1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2021 Intel Corporation
4  */
5 
6 #include <linux/backlight.h>
7 #include <linux/kernel.h>
8 #include <linux/pwm.h>
9 #include <linux/string_helpers.h>
10 
11 #include "i915_reg.h"
12 #include "intel_backlight.h"
13 #include "intel_backlight_regs.h"
14 #include "intel_connector.h"
15 #include "intel_de.h"
16 #include "intel_display_types.h"
17 #include "intel_dp_aux_backlight.h"
18 #include "intel_dsi_dcs_backlight.h"
19 #include "intel_panel.h"
20 #include "intel_pci_config.h"
21 #include "intel_pps.h"
22 #include "intel_quirks.h"
23 
24 /**
25  * scale - scale values from one range to another
26  * @source_val: value in range [@source_min..@source_max]
27  * @source_min: minimum legal value for @source_val
28  * @source_max: maximum legal value for @source_val
29  * @target_min: corresponding target value for @source_min
30  * @target_max: corresponding target value for @source_max
31  *
32  * Return @source_val in range [@source_min..@source_max] scaled to range
33  * [@target_min..@target_max].
34  */
35 static u32 scale(u32 source_val,
36 		 u32 source_min, u32 source_max,
37 		 u32 target_min, u32 target_max)
38 {
39 	u64 target_val;
40 
41 	WARN_ON(source_min > source_max);
42 	WARN_ON(target_min > target_max);
43 
44 	/* defensive */
45 	source_val = clamp(source_val, source_min, source_max);
46 
47 	/* avoid overflows */
48 	target_val = mul_u32_u32(source_val - source_min,
49 				 target_max - target_min);
50 	target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
51 	target_val += target_min;
52 
53 	return target_val;
54 }
55 
56 /*
57  * Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
58  * to [hw_min..hw_max].
59  */
60 static u32 clamp_user_to_hw(struct intel_connector *connector,
61 			    u32 user_level, u32 user_max)
62 {
63 	struct intel_panel *panel = &connector->panel;
64 	u32 hw_level;
65 
66 	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
67 	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
68 
69 	return hw_level;
70 }
71 
72 /* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
73 static u32 scale_hw_to_user(struct intel_connector *connector,
74 			    u32 hw_level, u32 user_max)
75 {
76 	struct intel_panel *panel = &connector->panel;
77 
78 	return scale(hw_level, panel->backlight.min, panel->backlight.max,
79 		     0, user_max);
80 }
81 
82 u32 intel_backlight_invert_pwm_level(struct intel_connector *connector, u32 val)
83 {
84 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
85 	struct intel_panel *panel = &connector->panel;
86 
87 	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
88 
89 	if (dev_priv->params.invert_brightness < 0)
90 		return val;
91 
92 	if (dev_priv->params.invert_brightness > 0 ||
93 	    intel_has_quirk(dev_priv, QUIRK_INVERT_BRIGHTNESS)) {
94 		return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
95 	}
96 
97 	return val;
98 }
99 
100 void intel_backlight_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
101 {
102 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
103 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
104 	struct intel_panel *panel = &connector->panel;
105 
106 	drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
107 	panel->backlight.pwm_funcs->set(conn_state, val);
108 }
109 
110 u32 intel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
111 {
112 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
113 	struct intel_panel *panel = &connector->panel;
114 
115 	drm_WARN_ON_ONCE(&dev_priv->drm,
116 			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
117 
118 	val = scale(val, panel->backlight.min, panel->backlight.max,
119 		    panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
120 
121 	return intel_backlight_invert_pwm_level(connector, val);
122 }
123 
124 u32 intel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
125 {
126 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
127 	struct intel_panel *panel = &connector->panel;
128 
129 	drm_WARN_ON_ONCE(&dev_priv->drm,
130 			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
131 
132 	if (dev_priv->params.invert_brightness > 0 ||
133 	    (dev_priv->params.invert_brightness == 0 && intel_has_quirk(dev_priv, QUIRK_INVERT_BRIGHTNESS)))
134 		val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
135 
136 	return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
137 		     panel->backlight.min, panel->backlight.max);
138 }
139 
140 static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
141 {
142 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
143 
144 	return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
145 }
146 
147 static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
148 {
149 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
150 
151 	return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
152 }
153 
154 static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
155 {
156 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
157 	struct intel_panel *panel = &connector->panel;
158 	u32 val;
159 
160 	val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
161 	if (DISPLAY_VER(dev_priv) < 4)
162 		val >>= 1;
163 
164 	if (panel->backlight.combination_mode) {
165 		u8 lbpc;
166 
167 		pci_read_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, &lbpc);
168 		val *= lbpc;
169 	}
170 
171 	return val;
172 }
173 
174 static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
175 {
176 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
177 
178 	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
179 		return 0;
180 
181 	return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
182 }
183 
184 static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
185 {
186 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
187 	struct intel_panel *panel = &connector->panel;
188 
189 	return intel_de_read(dev_priv,
190 			     BXT_BLC_PWM_DUTY(panel->backlight.controller));
191 }
192 
193 static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
194 {
195 	struct intel_panel *panel = &connector->panel;
196 	struct pwm_state state;
197 
198 	pwm_get_state(panel->backlight.pwm, &state);
199 	return pwm_get_relative_duty_cycle(&state, 100);
200 }
201 
202 static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
203 {
204 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
205 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
206 
207 	u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
208 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
209 }
210 
211 static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
212 {
213 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
214 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
215 	u32 tmp;
216 
217 	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
218 	intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
219 }
220 
221 static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
222 {
223 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
224 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
225 	struct intel_panel *panel = &connector->panel;
226 	u32 tmp, mask;
227 
228 	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
229 
230 	if (panel->backlight.combination_mode) {
231 		u8 lbpc;
232 
233 		lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
234 		level /= lbpc;
235 		pci_write_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, lbpc);
236 	}
237 
238 	if (DISPLAY_VER(dev_priv) == 4) {
239 		mask = BACKLIGHT_DUTY_CYCLE_MASK;
240 	} else {
241 		level <<= 1;
242 		mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
243 	}
244 
245 	tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
246 	intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
247 }
248 
249 static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
250 {
251 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
252 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
253 	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
254 	u32 tmp;
255 
256 	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
257 	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
258 }
259 
260 static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
261 {
262 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
263 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
264 	struct intel_panel *panel = &connector->panel;
265 
266 	intel_de_write(dev_priv,
267 		       BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
268 }
269 
270 static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
271 {
272 	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
273 
274 	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
275 	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
276 }
277 
278 static void
279 intel_panel_actually_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 drm_i915_private *i915 = to_i915(connector->base.dev);
283 	struct intel_panel *panel = &connector->panel;
284 
285 	drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
286 
287 	panel->backlight.funcs->set(conn_state, level);
288 }
289 
290 /* set backlight brightness to level in range [0..max], assuming hw min is
291  * respected.
292  */
293 void intel_backlight_set_acpi(const struct drm_connector_state *conn_state,
294 			      u32 user_level, u32 user_max)
295 {
296 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
297 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
298 	struct intel_panel *panel = &connector->panel;
299 	u32 hw_level;
300 
301 	/*
302 	 * Lack of crtc may occur during driver init because
303 	 * connection_mutex isn't held across the entire backlight
304 	 * setup + modeset readout, and the BIOS can issue the
305 	 * requests at any time.
306 	 */
307 	if (!panel->backlight.present || !conn_state->crtc)
308 		return;
309 
310 	mutex_lock(&dev_priv->display.backlight.lock);
311 
312 	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
313 
314 	hw_level = clamp_user_to_hw(connector, user_level, user_max);
315 	panel->backlight.level = hw_level;
316 
317 	if (panel->backlight.device)
318 		panel->backlight.device->props.brightness =
319 			scale_hw_to_user(connector,
320 					 panel->backlight.level,
321 					 panel->backlight.device->props.max_brightness);
322 
323 	if (panel->backlight.enabled)
324 		intel_panel_actually_set_backlight(conn_state, hw_level);
325 
326 	mutex_unlock(&dev_priv->display.backlight.lock);
327 }
328 
329 static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
330 {
331 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
332 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
333 	u32 tmp;
334 
335 	intel_backlight_set_pwm_level(old_conn_state, level);
336 
337 	/*
338 	 * Although we don't support or enable CPU PWM with LPT/SPT based
339 	 * systems, it may have been enabled prior to loading the
340 	 * driver. Disable to avoid warnings on LCPLL disable.
341 	 *
342 	 * This needs rework if we need to add support for CPU PWM on PCH split
343 	 * platforms.
344 	 */
345 	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
346 	if (tmp & BLM_PWM_ENABLE) {
347 		drm_dbg_kms(&dev_priv->drm,
348 			    "cpu backlight was enabled, disabling\n");
349 		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
350 			       tmp & ~BLM_PWM_ENABLE);
351 	}
352 
353 	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
354 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
355 }
356 
357 static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
358 {
359 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
360 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
361 	u32 tmp;
362 
363 	intel_backlight_set_pwm_level(old_conn_state, val);
364 
365 	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
366 	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
367 
368 	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
369 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
370 }
371 
372 static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
373 {
374 	intel_backlight_set_pwm_level(old_conn_state, val);
375 }
376 
377 static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
378 {
379 	struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
380 	u32 tmp;
381 
382 	intel_backlight_set_pwm_level(old_conn_state, val);
383 
384 	tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
385 	intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
386 }
387 
388 static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
389 {
390 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
391 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
392 	enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
393 	u32 tmp;
394 
395 	intel_backlight_set_pwm_level(old_conn_state, val);
396 
397 	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
398 	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
399 		       tmp & ~BLM_PWM_ENABLE);
400 }
401 
402 static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
403 {
404 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
405 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
406 	struct intel_panel *panel = &connector->panel;
407 	u32 tmp;
408 
409 	intel_backlight_set_pwm_level(old_conn_state, val);
410 
411 	tmp = intel_de_read(dev_priv,
412 			    BXT_BLC_PWM_CTL(panel->backlight.controller));
413 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
414 		       tmp & ~BXT_BLC_PWM_ENABLE);
415 
416 	if (panel->backlight.controller == 1) {
417 		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
418 		val &= ~UTIL_PIN_ENABLE;
419 		intel_de_write(dev_priv, UTIL_PIN_CTL, val);
420 	}
421 }
422 
423 static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
424 {
425 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
426 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
427 	struct intel_panel *panel = &connector->panel;
428 	u32 tmp;
429 
430 	intel_backlight_set_pwm_level(old_conn_state, val);
431 
432 	tmp = intel_de_read(dev_priv,
433 			    BXT_BLC_PWM_CTL(panel->backlight.controller));
434 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
435 		       tmp & ~BXT_BLC_PWM_ENABLE);
436 }
437 
438 static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
439 {
440 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
441 	struct intel_panel *panel = &connector->panel;
442 
443 	intel_backlight_set_pwm_level(old_conn_state, level);
444 
445 	panel->backlight.pwm_state.enabled = false;
446 	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
447 }
448 
449 void intel_backlight_disable(const struct drm_connector_state *old_conn_state)
450 {
451 	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
452 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
453 	struct intel_panel *panel = &connector->panel;
454 
455 	if (!panel->backlight.present)
456 		return;
457 
458 	/*
459 	 * Do not disable backlight on the vga_switcheroo path. When switching
460 	 * away from i915, the other client may depend on i915 to handle the
461 	 * backlight. This will leave the backlight on unnecessarily when
462 	 * another client is not activated.
463 	 */
464 	if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
465 		drm_dbg_kms(&dev_priv->drm,
466 			    "Skipping backlight disable on vga switch\n");
467 		return;
468 	}
469 
470 	mutex_lock(&dev_priv->display.backlight.lock);
471 
472 	if (panel->backlight.device)
473 		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
474 	panel->backlight.enabled = false;
475 	panel->backlight.funcs->disable(old_conn_state, 0);
476 
477 	mutex_unlock(&dev_priv->display.backlight.lock);
478 }
479 
480 static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
481 				 const struct drm_connector_state *conn_state, u32 level)
482 {
483 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
484 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
485 	struct intel_panel *panel = &connector->panel;
486 	u32 pch_ctl1, pch_ctl2, schicken;
487 
488 	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
489 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
490 		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
491 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
492 		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
493 	}
494 
495 	if (HAS_PCH_LPT(dev_priv)) {
496 		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
497 		if (panel->backlight.alternate_pwm_increment)
498 			schicken |= LPT_PWM_GRANULARITY;
499 		else
500 			schicken &= ~LPT_PWM_GRANULARITY;
501 		intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
502 	} else {
503 		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
504 		if (panel->backlight.alternate_pwm_increment)
505 			schicken |= SPT_PWM_GRANULARITY;
506 		else
507 			schicken &= ~SPT_PWM_GRANULARITY;
508 		intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
509 	}
510 
511 	pch_ctl2 = panel->backlight.pwm_level_max << 16;
512 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
513 
514 	pch_ctl1 = 0;
515 	if (panel->backlight.active_low_pwm)
516 		pch_ctl1 |= BLM_PCH_POLARITY;
517 
518 	/* After LPT, override is the default. */
519 	if (HAS_PCH_LPT(dev_priv))
520 		pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
521 
522 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
523 	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
524 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
525 		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
526 
527 	/* This won't stick until the above enable. */
528 	intel_backlight_set_pwm_level(conn_state, level);
529 }
530 
531 static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
532 				 const struct drm_connector_state *conn_state, u32 level)
533 {
534 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
535 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
536 	struct intel_panel *panel = &connector->panel;
537 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
538 	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
539 
540 	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
541 	if (cpu_ctl2 & BLM_PWM_ENABLE) {
542 		drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
543 		cpu_ctl2 &= ~BLM_PWM_ENABLE;
544 		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
545 	}
546 
547 	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
548 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
549 		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
550 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
551 		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
552 	}
553 
554 	if (cpu_transcoder == TRANSCODER_EDP)
555 		cpu_ctl2 = BLM_TRANSCODER_EDP;
556 	else
557 		cpu_ctl2 = BLM_PIPE(cpu_transcoder);
558 	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
559 	intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
560 	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
561 
562 	/* This won't stick until the above enable. */
563 	intel_backlight_set_pwm_level(conn_state, level);
564 
565 	pch_ctl2 = panel->backlight.pwm_level_max << 16;
566 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
567 
568 	pch_ctl1 = 0;
569 	if (panel->backlight.active_low_pwm)
570 		pch_ctl1 |= BLM_PCH_POLARITY;
571 
572 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
573 	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
574 	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
575 		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
576 }
577 
578 static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
579 				  const struct drm_connector_state *conn_state, u32 level)
580 {
581 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
582 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
583 	struct intel_panel *panel = &connector->panel;
584 	u32 ctl, freq;
585 
586 	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
587 	if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
588 		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
589 		intel_de_write(dev_priv, BLC_PWM_CTL, 0);
590 	}
591 
592 	freq = panel->backlight.pwm_level_max;
593 	if (panel->backlight.combination_mode)
594 		freq /= 0xff;
595 
596 	ctl = freq << 17;
597 	if (panel->backlight.combination_mode)
598 		ctl |= BLM_LEGACY_MODE;
599 	if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
600 		ctl |= BLM_POLARITY_PNV;
601 
602 	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
603 	intel_de_posting_read(dev_priv, BLC_PWM_CTL);
604 
605 	/* XXX: combine this into above write? */
606 	intel_backlight_set_pwm_level(conn_state, level);
607 
608 	/*
609 	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
610 	 * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
611 	 * that has backlight.
612 	 */
613 	if (DISPLAY_VER(dev_priv) == 2)
614 		intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
615 }
616 
617 static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
618 				  const struct drm_connector_state *conn_state, u32 level)
619 {
620 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
621 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
622 	struct intel_panel *panel = &connector->panel;
623 	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
624 	u32 ctl, ctl2, freq;
625 
626 	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
627 	if (ctl2 & BLM_PWM_ENABLE) {
628 		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
629 		ctl2 &= ~BLM_PWM_ENABLE;
630 		intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
631 	}
632 
633 	freq = panel->backlight.pwm_level_max;
634 	if (panel->backlight.combination_mode)
635 		freq /= 0xff;
636 
637 	ctl = freq << 16;
638 	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
639 
640 	ctl2 = BLM_PIPE(pipe);
641 	if (panel->backlight.combination_mode)
642 		ctl2 |= BLM_COMBINATION_MODE;
643 	if (panel->backlight.active_low_pwm)
644 		ctl2 |= BLM_POLARITY_I965;
645 	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
646 	intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
647 	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
648 
649 	intel_backlight_set_pwm_level(conn_state, level);
650 }
651 
652 static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
653 				 const struct drm_connector_state *conn_state, u32 level)
654 {
655 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
656 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
657 	struct intel_panel *panel = &connector->panel;
658 	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
659 	u32 ctl, ctl2;
660 
661 	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
662 	if (ctl2 & BLM_PWM_ENABLE) {
663 		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
664 		ctl2 &= ~BLM_PWM_ENABLE;
665 		intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
666 	}
667 
668 	ctl = panel->backlight.pwm_level_max << 16;
669 	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
670 
671 	/* XXX: combine this into above write? */
672 	intel_backlight_set_pwm_level(conn_state, level);
673 
674 	ctl2 = 0;
675 	if (panel->backlight.active_low_pwm)
676 		ctl2 |= BLM_POLARITY_I965;
677 	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
678 	intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
679 	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
680 		       ctl2 | BLM_PWM_ENABLE);
681 }
682 
683 static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
684 				 const struct drm_connector_state *conn_state, u32 level)
685 {
686 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
687 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
688 	struct intel_panel *panel = &connector->panel;
689 	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
690 	u32 pwm_ctl, val;
691 
692 	/* Controller 1 uses the utility pin. */
693 	if (panel->backlight.controller == 1) {
694 		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
695 		if (val & UTIL_PIN_ENABLE) {
696 			drm_dbg_kms(&dev_priv->drm,
697 				    "util pin already enabled\n");
698 			val &= ~UTIL_PIN_ENABLE;
699 			intel_de_write(dev_priv, UTIL_PIN_CTL, val);
700 		}
701 
702 		val = 0;
703 		if (panel->backlight.util_pin_active_low)
704 			val |= UTIL_PIN_POLARITY;
705 		intel_de_write(dev_priv, UTIL_PIN_CTL,
706 			       val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
707 	}
708 
709 	pwm_ctl = intel_de_read(dev_priv,
710 				BXT_BLC_PWM_CTL(panel->backlight.controller));
711 	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
712 		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
713 		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
714 		intel_de_write(dev_priv,
715 			       BXT_BLC_PWM_CTL(panel->backlight.controller),
716 			       pwm_ctl);
717 	}
718 
719 	intel_de_write(dev_priv,
720 		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
721 		       panel->backlight.pwm_level_max);
722 
723 	intel_backlight_set_pwm_level(conn_state, level);
724 
725 	pwm_ctl = 0;
726 	if (panel->backlight.active_low_pwm)
727 		pwm_ctl |= BXT_BLC_PWM_POLARITY;
728 
729 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
730 		       pwm_ctl);
731 	intel_de_posting_read(dev_priv,
732 			      BXT_BLC_PWM_CTL(panel->backlight.controller));
733 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
734 		       pwm_ctl | BXT_BLC_PWM_ENABLE);
735 }
736 
737 static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
738 				 const struct drm_connector_state *conn_state, u32 level)
739 {
740 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
741 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
742 	struct intel_panel *panel = &connector->panel;
743 	u32 pwm_ctl;
744 
745 	pwm_ctl = intel_de_read(dev_priv,
746 				BXT_BLC_PWM_CTL(panel->backlight.controller));
747 	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
748 		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
749 		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
750 		intel_de_write(dev_priv,
751 			       BXT_BLC_PWM_CTL(panel->backlight.controller),
752 			       pwm_ctl);
753 	}
754 
755 	intel_de_write(dev_priv,
756 		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
757 		       panel->backlight.pwm_level_max);
758 
759 	intel_backlight_set_pwm_level(conn_state, level);
760 
761 	pwm_ctl = 0;
762 	if (panel->backlight.active_low_pwm)
763 		pwm_ctl |= BXT_BLC_PWM_POLARITY;
764 
765 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
766 		       pwm_ctl);
767 	intel_de_posting_read(dev_priv,
768 			      BXT_BLC_PWM_CTL(panel->backlight.controller));
769 	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
770 		       pwm_ctl | BXT_BLC_PWM_ENABLE);
771 }
772 
773 static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
774 				     const struct drm_connector_state *conn_state, u32 level)
775 {
776 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
777 	struct intel_panel *panel = &connector->panel;
778 
779 	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
780 	panel->backlight.pwm_state.enabled = true;
781 	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
782 }
783 
784 static void __intel_backlight_enable(const struct intel_crtc_state *crtc_state,
785 				     const struct drm_connector_state *conn_state)
786 {
787 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
788 	struct intel_panel *panel = &connector->panel;
789 
790 	WARN_ON(panel->backlight.max == 0);
791 
792 	if (panel->backlight.level <= panel->backlight.min) {
793 		panel->backlight.level = panel->backlight.max;
794 		if (panel->backlight.device)
795 			panel->backlight.device->props.brightness =
796 				scale_hw_to_user(connector,
797 						 panel->backlight.level,
798 						 panel->backlight.device->props.max_brightness);
799 	}
800 
801 	panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
802 	panel->backlight.enabled = true;
803 	if (panel->backlight.device)
804 		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
805 }
806 
807 void intel_backlight_enable(const struct intel_crtc_state *crtc_state,
808 			    const struct drm_connector_state *conn_state)
809 {
810 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
811 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
812 	struct intel_panel *panel = &connector->panel;
813 	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
814 
815 	if (!panel->backlight.present)
816 		return;
817 
818 	drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
819 
820 	mutex_lock(&dev_priv->display.backlight.lock);
821 
822 	__intel_backlight_enable(crtc_state, conn_state);
823 
824 	mutex_unlock(&dev_priv->display.backlight.lock);
825 }
826 
827 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
828 static u32 intel_panel_get_backlight(struct intel_connector *connector)
829 {
830 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
831 	struct intel_panel *panel = &connector->panel;
832 	u32 val = 0;
833 
834 	mutex_lock(&dev_priv->display.backlight.lock);
835 
836 	if (panel->backlight.enabled)
837 		val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
838 
839 	mutex_unlock(&dev_priv->display.backlight.lock);
840 
841 	drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
842 	return val;
843 }
844 
845 /* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
846 static u32 scale_user_to_hw(struct intel_connector *connector,
847 			    u32 user_level, u32 user_max)
848 {
849 	struct intel_panel *panel = &connector->panel;
850 
851 	return scale(user_level, 0, user_max,
852 		     panel->backlight.min, panel->backlight.max);
853 }
854 
855 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
856 static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
857 				      u32 user_level, u32 user_max)
858 {
859 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
860 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
861 	struct intel_panel *panel = &connector->panel;
862 	u32 hw_level;
863 
864 	if (!panel->backlight.present)
865 		return;
866 
867 	mutex_lock(&dev_priv->display.backlight.lock);
868 
869 	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
870 
871 	hw_level = scale_user_to_hw(connector, user_level, user_max);
872 	panel->backlight.level = hw_level;
873 
874 	if (panel->backlight.enabled)
875 		intel_panel_actually_set_backlight(conn_state, hw_level);
876 
877 	mutex_unlock(&dev_priv->display.backlight.lock);
878 }
879 
880 static int intel_backlight_device_update_status(struct backlight_device *bd)
881 {
882 	struct intel_connector *connector = bl_get_data(bd);
883 	struct intel_panel *panel = &connector->panel;
884 	struct drm_device *dev = connector->base.dev;
885 
886 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
887 	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
888 		      bd->props.brightness, bd->props.max_brightness);
889 	intel_panel_set_backlight(connector->base.state, bd->props.brightness,
890 				  bd->props.max_brightness);
891 
892 	/*
893 	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
894 	 * backlight class device does not make it easy to differentiate
895 	 * between callbacks for brightness and bl_power, so our backlight_power
896 	 * callback needs to take this into account.
897 	 */
898 	if (panel->backlight.enabled) {
899 		if (panel->backlight.power) {
900 			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
901 				bd->props.brightness != 0;
902 			panel->backlight.power(connector, enable);
903 		}
904 	} else {
905 		bd->props.power = FB_BLANK_POWERDOWN;
906 	}
907 
908 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
909 	return 0;
910 }
911 
912 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
913 {
914 	struct intel_connector *connector = bl_get_data(bd);
915 	struct drm_device *dev = connector->base.dev;
916 	struct drm_i915_private *dev_priv = to_i915(dev);
917 	intel_wakeref_t wakeref;
918 	int ret = 0;
919 
920 	with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
921 		u32 hw_level;
922 
923 		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
924 
925 		hw_level = intel_panel_get_backlight(connector);
926 		ret = scale_hw_to_user(connector,
927 				       hw_level, bd->props.max_brightness);
928 
929 		drm_modeset_unlock(&dev->mode_config.connection_mutex);
930 	}
931 
932 	return ret;
933 }
934 
935 static const struct backlight_ops intel_backlight_device_ops = {
936 	.update_status = intel_backlight_device_update_status,
937 	.get_brightness = intel_backlight_device_get_brightness,
938 };
939 
940 int intel_backlight_device_register(struct intel_connector *connector)
941 {
942 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
943 	struct intel_panel *panel = &connector->panel;
944 	struct backlight_properties props;
945 	struct backlight_device *bd;
946 	const char *name;
947 	int ret = 0;
948 
949 	if (WARN_ON(panel->backlight.device))
950 		return -ENODEV;
951 
952 	if (!panel->backlight.present)
953 		return 0;
954 
955 	WARN_ON(panel->backlight.max == 0);
956 
957 	memset(&props, 0, sizeof(props));
958 	props.type = BACKLIGHT_RAW;
959 
960 	/*
961 	 * Note: Everything should work even if the backlight device max
962 	 * presented to the userspace is arbitrarily chosen.
963 	 */
964 	props.max_brightness = panel->backlight.max;
965 	props.brightness = scale_hw_to_user(connector,
966 					    panel->backlight.level,
967 					    props.max_brightness);
968 
969 	if (panel->backlight.enabled)
970 		props.power = FB_BLANK_UNBLANK;
971 	else
972 		props.power = FB_BLANK_POWERDOWN;
973 
974 	name = kstrdup("intel_backlight", GFP_KERNEL);
975 	if (!name)
976 		return -ENOMEM;
977 
978 	bd = backlight_device_get_by_name(name);
979 	if (bd) {
980 		put_device(&bd->dev);
981 		/*
982 		 * Using the same name independent of the drm device or connector
983 		 * prevents registration of multiple backlight devices in the
984 		 * driver. However, we need to use the default name for backward
985 		 * compatibility. Use unique names for subsequent backlight devices as a
986 		 * fallback when the default name already exists.
987 		 */
988 		kfree(name);
989 		name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
990 				 i915->drm.primary->index, connector->base.name);
991 		if (!name)
992 			return -ENOMEM;
993 	}
994 	bd = backlight_device_register(name, connector->base.kdev, connector,
995 				       &intel_backlight_device_ops, &props);
996 
997 	if (IS_ERR(bd)) {
998 		drm_err(&i915->drm,
999 			"[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
1000 			connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
1001 		ret = PTR_ERR(bd);
1002 		goto out;
1003 	}
1004 
1005 	panel->backlight.device = bd;
1006 
1007 	drm_dbg_kms(&i915->drm,
1008 		    "[CONNECTOR:%d:%s] backlight device %s registered\n",
1009 		    connector->base.base.id, connector->base.name, name);
1010 
1011 out:
1012 	kfree(name);
1013 
1014 	return ret;
1015 }
1016 
1017 void intel_backlight_device_unregister(struct intel_connector *connector)
1018 {
1019 	struct intel_panel *panel = &connector->panel;
1020 
1021 	if (panel->backlight.device) {
1022 		backlight_device_unregister(panel->backlight.device);
1023 		panel->backlight.device = NULL;
1024 	}
1025 }
1026 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1027 
1028 /*
1029  * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
1030  *      PWM increment = 1
1031  */
1032 static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1033 {
1034 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1035 
1036 	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
1037 				 pwm_freq_hz);
1038 }
1039 
1040 /*
1041  * BXT: PWM clock frequency = 19.2 MHz.
1042  */
1043 static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1044 {
1045 	return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
1046 }
1047 
1048 /*
1049  * SPT: This value represents the period of the PWM stream in clock periods
1050  * multiplied by 16 (default increment) or 128 (alternate increment selected in
1051  * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
1052  */
1053 static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1054 {
1055 	struct intel_panel *panel = &connector->panel;
1056 	u32 mul;
1057 
1058 	if (panel->backlight.alternate_pwm_increment)
1059 		mul = 128;
1060 	else
1061 		mul = 16;
1062 
1063 	return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
1064 }
1065 
1066 /*
1067  * LPT: This value represents the period of the PWM stream in clock periods
1068  * multiplied by 128 (default increment) or 16 (alternate increment, selected in
1069  * LPT SOUTH_CHICKEN2 register bit 5).
1070  */
1071 static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1072 {
1073 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1074 	struct intel_panel *panel = &connector->panel;
1075 	u32 mul, clock;
1076 
1077 	if (panel->backlight.alternate_pwm_increment)
1078 		mul = 16;
1079 	else
1080 		mul = 128;
1081 
1082 	if (HAS_PCH_LPT_H(dev_priv))
1083 		clock = MHz(135); /* LPT:H */
1084 	else
1085 		clock = MHz(24); /* LPT:LP */
1086 
1087 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1088 }
1089 
1090 /*
1091  * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
1092  * display raw clocks multiplied by 128.
1093  */
1094 static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1095 {
1096 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1097 
1098 	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
1099 				 pwm_freq_hz * 128);
1100 }
1101 
1102 /*
1103  * Gen2: This field determines the number of time base events (display core
1104  * clock frequency/32) in total for a complete cycle of modulated backlight
1105  * control.
1106  *
1107  * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
1108  * divided by 32.
1109  */
1110 static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1111 {
1112 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1113 	int clock;
1114 
1115 	if (IS_PINEVIEW(dev_priv))
1116 		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1117 	else
1118 		clock = KHz(dev_priv->display.cdclk.hw.cdclk);
1119 
1120 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
1121 }
1122 
1123 /*
1124  * Gen4: This value represents the period of the PWM stream in display core
1125  * clocks ([DevCTG] HRAW clocks) multiplied by 128.
1126  *
1127  */
1128 static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1129 {
1130 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1131 	int clock;
1132 
1133 	if (IS_G4X(dev_priv))
1134 		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1135 	else
1136 		clock = KHz(dev_priv->display.cdclk.hw.cdclk);
1137 
1138 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
1139 }
1140 
1141 /*
1142  * VLV: This value represents the period of the PWM stream in display core
1143  * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
1144  * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
1145  */
1146 static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1147 {
1148 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1149 	int mul, clock;
1150 
1151 	if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
1152 		if (IS_CHERRYVIEW(dev_priv))
1153 			clock = KHz(19200);
1154 		else
1155 			clock = MHz(25);
1156 		mul = 16;
1157 	} else {
1158 		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1159 		mul = 128;
1160 	}
1161 
1162 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1163 }
1164 
1165 static u16 get_vbt_pwm_freq(struct intel_connector *connector)
1166 {
1167 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1168 	u16 pwm_freq_hz = connector->panel.vbt.backlight.pwm_freq_hz;
1169 
1170 	if (pwm_freq_hz) {
1171 		drm_dbg_kms(&dev_priv->drm,
1172 			    "VBT defined backlight frequency %u Hz\n",
1173 			    pwm_freq_hz);
1174 	} else {
1175 		pwm_freq_hz = 200;
1176 		drm_dbg_kms(&dev_priv->drm,
1177 			    "default backlight frequency %u Hz\n",
1178 			    pwm_freq_hz);
1179 	}
1180 
1181 	return pwm_freq_hz;
1182 }
1183 
1184 static u32 get_backlight_max_vbt(struct intel_connector *connector)
1185 {
1186 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1187 	struct intel_panel *panel = &connector->panel;
1188 	u16 pwm_freq_hz = get_vbt_pwm_freq(connector);
1189 	u32 pwm;
1190 
1191 	if (!panel->backlight.pwm_funcs->hz_to_pwm) {
1192 		drm_dbg_kms(&dev_priv->drm,
1193 			    "backlight frequency conversion not supported\n");
1194 		return 0;
1195 	}
1196 
1197 	pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
1198 	if (!pwm) {
1199 		drm_dbg_kms(&dev_priv->drm,
1200 			    "backlight frequency conversion failed\n");
1201 		return 0;
1202 	}
1203 
1204 	return pwm;
1205 }
1206 
1207 /*
1208  * Note: The setup hooks can't assume pipe is set!
1209  */
1210 static u32 get_backlight_min_vbt(struct intel_connector *connector)
1211 {
1212 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1213 	struct intel_panel *panel = &connector->panel;
1214 	int min;
1215 
1216 	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
1217 
1218 	/*
1219 	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
1220 	 * to problems. There are such machines out there. Either our
1221 	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1222 	 * against this by letting the minimum be at most (arbitrarily chosen)
1223 	 * 25% of the max.
1224 	 */
1225 	min = clamp_t(int, connector->panel.vbt.backlight.min_brightness, 0, 64);
1226 	if (min != connector->panel.vbt.backlight.min_brightness) {
1227 		drm_dbg_kms(&dev_priv->drm,
1228 			    "clamping VBT min backlight %d/255 to %d/255\n",
1229 			    connector->panel.vbt.backlight.min_brightness, min);
1230 	}
1231 
1232 	/* vbt value is a coefficient in range [0..255] */
1233 	return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
1234 }
1235 
1236 static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
1237 {
1238 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1239 	struct intel_panel *panel = &connector->panel;
1240 	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1241 	bool alt, cpu_mode;
1242 
1243 	if (HAS_PCH_LPT(dev_priv))
1244 		alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
1245 	else
1246 		alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
1247 	panel->backlight.alternate_pwm_increment = alt;
1248 
1249 	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
1250 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1251 
1252 	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
1253 	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
1254 
1255 	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
1256 
1257 	if (!panel->backlight.pwm_level_max)
1258 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1259 
1260 	if (!panel->backlight.pwm_level_max)
1261 		return -ENODEV;
1262 
1263 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1264 
1265 	panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
1266 
1267 	cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
1268 		   !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
1269 		   (cpu_ctl2 & BLM_PWM_ENABLE);
1270 
1271 	if (cpu_mode) {
1272 		val = pch_get_backlight(connector, unused);
1273 
1274 		drm_dbg_kms(&dev_priv->drm,
1275 			    "CPU backlight register was enabled, switching to PCH override\n");
1276 
1277 		/* Write converted CPU PWM value to PCH override register */
1278 		lpt_set_backlight(connector->base.state, val);
1279 		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
1280 			       pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
1281 
1282 		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
1283 			       cpu_ctl2 & ~BLM_PWM_ENABLE);
1284 	}
1285 
1286 	return 0;
1287 }
1288 
1289 static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
1290 {
1291 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1292 	struct intel_panel *panel = &connector->panel;
1293 	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
1294 
1295 	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
1296 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1297 
1298 	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
1299 	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
1300 
1301 	if (!panel->backlight.pwm_level_max)
1302 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1303 
1304 	if (!panel->backlight.pwm_level_max)
1305 		return -ENODEV;
1306 
1307 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1308 
1309 	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
1310 	panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1311 		(pch_ctl1 & BLM_PCH_PWM_ENABLE);
1312 
1313 	return 0;
1314 }
1315 
1316 static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
1317 {
1318 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1319 	struct intel_panel *panel = &connector->panel;
1320 	u32 ctl, val;
1321 
1322 	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
1323 
1324 	if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
1325 		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1326 
1327 	if (IS_PINEVIEW(dev_priv))
1328 		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1329 
1330 	panel->backlight.pwm_level_max = ctl >> 17;
1331 
1332 	if (!panel->backlight.pwm_level_max) {
1333 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1334 		panel->backlight.pwm_level_max >>= 1;
1335 	}
1336 
1337 	if (!panel->backlight.pwm_level_max)
1338 		return -ENODEV;
1339 
1340 	if (panel->backlight.combination_mode)
1341 		panel->backlight.pwm_level_max *= 0xff;
1342 
1343 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1344 
1345 	val = i9xx_get_backlight(connector, unused);
1346 	val = intel_backlight_invert_pwm_level(connector, val);
1347 	val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
1348 
1349 	panel->backlight.pwm_enabled = val != 0;
1350 
1351 	return 0;
1352 }
1353 
1354 static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
1355 {
1356 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1357 	struct intel_panel *panel = &connector->panel;
1358 	u32 ctl, ctl2;
1359 
1360 	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
1361 	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1362 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1363 
1364 	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
1365 	panel->backlight.pwm_level_max = ctl >> 16;
1366 
1367 	if (!panel->backlight.pwm_level_max)
1368 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1369 
1370 	if (!panel->backlight.pwm_level_max)
1371 		return -ENODEV;
1372 
1373 	if (panel->backlight.combination_mode)
1374 		panel->backlight.pwm_level_max *= 0xff;
1375 
1376 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1377 
1378 	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
1379 
1380 	return 0;
1381 }
1382 
1383 static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1384 {
1385 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1386 	struct intel_panel *panel = &connector->panel;
1387 	u32 ctl, ctl2;
1388 
1389 	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
1390 		return -ENODEV;
1391 
1392 	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
1393 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1394 
1395 	ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
1396 	panel->backlight.pwm_level_max = ctl >> 16;
1397 
1398 	if (!panel->backlight.pwm_level_max)
1399 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1400 
1401 	if (!panel->backlight.pwm_level_max)
1402 		return -ENODEV;
1403 
1404 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1405 
1406 	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
1407 
1408 	return 0;
1409 }
1410 
1411 static int
1412 bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
1413 {
1414 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1415 	struct intel_panel *panel = &connector->panel;
1416 	u32 pwm_ctl, val;
1417 
1418 	panel->backlight.controller = connector->panel.vbt.backlight.controller;
1419 
1420 	pwm_ctl = intel_de_read(dev_priv,
1421 				BXT_BLC_PWM_CTL(panel->backlight.controller));
1422 
1423 	/* Controller 1 uses the utility pin. */
1424 	if (panel->backlight.controller == 1) {
1425 		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
1426 		panel->backlight.util_pin_active_low =
1427 					val & UTIL_PIN_POLARITY;
1428 	}
1429 
1430 	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1431 	panel->backlight.pwm_level_max =
1432 		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
1433 
1434 	if (!panel->backlight.pwm_level_max)
1435 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1436 
1437 	if (!panel->backlight.pwm_level_max)
1438 		return -ENODEV;
1439 
1440 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1441 
1442 	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
1443 
1444 	return 0;
1445 }
1446 
1447 static int
1448 cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
1449 {
1450 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1451 	struct intel_panel *panel = &connector->panel;
1452 	u32 pwm_ctl;
1453 
1454 	/*
1455 	 * CNP has the BXT implementation of backlight, but with only one
1456 	 * controller. TODO: ICP has multiple controllers but we only use
1457 	 * controller 0 for now.
1458 	 */
1459 	panel->backlight.controller = 0;
1460 
1461 	pwm_ctl = intel_de_read(dev_priv,
1462 				BXT_BLC_PWM_CTL(panel->backlight.controller));
1463 
1464 	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1465 	panel->backlight.pwm_level_max =
1466 		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
1467 
1468 	if (!panel->backlight.pwm_level_max)
1469 		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1470 
1471 	if (!panel->backlight.pwm_level_max)
1472 		return -ENODEV;
1473 
1474 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1475 
1476 	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
1477 
1478 	return 0;
1479 }
1480 
1481 static int ext_pwm_setup_backlight(struct intel_connector *connector,
1482 				   enum pipe pipe)
1483 {
1484 	struct drm_device *dev = connector->base.dev;
1485 	struct drm_i915_private *dev_priv = to_i915(dev);
1486 	struct intel_panel *panel = &connector->panel;
1487 	const char *desc;
1488 	u32 level;
1489 
1490 	/* Get the right PWM chip for DSI backlight according to VBT */
1491 	if (connector->panel.vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
1492 		panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
1493 		desc = "PMIC";
1494 	} else {
1495 		panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
1496 		desc = "SoC";
1497 	}
1498 
1499 	if (IS_ERR(panel->backlight.pwm)) {
1500 		drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
1501 			desc);
1502 		panel->backlight.pwm = NULL;
1503 		return -ENODEV;
1504 	}
1505 
1506 	panel->backlight.pwm_level_max = 100; /* 100% */
1507 	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1508 
1509 	if (pwm_is_enabled(panel->backlight.pwm)) {
1510 		/* PWM is already enabled, use existing settings */
1511 		pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
1512 
1513 		level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
1514 						    100);
1515 		level = intel_backlight_invert_pwm_level(connector, level);
1516 		panel->backlight.pwm_enabled = true;
1517 
1518 		drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
1519 			    NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
1520 			    get_vbt_pwm_freq(connector), level);
1521 	} else {
1522 		/* Set period from VBT frequency, leave other settings at 0. */
1523 		panel->backlight.pwm_state.period =
1524 			NSEC_PER_SEC / get_vbt_pwm_freq(connector);
1525 	}
1526 
1527 	drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
1528 		 desc);
1529 	return 0;
1530 }
1531 
1532 static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
1533 {
1534 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
1535 	struct intel_panel *panel = &connector->panel;
1536 
1537 	panel->backlight.pwm_funcs->set(conn_state,
1538 					intel_backlight_invert_pwm_level(connector, level));
1539 }
1540 
1541 static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
1542 {
1543 	struct intel_panel *panel = &connector->panel;
1544 
1545 	return intel_backlight_invert_pwm_level(connector,
1546 					    panel->backlight.pwm_funcs->get(connector, pipe));
1547 }
1548 
1549 static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
1550 				       const struct drm_connector_state *conn_state, u32 level)
1551 {
1552 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
1553 	struct intel_panel *panel = &connector->panel;
1554 
1555 	panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
1556 					   intel_backlight_invert_pwm_level(connector, level));
1557 }
1558 
1559 static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
1560 {
1561 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
1562 	struct intel_panel *panel = &connector->panel;
1563 
1564 	panel->backlight.pwm_funcs->disable(conn_state,
1565 					    intel_backlight_invert_pwm_level(connector, level));
1566 }
1567 
1568 static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1569 {
1570 	struct intel_panel *panel = &connector->panel;
1571 	int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
1572 
1573 	if (ret < 0)
1574 		return ret;
1575 
1576 	panel->backlight.min = panel->backlight.pwm_level_min;
1577 	panel->backlight.max = panel->backlight.pwm_level_max;
1578 	panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
1579 	panel->backlight.enabled = panel->backlight.pwm_enabled;
1580 
1581 	return 0;
1582 }
1583 
1584 void intel_backlight_update(struct intel_atomic_state *state,
1585 			    struct intel_encoder *encoder,
1586 			    const struct intel_crtc_state *crtc_state,
1587 			    const struct drm_connector_state *conn_state)
1588 {
1589 	struct intel_connector *connector = to_intel_connector(conn_state->connector);
1590 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1591 	struct intel_panel *panel = &connector->panel;
1592 
1593 	if (!panel->backlight.present)
1594 		return;
1595 
1596 	mutex_lock(&dev_priv->display.backlight.lock);
1597 	if (!panel->backlight.enabled)
1598 		__intel_backlight_enable(crtc_state, conn_state);
1599 
1600 	mutex_unlock(&dev_priv->display.backlight.lock);
1601 }
1602 
1603 int intel_backlight_setup(struct intel_connector *connector, enum pipe pipe)
1604 {
1605 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1606 	struct intel_panel *panel = &connector->panel;
1607 	int ret;
1608 
1609 	if (!connector->panel.vbt.backlight.present) {
1610 		if (intel_has_quirk(dev_priv, QUIRK_BACKLIGHT_PRESENT)) {
1611 			drm_dbg_kms(&dev_priv->drm,
1612 				    "no backlight present per VBT, but present per quirk\n");
1613 		} else {
1614 			drm_dbg_kms(&dev_priv->drm,
1615 				    "no backlight present per VBT\n");
1616 			return 0;
1617 		}
1618 	}
1619 
1620 	/* ensure intel_panel has been initialized first */
1621 	if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
1622 		return -ENODEV;
1623 
1624 	/* set level and max in panel struct */
1625 	mutex_lock(&dev_priv->display.backlight.lock);
1626 	ret = panel->backlight.funcs->setup(connector, pipe);
1627 	mutex_unlock(&dev_priv->display.backlight.lock);
1628 
1629 	if (ret) {
1630 		drm_dbg_kms(&dev_priv->drm,
1631 			    "failed to setup backlight for connector %s\n",
1632 			    connector->base.name);
1633 		return ret;
1634 	}
1635 
1636 	panel->backlight.present = true;
1637 
1638 	drm_dbg_kms(&dev_priv->drm,
1639 		    "Connector %s backlight initialized, %s, brightness %u/%u\n",
1640 		    connector->base.name,
1641 		    str_enabled_disabled(panel->backlight.enabled),
1642 		    panel->backlight.level, panel->backlight.max);
1643 
1644 	return 0;
1645 }
1646 
1647 void intel_backlight_destroy(struct intel_panel *panel)
1648 {
1649 	/* dispose of the pwm */
1650 	if (panel->backlight.pwm)
1651 		pwm_put(panel->backlight.pwm);
1652 
1653 	panel->backlight.present = false;
1654 }
1655 
1656 static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
1657 	.setup = bxt_setup_backlight,
1658 	.enable = bxt_enable_backlight,
1659 	.disable = bxt_disable_backlight,
1660 	.set = bxt_set_backlight,
1661 	.get = bxt_get_backlight,
1662 	.hz_to_pwm = bxt_hz_to_pwm,
1663 };
1664 
1665 static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
1666 	.setup = cnp_setup_backlight,
1667 	.enable = cnp_enable_backlight,
1668 	.disable = cnp_disable_backlight,
1669 	.set = bxt_set_backlight,
1670 	.get = bxt_get_backlight,
1671 	.hz_to_pwm = cnp_hz_to_pwm,
1672 };
1673 
1674 static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
1675 	.setup = lpt_setup_backlight,
1676 	.enable = lpt_enable_backlight,
1677 	.disable = lpt_disable_backlight,
1678 	.set = lpt_set_backlight,
1679 	.get = lpt_get_backlight,
1680 	.hz_to_pwm = lpt_hz_to_pwm,
1681 };
1682 
1683 static const struct intel_panel_bl_funcs spt_pwm_funcs = {
1684 	.setup = lpt_setup_backlight,
1685 	.enable = lpt_enable_backlight,
1686 	.disable = lpt_disable_backlight,
1687 	.set = lpt_set_backlight,
1688 	.get = lpt_get_backlight,
1689 	.hz_to_pwm = spt_hz_to_pwm,
1690 };
1691 
1692 static const struct intel_panel_bl_funcs pch_pwm_funcs = {
1693 	.setup = pch_setup_backlight,
1694 	.enable = pch_enable_backlight,
1695 	.disable = pch_disable_backlight,
1696 	.set = pch_set_backlight,
1697 	.get = pch_get_backlight,
1698 	.hz_to_pwm = pch_hz_to_pwm,
1699 };
1700 
1701 static const struct intel_panel_bl_funcs ext_pwm_funcs = {
1702 	.setup = ext_pwm_setup_backlight,
1703 	.enable = ext_pwm_enable_backlight,
1704 	.disable = ext_pwm_disable_backlight,
1705 	.set = ext_pwm_set_backlight,
1706 	.get = ext_pwm_get_backlight,
1707 };
1708 
1709 static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
1710 	.setup = vlv_setup_backlight,
1711 	.enable = vlv_enable_backlight,
1712 	.disable = vlv_disable_backlight,
1713 	.set = vlv_set_backlight,
1714 	.get = vlv_get_backlight,
1715 	.hz_to_pwm = vlv_hz_to_pwm,
1716 };
1717 
1718 static const struct intel_panel_bl_funcs i965_pwm_funcs = {
1719 	.setup = i965_setup_backlight,
1720 	.enable = i965_enable_backlight,
1721 	.disable = i965_disable_backlight,
1722 	.set = i9xx_set_backlight,
1723 	.get = i9xx_get_backlight,
1724 	.hz_to_pwm = i965_hz_to_pwm,
1725 };
1726 
1727 static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
1728 	.setup = i9xx_setup_backlight,
1729 	.enable = i9xx_enable_backlight,
1730 	.disable = i9xx_disable_backlight,
1731 	.set = i9xx_set_backlight,
1732 	.get = i9xx_get_backlight,
1733 	.hz_to_pwm = i9xx_hz_to_pwm,
1734 };
1735 
1736 static const struct intel_panel_bl_funcs pwm_bl_funcs = {
1737 	.setup = intel_pwm_setup_backlight,
1738 	.enable = intel_pwm_enable_backlight,
1739 	.disable = intel_pwm_disable_backlight,
1740 	.set = intel_pwm_set_backlight,
1741 	.get = intel_pwm_get_backlight,
1742 };
1743 
1744 /* Set up chip specific backlight functions */
1745 void intel_backlight_init_funcs(struct intel_panel *panel)
1746 {
1747 	struct intel_connector *connector =
1748 		container_of(panel, struct intel_connector, panel);
1749 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1750 
1751 	if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
1752 	    intel_dsi_dcs_init_backlight_funcs(connector) == 0)
1753 		return;
1754 
1755 	if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
1756 		panel->backlight.pwm_funcs = &bxt_pwm_funcs;
1757 	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
1758 		panel->backlight.pwm_funcs = &cnp_pwm_funcs;
1759 	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
1760 		if (HAS_PCH_LPT(dev_priv))
1761 			panel->backlight.pwm_funcs = &lpt_pwm_funcs;
1762 		else
1763 			panel->backlight.pwm_funcs = &spt_pwm_funcs;
1764 	} else if (HAS_PCH_SPLIT(dev_priv)) {
1765 		panel->backlight.pwm_funcs = &pch_pwm_funcs;
1766 	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
1767 		if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
1768 			panel->backlight.pwm_funcs = &ext_pwm_funcs;
1769 		} else {
1770 			panel->backlight.pwm_funcs = &vlv_pwm_funcs;
1771 		}
1772 	} else if (DISPLAY_VER(dev_priv) == 4) {
1773 		panel->backlight.pwm_funcs = &i965_pwm_funcs;
1774 	} else {
1775 		panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
1776 	}
1777 
1778 	if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP) {
1779 		if (intel_dp_aux_init_backlight_funcs(connector) == 0)
1780 			return;
1781 
1782 		if (!intel_has_quirk(dev_priv, QUIRK_NO_PPS_BACKLIGHT_POWER_HOOK))
1783 			connector->panel.backlight.power = intel_pps_backlight_power;
1784 	}
1785 
1786 	/* We're using a standard PWM backlight interface */
1787 	panel->backlight.funcs = &pwm_bl_funcs;
1788 }
1789