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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
32
33#include <linux/kernel.h>
34#include <linux/moduleparam.h>
35#include "intel_drv.h"
36
37void
38intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
39		       struct drm_display_mode *adjusted_mode)
40{
41	drm_mode_copy(adjusted_mode, fixed_mode);
42
43	drm_mode_set_crtcinfo(adjusted_mode, 0);
44}
45
46/**
47 * intel_find_panel_downclock - find the reduced downclock for LVDS in EDID
48 * @dev: drm device
49 * @fixed_mode : panel native mode
50 * @connector: LVDS/eDP connector
51 *
52 * Return downclock_avail
53 * Find the reduced downclock for LVDS/eDP in EDID.
54 */
55struct drm_display_mode *
56intel_find_panel_downclock(struct drm_device *dev,
57			struct drm_display_mode *fixed_mode,
58			struct drm_connector *connector)
59{
60	struct drm_display_mode *scan, *tmp_mode;
61	int temp_downclock;
62
63	temp_downclock = fixed_mode->clock;
64	tmp_mode = NULL;
65
66	list_for_each_entry(scan, &connector->probed_modes, head) {
67		/*
68		 * If one mode has the same resolution with the fixed_panel
69		 * mode while they have the different refresh rate, it means
70		 * that the reduced downclock is found. In such
71		 * case we can set the different FPx0/1 to dynamically select
72		 * between low and high frequency.
73		 */
74		if (scan->hdisplay == fixed_mode->hdisplay &&
75		    scan->hsync_start == fixed_mode->hsync_start &&
76		    scan->hsync_end == fixed_mode->hsync_end &&
77		    scan->htotal == fixed_mode->htotal &&
78		    scan->vdisplay == fixed_mode->vdisplay &&
79		    scan->vsync_start == fixed_mode->vsync_start &&
80		    scan->vsync_end == fixed_mode->vsync_end &&
81		    scan->vtotal == fixed_mode->vtotal) {
82			if (scan->clock < temp_downclock) {
83				/*
84				 * The downclock is already found. But we
85				 * expect to find the lower downclock.
86				 */
87				temp_downclock = scan->clock;
88				tmp_mode = scan;
89			}
90		}
91	}
92
93	if (temp_downclock < fixed_mode->clock)
94		return drm_mode_duplicate(dev, tmp_mode);
95	else
96		return NULL;
97}
98
99/* adjusted_mode has been preset to be the panel's fixed mode */
100void
101intel_pch_panel_fitting(struct intel_crtc *intel_crtc,
102			struct intel_crtc_state *pipe_config,
103			int fitting_mode)
104{
105	struct drm_display_mode *adjusted_mode;
106	int x, y, width, height;
107
108	adjusted_mode = &pipe_config->base.adjusted_mode;
109
110	x = y = width = height = 0;
111
112	/* Native modes don't need fitting */
113	if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
114	    adjusted_mode->vdisplay == pipe_config->pipe_src_h)
115		goto done;
116
117	switch (fitting_mode) {
118	case DRM_MODE_SCALE_CENTER:
119		width = pipe_config->pipe_src_w;
120		height = pipe_config->pipe_src_h;
121		x = (adjusted_mode->hdisplay - width + 1)/2;
122		y = (adjusted_mode->vdisplay - height + 1)/2;
123		break;
124
125	case DRM_MODE_SCALE_ASPECT:
126		/* Scale but preserve the aspect ratio */
127		{
128			u32 scaled_width = adjusted_mode->hdisplay
129				* pipe_config->pipe_src_h;
130			u32 scaled_height = pipe_config->pipe_src_w
131				* adjusted_mode->vdisplay;
132			if (scaled_width > scaled_height) { /* pillar */
133				width = scaled_height / pipe_config->pipe_src_h;
134				if (width & 1)
135					width++;
136				x = (adjusted_mode->hdisplay - width + 1) / 2;
137				y = 0;
138				height = adjusted_mode->vdisplay;
139			} else if (scaled_width < scaled_height) { /* letter */
140				height = scaled_width / pipe_config->pipe_src_w;
141				if (height & 1)
142				    height++;
143				y = (adjusted_mode->vdisplay - height + 1) / 2;
144				x = 0;
145				width = adjusted_mode->hdisplay;
146			} else {
147				x = y = 0;
148				width = adjusted_mode->hdisplay;
149				height = adjusted_mode->vdisplay;
150			}
151		}
152		break;
153
154	case DRM_MODE_SCALE_FULLSCREEN:
155		x = y = 0;
156		width = adjusted_mode->hdisplay;
157		height = adjusted_mode->vdisplay;
158		break;
159
160	default:
161		WARN(1, "bad panel fit mode: %d\n", fitting_mode);
162		return;
163	}
164
165done:
166	pipe_config->pch_pfit.pos = (x << 16) | y;
167	pipe_config->pch_pfit.size = (width << 16) | height;
168	pipe_config->pch_pfit.enabled = pipe_config->pch_pfit.size != 0;
169}
170
171static void
172centre_horizontally(struct drm_display_mode *mode,
173		    int width)
174{
175	u32 border, sync_pos, blank_width, sync_width;
176
177	/* keep the hsync and hblank widths constant */
178	sync_width = mode->crtc_hsync_end - mode->crtc_hsync_start;
179	blank_width = mode->crtc_hblank_end - mode->crtc_hblank_start;
180	sync_pos = (blank_width - sync_width + 1) / 2;
181
182	border = (mode->hdisplay - width + 1) / 2;
183	border += border & 1; /* make the border even */
184
185	mode->crtc_hdisplay = width;
186	mode->crtc_hblank_start = width + border;
187	mode->crtc_hblank_end = mode->crtc_hblank_start + blank_width;
188
189	mode->crtc_hsync_start = mode->crtc_hblank_start + sync_pos;
190	mode->crtc_hsync_end = mode->crtc_hsync_start + sync_width;
191}
192
193static void
194centre_vertically(struct drm_display_mode *mode,
195		  int height)
196{
197	u32 border, sync_pos, blank_width, sync_width;
198
199	/* keep the vsync and vblank widths constant */
200	sync_width = mode->crtc_vsync_end - mode->crtc_vsync_start;
201	blank_width = mode->crtc_vblank_end - mode->crtc_vblank_start;
202	sync_pos = (blank_width - sync_width + 1) / 2;
203
204	border = (mode->vdisplay - height + 1) / 2;
205
206	mode->crtc_vdisplay = height;
207	mode->crtc_vblank_start = height + border;
208	mode->crtc_vblank_end = mode->crtc_vblank_start + blank_width;
209
210	mode->crtc_vsync_start = mode->crtc_vblank_start + sync_pos;
211	mode->crtc_vsync_end = mode->crtc_vsync_start + sync_width;
212}
213
214static inline u32 panel_fitter_scaling(u32 source, u32 target)
215{
216	/*
217	 * Floating point operation is not supported. So the FACTOR
218	 * is defined, which can avoid the floating point computation
219	 * when calculating the panel ratio.
220	 */
221#define ACCURACY 12
222#define FACTOR (1 << ACCURACY)
223	u32 ratio = source * FACTOR / target;
224	return (FACTOR * ratio + FACTOR/2) / FACTOR;
225}
226
227static void i965_scale_aspect(struct intel_crtc_state *pipe_config,
228			      u32 *pfit_control)
229{
230	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
231	u32 scaled_width = adjusted_mode->hdisplay *
232		pipe_config->pipe_src_h;
233	u32 scaled_height = pipe_config->pipe_src_w *
234		adjusted_mode->vdisplay;
235
236	/* 965+ is easy, it does everything in hw */
237	if (scaled_width > scaled_height)
238		*pfit_control |= PFIT_ENABLE |
239			PFIT_SCALING_PILLAR;
240	else if (scaled_width < scaled_height)
241		*pfit_control |= PFIT_ENABLE |
242			PFIT_SCALING_LETTER;
243	else if (adjusted_mode->hdisplay != pipe_config->pipe_src_w)
244		*pfit_control |= PFIT_ENABLE | PFIT_SCALING_AUTO;
245}
246
247static void i9xx_scale_aspect(struct intel_crtc_state *pipe_config,
248			      u32 *pfit_control, u32 *pfit_pgm_ratios,
249			      u32 *border)
250{
251	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
252	u32 scaled_width = adjusted_mode->hdisplay *
253		pipe_config->pipe_src_h;
254	u32 scaled_height = pipe_config->pipe_src_w *
255		adjusted_mode->vdisplay;
256	u32 bits;
257
258	/*
259	 * For earlier chips we have to calculate the scaling
260	 * ratio by hand and program it into the
261	 * PFIT_PGM_RATIO register
262	 */
263	if (scaled_width > scaled_height) { /* pillar */
264		centre_horizontally(adjusted_mode,
265				    scaled_height /
266				    pipe_config->pipe_src_h);
267
268		*border = LVDS_BORDER_ENABLE;
269		if (pipe_config->pipe_src_h != adjusted_mode->vdisplay) {
270			bits = panel_fitter_scaling(pipe_config->pipe_src_h,
271						    adjusted_mode->vdisplay);
272
273			*pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
274					     bits << PFIT_VERT_SCALE_SHIFT);
275			*pfit_control |= (PFIT_ENABLE |
276					  VERT_INTERP_BILINEAR |
277					  HORIZ_INTERP_BILINEAR);
278		}
279	} else if (scaled_width < scaled_height) { /* letter */
280		centre_vertically(adjusted_mode,
281				  scaled_width /
282				  pipe_config->pipe_src_w);
283
284		*border = LVDS_BORDER_ENABLE;
285		if (pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
286			bits = panel_fitter_scaling(pipe_config->pipe_src_w,
287						    adjusted_mode->hdisplay);
288
289			*pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
290					     bits << PFIT_VERT_SCALE_SHIFT);
291			*pfit_control |= (PFIT_ENABLE |
292					  VERT_INTERP_BILINEAR |
293					  HORIZ_INTERP_BILINEAR);
294		}
295	} else {
296		/* Aspects match, Let hw scale both directions */
297		*pfit_control |= (PFIT_ENABLE |
298				  VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |
299				  VERT_INTERP_BILINEAR |
300				  HORIZ_INTERP_BILINEAR);
301	}
302}
303
304void intel_gmch_panel_fitting(struct intel_crtc *intel_crtc,
305			      struct intel_crtc_state *pipe_config,
306			      int fitting_mode)
307{
308	struct drm_device *dev = intel_crtc->base.dev;
309	u32 pfit_control = 0, pfit_pgm_ratios = 0, border = 0;
310	struct drm_display_mode *adjusted_mode;
311
312	adjusted_mode = &pipe_config->base.adjusted_mode;
313
314	/* Native modes don't need fitting */
315	if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
316	    adjusted_mode->vdisplay == pipe_config->pipe_src_h)
317		goto out;
318
319	switch (fitting_mode) {
320	case DRM_MODE_SCALE_CENTER:
321		/*
322		 * For centered modes, we have to calculate border widths &
323		 * heights and modify the values programmed into the CRTC.
324		 */
325		centre_horizontally(adjusted_mode, pipe_config->pipe_src_w);
326		centre_vertically(adjusted_mode, pipe_config->pipe_src_h);
327		border = LVDS_BORDER_ENABLE;
328		break;
329	case DRM_MODE_SCALE_ASPECT:
330		/* Scale but preserve the aspect ratio */
331		if (INTEL_INFO(dev)->gen >= 4)
332			i965_scale_aspect(pipe_config, &pfit_control);
333		else
334			i9xx_scale_aspect(pipe_config, &pfit_control,
335					  &pfit_pgm_ratios, &border);
336		break;
337	case DRM_MODE_SCALE_FULLSCREEN:
338		/*
339		 * Full scaling, even if it changes the aspect ratio.
340		 * Fortunately this is all done for us in hw.
341		 */
342		if (pipe_config->pipe_src_h != adjusted_mode->vdisplay ||
343		    pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
344			pfit_control |= PFIT_ENABLE;
345			if (INTEL_INFO(dev)->gen >= 4)
346				pfit_control |= PFIT_SCALING_AUTO;
347			else
348				pfit_control |= (VERT_AUTO_SCALE |
349						 VERT_INTERP_BILINEAR |
350						 HORIZ_AUTO_SCALE |
351						 HORIZ_INTERP_BILINEAR);
352		}
353		break;
354	default:
355		WARN(1, "bad panel fit mode: %d\n", fitting_mode);
356		return;
357	}
358
359	/* 965+ wants fuzzy fitting */
360	/* FIXME: handle multiple panels by failing gracefully */
361	if (INTEL_INFO(dev)->gen >= 4)
362		pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
363				 PFIT_FILTER_FUZZY);
364
365out:
366	if ((pfit_control & PFIT_ENABLE) == 0) {
367		pfit_control = 0;
368		pfit_pgm_ratios = 0;
369	}
370
371	/* Make sure pre-965 set dither correctly for 18bpp panels. */
372	if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
373		pfit_control |= PANEL_8TO6_DITHER_ENABLE;
374
375	pipe_config->gmch_pfit.control = pfit_control;
376	pipe_config->gmch_pfit.pgm_ratios = pfit_pgm_ratios;
377	pipe_config->gmch_pfit.lvds_border_bits = border;
378}
379
380enum drm_connector_status
381intel_panel_detect(struct drm_device *dev)
382{
383	struct drm_i915_private *dev_priv = dev->dev_private;
384
385	/* Assume that the BIOS does not lie through the OpRegion... */
386	if (!i915.panel_ignore_lid && dev_priv->opregion.lid_state) {
387		return ioread32(dev_priv->opregion.lid_state) & 0x1 ?
388			connector_status_connected :
389			connector_status_disconnected;
390	}
391
392	switch (i915.panel_ignore_lid) {
393	case -2:
394		return connector_status_connected;
395	case -1:
396		return connector_status_disconnected;
397	default:
398		return connector_status_unknown;
399	}
400}
401
402/**
403 * scale - scale values from one range to another
404 *
405 * @source_val: value in range [@source_min..@source_max]
406 *
407 * Return @source_val in range [@source_min..@source_max] scaled to range
408 * [@target_min..@target_max].
409 */
410static uint32_t scale(uint32_t source_val,
411		      uint32_t source_min, uint32_t source_max,
412		      uint32_t target_min, uint32_t target_max)
413{
414	uint64_t target_val;
415
416	WARN_ON(source_min > source_max);
417	WARN_ON(target_min > target_max);
418
419	/* defensive */
420	source_val = clamp(source_val, source_min, source_max);
421
422	/* avoid overflows */
423	target_val = DIV_ROUND_CLOSEST_ULL((uint64_t)(source_val - source_min) *
424			(target_max - target_min), source_max - source_min);
425	target_val += target_min;
426
427	return target_val;
428}
429
430/* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
431static inline u32 scale_user_to_hw(struct intel_connector *connector,
432				   u32 user_level, u32 user_max)
433{
434	struct intel_panel *panel = &connector->panel;
435
436	return scale(user_level, 0, user_max,
437		     panel->backlight.min, panel->backlight.max);
438}
439
440/* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
441 * to [hw_min..hw_max]. */
442static inline u32 clamp_user_to_hw(struct intel_connector *connector,
443				   u32 user_level, u32 user_max)
444{
445	struct intel_panel *panel = &connector->panel;
446	u32 hw_level;
447
448	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
449	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
450
451	return hw_level;
452}
453
454/* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
455static inline u32 scale_hw_to_user(struct intel_connector *connector,
456				   u32 hw_level, u32 user_max)
457{
458	struct intel_panel *panel = &connector->panel;
459
460	return scale(hw_level, panel->backlight.min, panel->backlight.max,
461		     0, user_max);
462}
463
464static u32 intel_panel_compute_brightness(struct intel_connector *connector,
465					  u32 val)
466{
467	struct drm_device *dev = connector->base.dev;
468	struct drm_i915_private *dev_priv = dev->dev_private;
469	struct intel_panel *panel = &connector->panel;
470
471	WARN_ON(panel->backlight.max == 0);
472
473	if (i915.invert_brightness < 0)
474		return val;
475
476	if (i915.invert_brightness > 0 ||
477	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
478		return panel->backlight.max - val;
479	}
480
481	return val;
482}
483
484static u32 bdw_get_backlight(struct intel_connector *connector)
485{
486	struct drm_device *dev = connector->base.dev;
487	struct drm_i915_private *dev_priv = dev->dev_private;
488
489	return I915_READ(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
490}
491
492static u32 pch_get_backlight(struct intel_connector *connector)
493{
494	struct drm_device *dev = connector->base.dev;
495	struct drm_i915_private *dev_priv = dev->dev_private;
496
497	return I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
498}
499
500static u32 i9xx_get_backlight(struct intel_connector *connector)
501{
502	struct drm_device *dev = connector->base.dev;
503	struct drm_i915_private *dev_priv = dev->dev_private;
504	struct intel_panel *panel = &connector->panel;
505	u32 val;
506
507	val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
508	if (INTEL_INFO(dev)->gen < 4)
509		val >>= 1;
510
511	if (panel->backlight.combination_mode) {
512		u8 lbpc;
513
514		pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
515		val *= lbpc;
516	}
517
518	return val;
519}
520
521static u32 _vlv_get_backlight(struct drm_device *dev, enum pipe pipe)
522{
523	struct drm_i915_private *dev_priv = dev->dev_private;
524
525	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
526		return 0;
527
528	return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
529}
530
531static u32 vlv_get_backlight(struct intel_connector *connector)
532{
533	struct drm_device *dev = connector->base.dev;
534	enum pipe pipe = intel_get_pipe_from_connector(connector);
535
536	return _vlv_get_backlight(dev, pipe);
537}
538
539static u32 intel_panel_get_backlight(struct intel_connector *connector)
540{
541	struct drm_device *dev = connector->base.dev;
542	struct drm_i915_private *dev_priv = dev->dev_private;
543	struct intel_panel *panel = &connector->panel;
544	u32 val = 0;
545
546	mutex_lock(&dev_priv->backlight_lock);
547
548	if (panel->backlight.enabled) {
549		val = dev_priv->display.get_backlight(connector);
550		val = intel_panel_compute_brightness(connector, val);
551	}
552
553	mutex_unlock(&dev_priv->backlight_lock);
554
555	DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
556	return val;
557}
558
559static 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
567static 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
577static 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
605static 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 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
619static void
620intel_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 */
632static 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 */
659void 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 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
696static 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
711static void i9xx_disable_backlight(struct intel_connector *connector)
712{
713	intel_panel_actually_set_backlight(connector, 0);
714}
715
716static 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
728static 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 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
744void 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
774static 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
807static 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 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
854static 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	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
885	 * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
886	 * that has backlight.
887	 */
888	if (IS_GEN2(dev))
889		I915_WRITE(BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
890}
891
892static void i965_enable_backlight(struct intel_connector *connector)
893{
894	struct drm_device *dev = connector->base.dev;
895	struct drm_i915_private *dev_priv = dev->dev_private;
896	struct intel_panel *panel = &connector->panel;
897	enum pipe pipe = intel_get_pipe_from_connector(connector);
898	u32 ctl, ctl2, freq;
899
900	ctl2 = I915_READ(BLC_PWM_CTL2);
901	if (ctl2 & BLM_PWM_ENABLE) {
902		DRM_DEBUG_KMS("backlight already enabled\n");
903		ctl2 &= ~BLM_PWM_ENABLE;
904		I915_WRITE(BLC_PWM_CTL2, ctl2);
905	}
906
907	freq = panel->backlight.max;
908	if (panel->backlight.combination_mode)
909		freq /= 0xff;
910
911	ctl = freq << 16;
912	I915_WRITE(BLC_PWM_CTL, ctl);
913
914	ctl2 = BLM_PIPE(pipe);
915	if (panel->backlight.combination_mode)
916		ctl2 |= BLM_COMBINATION_MODE;
917	if (panel->backlight.active_low_pwm)
918		ctl2 |= BLM_POLARITY_I965;
919	I915_WRITE(BLC_PWM_CTL2, ctl2);
920	POSTING_READ(BLC_PWM_CTL2);
921	I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
922
923	intel_panel_actually_set_backlight(connector, panel->backlight.level);
924}
925
926static void vlv_enable_backlight(struct intel_connector *connector)
927{
928	struct drm_device *dev = connector->base.dev;
929	struct drm_i915_private *dev_priv = dev->dev_private;
930	struct intel_panel *panel = &connector->panel;
931	enum pipe pipe = intel_get_pipe_from_connector(connector);
932	u32 ctl, ctl2;
933
934	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
935		return;
936
937	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
938	if (ctl2 & BLM_PWM_ENABLE) {
939		DRM_DEBUG_KMS("backlight already enabled\n");
940		ctl2 &= ~BLM_PWM_ENABLE;
941		I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
942	}
943
944	ctl = panel->backlight.max << 16;
945	I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
946
947	/* XXX: combine this into above write? */
948	intel_panel_actually_set_backlight(connector, panel->backlight.level);
949
950	ctl2 = 0;
951	if (panel->backlight.active_low_pwm)
952		ctl2 |= BLM_POLARITY_I965;
953	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
954	POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
955	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
956}
957
958void intel_panel_enable_backlight(struct intel_connector *connector)
959{
960	struct drm_device *dev = connector->base.dev;
961	struct drm_i915_private *dev_priv = dev->dev_private;
962	struct intel_panel *panel = &connector->panel;
963	enum pipe pipe = intel_get_pipe_from_connector(connector);
964
965	if (!panel->backlight.present)
966		return;
967
968	DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
969
970	mutex_lock(&dev_priv->backlight_lock);
971
972	WARN_ON(panel->backlight.max == 0);
973
974	if (panel->backlight.level <= panel->backlight.min) {
975		panel->backlight.level = panel->backlight.max;
976		if (panel->backlight.device)
977			panel->backlight.device->props.brightness =
978				scale_hw_to_user(connector,
979						 panel->backlight.level,
980						 panel->backlight.device->props.max_brightness);
981	}
982
983	dev_priv->display.enable_backlight(connector);
984	panel->backlight.enabled = true;
985	if (panel->backlight.device)
986		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
987
988	mutex_unlock(&dev_priv->backlight_lock);
989}
990
991#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
992static int intel_backlight_device_update_status(struct backlight_device *bd)
993{
994	struct intel_connector *connector = bl_get_data(bd);
995	struct intel_panel *panel = &connector->panel;
996	struct drm_device *dev = connector->base.dev;
997
998	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
999	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
1000		      bd->props.brightness, bd->props.max_brightness);
1001	intel_panel_set_backlight(connector, bd->props.brightness,
1002				  bd->props.max_brightness);
1003
1004	/*
1005	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
1006	 * backlight class device does not make it easy to to differentiate
1007	 * between callbacks for brightness and bl_power, so our backlight_power
1008	 * callback needs to take this into account.
1009	 */
1010	if (panel->backlight.enabled) {
1011		if (panel->backlight_power) {
1012			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
1013				bd->props.brightness != 0;
1014			panel->backlight_power(connector, enable);
1015		}
1016	} else {
1017		bd->props.power = FB_BLANK_POWERDOWN;
1018	}
1019
1020	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1021	return 0;
1022}
1023
1024static int intel_backlight_device_get_brightness(struct backlight_device *bd)
1025{
1026	struct intel_connector *connector = bl_get_data(bd);
1027	struct drm_device *dev = connector->base.dev;
1028	struct drm_i915_private *dev_priv = dev->dev_private;
1029	u32 hw_level;
1030	int ret;
1031
1032	intel_runtime_pm_get(dev_priv);
1033	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1034
1035	hw_level = intel_panel_get_backlight(connector);
1036	ret = scale_hw_to_user(connector, hw_level, bd->props.max_brightness);
1037
1038	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1039	intel_runtime_pm_put(dev_priv);
1040
1041	return ret;
1042}
1043
1044static const struct backlight_ops intel_backlight_device_ops = {
1045	.update_status = intel_backlight_device_update_status,
1046	.get_brightness = intel_backlight_device_get_brightness,
1047};
1048
1049static int intel_backlight_device_register(struct intel_connector *connector)
1050{
1051	struct intel_panel *panel = &connector->panel;
1052	struct backlight_properties props;
1053
1054	if (WARN_ON(panel->backlight.device))
1055		return -ENODEV;
1056
1057	if (!panel->backlight.present)
1058		return 0;
1059
1060	WARN_ON(panel->backlight.max == 0);
1061
1062	memset(&props, 0, sizeof(props));
1063	props.type = BACKLIGHT_RAW;
1064
1065	/*
1066	 * Note: Everything should work even if the backlight device max
1067	 * presented to the userspace is arbitrarily chosen.
1068	 */
1069	props.max_brightness = panel->backlight.max;
1070	props.brightness = scale_hw_to_user(connector,
1071					    panel->backlight.level,
1072					    props.max_brightness);
1073
1074	if (panel->backlight.enabled)
1075		props.power = FB_BLANK_UNBLANK;
1076	else
1077		props.power = FB_BLANK_POWERDOWN;
1078
1079	/*
1080	 * Note: using the same name independent of the connector prevents
1081	 * registration of multiple backlight devices in the driver.
1082	 */
1083	panel->backlight.device =
1084		backlight_device_register("intel_backlight",
1085					  connector->base.kdev,
1086					  connector,
1087					  &intel_backlight_device_ops, &props);
1088
1089	if (IS_ERR(panel->backlight.device)) {
1090		DRM_ERROR("Failed to register backlight: %ld\n",
1091			  PTR_ERR(panel->backlight.device));
1092		panel->backlight.device = NULL;
1093		return -ENODEV;
1094	}
1095
1096	DRM_DEBUG_KMS("Connector %s backlight sysfs interface registered\n",
1097		      connector->base.name);
1098
1099	return 0;
1100}
1101
1102static void intel_backlight_device_unregister(struct intel_connector *connector)
1103{
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}
1111#else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1112static int intel_backlight_device_register(struct intel_connector *connector)
1113{
1114	return 0;
1115}
1116static void intel_backlight_device_unregister(struct intel_connector *connector)
1117{
1118}
1119#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1120
1121/*
1122 * Note: The setup hooks can't assume pipe is set!
1123 *
1124 * XXX: Query mode clock or hardware clock and program PWM modulation frequency
1125 * appropriately when it's 0. Use VBT and/or sane defaults.
1126 */
1127static u32 get_backlight_min_vbt(struct intel_connector *connector)
1128{
1129	struct drm_device *dev = connector->base.dev;
1130	struct drm_i915_private *dev_priv = dev->dev_private;
1131	struct intel_panel *panel = &connector->panel;
1132	int min;
1133
1134	WARN_ON(panel->backlight.max == 0);
1135
1136	/*
1137	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
1138	 * to problems. There are such machines out there. Either our
1139	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1140	 * against this by letting the minimum be at most (arbitrarily chosen)
1141	 * 25% of the max.
1142	 */
1143	min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
1144	if (min != dev_priv->vbt.backlight.min_brightness) {
1145		DRM_DEBUG_KMS("clamping VBT min backlight %d/255 to %d/255\n",
1146			      dev_priv->vbt.backlight.min_brightness, min);
1147	}
1148
1149	/* vbt value is a coefficient in range [0..255] */
1150	return scale(min, 0, 255, 0, panel->backlight.max);
1151}
1152
1153static int bdw_setup_backlight(struct intel_connector *connector, enum pipe unused)
1154{
1155	struct drm_device *dev = connector->base.dev;
1156	struct drm_i915_private *dev_priv = dev->dev_private;
1157	struct intel_panel *panel = &connector->panel;
1158	u32 pch_ctl1, pch_ctl2, val;
1159
1160	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1161	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1162
1163	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1164	panel->backlight.max = pch_ctl2 >> 16;
1165	if (!panel->backlight.max)
1166		return -ENODEV;
1167
1168	panel->backlight.min = get_backlight_min_vbt(connector);
1169
1170	val = bdw_get_backlight(connector);
1171	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1172
1173	panel->backlight.enabled = (pch_ctl1 & BLM_PCH_PWM_ENABLE) &&
1174		panel->backlight.level != 0;
1175
1176	return 0;
1177}
1178
1179static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
1180{
1181	struct drm_device *dev = connector->base.dev;
1182	struct drm_i915_private *dev_priv = dev->dev_private;
1183	struct intel_panel *panel = &connector->panel;
1184	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1185
1186	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1187	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1188
1189	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1190	panel->backlight.max = pch_ctl2 >> 16;
1191	if (!panel->backlight.max)
1192		return -ENODEV;
1193
1194	panel->backlight.min = get_backlight_min_vbt(connector);
1195
1196	val = pch_get_backlight(connector);
1197	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1198
1199	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
1200	panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1201		(pch_ctl1 & BLM_PCH_PWM_ENABLE) && panel->backlight.level != 0;
1202
1203	return 0;
1204}
1205
1206static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
1207{
1208	struct drm_device *dev = connector->base.dev;
1209	struct drm_i915_private *dev_priv = dev->dev_private;
1210	struct intel_panel *panel = &connector->panel;
1211	u32 ctl, val;
1212
1213	ctl = I915_READ(BLC_PWM_CTL);
1214
1215	if (IS_GEN2(dev) || IS_I915GM(dev) || IS_I945GM(dev))
1216		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1217
1218	if (IS_PINEVIEW(dev))
1219		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1220
1221	panel->backlight.max = ctl >> 17;
1222	if (panel->backlight.combination_mode)
1223		panel->backlight.max *= 0xff;
1224
1225	if (!panel->backlight.max)
1226		return -ENODEV;
1227
1228	panel->backlight.min = get_backlight_min_vbt(connector);
1229
1230	val = i9xx_get_backlight(connector);
1231	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1232
1233	panel->backlight.enabled = panel->backlight.level != 0;
1234
1235	return 0;
1236}
1237
1238static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
1239{
1240	struct drm_device *dev = connector->base.dev;
1241	struct drm_i915_private *dev_priv = dev->dev_private;
1242	struct intel_panel *panel = &connector->panel;
1243	u32 ctl, ctl2, val;
1244
1245	ctl2 = I915_READ(BLC_PWM_CTL2);
1246	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1247	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1248
1249	ctl = I915_READ(BLC_PWM_CTL);
1250	panel->backlight.max = ctl >> 16;
1251	if (panel->backlight.combination_mode)
1252		panel->backlight.max *= 0xff;
1253
1254	if (!panel->backlight.max)
1255		return -ENODEV;
1256
1257	panel->backlight.min = get_backlight_min_vbt(connector);
1258
1259	val = i9xx_get_backlight(connector);
1260	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1261
1262	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1263		panel->backlight.level != 0;
1264
1265	return 0;
1266}
1267
1268static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1269{
1270	struct drm_device *dev = connector->base.dev;
1271	struct drm_i915_private *dev_priv = dev->dev_private;
1272	struct intel_panel *panel = &connector->panel;
1273	enum pipe p;
1274	u32 ctl, ctl2, val;
1275
1276	for_each_pipe(dev_priv, p) {
1277		u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
1278
1279		/* Skip if the modulation freq is already set */
1280		if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
1281			continue;
1282
1283		cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
1284		I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
1285			   cur_val);
1286	}
1287
1288	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
1289		return -ENODEV;
1290
1291	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
1292	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1293
1294	ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
1295	panel->backlight.max = ctl >> 16;
1296	if (!panel->backlight.max)
1297		return -ENODEV;
1298
1299	panel->backlight.min = get_backlight_min_vbt(connector);
1300
1301	val = _vlv_get_backlight(dev, pipe);
1302	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1303
1304	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1305		panel->backlight.level != 0;
1306
1307	return 0;
1308}
1309
1310int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
1311{
1312	struct drm_device *dev = connector->dev;
1313	struct drm_i915_private *dev_priv = dev->dev_private;
1314	struct intel_connector *intel_connector = to_intel_connector(connector);
1315	struct intel_panel *panel = &intel_connector->panel;
1316	int ret;
1317
1318	if (!dev_priv->vbt.backlight.present) {
1319		if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
1320			DRM_DEBUG_KMS("no backlight present per VBT, but present per quirk\n");
1321		} else {
1322			DRM_DEBUG_KMS("no backlight present per VBT\n");
1323			return 0;
1324		}
1325	}
1326
1327	/* set level and max in panel struct */
1328	mutex_lock(&dev_priv->backlight_lock);
1329	ret = dev_priv->display.setup_backlight(intel_connector, pipe);
1330	mutex_unlock(&dev_priv->backlight_lock);
1331
1332	if (ret) {
1333		DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
1334			      connector->name);
1335		return ret;
1336	}
1337
1338	panel->backlight.present = true;
1339
1340	DRM_DEBUG_KMS("Connector %s backlight initialized, %s, brightness %u/%u\n",
1341		      connector->name,
1342		      panel->backlight.enabled ? "enabled" : "disabled",
1343		      panel->backlight.level, panel->backlight.max);
1344
1345	return 0;
1346}
1347
1348void intel_panel_destroy_backlight(struct drm_connector *connector)
1349{
1350	struct intel_connector *intel_connector = to_intel_connector(connector);
1351	struct intel_panel *panel = &intel_connector->panel;
1352
1353	panel->backlight.present = false;
1354}
1355
1356/* Set up chip specific backlight functions */
1357void intel_panel_init_backlight_funcs(struct drm_device *dev)
1358{
1359	struct drm_i915_private *dev_priv = dev->dev_private;
1360
1361	if (IS_BROADWELL(dev) || (INTEL_INFO(dev)->gen >= 9)) {
1362		dev_priv->display.setup_backlight = bdw_setup_backlight;
1363		dev_priv->display.enable_backlight = bdw_enable_backlight;
1364		dev_priv->display.disable_backlight = pch_disable_backlight;
1365		dev_priv->display.set_backlight = bdw_set_backlight;
1366		dev_priv->display.get_backlight = bdw_get_backlight;
1367	} else if (HAS_PCH_SPLIT(dev)) {
1368		dev_priv->display.setup_backlight = pch_setup_backlight;
1369		dev_priv->display.enable_backlight = pch_enable_backlight;
1370		dev_priv->display.disable_backlight = pch_disable_backlight;
1371		dev_priv->display.set_backlight = pch_set_backlight;
1372		dev_priv->display.get_backlight = pch_get_backlight;
1373	} else if (IS_VALLEYVIEW(dev)) {
1374		dev_priv->display.setup_backlight = vlv_setup_backlight;
1375		dev_priv->display.enable_backlight = vlv_enable_backlight;
1376		dev_priv->display.disable_backlight = vlv_disable_backlight;
1377		dev_priv->display.set_backlight = vlv_set_backlight;
1378		dev_priv->display.get_backlight = vlv_get_backlight;
1379	} else if (IS_GEN4(dev)) {
1380		dev_priv->display.setup_backlight = i965_setup_backlight;
1381		dev_priv->display.enable_backlight = i965_enable_backlight;
1382		dev_priv->display.disable_backlight = i965_disable_backlight;
1383		dev_priv->display.set_backlight = i9xx_set_backlight;
1384		dev_priv->display.get_backlight = i9xx_get_backlight;
1385	} else {
1386		dev_priv->display.setup_backlight = i9xx_setup_backlight;
1387		dev_priv->display.enable_backlight = i9xx_enable_backlight;
1388		dev_priv->display.disable_backlight = i9xx_disable_backlight;
1389		dev_priv->display.set_backlight = i9xx_set_backlight;
1390		dev_priv->display.get_backlight = i9xx_get_backlight;
1391	}
1392}
1393
1394int intel_panel_init(struct intel_panel *panel,
1395		     struct drm_display_mode *fixed_mode,
1396		     struct drm_display_mode *downclock_mode)
1397{
1398	panel->fixed_mode = fixed_mode;
1399	panel->downclock_mode = downclock_mode;
1400
1401	return 0;
1402}
1403
1404void intel_panel_fini(struct intel_panel *panel)
1405{
1406	struct intel_connector *intel_connector =
1407		container_of(panel, struct intel_connector, panel);
1408
1409	if (panel->fixed_mode)
1410		drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
1411
1412	if (panel->downclock_mode)
1413		drm_mode_destroy(intel_connector->base.dev,
1414				panel->downclock_mode);
1415}
1416
1417void intel_backlight_register(struct drm_device *dev)
1418{
1419	struct intel_connector *connector;
1420
1421	list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1422		intel_backlight_device_register(connector);
1423}
1424
1425void intel_backlight_unregister(struct drm_device *dev)
1426{
1427	struct intel_connector *connector;
1428
1429	list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1430		intel_backlight_device_unregister(connector);
1431}
1432