xref: /dragonfly/sys/dev/drm/i915/intel_panel.c (revision ed36d35d)
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 
32 #include <linux/kernel.h>
33 #include <linux/moduleparam.h>
34 #include <linux/pwm.h>
35 #include "intel_drv.h"
36 
37 #define CRC_PMIC_PWM_PERIOD_NS	21333
38 
39 void
40 intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
41 		       struct drm_display_mode *adjusted_mode)
42 {
43 	drm_mode_copy(adjusted_mode, fixed_mode);
44 
45 	drm_mode_set_crtcinfo(adjusted_mode, 0);
46 }
47 
48 /**
49  * intel_find_panel_downclock - find the reduced downclock for LVDS in EDID
50  * @dev: drm device
51  * @fixed_mode : panel native mode
52  * @connector: LVDS/eDP connector
53  *
54  * Return downclock_avail
55  * Find the reduced downclock for LVDS/eDP in EDID.
56  */
57 struct drm_display_mode *
58 intel_find_panel_downclock(struct drm_device *dev,
59 			struct drm_display_mode *fixed_mode,
60 			struct drm_connector *connector)
61 {
62 	struct drm_display_mode *scan, *tmp_mode;
63 	int temp_downclock;
64 
65 	temp_downclock = fixed_mode->clock;
66 	tmp_mode = NULL;
67 
68 	list_for_each_entry(scan, &connector->probed_modes, head) {
69 		/*
70 		 * If one mode has the same resolution with the fixed_panel
71 		 * mode while they have the different refresh rate, it means
72 		 * that the reduced downclock is found. In such
73 		 * case we can set the different FPx0/1 to dynamically select
74 		 * between low and high frequency.
75 		 */
76 		if (scan->hdisplay == fixed_mode->hdisplay &&
77 		    scan->hsync_start == fixed_mode->hsync_start &&
78 		    scan->hsync_end == fixed_mode->hsync_end &&
79 		    scan->htotal == fixed_mode->htotal &&
80 		    scan->vdisplay == fixed_mode->vdisplay &&
81 		    scan->vsync_start == fixed_mode->vsync_start &&
82 		    scan->vsync_end == fixed_mode->vsync_end &&
83 		    scan->vtotal == fixed_mode->vtotal) {
84 			if (scan->clock < temp_downclock) {
85 				/*
86 				 * The downclock is already found. But we
87 				 * expect to find the lower downclock.
88 				 */
89 				temp_downclock = scan->clock;
90 				tmp_mode = scan;
91 			}
92 		}
93 	}
94 
95 	if (temp_downclock < fixed_mode->clock)
96 		return drm_mode_duplicate(dev, tmp_mode);
97 	else
98 		return NULL;
99 }
100 
101 /* adjusted_mode has been preset to be the panel's fixed mode */
102 void
103 intel_pch_panel_fitting(struct intel_crtc *intel_crtc,
104 			struct intel_crtc_state *pipe_config,
105 			int fitting_mode)
106 {
107 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
108 	int x = 0, y = 0, width = 0, height = 0;
109 
110 	/* Native modes don't need fitting */
111 	if (adjusted_mode->crtc_hdisplay == pipe_config->pipe_src_w &&
112 	    adjusted_mode->crtc_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->crtc_hdisplay - width + 1)/2;
120 		y = (adjusted_mode->crtc_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->crtc_hdisplay
127 				* pipe_config->pipe_src_h;
128 			u32 scaled_height = pipe_config->pipe_src_w
129 				* adjusted_mode->crtc_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->crtc_hdisplay - width + 1) / 2;
135 				y = 0;
136 				height = adjusted_mode->crtc_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->crtc_vdisplay - height + 1) / 2;
142 				x = 0;
143 				width = adjusted_mode->crtc_hdisplay;
144 			} else {
145 				x = y = 0;
146 				width = adjusted_mode->crtc_hdisplay;
147 				height = adjusted_mode->crtc_vdisplay;
148 			}
149 		}
150 		break;
151 
152 	case DRM_MODE_SCALE_FULLSCREEN:
153 		x = y = 0;
154 		width = adjusted_mode->crtc_hdisplay;
155 		height = adjusted_mode->crtc_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 *adjusted_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 = adjusted_mode->crtc_hsync_end - adjusted_mode->crtc_hsync_start;
177 	blank_width = adjusted_mode->crtc_hblank_end - adjusted_mode->crtc_hblank_start;
178 	sync_pos = (blank_width - sync_width + 1) / 2;
179 
180 	border = (adjusted_mode->crtc_hdisplay - width + 1) / 2;
181 	border += border & 1; /* make the border even */
182 
183 	adjusted_mode->crtc_hdisplay = width;
184 	adjusted_mode->crtc_hblank_start = width + border;
185 	adjusted_mode->crtc_hblank_end = adjusted_mode->crtc_hblank_start + blank_width;
186 
187 	adjusted_mode->crtc_hsync_start = adjusted_mode->crtc_hblank_start + sync_pos;
188 	adjusted_mode->crtc_hsync_end = adjusted_mode->crtc_hsync_start + sync_width;
189 }
190 
191 static void
192 centre_vertically(struct drm_display_mode *adjusted_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 = adjusted_mode->crtc_vsync_end - adjusted_mode->crtc_vsync_start;
199 	blank_width = adjusted_mode->crtc_vblank_end - adjusted_mode->crtc_vblank_start;
200 	sync_pos = (blank_width - sync_width + 1) / 2;
201 
202 	border = (adjusted_mode->crtc_vdisplay - height + 1) / 2;
203 
204 	adjusted_mode->crtc_vdisplay = height;
205 	adjusted_mode->crtc_vblank_start = height + border;
206 	adjusted_mode->crtc_vblank_end = adjusted_mode->crtc_vblank_start + blank_width;
207 
208 	adjusted_mode->crtc_vsync_start = adjusted_mode->crtc_vblank_start + sync_pos;
209 	adjusted_mode->crtc_vsync_end = adjusted_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 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
229 	u32 scaled_width = adjusted_mode->crtc_hdisplay *
230 		pipe_config->pipe_src_h;
231 	u32 scaled_height = pipe_config->pipe_src_w *
232 		adjusted_mode->crtc_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->crtc_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->crtc_hdisplay *
251 		pipe_config->pipe_src_h;
252 	u32 scaled_height = pipe_config->pipe_src_w *
253 		adjusted_mode->crtc_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->crtc_vdisplay) {
268 			bits = panel_fitter_scaling(pipe_config->pipe_src_h,
269 						    adjusted_mode->crtc_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->crtc_hdisplay) {
284 			bits = panel_fitter_scaling(pipe_config->pipe_src_w,
285 						    adjusted_mode->crtc_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 = &pipe_config->base.adjusted_mode;
309 
310 	/* Native modes don't need fitting */
311 	if (adjusted_mode->crtc_hdisplay == pipe_config->pipe_src_w &&
312 	    adjusted_mode->crtc_vdisplay == pipe_config->pipe_src_h)
313 		goto out;
314 
315 	switch (fitting_mode) {
316 	case DRM_MODE_SCALE_CENTER:
317 		/*
318 		 * For centered modes, we have to calculate border widths &
319 		 * heights and modify the values programmed into the CRTC.
320 		 */
321 		centre_horizontally(adjusted_mode, pipe_config->pipe_src_w);
322 		centre_vertically(adjusted_mode, pipe_config->pipe_src_h);
323 		border = LVDS_BORDER_ENABLE;
324 		break;
325 	case DRM_MODE_SCALE_ASPECT:
326 		/* Scale but preserve the aspect ratio */
327 		if (INTEL_INFO(dev)->gen >= 4)
328 			i965_scale_aspect(pipe_config, &pfit_control);
329 		else
330 			i9xx_scale_aspect(pipe_config, &pfit_control,
331 					  &pfit_pgm_ratios, &border);
332 		break;
333 	case DRM_MODE_SCALE_FULLSCREEN:
334 		/*
335 		 * Full scaling, even if it changes the aspect ratio.
336 		 * Fortunately this is all done for us in hw.
337 		 */
338 		if (pipe_config->pipe_src_h != adjusted_mode->crtc_vdisplay ||
339 		    pipe_config->pipe_src_w != adjusted_mode->crtc_hdisplay) {
340 			pfit_control |= PFIT_ENABLE;
341 			if (INTEL_INFO(dev)->gen >= 4)
342 				pfit_control |= PFIT_SCALING_AUTO;
343 			else
344 				pfit_control |= (VERT_AUTO_SCALE |
345 						 VERT_INTERP_BILINEAR |
346 						 HORIZ_AUTO_SCALE |
347 						 HORIZ_INTERP_BILINEAR);
348 		}
349 		break;
350 	default:
351 		WARN(1, "bad panel fit mode: %d\n", fitting_mode);
352 		return;
353 	}
354 
355 	/* 965+ wants fuzzy fitting */
356 	/* FIXME: handle multiple panels by failing gracefully */
357 	if (INTEL_INFO(dev)->gen >= 4)
358 		pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
359 				 PFIT_FILTER_FUZZY);
360 
361 out:
362 	if ((pfit_control & PFIT_ENABLE) == 0) {
363 		pfit_control = 0;
364 		pfit_pgm_ratios = 0;
365 	}
366 
367 	/* Make sure pre-965 set dither correctly for 18bpp panels. */
368 	if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
369 		pfit_control |= PANEL_8TO6_DITHER_ENABLE;
370 
371 	pipe_config->gmch_pfit.control = pfit_control;
372 	pipe_config->gmch_pfit.pgm_ratios = pfit_pgm_ratios;
373 	pipe_config->gmch_pfit.lvds_border_bits = border;
374 }
375 
376 enum drm_connector_status
377 intel_panel_detect(struct drm_device *dev)
378 {
379 	struct drm_i915_private *dev_priv = dev->dev_private;
380 
381 	/* Assume that the BIOS does not lie through the OpRegion... */
382 	if (!i915.panel_ignore_lid && dev_priv->opregion.lid_state) {
383 		return *dev_priv->opregion.lid_state & 0x1 ?
384 			connector_status_connected :
385 			connector_status_disconnected;
386 	}
387 
388 	switch (i915.panel_ignore_lid) {
389 	case -2:
390 		return connector_status_connected;
391 	case -1:
392 		return connector_status_disconnected;
393 	default:
394 		return connector_status_unknown;
395 	}
396 }
397 
398 /**
399  * scale - scale values from one range to another
400  *
401  * @source_val: value in range [@source_min..@source_max]
402  *
403  * Return @source_val in range [@source_min..@source_max] scaled to range
404  * [@target_min..@target_max].
405  */
406 static uint32_t scale(uint32_t source_val,
407 		      uint32_t source_min, uint32_t source_max,
408 		      uint32_t target_min, uint32_t target_max)
409 {
410 	uint64_t target_val;
411 
412 	WARN_ON(source_min > source_max);
413 	WARN_ON(target_min > target_max);
414 
415 	/* defensive */
416 	source_val = clamp(source_val, source_min, source_max);
417 
418 	/* avoid overflows */
419 	target_val = DIV_ROUND_CLOSEST_ULL((uint64_t)(source_val - source_min) *
420 			(target_max - target_min), source_max - source_min);
421 	target_val += target_min;
422 
423 	return target_val;
424 }
425 
426 /* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
427 static inline u32 scale_user_to_hw(struct intel_connector *connector,
428 				   u32 user_level, u32 user_max)
429 {
430 	struct intel_panel *panel = &connector->panel;
431 
432 	return scale(user_level, 0, user_max,
433 		     panel->backlight.min, panel->backlight.max);
434 }
435 
436 /* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
437  * to [hw_min..hw_max]. */
438 static inline u32 clamp_user_to_hw(struct intel_connector *connector,
439 				   u32 user_level, u32 user_max)
440 {
441 	struct intel_panel *panel = &connector->panel;
442 	u32 hw_level;
443 
444 	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
445 	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
446 
447 	return hw_level;
448 }
449 
450 /* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
451 static inline u32 scale_hw_to_user(struct intel_connector *connector,
452 				   u32 hw_level, u32 user_max)
453 {
454 	struct intel_panel *panel = &connector->panel;
455 
456 	return scale(hw_level, panel->backlight.min, panel->backlight.max,
457 		     0, user_max);
458 }
459 
460 static u32 intel_panel_compute_brightness(struct intel_connector *connector,
461 					  u32 val)
462 {
463 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
464 	struct intel_panel *panel = &connector->panel;
465 
466 	WARN_ON(panel->backlight.max == 0);
467 
468 	if (i915.invert_brightness < 0)
469 		return val;
470 
471 	if (i915.invert_brightness > 0 ||
472 	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
473 		return panel->backlight.max - val;
474 	}
475 
476 	return val;
477 }
478 
479 static u32 lpt_get_backlight(struct intel_connector *connector)
480 {
481 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
482 
483 	return I915_READ(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
484 }
485 
486 static u32 pch_get_backlight(struct intel_connector *connector)
487 {
488 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
489 
490 	return I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
491 }
492 
493 static u32 i9xx_get_backlight(struct intel_connector *connector)
494 {
495 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
496 	struct intel_panel *panel = &connector->panel;
497 	u32 val;
498 
499 	val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
500 	if (INTEL_INFO(dev_priv)->gen < 4)
501 		val >>= 1;
502 
503 	if (panel->backlight.combination_mode) {
504 		u8 lbpc;
505 
506 		pci_read_config_byte(dev_priv->dev->pdev, LBPC, &lbpc);
507 		val *= lbpc;
508 	}
509 
510 	return val;
511 }
512 
513 static u32 _vlv_get_backlight(struct drm_i915_private *dev_priv, enum i915_pipe pipe)
514 {
515 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
516 		return 0;
517 
518 	return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
519 }
520 
521 static u32 vlv_get_backlight(struct intel_connector *connector)
522 {
523 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
524 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
525 
526 	return _vlv_get_backlight(dev_priv, pipe);
527 }
528 
529 static u32 bxt_get_backlight(struct intel_connector *connector)
530 {
531 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
532 	struct intel_panel *panel = &connector->panel;
533 
534 	return I915_READ(BXT_BLC_PWM_DUTY(panel->backlight.controller));
535 }
536 
537 static u32 pwm_get_backlight(struct intel_connector *connector)
538 {
539 	struct intel_panel *panel = &connector->panel;
540 	int duty_ns;
541 
542 	duty_ns = pwm_get_duty_cycle(panel->backlight.pwm);
543 	return DIV_ROUND_UP(duty_ns * 100, CRC_PMIC_PWM_PERIOD_NS);
544 }
545 
546 #if 0
547 static u32 intel_panel_get_backlight(struct intel_connector *connector)
548 {
549 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
550 	struct intel_panel *panel = &connector->panel;
551 	u32 val = 0;
552 
553 	mutex_lock(&dev_priv->backlight_lock);
554 
555 	if (panel->backlight.enabled) {
556 		val = panel->backlight.get(connector);
557 		val = intel_panel_compute_brightness(connector, val);
558 	}
559 
560 	mutex_unlock(&dev_priv->backlight_lock);
561 
562 	DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
563 	return val;
564 }
565 #endif
566 
567 static void lpt_set_backlight(struct intel_connector *connector, u32 level)
568 {
569 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
570 	u32 val = I915_READ(BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
571 	I915_WRITE(BLC_PWM_PCH_CTL2, val | level);
572 }
573 
574 static void pch_set_backlight(struct intel_connector *connector, u32 level)
575 {
576 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
577 	u32 tmp;
578 
579 	tmp = I915_READ(BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
580 	I915_WRITE(BLC_PWM_CPU_CTL, tmp | level);
581 }
582 
583 static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
584 {
585 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
586 	struct intel_panel *panel = &connector->panel;
587 	u32 tmp, mask;
588 
589 	WARN_ON(panel->backlight.max == 0);
590 
591 	if (panel->backlight.combination_mode) {
592 		u8 lbpc;
593 
594 		lbpc = level * 0xfe / panel->backlight.max + 1;
595 		level /= lbpc;
596 		pci_write_config_byte(dev_priv->dev->pdev, LBPC, lbpc);
597 	}
598 
599 	if (IS_GEN4(dev_priv)) {
600 		mask = BACKLIGHT_DUTY_CYCLE_MASK;
601 	} else {
602 		level <<= 1;
603 		mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
604 	}
605 
606 	tmp = I915_READ(BLC_PWM_CTL) & ~mask;
607 	I915_WRITE(BLC_PWM_CTL, tmp | level);
608 }
609 
610 static void vlv_set_backlight(struct intel_connector *connector, u32 level)
611 {
612 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
613 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
614 	u32 tmp;
615 
616 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
617 		return;
618 
619 	tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
620 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
621 }
622 
623 static void bxt_set_backlight(struct intel_connector *connector, u32 level)
624 {
625 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
626 	struct intel_panel *panel = &connector->panel;
627 
628 	I915_WRITE(BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
629 }
630 
631 static void pwm_set_backlight(struct intel_connector *connector, u32 level)
632 {
633 	struct intel_panel *panel = &connector->panel;
634 	int duty_ns = DIV_ROUND_UP(level * CRC_PMIC_PWM_PERIOD_NS, 100);
635 
636 	pwm_config(panel->backlight.pwm, duty_ns, CRC_PMIC_PWM_PERIOD_NS);
637 }
638 
639 static void
640 intel_panel_actually_set_backlight(struct intel_connector *connector, u32 level)
641 {
642 	struct intel_panel *panel = &connector->panel;
643 
644 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
645 
646 	level = intel_panel_compute_brightness(connector, level);
647 	panel->backlight.set(connector, level);
648 }
649 
650 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
651 static void intel_panel_set_backlight(struct intel_connector *connector,
652 				      u32 user_level, u32 user_max)
653 {
654 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
655 	struct intel_panel *panel = &connector->panel;
656 	u32 hw_level;
657 
658 	if (!panel->backlight.present)
659 		return;
660 
661 	mutex_lock(&dev_priv->backlight_lock);
662 
663 	WARN_ON(panel->backlight.max == 0);
664 
665 	hw_level = scale_user_to_hw(connector, user_level, user_max);
666 	panel->backlight.level = hw_level;
667 
668 	if (panel->backlight.enabled)
669 		intel_panel_actually_set_backlight(connector, hw_level);
670 
671 	mutex_unlock(&dev_priv->backlight_lock);
672 }
673 
674 /* set backlight brightness to level in range [0..max], assuming hw min is
675  * respected.
676  */
677 void intel_panel_set_backlight_acpi(struct intel_connector *connector,
678 				    u32 user_level, u32 user_max)
679 {
680 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
681 	struct intel_panel *panel = &connector->panel;
682 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
683 	u32 hw_level;
684 
685 	/*
686 	 * INVALID_PIPE may occur during driver init because
687 	 * connection_mutex isn't held across the entire backlight
688 	 * setup + modeset readout, and the BIOS can issue the
689 	 * requests at any time.
690 	 */
691 	if (!panel->backlight.present || pipe == INVALID_PIPE)
692 		return;
693 
694 	mutex_lock(&dev_priv->backlight_lock);
695 
696 	WARN_ON(panel->backlight.max == 0);
697 
698 	hw_level = clamp_user_to_hw(connector, user_level, user_max);
699 	panel->backlight.level = hw_level;
700 
701 	if (panel->backlight.device)
702 		panel->backlight.device->props.brightness =
703 			scale_hw_to_user(connector,
704 					 panel->backlight.level,
705 					 panel->backlight.device->props.max_brightness);
706 
707 	if (panel->backlight.enabled)
708 		intel_panel_actually_set_backlight(connector, hw_level);
709 
710 	mutex_unlock(&dev_priv->backlight_lock);
711 }
712 
713 static void lpt_disable_backlight(struct intel_connector *connector)
714 {
715 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
716 	u32 tmp;
717 
718 	intel_panel_actually_set_backlight(connector, 0);
719 
720 	/*
721 	 * Although we don't support or enable CPU PWM with LPT/SPT based
722 	 * systems, it may have been enabled prior to loading the
723 	 * driver. Disable to avoid warnings on LCPLL disable.
724 	 *
725 	 * This needs rework if we need to add support for CPU PWM on PCH split
726 	 * platforms.
727 	 */
728 	tmp = I915_READ(BLC_PWM_CPU_CTL2);
729 	if (tmp & BLM_PWM_ENABLE) {
730 		DRM_DEBUG_KMS("cpu backlight was enabled, disabling\n");
731 		I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
732 	}
733 
734 	tmp = I915_READ(BLC_PWM_PCH_CTL1);
735 	I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
736 }
737 
738 static void pch_disable_backlight(struct intel_connector *connector)
739 {
740 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
741 	u32 tmp;
742 
743 	intel_panel_actually_set_backlight(connector, 0);
744 
745 	tmp = I915_READ(BLC_PWM_CPU_CTL2);
746 	I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
747 
748 	tmp = I915_READ(BLC_PWM_PCH_CTL1);
749 	I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
750 }
751 
752 static void i9xx_disable_backlight(struct intel_connector *connector)
753 {
754 	intel_panel_actually_set_backlight(connector, 0);
755 }
756 
757 static void i965_disable_backlight(struct intel_connector *connector)
758 {
759 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
760 	u32 tmp;
761 
762 	intel_panel_actually_set_backlight(connector, 0);
763 
764 	tmp = I915_READ(BLC_PWM_CTL2);
765 	I915_WRITE(BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
766 }
767 
768 static void vlv_disable_backlight(struct intel_connector *connector)
769 {
770 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
771 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
772 	u32 tmp;
773 
774 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
775 		return;
776 
777 	intel_panel_actually_set_backlight(connector, 0);
778 
779 	tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
780 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
781 }
782 
783 static void bxt_disable_backlight(struct intel_connector *connector)
784 {
785 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
786 	struct intel_panel *panel = &connector->panel;
787 	u32 tmp, val;
788 
789 	intel_panel_actually_set_backlight(connector, 0);
790 
791 	tmp = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
792 	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
793 			tmp & ~BXT_BLC_PWM_ENABLE);
794 
795 	if (panel->backlight.controller == 1) {
796 		val = I915_READ(UTIL_PIN_CTL);
797 		val &= ~UTIL_PIN_ENABLE;
798 		I915_WRITE(UTIL_PIN_CTL, val);
799 	}
800 }
801 
802 static void pwm_disable_backlight(struct intel_connector *connector)
803 {
804 	struct intel_panel *panel = &connector->panel;
805 
806 	/* Disable the backlight */
807 	pwm_config(panel->backlight.pwm, 0, CRC_PMIC_PWM_PERIOD_NS);
808 	usleep_range(2000, 3000);
809 	pwm_disable(panel->backlight.pwm);
810 }
811 
812 void intel_panel_disable_backlight(struct intel_connector *connector)
813 {
814 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
815 	struct intel_panel *panel = &connector->panel;
816 
817 	if (!panel->backlight.present)
818 		return;
819 
820 	/*
821 	 * Do not disable backlight on the vga_switcheroo path. When switching
822 	 * away from i915, the other client may depend on i915 to handle the
823 	 * backlight. This will leave the backlight on unnecessarily when
824 	 * another client is not activated.
825 	 */
826 	if (dev_priv->dev->switch_power_state == DRM_SWITCH_POWER_CHANGING) {
827 		DRM_DEBUG_DRIVER("Skipping backlight disable on vga switch\n");
828 		return;
829 	}
830 
831 	mutex_lock(&dev_priv->backlight_lock);
832 
833 	if (panel->backlight.device)
834 		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
835 	panel->backlight.enabled = false;
836 	panel->backlight.disable(connector);
837 
838 	mutex_unlock(&dev_priv->backlight_lock);
839 }
840 
841 static void lpt_enable_backlight(struct intel_connector *connector)
842 {
843 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
844 	struct intel_panel *panel = &connector->panel;
845 	u32 pch_ctl1, pch_ctl2;
846 
847 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
848 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
849 		DRM_DEBUG_KMS("pch backlight already enabled\n");
850 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
851 		I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
852 	}
853 
854 	pch_ctl2 = panel->backlight.max << 16;
855 	I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
856 
857 	pch_ctl1 = 0;
858 	if (panel->backlight.active_low_pwm)
859 		pch_ctl1 |= BLM_PCH_POLARITY;
860 
861 	/* After LPT, override is the default. */
862 	if (HAS_PCH_LPT(dev_priv))
863 		pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
864 
865 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
866 	POSTING_READ(BLC_PWM_PCH_CTL1);
867 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
868 
869 	/* This won't stick until the above enable. */
870 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
871 }
872 
873 static void pch_enable_backlight(struct intel_connector *connector)
874 {
875 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
876 	struct intel_panel *panel = &connector->panel;
877 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
878 	enum transcoder cpu_transcoder =
879 		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
880 	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
881 
882 	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
883 	if (cpu_ctl2 & BLM_PWM_ENABLE) {
884 		DRM_DEBUG_KMS("cpu backlight already enabled\n");
885 		cpu_ctl2 &= ~BLM_PWM_ENABLE;
886 		I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
887 	}
888 
889 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
890 	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
891 		DRM_DEBUG_KMS("pch backlight already enabled\n");
892 		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
893 		I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
894 	}
895 
896 	if (cpu_transcoder == TRANSCODER_EDP)
897 		cpu_ctl2 = BLM_TRANSCODER_EDP;
898 	else
899 		cpu_ctl2 = BLM_PIPE(cpu_transcoder);
900 	I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
901 	POSTING_READ(BLC_PWM_CPU_CTL2);
902 	I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
903 
904 	/* This won't stick until the above enable. */
905 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
906 
907 	pch_ctl2 = panel->backlight.max << 16;
908 	I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
909 
910 	pch_ctl1 = 0;
911 	if (panel->backlight.active_low_pwm)
912 		pch_ctl1 |= BLM_PCH_POLARITY;
913 
914 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
915 	POSTING_READ(BLC_PWM_PCH_CTL1);
916 	I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
917 }
918 
919 static void i9xx_enable_backlight(struct intel_connector *connector)
920 {
921 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
922 	struct intel_panel *panel = &connector->panel;
923 	u32 ctl, freq;
924 
925 	ctl = I915_READ(BLC_PWM_CTL);
926 	if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
927 		DRM_DEBUG_KMS("backlight already enabled\n");
928 		I915_WRITE(BLC_PWM_CTL, 0);
929 	}
930 
931 	freq = panel->backlight.max;
932 	if (panel->backlight.combination_mode)
933 		freq /= 0xff;
934 
935 	ctl = freq << 17;
936 	if (panel->backlight.combination_mode)
937 		ctl |= BLM_LEGACY_MODE;
938 	if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
939 		ctl |= BLM_POLARITY_PNV;
940 
941 	I915_WRITE(BLC_PWM_CTL, ctl);
942 	POSTING_READ(BLC_PWM_CTL);
943 
944 	/* XXX: combine this into above write? */
945 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
946 
947 	/*
948 	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
949 	 * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
950 	 * that has backlight.
951 	 */
952 	if (IS_GEN2(dev_priv))
953 		I915_WRITE(BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
954 }
955 
956 static void i965_enable_backlight(struct intel_connector *connector)
957 {
958 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
959 	struct intel_panel *panel = &connector->panel;
960 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
961 	u32 ctl, ctl2, freq;
962 
963 	ctl2 = I915_READ(BLC_PWM_CTL2);
964 	if (ctl2 & BLM_PWM_ENABLE) {
965 		DRM_DEBUG_KMS("backlight already enabled\n");
966 		ctl2 &= ~BLM_PWM_ENABLE;
967 		I915_WRITE(BLC_PWM_CTL2, ctl2);
968 	}
969 
970 	freq = panel->backlight.max;
971 	if (panel->backlight.combination_mode)
972 		freq /= 0xff;
973 
974 	ctl = freq << 16;
975 	I915_WRITE(BLC_PWM_CTL, ctl);
976 
977 	ctl2 = BLM_PIPE(pipe);
978 	if (panel->backlight.combination_mode)
979 		ctl2 |= BLM_COMBINATION_MODE;
980 	if (panel->backlight.active_low_pwm)
981 		ctl2 |= BLM_POLARITY_I965;
982 	I915_WRITE(BLC_PWM_CTL2, ctl2);
983 	POSTING_READ(BLC_PWM_CTL2);
984 	I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
985 
986 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
987 }
988 
989 static void vlv_enable_backlight(struct intel_connector *connector)
990 {
991 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
992 	struct intel_panel *panel = &connector->panel;
993 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
994 	u32 ctl, ctl2;
995 
996 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
997 		return;
998 
999 	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
1000 	if (ctl2 & BLM_PWM_ENABLE) {
1001 		DRM_DEBUG_KMS("backlight already enabled\n");
1002 		ctl2 &= ~BLM_PWM_ENABLE;
1003 		I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
1004 	}
1005 
1006 	ctl = panel->backlight.max << 16;
1007 	I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
1008 
1009 	/* XXX: combine this into above write? */
1010 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
1011 
1012 	ctl2 = 0;
1013 	if (panel->backlight.active_low_pwm)
1014 		ctl2 |= BLM_POLARITY_I965;
1015 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
1016 	POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
1017 	I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
1018 }
1019 
1020 static void bxt_enable_backlight(struct intel_connector *connector)
1021 {
1022 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1023 	struct intel_panel *panel = &connector->panel;
1024 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
1025 	u32 pwm_ctl, val;
1026 
1027 	/* To use 2nd set of backlight registers, utility pin has to be
1028 	 * enabled with PWM mode.
1029 	 * The field should only be changed when the utility pin is disabled
1030 	 */
1031 	if (panel->backlight.controller == 1) {
1032 		val = I915_READ(UTIL_PIN_CTL);
1033 		if (val & UTIL_PIN_ENABLE) {
1034 			DRM_DEBUG_KMS("util pin already enabled\n");
1035 			val &= ~UTIL_PIN_ENABLE;
1036 			I915_WRITE(UTIL_PIN_CTL, val);
1037 		}
1038 
1039 		val = 0;
1040 		if (panel->backlight.util_pin_active_low)
1041 			val |= UTIL_PIN_POLARITY;
1042 		I915_WRITE(UTIL_PIN_CTL, val | UTIL_PIN_PIPE(pipe) |
1043 				UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
1044 	}
1045 
1046 	pwm_ctl = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
1047 	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
1048 		DRM_DEBUG_KMS("backlight already enabled\n");
1049 		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
1050 		I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
1051 				pwm_ctl);
1052 	}
1053 
1054 	I915_WRITE(BXT_BLC_PWM_FREQ(panel->backlight.controller),
1055 			panel->backlight.max);
1056 
1057 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
1058 
1059 	pwm_ctl = 0;
1060 	if (panel->backlight.active_low_pwm)
1061 		pwm_ctl |= BXT_BLC_PWM_POLARITY;
1062 
1063 	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller), pwm_ctl);
1064 	POSTING_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
1065 	I915_WRITE(BXT_BLC_PWM_CTL(panel->backlight.controller),
1066 			pwm_ctl | BXT_BLC_PWM_ENABLE);
1067 }
1068 
1069 static void pwm_enable_backlight(struct intel_connector *connector)
1070 {
1071 	struct intel_panel *panel = &connector->panel;
1072 
1073 	pwm_enable(panel->backlight.pwm);
1074 	intel_panel_actually_set_backlight(connector, panel->backlight.level);
1075 }
1076 
1077 void intel_panel_enable_backlight(struct intel_connector *connector)
1078 {
1079 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1080 	struct intel_panel *panel = &connector->panel;
1081 	enum i915_pipe pipe = intel_get_pipe_from_connector(connector);
1082 
1083 	if (!panel->backlight.present)
1084 		return;
1085 
1086 	DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
1087 
1088 	mutex_lock(&dev_priv->backlight_lock);
1089 
1090 	WARN_ON(panel->backlight.max == 0);
1091 
1092 	if (panel->backlight.level <= panel->backlight.min) {
1093 		panel->backlight.level = panel->backlight.max;
1094 		if (panel->backlight.device)
1095 			panel->backlight.device->props.brightness =
1096 				scale_hw_to_user(connector,
1097 						 panel->backlight.level,
1098 						 panel->backlight.device->props.max_brightness);
1099 	}
1100 
1101 	panel->backlight.enable(connector);
1102 	panel->backlight.enabled = true;
1103 	if (panel->backlight.device)
1104 		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
1105 
1106 	mutex_unlock(&dev_priv->backlight_lock);
1107 }
1108 
1109 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
1110 static int intel_backlight_device_update_status(struct backlight_device *bd)
1111 {
1112 #if 0
1113 	struct intel_connector *connector = bl_get_data(bd);
1114 	struct intel_panel *panel = &connector->panel;
1115 	struct drm_device *dev = connector->base.dev;
1116 
1117 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1118 	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
1119 		      bd->props.brightness, bd->props.max_brightness);
1120 	intel_panel_set_backlight(connector, bd->props.brightness,
1121 				  bd->props.max_brightness);
1122 
1123 	/*
1124 	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
1125 	 * backlight class device does not make it easy to to differentiate
1126 	 * between callbacks for brightness and bl_power, so our backlight_power
1127 	 * callback needs to take this into account.
1128 	 */
1129 	if (panel->backlight.enabled) {
1130 		if (panel->backlight.power) {
1131 			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
1132 				bd->props.brightness != 0;
1133 			panel->backlight.power(connector, enable);
1134 		}
1135 	} else {
1136 		bd->props.power = FB_BLANK_POWERDOWN;
1137 	}
1138 
1139 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1140 #endif
1141 	return 0;
1142 }
1143 
1144 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
1145 {
1146 #if 0
1147 	struct intel_connector *connector = bl_get_data(bd);
1148 	struct drm_device *dev = connector->base.dev;
1149 	struct drm_i915_private *dev_priv = dev->dev_private;
1150 	u32 hw_level;
1151 	int ret;
1152 
1153 	intel_runtime_pm_get(dev_priv);
1154 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1155 
1156 	hw_level = intel_panel_get_backlight(connector);
1157 	ret = scale_hw_to_user(connector, hw_level, bd->props.max_brightness);
1158 
1159 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1160 	intel_runtime_pm_put(dev_priv);
1161 
1162 	return ret;
1163 #endif
1164 	return 0;
1165 }
1166 
1167 static const struct backlight_ops intel_backlight_device_ops = {
1168 	.update_status = intel_backlight_device_update_status,
1169 	.get_brightness = intel_backlight_device_get_brightness,
1170 };
1171 
1172 static int intel_backlight_device_register(struct intel_connector *connector)
1173 {
1174 	struct intel_panel *panel = &connector->panel;
1175 	struct backlight_properties props;
1176 
1177 	if (WARN_ON(panel->backlight.device))
1178 		return -ENODEV;
1179 
1180 	if (!panel->backlight.present)
1181 		return 0;
1182 
1183 	WARN_ON(panel->backlight.max == 0);
1184 
1185 	memset(&props, 0, sizeof(props));
1186 	props.type = BACKLIGHT_RAW;
1187 
1188 	/*
1189 	 * Note: Everything should work even if the backlight device max
1190 	 * presented to the userspace is arbitrarily chosen.
1191 	 */
1192 	props.max_brightness = panel->backlight.max;
1193 	props.brightness = scale_hw_to_user(connector,
1194 					    panel->backlight.level,
1195 					    props.max_brightness);
1196 
1197 	if (panel->backlight.enabled)
1198 		props.power = FB_BLANK_UNBLANK;
1199 	else
1200 		props.power = FB_BLANK_POWERDOWN;
1201 
1202 	/*
1203 	 * Note: using the same name independent of the connector prevents
1204 	 * registration of multiple backlight devices in the driver.
1205 	 */
1206 #if 0
1207 	panel->backlight.device =
1208 		backlight_device_register("intel_backlight",
1209 					  connector->base.kdev,
1210 					  connector,
1211 					  &intel_backlight_device_ops, &props);
1212 
1213 	if (IS_ERR(panel->backlight.device)) {
1214 		DRM_ERROR("Failed to register backlight: %ld\n",
1215 			  PTR_ERR(panel->backlight.device));
1216 		panel->backlight.device = NULL;
1217 		return -ENODEV;
1218 	}
1219 
1220 	DRM_DEBUG_KMS("Connector %s backlight sysfs interface registered\n",
1221 		      connector->base.name);
1222 #endif
1223 
1224 	return 0;
1225 }
1226 
1227 static void intel_backlight_device_unregister(struct intel_connector *connector)
1228 {
1229 #if 0
1230 	struct intel_panel *panel = &connector->panel;
1231 
1232 	if (panel->backlight.device) {
1233 		backlight_device_unregister(panel->backlight.device);
1234 		panel->backlight.device = NULL;
1235 	}
1236 #endif
1237 }
1238 #else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1239 static int intel_backlight_device_register(struct intel_connector *connector)
1240 {
1241 	return 0;
1242 }
1243 static void intel_backlight_device_unregister(struct intel_connector *connector)
1244 {
1245 }
1246 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1247 
1248 /*
1249  * BXT: PWM clock frequency = 19.2 MHz.
1250  */
1251 static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1252 {
1253 	return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
1254 }
1255 
1256 /*
1257  * SPT: This value represents the period of the PWM stream in clock periods
1258  * multiplied by 16 (default increment) or 128 (alternate increment selected in
1259  * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
1260  */
1261 static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1262 {
1263 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1264 	u32 mul;
1265 
1266 	if (I915_READ(SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY)
1267 		mul = 128;
1268 	else
1269 		mul = 16;
1270 
1271 	return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
1272 }
1273 
1274 /*
1275  * LPT: This value represents the period of the PWM stream in clock periods
1276  * multiplied by 128 (default increment) or 16 (alternate increment, selected in
1277  * LPT SOUTH_CHICKEN2 register bit 5).
1278  */
1279 static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1280 {
1281 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1282 	u32 mul, clock;
1283 
1284 	if (I915_READ(SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY)
1285 		mul = 16;
1286 	else
1287 		mul = 128;
1288 
1289 	if (HAS_PCH_LPT_H(dev_priv))
1290 		clock = MHz(135); /* LPT:H */
1291 	else
1292 		clock = MHz(24); /* LPT:LP */
1293 
1294 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1295 }
1296 
1297 /*
1298  * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
1299  * display raw clocks multiplied by 128.
1300  */
1301 static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1302 {
1303 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1304 
1305 	return DIV_ROUND_CLOSEST(KHz(dev_priv->rawclk_freq), pwm_freq_hz * 128);
1306 }
1307 
1308 /*
1309  * Gen2: This field determines the number of time base events (display core
1310  * clock frequency/32) in total for a complete cycle of modulated backlight
1311  * control.
1312  *
1313  * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
1314  * divided by 32.
1315  */
1316 static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1317 {
1318 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1319 	int clock;
1320 
1321 	if (IS_PINEVIEW(dev_priv))
1322 		clock = KHz(dev_priv->rawclk_freq);
1323 	else
1324 		clock = KHz(dev_priv->cdclk_freq);
1325 
1326 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
1327 }
1328 
1329 /*
1330  * Gen4: This value represents the period of the PWM stream in display core
1331  * clocks ([DevCTG] HRAW clocks) multiplied by 128.
1332  *
1333  */
1334 static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1335 {
1336 	struct drm_device *dev = connector->base.dev;
1337 	struct drm_i915_private *dev_priv = dev->dev_private;
1338 	int clock;
1339 
1340 	if (IS_G4X(dev_priv))
1341 		clock = KHz(dev_priv->rawclk_freq);
1342 	else
1343 		clock = KHz(dev_priv->cdclk_freq);
1344 
1345 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
1346 }
1347 
1348 /*
1349  * VLV: This value represents the period of the PWM stream in display core
1350  * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
1351  * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
1352  */
1353 static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1354 {
1355 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1356 	int mul, clock;
1357 
1358 	if ((I915_READ(CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
1359 		if (IS_CHERRYVIEW(dev_priv))
1360 			clock = KHz(19200);
1361 		else
1362 			clock = MHz(25);
1363 		mul = 16;
1364 	} else {
1365 		clock = KHz(dev_priv->rawclk_freq);
1366 		mul = 128;
1367 	}
1368 
1369 	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1370 }
1371 
1372 static u32 get_backlight_max_vbt(struct intel_connector *connector)
1373 {
1374 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1375 	struct intel_panel *panel = &connector->panel;
1376 	u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
1377 	u32 pwm;
1378 
1379 	if (!panel->backlight.hz_to_pwm) {
1380 		DRM_DEBUG_KMS("backlight frequency conversion not supported\n");
1381 		return 0;
1382 	}
1383 
1384 	if (pwm_freq_hz) {
1385 		DRM_DEBUG_KMS("VBT defined backlight frequency %u Hz\n",
1386 			      pwm_freq_hz);
1387 	} else {
1388 		pwm_freq_hz = 200;
1389 		DRM_DEBUG_KMS("default backlight frequency %u Hz\n",
1390 			      pwm_freq_hz);
1391 	}
1392 
1393 	pwm = panel->backlight.hz_to_pwm(connector, pwm_freq_hz);
1394 	if (!pwm) {
1395 		DRM_DEBUG_KMS("backlight frequency conversion failed\n");
1396 		return 0;
1397 	}
1398 
1399 	return pwm;
1400 }
1401 
1402 /*
1403  * Note: The setup hooks can't assume pipe is set!
1404  */
1405 static u32 get_backlight_min_vbt(struct intel_connector *connector)
1406 {
1407 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1408 	struct intel_panel *panel = &connector->panel;
1409 	int min;
1410 
1411 	WARN_ON(panel->backlight.max == 0);
1412 
1413 	/*
1414 	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
1415 	 * to problems. There are such machines out there. Either our
1416 	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1417 	 * against this by letting the minimum be at most (arbitrarily chosen)
1418 	 * 25% of the max.
1419 	 */
1420 	min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
1421 	if (min != dev_priv->vbt.backlight.min_brightness) {
1422 		DRM_DEBUG_KMS("clamping VBT min backlight %d/255 to %d/255\n",
1423 			      dev_priv->vbt.backlight.min_brightness, min);
1424 	}
1425 
1426 	/* vbt value is a coefficient in range [0..255] */
1427 	return scale(min, 0, 255, 0, panel->backlight.max);
1428 }
1429 
1430 static int lpt_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1431 {
1432 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1433 	struct intel_panel *panel = &connector->panel;
1434 	u32 pch_ctl1, pch_ctl2, val;
1435 
1436 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1437 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1438 
1439 	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1440 	panel->backlight.max = pch_ctl2 >> 16;
1441 
1442 	if (!panel->backlight.max)
1443 		panel->backlight.max = get_backlight_max_vbt(connector);
1444 
1445 	if (!panel->backlight.max)
1446 		return -ENODEV;
1447 
1448 	panel->backlight.min = get_backlight_min_vbt(connector);
1449 
1450 	val = lpt_get_backlight(connector);
1451 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1452 
1453 	panel->backlight.enabled = (pch_ctl1 & BLM_PCH_PWM_ENABLE) &&
1454 		panel->backlight.level != 0;
1455 
1456 	return 0;
1457 }
1458 
1459 static int pch_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1460 {
1461 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1462 	struct intel_panel *panel = &connector->panel;
1463 	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1464 
1465 	pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1466 	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1467 
1468 	pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1469 	panel->backlight.max = pch_ctl2 >> 16;
1470 
1471 	if (!panel->backlight.max)
1472 		panel->backlight.max = get_backlight_max_vbt(connector);
1473 
1474 	if (!panel->backlight.max)
1475 		return -ENODEV;
1476 
1477 	panel->backlight.min = get_backlight_min_vbt(connector);
1478 
1479 	val = pch_get_backlight(connector);
1480 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1481 
1482 	cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
1483 	panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1484 		(pch_ctl1 & BLM_PCH_PWM_ENABLE) && panel->backlight.level != 0;
1485 
1486 	return 0;
1487 }
1488 
1489 static int i9xx_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1490 {
1491 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1492 	struct intel_panel *panel = &connector->panel;
1493 	u32 ctl, val;
1494 
1495 	ctl = I915_READ(BLC_PWM_CTL);
1496 
1497 	if (IS_GEN2(dev_priv) || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
1498 		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1499 
1500 	if (IS_PINEVIEW(dev_priv))
1501 		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1502 
1503 	panel->backlight.max = ctl >> 17;
1504 
1505 	if (!panel->backlight.max) {
1506 		panel->backlight.max = get_backlight_max_vbt(connector);
1507 		panel->backlight.max >>= 1;
1508 	}
1509 
1510 	if (!panel->backlight.max)
1511 		return -ENODEV;
1512 
1513 	if (panel->backlight.combination_mode)
1514 		panel->backlight.max *= 0xff;
1515 
1516 	panel->backlight.min = get_backlight_min_vbt(connector);
1517 
1518 	val = i9xx_get_backlight(connector);
1519 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1520 
1521 	panel->backlight.enabled = panel->backlight.level != 0;
1522 
1523 	return 0;
1524 }
1525 
1526 static int i965_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1527 {
1528 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1529 	struct intel_panel *panel = &connector->panel;
1530 	u32 ctl, ctl2, val;
1531 
1532 	ctl2 = I915_READ(BLC_PWM_CTL2);
1533 	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1534 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1535 
1536 	ctl = I915_READ(BLC_PWM_CTL);
1537 	panel->backlight.max = ctl >> 16;
1538 
1539 	if (!panel->backlight.max)
1540 		panel->backlight.max = get_backlight_max_vbt(connector);
1541 
1542 	if (!panel->backlight.max)
1543 		return -ENODEV;
1544 
1545 	if (panel->backlight.combination_mode)
1546 		panel->backlight.max *= 0xff;
1547 
1548 	panel->backlight.min = get_backlight_min_vbt(connector);
1549 
1550 	val = i9xx_get_backlight(connector);
1551 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1552 
1553 	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1554 		panel->backlight.level != 0;
1555 
1556 	return 0;
1557 }
1558 
1559 static int vlv_setup_backlight(struct intel_connector *connector, enum i915_pipe pipe)
1560 {
1561 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1562 	struct intel_panel *panel = &connector->panel;
1563 	u32 ctl, ctl2, val;
1564 
1565 	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
1566 		return -ENODEV;
1567 
1568 	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
1569 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1570 
1571 	ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
1572 	panel->backlight.max = ctl >> 16;
1573 
1574 	if (!panel->backlight.max)
1575 		panel->backlight.max = get_backlight_max_vbt(connector);
1576 
1577 	if (!panel->backlight.max)
1578 		return -ENODEV;
1579 
1580 	panel->backlight.min = get_backlight_min_vbt(connector);
1581 
1582 	val = _vlv_get_backlight(dev_priv, pipe);
1583 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1584 
1585 	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1586 		panel->backlight.level != 0;
1587 
1588 	return 0;
1589 }
1590 
1591 #ifdef __DragonFly__
1592 /*
1593  * Read max backlight level
1594  */
1595 static int
1596 sysctl_backlight_max(SYSCTL_HANDLER_ARGS)
1597 {
1598 	int err, val;
1599 	struct intel_connector *connector = arg1;
1600 	struct drm_device *dev = connector->base.dev;
1601 	struct drm_i915_private *dev_priv = dev->dev_private;
1602 	struct intel_panel *panel = &connector->panel;
1603 
1604 	mutex_lock(&dev_priv->backlight_lock);
1605 	val = panel->backlight.max;
1606 	mutex_unlock(&dev_priv->backlight_lock);
1607 
1608 	err = sysctl_handle_int(oidp, &val, 0, req);
1609 	return(err);
1610 }
1611 
1612 /*
1613  * Read/write backlight level
1614  */
1615 static int
1616 sysctl_backlight_handler(SYSCTL_HANDLER_ARGS)
1617 {
1618 	struct intel_connector *connector = arg1;
1619 	struct drm_device *dev = connector->base.dev;
1620 	struct drm_i915_private *dev_priv = dev->dev_private;
1621 	struct intel_panel *panel = &connector->panel;
1622 	int err, val;
1623 	u32 user_level, max_brightness;
1624 
1625 	mutex_lock(&dev_priv->backlight_lock);
1626 	max_brightness = panel->backlight.max;
1627 	user_level = scale_hw_to_user(connector, panel->backlight.level,
1628 	    max_brightness);
1629 	mutex_unlock(&dev_priv->backlight_lock);
1630 
1631 	val = user_level;
1632 	err = sysctl_handle_int(oidp, &val, 0, req);
1633 	if (err != 0 || req->newptr == NULL) {
1634 		return(err);
1635 	}
1636 
1637 	if (val != user_level && val >= 0 && val <= max_brightness) {
1638 		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1639 		intel_panel_set_backlight(arg1, val, max_brightness);
1640 		drm_modeset_unlock(&dev->mode_config.connection_mutex);
1641 	}
1642 
1643 	return(err);
1644 }
1645 #endif /* __DragonFly__ */
1646 
1647 static int
1648 bxt_setup_backlight(struct intel_connector *connector, enum i915_pipe unused)
1649 {
1650 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1651 	struct intel_panel *panel = &connector->panel;
1652 	u32 pwm_ctl, val;
1653 
1654 	/*
1655 	 * For BXT hard coding the Backlight controller to 0.
1656 	 * TODO : Read the controller value from VBT and generalize
1657 	 */
1658 	panel->backlight.controller = 0;
1659 
1660 	pwm_ctl = I915_READ(BXT_BLC_PWM_CTL(panel->backlight.controller));
1661 
1662 	/* Keeping the check if controller 1 is to be programmed.
1663 	 * This will come into affect once the VBT parsing
1664 	 * is fixed for controller selection, and controller 1 is used
1665 	 * for a prticular display configuration.
1666 	 */
1667 	if (panel->backlight.controller == 1) {
1668 		val = I915_READ(UTIL_PIN_CTL);
1669 		panel->backlight.util_pin_active_low =
1670 					val & UTIL_PIN_POLARITY;
1671 	}
1672 
1673 	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1674 	panel->backlight.max =
1675 		I915_READ(BXT_BLC_PWM_FREQ(panel->backlight.controller));
1676 
1677 	if (!panel->backlight.max)
1678 		panel->backlight.max = get_backlight_max_vbt(connector);
1679 
1680 	if (!panel->backlight.max)
1681 		return -ENODEV;
1682 
1683 	val = bxt_get_backlight(connector);
1684 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
1685 
1686 	panel->backlight.enabled = (pwm_ctl & BXT_BLC_PWM_ENABLE) &&
1687 		panel->backlight.level != 0;
1688 
1689 	return 0;
1690 }
1691 
1692 static int pwm_setup_backlight(struct intel_connector *connector,
1693 			       enum i915_pipe pipe)
1694 {
1695 	struct drm_device *dev = connector->base.dev;
1696 	struct intel_panel *panel = &connector->panel;
1697 	int retval;
1698 
1699 	/* Get the PWM chip for backlight control */
1700 	panel->backlight.pwm = pwm_get(dev->dev, "pwm_backlight");
1701 	if (IS_ERR(panel->backlight.pwm)) {
1702 		DRM_ERROR("Failed to own the pwm chip\n");
1703 		panel->backlight.pwm = NULL;
1704 		return -ENODEV;
1705 	}
1706 
1707 	/*
1708 	 * FIXME: pwm_apply_args() should be removed when switching to
1709 	 * the atomic PWM API.
1710 	 */
1711 #if 0
1712 	pwm_apply_args(panel->backlight.pwm);
1713 #endif
1714 
1715 	retval = pwm_config(panel->backlight.pwm, CRC_PMIC_PWM_PERIOD_NS,
1716 			    CRC_PMIC_PWM_PERIOD_NS);
1717 	if (retval < 0) {
1718 		DRM_ERROR("Failed to configure the pwm chip\n");
1719 		pwm_put(panel->backlight.pwm);
1720 		panel->backlight.pwm = NULL;
1721 		return retval;
1722 	}
1723 
1724 	panel->backlight.min = 0; /* 0% */
1725 	panel->backlight.max = 100; /* 100% */
1726 	panel->backlight.level = DIV_ROUND_UP(
1727 				 pwm_get_duty_cycle(panel->backlight.pwm) * 100,
1728 				 CRC_PMIC_PWM_PERIOD_NS);
1729 	panel->backlight.enabled = panel->backlight.level != 0;
1730 
1731 	return 0;
1732 }
1733 
1734 int intel_panel_setup_backlight(struct drm_connector *connector, enum i915_pipe pipe)
1735 {
1736 	struct drm_i915_private *dev_priv = to_i915(connector->dev);
1737 	struct intel_connector *intel_connector = to_intel_connector(connector);
1738 	struct intel_panel *panel = &intel_connector->panel;
1739 	int ret;
1740 
1741 	if (!dev_priv->vbt.backlight.present) {
1742 		if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
1743 			DRM_DEBUG_KMS("no backlight present per VBT, but present per quirk\n");
1744 		} else {
1745 			DRM_DEBUG_KMS("no backlight present per VBT\n");
1746 			return 0;
1747 		}
1748 	}
1749 
1750 	/* ensure intel_panel has been initialized first */
1751 	if (WARN_ON(!panel->backlight.setup))
1752 		return -ENODEV;
1753 
1754 	/* set level and max in panel struct */
1755 	mutex_lock(&dev_priv->backlight_lock);
1756 	ret = panel->backlight.setup(intel_connector, pipe);
1757 	mutex_unlock(&dev_priv->backlight_lock);
1758 
1759 	if (ret) {
1760 		DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
1761 			      connector->name);
1762 		return ret;
1763 	}
1764 
1765 	panel->backlight.present = true;
1766 
1767 #ifdef __DragonFly__
1768 	SYSCTL_ADD_PROC(&connector->dev->sysctl->ctx, &sysctl__hw_children,
1769 			OID_AUTO, "backlight_max",
1770 			CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_ANYBODY,
1771 			connector, sizeof(int),
1772 			sysctl_backlight_max,
1773 			"I", "Max backlight level");
1774 	SYSCTL_ADD_PROC(&connector->dev->sysctl->ctx, &sysctl__hw_children,
1775 			OID_AUTO, "backlight_level",
1776 			CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY,
1777 			connector, sizeof(int),
1778 			sysctl_backlight_handler,
1779 			"I", "Backlight level");
1780 #endif
1781 
1782 	DRM_DEBUG_KMS("Connector %s backlight initialized, %s, brightness %u/%u\n",
1783 		      connector->name,
1784 		      panel->backlight.enabled ? "enabled" : "disabled",
1785 		      panel->backlight.level, panel->backlight.max);
1786 
1787 	return 0;
1788 }
1789 
1790 void intel_panel_destroy_backlight(struct drm_connector *connector)
1791 {
1792 	struct intel_connector *intel_connector = to_intel_connector(connector);
1793 	struct intel_panel *panel = &intel_connector->panel;
1794 
1795 	/* dispose of the pwm */
1796 	if (panel->backlight.pwm)
1797 		pwm_put(panel->backlight.pwm);
1798 
1799 	panel->backlight.present = false;
1800 }
1801 
1802 /* Set up chip specific backlight functions */
1803 static void
1804 intel_panel_init_backlight_funcs(struct intel_panel *panel)
1805 {
1806 	struct intel_connector *connector =
1807 		container_of(panel, struct intel_connector, panel);
1808 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1809 
1810 	if (IS_BROXTON(dev_priv)) {
1811 		panel->backlight.setup = bxt_setup_backlight;
1812 		panel->backlight.enable = bxt_enable_backlight;
1813 		panel->backlight.disable = bxt_disable_backlight;
1814 		panel->backlight.set = bxt_set_backlight;
1815 		panel->backlight.get = bxt_get_backlight;
1816 		panel->backlight.hz_to_pwm = bxt_hz_to_pwm;
1817 	} else if (HAS_PCH_LPT(dev_priv) || HAS_PCH_SPT(dev_priv) ||
1818 		   HAS_PCH_KBP(dev_priv)) {
1819 		panel->backlight.setup = lpt_setup_backlight;
1820 		panel->backlight.enable = lpt_enable_backlight;
1821 		panel->backlight.disable = lpt_disable_backlight;
1822 		panel->backlight.set = lpt_set_backlight;
1823 		panel->backlight.get = lpt_get_backlight;
1824 		if (HAS_PCH_LPT(dev_priv))
1825 			panel->backlight.hz_to_pwm = lpt_hz_to_pwm;
1826 		else
1827 			panel->backlight.hz_to_pwm = spt_hz_to_pwm;
1828 	} else if (HAS_PCH_SPLIT(dev_priv)) {
1829 		panel->backlight.setup = pch_setup_backlight;
1830 		panel->backlight.enable = pch_enable_backlight;
1831 		panel->backlight.disable = pch_disable_backlight;
1832 		panel->backlight.set = pch_set_backlight;
1833 		panel->backlight.get = pch_get_backlight;
1834 		panel->backlight.hz_to_pwm = pch_hz_to_pwm;
1835 	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
1836 		if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
1837 			panel->backlight.setup = pwm_setup_backlight;
1838 			panel->backlight.enable = pwm_enable_backlight;
1839 			panel->backlight.disable = pwm_disable_backlight;
1840 			panel->backlight.set = pwm_set_backlight;
1841 			panel->backlight.get = pwm_get_backlight;
1842 		} else {
1843 			panel->backlight.setup = vlv_setup_backlight;
1844 			panel->backlight.enable = vlv_enable_backlight;
1845 			panel->backlight.disable = vlv_disable_backlight;
1846 			panel->backlight.set = vlv_set_backlight;
1847 			panel->backlight.get = vlv_get_backlight;
1848 			panel->backlight.hz_to_pwm = vlv_hz_to_pwm;
1849 		}
1850 	} else if (IS_GEN4(dev_priv)) {
1851 		panel->backlight.setup = i965_setup_backlight;
1852 		panel->backlight.enable = i965_enable_backlight;
1853 		panel->backlight.disable = i965_disable_backlight;
1854 		panel->backlight.set = i9xx_set_backlight;
1855 		panel->backlight.get = i9xx_get_backlight;
1856 		panel->backlight.hz_to_pwm = i965_hz_to_pwm;
1857 	} else {
1858 		panel->backlight.setup = i9xx_setup_backlight;
1859 		panel->backlight.enable = i9xx_enable_backlight;
1860 		panel->backlight.disable = i9xx_disable_backlight;
1861 		panel->backlight.set = i9xx_set_backlight;
1862 		panel->backlight.get = i9xx_get_backlight;
1863 		panel->backlight.hz_to_pwm = i9xx_hz_to_pwm;
1864 	}
1865 }
1866 
1867 int intel_panel_init(struct intel_panel *panel,
1868 		     struct drm_display_mode *fixed_mode,
1869 		     struct drm_display_mode *downclock_mode)
1870 {
1871 	intel_panel_init_backlight_funcs(panel);
1872 
1873 	panel->fixed_mode = fixed_mode;
1874 	panel->downclock_mode = downclock_mode;
1875 
1876 	return 0;
1877 }
1878 
1879 void intel_panel_fini(struct intel_panel *panel)
1880 {
1881 	struct intel_connector *intel_connector =
1882 		container_of(panel, struct intel_connector, panel);
1883 
1884 	if (panel->fixed_mode)
1885 		drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
1886 
1887 	if (panel->downclock_mode)
1888 		drm_mode_destroy(intel_connector->base.dev,
1889 				panel->downclock_mode);
1890 }
1891 
1892 void intel_backlight_register(struct drm_device *dev)
1893 {
1894 	struct intel_connector *connector;
1895 
1896 	for_each_intel_connector(dev, connector)
1897 		intel_backlight_device_register(connector);
1898 }
1899 
1900 void intel_backlight_unregister(struct drm_device *dev)
1901 {
1902 	struct intel_connector *connector;
1903 
1904 	for_each_intel_connector(dev, connector)
1905 		intel_backlight_device_unregister(connector);
1906 }
1907