xref: /linux/drivers/gpu/drm/nouveau/nouveau_backlight.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 /*
2  * Copyright (C) 2009 Red Hat <mjg@redhat.com>
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining
5  * a copy of this software and associated documentation files (the
6  * "Software"), to deal in the Software without restriction, including
7  * without limitation the rights to use, copy, modify, merge, publish,
8  * distribute, sublicense, and/or sell copies of the Software, and to
9  * permit persons to whom the Software is furnished to do so, subject to
10  * the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the
13  * next paragraph) shall be included in all copies or substantial
14  * portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
19  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  *
24  */
25 
26 /*
27  * Authors:
28  *  Matthew Garrett <mjg@redhat.com>
29  *
30  * Register locations derived from NVClock by Roderick Colenbrander
31  */
32 
33 #include <linux/apple-gmux.h>
34 #include <linux/backlight.h>
35 #include <linux/idr.h>
36 #include <drm/drm_probe_helper.h>
37 
38 #include "nouveau_drv.h"
39 #include "nouveau_reg.h"
40 #include "nouveau_encoder.h"
41 #include "nouveau_connector.h"
42 #include "nouveau_acpi.h"
43 
44 static struct ida bl_ida;
45 #define BL_NAME_SIZE 15 // 12 for name + 2 for digits + 1 for '\0'
46 
47 static bool
48 nouveau_get_backlight_name(char backlight_name[BL_NAME_SIZE],
49 			   struct nouveau_backlight *bl)
50 {
51 	const int nb = ida_alloc_max(&bl_ida, 99, GFP_KERNEL);
52 
53 	if (nb < 0)
54 		return false;
55 	if (nb > 0)
56 		snprintf(backlight_name, BL_NAME_SIZE, "nv_backlight%d", nb);
57 	else
58 		snprintf(backlight_name, BL_NAME_SIZE, "nv_backlight");
59 	bl->id = nb;
60 	return true;
61 }
62 
63 static int
64 nv40_get_intensity(struct backlight_device *bd)
65 {
66 	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
67 	struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
68 	struct nvif_object *device = &drm->client.device.object;
69 	int val = (nvif_rd32(device, NV40_PMC_BACKLIGHT) &
70 		   NV40_PMC_BACKLIGHT_MASK) >> 16;
71 
72 	return val;
73 }
74 
75 static int
76 nv40_set_intensity(struct backlight_device *bd)
77 {
78 	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
79 	struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
80 	struct nvif_object *device = &drm->client.device.object;
81 	int val = bd->props.brightness;
82 	int reg = nvif_rd32(device, NV40_PMC_BACKLIGHT);
83 
84 	nvif_wr32(device, NV40_PMC_BACKLIGHT,
85 		  (val << 16) | (reg & ~NV40_PMC_BACKLIGHT_MASK));
86 
87 	return 0;
88 }
89 
90 static const struct backlight_ops nv40_bl_ops = {
91 	.options = BL_CORE_SUSPENDRESUME,
92 	.get_brightness = nv40_get_intensity,
93 	.update_status = nv40_set_intensity,
94 };
95 
96 static int
97 nv40_backlight_init(struct nouveau_encoder *encoder,
98 		    struct backlight_properties *props,
99 		    const struct backlight_ops **ops)
100 {
101 	struct nouveau_drm *drm = nouveau_drm(encoder->base.base.dev);
102 	struct nvif_object *device = &drm->client.device.object;
103 
104 	if (!(nvif_rd32(device, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK))
105 		return -ENODEV;
106 
107 	props->max_brightness = 31;
108 	*ops = &nv40_bl_ops;
109 	return 0;
110 }
111 
112 /*
113  * eDP brightness callbacks need to happen under lock, since we need to
114  * enable/disable the backlight ourselves for modesets
115  */
116 static int
117 nv50_edp_get_brightness(struct backlight_device *bd)
118 {
119 	struct drm_connector *connector = dev_get_drvdata(bd->dev.parent);
120 	struct drm_device *dev = connector->dev;
121 	struct drm_crtc *crtc;
122 	struct drm_modeset_acquire_ctx ctx;
123 	int ret = 0;
124 
125 	drm_modeset_acquire_init(&ctx, 0);
126 
127 retry:
128 	ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
129 	if (ret == -EDEADLK)
130 		goto deadlock;
131 	else if (ret < 0)
132 		goto out;
133 
134 	crtc = connector->state->crtc;
135 	if (!crtc)
136 		goto out;
137 
138 	ret = drm_modeset_lock(&crtc->mutex, &ctx);
139 	if (ret == -EDEADLK)
140 		goto deadlock;
141 	else if (ret < 0)
142 		goto out;
143 
144 	if (!crtc->state->active)
145 		goto out;
146 
147 	ret = bd->props.brightness;
148 out:
149 	drm_modeset_drop_locks(&ctx);
150 	drm_modeset_acquire_fini(&ctx);
151 	return ret;
152 deadlock:
153 	drm_modeset_backoff(&ctx);
154 	goto retry;
155 }
156 
157 static int
158 nv50_edp_set_brightness(struct backlight_device *bd)
159 {
160 	struct drm_connector *connector = dev_get_drvdata(bd->dev.parent);
161 	struct nouveau_connector *nv_connector = nouveau_connector(connector);
162 	struct drm_device *dev = connector->dev;
163 	struct drm_crtc *crtc;
164 	struct drm_dp_aux *aux = &nv_connector->aux;
165 	struct nouveau_backlight *nv_bl = nv_connector->backlight;
166 	struct drm_modeset_acquire_ctx ctx;
167 	int ret = 0;
168 
169 	drm_modeset_acquire_init(&ctx, 0);
170 retry:
171 	ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
172 	if (ret == -EDEADLK)
173 		goto deadlock;
174 	else if (ret < 0)
175 		goto out;
176 
177 	crtc = connector->state->crtc;
178 	if (!crtc)
179 		goto out;
180 
181 	ret = drm_modeset_lock(&crtc->mutex, &ctx);
182 	if (ret == -EDEADLK)
183 		goto deadlock;
184 	else if (ret < 0)
185 		goto out;
186 
187 	if (crtc->state->active)
188 		ret = drm_edp_backlight_set_level(aux, &nv_bl->edp_info, bd->props.brightness);
189 
190 out:
191 	drm_modeset_drop_locks(&ctx);
192 	drm_modeset_acquire_fini(&ctx);
193 	return ret;
194 deadlock:
195 	drm_modeset_backoff(&ctx);
196 	goto retry;
197 }
198 
199 static const struct backlight_ops nv50_edp_bl_ops = {
200 	.get_brightness = nv50_edp_get_brightness,
201 	.update_status = nv50_edp_set_brightness,
202 };
203 
204 static int
205 nv50_get_intensity(struct backlight_device *bd)
206 {
207 	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
208 
209 	return nvif_outp_bl_get(&nv_encoder->outp);
210 }
211 
212 static int
213 nv50_set_intensity(struct backlight_device *bd)
214 {
215 	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
216 
217 	return nvif_outp_bl_set(&nv_encoder->outp, backlight_get_brightness(bd));
218 }
219 
220 static const struct backlight_ops nv50_bl_ops = {
221 	.options = BL_CORE_SUSPENDRESUME,
222 	.get_brightness = nv50_get_intensity,
223 	.update_status = nv50_set_intensity,
224 };
225 
226 /* FIXME: perform backlight probing for eDP _before_ this, this only gets called after connector
227  * registration which happens after the initial modeset
228  */
229 static int
230 nv50_backlight_init(struct nouveau_backlight *bl,
231 		    struct nouveau_connector *nv_conn,
232 		    struct nouveau_encoder *nv_encoder,
233 		    struct backlight_properties *props,
234 		    const struct backlight_ops **ops)
235 {
236 	struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
237 
238 	/*
239 	 * Note when this runs the connectors have not been probed yet,
240 	 * so nv_conn->base.status is not set yet.
241 	 */
242 	if (nvif_outp_bl_get(&nv_encoder->outp) < 0 ||
243 	    drm_helper_probe_detect(&nv_conn->base, NULL, false) != connector_status_connected)
244 		return -ENODEV;
245 
246 	if (nv_conn->type == DCB_CONNECTOR_eDP) {
247 		int ret;
248 		u16 current_level;
249 		u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE];
250 		u8 current_mode;
251 
252 		ret = drm_dp_dpcd_read(&nv_conn->aux, DP_EDP_DPCD_REV, edp_dpcd,
253 				       EDP_DISPLAY_CTL_CAP_SIZE);
254 		if (ret < 0)
255 			return ret;
256 
257 		/* TODO: Add support for hybrid PWM/DPCD panels */
258 		if (drm_edp_backlight_supported(edp_dpcd) &&
259 		    (edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
260 		    (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)) {
261 			NV_DEBUG(drm, "DPCD backlight controls supported on %s\n",
262 				 nv_conn->base.name);
263 
264 			ret = drm_edp_backlight_init(&nv_conn->aux, &bl->edp_info, 0, edp_dpcd,
265 						     &current_level, &current_mode);
266 			if (ret < 0)
267 				return ret;
268 
269 			ret = drm_edp_backlight_enable(&nv_conn->aux, &bl->edp_info, current_level);
270 			if (ret < 0) {
271 				NV_ERROR(drm, "Failed to enable backlight on %s: %d\n",
272 					 nv_conn->base.name, ret);
273 				return ret;
274 			}
275 
276 			*ops = &nv50_edp_bl_ops;
277 			props->brightness = current_level;
278 			props->max_brightness = bl->edp_info.max;
279 			bl->uses_dpcd = true;
280 			return 0;
281 		}
282 	}
283 
284 	*ops = &nv50_bl_ops;
285 	props->max_brightness = 100;
286 	return 0;
287 }
288 
289 int
290 nouveau_backlight_init(struct drm_connector *connector)
291 {
292 	struct nouveau_drm *drm = nouveau_drm(connector->dev);
293 	struct nouveau_backlight *bl;
294 	struct nouveau_encoder *nv_encoder = NULL;
295 	struct nvif_device *device = &drm->client.device;
296 	char backlight_name[BL_NAME_SIZE];
297 	struct backlight_properties props = {0};
298 	const struct backlight_ops *ops;
299 	int ret;
300 
301 	if (apple_gmux_present()) {
302 		NV_INFO_ONCE(drm, "Apple GMUX detected: not registering Nouveau backlight interface\n");
303 		return 0;
304 	}
305 
306 	if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS)
307 		nv_encoder = find_encoder(connector, DCB_OUTPUT_LVDS);
308 	else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP)
309 		nv_encoder = find_encoder(connector, DCB_OUTPUT_DP);
310 	else
311 		return 0;
312 
313 	if (!nv_encoder)
314 		return 0;
315 
316 	bl = kzalloc(sizeof(*bl), GFP_KERNEL);
317 	if (!bl)
318 		return -ENOMEM;
319 
320 	switch (device->info.family) {
321 	case NV_DEVICE_INFO_V0_CURIE:
322 		ret = nv40_backlight_init(nv_encoder, &props, &ops);
323 		break;
324 	case NV_DEVICE_INFO_V0_TESLA:
325 	case NV_DEVICE_INFO_V0_FERMI:
326 	case NV_DEVICE_INFO_V0_KEPLER:
327 	case NV_DEVICE_INFO_V0_MAXWELL:
328 	case NV_DEVICE_INFO_V0_PASCAL:
329 	case NV_DEVICE_INFO_V0_VOLTA:
330 	case NV_DEVICE_INFO_V0_TURING:
331 	case NV_DEVICE_INFO_V0_AMPERE: //XXX: not confirmed
332 		ret = nv50_backlight_init(bl, nouveau_connector(connector),
333 					  nv_encoder, &props, &ops);
334 		break;
335 	default:
336 		ret = 0;
337 		goto fail_alloc;
338 	}
339 
340 	if (ret) {
341 		if (ret == -ENODEV)
342 			ret = 0;
343 		goto fail_alloc;
344 	}
345 
346 	if (!nouveau_acpi_video_backlight_use_native()) {
347 		NV_INFO(drm, "Skipping nv_backlight registration\n");
348 		goto fail_alloc;
349 	}
350 
351 	if (!nouveau_get_backlight_name(backlight_name, bl)) {
352 		NV_ERROR(drm, "Failed to retrieve a unique name for the backlight interface\n");
353 		goto fail_alloc;
354 	}
355 
356 	props.type = BACKLIGHT_RAW;
357 	bl->dev = backlight_device_register(backlight_name, connector->kdev,
358 					    nv_encoder, ops, &props);
359 	if (IS_ERR(bl->dev)) {
360 		if (bl->id >= 0)
361 			ida_free(&bl_ida, bl->id);
362 		ret = PTR_ERR(bl->dev);
363 		goto fail_alloc;
364 	}
365 
366 	nouveau_connector(connector)->backlight = bl;
367 	if (!bl->dev->props.brightness)
368 		bl->dev->props.brightness =
369 			bl->dev->ops->get_brightness(bl->dev);
370 	backlight_update_status(bl->dev);
371 
372 	return 0;
373 
374 fail_alloc:
375 	kfree(bl);
376 	/*
377 	 * If we get here we have an internal panel, but no nv_backlight,
378 	 * try registering an ACPI video backlight device instead.
379 	 */
380 	if (ret == 0)
381 		nouveau_acpi_video_register_backlight();
382 
383 	return ret;
384 }
385 
386 void
387 nouveau_backlight_fini(struct drm_connector *connector)
388 {
389 	struct nouveau_connector *nv_conn = nouveau_connector(connector);
390 	struct nouveau_backlight *bl = nv_conn->backlight;
391 
392 	if (!bl)
393 		return;
394 
395 	if (bl->id >= 0)
396 		ida_free(&bl_ida, bl->id);
397 
398 	backlight_device_unregister(bl->dev);
399 	nv_conn->backlight = NULL;
400 	kfree(bl);
401 }
402 
403 void
404 nouveau_backlight_ctor(void)
405 {
406 	ida_init(&bl_ida);
407 }
408 
409 void
410 nouveau_backlight_dtor(void)
411 {
412 	ida_destroy(&bl_ida);
413 }
414