[mirror_ubuntu-bionic-kernel.git] / drivers / gpu / drm / i915 / intel_dp_aux_backlight.c

/*
 * Copyright © 2015 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include "intel_drv.h"

static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable)
{
	uint8_t reg_val = 0;

	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER,
			      &reg_val) < 0) {
		DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
			      DP_EDP_DISPLAY_CONTROL_REGISTER);
		return;
	}
	if (enable)
		reg_val |= DP_EDP_BACKLIGHT_ENABLE;
	else
		reg_val &= ~(DP_EDP_BACKLIGHT_ENABLE);

	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER,
			       reg_val) != 1) {
		DRM_DEBUG_KMS("Failed to %s aux backlight\n",
			      enable ? "enable" : "disable");
	}
}

/*
 * Read the current backlight value from DPCD register(s) based
 * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported
 */
static uint32_t intel_dp_aux_get_backlight(struct intel_connector *connector)
{
	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	uint8_t read_val[2] = { 0x0 };
	uint16_t level = 0;

	if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB,
			     &read_val, sizeof(read_val)) < 0) {
		DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
			      DP_EDP_BACKLIGHT_BRIGHTNESS_MSB);
		return 0;
	}
	level = read_val[0];
	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT)
		level = (read_val[0] << 8 | read_val[1]);

	return level;
}

/*
 * Sends the current backlight level over the aux channel, checking if its using
 * 8-bit or 16 bit value (MSB and LSB)
 */
static void
intel_dp_aux_set_backlight(struct intel_connector *connector, u32 level)
{
	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	uint8_t vals[2] = { 0x0 };

	vals[0] = level;

	/* Write the MSB and/or LSB */
	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) {
		vals[0] = (level & 0xFF00) >> 8;
		vals[1] = (level & 0xFF);
	}
	if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB,
			      vals, sizeof(vals)) < 0) {
		DRM_DEBUG_KMS("Failed to write aux backlight level\n");
		return;
	}
}

static void intel_dp_aux_enable_backlight(struct intel_connector *connector)
{
	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	uint8_t dpcd_buf = 0;
	uint8_t edp_backlight_mode = 0;

	set_aux_backlight_enable(intel_dp, true);

	if (drm_dp_dpcd_readb(&intel_dp->aux,
			DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf) != 1) {
		DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
			      DP_EDP_BACKLIGHT_MODE_SET_REGISTER);
		return;
	}

	edp_backlight_mode = dpcd_buf & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK;

	switch (edp_backlight_mode) {
	case DP_EDP_BACKLIGHT_CONTROL_MODE_PWM:
	case DP_EDP_BACKLIGHT_CONTROL_MODE_PRESET:
	case DP_EDP_BACKLIGHT_CONTROL_MODE_PRODUCT:
		dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK;
		dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
		if (drm_dp_dpcd_writeb(&intel_dp->aux,
			DP_EDP_BACKLIGHT_MODE_SET_REGISTER, dpcd_buf) < 0) {
			DRM_DEBUG_KMS("Failed to write aux backlight mode\n");
		}
		break;

	/* Do nothing when it is already DPCD mode */
	case DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD:
	default:
		break;
	}
}

static void intel_dp_aux_disable_backlight(struct intel_connector *connector)
{
	set_aux_backlight_enable(enc_to_intel_dp(&connector->encoder->base), false);
}

static int intel_dp_aux_setup_backlight(struct intel_connector *connector,
					enum pipe pipe)
{
	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	struct intel_panel *panel = &connector->panel;

	intel_dp_aux_enable_backlight(connector);

	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT)
		panel->backlight.max = 0xFFFF;
	else
		panel->backlight.max = 0xFF;

	panel->backlight.min = 0;
	panel->backlight.level = intel_dp_aux_get_backlight(connector);

	panel->backlight.enabled = panel->backlight.level != 0;

	return 0;
}

static bool
intel_dp_aux_display_control_capable(struct intel_connector *connector)
{
	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);

	/* Check the  eDP Display control capabilities registers to determine if
	 * the panel can support backlight control over the aux channel
	 */
	if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP &&
	    (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
	    (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) &&
	    !((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_PIN_ENABLE_CAP) ||
	      (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP))) {
		DRM_DEBUG_KMS("AUX Backlight Control Supported!\n");
		return true;
	}
	return false;
}

int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector)
{
	struct intel_panel *panel = &intel_connector->panel;

	if (!i915.enable_dpcd_backlight)
		return -ENODEV;

	if (!intel_dp_aux_display_control_capable(intel_connector))
		return -ENODEV;

	panel->backlight.setup = intel_dp_aux_setup_backlight;
	panel->backlight.enable = intel_dp_aux_enable_backlight;
	panel->backlight.disable = intel_dp_aux_disable_backlight;
	panel->backlight.set = intel_dp_aux_set_backlight;
	panel->backlight.get = intel_dp_aux_get_backlight;

	return 0;
}
Commit	Line	Data
e7156c83 YA	1	/*
	2	* Copyright © 2015 Intel Corporation
	3	*
	4	* Permission is hereby granted, free of charge, to any person obtaining a
	5	* copy of this software and associated documentation files (the "Software"),
	6	* to deal in the Software without restriction, including without limitation
	7	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	8	* and/or sell copies of the Software, and to permit persons to whom the
	9	* Software is furnished to do so, subject to the following conditions:
	10	*
	11	* The above copyright notice and this permission notice (including the next
	12	* paragraph) shall be included in all copies or substantial portions of the
	13	* Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	19	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	20	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	21	* IN THE SOFTWARE.
	22	*
	23	*/
	24
	25	#include "intel_drv.h"
	26
	27	static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable)
	28	{
	29	uint8_t reg_val = 0;
	30
	31	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER,
	32	&reg_val) < 0) {
	33	DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
	34	DP_EDP_DISPLAY_CONTROL_REGISTER);
	35	return;
	36	}
	37	if (enable)
	38	reg_val \|= DP_EDP_BACKLIGHT_ENABLE;
	39	else
	40	reg_val &= ~(DP_EDP_BACKLIGHT_ENABLE);
	41
	42	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER,
	43	reg_val) != 1) {
	44	DRM_DEBUG_KMS("Failed to %s aux backlight\n",
	45	enable ? "enable" : "disable");
	46	}
	47	}
	48
	49	/*
	50	* Read the current backlight value from DPCD register(s) based
	51	* on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported
	52	*/
	53	static uint32_t intel_dp_aux_get_backlight(struct intel_connector *connector)
	54	{
	55	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	56	uint8_t read_val[2] = { 0x0 };
	57	uint16_t level = 0;
	58
	59	if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB,
	60	&read_val, sizeof(read_val)) < 0) {
	61	DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
	62	DP_EDP_BACKLIGHT_BRIGHTNESS_MSB);
	63	return 0;
	64	}
65	level = read_val[0];
66	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT)
67	level = (read_val[0] << 8 \| read_val[1]);
68
69	return level;
70	}
71
72	/*
73	* Sends the current backlight level over the aux channel, checking if its using
74	* 8-bit or 16 bit value (MSB and LSB)
75	*/
76	static void
77	intel_dp_aux_set_backlight(struct intel_connector *connector, u32 level)
78	{
79	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
80	uint8_t vals[2] = { 0x0 };
81
82	vals[0] = level;
83
84	/* Write the MSB and/or LSB */
85	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) {
86	vals[0] = (level & 0xFF00) >> 8;
87	vals[1] = (level & 0xFF);
88	}
89	if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB,
90	vals, sizeof(vals)) < 0) {
91	DRM_DEBUG_KMS("Failed to write aux backlight level\n");
92	return;
93	}
94	}
95
96	static void intel_dp_aux_enable_backlight(struct intel_connector *connector)
97	{
98	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
99	uint8_t dpcd_buf = 0;
73ab484c	100	uint8_t edp_backlight_mode = 0;
e7156c83 YA	101
	102	set_aux_backlight_enable(intel_dp, true);
	103
73ab484c PV	104	if (drm_dp_dpcd_readb(&intel_dp->aux,
	105	DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf) != 1) {
	106	DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
	107	DP_EDP_BACKLIGHT_MODE_SET_REGISTER);
	108	return;
	109	}
	110
	111	edp_backlight_mode = dpcd_buf & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK;
	112
	113	switch (edp_backlight_mode) {
	114	case DP_EDP_BACKLIGHT_CONTROL_MODE_PWM:
	115	case DP_EDP_BACKLIGHT_CONTROL_MODE_PRESET:
	116	case DP_EDP_BACKLIGHT_CONTROL_MODE_PRODUCT:
	117	dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK;
	118	dpcd_buf \|= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
	119	if (drm_dp_dpcd_writeb(&intel_dp->aux,
	120	DP_EDP_BACKLIGHT_MODE_SET_REGISTER, dpcd_buf) < 0) {
	121	DRM_DEBUG_KMS("Failed to write aux backlight mode\n");
	122	}
	123	break;
	124
	125	/* Do nothing when it is already DPCD mode */
	126	case DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD:
	127	default:
	128	break;
	129	}
e7156c83 YA	130	}
	131
	132	static void intel_dp_aux_disable_backlight(struct intel_connector *connector)
	133	{
	134	set_aux_backlight_enable(enc_to_intel_dp(&connector->encoder->base), false);
	135	}
	136
	137	static int intel_dp_aux_setup_backlight(struct intel_connector *connector,
	138	enum pipe pipe)
	139	{
	140	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	141	struct intel_panel *panel = &connector->panel;
	142
	143	intel_dp_aux_enable_backlight(connector);
	144
	145	if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT)
	146	panel->backlight.max = 0xFFFF;
	147	else
	148	panel->backlight.max = 0xFF;
	149
	150	panel->backlight.min = 0;
	151	panel->backlight.level = intel_dp_aux_get_backlight(connector);
	152
	153	panel->backlight.enabled = panel->backlight.level != 0;
	154
	155	return 0;
	156	}
	157
	158	static bool
	159	intel_dp_aux_display_control_capable(struct intel_connector *connector)
	160	{
	161	struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base);
	162
	163	/* Check the eDP Display control capabilities registers to determine if
	164	* the panel can support backlight control over the aux channel
	165	*/
	166	if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP &&
	167	(intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
a644ca9b	168	(intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) &&
e7156c83 YA	169	!((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_PIN_ENABLE_CAP) \|\|
	170	(intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP))) {
	171	DRM_DEBUG_KMS("AUX Backlight Control Supported!\n");
	172	return true;
	173	}
	174	return false;
	175	}
	176
	177	int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector)
	178	{
	179	struct intel_panel *panel = &intel_connector->panel;
	180
	181	if (!i915.enable_dpcd_backlight)
	182	return -ENODEV;
	183
	184	if (!intel_dp_aux_display_control_capable(intel_connector))
	185	return -ENODEV;
	186
	187	panel->backlight.setup = intel_dp_aux_setup_backlight;
	188	panel->backlight.enable = intel_dp_aux_enable_backlight;
	189	panel->backlight.disable = intel_dp_aux_disable_backlight;
	190	panel->backlight.set = intel_dp_aux_set_backlight;
	191	panel->backlight.get = intel_dp_aux_get_backlight;
	192
	193	return 0;
	194	}