[deliverable/linux.git] / drivers / gpu / drm / radeon / radeon_atpx_handler.c

/*
 * Copyright (c) 2010 Red Hat Inc.
 * Author : Dave Airlie <airlied@redhat.com>
 *
 * Licensed under GPLv2
 *
 * ATPX support for both Intel/ATI
 */
#include <linux/vga_switcheroo.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/pci.h>

#include "radeon_acpi.h"

struct radeon_atpx_functions {
	bool px_params;
	bool power_cntl;
	bool disp_mux_cntl;
	bool i2c_mux_cntl;
	bool switch_start;
	bool switch_end;
	bool disp_connectors_mapping;
	bool disp_detetion_ports;
};

struct radeon_atpx {
	acpi_handle handle;
	struct radeon_atpx_functions functions;
};

static struct radeon_atpx_priv {
	bool atpx_detected;
	/* handle for device - and atpx */
	acpi_handle dhandle;
	struct radeon_atpx atpx;
} radeon_atpx_priv;

struct atpx_verify_interface {
	u16 size;		/* structure size in bytes (includes size field) */
	u16 version;		/* version */
	u32 function_bits;	/* supported functions bit vector */
} __packed;

struct atpx_px_params {
	u16 size;		/* structure size in bytes (includes size field) */
	u32 valid_flags;	/* which flags are valid */
	u32 flags;		/* flags */
} __packed;

struct atpx_power_control {
	u16 size;
	u8 dgpu_state;
} __packed;

struct atpx_mux {
	u16 size;
	u16 mux;
} __packed;

bool radeon_has_atpx(void) {
	return radeon_atpx_priv.atpx_detected;
}

/**
 * radeon_atpx_call - call an ATPX method
 *
 * @handle: acpi handle
 * @function: the ATPX function to execute
 * @params: ATPX function params
 *
 * Executes the requested ATPX function (all asics).
 * Returns a pointer to the acpi output buffer.
 */
static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
					   struct acpi_buffer *params)
{
	acpi_status status;
	union acpi_object atpx_arg_elements[2];
	struct acpi_object_list atpx_arg;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };

	atpx_arg.count = 2;
	atpx_arg.pointer = &atpx_arg_elements[0];

	atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
	atpx_arg_elements[0].integer.value = function;

	if (params) {
		atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
		atpx_arg_elements[1].buffer.length = params->length;
		atpx_arg_elements[1].buffer.pointer = params->pointer;
	} else {
		/* We need a second fake parameter */
		atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
		atpx_arg_elements[1].integer.value = 0;
	}

	status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);

	/* Fail only if calling the method fails and ATPX is supported */
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		printk("failed to evaluate ATPX got %s\n",
		       acpi_format_exception(status));
		kfree(buffer.pointer);
		return NULL;
	}

	return buffer.pointer;
}

/**
 * radeon_atpx_parse_functions - parse supported functions
 *
 * @f: supported functions struct
 * @mask: supported functions mask from ATPX
 *
 * Use the supported functions mask from ATPX function
 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
 * are supported (all asics).
 */
static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
{
	f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
	f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
	f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
	f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
	f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
	f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
	f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
	f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
}

/**
 * radeon_atpx_validate_functions - validate ATPX functions
 *
 * @atpx: radeon atpx struct
 *
 * Validate that required functions are enabled (all asics).
 * returns 0 on success, error on failure.
 */
static int radeon_atpx_validate(struct radeon_atpx *atpx)
{
	/* make sure required functions are enabled */
	/* dGPU power control is required */
	atpx->functions.power_cntl = true;

	if (atpx->functions.px_params) {
		union acpi_object *info;
		struct atpx_px_params output;
		size_t size;
		u32 valid_bits;

		info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
		if (!info)
			return -EIO;

		memset(&output, 0, sizeof(output));

		size = *(u16 *) info->buffer.pointer;
		if (size < 10) {
			printk("ATPX buffer is too small: %zu\n", size);
			kfree(info);
			return -EINVAL;
		}
		size = min(sizeof(output), size);

		memcpy(&output, info->buffer.pointer, size);

		valid_bits = output.flags & output.valid_flags;
		/* if separate mux flag is set, mux controls are required */
		if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
			atpx->functions.i2c_mux_cntl = true;
			atpx->functions.disp_mux_cntl = true;
		}
		/* if any outputs are muxed, mux controls are required */
		if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
				  ATPX_TV_SIGNAL_MUXED |
				  ATPX_DFP_SIGNAL_MUXED))
			atpx->functions.disp_mux_cntl = true;

		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_verify_interface - verify ATPX
 *
 * @atpx: radeon atpx struct
 *
 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
 * to initialize ATPX and determine what features are supported
 * (all asics).
 * returns 0 on success, error on failure.
 */
static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
{
	union acpi_object *info;
	struct atpx_verify_interface output;
	size_t size;
	int err = 0;

	info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
	if (!info)
		return -EIO;

	memset(&output, 0, sizeof(output));

	size = *(u16 *) info->buffer.pointer;
	if (size < 8) {
		printk("ATPX buffer is too small: %zu\n", size);
		err = -EINVAL;
		goto out;
	}
	size = min(sizeof(output), size);

	memcpy(&output, info->buffer.pointer, size);

	/* TODO: check version? */
	printk("ATPX version %u, functions 0x%08x\n",
	       output.version, output.function_bits);

	radeon_atpx_parse_functions(&atpx->functions, output.function_bits);

out:
	kfree(info);
	return err;
}

/**
 * radeon_atpx_set_discrete_state - power up/down discrete GPU
 *
 * @atpx: atpx info struct
 * @state: discrete GPU state (0 = power down, 1 = power up)
 *
 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
 * power down/up the discrete GPU (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
{
	struct acpi_buffer params;
	union acpi_object *info;
	struct atpx_power_control input;

	if (atpx->functions.power_cntl) {
		input.size = 3;
		input.dgpu_state = state;
		params.length = input.size;
		params.pointer = &input;
		info = radeon_atpx_call(atpx->handle,
					ATPX_FUNCTION_POWER_CONTROL,
					&params);
		if (!info)
			return -EIO;
		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_switch_disp_mux - switch display mux
 *
 * @atpx: atpx info struct
 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 *
 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
 * switch the display mux between the discrete GPU and integrated GPU
 * (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
{
	struct acpi_buffer params;
	union acpi_object *info;
	struct atpx_mux input;

	if (atpx->functions.disp_mux_cntl) {
		input.size = 4;
		input.mux = mux_id;
		params.length = input.size;
		params.pointer = &input;
		info = radeon_atpx_call(atpx->handle,
					ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
					&params);
		if (!info)
			return -EIO;
		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
 *
 * @atpx: atpx info struct
 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 *
 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
 * (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
{
	struct acpi_buffer params;
	union acpi_object *info;
	struct atpx_mux input;

	if (atpx->functions.i2c_mux_cntl) {
		input.size = 4;
		input.mux = mux_id;
		params.length = input.size;
		params.pointer = &input;
		info = radeon_atpx_call(atpx->handle,
					ATPX_FUNCTION_I2C_MUX_CONTROL,
					&params);
		if (!info)
			return -EIO;
		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_switch_start - notify the sbios of a GPU switch
 *
 * @atpx: atpx info struct
 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 *
 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
 * function to notify the sbios that a switch between the discrete GPU and
 * integrated GPU has begun (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
{
	struct acpi_buffer params;
	union acpi_object *info;
	struct atpx_mux input;

	if (atpx->functions.switch_start) {
		input.size = 4;
		input.mux = mux_id;
		params.length = input.size;
		params.pointer = &input;
		info = radeon_atpx_call(atpx->handle,
					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
					&params);
		if (!info)
			return -EIO;
		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_switch_end - notify the sbios of a GPU switch
 *
 * @atpx: atpx info struct
 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 *
 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
 * function to notify the sbios that a switch between the discrete GPU and
 * integrated GPU has ended (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
{
	struct acpi_buffer params;
	union acpi_object *info;
	struct atpx_mux input;

	if (atpx->functions.switch_end) {
		input.size = 4;
		input.mux = mux_id;
		params.length = input.size;
		params.pointer = &input;
		info = radeon_atpx_call(atpx->handle,
					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
					&params);
		if (!info)
			return -EIO;
		kfree(info);
	}
	return 0;
}

/**
 * radeon_atpx_switchto - switch to the requested GPU
 *
 * @id: GPU to switch to
 *
 * Execute the necessary ATPX functions to switch between the discrete GPU and
 * integrated GPU (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
{
	u16 gpu_id;

	if (id == VGA_SWITCHEROO_IGD)
		gpu_id = ATPX_INTEGRATED_GPU;
	else
		gpu_id = ATPX_DISCRETE_GPU;

	radeon_atpx_switch_start(&radeon_atpx_priv.atpx, gpu_id);
	radeon_atpx_switch_disp_mux(&radeon_atpx_priv.atpx, gpu_id);
	radeon_atpx_switch_i2c_mux(&radeon_atpx_priv.atpx, gpu_id);
	radeon_atpx_switch_end(&radeon_atpx_priv.atpx, gpu_id);

	return 0;
}

/**
 * radeon_atpx_power_state - power down/up the requested GPU
 *
 * @id: GPU to power down/up
 * @state: requested power state (0 = off, 1 = on)
 *
 * Execute the necessary ATPX function to power down/up the discrete GPU
 * (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
				   enum vga_switcheroo_state state)
{
	/* on w500 ACPI can't change intel gpu state */
	if (id == VGA_SWITCHEROO_IGD)
		return 0;

	radeon_atpx_set_discrete_state(&radeon_atpx_priv.atpx, state);
	return 0;
}

/**
 * radeon_atpx_pci_probe_handle - look up the ATPX handle
 *
 * @pdev: pci device
 *
 * Look up the ATPX handles (all asics).
 * Returns true if the handles are found, false if not.
 */
static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
{
	acpi_handle dhandle, atpx_handle;
	acpi_status status;

	dhandle = ACPI_HANDLE(&pdev->dev);
	if (!dhandle)
		return false;

	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
	if (ACPI_FAILURE(status))
		return false;

	radeon_atpx_priv.dhandle = dhandle;
	radeon_atpx_priv.atpx.handle = atpx_handle;
	return true;
}

/**
 * radeon_atpx_init - verify the ATPX interface
 *
 * Verify the ATPX interface (all asics).
 * Returns 0 on success, error on failure.
 */
static int radeon_atpx_init(void)
{
	int r;

	/* set up the ATPX handle */
	r = radeon_atpx_verify_interface(&radeon_atpx_priv.atpx);
	if (r)
		return r;

	/* validate the atpx setup */
	r = radeon_atpx_validate(&radeon_atpx_priv.atpx);
	if (r)
		return r;

	return 0;
}

/**
 * radeon_atpx_get_client_id - get the client id
 *
 * @pdev: pci device
 *
 * look up whether we are the integrated or discrete GPU (all asics).
 * Returns the client id.
 */
static int radeon_atpx_get_client_id(struct pci_dev *pdev)
{
	if (radeon_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
		return VGA_SWITCHEROO_IGD;
	else
		return VGA_SWITCHEROO_DIS;
}

static const struct vga_switcheroo_handler radeon_atpx_handler = {
	.switchto = radeon_atpx_switchto,
	.power_state = radeon_atpx_power_state,
	.init = radeon_atpx_init,
	.get_client_id = radeon_atpx_get_client_id,
};

/**
 * radeon_atpx_detect - detect whether we have PX
 *
 * Check if we have a PX system (all asics).
 * Returns true if we have a PX system, false if not.
 */
static bool radeon_atpx_detect(void)
{
	char acpi_method_name[255] = { 0 };
	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
	struct pci_dev *pdev = NULL;
	bool has_atpx = false;
	int vga_count = 0;

	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
		vga_count++;

		has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
	}

	/* some newer PX laptops mark the dGPU as a non-VGA display device */
	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
		vga_count++;

		has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
	}

	if (has_atpx && vga_count == 2) {
		acpi_get_name(radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
		printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
		       acpi_method_name);
		radeon_atpx_priv.atpx_detected = true;
		return true;
	}
	return false;
}

/**
 * radeon_register_atpx_handler - register with vga_switcheroo
 *
 * Register the PX callbacks with vga_switcheroo (all asics).
 */
void radeon_register_atpx_handler(void)
{
	bool r;
	enum vga_switcheroo_handler_flags_t handler_flags = 0;

	/* detect if we have any ATPX + 2 VGA in the system */
	r = radeon_atpx_detect();
	if (!r)
		return;

	vga_switcheroo_register_handler(&radeon_atpx_handler, handler_flags);
}

/**
 * radeon_unregister_atpx_handler - unregister with vga_switcheroo
 *
 * Unregister the PX callbacks with vga_switcheroo (all asics).
 */
void radeon_unregister_atpx_handler(void)
{
	vga_switcheroo_unregister_handler();
}
Commit	Line	Data
6a9ee8af DA	1	/*
	2	* Copyright (c) 2010 Red Hat Inc.
	3	* Author : Dave Airlie <airlied@redhat.com>
	4	*
	5	* Licensed under GPLv2
	6	*
	7	* ATPX support for both Intel/ATI
	8	*/
6a9ee8af	9	#include <linux/vga_switcheroo.h>
5a0e3ad6	10	#include <linux/slab.h>
7b199811	11	#include <linux/acpi.h>
6a9ee8af DA	12	#include <linux/pci.h>
6a9ee8af DA	13
9e05b2f4	14	#include "radeon_acpi.h"
6a9ee8af	15
48fa412b AD	16	struct radeon_atpx_functions {
	17	bool px_params;
	18	bool power_cntl;
	19	bool disp_mux_cntl;
	20	bool i2c_mux_cntl;
	21	bool switch_start;
	22	bool switch_end;
	23	bool disp_connectors_mapping;
	24	bool disp_detetion_ports;
	25	};
	26
	27	struct radeon_atpx {
492b49a2	28	acpi_handle handle;
48fa412b AD	29	struct radeon_atpx_functions functions;
	30	};
	31
6a9ee8af DA	32	static struct radeon_atpx_priv {
	33	bool atpx_detected;
	34	/* handle for device - and atpx */
	35	acpi_handle dhandle;
48fa412b	36	struct radeon_atpx atpx;
6a9ee8af DA	37	} radeon_atpx_priv;
6a9ee8af DA	38
48fa412b AD	39	struct atpx_verify_interface {
	40	u16 size; /* structure size in bytes (includes size field) */
	41	u16 version; /* version */
	42	u32 function_bits; /* supported functions bit vector */
	43	} __packed;
	44
43a23aa4 AD	45	struct atpx_px_params {
	46	u16 size; /* structure size in bytes (includes size field) */
	47	u32 valid_flags; /* which flags are valid */
	48	u32 flags; /* flags */
	49	} __packed;
	50
492b49a2 AD	51	struct atpx_power_control {
	52	u16 size;
	53	u8 dgpu_state;
	54	} __packed;
	55
	56	struct atpx_mux {
	57	u16 size;
	58	u16 mux;
	59	} __packed;
	60
90c4cde9	61	bool radeon_has_atpx(void) {
10ebc0bc DA	62	return radeon_atpx_priv.atpx_detected;
	63	}
	64
48fa412b AD	65	/**
	66	* radeon_atpx_call - call an ATPX method
	67	*
	68	* @handle: acpi handle
	69	* @function: the ATPX function to execute
	70	* @params: ATPX function params
	71	*
	72	* Executes the requested ATPX function (all asics).
	73	* Returns a pointer to the acpi output buffer.
	74	*/
	75	static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
	76	struct acpi_buffer *params)
6a9ee8af DA	77	{
6a9ee8af DA	78	acpi_status status;
48fa412b	79	union acpi_object atpx_arg_elements[2];
6a9ee8af DA	80	struct acpi_object_list atpx_arg;
	81	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	82
	83	atpx_arg.count = 2;
	84	atpx_arg.pointer = &atpx_arg_elements[0];
	85
	86	atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
48fa412b AD	87	atpx_arg_elements[0].integer.value = function;
	88
	89	if (params) {
	90	atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
	91	atpx_arg_elements[1].buffer.length = params->length;
	92	atpx_arg_elements[1].buffer.pointer = params->pointer;
	93	} else {
	94	/* We need a second fake parameter */
	95	atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
	96	atpx_arg_elements[1].integer.value = 0;
	97	}
6a9ee8af	98
0b90365e	99	status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
6a9ee8af	100
48fa412b AD	101	/* Fail only if calling the method fails and ATPX is supported */
	102	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
	103	printk("failed to evaluate ATPX got %s\n",
	104	acpi_format_exception(status));
	105	kfree(buffer.pointer);
	106	return NULL;
6a9ee8af	107	}
48fa412b AD	108
	109	return buffer.pointer;
	110	}
	111
	112	/**
	113	* radeon_atpx_parse_functions - parse supported functions
	114	*
	115	* @f: supported functions struct
	116	* @mask: supported functions mask from ATPX
	117	*
	118	* Use the supported functions mask from ATPX function
	119	* ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
	120	* are supported (all asics).
	121	*/
	122	static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
	123	{
	124	f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
	125	f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
	126	f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
	127	f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
	128	f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
	129	f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
	130	f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
	131	f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
	132	}
	133
43a23aa4 AD	134	/**
	135	* radeon_atpx_validate_functions - validate ATPX functions
	136	*
	137	* @atpx: radeon atpx struct
	138	*
	139	* Validate that required functions are enabled (all asics).
	140	* returns 0 on success, error on failure.
	141	*/
	142	static int radeon_atpx_validate(struct radeon_atpx *atpx)
	143	{
	144	/* make sure required functions are enabled */
	145	/* dGPU power control is required */
	146	atpx->functions.power_cntl = true;
	147
	148	if (atpx->functions.px_params) {
	149	union acpi_object *info;
	150	struct atpx_px_params output;
	151	size_t size;
	152	u32 valid_bits;
	153
	154	info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
	155	if (!info)
	156	return -EIO;
	157
	158	memset(&output, 0, sizeof(output));
	159
	160	size = (u16 ) info->buffer.pointer;
	161	if (size < 10) {
	162	printk("ATPX buffer is too small: %zu\n", size);
	163	kfree(info);
	164	return -EINVAL;
	165	}
	166	size = min(sizeof(output), size);
	167
	168	memcpy(&output, info->buffer.pointer, size);
	169
	170	valid_bits = output.flags & output.valid_flags;
	171	/* if separate mux flag is set, mux controls are required */
	172	if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
	173	atpx->functions.i2c_mux_cntl = true;
	174	atpx->functions.disp_mux_cntl = true;
	175	}
	176	/* if any outputs are muxed, mux controls are required */
	177	if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED \|
	178	ATPX_TV_SIGNAL_MUXED \|
	179	ATPX_DFP_SIGNAL_MUXED))
	180	atpx->functions.disp_mux_cntl = true;
	181
	182	kfree(info);
	183	}
	184	return 0;
	185	}
	186
48fa412b AD	187	/**
	188	* radeon_atpx_verify_interface - verify ATPX
	189	*
48fa412b AD	190	* @atpx: radeon atpx struct
	191	*
	192	* Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
	193	* to initialize ATPX and determine what features are supported
	194	* (all asics).
	195	* returns 0 on success, error on failure.
	196	*/
492b49a2	197	static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
48fa412b AD	198	{
	199	union acpi_object *info;
	200	struct atpx_verify_interface output;
	201	size_t size;
	202	int err = 0;
	203
492b49a2	204	info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
48fa412b AD	205	if (!info)
	206	return -EIO;
	207
	208	memset(&output, 0, sizeof(output));
	209
	210	size = (u16 ) info->buffer.pointer;
	211	if (size < 8) {
bd6126bd	212	printk("ATPX buffer is too small: %zu\n", size);
48fa412b AD	213	err = -EINVAL;
	214	goto out;
	215	}
	216	size = min(sizeof(output), size);
	217
	218	memcpy(&output, info->buffer.pointer, size);
	219
	220	/* TODO: check version? */
9f050c7f AD	221	printk("ATPX version %u, functions 0x%08x\n",
9f050c7f AD	222	output.version, output.function_bits);
48fa412b AD	223
	224	radeon_atpx_parse_functions(&atpx->functions, output.function_bits);
	225
	226	out:
	227	kfree(info);
	228	return err;
6a9ee8af DA	229	}
6a9ee8af DA	230
82e02935 AD	231	/**
	232	* radeon_atpx_set_discrete_state - power up/down discrete GPU
	233	*
	234	* @atpx: atpx info struct
	235	* @state: discrete GPU state (0 = power down, 1 = power up)
	236	*
	237	* Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
	238	* power down/up the discrete GPU (all asics).
	239	* Returns 0 on success, error on failure.
	240	*/
492b49a2	241	static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
6a9ee8af	242	{
492b49a2 AD	243	struct acpi_buffer params;
	244	union acpi_object *info;
	245	struct atpx_power_control input;
	246
	247	if (atpx->functions.power_cntl) {
	248	input.size = 3;
	249	input.dgpu_state = state;
	250	params.length = input.size;
	251	params.pointer = &input;
	252	info = radeon_atpx_call(atpx->handle,
	253	ATPX_FUNCTION_POWER_CONTROL,
	254	&params);
	255	if (!info)
	256	return -EIO;
	257	kfree(info);
6a9ee8af	258	}
6a9ee8af DA	259	return 0;
	260	}
	261
82e02935 AD	262	/**
	263	* radeon_atpx_switch_disp_mux - switch display mux
	264	*
	265	* @atpx: atpx info struct
	266	* @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
	267	*
	268	* Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
	269	* switch the display mux between the discrete GPU and integrated GPU
	270	* (all asics).
	271	* Returns 0 on success, error on failure.
	272	*/
492b49a2	273	static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
6a9ee8af	274	{
492b49a2 AD	275	struct acpi_buffer params;
	276	union acpi_object *info;
	277	struct atpx_mux input;
	278
	279	if (atpx->functions.disp_mux_cntl) {
	280	input.size = 4;
	281	input.mux = mux_id;
	282	params.length = input.size;
	283	params.pointer = &input;
	284	info = radeon_atpx_call(atpx->handle,
	285	ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
	286	&params);
	287	if (!info)
	288	return -EIO;
	289	kfree(info);
	290	}
	291	return 0;
6a9ee8af DA	292	}
6a9ee8af DA	293
82e02935 AD	294	/**
	295	* radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
	296	*
	297	* @atpx: atpx info struct
	298	* @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
	299	*
	300	* Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
	301	* switch the i2c/hpd mux between the discrete GPU and integrated GPU
	302	* (all asics).
	303	* Returns 0 on success, error on failure.
	304	*/
492b49a2	305	static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
58e73811	306	{
492b49a2 AD	307	struct acpi_buffer params;
	308	union acpi_object *info;
	309	struct atpx_mux input;
	310
	311	if (atpx->functions.i2c_mux_cntl) {
	312	input.size = 4;
	313	input.mux = mux_id;
	314	params.length = input.size;
	315	params.pointer = &input;
	316	info = radeon_atpx_call(atpx->handle,
	317	ATPX_FUNCTION_I2C_MUX_CONTROL,
	318	&params);
	319	if (!info)
	320	return -EIO;
	321	kfree(info);
	322	}
	323	return 0;
58e73811 AD	324	}
58e73811 AD	325
82e02935 AD	326	/**
	327	* radeon_atpx_switch_start - notify the sbios of a GPU switch
	328	*
	329	* @atpx: atpx info struct
	330	* @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
	331	*
	332	* Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
	333	* function to notify the sbios that a switch between the discrete GPU and
	334	* integrated GPU has begun (all asics).
	335	* Returns 0 on success, error on failure.
	336	*/
492b49a2	337	static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
58e73811	338	{
492b49a2 AD	339	struct acpi_buffer params;
	340	union acpi_object *info;
	341	struct atpx_mux input;
	342
	343	if (atpx->functions.switch_start) {
	344	input.size = 4;
	345	input.mux = mux_id;
	346	params.length = input.size;
	347	params.pointer = &input;
	348	info = radeon_atpx_call(atpx->handle,
	349	ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
	350	&params);
	351	if (!info)
	352	return -EIO;
	353	kfree(info);
	354	}
	355	return 0;
58e73811 AD	356	}
58e73811 AD	357
82e02935 AD	358	/**
	359	* radeon_atpx_switch_end - notify the sbios of a GPU switch
	360	*
	361	* @atpx: atpx info struct
	362	* @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
	363	*
	364	* Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
	365	* function to notify the sbios that a switch between the discrete GPU and
	366	* integrated GPU has ended (all asics).
	367	* Returns 0 on success, error on failure.
	368	*/
492b49a2	369	static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
58e73811	370	{
492b49a2 AD	371	struct acpi_buffer params;
	372	union acpi_object *info;
	373	struct atpx_mux input;
	374
	375	if (atpx->functions.switch_end) {
	376	input.size = 4;
	377	input.mux = mux_id;
	378	params.length = input.size;
	379	params.pointer = &input;
	380	info = radeon_atpx_call(atpx->handle,
	381	ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
	382	&params);
	383	if (!info)
	384	return -EIO;
	385	kfree(info);
	386	}
	387	return 0;
58e73811	388	}
6a9ee8af	389
82e02935 AD	390	/**
	391	* radeon_atpx_switchto - switch to the requested GPU
	392	*
	393	* @id: GPU to switch to
	394	*
	395	* Execute the necessary ATPX functions to switch between the discrete GPU and
	396	* integrated GPU (all asics).
	397	* Returns 0 on success, error on failure.
	398	*/
6a9ee8af DA	399	static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
6a9ee8af DA	400	{
492b49a2	401	u16 gpu_id;
58e73811	402
6a9ee8af	403	if (id == VGA_SWITCHEROO_IGD)
9e05b2f4	404	gpu_id = ATPX_INTEGRATED_GPU;
6a9ee8af	405	else
9e05b2f4	406	gpu_id = ATPX_DISCRETE_GPU;
58e73811	407
492b49a2 AD	408	radeon_atpx_switch_start(&radeon_atpx_priv.atpx, gpu_id);
	409	radeon_atpx_switch_disp_mux(&radeon_atpx_priv.atpx, gpu_id);
	410	radeon_atpx_switch_i2c_mux(&radeon_atpx_priv.atpx, gpu_id);
	411	radeon_atpx_switch_end(&radeon_atpx_priv.atpx, gpu_id);
58e73811	412
6a9ee8af DA	413	return 0;
	414	}
	415
82e02935	416	/**
dfdcbebc	417	* radeon_atpx_power_state - power down/up the requested GPU
82e02935	418	*
dfdcbebc	419	* @id: GPU to power down/up
82e02935 AD	420	* @state: requested power state (0 = off, 1 = on)
	421	*
	422	* Execute the necessary ATPX function to power down/up the discrete GPU
	423	* (all asics).
	424	* Returns 0 on success, error on failure.
	425	*/
6a9ee8af DA	426	static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
	427	enum vga_switcheroo_state state)
	428	{
	429	/* on w500 ACPI can't change intel gpu state */
	430	if (id == VGA_SWITCHEROO_IGD)
	431	return 0;
	432
492b49a2	433	radeon_atpx_set_discrete_state(&radeon_atpx_priv.atpx, state);
6a9ee8af DA	434	return 0;
	435	}
	436
82e02935	437	/**
c9bd773c	438	* radeon_atpx_pci_probe_handle - look up the ATPX handle
82e02935 AD	439	*
	440	* @pdev: pci device
	441	*
c9bd773c	442	* Look up the ATPX handles (all asics).
82e02935 AD	443	* Returns true if the handles are found, false if not.
82e02935 AD	444	*/
6a9ee8af DA	445	static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
6a9ee8af DA	446	{
c61e2775	447	acpi_handle dhandle, atpx_handle;
6a9ee8af DA	448	acpi_status status;
6a9ee8af DA	449
3a83f992	450	dhandle = ACPI_HANDLE(&pdev->dev);
6a9ee8af DA	451	if (!dhandle)
	452	return false;
	453
	454	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
f91ce35e	455	if (ACPI_FAILURE(status))
6a9ee8af	456	return false;
f91ce35e	457
6a9ee8af	458	radeon_atpx_priv.dhandle = dhandle;
492b49a2	459	radeon_atpx_priv.atpx.handle = atpx_handle;
6a9ee8af DA	460	return true;
	461	}
	462
82e02935 AD	463	/**
	464	* radeon_atpx_init - verify the ATPX interface
	465	*
	466	* Verify the ATPX interface (all asics).
	467	* Returns 0 on success, error on failure.
	468	*/
6a9ee8af DA	469	static int radeon_atpx_init(void)
6a9ee8af DA	470	{
43a23aa4 AD	471	int r;
43a23aa4 AD	472
6a9ee8af	473	/* set up the ATPX handle */
43a23aa4 AD	474	r = radeon_atpx_verify_interface(&radeon_atpx_priv.atpx);
	475	if (r)
	476	return r;
	477
	478	/* validate the atpx setup */
	479	r = radeon_atpx_validate(&radeon_atpx_priv.atpx);
	480	if (r)
	481	return r;
	482
	483	return 0;
6a9ee8af DA	484	}
6a9ee8af DA	485
82e02935 AD	486	/**
	487	* radeon_atpx_get_client_id - get the client id
	488	*
	489	* @pdev: pci device
	490	*
	491	* look up whether we are the integrated or discrete GPU (all asics).
	492	* Returns the client id.
	493	*/
6a9ee8af DA	494	static int radeon_atpx_get_client_id(struct pci_dev *pdev)
6a9ee8af DA	495	{
3a83f992	496	if (radeon_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
6a9ee8af DA	497	return VGA_SWITCHEROO_IGD;
	498	else
	499	return VGA_SWITCHEROO_DIS;
	500	}
	501
5d170139	502	static const struct vga_switcheroo_handler radeon_atpx_handler = {
6a9ee8af DA	503	.switchto = radeon_atpx_switchto,
	504	.power_state = radeon_atpx_power_state,
	505	.init = radeon_atpx_init,
	506	.get_client_id = radeon_atpx_get_client_id,
	507	};
	508
82e02935 AD	509	/**
	510	* radeon_atpx_detect - detect whether we have PX
	511	*
	512	* Check if we have a PX system (all asics).
	513	* Returns true if we have a PX system, false if not.
	514	*/
6a9ee8af DA	515	static bool radeon_atpx_detect(void)
	516	{
	517	char acpi_method_name[255] = { 0 };
	518	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
	519	struct pci_dev *pdev = NULL;
	520	bool has_atpx = false;
	521	int vga_count = 0;
	522
	523	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
	524	vga_count++;
	525
	526	has_atpx \|= (radeon_atpx_pci_probe_handle(pdev) == true);
	527	}
	528
e9a4099a AD	529	/* some newer PX laptops mark the dGPU as a non-VGA display device */
	530	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
	531	vga_count++;
	532
	533	has_atpx \|= (radeon_atpx_pci_probe_handle(pdev) == true);
	534	}
	535
6a9ee8af	536	if (has_atpx && vga_count == 2) {
492b49a2	537	acpi_get_name(radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
8e5de1d8	538	printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
6a9ee8af DA	539	acpi_method_name);
	540	radeon_atpx_priv.atpx_detected = true;
	541	return true;
	542	}
	543	return false;
	544	}
	545
82e02935 AD	546	/**
	547	* radeon_register_atpx_handler - register with vga_switcheroo
	548	*
	549	* Register the PX callbacks with vga_switcheroo (all asics).
	550	*/
6a9ee8af DA	551	void radeon_register_atpx_handler(void)
	552	{
	553	bool r;
156d7d41	554	enum vga_switcheroo_handler_flags_t handler_flags = 0;
6a9ee8af DA	555
	556	/* detect if we have any ATPX + 2 VGA in the system */
	557	r = radeon_atpx_detect();
	558	if (!r)
	559	return;
	560
156d7d41	561	vga_switcheroo_register_handler(&radeon_atpx_handler, handler_flags);
6a9ee8af DA	562	}
6a9ee8af DA	563
82e02935 AD	564	/**
	565	* radeon_unregister_atpx_handler - unregister with vga_switcheroo
	566	*
	567	* Unregister the PX callbacks with vga_switcheroo (all asics).
	568	*/
6a9ee8af DA	569	void radeon_unregister_atpx_handler(void)
	570	{
	571	vga_switcheroo_unregister_handler();
	572	}