xref: /linux/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 /*
2  * Copyright © 2016 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
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Author: Deepak M <m.deepak at intel.com>
24  */
25 
26 #include <drm/drm_mipi_dsi.h>
27 #include <video/mipi_display.h>
28 
29 #include "i915_drv.h"
30 #include "intel_display_types.h"
31 #include "intel_dsi.h"
32 #include "intel_dsi_dcs_backlight.h"
33 
34 #define CONTROL_DISPLAY_BCTRL		(1 << 5)
35 #define CONTROL_DISPLAY_DD		(1 << 3)
36 #define CONTROL_DISPLAY_BL		(1 << 2)
37 
38 #define POWER_SAVE_OFF			(0 << 0)
39 #define POWER_SAVE_LOW			(1 << 0)
40 #define POWER_SAVE_MEDIUM		(2 << 0)
41 #define POWER_SAVE_HIGH			(3 << 0)
42 #define POWER_SAVE_OUTDOOR_MODE		(4 << 0)
43 
44 #define PANEL_PWM_MAX_VALUE		0xFF
45 
46 static u32 dcs_get_backlight(struct intel_connector *connector, enum pipe unused)
47 {
48 	struct intel_encoder *encoder = intel_attached_encoder(connector);
49 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
50 	struct intel_panel *panel = &connector->panel;
51 	struct mipi_dsi_device *dsi_device;
52 	u8 data[2] = {};
53 	enum port port;
54 	size_t len = panel->backlight.max > U8_MAX ? 2 : 1;
55 
56 	for_each_dsi_port(port, panel->vbt.dsi.bl_ports) {
57 		dsi_device = intel_dsi->dsi_hosts[port]->device;
58 		mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
59 				  &data, len);
60 		break;
61 	}
62 
63 	return (data[1] << 8) | data[0];
64 }
65 
66 static void dcs_set_backlight(const struct drm_connector_state *conn_state, u32 level)
67 {
68 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(to_intel_encoder(conn_state->best_encoder));
69 	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
70 	struct mipi_dsi_device *dsi_device;
71 	u8 data[2] = {};
72 	enum port port;
73 	size_t len = panel->backlight.max > U8_MAX ? 2 : 1;
74 	unsigned long mode_flags;
75 
76 	if (len == 1) {
77 		data[0] = level;
78 	} else {
79 		data[0] = level >> 8;
80 		data[1] = level;
81 	}
82 
83 	for_each_dsi_port(port, panel->vbt.dsi.bl_ports) {
84 		dsi_device = intel_dsi->dsi_hosts[port]->device;
85 		mode_flags = dsi_device->mode_flags;
86 		dsi_device->mode_flags &= ~MIPI_DSI_MODE_LPM;
87 		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
88 				   &data, len);
89 		dsi_device->mode_flags = mode_flags;
90 	}
91 }
92 
93 static void dcs_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
94 {
95 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(to_intel_encoder(conn_state->best_encoder));
96 	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
97 	struct mipi_dsi_device *dsi_device;
98 	enum port port;
99 
100 	dcs_set_backlight(conn_state, 0);
101 
102 	for_each_dsi_port(port, panel->vbt.dsi.cabc_ports) {
103 		u8 cabc = POWER_SAVE_OFF;
104 
105 		dsi_device = intel_dsi->dsi_hosts[port]->device;
106 		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
107 				   &cabc, sizeof(cabc));
108 	}
109 
110 	for_each_dsi_port(port, panel->vbt.dsi.bl_ports) {
111 		u8 ctrl = 0;
112 
113 		dsi_device = intel_dsi->dsi_hosts[port]->device;
114 
115 		mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_CONTROL_DISPLAY,
116 				  &ctrl, sizeof(ctrl));
117 
118 		ctrl &= ~CONTROL_DISPLAY_BL;
119 		ctrl &= ~CONTROL_DISPLAY_DD;
120 		ctrl &= ~CONTROL_DISPLAY_BCTRL;
121 
122 		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
123 				   &ctrl, sizeof(ctrl));
124 	}
125 }
126 
127 static void dcs_enable_backlight(const struct intel_crtc_state *crtc_state,
128 				 const struct drm_connector_state *conn_state, u32 level)
129 {
130 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(to_intel_encoder(conn_state->best_encoder));
131 	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
132 	struct mipi_dsi_device *dsi_device;
133 	enum port port;
134 
135 	for_each_dsi_port(port, panel->vbt.dsi.bl_ports) {
136 		u8 ctrl = 0;
137 
138 		dsi_device = intel_dsi->dsi_hosts[port]->device;
139 
140 		mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_CONTROL_DISPLAY,
141 				  &ctrl, sizeof(ctrl));
142 
143 		ctrl |= CONTROL_DISPLAY_BL;
144 		ctrl |= CONTROL_DISPLAY_DD;
145 		ctrl |= CONTROL_DISPLAY_BCTRL;
146 
147 		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
148 				   &ctrl, sizeof(ctrl));
149 	}
150 
151 	for_each_dsi_port(port, panel->vbt.dsi.cabc_ports) {
152 		u8 cabc = POWER_SAVE_MEDIUM;
153 
154 		dsi_device = intel_dsi->dsi_hosts[port]->device;
155 		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
156 				   &cabc, sizeof(cabc));
157 	}
158 
159 	dcs_set_backlight(conn_state, level);
160 }
161 
162 static int dcs_setup_backlight(struct intel_connector *connector,
163 			       enum pipe unused)
164 {
165 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
166 	struct intel_panel *panel = &connector->panel;
167 
168 	if (panel->vbt.backlight.brightness_precision_bits > 8)
169 		panel->backlight.max = (1 << panel->vbt.backlight.brightness_precision_bits) - 1;
170 	else
171 		panel->backlight.max = PANEL_PWM_MAX_VALUE;
172 
173 	panel->backlight.level = panel->backlight.max;
174 
175 	drm_dbg_kms(&i915->drm,
176 		    "[CONNECTOR:%d:%s] Using DCS for backlight control\n",
177 		    connector->base.base.id, connector->base.name);
178 
179 	return 0;
180 }
181 
182 static const struct intel_panel_bl_funcs dcs_bl_funcs = {
183 	.setup = dcs_setup_backlight,
184 	.enable = dcs_enable_backlight,
185 	.disable = dcs_disable_backlight,
186 	.set = dcs_set_backlight,
187 	.get = dcs_get_backlight,
188 };
189 
190 int intel_dsi_dcs_init_backlight_funcs(struct intel_connector *intel_connector)
191 {
192 	struct drm_device *dev = intel_connector->base.dev;
193 	struct intel_encoder *encoder = intel_attached_encoder(intel_connector);
194 	struct intel_panel *panel = &intel_connector->panel;
195 
196 	if (panel->vbt.backlight.type != INTEL_BACKLIGHT_DSI_DCS)
197 		return -ENODEV;
198 
199 	if (drm_WARN_ON(dev, encoder->type != INTEL_OUTPUT_DSI))
200 		return -EINVAL;
201 
202 	panel->backlight.funcs = &dcs_bl_funcs;
203 
204 	return 0;
205 }
206