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
44static struct ida bl_ida;
45#define BL_NAME_SIZE 15 // 12 for name + 2 for digits + 1 for '\0'
46
47static bool
48nouveau_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
63static int
64nv40_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
75static int
76nv40_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
90static 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
96static int
97nv40_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 */
116static int
117nv50_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
127retry:
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;
148out:
149	drm_modeset_drop_locks(&ctx);
150	drm_modeset_acquire_fini(&ctx);
151	return ret;
152deadlock:
153	drm_modeset_backoff(&ctx);
154	goto retry;
155}
156
157static int
158nv50_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);
170retry:
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
190out:
191	drm_modeset_drop_locks(&ctx);
192	drm_modeset_acquire_fini(&ctx);
193	return ret;
194deadlock:
195	drm_modeset_backoff(&ctx);
196	goto retry;
197}
198
199static const struct backlight_ops nv50_edp_bl_ops = {
200	.get_brightness = nv50_edp_get_brightness,
201	.update_status = nv50_edp_set_brightness,
202};
203
204static int
205nv50_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
212static int
213nv50_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
220static 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 */
229static int
230nv50_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
289int
290nouveau_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
374fail_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
386void
387nouveau_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
403void
404nouveau_backlight_ctor(void)
405{
406	ida_init(&bl_ida);
407}
408
409void
410nouveau_backlight_dtor(void)
411{
412	ida_destroy(&bl_ida);
413}
414