[mirror_ubuntu-bionic-kernel.git] / drivers / platform / x86 / dell-wmi-led.c

/*
 * Copyright (C) 2010 Dell Inc.
 * Louis Davis <louis_davis@dell.com>
 * Jim Dailey <jim_dailey@dell.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.
 *
 */

#include <linux/acpi.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/module.h>

MODULE_AUTHOR("Louis Davis/Jim Dailey");
MODULE_DESCRIPTION("Dell LED Control Driver");
MODULE_LICENSE("GPL");

#define DELL_LED_BIOS_GUID "F6E4FE6E-909D-47cb-8BAB-C9F6F2F8D396"
MODULE_ALIAS("wmi:" DELL_LED_BIOS_GUID);

/* Error Result Codes: */
#define INVALID_DEVICE_ID	250
#define INVALID_PARAMETER	251
#define INVALID_BUFFER		252
#define INTERFACE_ERROR		253
#define UNSUPPORTED_COMMAND	254
#define UNSPECIFIED_ERROR	255

/* Device ID */
#define DEVICE_ID_PANEL_BACK	1

/* LED Commands */
#define CMD_LED_ON	16
#define CMD_LED_OFF	17
#define CMD_LED_BLINK	18

struct bios_args {
	unsigned char length;
	unsigned char result_code;
	unsigned char device_id;
	unsigned char command;
	unsigned char on_time;
	unsigned char off_time;
};

static int dell_led_perform_fn(u8 length, u8 result_code, u8 device_id,
			       u8 command, u8 on_time, u8 off_time)
{
	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
	struct bios_args *bios_return;
	struct acpi_buffer input;
	union acpi_object *obj;
	acpi_status status;
	u8 return_code;

	struct bios_args args = {
		.length = length,
		.result_code = result_code,
		.device_id = device_id,
		.command = command,
		.on_time = on_time,
		.off_time = off_time
	};

	input.length = sizeof(struct bios_args);
	input.pointer = &args;

	status = wmi_evaluate_method(DELL_LED_BIOS_GUID, 0, 1, &input, &output);
	if (ACPI_FAILURE(status))
		return status;

	obj = output.pointer;

	if (!obj)
		return -EINVAL;
	if (obj->type != ACPI_TYPE_BUFFER) {
		kfree(obj);
		return -EINVAL;
	}

	bios_return = ((struct bios_args *)obj->buffer.pointer);
	return_code = bios_return->result_code;

	kfree(obj);

	return return_code;
}

static int led_on(void)
{
	return dell_led_perform_fn(3,	/* Length of command */
		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
		DEVICE_ID_PANEL_BACK,	/* Device ID */
		CMD_LED_ON,		/* Command */
		0,			/* not used */
		0);			/* not used */
}

static int led_off(void)
{
	return dell_led_perform_fn(3,	/* Length of command */
		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
		DEVICE_ID_PANEL_BACK,	/* Device ID */
		CMD_LED_OFF,		/* Command */
		0,			/* not used */
		0);			/* not used */
}

static int led_blink(unsigned char on_eighths, unsigned char off_eighths)
{
	return dell_led_perform_fn(5,	/* Length of command */
		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
		DEVICE_ID_PANEL_BACK,	/* Device ID */
		CMD_LED_BLINK,		/* Command */
		on_eighths,		/* blink on in eigths of a second */
		off_eighths);		/* blink off in eights of a second */
}

static void dell_led_set(struct led_classdev *led_cdev,
			 enum led_brightness value)
{
	if (value == LED_OFF)
		led_off();
	else
		led_on();
}

static int dell_led_blink(struct led_classdev *led_cdev,
			  unsigned long *delay_on, unsigned long *delay_off)
{
	unsigned long on_eighths;
	unsigned long off_eighths;

	/*
	 * The Dell LED delay is based on 125ms intervals.
	 * Need to round up to next interval.
	 */

	on_eighths = DIV_ROUND_UP(*delay_on, 125);
	on_eighths = clamp_t(unsigned long, on_eighths, 1, 255);
	*delay_on = on_eighths * 125;

	off_eighths = DIV_ROUND_UP(*delay_off, 125);
	off_eighths = clamp_t(unsigned long, off_eighths, 1, 255);
	*delay_off = off_eighths * 125;

	led_blink(on_eighths, off_eighths);

	return 0;
}

static struct led_classdev dell_led = {
	.name		= "dell::lid",
	.brightness	= LED_OFF,
	.max_brightness = 1,
	.brightness_set = dell_led_set,
	.blink_set	= dell_led_blink,
	.flags		= LED_CORE_SUSPENDRESUME,
};

static int __init dell_led_init(void)
{
	int error = 0;

	if (!wmi_has_guid(DELL_LED_BIOS_GUID))
		return -ENODEV;

	error = led_off();
	if (error != 0)
		return -ENODEV;

	return led_classdev_register(NULL, &dell_led);
}

static void __exit dell_led_exit(void)
{
	led_classdev_unregister(&dell_led);

	led_off();
}

module_init(dell_led_init);
module_exit(dell_led_exit);
Commit	Line	Data
72dcd8d0	1	/*
72dcd8d0 BR	2	* Copyright (C) 2010 Dell Inc.
	3	* Louis Davis <louis_davis@dell.com>
	4	* Jim Dailey <jim_dailey@dell.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as
	8	* published by the Free Software Foundation.
	9	*
	10	*/
	11
	12	#include <linux/acpi.h>
	13	#include <linux/leds.h>
5a0e3ad6	14	#include <linux/slab.h>
54f4dedb	15	#include <linux/module.h>
72dcd8d0 BR	16
	17	MODULE_AUTHOR("Louis Davis/Jim Dailey");
	18	MODULE_DESCRIPTION("Dell LED Control Driver");
	19	MODULE_LICENSE("GPL");
	20
	21	#define DELL_LED_BIOS_GUID "F6E4FE6E-909D-47cb-8BAB-C9F6F2F8D396"
	22	MODULE_ALIAS("wmi:" DELL_LED_BIOS_GUID);
	23
	24	/* Error Result Codes: */
	25	#define INVALID_DEVICE_ID 250
	26	#define INVALID_PARAMETER 251
	27	#define INVALID_BUFFER 252
	28	#define INTERFACE_ERROR 253
	29	#define UNSUPPORTED_COMMAND 254
	30	#define UNSPECIFIED_ERROR 255
	31
	32	/* Device ID */
	33	#define DEVICE_ID_PANEL_BACK 1
	34
	35	/* LED Commands */
	36	#define CMD_LED_ON 16
	37	#define CMD_LED_OFF 17
	38	#define CMD_LED_BLINK 18
	39
	40	struct bios_args {
	41	unsigned char length;
	42	unsigned char result_code;
	43	unsigned char device_id;
	44	unsigned char command;
	45	unsigned char on_time;
	46	unsigned char off_time;
	47	};
	48
ab768386 MK	49	static int dell_led_perform_fn(u8 length, u8 result_code, u8 device_id,
ab768386 MK	50	u8 command, u8 on_time, u8 off_time)
72dcd8d0	51	{
72dcd8d0	52	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
ab768386	53	struct bios_args *bios_return;
72dcd8d0	54	struct acpi_buffer input;
ab768386	55	union acpi_object *obj;
72dcd8d0	56	acpi_status status;
ab768386	57	u8 return_code;
72dcd8d0	58
ab768386 MK	59	struct bios_args args = {
	60	.length = length,
	61	.result_code = result_code,
	62	.device_id = device_id,
	63	.command = command,
	64	.on_time = on_time,
	65	.off_time = off_time
	66	};
72dcd8d0 BR	67
	68	input.length = sizeof(struct bios_args);
	69	input.pointer = &args;
	70
71596f5b	71	status = wmi_evaluate_method(DELL_LED_BIOS_GUID, 0, 1, &input, &output);
72dcd8d0 BR	72	if (ACPI_FAILURE(status))
	73	return status;
	74
	75	obj = output.pointer;
	76
	77	if (!obj)
	78	return -EINVAL;
ab768386	79	if (obj->type != ACPI_TYPE_BUFFER) {
72dcd8d0 BR	80	kfree(obj);
	81	return -EINVAL;
	82	}
	83
	84	bios_return = ((struct bios_args *)obj->buffer.pointer);
	85	return_code = bios_return->result_code;
	86
	87	kfree(obj);
	88
	89	return return_code;
	90	}
	91
	92	static int led_on(void)
	93	{
	94	return dell_led_perform_fn(3, /* Length of command */
	95	INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
	96	DEVICE_ID_PANEL_BACK, /* Device ID */
	97	CMD_LED_ON, /* Command */
	98	0, /* not used */
	99	0); /* not used */
	100	}
	101
	102	static int led_off(void)
	103	{
	104	return dell_led_perform_fn(3, /* Length of command */
	105	INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
	106	DEVICE_ID_PANEL_BACK, /* Device ID */
	107	CMD_LED_OFF, /* Command */
	108	0, /* not used */
	109	0); /* not used */
	110	}
	111
ab768386	112	static int led_blink(unsigned char on_eighths, unsigned char off_eighths)
72dcd8d0 BR	113	{
	114	return dell_led_perform_fn(5, /* Length of command */
	115	INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
	116	DEVICE_ID_PANEL_BACK, /* Device ID */
	117	CMD_LED_BLINK, /* Command */
	118	on_eighths, /* blink on in eigths of a second */
	119	off_eighths); /* blink off in eights of a second */
	120	}
	121
	122	static void dell_led_set(struct led_classdev *led_cdev,
ab768386	123	enum led_brightness value)
72dcd8d0 BR	124	{
	125	if (value == LED_OFF)
	126	led_off();
	127	else
	128	led_on();
	129	}
	130
	131	static int dell_led_blink(struct led_classdev *led_cdev,
ab768386	132	unsigned long delay_on, unsigned long delay_off)
72dcd8d0 BR	133	{
	134	unsigned long on_eighths;
	135	unsigned long off_eighths;
	136
ab768386 MK	137	/*
	138	* The Dell LED delay is based on 125ms intervals.
	139	* Need to round up to next interval.
	140	*/
72dcd8d0	141
ab768386 MK	142	on_eighths = DIV_ROUND_UP(*delay_on, 125);
ab768386 MK	143	on_eighths = clamp_t(unsigned long, on_eighths, 1, 255);
72dcd8d0 BR	144	delay_on = on_eighths 125;
72dcd8d0 BR	145
ab768386 MK	146	off_eighths = DIV_ROUND_UP(*delay_off, 125);
ab768386 MK	147	off_eighths = clamp_t(unsigned long, off_eighths, 1, 255);
72dcd8d0 BR	148	delay_off = off_eighths 125;
	149
	150	led_blink(on_eighths, off_eighths);
	151
	152	return 0;
	153	}
	154
	155	static struct led_classdev dell_led = {
	156	.name = "dell::lid",
	157	.brightness = LED_OFF,
	158	.max_brightness = 1,
	159	.brightness_set = dell_led_set,
	160	.blink_set = dell_led_blink,
	161	.flags = LED_CORE_SUSPENDRESUME,
	162	};
	163
	164	static int __init dell_led_init(void)
	165	{
	166	int error = 0;
	167
e5aa482a	168	if (!wmi_has_guid(DELL_LED_BIOS_GUID))
72dcd8d0 BR	169	return -ENODEV;
72dcd8d0 BR	170
e5aa482a MK	171	error = led_off();
	172	if (error != 0)
	173	return -ENODEV;
db6d8cc0	174
e5aa482a	175	return led_classdev_register(NULL, &dell_led);
72dcd8d0 BR	176	}
	177
	178	static void __exit dell_led_exit(void)
	179	{
e5aa482a	180	led_classdev_unregister(&dell_led);
72dcd8d0	181
e5aa482a	182	led_off();
72dcd8d0 BR	183	}
	184
	185	module_init(dell_led_init);
	186	module_exit(dell_led_exit);