"))
+		data = 0x810001;
+	else if (string_matches(buf, "on"))
+		data = 0;
+	else if (string_matches(buf, "off"))
+		data = 0x800001;
+	else
+		return -EINVAL;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data, sizeof(data)))
+		return -EIO;
+	else
+		return count;
+}
+
+static void samsung_wmi_kbd_backlight_led_brightness_set(
+		struct led_classdev *cdev, enum led_brightness brightness) {
+	unsigned int data = brightness;
+	if (data > 4)
+		data = 4;
+	data = (data << 8) | 0x82;
+	/********/
+	samsung_wmi_method_call_with_unlock(0x78, 0x78, &data, sizeof(data));
+}
+
+static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR, samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
+
+static struct platform_driver samsung_wmi_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	},
+};
+
+static struct led_classdev samsung_wmi_kbd_backlight_led = {
+	.name = DRIVER_NAME "::kbd_backlight",
+	.max_brightness = 4,
+	.brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
+};
+
+static int kb_default_brightness = -1;
+module_param(kb_default_brightness, int, S_IRUGO);
+MODULE_PARM_DESC(kb_default_brightness,
+		"Default keyboard backlight brightness right after initialization");
+
+static int samsung_wmi_init(void) {
+	int ret;
+	// check whether method is present
+	if (!wmi_has_guid(WMI_GUID))
+		return -ENODEV;
+	// we're good to go
+	ret = platform_driver_register(&samsung_wmi_driver);
+	if (ret) {
+		goto err0;
+	}
+	samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
+	if (!samsung_wmi_device) {
+		ret = -ENOMEM;
+		goto err1;
+	}
+	ret = platform_device_add(samsung_wmi_device);
+	if (ret) {
+		goto err2;
+	}
+	ret = device_create_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	if (ret) {
+		goto err3;
+	}
+	ret = led_classdev_register(&samsung_wmi_device->dev,
+			&samsung_wmi_kbd_backlight_led);
+	if (ret) {
+		goto err4;
+	}
+	if (kb_default_brightness >= 0) {
+		led_set_brightness(&samsung_wmi_kbd_backlight_led, kb_default_brightness);
+	}
+	return 0;
+//err5:
+	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
+err4:
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+err3:
+	platform_device_del(samsung_wmi_device);
+err2:
+	platform_device_put(samsung_wmi_device);
+err1:
+	platform_driver_unregister(&samsung_wmi_driver);
+err0:
+	return ret;
+}
+
+static void samsung_wmi_exit(void) {
+	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	platform_device_unregister(samsung_wmi_device);
+	platform_driver_unregister(&samsung_wmi_driver);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gavin Li");
+MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
+MODULE_ALIAS("wmi:" WMI_GUID);
+module_init(samsung_wmi_init);
+module_exit(samsung_wmi_exit);
-- 
2.3.5

Re: [PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[Giedrius Statkevičius]

Hi Gavin Li,

On Tue, 7 Apr 2015, gavinli@thegavinli.com wrote:

> From: Gavin Li <git@thegavinli.com>
> 
> This driver adds support for coarse (on or off) fan control and
> the keyboard backlight on newer Samsung laptops.
> ---
>  drivers/platform/x86/Kconfig       |  10 ++
>  drivers/platform/x86/Makefile      |   1 +
>  drivers/platform/x86/samsung-wmi.c | 221 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 232 insertions(+)
>  create mode 100644 drivers/platform/x86/samsung-wmi.c
> 
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 9752761..96f4620 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called samsung-laptop.
>  
> +config SAMSUNG_WMI
> +	tristate "Samsung WMI driver (for newer Samsung laptops)"
> +	depends on ACPI
> +	depends on ACPI_WMI
> +	select LEDS_CLASS
> +	select NEW_LEDS
> +	  ---help---
> +	  This driver adds support for coarse (on or off) fan control
> +	  and the keyboard backlight for newer Samsung laptops.
> +
>  config MXM_WMI
>         tristate "WMI support for MXM Laptop Graphics"
>         depends on ACPI_WMI
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index f82232b..4c65e51 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)	+= xo1-rfkill.o
>  obj-$(CONFIG_XO15_EBOOK)	+= xo15-ebook.o
>  obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
>  obj-$(CONFIG_SAMSUNG_LAPTOP)	+= samsung-laptop.o
> +obj-$(CONFIG_SAMSUNG_WMI)	+= samsung-wmi.o
>  obj-$(CONFIG_MXM_WMI)		+= mxm-wmi.o
>  obj-$(CONFIG_INTEL_MID_POWER_BUTTON)	+= intel_mid_powerbtn.o
>  obj-$(CONFIG_INTEL_OAKTRAIL)	+= intel_oaktrail.o
> diff --git a/drivers/platform/x86/samsung-wmi.c b/drivers/platform/x86/samsung-wmi.c
> new file mode 100644
> index 0000000..c93cfe4
> --- /dev/null
> +++ b/drivers/platform/x86/samsung-wmi.c
> @@ -0,0 +1,221 @@
> +/*
> + *  Samsung WMI driver
> + *
> + *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation; either version 2 of the License, or
> + *  (at your option) any later version.
> + *
> + *  This program is distributed in the hope that it will be useful,
> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *  GNU General Public License for more details.
> + *
> + *  You should have received a copy of the GNU General Public License along
> + *  with this program; if not, write to the Free Software Foundation, Inc.,
> + *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/acpi.h>
> +#include <linux/leds.h>
> +#include <linux/platform_device.h>
> +
> +#define DRIVER_NAME "samsung-wmi"
> +#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
> +
> +struct samsung_wmi_packet {
> +	uint16_t magic;
> +	uint16_t opcode;
> +	uint8_t reqres;
> +	uint8_t data[16];
> +} __packed;
> +
> +static struct platform_device *samsung_wmi_device;
> +
> +static inline bool string_matches(const char *str, const char *kwd) {
> +	size_t len = strlen(kwd);
> +	if (strncmp(str, kwd, len) != 0)
> +		return false;
> +	return str[len] == '\0' || str[len] == '\n';
> +}
> +
> +static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t len) {
> +	struct samsung_wmi_packet inpkt = {
> +		.magic = 0x5843,
> +		.opcode = opcode,
> +	};
> +	struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
> +	struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *outobj;
> +	struct samsung_wmi_packet *outpkt;
> +	acpi_status st;
> +	int ret = -EIO;
> +	/********/

Comment is not needed

> +	if (len > 16) {
> +		ret = -EINVAL;
> +		goto err0;
> +	}
> +	memcpy(inpkt.data, data, len);
> +	st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
> +	if (ACPI_FAILURE(st)) {
> +		dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed: %s\n",
> +				opcode, acpi_format_exception(st));
> +		goto err0;
> +	}
> +	outobj = outbuf.pointer;
> +	if (outobj->type != ACPI_TYPE_BUFFER) {
> +		goto err1;
> +	}
> +	if (outobj->buffer.length < sizeof(outpkt)) {
> +		goto err1;
> +	}

Don't need {} here.

> +	outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
> +	memcpy(data, outpkt->data, len);
> +	ret = 0;
> +err1:
> +	kfree(outobj);
> +err0:
> +	return ret;

Could really improve the labels

> +}
> +
> +static int samsung_wmi_method_call_with_unlock(
> +		uint16_t unlock_opcode,
> +		uint16_t opcode, void *data, size_t len) {
> +	unsigned int unlock_data = 0xAABB;
> +	int ret;
> +	/********/

Comment is not needed

> +	ret = samsung_wmi_method_call(unlock_opcode, &unlock_data, sizeof(unlock_data));
> +	if (ret)
> +		goto err0;
> +	if (unlock_data != 0xCCDD) {
> +		dev_err(&samsung_wmi_device->dev, "incorrect unlock response!\n");
> +		ret = -EIO;
> +		goto err0;
> +	}
> +	ret = samsung_wmi_method_call(opcode, data, len);
> +err0:
> +	return ret;

Could improve the label

> +}
> +
> +static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct device_attribute *attr,
> +		char *buf) {
> +	uint32_t data = 0;
> +	if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data, sizeof(data)))
> +		return -EIO;
> +	if (data)
> +		strcpy(buf, "[auto off] on\n");
> +	else
> +		strcpy(buf, "auto off [on]\n");
> +	return strlen(buf);
> +}
> +
> +static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct device_attribute *attr,
> +		const char *buf, size_t count) {
> +	uint32_t data;
> +	if (string_matches(buf, "auto"))
> +		data = 0x810001;
> +	else if (string_matches(buf, "on"))
> +		data = 0;
> +	else if (string_matches(buf, "off"))
> +		data = 0x800001;
> +	else
> +		return -EINVAL;
> +	if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data, sizeof(data)))
> +		return -EIO;
> +	else
> +		return count;
> +}
> +
> +static void samsung_wmi_kbd_backlight_led_brightness_set(
> +		struct led_classdev *cdev, enum led_brightness brightness) {
> +	unsigned int data = brightness;
> +	if (data > 4)
> +		data = 4;
> +	data = (data << 8) | 0x82;
> +	/********/

This comment is not needed

> +	samsung_wmi_method_call_with_unlock(0x78, 0x78, &data, sizeof(data));
> +}
> +
> +static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR, samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
> +
> +static struct platform_driver samsung_wmi_driver = {
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.owner = THIS_MODULE,
> +	},

If I remember correctly you don't need to set .owner to THIS_MODULE anymore

> +};
> +
> +static struct led_classdev samsung_wmi_kbd_backlight_led = {
> +	.name = DRIVER_NAME "::kbd_backlight",
> +	.max_brightness = 4,
> +	.brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
> +};
> +
> +static int kb_default_brightness = -1;
> +module_param(kb_default_brightness, int, S_IRUGO);
> +MODULE_PARM_DESC(kb_default_brightness,
> +		"Default keyboard backlight brightness right after initialization");
> +
> +static int samsung_wmi_init(void) {
> +	int ret;
> +	// check whether method is present
> +	if (!wmi_has_guid(WMI_GUID))
> +		return -ENODEV;
> +	// we're good to go
> +	ret = platform_driver_register(&samsung_wmi_driver);
> +	if (ret) {
> +		goto err0;
> +	}

{} are not needed if there is only one statement

> +	samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
> +	if (!samsung_wmi_device) {
> +		ret = -ENOMEM;
> +		goto err1;
> +	}
> +	ret = platform_device_add(samsung_wmi_device);
> +	if (ret) {
> +		goto err2;
> +	}

Same

> +	ret = device_create_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +	if (ret) {
> +		goto err3;
> +	}
Same

> +	ret = led_classdev_register(&samsung_wmi_device->dev,
> +			&samsung_wmi_kbd_backlight_led);
> +	if (ret) {
> +		goto err4;
> +	}

Same

> +	if (kb_default_brightness >= 0) {
> +		led_set_brightness(&samsung_wmi_kbd_backlight_led, kb_default_brightness);
> +	}

Same

> +	return 0;
> +//err5:
> +	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
> +err4:
> +	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +err3:
> +	platform_device_del(samsung_wmi_device);
> +err2:
> +	platform_device_put(samsung_wmi_device);
> +err1:
> +	platform_driver_unregister(&samsung_wmi_driver);
> +err0:
> +	return ret;

err5 is commented here so why not remove it? Also, you could think of better
label names. This is a good essay/rant on them:
https://plus.google.com/106378716002406849458/posts/dnanfhQ4mHQ

> +}
> +
> +static void samsung_wmi_exit(void) {
> +	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
> +	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +	platform_device_unregister(samsung_wmi_device);
> +	platform_driver_unregister(&samsung_wmi_driver);
> +}
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Gavin Li");
> +MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
> +MODULE_ALIAS("wmi:" WMI_GUID);
> +module_init(samsung_wmi_init);
> +module_exit(samsung_wmi_exit);
> -- 
> 2.3.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

Su pagarba / Regards,
Giedrius

[PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[gavinli]

From: Gavin Li <git@thegavinli.com>

This driver adds support for coarse (on or off) fan control and
the keyboard backlight on newer Samsung laptops.
---
 drivers/platform/x86/Kconfig       |  10 ++
 drivers/platform/x86/Makefile      |   1 +
 drivers/platform/x86/samsung-wmi.c | 217 +++++++++++++++++++++++++++++++++++++
 3 files changed, 228 insertions(+)
 create mode 100644 drivers/platform/x86/samsung-wmi.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 9752761..96f4620 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
 	  To compile this driver as a module, choose M here: the module
 	  will be called samsung-laptop.
 
+config SAMSUNG_WMI
+	tristate "Samsung WMI driver (for newer Samsung laptops)"
+	depends on ACPI
+	depends on ACPI_WMI
+	select LEDS_CLASS
+	select NEW_LEDS
+	  ---help---
+	  This driver adds support for coarse (on or off) fan control
+	  and the keyboard backlight for newer Samsung laptops.
+
 config MXM_WMI
        tristate "WMI support for MXM Laptop Graphics"
        depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index f82232b..4c65e51 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)	+= xo1-rfkill.o
 obj-$(CONFIG_XO15_EBOOK)	+= xo15-ebook.o
 obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
 obj-$(CONFIG_SAMSUNG_LAPTOP)	+= samsung-laptop.o
+obj-$(CONFIG_SAMSUNG_WMI)	+= samsung-wmi.o
 obj-$(CONFIG_MXM_WMI)		+= mxm-wmi.o
 obj-$(CONFIG_INTEL_MID_POWER_BUTTON)	+= intel_mid_powerbtn.o
 obj-$(CONFIG_INTEL_OAKTRAIL)	+= intel_oaktrail.o
diff --git a/drivers/platform/x86/samsung-wmi.c b/drivers/platform/x86/samsung-wmi.c
new file mode 100644
index 0000000..dfc4212
--- /dev/null
+++ b/drivers/platform/x86/samsung-wmi.c
@@ -0,0 +1,217 @@
+/*
+ *  Samsung WMI driver
+ *
+ *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/leds.h>
+#include <linux/platform_device.h>
+
+#define DRIVER_NAME "samsung-wmi"
+#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
+
+struct samsung_wmi_packet {
+	uint16_t magic;
+	uint16_t opcode;
+	uint8_t reqres;
+	uint8_t data[16];
+} __packed;
+
+static struct platform_device *samsung_wmi_device;
+
+static inline bool string_matches(const char *str, const char *kwd) {
+	size_t len = strlen(kwd);
+	if (strncmp(str, kwd, len) != 0)
+		return false;
+	return str[len] == '\0' || str[len] == '\n';
+}
+
+static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t len) {
+	struct samsung_wmi_packet inpkt = {
+		.magic = 0x5843,
+		.opcode = opcode,
+	};
+	struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
+	struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *outobj;
+	struct samsung_wmi_packet *outpkt;
+	acpi_status st;
+	int ret = -EIO;
+	if (len > 16) {
+		ret = -EINVAL;
+		goto err_no_free;
+	}
+	memcpy(inpkt.data, data, len);
+	st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
+	if (ACPI_FAILURE(st)) {
+		dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed: %s\n",
+				opcode, acpi_format_exception(st));
+		goto err_no_free;
+	}
+	outobj = outbuf.pointer;
+	if (outobj->type != ACPI_TYPE_BUFFER)
+		goto err_free_outobj;
+	if (outobj->buffer.length < sizeof(outpkt))
+		goto err_free_outobj;
+	outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
+	memcpy(data, outpkt->data, len);
+	ret = 0;
+err_free_outobj:
+	kfree(outobj);
+err_no_free:
+	return ret;
+}
+
+static int samsung_wmi_method_call_with_unlock(
+		uint16_t unlock_opcode,
+		uint16_t opcode, void *data, size_t len) {
+	unsigned int unlock_data = 0xAABB;
+	int ret;
+	ret = samsung_wmi_method_call(unlock_opcode, &unlock_data, sizeof(unlock_data));
+	if (ret)
+		goto err;
+	if (unlock_data != 0xCCDD) {
+		dev_err(&samsung_wmi_device->dev, "incorrect unlock response!\n");
+		ret = -EIO;
+		goto err;
+	}
+	ret = samsung_wmi_method_call(opcode, data, len);
+err:
+	return ret;
+}
+
+static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct device_attribute *attr,
+		char *buf) {
+	uint32_t data = 0;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data, sizeof(data)))
+		return -EIO;
+	if (data)
+		strcpy(buf, "[auto off] on\n");
+	else
+		strcpy(buf, "auto off [on]\n");
+	return strlen(buf);
+}
+
+static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count) {
+	uint32_t data;
+	if (string_matches(buf, "auto"))
+		data = 0x810001;
+	else if (string_matches(buf, "on"))
+		data = 0;
+	else if (string_matches(buf, "off"))
+		data = 0x800001;
+	else
+		return -EINVAL;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data, sizeof(data)))
+		return -EIO;
+	else
+		return count;
+}
+
+static void samsung_wmi_kbd_backlight_led_brightness_set(
+		struct led_classdev *cdev, enum led_brightness brightness) {
+	unsigned int data = brightness;
+	if (data > 4)
+		data = 4;
+	data = (data << 8) | 0x82;
+	samsung_wmi_method_call_with_unlock(0x78, 0x78, &data, sizeof(data));
+}
+
+static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR, samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
+
+static struct platform_driver samsung_wmi_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+	},
+};
+
+static struct led_classdev samsung_wmi_kbd_backlight_led = {
+	.name = DRIVER_NAME "::kbd_backlight",
+	.max_brightness = 4,
+	.brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
+};
+
+static int kb_default_brightness = -1;
+module_param(kb_default_brightness, int, S_IRUGO);
+MODULE_PARM_DESC(kb_default_brightness,
+		"Default keyboard backlight brightness right after initialization");
+
+static int samsung_wmi_init(void) {
+	int ret;
+
+	// check whether method is present
+	if (!wmi_has_guid(WMI_GUID))
+		return -ENODEV;
+
+	// we're good to go
+	ret = platform_driver_register(&samsung_wmi_driver);
+	if (ret)
+		goto err_no_free;
+
+	samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
+	if (!samsung_wmi_device) {
+		ret = -ENOMEM;
+		goto err_unregister_driver;
+	}
+
+	ret = platform_device_add(samsung_wmi_device);
+	if (ret)
+		goto err_put_device;
+
+	ret = device_create_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	if (ret)
+		goto err_del_device;
+
+	ret = led_classdev_register(&samsung_wmi_device->dev,
+			&samsung_wmi_kbd_backlight_led);
+	if (ret)
+		goto err_remove_file;
+
+	if (kb_default_brightness >= 0)
+		led_set_brightness(&samsung_wmi_kbd_backlight_led, kb_default_brightness);
+
+	return 0;
+
+err_remove_file:
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+err_del_device:
+	platform_device_del(samsung_wmi_device);
+err_put_device:
+	platform_device_put(samsung_wmi_device);
+err_unregister_driver:
+	platform_driver_unregister(&samsung_wmi_driver);
+err_no_free:
+	return ret;
+}
+
+static void samsung_wmi_exit(void) {
+	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	platform_device_unregister(samsung_wmi_device);
+	platform_driver_unregister(&samsung_wmi_driver);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gavin Li");
+MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
+MODULE_ALIAS("wmi:" WMI_GUID);
+module_init(samsung_wmi_init);
+module_exit(samsung_wmi_exit);
-- 
2.3.5

(unknown),

[gavinli]

Oops, forgot to CC the patch to you. Thanks for the advice.

[PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[gavinli]

From: Gavin Li <git@thegavinli.com>

This driver adds support for coarse (on or off) fan control and
the keyboard backlight on newer Samsung laptops.
---
 drivers/platform/x86/Kconfig       |  10 ++
 drivers/platform/x86/Makefile      |   1 +
 drivers/platform/x86/samsung-wmi.c | 217 +++++++++++++++++++++++++++++++++++++
 3 files changed, 228 insertions(+)
 create mode 100644 drivers/platform/x86/samsung-wmi.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 9752761..96f4620 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
 	  To compile this driver as a module, choose M here: the module
 	  will be called samsung-laptop.
 
+config SAMSUNG_WMI
+	tristate "Samsung WMI driver (for newer Samsung laptops)"
+	depends on ACPI
+	depends on ACPI_WMI
+	select LEDS_CLASS
+	select NEW_LEDS
+	  ---help---
+	  This driver adds support for coarse (on or off) fan control
+	  and the keyboard backlight for newer Samsung laptops.
+
 config MXM_WMI
        tristate "WMI support for MXM Laptop Graphics"
        depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index f82232b..4c65e51 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)	+= xo1-rfkill.o
 obj-$(CONFIG_XO15_EBOOK)	+= xo15-ebook.o
 obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
 obj-$(CONFIG_SAMSUNG_LAPTOP)	+= samsung-laptop.o
+obj-$(CONFIG_SAMSUNG_WMI)	+= samsung-wmi.o
 obj-$(CONFIG_MXM_WMI)		+= mxm-wmi.o
 obj-$(CONFIG_INTEL_MID_POWER_BUTTON)	+= intel_mid_powerbtn.o
 obj-$(CONFIG_INTEL_OAKTRAIL)	+= intel_oaktrail.o
diff --git a/drivers/platform/x86/samsung-wmi.c b/drivers/platform/x86/samsung-wmi.c
new file mode 100644
index 0000000..dfc4212
--- /dev/null
+++ b/drivers/platform/x86/samsung-wmi.c
@@ -0,0 +1,217 @@
+/*
+ *  Samsung WMI driver
+ *
+ *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/leds.h>
+#include <linux/platform_device.h>
+
+#define DRIVER_NAME "samsung-wmi"
+#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
+
+struct samsung_wmi_packet {
+	uint16_t magic;
+	uint16_t opcode;
+	uint8_t reqres;
+	uint8_t data[16];
+} __packed;
+
+static struct platform_device *samsung_wmi_device;
+
+static inline bool string_matches(const char *str, const char *kwd) {
+	size_t len = strlen(kwd);
+	if (strncmp(str, kwd, len) != 0)
+		return false;
+	return str[len] == '\0' || str[len] == '\n';
+}
+
+static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t len) {
+	struct samsung_wmi_packet inpkt = {
+		.magic = 0x5843,
+		.opcode = opcode,
+	};
+	struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
+	struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *outobj;
+	struct samsung_wmi_packet *outpkt;
+	acpi_status st;
+	int ret = -EIO;
+	if (len > 16) {
+		ret = -EINVAL;
+		goto err_no_free;
+	}
+	memcpy(inpkt.data, data, len);
+	st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
+	if (ACPI_FAILURE(st)) {
+		dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed: %s\n",
+				opcode, acpi_format_exception(st));
+		goto err_no_free;
+	}
+	outobj = outbuf.pointer;
+	if (outobj->type != ACPI_TYPE_BUFFER)
+		goto err_free_outobj;
+	if (outobj->buffer.length < sizeof(outpkt))
+		goto err_free_outobj;
+	outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
+	memcpy(data, outpkt->data, len);
+	ret = 0;
+err_free_outobj:
+	kfree(outobj);
+err_no_free:
+	return ret;
+}
+
+static int samsung_wmi_method_call_with_unlock(
+		uint16_t unlock_opcode,
+		uint16_t opcode, void *data, size_t len) {
+	unsigned int unlock_data = 0xAABB;
+	int ret;
+	ret = samsung_wmi_method_call(unlock_opcode, &unlock_data, sizeof(unlock_data));
+	if (ret)
+		goto err;
+	if (unlock_data != 0xCCDD) {
+		dev_err(&samsung_wmi_device->dev, "incorrect unlock response!\n");
+		ret = -EIO;
+		goto err;
+	}
+	ret = samsung_wmi_method_call(opcode, data, len);
+err:
+	return ret;
+}
+
+static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct device_attribute *attr,
+		char *buf) {
+	uint32_t data = 0;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data, sizeof(data)))
+		return -EIO;
+	if (data)
+		strcpy(buf, "[auto off] on\n");
+	else
+		strcpy(buf, "auto off [on]\n");
+	return strlen(buf);
+}
+
+static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count) {
+	uint32_t data;
+	if (string_matches(buf, "auto"))
+		data = 0x810001;
+	else if (string_matches(buf, "on"))
+		data = 0;
+	else if (string_matches(buf, "off"))
+		data = 0x800001;
+	else
+		return -EINVAL;
+	if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data, sizeof(data)))
+		return -EIO;
+	else
+		return count;
+}
+
+static void samsung_wmi_kbd_backlight_led_brightness_set(
+		struct led_classdev *cdev, enum led_brightness brightness) {
+	unsigned int data = brightness;
+	if (data > 4)
+		data = 4;
+	data = (data << 8) | 0x82;
+	samsung_wmi_method_call_with_unlock(0x78, 0x78, &data, sizeof(data));
+}
+
+static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR, samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
+
+static struct platform_driver samsung_wmi_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+	},
+};
+
+static struct led_classdev samsung_wmi_kbd_backlight_led = {
+	.name = DRIVER_NAME "::kbd_backlight",
+	.max_brightness = 4,
+	.brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
+};
+
+static int kb_default_brightness = -1;
+module_param(kb_default_brightness, int, S_IRUGO);
+MODULE_PARM_DESC(kb_default_brightness,
+		"Default keyboard backlight brightness right after initialization");
+
+static int samsung_wmi_init(void) {
+	int ret;
+
+	// check whether method is present
+	if (!wmi_has_guid(WMI_GUID))
+		return -ENODEV;
+
+	// we're good to go
+	ret = platform_driver_register(&samsung_wmi_driver);
+	if (ret)
+		goto err_no_free;
+
+	samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
+	if (!samsung_wmi_device) {
+		ret = -ENOMEM;
+		goto err_unregister_driver;
+	}
+
+	ret = platform_device_add(samsung_wmi_device);
+	if (ret)
+		goto err_put_device;
+
+	ret = device_create_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	if (ret)
+		goto err_del_device;
+
+	ret = led_classdev_register(&samsung_wmi_device->dev,
+			&samsung_wmi_kbd_backlight_led);
+	if (ret)
+		goto err_remove_file;
+
+	if (kb_default_brightness >= 0)
+		led_set_brightness(&samsung_wmi_kbd_backlight_led, kb_default_brightness);
+
+	return 0;
+
+err_remove_file:
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+err_del_device:
+	platform_device_del(samsung_wmi_device);
+err_put_device:
+	platform_device_put(samsung_wmi_device);
+err_unregister_driver:
+	platform_driver_unregister(&samsung_wmi_driver);
+err_no_free:
+	return ret;
+}
+
+static void samsung_wmi_exit(void) {
+	led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
+	device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
+	platform_device_unregister(samsung_wmi_device);
+	platform_driver_unregister(&samsung_wmi_driver);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gavin Li");
+MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
+MODULE_ALIAS("wmi:" WMI_GUID);
+module_init(samsung_wmi_init);
+module_exit(samsung_wmi_exit);
-- 
2.3.5

Re: [PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[Corentin Chary]

On Tue, Apr 7, 2015 at 6:53 PM,  <gavinli@thegavinli.com> wrote:
> From: Gavin Li <git@thegavinli.com>
>
> This driver adds support for coarse (on or off) fan control and
> the keyboard backlight on newer Samsung laptops.
> ---
>  drivers/platform/x86/Kconfig       |  10 ++
>  drivers/platform/x86/Makefile      |   1 +
>  drivers/platform/x86/samsung-wmi.c | 221 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 232 insertions(+)
>  create mode 100644 drivers/platform/x86/samsung-wmi.c
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 9752761..96f4620 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
>           To compile this driver as a module, choose M here: the module
>           will be called samsung-laptop.
>
> +config SAMSUNG_WMI
> +       tristate "Samsung WMI driver (for newer Samsung laptops)"
> +       depends on ACPI
> +       depends on ACPI_WMI
> +       select LEDS_CLASS
> +       select NEW_LEDS
> +         ---help---
> +         This driver adds support for coarse (on or off) fan control
> +         and the keyboard backlight for newer Samsung laptops.
> +
>  config MXM_WMI
>         tristate "WMI support for MXM Laptop Graphics"
>         depends on ACPI_WMI
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index f82232b..4c65e51 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)      += xo1-rfkill.o
>  obj-$(CONFIG_XO15_EBOOK)       += xo15-ebook.o
>  obj-$(CONFIG_IBM_RTL)          += ibm_rtl.o
>  obj-$(CONFIG_SAMSUNG_LAPTOP)   += samsung-laptop.o
> +obj-$(CONFIG_SAMSUNG_WMI)      += samsung-wmi.o
>  obj-$(CONFIG_MXM_WMI)          += mxm-wmi.o
>  obj-$(CONFIG_INTEL_MID_POWER_BUTTON)   += intel_mid_powerbtn.o
>  obj-$(CONFIG_INTEL_OAKTRAIL)   += intel_oaktrail.o
> diff --git a/drivers/platform/x86/samsung-wmi.c b/drivers/platform/x86/samsung-wmi.c
> new file mode 100644
> index 0000000..c93cfe4
> --- /dev/null
> +++ b/drivers/platform/x86/samsung-wmi.c
> @@ -0,0 +1,221 @@
> +/*
> + *  Samsung WMI driver
> + *
> + *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation; either version 2 of the License, or
> + *  (at your option) any later version.
> + *
> + *  This program is distributed in the hope that it will be useful,
> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *  GNU General Public License for more details.
> + *
> + *  You should have received a copy of the GNU General Public License along
> + *  with this program; if not, write to the Free Software Foundation, Inc.,
> + *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/acpi.h>
> +#include <linux/leds.h>
> +#include <linux/platform_device.h>
> +
> +#define DRIVER_NAME "samsung-wmi"
> +#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
> +
> +struct samsung_wmi_packet {
> +       uint16_t magic;
> +       uint16_t opcode;
> +       uint8_t reqres;
> +       uint8_t data[16];
> +} __packed;
> +
> +static struct platform_device *samsung_wmi_device;
> +
> +static inline bool string_matches(const char *str, const char *kwd) {
> +       size_t len = strlen(kwd);
> +       if (strncmp(str, kwd, len) != 0)
> +               return false;
> +       return str[len] == '\0' || str[len] == '\n';
> +}
> +
> +static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t len) {
> +       struct samsung_wmi_packet inpkt = {
> +               .magic = 0x5843,

Please use a constant instead of a magic number here.

> +               .opcode = opcode,
> +       };
> +       struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
> +       struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
> +       union acpi_object *outobj;
> +       struct samsung_wmi_packet *outpkt;
> +       acpi_status st;
> +       int ret = -EIO;
> +       /********/
> +       if (len > 16) {

Please use a constant instead of 16 here.

> +               ret = -EINVAL;
> +               goto err0;
> +       }
> +       memcpy(inpkt.data, data, len);
> +       st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
> +       if (ACPI_FAILURE(st)) {
> +               dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed: %s\n",
> +                               opcode, acpi_format_exception(st));
> +               goto err0;
> +       }
> +       outobj = outbuf.pointer;
> +       if (outobj->type != ACPI_TYPE_BUFFER) {
> +               goto err1;
> +       }
> +       if (outobj->buffer.length < sizeof(outpkt)) {
> +               goto err1;
> +       }
> +       outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
> +       memcpy(data, outpkt->data, len);
> +       ret = 0;
> +err1:
> +       kfree(outobj);
> +err0:
> +       return ret;
> +}
> +
> +static int samsung_wmi_method_call_with_unlock(
> +               uint16_t unlock_opcode,
> +               uint16_t opcode, void *data, size_t len) {
> +       unsigned int unlock_data = 0xAABB;

Same

> +       int ret;
> +       /********/
> +       ret = samsung_wmi_method_call(unlock_opcode, &unlock_data, sizeof(unlock_data));
> +       if (ret)
> +               goto err0;
> +       if (unlock_data != 0xCCDD) {
> +               dev_err(&samsung_wmi_device->dev, "incorrect unlock response!\n");
> +               ret = -EIO;
> +               goto err0;
> +       }
> +       ret = samsung_wmi_method_call(opcode, data, len);
> +err0:
> +       return ret;
> +}
> +
> +static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct device_attribute *attr,
> +               char *buf) {
> +       uint32_t data = 0;
> +       if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data, sizeof(data)))
> +               return -EIO;
> +       if (data)
> +               strcpy(buf, "[auto off] on\n");
> +       else
> +               strcpy(buf, "auto off [on]\n");
> +       return strlen(buf);
> +}
> +
> +static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct device_attribute *attr,
> +               const char *buf, size_t count) {
> +       uint32_t data;
> +       if (string_matches(buf, "auto"))
> +               data = 0x810001;

Same, and other places

> +       else if (string_matches(buf, "on"))
> +               data = 0;
> +       else if (string_matches(buf, "off"))
> +               data = 0x800001;
> +       else
> +               return -EINVAL;
> +       if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data, sizeof(data)))
> +               return -EIO;
> +       else
> +               return count;
> +}
> +
> +static void samsung_wmi_kbd_backlight_led_brightness_set(
> +               struct led_classdev *cdev, enum led_brightness brightness) {
> +       unsigned int data = brightness;

Why sometime uint32_t and sometime unsigned int ?

> +       if (data > 4)
> +               data = 4;
> +       data = (data << 8) | 0x82;
> +       /********/
> +       samsung_wmi_method_call_with_unlock(0x78, 0x78, &data, sizeof(data));
> +}
> +
> +static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR, samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
> +
> +static struct platform_driver samsung_wmi_driver = {
> +       .driver = {
> +               .name = DRIVER_NAME,
> +               .owner = THIS_MODULE,
> +       },
> +};
> +
> +static struct led_classdev samsung_wmi_kbd_backlight_led = {
> +       .name = DRIVER_NAME "::kbd_backlight",
> +       .max_brightness = 4,
> +       .brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
> +};
> +
> +static int kb_default_brightness = -1;
> +module_param(kb_default_brightness, int, S_IRUGO);
> +MODULE_PARM_DESC(kb_default_brightness,
> +               "Default keyboard backlight brightness right after initialization");
> +
> +static int samsung_wmi_init(void) {
> +       int ret;
> +       // check whether method is present
> +       if (!wmi_has_guid(WMI_GUID))
> +               return -ENODEV;
> +       // we're good to go
> +       ret = platform_driver_register(&samsung_wmi_driver);
> +       if (ret) {
> +               goto err0;
> +       }
> +       samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
> +       if (!samsung_wmi_device) {
> +               ret = -ENOMEM;
> +               goto err1;
> +       }
> +       ret = platform_device_add(samsung_wmi_device);
> +       if (ret) {
> +               goto err2;
> +       }
> +       ret = device_create_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +       if (ret) {
> +               goto err3;
> +       }
> +       ret = led_classdev_register(&samsung_wmi_device->dev,
> +                       &samsung_wmi_kbd_backlight_led);
> +       if (ret) {
> +               goto err4;
> +       }
> +       if (kb_default_brightness >= 0) {
> +               led_set_brightness(&samsung_wmi_kbd_backlight_led, kb_default_brightness);
> +       }
> +       return 0;
> +//err5:
> +       led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
> +err4:

Instead of 'errX' please give a name related to what happen after the
label (or what failed just before)

> +       device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +err3:
> +       platform_device_del(samsung_wmi_device);
> +err2:
> +       platform_device_put(samsung_wmi_device);
> +err1:
> +       platform_driver_unregister(&samsung_wmi_driver);
> +err0:
> +       return ret;
> +}
> +
> +static void samsung_wmi_exit(void) {
> +       led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
> +       device_remove_file(&samsung_wmi_device->dev, &dev_attr_fan_mode);
> +       platform_device_unregister(samsung_wmi_device);
> +       platform_driver_unregister(&samsung_wmi_driver);
> +}
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Gavin Li");
> +MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
> +MODULE_ALIAS("wmi:" WMI_GUID);
> +module_init(samsung_wmi_init);
> +module_exit(samsung_wmi_exit);
> --
> 2.3.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Corentin Chary
http://xf.iksaif.net

Re: [PATCH] platform: add samsung-wmi driver for newer Samsung laptops

[Gavin Li]

Actually there is an issue that affects the functionality of the
driver; I will have to work on this a bit more first. Thanks for the
feedback.

Gavin

On Thu, Apr 16, 2015 at 3:30 AM, Gavin Li <gavinli@thegavinli.com> wrote:
> Actually there is an issue that affects the functionality of the driver; I
> will have to work on this a bit more first. Thanks for the feedback.
>
> Gavin
>
> On Thu, Apr 16, 2015 at 12:04 AM, Corentin Chary <corentin.chary@gmail.com>
> wrote:
>>
>> On Tue, Apr 7, 2015 at 6:53 PM,  <gavinli@thegavinli.com> wrote:
>> > From: Gavin Li <git@thegavinli.com>
>> >
>> > This driver adds support for coarse (on or off) fan control and
>> > the keyboard backlight on newer Samsung laptops.
>> > ---
>> >  drivers/platform/x86/Kconfig       |  10 ++
>> >  drivers/platform/x86/Makefile      |   1 +
>> >  drivers/platform/x86/samsung-wmi.c | 221
>> > +++++++++++++++++++++++++++++++++++++
>> >  3 files changed, 232 insertions(+)
>> >  create mode 100644 drivers/platform/x86/samsung-wmi.c
>> >
>> > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
>> > index 9752761..96f4620 100644
>> > --- a/drivers/platform/x86/Kconfig
>> > +++ b/drivers/platform/x86/Kconfig
>> > @@ -813,6 +813,16 @@ config SAMSUNG_LAPTOP
>> >           To compile this driver as a module, choose M here: the module
>> >           will be called samsung-laptop.
>> >
>> > +config SAMSUNG_WMI
>> > +       tristate "Samsung WMI driver (for newer Samsung laptops)"
>> > +       depends on ACPI
>> > +       depends on ACPI_WMI
>> > +       select LEDS_CLASS
>> > +       select NEW_LEDS
>> > +         ---help---
>> > +         This driver adds support for coarse (on or off) fan control
>> > +         and the keyboard backlight for newer Samsung laptops.
>> > +
>> >  config MXM_WMI
>> >         tristate "WMI support for MXM Laptop Graphics"
>> >         depends on ACPI_WMI
>> > diff --git a/drivers/platform/x86/Makefile
>> > b/drivers/platform/x86/Makefile
>> > index f82232b..4c65e51 100644
>> > --- a/drivers/platform/x86/Makefile
>> > +++ b/drivers/platform/x86/Makefile
>> > @@ -48,6 +48,7 @@ obj-$(CONFIG_XO1_RFKILL)      += xo1-rfkill.o
>> >  obj-$(CONFIG_XO15_EBOOK)       += xo15-ebook.o
>> >  obj-$(CONFIG_IBM_RTL)          += ibm_rtl.o
>> >  obj-$(CONFIG_SAMSUNG_LAPTOP)   += samsung-laptop.o
>> > +obj-$(CONFIG_SAMSUNG_WMI)      += samsung-wmi.o
>> >  obj-$(CONFIG_MXM_WMI)          += mxm-wmi.o
>> >  obj-$(CONFIG_INTEL_MID_POWER_BUTTON)   += intel_mid_powerbtn.o
>> >  obj-$(CONFIG_INTEL_OAKTRAIL)   += intel_oaktrail.o
>> > diff --git a/drivers/platform/x86/samsung-wmi.c
>> > b/drivers/platform/x86/samsung-wmi.c
>> > new file mode 100644
>> > index 0000000..c93cfe4
>> > --- /dev/null
>> > +++ b/drivers/platform/x86/samsung-wmi.c
>> > @@ -0,0 +1,221 @@
>> > +/*
>> > + *  Samsung WMI driver
>> > + *
>> > + *  Copyright (C) 2015 Gavin Li <git@thegavinli.com>
>> > + *
>> > + *  This program is free software; you can redistribute it and/or
>> > modify
>> > + *  it under the terms of the GNU General Public License as published
>> > by
>> > + *  the Free Software Foundation; either version 2 of the License, or
>> > + *  (at your option) any later version.
>> > + *
>> > + *  This program is distributed in the hope that it will be useful,
>> > + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
>> > + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> > + *  GNU General Public License for more details.
>> > + *
>> > + *  You should have received a copy of the GNU General Public License
>> > along
>> > + *  with this program; if not, write to the Free Software Foundation,
>> > Inc.,
>> > + *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>> > + */
>> > +
>> > +#include <linux/init.h>
>> > +#include <linux/module.h>
>> > +#include <linux/acpi.h>
>> > +#include <linux/leds.h>
>> > +#include <linux/platform_device.h>
>> > +
>> > +#define DRIVER_NAME "samsung-wmi"
>> > +#define WMI_GUID "C16C47BA-50E3-444A-AF3A-B1C348380001"
>> > +
>> > +struct samsung_wmi_packet {
>> > +       uint16_t magic;
>> > +       uint16_t opcode;
>> > +       uint8_t reqres;
>> > +       uint8_t data[16];
>> > +} __packed;
>> > +
>> > +static struct platform_device *samsung_wmi_device;
>> > +
>> > +static inline bool string_matches(const char *str, const char *kwd) {
>> > +       size_t len = strlen(kwd);
>> > +       if (strncmp(str, kwd, len) != 0)
>> > +               return false;
>> > +       return str[len] == '\0' || str[len] == '\n';
>> > +}
>> > +
>> > +static int samsung_wmi_method_call(uint16_t opcode, void *data, size_t
>> > len) {
>> > +       struct samsung_wmi_packet inpkt = {
>> > +               .magic = 0x5843,
>>
>> Please use a constant instead of a magic number here.
>>
>> > +               .opcode = opcode,
>> > +       };
>> > +       struct acpi_buffer inbuf = { sizeof(inpkt), &inpkt };
>> > +       struct acpi_buffer outbuf = { ACPI_ALLOCATE_BUFFER, NULL };
>> > +       union acpi_object *outobj;
>> > +       struct samsung_wmi_packet *outpkt;
>> > +       acpi_status st;
>> > +       int ret = -EIO;
>> > +       /********/
>> > +       if (len > 16) {
>>
>> Please use a constant instead of 16 here.
>>
>> > +               ret = -EINVAL;
>> > +               goto err0;
>> > +       }
>> > +       memcpy(inpkt.data, data, len);
>> > +       st = wmi_evaluate_method(WMI_GUID, 1, 0, &inbuf, &outbuf);
>> > +       if (ACPI_FAILURE(st)) {
>> > +               dev_err(&samsung_wmi_device->dev, "opcode 0x%x failed:
>> > %s\n",
>> > +                               opcode, acpi_format_exception(st));
>> > +               goto err0;
>> > +       }
>> > +       outobj = outbuf.pointer;
>> > +       if (outobj->type != ACPI_TYPE_BUFFER) {
>> > +               goto err1;
>> > +       }
>> > +       if (outobj->buffer.length < sizeof(outpkt)) {
>> > +               goto err1;
>> > +       }
>> > +       outpkt = (struct samsung_wmi_packet *)outobj->buffer.pointer;
>> > +       memcpy(data, outpkt->data, len);
>> > +       ret = 0;
>> > +err1:
>> > +       kfree(outobj);
>> > +err0:
>> > +       return ret;
>> > +}
>> > +
>> > +static int samsung_wmi_method_call_with_unlock(
>> > +               uint16_t unlock_opcode,
>> > +               uint16_t opcode, void *data, size_t len) {
>> > +       unsigned int unlock_data = 0xAABB;
>>
>> Same
>>
>> > +       int ret;
>> > +       /********/
>> > +       ret = samsung_wmi_method_call(unlock_opcode, &unlock_data,
>> > sizeof(unlock_data));
>> > +       if (ret)
>> > +               goto err0;
>> > +       if (unlock_data != 0xCCDD) {
>> > +               dev_err(&samsung_wmi_device->dev, "incorrect unlock
>> > response!\n");
>> > +               ret = -EIO;
>> > +               goto err0;
>> > +       }
>> > +       ret = samsung_wmi_method_call(opcode, data, len);
>> > +err0:
>> > +       return ret;
>> > +}
>> > +
>> > +static ssize_t samsung_wmi_fan_mode_show(struct device *dev, struct
>> > device_attribute *attr,
>> > +               char *buf) {
>> > +       uint32_t data = 0;
>> > +       if (samsung_wmi_method_call_with_unlock(0x31, 0x31, &data,
>> > sizeof(data)))
>> > +               return -EIO;
>> > +       if (data)
>> > +               strcpy(buf, "[auto off] on\n");
>> > +       else
>> > +               strcpy(buf, "auto off [on]\n");
>> > +       return strlen(buf);
>> > +}
>> > +
>> > +static ssize_t samsung_wmi_fan_mode_store(struct device *dev, struct
>> > device_attribute *attr,
>> > +               const char *buf, size_t count) {
>> > +       uint32_t data;
>> > +       if (string_matches(buf, "auto"))
>> > +               data = 0x810001;
>>
>> Same, and other places
>>
>> > +       else if (string_matches(buf, "on"))
>> > +               data = 0;
>> > +       else if (string_matches(buf, "off"))
>> > +               data = 0x800001;
>> > +       else
>> > +               return -EINVAL;
>> > +       if (samsung_wmi_method_call_with_unlock(0x31, 0x32, &data,
>> > sizeof(data)))
>> > +               return -EIO;
>> > +       else
>> > +               return count;
>> > +}
>> > +
>> > +static void samsung_wmi_kbd_backlight_led_brightness_set(
>> > +               struct led_classdev *cdev, enum led_brightness
>> > brightness) {
>> > +       unsigned int data = brightness;
>>
>> Why sometime uint32_t and sometime unsigned int ?
>>
>> > +       if (data > 4)
>> > +               data = 4;
>> > +       data = (data << 8) | 0x82;
>> > +       /********/
>> > +       samsung_wmi_method_call_with_unlock(0x78, 0x78, &data,
>> > sizeof(data));
>> > +}
>> > +
>> > +static DEVICE_ATTR(fan_mode, S_IRUGO | S_IWUSR,
>> > samsung_wmi_fan_mode_show, samsung_wmi_fan_mode_store);
>> > +
>> > +static struct platform_driver samsung_wmi_driver = {
>> > +       .driver = {
>> > +               .name = DRIVER_NAME,
>> > +               .owner = THIS_MODULE,
>> > +       },
>> > +};
>> > +
>> > +static struct led_classdev samsung_wmi_kbd_backlight_led = {
>> > +       .name = DRIVER_NAME "::kbd_backlight",
>> > +       .max_brightness = 4,
>> > +       .brightness_set = samsung_wmi_kbd_backlight_led_brightness_set,
>> > +};
>> > +
>> > +static int kb_default_brightness = -1;
>> > +module_param(kb_default_brightness, int, S_IRUGO);
>> > +MODULE_PARM_DESC(kb_default_brightness,
>> > +               "Default keyboard backlight brightness right after
>> > initialization");
>> > +
>> > +static int samsung_wmi_init(void) {
>> > +       int ret;
>> > +       // check whether method is present
>> > +       if (!wmi_has_guid(WMI_GUID))
>> > +               return -ENODEV;
>> > +       // we're good to go
>> > +       ret = platform_driver_register(&samsung_wmi_driver);
>> > +       if (ret) {
>> > +               goto err0;
>> > +       }
>> > +       samsung_wmi_device = platform_device_alloc(DRIVER_NAME, -1);
>> > +       if (!samsung_wmi_device) {
>> > +               ret = -ENOMEM;
>> > +               goto err1;
>> > +       }
>> > +       ret = platform_device_add(samsung_wmi_device);
>> > +       if (ret) {
>> > +               goto err2;
>> > +       }
>> > +       ret = device_create_file(&samsung_wmi_device->dev,
>> > &dev_attr_fan_mode);
>> > +       if (ret) {
>> > +               goto err3;
>> > +       }
>> > +       ret = led_classdev_register(&samsung_wmi_device->dev,
>> > +                       &samsung_wmi_kbd_backlight_led);
>> > +       if (ret) {
>> > +               goto err4;
>> > +       }
>> > +       if (kb_default_brightness >= 0) {
>> > +               led_set_brightness(&samsung_wmi_kbd_backlight_led,
>> > kb_default_brightness);
>> > +       }
>> > +       return 0;
>> > +//err5:
>> > +       led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
>> > +err4:
>>
>> Instead of 'errX' please give a name related to what happen after the
>> label (or what failed just before)
>>
>> > +       device_remove_file(&samsung_wmi_device->dev,
>> > &dev_attr_fan_mode);
>> > +err3:
>> > +       platform_device_del(samsung_wmi_device);
>> > +err2:
>> > +       platform_device_put(samsung_wmi_device);
>> > +err1:
>> > +       platform_driver_unregister(&samsung_wmi_driver);
>> > +err0:
>> > +       return ret;
>> > +}
>> > +
>> > +static void samsung_wmi_exit(void) {
>> > +       led_classdev_unregister(&samsung_wmi_kbd_backlight_led);
>> > +       device_remove_file(&samsung_wmi_device->dev,
>> > &dev_attr_fan_mode);
>> > +       platform_device_unregister(samsung_wmi_device);
>> > +       platform_driver_unregister(&samsung_wmi_driver);
>> > +}
>> > +
>> > +MODULE_LICENSE("GPL");
>> > +MODULE_AUTHOR("Gavin Li");
>> > +MODULE_DESCRIPTION("WMI driver for some Samsung laptops.");
>> > +MODULE_ALIAS("wmi:" WMI_GUID);
>> > +module_init(samsung_wmi_init);
>> > +module_exit(samsung_wmi_exit);
>> > --
>> > 2.3.5
>> >
>> > --
>> > To unsubscribe from this list: send the line "unsubscribe
>> > platform-driver-x86" in
>> > the body of a message to majordomo@vger.kernel.org
>> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
>>
>>
>> --
>> Corentin Chary
>> http://xf.iksaif.net
>
>