xref: /dflybsd-src/sys/dev/drm/i915/intel_panel.c (revision 2c64e990ea2bb1213bd0758af732469466873ba6)
1 /*
2  * Copyright © 2006-2010 Intel Corporation
3  * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  *
24  * Authors:
25  *	Eric Anholt <eric@anholt.net>
26  *      Dave Airlie <airlied@linux.ie>
27  *      Jesse Barnes <jesse.barnes@intel.com>
28  *      Chris Wilson <chris@chris-wilson.co.uk>
29  */
30 
31 #include <linux/kernel.h>
32 #include <linux/moduleparam.h>
33 #include "intel_drv.h"
34 
35 void
36 intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
37 		       struct drm_display_mode *adjusted_mode)
38 {
39 	drm_mode_copy(adjusted_mode, fixed_mode);
40 
41 	drm_mode_set_crtcinfo(adjusted_mode, 0);
42 }
43 
44 /**
45  * intel_find_panel_downclock - find the reduced downclock for LVDS in EDID
46  * @dev: drm device
47  * @fixed_mode : panel native mode
48  * @connector: LVDS/eDP connector
49  *
50  * Return downclock_avail
51  * Find the reduced downclock for LVDS/eDP in EDID.
52  */
53 struct drm_display_mode *
54 intel_find_panel_downclock(struct drm_device *dev,
55 			struct drm_display_mode *fixed_mode,
56 			struct drm_connector *connector)
57 {
58 	struct drm_display_mode *scan, *tmp_mode;
59 	int temp_downclock;
60 
61 	temp_downclock = fixed_mode->clock;
62 	tmp_mode = NULL;
63 
64 	list_for_each_entry(scan, &connector->probed_modes, head) {
65 		/*
66 		 * If one mode has the same resolution with the fixed_panel
67 		 * mode while they have the different refresh rate, it means
68 		 * that the reduced downclock is found. In such
69 		 * case we can set the different FPx0/1 to dynamically select
70 		 * between low and high frequency.
71 		 */
72 		if (scan->hdisplay == fixed_mode->hdisplay &&
73 		    scan->hsync_start == fixed_mode->hsync_start &&
74 		    scan->hsync_end == fixed_mode->hsync_end &&
75 		    scan->htotal == fixed_mode->htotal &&
76 		    scan->vdisplay == fixed_mode->vdisplay &&
77 		    scan->vsync_start == fixed_mode->vsync_start &&
78 		    scan->vsync_end == fixed_mode->vsync_end &&
79 		    scan->vtotal == fixed_mode->vtotal) {
80 			if (scan->clock < temp_downclock) {
81 				/*
82 				 * The downclock is already found. But we
83 				 * expect to find the lower downclock.
84 				 */
85 				temp_downclock = scan->clock;
86 				tmp_mode = scan;
87 			}
88 		}
89 	}
90 
91 	if (temp_downclock < fixed_mode->clock)
92 		return drm_mode_duplicate(dev, tmp_mode);
93 	else
94 		return NULL;
95 }
96 
97 /* adjusted_mode has been preset to be the panel's fixed mode */
98 void
99 intel_pch_panel_fitting(struct intel_crtc *intel_crtc,
100 			struct intel_crtc_state *pipe_config,
101 			int fitting_mode)
102 {
103 	struct drm_display_mode *adjusted_mode;
104 	int x, y, width, height;
105 
106 	adjusted_mode = &pipe_config->base.adjusted_mode;
107 
108 	x = y = width = height = 0;
109 
110 	/* Native modes don't need fitting */
111 	if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
112 	    adjusted_mode->vdisplay == pipe_config->pipe_src_h)
113 		goto done;
114 
115 	switch (fitting_mode) {
116 	case DRM_MODE_SCALE_CENTER:
117 		width = pipe_config->pipe_src_w;
118 		height = pipe_config->pipe_src_h;
119 		x = (adjusted_mode->hdisplay - width + 1)/2;
120 		y = (adjusted_mode->vdisplay - height + 1)/2;
121 		break;
122 
123 	case DRM_MODE_SCALE_ASPECT:
124 		/* Scale but preserve the aspect ratio */
125 		{
126 			u32 scaled_width = adjusted_mode->hdisplay
127 				* pipe_config->pipe_src_h;
128 			u32 scaled_height = pipe_config->pipe_src_w
129 				* adjusted_mode->vdisplay;
130 			if (scaled_width > scaled_height) { /* pillar */
131 				width = scaled_height / pipe_config->pipe_src_h;
132 				if (width & 1)
133 					width++;
134 				x = (adjusted_mode->hdisplay - width + 1) / 2;
135 				y = 0;
136 				height = adjusted_mode->vdisplay;
137 			} else if (scaled_width < scaled_height) { /* letter */
138 				height = scaled_width / pipe_config->pipe_src_w;
139 				if (height & 1)
140 				    height++;
141 				y = (adjusted_mode->vdisplay - height + 1) / 2;
142 				x = 0;
143 				width = adjusted_mode->hdisplay;
144 			} else {
145 				x = y = 0;
146 				width = adjusted_mode->hdisplay;
147 				height = adjusted_mode->vdisplay;
148 			}
149 		}
150 		break;
151 
152 	case DRM_MODE_SCALE_FULLSCREEN:
153 		x = y = 0;
154 		width = adjusted_mode->hdisplay;
155 		height = adjusted_mode->vdisplay;
156 		break;
157 
158 	default:
159 		WARN(1, "bad panel fit mode: %d\n", fitting_mode);
160 		return;
161 	}
162 
163 done:
164 	pipe_config->pch_pfit.pos = (x << 16) | y;
165 	pipe_config->pch_pfit.size = (width << 16) | height;
166 	pipe_config->pch_pfit.enabled = pipe_config->pch_pfit.size != 0;
167 }
168 
169 static void
170 centre_horizontally(struct drm_display_mode *mode,
171 		    int width)
172 {
173 	u32 border, sync_pos, blank_width, sync_width;
174 
175 	/* keep the hsync and hblank widths constant */
176 	sync_width = mode->crtc_hsync_end - mode->crtc_hsync_start;
177 	blank_width = mode->crtc_hblank_end - mode->crtc_hblank_start;
178 	sync_pos = (blank_width - sync_width + 1) / 2;
179 
180 	border = (mode->hdisplay - width + 1) / 2;
181 	border += border & 1; /* make the border even */
182 
183 	mode->crtc_hdisplay = width;
184 	mode->crtc_hblank_start = width + border;
185 	mode->crtc_hblank_end = mode->crtc_hblank_start + blank_width;
186 
187 	mode->crtc_hsync_start = mode->crtc_hblank_start + sync_pos;
188 	mode->crtc_hsync_end = mode->crtc_hsync_start + sync_width;
189 }
190 
191 static void
192 centre_vertically(struct drm_display_mode *mode,
193 		  int height)
194 {
195 	u32 border, sync_pos, blank_width, sync_width;
196 
197 	/* keep the vsync and vblank widths constant */
198 	sync_width = mode->crtc_vsync_end - mode->crtc_vsync_start;
199 	blank_width = mode->crtc_vblank_end - mode->crtc_vblank_start;
200 	sync_pos = (blank_width - sync_width + 1) / 2;
201 
202 	border = (mode->vdisplay - height + 1) / 2;
203 
204 	mode->crtc_vdisplay = height;
205 	mode->crtc_vblank_start = height + border;
206 	mode->crtc_vblank_end = mode->crtc_vblank_start + blank_width;
207 
208 	mode->crtc_vsync_start = mode->crtc_vblank_start + sync_pos;
209 	mode->crtc_vsync_end = mode->crtc_vsync_start + sync_width;
210 }
211 
212 static inline u32 panel_fitter_scaling(u32 source, u32 target)
213 {
214 	/*
215 	 * Floating point operation is not supported. So the FACTOR
216 	 * is defined, which can avoid the floating point computation
217 	 * when calculating the panel ratio.
218 	 */
219 #define ACCURACY 12
220 #define FACTOR (1 << ACCURACY)
221 	u32 ratio = source * FACTOR / target;
222 	return (FACTOR * ratio + FACTOR/2) / FACTOR;
223 }
224 
225 static void i965_scale_aspect(struct intel_crtc_state *pipe_config,
226 			      u32 *pfit_control)
227 {
228 	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
229 	u32 scaled_width = adjusted_mode->hdisplay *
230 		pipe_config->pipe_src_h;
231 	u32 scaled_height = pipe_config->pipe_src_w *
232 		adjusted_mode->vdisplay;
233 
234 	/* 965+ is easy, it does everything in hw */
235 	if (scaled_width > scaled_height)
236 		*pfit_control |= PFIT_ENABLE |
237 			PFIT_SCALING_PILLAR;
238 	else if (scaled_width < scaled_height)
239 		*pfit_control |= PFIT_ENABLE |
240 			PFIT_SCALING_LETTER;
241 	else if (adjusted_mode->hdisplay != pipe_config->pipe_src_w)
242 		*pfit_control |= PFIT_ENABLE | PFIT_SCALING_AUTO;
243 }
244 
245 static void i9xx_scale_aspect(struct intel_crtc_state *pipe_config,
246 			      u32 *pfit_control, u32 *pfit_pgm_ratios,
247 			      u32 *border)
248 {
249 	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
250 	u32 scaled_width = adjusted_mode->hdisplay *
251 		pipe_config->pipe_src_h;
252 	u32 scaled_height = pipe_config->pipe_src_w *
253 		adjusted_mode->vdisplay;
254 	u32 bits;
255 
256 	/*
257 	 * For earlier chips we have to calculate the scaling
258 	 * ratio by hand and program it into the
259 	 * PFIT_PGM_RATIO register
260 	 */
261 	if (scaled_width > scaled_height) { /* pillar */
262 		centre_horizontally(adjusted_mode,
263 				    scaled_height /
264 				    pipe_config->pipe_src_h);
265 
266 		*border = LVDS_BORDER_ENABLE;
267 		if (pipe_config->pipe_src_h != adjusted_mode->vdisplay) {
268 			bits = panel_fitter_scaling(pipe_config->pipe_src_h,
269 						    adjusted_mode->vdisplay);
270 
271 			*pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
272 					     bits << PFIT_VERT_SCALE_SHIFT);
273 			*pfit_control |= (PFIT_ENABLE |
274 					  VERT_INTERP_BILINEAR |
275 					  HORIZ_INTERP_BILINEAR);
276 		}
277 	} else if (scaled_width < scaled_height) { /* letter */
278 		centre_vertically(adjusted_mode,
279 				  scaled_width /
280 				  pipe_config->pipe_src_w);
281 
282 		*border = LVDS_BORDER_ENABLE;
283 		if (pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
284 			bits = panel_fitter_scaling(pipe_config->pipe_src_w,
285 						    adjusted_mode->hdisplay);
286 
287 			*pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
288 					     bits << PFIT_VERT_SCALE_SHIFT);
289 			*pfit_control |= (PFIT_ENABLE |
290 					  VERT_INTERP_BILINEAR |
291 					  HORIZ_INTERP_BILINEAR);
292 		}
293 	} else {
294 		/* Aspects match, Let hw scale both directions */
295 		*pfit_control |= (PFIT_ENABLE |
296 				  VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |
297 				  VERT_INTERP_BILINEAR |
298 				  HORIZ_INTERP_BILINEAR);
299 	}
300 }
301 
302 void intel_gmch_panel_fitting(struct intel_crtc *intel_crtc,
303 			      struct intel_crtc_state *pipe_config,
304 			      int fitting_mode)
305 {
306 	struct drm_device *dev = intel_crtc->base.dev;
307 	u32 pfit_control = 0, pfit_pgm_ratios = 0, border = 0;
308 	struct drm_display_mode *adjusted_mode;
309 
310 	adjusted_mode = &pipe_config->base.adjusted_mode;
311 
312 	/* Native modes don't need fitting */
313 	if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
314 	    adjusted_mode->vdisplay == pipe_config->pipe_src_h)
315 		goto out;
316 
317 	switch (fitting_mode) {
318 	case DRM_MODE_SCALE_CENTER:
319 		/*
320 		 * For centered modes, we have to calculate border widths &
321 		 * heights and modify the values programmed into the CRTC.
322 		 */
323 		centre_horizontally(adjusted_mode, pipe_config->pipe_src_w);
324 		centre_vertically(adjusted_mode, pipe_config->pipe_src_h);
325 		border = LVDS_BORDER_ENABLE;
326 		break;
327 	case DRM_MODE_SCALE_ASPECT:
328 		/* Scale but preserve the aspect ratio */
329 		if (INTEL_INFO(dev)->gen >= 4)
330 			i965_scale_aspect(pipe_config, &pfit_control);
331 		else
332 			i9xx_scale_aspect(pipe_config, &pfit_control,
333 					  &pfit_pgm_ratios, &border);
334 		break;
335 	case DRM_MODE_SCALE_FULLSCREEN:
336 		/*
337 		 * Full scaling, even if it changes the aspect ratio.
338 		 * Fortunately this is all done for us in hw.
339 		 */
340 		if (pipe_config->pipe_src_h != adjusted_mode->vdisplay ||
341 		    pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
342 			pfit_control |= PFIT_ENABLE;
343 			if (INTEL_INFO(dev)->gen >= 4)
344 				pfit_control |= PFIT_SCALING_AUTO;
345 			else
346 				pfit_control |= (VERT_AUTO_SCALE |
347 						 VERT_INTERP_BILINEAR |
348 						 HORIZ_AUTO_SCALE |
349 						 HORIZ_INTERP_BILINEAR);
350 		}
351 		break;
352 	default:
353 		WARN(1, "bad panel fit mode: %d\n", fitting_mode);
354 		return;
355 	}
356 
357 	/* 965+ wants fuzzy fitting */
358 	/* FIXME: handle multiple panels by failing gracefully */
359 	if (INTEL_INFO(dev)->gen >= 4)
360 		pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
361 				 PFIT_FILTER_FUZZY);
362 
363 out:
364 	if ((pfit_control & PFIT_ENABLE) == 0) {
365 		pfit_control = 0;
366 		pfit_pgm_ratios = 0;
367 	}
368 
369 	/* Make sure pre-965 set dither correctly for 18bpp panels. */
370 	if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
371 		pfit_control |= PANEL_8TO6_DITHER_ENABLE;
372 
373 	pipe_config->gmch_pfit.control = pfit_control;
374 	pipe_config->gmch_pfit.pgm_ratios = pfit_pgm_ratios;
375 	pipe_config->gmch_pfit.lvds_border_bits = border;
376 }
377 
378 enum drm_connector_status
379 intel_panel_detect(struct drm_device *dev)
380 {
381 	struct drm_i915_private *dev_priv = dev->dev_private;
382 
383 	/* Assume that the BIOS does not lie through the OpRegion... */
384 	if (!i915.panel_ignore_lid && dev_priv->opregion.lid_state) {
385 		return ioread32(dev_priv->opregion.lid_state) & 0x1 ?
386 			connector_status_connected :
387 			connector_status_disconnected;
388 	}
389 
390 	switch (i915.panel_ignore_lid) {
391 	case -2:
392 		return connector_status_connected;
393 	case -1:
394 		return connector_status_disconnected;
395 	default:
396 		return connector_status_unknown;
397 	}
398 }
399 
400 /**
401  * scale - scale values from one range to another
402  *
403  * @source_val: value in range [@source_min..@source_max]
404  *
405  * Return @source_val in range [@source_min..@source_max] scaled to range
406  * [@target_min..@target_max].
407  */
408 static uint32_t scale(uint32_t source_val,
409 		      uint32_t source_min, uint32_t source_max,
410 		      uint32_t target_min, uint32_t target_max)
411 {
412 	uint64_t target_val;
413 
414 	WARN_ON(source_min > source_max);
415 	WARN_ON(target_min > target_max);
416 
417 	/* defensive */
418 	source_val = clamp(source_val, source_min, source_max);
419 
420 	/* avoid overflows */
421 	target_val = DIV_ROUND_CLOSEST_ULL((uint64_t)(source_val - source_min) *
422 			(target_max - target_min), source_max - source_min);
423 	target_val += target_min;
424 
425 	return target_val;
426 }
427 
428 /* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
429 static inline u32 scale_user_to_hw(struct intel_connector *connector,
430 				   u32 user_level, u32 user_max)
431 {
432 	struct intel_panel *panel = &connector->panel;
433 
434 	return scale(user_level, 0, user_max,
435 		     panel->backlight.min, panel->backlight.max);
436 }
437 
438 /* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
439  * to [hw_min..hw_max]. */
440 static inline u32 clamp_user_to_hw(struct intel_connector *connector,
441 				   u32 user_level, u32 user_max)
442 {
443 	struct intel_panel *panel = &connector->panel;
444 	u32 hw_level;
445 
446 	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
447 	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
448 
449 	return hw_level;
450 }
451 
452 /* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
453 static inline u32 scale_hw_to_user(struct intel_connector *connector,
454 				   u32 hw_level, u32 user_max)
455 {
456 	struct intel_panel *panel = &connector->panel;
457 
458 	return scale(hw_level, panel->backlight.min, panel->backlight.max,
459 		     0, user_max);
460 }
461 
462 static u32 intel_panel_compute_brightness(struct intel_connector *connector,
463 					  u32 val)
464 {
465 	struct drm_device *dev = connector->base.dev;
466 	struct drm_i915_private *dev_priv = dev->dev_private;
467 	struct intel_panel *panel = &connector->panel;
468 
469 	WARN_ON(panel->backlight.max == 0);
470 
471 	if (i915.invert_brightness < 0)
472 		return val;
473 
474 	if (i915.invert_brightness > 0 ||
475 	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
476 		return panel->backlight.max - val;
477 	}
478 
479 	return val;
480 }
481 
482 static u32 bdw_get_backlight(struct intel_connector *connector)
483 {
484 	struct drm_device *dev = connector->base.dev;
485 	struct drm_i915_private *dev_priv = dev->dev_private;
486 
487 	return I915_READ(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
488 }
489 
490 static u32 pch_get_backlight(struct intel_connector *connector)
491 {
492 	struct drm_device *dev = connector->base.dev;
493 	struct drm_i915_private *dev_priv = dev->dev_private;
494 
495 	return I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
496 }
497 
498 static u32 i9xx_get_backlight(struct intel_connector *connector)
499 {
500 	struct drm_device *dev = connector->base.dev;
501 	struct drm_i915_private *dev_priv = dev->dev_private;
502 	struct intel_panel *panel = &connector->panel;
503 	u32 val;
504 
505 	val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
506 	if (INTEL_INFO(dev)->gen < 4)
507 		val >>= 1;
508 
509 	if (panel->backlight.combination_mode) {
510 		u8 lbpc;
511 
512 		pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
513 		val *= lbpc;
514 	}
515 
516 	return val;
517 }
518 
519 static u32 _vlv_get_backlight(struct drm_device *dev, enum i915_pipe pipe)
520 {
521 	struct drm_i915_private *dev_priv = dev->dev_private;
522 
523 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
524 		return 0;
525 
526 	return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
527 }
528 
529 static u32 vlv_get_backlight(struct intel_connector *connector)
530 {
531 	struct drm_device *dev = connector->base.dev;
532 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
533 
534 	return _vlv_get_backlight(dev, pipe);
535 }
536 
537 #if 0
538 static u32 intel_panel_get_backlight(struct intel_connector *connector)
539 {
540 	struct drm_device *dev = connector->base.dev;
541 	struct drm_i915_private *dev_priv = dev->dev_private;
542 	struct intel_panel *panel = &connector->panel;
543 	u32 val = 0;
544 
545 	mutex_lock(&dev_priv->backlight_lock);
546 
547 	if (panel->backlight.enabled) {
548 		val = dev_priv->display.get_backlight(connector);
549 		val = intel_panel_compute_brightness(connector, val);
550 	}
551 
552 	mutex_unlock(&dev_priv->backlight_lock);
553 
554 	DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
555 	return val;
556 }
557 #endif
558 
559 static void bdw_set_backlight(struct intel_connector *connector, u32 level)
560 {
561 	struct drm_device *dev = connector->base.dev;
562 	struct drm_i915_private *dev_priv = dev->dev_private;
563 	u32 val = I915_READ(BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
564 	I915_WRITE(BLC_PWM_PCH_CTL2, val | level);
565 }
566 
567 static void pch_set_backlight(struct intel_connector *connector, u32 level)
568 {
569 	struct drm_device *dev = connector->base.dev;
570 	struct drm_i915_private *dev_priv = dev->dev_private;
571 	u32 tmp;
572 
573 	tmp = I915_READ(BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
574 	I915_WRITE(BLC_PWM_CPU_CTL, tmp | level);
575 }
576 
577 static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
578 {
579 	struct drm_device *dev = connector->base.dev;
580 	struct drm_i915_private *dev_priv = dev->dev_private;
581 	struct intel_panel *panel = &connector->panel;
582 	u32 tmp, mask;
583 
584 	WARN_ON(panel->backlight.max == 0);
585 
586 	if (panel->backlight.combination_mode) {
587 		u8 lbpc;
588 
589 		lbpc = level * 0xfe / panel->backlight.max + 1;
590 		level /= lbpc;
591 		pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc);
592 	}
593 
594 	if (IS_GEN4(dev)) {
595 		mask = BACKLIGHT_DUTY_CYCLE_MASK;
596 	} else {
597 		level <<= 1;
598 		mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
599 	}
600 
601 	tmp = I915_READ(BLC_PWM_CTL) & ~mask;
602 	I915_WRITE(BLC_PWM_CTL, tmp | level);
603 }
604 
605 static void vlv_set_backlight(struct intel_connector *connector, u32 level)
606 {
607 	struct drm_device *dev = connector->base.dev;
608 	struct drm_i915_private *dev_priv = dev->dev_private;
609 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
610 	u32 tmp;
611 
612 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
613 		return;
614 
615 	tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
616 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
617 }
618 
619 static void
620 intel_panel_actually_set_backlight(struct intel_connector *connector, u32 level)
621 {
622 	struct drm_device *dev = connector->base.dev;
623 	struct drm_i915_private *dev_priv = dev->dev_private;
624 
625 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
626 
627 	level = intel_panel_compute_brightness(connector, level);
628 	dev_priv->display.set_backlight(connector, level);
629 }
630 
631 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
632 static void intel_panel_set_backlight(struct intel_connector *connector,
633 				      u32 user_level, u32 user_max)
634 {
635 	struct drm_device *dev = connector->base.dev;
636 	struct drm_i915_private *dev_priv = dev->dev_private;
637 	struct intel_panel *panel = &connector->panel;
638 	u32 hw_level;
639 
640 	if (!panel->backlight.present)
641 		return;
642 
643 	mutex_lock(&dev_priv->backlight_lock);
644 
645 	WARN_ON(panel->backlight.max == 0);
646 
647 	hw_level = scale_user_to_hw(connector, user_level, user_max);
648 	panel->backlight.level = hw_level;
649 
650 	if (panel->backlight.enabled)
651 		intel_panel_actually_set_backlight(connector, hw_level);
652 
653 	mutex_unlock(&dev_priv->backlight_lock);
654 }
655 
656 /* set backlight brightness to level in range [0..max], assuming hw min is
657  * respected.
658  */
659 void intel_panel_set_backlight_acpi(struct intel_connector *connector,
660 				    u32 user_level, u32 user_max)
661 {
662 	struct drm_device *dev = connector->base.dev;
663 	struct drm_i915_private *dev_priv = dev->dev_private;
664 	struct intel_panel *panel = &connector->panel;
665 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
666 	u32 hw_level;
667 
668 	/*
669 	 * INVALID_PIPE may occur during driver init because
670 	 * connection_mutex isn't held across the entire backlight
671 	 * setup + modeset readout, and the BIOS can issue the
672 	 * requests at any time.
673 	 */
674 	if (!panel->backlight.present || pipe == INVALID_PIPE)
675 		return;
676 
677 	mutex_lock(&dev_priv->backlight_lock);
678 
679 	WARN_ON(panel->backlight.max == 0);
680 
681 	hw_level = clamp_user_to_hw(connector, user_level, user_max);
682 	panel->backlight.level = hw_level;
683 
684 	if (panel->backlight.device)
685 		panel->backlight.device->props.brightness =
686 			scale_hw_to_user(connector,
687 					 panel->backlight.level,
688 					 panel->backlight.device->props.max_brightness);
689 
690 	if (panel->backlight.enabled)
691 		intel_panel_actually_set_backlight(connector, hw_level);
692 
693 	mutex_unlock(&dev_priv->backlight_lock);
694 }
695 
696 static void pch_disable_backlight(struct intel_connector *connector)
697 {
698 	struct drm_device *dev = connector->base.dev;
699 	struct drm_i915_private *dev_priv = dev->dev_private;
700 	u32 tmp;
701 
702 	intel_panel_actually_set_backlight(connector, 0);
703 
704 	tmp = I915_READ(BLC_PWM_CPU_CTL2);
705 	I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
706 
707 	tmp = I915_READ(BLC_PWM_PCH_CTL1);
708 	I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
709 }
710 
711 static void i9xx_disable_backlight(struct intel_connector *connector)
712 {
713 	intel_panel_actually_set_backlight(connector, 0);
714 }
715 
716 static void i965_disable_backlight(struct intel_connector *connector)
717 {
718 	struct drm_device *dev = connector->base.dev;
719 	struct drm_i915_private *dev_priv = dev->dev_private;
720 	u32 tmp;
721 
722 	intel_panel_actually_set_backlight(connector, 0);
723 
724 	tmp = I915_READ(BLC_PWM_CTL2);
725 	I915_WRITE(BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
726 }
727 
728 static void vlv_disable_backlight(struct intel_connector *connector)
729 {
730 	struct drm_device *dev = connector->base.dev;
731 	struct drm_i915_private *dev_priv = dev->dev_private;
732 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
733 	u32 tmp;
734 
735 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
736 		return;
737 
738 	intel_panel_actually_set_backlight(connector, 0);
739 
740 	tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
741 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
742 }
743 
744 void intel_panel_disable_backlight(struct intel_connector *connector)
745 {
746 	struct drm_device *dev = connector->base.dev;
747 	struct drm_i915_private *dev_priv = dev->dev_private;
748 	struct intel_panel *panel = &connector->panel;
749 
750 	if (!panel->backlight.present)
751 		return;
752 
753 	/*
754 	 * Do not disable backlight on the vgaswitcheroo path. When switching
755 	 * away from i915, the other client may depend on i915 to handle the
756 	 * backlight. This will leave the backlight on unnecessarily when
757 	 * another client is not activated.
758 	 */
759 	if (dev->switch_power_state == DRM_SWITCH_POWER_CHANGING) {
760 		DRM_DEBUG_DRIVER("Skipping backlight disable on vga switch\n");
761 		return;
762 	}
763 
764 	mutex_lock(&dev_priv->backlight_lock);
765 
766 	if (panel->backlight.device)
767 		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
768 	panel->backlight.enabled = false;
769 	dev_priv->display.disable_backlight(connector);
770 
771 	mutex_unlock(&dev_priv->backlight_lock);
772 }
773 
774 static void bdw_enable_backlight(struct intel_connector *connector)
775 {
776 	struct drm_device *dev = connector->base.dev;
777 	struct drm_i915_private *dev_priv = dev->dev_private;
778 	struct intel_panel *panel = &connector->panel;
779 	u32 pch_ctl1, pch_ctl2;
780 
781 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
782 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
783 		DRM_DEBUG_KMS("pch backlight already enabled\n");
784 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
785 		I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
786 	}
787 
788 	pch_ctl2 = panel->backlight.max << 16;
789 	I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
790 
791 	pch_ctl1 = 0;
792 	if (panel->backlight.active_low_pwm)
793 		pch_ctl1 |= BLM_PCH_POLARITY;
794 
795 	/* After LPT, override is the default. */
796 	if (HAS_PCH_LPT(dev_priv))
797 		pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
798 
799 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
800 	POSTING_READ(BLC_PWM_PCH_CTL1);
801 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
802 
803 	/* This won't stick until the above enable. */
804 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
805 }
806 
807 static void pch_enable_backlight(struct intel_connector *connector)
808 {
809 	struct drm_device *dev = connector->base.dev;
810 	struct drm_i915_private *dev_priv = dev->dev_private;
811 	struct intel_panel *panel = &connector->panel;
812 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
813 	enum transcoder cpu_transcoder =
814 		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
815 	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
816 
817 	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
818 	if (cpu_ctl2 & BLM_PWM_ENABLE) {
819 		DRM_DEBUG_KMS("cpu backlight already enabled\n");
820 		cpu_ctl2 &= ~BLM_PWM_ENABLE;
821 		I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
822 	}
823 
824 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
825 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
826 		DRM_DEBUG_KMS("pch backlight already enabled\n");
827 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
828 		I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
829 	}
830 
831 	if (cpu_transcoder == TRANSCODER_EDP)
832 		cpu_ctl2 = BLM_TRANSCODER_EDP;
833 	else
834 		cpu_ctl2 = BLM_PIPE(cpu_transcoder);
835 	I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
836 	POSTING_READ(BLC_PWM_CPU_CTL2);
837 	I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
838 
839 	/* This won't stick until the above enable. */
840 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
841 
842 	pch_ctl2 = panel->backlight.max << 16;
843 	I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
844 
845 	pch_ctl1 = 0;
846 	if (panel->backlight.active_low_pwm)
847 		pch_ctl1 |= BLM_PCH_POLARITY;
848 
849 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
850 	POSTING_READ(BLC_PWM_PCH_CTL1);
851 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
852 }
853 
854 static void i9xx_enable_backlight(struct intel_connector *connector)
855 {
856 	struct drm_device *dev = connector->base.dev;
857 	struct drm_i915_private *dev_priv = dev->dev_private;
858 	struct intel_panel *panel = &connector->panel;
859 	u32 ctl, freq;
860 
861 	ctl = I915_READ(BLC_PWM_CTL);
862 	if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
863 		DRM_DEBUG_KMS("backlight already enabled\n");
864 		I915_WRITE(BLC_PWM_CTL, 0);
865 	}
866 
867 	freq = panel->backlight.max;
868 	if (panel->backlight.combination_mode)
869 		freq /= 0xff;
870 
871 	ctl = freq << 17;
872 	if (panel->backlight.combination_mode)
873 		ctl |= BLM_LEGACY_MODE;
874 	if (IS_PINEVIEW(dev) && panel->backlight.active_low_pwm)
875 		ctl |= BLM_POLARITY_PNV;
876 
877 	I915_WRITE(BLC_PWM_CTL, ctl);
878 	POSTING_READ(BLC_PWM_CTL);
879 
880 	/* XXX: combine this into above write? */
881 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
882 }
883 
884 static void i965_enable_backlight(struct intel_connector *connector)
885 {
886 	struct drm_device *dev = connector->base.dev;
887 	struct drm_i915_private *dev_priv = dev->dev_private;
888 	struct intel_panel *panel = &connector->panel;
889 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
890 	u32 ctl, ctl2, freq;
891 
892 	ctl2 = I915_READ(BLC_PWM_CTL2);
893 	if (ctl2 & BLM_PWM_ENABLE) {
894 		DRM_DEBUG_KMS("backlight already enabled\n");
895 		ctl2 &= ~BLM_PWM_ENABLE;
896 		I915_WRITE(BLC_PWM_CTL2, ctl2);
897 	}
898 
899 	freq = panel->backlight.max;
900 	if (panel->backlight.combination_mode)
901 		freq /= 0xff;
902 
903 	ctl = freq << 16;
904 	I915_WRITE(BLC_PWM_CTL, ctl);
905 
906 	ctl2 = BLM_PIPE(pipe);
907 	if (panel->backlight.combination_mode)
908 		ctl2 |= BLM_COMBINATION_MODE;
909 	if (panel->backlight.active_low_pwm)
910 		ctl2 |= BLM_POLARITY_I965;
911 	I915_WRITE(BLC_PWM_CTL2, ctl2);
912 	POSTING_READ(BLC_PWM_CTL2);
913 	I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
914 
915 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
916 }
917 
918 static void vlv_enable_backlight(struct intel_connector *connector)
919 {
920 	struct drm_device *dev = connector->base.dev;
921 	struct drm_i915_private *dev_priv = dev->dev_private;
922 	struct intel_panel *panel = &connector->panel;
923 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
924 	u32 ctl, ctl2;
925 
926 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
927 		return;
928 
929 	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
930 	if (ctl2 & BLM_PWM_ENABLE) {
931 		DRM_DEBUG_KMS("backlight already enabled\n");
932 		ctl2 &= ~BLM_PWM_ENABLE;
933 		I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
934 	}
935 
936 	ctl = panel->backlight.max << 16;
937 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
938 
939 	/* XXX: combine this into above write? */
940 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
941 
942 	ctl2 = 0;
943 	if (panel->backlight.active_low_pwm)
944 		ctl2 |= BLM_POLARITY_I965;
945 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
946 	POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
947 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
948 }
949 
950 void intel_panel_enable_backlight(struct intel_connector *connector)
951 {
952 	struct drm_device *dev = connector->base.dev;
953 	struct drm_i915_private *dev_priv = dev->dev_private;
954 	struct intel_panel *panel = &connector->panel;
955 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
956 
957 	if (!panel->backlight.present)
958 		return;
959 
960 	DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
961 
962 	mutex_lock(&dev_priv->backlight_lock);
963 
964 	WARN_ON(panel->backlight.max == 0);
965 
966 	if (panel->backlight.level <= panel->backlight.min) {
967 		panel->backlight.level = panel->backlight.max;
968 		if (panel->backlight.device)
969 			panel->backlight.device->props.brightness =
970 				scale_hw_to_user(connector,
971 						 panel->backlight.level,
972 						 panel->backlight.device->props.max_brightness);
973 	}
974 
975 	dev_priv->display.enable_backlight(connector);
976 	panel->backlight.enabled = true;
977 	if (panel->backlight.device)
978 		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
979 
980 	mutex_unlock(&dev_priv->backlight_lock);
981 }
982 
983 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
984 static int intel_backlight_device_update_status(struct backlight_device *bd)
985 {
986 #if 0
987 	struct intel_connector *connector = bl_get_data(bd);
988 	struct intel_panel *panel = &connector->panel;
989 	struct drm_device *dev = connector->base.dev;
990 
991 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
992 	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
993 		      bd->props.brightness, bd->props.max_brightness);
994 	intel_panel_set_backlight(connector, bd->props.brightness,
995 				  bd->props.max_brightness);
996 
997 	/*
998 	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
999 	 * backlight class device does not make it easy to to differentiate
1000 	 * between callbacks for brightness and bl_power, so our backlight_power
1001 	 * callback needs to take this into account.
1002 	 */
1003 	if (panel->backlight.enabled) {
1004 		if (panel->backlight_power) {
1005 			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
1006 				bd->props.brightness != 0;
1007 			panel->backlight_power(connector, enable);
1008 		}
1009 	} else {
1010 		bd->props.power = FB_BLANK_POWERDOWN;
1011 	}
1012 
1013 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1014 #endif
1015 	return 0;
1016 }
1017 
1018 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
1019 {
1020 #if 0
1021 	struct intel_connector *connector = bl_get_data(bd);
1022 	struct drm_device *dev = connector->base.dev;
1023 	struct drm_i915_private *dev_priv = dev->dev_private;
1024 	u32 hw_level;
1025 	int ret;
1026 
1027 	intel_runtime_pm_get(dev_priv);
1028 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1029 
1030 	hw_level = intel_panel_get_backlight(connector);
1031 	ret = scale_hw_to_user(connector, hw_level, bd->props.max_brightness);
1032 
1033 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1034 	intel_runtime_pm_put(dev_priv);
1035 
1036 	return ret;
1037 #endif
1038 	return 0;
1039 }
1040 
1041 static const struct backlight_ops intel_backlight_device_ops = {
1042 	.update_status = intel_backlight_device_update_status,
1043 	.get_brightness = intel_backlight_device_get_brightness,
1044 };
1045 
1046 static int intel_backlight_device_register(struct intel_connector *connector)
1047 {
1048 	struct intel_panel *panel = &connector->panel;
1049 	struct backlight_properties props;
1050 
1051 	if (WARN_ON(panel->backlight.device))
1052 		return -ENODEV;
1053 
1054 	if (!panel->backlight.present)
1055 		return 0;
1056 
1057 	WARN_ON(panel->backlight.max == 0);
1058 
1059 	memset(&props, 0, sizeof(props));
1060 	props.type = BACKLIGHT_RAW;
1061 
1062 	/*
1063 	 * Note: Everything should work even if the backlight device max
1064 	 * presented to the userspace is arbitrarily chosen.
1065 	 */
1066 	props.max_brightness = panel->backlight.max;
1067 	props.brightness = scale_hw_to_user(connector,
1068 					    panel->backlight.level,
1069 					    props.max_brightness);
1070 
1071 	if (panel->backlight.enabled)
1072 		props.power = FB_BLANK_UNBLANK;
1073 	else
1074 		props.power = FB_BLANK_POWERDOWN;
1075 
1076 	/*
1077 	 * Note: using the same name independent of the connector prevents
1078 	 * registration of multiple backlight devices in the driver.
1079 	 */
1080 #if 0
1081 	panel->backlight.device =
1082 		backlight_device_register("intel_backlight",
1083 					  connector->base.kdev,
1084 					  connector,
1085 					  &intel_backlight_device_ops, &props);
1086 
1087 	if (IS_ERR(panel->backlight.device)) {
1088 		DRM_ERROR("Failed to register backlight: %ld\n",
1089 			  PTR_ERR(panel->backlight.device));
1090 		panel->backlight.device = NULL;
1091 		return -ENODEV;
1092 	}
1093 #endif
1094 
1095 	DRM_DEBUG_KMS("Connector %s backlight sysfs interface registered\n",
1096 		      connector->base.name);
1097 
1098 	return 0;
1099 }
1100 
1101 static void intel_backlight_device_unregister(struct intel_connector *connector)
1102 {
1103 #if 0
1104 	struct intel_panel *panel = &connector->panel;
1105 
1106 	if (panel->backlight.device) {
1107 		backlight_device_unregister(panel->backlight.device);
1108 		panel->backlight.device = NULL;
1109 	}
1110 #endif
1111 }
1112 #else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1113 static int intel_backlight_device_register(struct intel_connector *connector)
1114 {
1115 	return 0;
1116 }
1117 static void intel_backlight_device_unregister(struct intel_connector *connector)
1118 {
1119 }
1120 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1121 
1122 /*
1123  * Note: The setup hooks can't assume pipe is set!
1124  *
1125  * XXX: Query mode clock or hardware clock and program PWM modulation frequency
1126  * appropriately when it's 0. Use VBT and/or sane defaults.
1127  */
1128 static u32 get_backlight_min_vbt(struct intel_connector *connector)
1129 {
1130 	struct drm_device *dev = connector->base.dev;
1131 	struct drm_i915_private *dev_priv = dev->dev_private;
1132 	struct intel_panel *panel = &connector->panel;
1133 	int min;
1134 
1135 	WARN_ON(panel->backlight.max == 0);
1136 
1137 	/*
1138 	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
1139 	 * to problems. There are such machines out there. Either our
1140 	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1141 	 * against this by letting the minimum be at most (arbitrarily chosen)
1142 	 * 25% of the max.
1143 	 */
1144 	min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
1145 	if (min != dev_priv->vbt.backlight.min_brightness) {
1146 		DRM_DEBUG_KMS("clamping VBT min backlight %d/255 to %d/255\n",
1147 			      dev_priv->vbt.backlight.min_brightness, min);
1148 	}
1149 
1150 	/* vbt value is a coefficient in range [0..255] */
1151 	return scale(min, 0, 255, 0, panel->backlight.max);
1152 }
1153 
1154 static int bdw_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1155 {
1156 	struct drm_device *dev = connector->base.dev;
1157 	struct drm_i915_private *dev_priv = dev->dev_private;
1158 	struct intel_panel *panel = &connector->panel;
1159 	u32 pch_ctl1, pch_ctl2, val;
1160 
1161 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1162 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1163 
1164 	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1165 	panel->backlight.max = pch_ctl2 >> 16;
1166 	if (!panel->backlight.max)
1167 		return -ENODEV;
1168 
1169 	panel->backlight.min = get_backlight_min_vbt(connector);
1170 
1171 	val = bdw_get_backlight(connector);
1172 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1173 
1174 	panel->backlight.enabled = (pch_ctl1 & BLM_PCH_PWM_ENABLE) &&
1175 		panel->backlight.level != 0;
1176 
1177 	return 0;
1178 }
1179 
1180 static int pch_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1181 {
1182 	struct drm_device *dev = connector->base.dev;
1183 	struct drm_i915_private *dev_priv = dev->dev_private;
1184 	struct intel_panel *panel = &connector->panel;
1185 	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1186 
1187 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1188 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1189 
1190 	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1191 	panel->backlight.max = pch_ctl2 >> 16;
1192 	if (!panel->backlight.max)
1193 		return -ENODEV;
1194 
1195 	panel->backlight.min = get_backlight_min_vbt(connector);
1196 
1197 	val = pch_get_backlight(connector);
1198 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1199 
1200 	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
1201 	panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1202 		(pch_ctl1 & BLM_PCH_PWM_ENABLE) && panel->backlight.level != 0;
1203 
1204 	return 0;
1205 }
1206 
1207 static int i9xx_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1208 {
1209 	struct drm_device *dev = connector->base.dev;
1210 	struct drm_i915_private *dev_priv = dev->dev_private;
1211 	struct intel_panel *panel = &connector->panel;
1212 	u32 ctl, val;
1213 
1214 	ctl = I915_READ(BLC_PWM_CTL);
1215 
1216 	if (IS_GEN2(dev) || IS_I915GM(dev) || IS_I945GM(dev))
1217 		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1218 
1219 	if (IS_PINEVIEW(dev))
1220 		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1221 
1222 	panel->backlight.max = ctl >> 17;
1223 	if (panel->backlight.combination_mode)
1224 		panel->backlight.max *= 0xff;
1225 
1226 	if (!panel->backlight.max)
1227 		return -ENODEV;
1228 
1229 	panel->backlight.min = get_backlight_min_vbt(connector);
1230 
1231 	val = i9xx_get_backlight(connector);
1232 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1233 
1234 	panel->backlight.enabled = panel->backlight.level != 0;
1235 
1236 	return 0;
1237 }
1238 
1239 static int i965_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1240 {
1241 	struct drm_device *dev = connector->base.dev;
1242 	struct drm_i915_private *dev_priv = dev->dev_private;
1243 	struct intel_panel *panel = &connector->panel;
1244 	u32 ctl, ctl2, val;
1245 
1246 	ctl2 = I915_READ(BLC_PWM_CTL2);
1247 	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1248 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1249 
1250 	ctl = I915_READ(BLC_PWM_CTL);
1251 	panel->backlight.max = ctl >> 16;
1252 	if (panel->backlight.combination_mode)
1253 		panel->backlight.max *= 0xff;
1254 
1255 	if (!panel->backlight.max)
1256 		return -ENODEV;
1257 
1258 	panel->backlight.min = get_backlight_min_vbt(connector);
1259 
1260 	val = i9xx_get_backlight(connector);
1261 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1262 
1263 	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1264 		panel->backlight.level != 0;
1265 
1266 	return 0;
1267 }
1268 
1269 static int vlv_setup_backlight(struct intel_connector *connector, enum i915_pipe pipe)
1270 {
1271 	struct drm_device *dev = connector->base.dev;
1272 	struct drm_i915_private *dev_priv = dev->dev_private;
1273 	struct intel_panel *panel = &connector->panel;
1274 	enum i915_pipe p;
1275 	u32 ctl, ctl2, val;
1276 
1277 	for_each_pipe(dev_priv, p) {
1278 		u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
1279 
1280 		/* Skip if the modulation freq is already set */
1281 		if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
1282 			continue;
1283 
1284 		cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
1285 		I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
1286 			   cur_val);
1287 	}
1288 
1289 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
1290 		return -ENODEV;
1291 
1292 	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
1293 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1294 
1295 	ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
1296 	panel->backlight.max = ctl >> 16;
1297 	if (!panel->backlight.max)
1298 		return -ENODEV;
1299 
1300 	panel->backlight.min = get_backlight_min_vbt(connector);
1301 
1302 	val = _vlv_get_backlight(dev, pipe);
1303 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1304 
1305 	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1306 		panel->backlight.level != 0;
1307 
1308 	return 0;
1309 }
1310 
1311 #ifdef __DragonFly__
1312 /*
1313  * Read max backlight level
1314  */
1315 static int
1316 sysctl_backlight_max(SYSCTL_HANDLER_ARGS)
1317 {
1318 	int err, val;
1319 	struct intel_connector *connector = arg1;
1320 	struct drm_device *dev = connector->base.dev;
1321 	struct drm_i915_private *dev_priv = dev->dev_private;
1322 	struct intel_panel *panel = &connector->panel;
1323 
1324 	mutex_lock(&dev_priv->backlight_lock);
1325 	val = panel->backlight.max;
1326 	mutex_unlock(&dev_priv->backlight_lock);
1327 
1328 	err = sysctl_handle_int(oidp, &val, 0, req);
1329 	return(err);
1330 }
1331 
1332 /*
1333  * Read/write backlight level
1334  */
1335 static int
1336 sysctl_backlight_handler(SYSCTL_HANDLER_ARGS)
1337 {
1338 	struct intel_connector *connector = arg1;
1339 	struct drm_device *dev = connector->base.dev;
1340 	struct drm_i915_private *dev_priv = dev->dev_private;
1341 	struct intel_panel *panel = &connector->panel;
1342 	int err, val;
1343 	u32 user_level, max_brightness;
1344 
1345 	mutex_lock(&dev_priv->backlight_lock);
1346 	max_brightness = panel->backlight.max;
1347 	user_level = scale_hw_to_user(connector, panel->backlight.level,
1348 	    max_brightness);
1349 	mutex_unlock(&dev_priv->backlight_lock);
1350 
1351 	val = user_level;
1352 	err = sysctl_handle_int(oidp, &val, 0, req);
1353 	if (err != 0 || req->newptr == NULL) {
1354 		return(err);
1355 	}
1356 
1357 	if (val != user_level && val >= 0 && val <= max_brightness) {
1358 		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1359 		intel_panel_set_backlight(arg1, val, max_brightness);
1360 		drm_modeset_unlock(&dev->mode_config.connection_mutex);
1361 	}
1362 
1363 	return(err);
1364 }
1365 #endif /* __DragonFly__ */
1366 
1367 int intel_panel_setup_backlight(struct drm_connector *connector, enum i915_pipe pipe)
1368 {
1369 	struct drm_device *dev = connector->dev;
1370 	struct drm_i915_private *dev_priv = dev->dev_private;
1371 	struct intel_connector *intel_connector = to_intel_connector(connector);
1372 	struct intel_panel *panel = &intel_connector->panel;
1373 	int ret;
1374 
1375 	if (!dev_priv->vbt.backlight.present) {
1376 		if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
1377 			DRM_DEBUG_KMS("no backlight present per VBT, but present per quirk\n");
1378 		} else {
1379 			DRM_DEBUG_KMS("no backlight present per VBT\n");
1380 			return 0;
1381 		}
1382 	}
1383 
1384 	/* set level and max in panel struct */
1385 	mutex_lock(&dev_priv->backlight_lock);
1386 	ret = dev_priv->display.setup_backlight(intel_connector, pipe);
1387 	mutex_unlock(&dev_priv->backlight_lock);
1388 
1389 	if (ret) {
1390 		DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
1391 			      connector->name);
1392 		return ret;
1393 	}
1394 
1395 	panel->backlight.present = true;
1396 
1397 #ifdef __DragonFly__
1398 	SYSCTL_ADD_PROC(&connector->dev->sysctl->ctx, &sysctl__hw_children,
1399 			OID_AUTO, "backlight_max",
1400 			CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_ANYBODY,
1401 			connector, sizeof(int),
1402 			sysctl_backlight_max,
1403 			"I", "Max backlight level");
1404 	SYSCTL_ADD_PROC(&connector->dev->sysctl->ctx, &sysctl__hw_children,
1405 			OID_AUTO, "backlight_level",
1406 			CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY,
1407 			connector, sizeof(int),
1408 			sysctl_backlight_handler,
1409 			"I", "Backlight level");
1410 #endif
1411 
1412 	DRM_DEBUG_KMS("Connector %s backlight initialized, %s, brightness %u/%u\n",
1413 		      connector->name,
1414 		      panel->backlight.enabled ? "enabled" : "disabled",
1415 		      panel->backlight.level, panel->backlight.max);
1416 
1417 	return 0;
1418 }
1419 
1420 void intel_panel_destroy_backlight(struct drm_connector *connector)
1421 {
1422 	struct intel_connector *intel_connector = to_intel_connector(connector);
1423 	struct intel_panel *panel = &intel_connector->panel;
1424 
1425 	panel->backlight.present = false;
1426 }
1427 
1428 /* Set up chip specific backlight functions */
1429 void intel_panel_init_backlight_funcs(struct drm_device *dev)
1430 {
1431 	struct drm_i915_private *dev_priv = dev->dev_private;
1432 
1433 	if (IS_BROADWELL(dev) || (INTEL_INFO(dev)->gen >= 9)) {
1434 		dev_priv->display.setup_backlight = bdw_setup_backlight;
1435 		dev_priv->display.enable_backlight = bdw_enable_backlight;
1436 		dev_priv->display.disable_backlight = pch_disable_backlight;
1437 		dev_priv->display.set_backlight = bdw_set_backlight;
1438 		dev_priv->display.get_backlight = bdw_get_backlight;
1439 	} else if (HAS_PCH_SPLIT(dev)) {
1440 		dev_priv->display.setup_backlight = pch_setup_backlight;
1441 		dev_priv->display.enable_backlight = pch_enable_backlight;
1442 		dev_priv->display.disable_backlight = pch_disable_backlight;
1443 		dev_priv->display.set_backlight = pch_set_backlight;
1444 		dev_priv->display.get_backlight = pch_get_backlight;
1445 	} else if (IS_VALLEYVIEW(dev)) {
1446 		dev_priv->display.setup_backlight = vlv_setup_backlight;
1447 		dev_priv->display.enable_backlight = vlv_enable_backlight;
1448 		dev_priv->display.disable_backlight = vlv_disable_backlight;
1449 		dev_priv->display.set_backlight = vlv_set_backlight;
1450 		dev_priv->display.get_backlight = vlv_get_backlight;
1451 	} else if (IS_GEN4(dev)) {
1452 		dev_priv->display.setup_backlight = i965_setup_backlight;
1453 		dev_priv->display.enable_backlight = i965_enable_backlight;
1454 		dev_priv->display.disable_backlight = i965_disable_backlight;
1455 		dev_priv->display.set_backlight = i9xx_set_backlight;
1456 		dev_priv->display.get_backlight = i9xx_get_backlight;
1457 	} else {
1458 		dev_priv->display.setup_backlight = i9xx_setup_backlight;
1459 		dev_priv->display.enable_backlight = i9xx_enable_backlight;
1460 		dev_priv->display.disable_backlight = i9xx_disable_backlight;
1461 		dev_priv->display.set_backlight = i9xx_set_backlight;
1462 		dev_priv->display.get_backlight = i9xx_get_backlight;
1463 	}
1464 }
1465 
1466 int intel_panel_init(struct intel_panel *panel,
1467 		     struct drm_display_mode *fixed_mode,
1468 		     struct drm_display_mode *downclock_mode)
1469 {
1470 	panel->fixed_mode = fixed_mode;
1471 	panel->downclock_mode = downclock_mode;
1472 
1473 	return 0;
1474 }
1475 
1476 void intel_panel_fini(struct intel_panel *panel)
1477 {
1478 	struct intel_connector *intel_connector =
1479 		container_of(panel, struct intel_connector, panel);
1480 
1481 	if (panel->fixed_mode)
1482 		drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
1483 
1484 	if (panel->downclock_mode)
1485 		drm_mode_destroy(intel_connector->base.dev,
1486 				panel->downclock_mode);
1487 }
1488 
1489 void intel_backlight_register(struct drm_device *dev)
1490 {
1491 	struct intel_connector *connector;
1492 
1493 	list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1494 		intel_backlight_device_register(connector);
1495 }
1496 
1497 void intel_backlight_unregister(struct drm_device *dev)
1498 {
1499 	struct intel_connector *connector;
1500 
1501 	list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1502 		intel_backlight_device_unregister(connector);
1503 }
1504