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 /*
26 * Laptops with Intel GPUs which have panels that support controlling the
27 * backlight through DP AUX can actually use two different interfaces: Intel's
28 * proprietary DP AUX backlight interface, and the standard VESA backlight
29 * interface. Unfortunately, at the time of writing this a lot of laptops will
30 * advertise support for the standard VESA backlight interface when they
31 * don't properly support it. However, on these systems the Intel backlight
32 * interface generally does work properly. Additionally, these systems will
33 * usually just indicate that they use PWM backlight controls in their VBIOS
34 * for some reason.
35 */
36
37 #include "intel_display_types.h"
38 #include "intel_dp_aux_backlight.h"
39 #include "intel_panel.h"
40
41 /* TODO:
42 * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we
43 * can make people's backlights work in the mean time
44 */
45
46 /*
47 * DP AUX registers for Intel's proprietary HDR backlight interface. We define
48 * them here since we'll likely be the only driver to ever use these.
49 */
50 #define INTEL_EDP_HDR_TCON_CAP0 0x340
51
52 #define INTEL_EDP_HDR_TCON_CAP1 0x341
53 # define INTEL_EDP_HDR_TCON_2084_DECODE_CAP BIT(0)
54 # define INTEL_EDP_HDR_TCON_2020_GAMUT_CAP BIT(1)
55 # define INTEL_EDP_HDR_TCON_TONE_MAPPING_CAP BIT(2)
56 # define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_CAP BIT(3)
57 # define INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP BIT(4)
58 # define INTEL_EDP_HDR_TCON_OPTIMIZATION_CAP BIT(5)
59 # define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_CAP BIT(6)
60 # define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_CONVERSION_CAP BIT(7)
61
62 #define INTEL_EDP_HDR_TCON_CAP2 0x342
63 # define INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP BIT(0)
64
65 #define INTEL_EDP_HDR_TCON_CAP3 0x343
66
67 #define INTEL_EDP_HDR_GETSET_CTRL_PARAMS 0x344
68 # define INTEL_EDP_HDR_TCON_2084_DECODE_ENABLE BIT(0)
69 # define INTEL_EDP_HDR_TCON_2020_GAMUT_ENABLE BIT(1)
70 # define INTEL_EDP_HDR_TCON_TONE_MAPPING_ENABLE BIT(2) /* Pre-TGL+ */
71 # define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_ENABLE BIT(3)
72 # define INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE BIT(4)
73 # define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_ENABLE BIT(5)
74 /* Bit 6 is reserved */
75 # define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_ENABLE BIT(7)
76
77 #define INTEL_EDP_HDR_CONTENT_LUMINANCE 0x346 /* Pre-TGL+ */
78 #define INTEL_EDP_HDR_PANEL_LUMINANCE_OVERRIDE 0x34A
79 #define INTEL_EDP_SDR_LUMINANCE_LEVEL 0x352
80 #define INTEL_EDP_BRIGHTNESS_NITS_LSB 0x354
81 #define INTEL_EDP_BRIGHTNESS_NITS_MSB 0x355
82 #define INTEL_EDP_BRIGHTNESS_DELAY_FRAMES 0x356
83 #define INTEL_EDP_BRIGHTNESS_PER_FRAME_STEPS 0x357
84
85 #define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_0 0x358
86 # define INTEL_EDP_TCON_USAGE_MASK GENMASK(0, 3)
87 # define INTEL_EDP_TCON_USAGE_UNKNOWN 0x0
88 # define INTEL_EDP_TCON_USAGE_DESKTOP 0x1
89 # define INTEL_EDP_TCON_USAGE_FULL_SCREEN_MEDIA 0x2
90 # define INTEL_EDP_TCON_USAGE_FULL_SCREEN_GAMING 0x3
91 # define INTEL_EDP_TCON_POWER_MASK BIT(4)
92 # define INTEL_EDP_TCON_POWER_DC (0 << 4)
93 # define INTEL_EDP_TCON_POWER_AC (1 << 4)
94 # define INTEL_EDP_TCON_OPTIMIZATION_STRENGTH_MASK GENMASK(5, 7)
95
96 #define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_1 0x359
97
98 /* Intel EDP backlight callbacks */
99 static bool
intel_dp_aux_supports_hdr_backlight(struct intel_connector * connector)100 intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector)
101 {
102 struct drm_i915_private *i915 = to_i915(connector->base.dev);
103 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
104 struct drm_dp_aux *aux = &intel_dp->aux;
105 struct intel_panel *panel = &connector->panel;
106 int ret;
107 u8 tcon_cap[4];
108
109 ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, tcon_cap, sizeof(tcon_cap));
110 if (ret != sizeof(tcon_cap))
111 return false;
112
113 if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP))
114 return false;
115
116 if (tcon_cap[0] >= 1) {
117 drm_dbg_kms(&i915->drm, "Detected Intel HDR backlight interface version %d\n",
118 tcon_cap[0]);
119 } else {
120 drm_dbg_kms(&i915->drm, "Detected unsupported HDR backlight interface version %d\n",
121 tcon_cap[0]);
122 return false;
123 }
124
125 panel->backlight.edp.intel.sdr_uses_aux =
126 tcon_cap[2] & INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP;
127
128 return true;
129 }
130
131 static u32
intel_dp_aux_hdr_get_backlight(struct intel_connector * connector,enum pipe pipe)132 intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe)
133 {
134 struct drm_i915_private *i915 = to_i915(connector->base.dev);
135 struct intel_panel *panel = &connector->panel;
136 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
137 u8 tmp;
138 u8 buf[2] = { 0 };
139
140 if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) != 1) {
141 drm_err(&i915->drm, "Failed to read current backlight mode from DPCD\n");
142 return 0;
143 }
144
145 if (!(tmp & INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE)) {
146 if (!panel->backlight.edp.intel.sdr_uses_aux) {
147 u32 pwm_level = panel->backlight.pwm_funcs->get(connector, pipe);
148
149 return intel_panel_backlight_level_from_pwm(connector, pwm_level);
150 }
151
152 /* Assume 100% brightness if backlight controls aren't enabled yet */
153 return panel->backlight.max;
154 }
155
156 if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf,
157 sizeof(buf)) != sizeof(buf)) {
158 drm_err(&i915->drm, "Failed to read brightness from DPCD\n");
159 return 0;
160 }
161
162 return (buf[1] << 8 | buf[0]);
163 }
164
165 static void
intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state * conn_state,u32 level)166 intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state *conn_state, u32 level)
167 {
168 struct intel_connector *connector = to_intel_connector(conn_state->connector);
169 struct drm_device *dev = connector->base.dev;
170 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
171 u8 buf[4] = { 0 };
172
173 buf[0] = level & 0xFF;
174 buf[1] = (level & 0xFF00) >> 8;
175
176 if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf,
177 sizeof(buf)) != sizeof(buf))
178 drm_err(dev, "Failed to write brightness level to DPCD\n");
179 }
180
181 static void
intel_dp_aux_hdr_set_backlight(const struct drm_connector_state * conn_state,u32 level)182 intel_dp_aux_hdr_set_backlight(const struct drm_connector_state *conn_state, u32 level)
183 {
184 struct intel_connector *connector = to_intel_connector(conn_state->connector);
185 struct intel_panel *panel = &connector->panel;
186
187 if (panel->backlight.edp.intel.sdr_uses_aux) {
188 intel_dp_aux_hdr_set_aux_backlight(conn_state, level);
189 } else {
190 const u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level);
191
192 intel_panel_set_pwm_level(conn_state, pwm_level);
193 }
194 }
195
196 static void
intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state * crtc_state,const struct drm_connector_state * conn_state,u32 level)197 intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state,
198 const struct drm_connector_state *conn_state, u32 level)
199 {
200 struct intel_connector *connector = to_intel_connector(conn_state->connector);
201 struct intel_panel *panel = &connector->panel;
202 struct drm_i915_private *i915 = to_i915(connector->base.dev);
203 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
204 int ret;
205 u8 old_ctrl, ctrl;
206
207 ret = drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &old_ctrl);
208 if (ret != 1) {
209 drm_err(&i915->drm, "Failed to read current backlight control mode: %d\n", ret);
210 return;
211 }
212
213 ctrl = old_ctrl;
214 if (panel->backlight.edp.intel.sdr_uses_aux) {
215 ctrl |= INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE;
216 intel_dp_aux_hdr_set_aux_backlight(conn_state, level);
217 } else {
218 u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level);
219
220 panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level);
221
222 ctrl &= ~INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE;
223 }
224
225 if (ctrl != old_ctrl)
226 if (drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) != 1)
227 drm_err(&i915->drm, "Failed to configure DPCD brightness controls\n");
228 }
229
230 static void
intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state * conn_state,u32 level)231 intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
232 {
233 struct intel_connector *connector = to_intel_connector(conn_state->connector);
234 struct intel_panel *panel = &connector->panel;
235
236 /* Nothing to do for AUX based backlight controls */
237 if (panel->backlight.edp.intel.sdr_uses_aux)
238 return;
239
240 /* Note we want the actual pwm_level to be 0, regardless of pwm_min */
241 panel->backlight.pwm_funcs->disable(conn_state, intel_panel_invert_pwm_level(connector, 0));
242 }
243
244 static int
intel_dp_aux_hdr_setup_backlight(struct intel_connector * connector,enum pipe pipe)245 intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pipe)
246 {
247 struct drm_i915_private *i915 = to_i915(connector->base.dev);
248 struct intel_panel *panel = &connector->panel;
249 int ret;
250
251 if (panel->backlight.edp.intel.sdr_uses_aux) {
252 drm_dbg_kms(&i915->drm, "SDR backlight is controlled through DPCD\n");
253 } else {
254 drm_dbg_kms(&i915->drm, "SDR backlight is controlled through PWM\n");
255
256 ret = panel->backlight.pwm_funcs->setup(connector, pipe);
257 if (ret < 0) {
258 drm_err(&i915->drm,
259 "Failed to setup SDR backlight controls through PWM: %d\n", ret);
260 return ret;
261 }
262 }
263
264 panel->backlight.max = 512;
265 panel->backlight.min = 0;
266 panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector, pipe);
267 panel->backlight.enabled = panel->backlight.level != 0;
268
269 return 0;
270 }
271
272 /* VESA backlight callbacks */
intel_dp_aux_vesa_get_backlight(struct intel_connector * connector,enum pipe unused)273 static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, enum pipe unused)
274 {
275 return connector->panel.backlight.level;
276 }
277
278 static void
intel_dp_aux_vesa_set_backlight(const struct drm_connector_state * conn_state,u32 level)279 intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, u32 level)
280 {
281 struct intel_connector *connector = to_intel_connector(conn_state->connector);
282 struct intel_panel *panel = &connector->panel;
283 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
284
285 drm_edp_backlight_set_level(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
286 }
287
288 static void
intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state * crtc_state,const struct drm_connector_state * conn_state,u32 level)289 intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state,
290 const struct drm_connector_state *conn_state, u32 level)
291 {
292 struct intel_connector *connector = to_intel_connector(conn_state->connector);
293 struct intel_panel *panel = &connector->panel;
294 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
295
296 drm_edp_backlight_enable(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
297 }
298
intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state * old_conn_state,u32 level)299 static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state *old_conn_state,
300 u32 level)
301 {
302 struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
303 struct intel_panel *panel = &connector->panel;
304 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
305
306 drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info);
307 }
308
intel_dp_aux_vesa_setup_backlight(struct intel_connector * connector,enum pipe pipe)309 static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, enum pipe pipe)
310 {
311 struct intel_dp *intel_dp = intel_attached_dp(connector);
312 struct intel_panel *panel = &connector->panel;
313 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
314 u16 current_level;
315 u8 current_mode;
316 int ret;
317
318 ret = drm_edp_backlight_init(&intel_dp->aux, &panel->backlight.edp.vesa.info,
319 i915->vbt.backlight.pwm_freq_hz, intel_dp->edp_dpcd,
320 ¤t_level, ¤t_mode);
321 if (ret < 0)
322 return ret;
323
324 panel->backlight.max = panel->backlight.edp.vesa.info.max;
325 panel->backlight.min = 0;
326 if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
327 panel->backlight.level = current_level;
328 panel->backlight.enabled = panel->backlight.level != 0;
329 } else {
330 panel->backlight.level = panel->backlight.max;
331 panel->backlight.enabled = false;
332 }
333
334 return 0;
335 }
336
337 static bool
intel_dp_aux_supports_vesa_backlight(struct intel_connector * connector)338 intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector)
339 {
340 struct intel_dp *intel_dp = intel_attached_dp(connector);
341 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
342
343 /* TODO: We currently only support AUX only backlight configurations, not backlights which
344 * require a mix of PWM and AUX controls to work. In the mean time, these machines typically
345 * work just fine using normal PWM controls anyway.
346 */
347 if ((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
348 drm_edp_backlight_supported(intel_dp->edp_dpcd)) {
349 drm_dbg_kms(&i915->drm, "AUX Backlight Control Supported!\n");
350 return true;
351 }
352 return false;
353 }
354
355 static const struct intel_panel_bl_funcs intel_dp_hdr_bl_funcs = {
356 .setup = intel_dp_aux_hdr_setup_backlight,
357 .enable = intel_dp_aux_hdr_enable_backlight,
358 .disable = intel_dp_aux_hdr_disable_backlight,
359 .set = intel_dp_aux_hdr_set_backlight,
360 .get = intel_dp_aux_hdr_get_backlight,
361 };
362
363 static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = {
364 .setup = intel_dp_aux_vesa_setup_backlight,
365 .enable = intel_dp_aux_vesa_enable_backlight,
366 .disable = intel_dp_aux_vesa_disable_backlight,
367 .set = intel_dp_aux_vesa_set_backlight,
368 .get = intel_dp_aux_vesa_get_backlight,
369 };
370
371 enum intel_dp_aux_backlight_modparam {
372 INTEL_DP_AUX_BACKLIGHT_AUTO = -1,
373 INTEL_DP_AUX_BACKLIGHT_OFF = 0,
374 INTEL_DP_AUX_BACKLIGHT_ON = 1,
375 INTEL_DP_AUX_BACKLIGHT_FORCE_VESA = 2,
376 INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL = 3,
377 };
378
intel_dp_aux_init_backlight_funcs(struct intel_connector * connector)379 int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector)
380 {
381 struct drm_device *dev = connector->base.dev;
382 struct intel_panel *panel = &connector->panel;
383 struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
384 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
385 bool try_intel_interface = false, try_vesa_interface = false;
386
387 /* Check the VBT and user's module parameters to figure out which
388 * interfaces to probe
389 */
390 switch (i915->params.enable_dpcd_backlight) {
391 case INTEL_DP_AUX_BACKLIGHT_OFF:
392 return -ENODEV;
393 case INTEL_DP_AUX_BACKLIGHT_AUTO:
394 switch (i915->vbt.backlight.type) {
395 case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE:
396 try_vesa_interface = true;
397 break;
398 case INTEL_BACKLIGHT_DISPLAY_DDI:
399 try_intel_interface = true;
400 break;
401 default:
402 return -ENODEV;
403 }
404 break;
405 case INTEL_DP_AUX_BACKLIGHT_ON:
406 if (i915->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE)
407 try_intel_interface = true;
408
409 try_vesa_interface = true;
410 break;
411 case INTEL_DP_AUX_BACKLIGHT_FORCE_VESA:
412 try_vesa_interface = true;
413 break;
414 case INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL:
415 try_intel_interface = true;
416 break;
417 }
418
419 /*
420 * A lot of eDP panels in the wild will report supporting both the
421 * Intel proprietary backlight control interface, and the VESA
422 * backlight control interface. Many of these panels are liars though,
423 * and will only work with the Intel interface. So, always probe for
424 * that first.
425 */
426 if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) {
427 drm_dbg_kms(dev, "Using Intel proprietary eDP backlight controls\n");
428 panel->backlight.funcs = &intel_dp_hdr_bl_funcs;
429 return 0;
430 }
431
432 if (try_vesa_interface && intel_dp_aux_supports_vesa_backlight(connector)) {
433 drm_dbg_kms(dev, "Using VESA eDP backlight controls\n");
434 panel->backlight.funcs = &intel_dp_vesa_bl_funcs;
435 return 0;
436 }
437
438 return -ENODEV;
439 }
440
