1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
4 */
5
6#include "dp_panel.h"
7
8#include <drm/drm_connector.h>
9#include <drm/drm_edid.h>
10#include <drm/drm_print.h>
11
12struct dp_panel_private {
13	struct device *dev;
14	struct dp_panel dp_panel;
15	struct drm_dp_aux *aux;
16	struct dp_link *link;
17	struct dp_catalog *catalog;
18	bool panel_on;
19	bool aux_cfg_update_done;
20};
21
22static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
23{
24	int rc = 0;
25	size_t len;
26	ssize_t rlen;
27	struct dp_panel_private *panel;
28	struct dp_link_info *link_info;
29	u8 *dpcd, major = 0, minor = 0, temp;
30	u32 offset = DP_DPCD_REV;
31
32	dpcd = dp_panel->dpcd;
33
34	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
35	link_info = &dp_panel->link_info;
36
37	rlen = drm_dp_dpcd_read(panel->aux, offset,
38			dpcd, (DP_RECEIVER_CAP_SIZE + 1));
39	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
40		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
41		if (rlen == -ETIMEDOUT)
42			rc = rlen;
43		else
44			rc = -EINVAL;
45
46		goto end;
47	}
48
49	temp = dpcd[DP_TRAINING_AUX_RD_INTERVAL];
50
51	/* check for EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT */
52	if (temp & BIT(7)) {
53		DRM_DEBUG_DP("using EXTENDED_RECEIVER_CAPABILITY_FIELD\n");
54		offset = DPRX_EXTENDED_DPCD_FIELD;
55	}
56
57	rlen = drm_dp_dpcd_read(panel->aux, offset,
58		dpcd, (DP_RECEIVER_CAP_SIZE + 1));
59	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
60		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
61		if (rlen == -ETIMEDOUT)
62			rc = rlen;
63		else
64			rc = -EINVAL;
65
66		goto end;
67	}
68
69	link_info->revision = dpcd[DP_DPCD_REV];
70	major = (link_info->revision >> 4) & 0x0f;
71	minor = link_info->revision & 0x0f;
72
73	link_info->rate = drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]);
74	link_info->num_lanes = dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
75
76	if (link_info->num_lanes > dp_panel->max_dp_lanes)
77		link_info->num_lanes = dp_panel->max_dp_lanes;
78
79	/* Limit support upto HBR2 until HBR3 support is added */
80	if (link_info->rate >= (drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4)))
81		link_info->rate = drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4);
82
83	DRM_DEBUG_DP("version: %d.%d\n", major, minor);
84	DRM_DEBUG_DP("link_rate=%d\n", link_info->rate);
85	DRM_DEBUG_DP("lane_count=%d\n", link_info->num_lanes);
86
87	if (drm_dp_enhanced_frame_cap(dpcd))
88		link_info->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
89
90	dp_panel->dfp_present = dpcd[DP_DOWNSTREAMPORT_PRESENT];
91	dp_panel->dfp_present &= DP_DWN_STRM_PORT_PRESENT;
92
93	if (dp_panel->dfp_present && (dpcd[DP_DPCD_REV] > 0x10)) {
94		dp_panel->ds_port_cnt = dpcd[DP_DOWN_STREAM_PORT_COUNT];
95		dp_panel->ds_port_cnt &= DP_PORT_COUNT_MASK;
96		len = DP_DOWNSTREAM_PORTS * DP_DOWNSTREAM_CAP_SIZE;
97
98		rlen = drm_dp_dpcd_read(panel->aux,
99			DP_DOWNSTREAM_PORT_0, dp_panel->ds_cap_info, len);
100		if (rlen < len) {
101			DRM_ERROR("ds port status failed, rlen=%zd\n", rlen);
102			rc = -EINVAL;
103			goto end;
104		}
105	}
106
107end:
108	return rc;
109}
110
111static u32 dp_panel_get_supported_bpp(struct dp_panel *dp_panel,
112		u32 mode_edid_bpp, u32 mode_pclk_khz)
113{
114	struct dp_link_info *link_info;
115	const u32 max_supported_bpp = 30, min_supported_bpp = 18;
116	u32 bpp = 0, data_rate_khz = 0;
117
118	bpp = min_t(u32, mode_edid_bpp, max_supported_bpp);
119
120	link_info = &dp_panel->link_info;
121	data_rate_khz = link_info->num_lanes * link_info->rate * 8;
122
123	while (bpp > min_supported_bpp) {
124		if (mode_pclk_khz * bpp <= data_rate_khz)
125			break;
126		bpp -= 6;
127	}
128
129	return bpp;
130}
131
132static int dp_panel_update_modes(struct drm_connector *connector,
133	struct edid *edid)
134{
135	int rc = 0;
136
137	if (edid) {
138		rc = drm_connector_update_edid_property(connector, edid);
139		if (rc) {
140			DRM_ERROR("failed to update edid property %d\n", rc);
141			return rc;
142		}
143		rc = drm_add_edid_modes(connector, edid);
144		DRM_DEBUG_DP("%s -", __func__);
145		return rc;
146	}
147
148	rc = drm_connector_update_edid_property(connector, NULL);
149	if (rc)
150		DRM_ERROR("failed to update edid property %d\n", rc);
151
152	return rc;
153}
154
155int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
156	struct drm_connector *connector)
157{
158	int rc = 0, bw_code;
159	int rlen, count;
160	struct dp_panel_private *panel;
161
162	if (!dp_panel || !connector) {
163		DRM_ERROR("invalid input\n");
164		return -EINVAL;
165	}
166
167	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
168
169	rc = dp_panel_read_dpcd(dp_panel);
170	bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
171	if (rc || !is_link_rate_valid(bw_code) ||
172			!is_lane_count_valid(dp_panel->link_info.num_lanes) ||
173			(bw_code > dp_panel->max_bw_code)) {
174		DRM_ERROR("read dpcd failed %d\n", rc);
175		return rc;
176	}
177
178	if (dp_panel->dfp_present) {
179		rlen = drm_dp_dpcd_read(panel->aux, DP_SINK_COUNT,
180				&count, 1);
181		if (rlen == 1) {
182			count = DP_GET_SINK_COUNT(count);
183			if (!count) {
184				DRM_ERROR("no downstream ports connected\n");
185				panel->link->sink_count = 0;
186				rc = -ENOTCONN;
187				goto end;
188			}
189		}
190	}
191
192	kfree(dp_panel->edid);
193	dp_panel->edid = NULL;
194
195	dp_panel->edid = drm_get_edid(connector,
196					      &panel->aux->ddc);
197	if (!dp_panel->edid) {
198		DRM_ERROR("panel edid read failed\n");
199		/* check edid read fail is due to unplug */
200		if (!dp_catalog_link_is_connected(panel->catalog)) {
201			rc = -ETIMEDOUT;
202			goto end;
203		}
204
205		/* fail safe edid */
206		mutex_lock(&connector->dev->mode_config.mutex);
207		if (drm_add_modes_noedid(connector, 640, 480))
208			drm_set_preferred_mode(connector, 640, 480);
209		mutex_unlock(&connector->dev->mode_config.mutex);
210	}
211
212	if (panel->aux_cfg_update_done) {
213		DRM_DEBUG_DP("read DPCD with updated AUX config\n");
214		rc = dp_panel_read_dpcd(dp_panel);
215		bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
216		if (rc || !is_link_rate_valid(bw_code) ||
217			!is_lane_count_valid(dp_panel->link_info.num_lanes)
218			|| (bw_code > dp_panel->max_bw_code)) {
219			DRM_ERROR("read dpcd failed %d\n", rc);
220			return rc;
221		}
222		panel->aux_cfg_update_done = false;
223	}
224end:
225	return rc;
226}
227
228u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel,
229		u32 mode_edid_bpp, u32 mode_pclk_khz)
230{
231	struct dp_panel_private *panel;
232	u32 bpp = mode_edid_bpp;
233
234	if (!dp_panel || !mode_edid_bpp || !mode_pclk_khz) {
235		DRM_ERROR("invalid input\n");
236		return 0;
237	}
238
239	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
240
241	if (dp_panel->video_test)
242		bpp = dp_link_bit_depth_to_bpp(
243				panel->link->test_video.test_bit_depth);
244	else
245		bpp = dp_panel_get_supported_bpp(dp_panel, mode_edid_bpp,
246				mode_pclk_khz);
247
248	return bpp;
249}
250
251int dp_panel_get_modes(struct dp_panel *dp_panel,
252	struct drm_connector *connector, struct dp_display_mode *mode)
253{
254	if (!dp_panel) {
255		DRM_ERROR("invalid input\n");
256		return -EINVAL;
257	}
258
259	if (dp_panel->edid)
260		return dp_panel_update_modes(connector, dp_panel->edid);
261
262	return 0;
263}
264
265static u8 dp_panel_get_edid_checksum(struct edid *edid)
266{
267	edid += edid->extensions;
268
269	return edid->checksum;
270}
271
272void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
273{
274	struct dp_panel_private *panel;
275
276	if (!dp_panel) {
277		DRM_ERROR("invalid input\n");
278		return;
279	}
280
281	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
282
283	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
284		u8 checksum;
285
286		if (dp_panel->edid)
287			checksum = dp_panel_get_edid_checksum(dp_panel->edid);
288		else
289			checksum = dp_panel->connector->real_edid_checksum;
290
291		dp_link_send_edid_checksum(panel->link, checksum);
292		dp_link_send_test_response(panel->link);
293	}
294}
295
296void dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)
297{
298	struct dp_catalog *catalog;
299	struct dp_panel_private *panel;
300
301	if (!dp_panel) {
302		DRM_ERROR("invalid input\n");
303		return;
304	}
305
306	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
307	catalog = panel->catalog;
308
309	if (!panel->panel_on) {
310		DRM_DEBUG_DP("DP panel not enabled, handle TPG on next on\n");
311		return;
312	}
313
314	if (!enable) {
315		dp_catalog_panel_tpg_disable(catalog);
316		return;
317	}
318
319	DRM_DEBUG_DP("%s: calling catalog tpg_enable\n", __func__);
320	dp_catalog_panel_tpg_enable(catalog, &panel->dp_panel.dp_mode.drm_mode);
321}
322
323void dp_panel_dump_regs(struct dp_panel *dp_panel)
324{
325	struct dp_catalog *catalog;
326	struct dp_panel_private *panel;
327
328	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
329	catalog = panel->catalog;
330
331	dp_catalog_dump_regs(catalog);
332}
333
334int dp_panel_timing_cfg(struct dp_panel *dp_panel)
335{
336	int rc = 0;
337	u32 data, total_ver, total_hor;
338	struct dp_catalog *catalog;
339	struct dp_panel_private *panel;
340	struct drm_display_mode *drm_mode;
341
342	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
343	catalog = panel->catalog;
344	drm_mode = &panel->dp_panel.dp_mode.drm_mode;
345
346	DRM_DEBUG_DP("width=%d hporch= %d %d %d\n",
347		drm_mode->hdisplay, drm_mode->htotal - drm_mode->hsync_end,
348		drm_mode->hsync_start - drm_mode->hdisplay,
349		drm_mode->hsync_end - drm_mode->hsync_start);
350
351	DRM_DEBUG_DP("height=%d vporch= %d %d %d\n",
352		drm_mode->vdisplay, drm_mode->vtotal - drm_mode->vsync_end,
353		drm_mode->vsync_start - drm_mode->vdisplay,
354		drm_mode->vsync_end - drm_mode->vsync_start);
355
356	total_hor = drm_mode->htotal;
357
358	total_ver = drm_mode->vtotal;
359
360	data = total_ver;
361	data <<= 16;
362	data |= total_hor;
363
364	catalog->total = data;
365
366	data = (drm_mode->vtotal - drm_mode->vsync_start);
367	data <<= 16;
368	data |= (drm_mode->htotal - drm_mode->hsync_start);
369
370	catalog->sync_start = data;
371
372	data = drm_mode->vsync_end - drm_mode->vsync_start;
373	data <<= 16;
374	data |= (panel->dp_panel.dp_mode.v_active_low << 31);
375	data |= drm_mode->hsync_end - drm_mode->hsync_start;
376	data |= (panel->dp_panel.dp_mode.h_active_low << 15);
377
378	catalog->width_blanking = data;
379
380	data = drm_mode->vdisplay;
381	data <<= 16;
382	data |= drm_mode->hdisplay;
383
384	catalog->dp_active = data;
385
386	dp_catalog_panel_timing_cfg(catalog);
387	panel->panel_on = true;
388
389	return rc;
390}
391
392int dp_panel_init_panel_info(struct dp_panel *dp_panel)
393{
394	int rc = 0;
395	struct drm_display_mode *drm_mode;
396
397	drm_mode = &dp_panel->dp_mode.drm_mode;
398
399	/*
400	 * print resolution info as this is a result
401	 * of user initiated action of cable connection
402	 */
403	DRM_DEBUG_DP("SET NEW RESOLUTION:\n");
404	DRM_DEBUG_DP("%dx%d@%dfps\n", drm_mode->hdisplay,
405		drm_mode->vdisplay, drm_mode_vrefresh(drm_mode));
406	DRM_DEBUG_DP("h_porches(back|front|width) = (%d|%d|%d)\n",
407			drm_mode->htotal - drm_mode->hsync_end,
408			drm_mode->hsync_start - drm_mode->hdisplay,
409			drm_mode->hsync_end - drm_mode->hsync_start);
410	DRM_DEBUG_DP("v_porches(back|front|width) = (%d|%d|%d)\n",
411			drm_mode->vtotal - drm_mode->vsync_end,
412			drm_mode->vsync_start - drm_mode->vdisplay,
413			drm_mode->vsync_end - drm_mode->vsync_start);
414	DRM_DEBUG_DP("pixel clock (KHz)=(%d)\n", drm_mode->clock);
415	DRM_DEBUG_DP("bpp = %d\n", dp_panel->dp_mode.bpp);
416
417	dp_panel->dp_mode.bpp = max_t(u32, 18,
418					min_t(u32, dp_panel->dp_mode.bpp, 30));
419	DRM_DEBUG_DP("updated bpp = %d\n", dp_panel->dp_mode.bpp);
420
421	return rc;
422}
423
424struct dp_panel *dp_panel_get(struct dp_panel_in *in)
425{
426	struct dp_panel_private *panel;
427	struct dp_panel *dp_panel;
428
429	if (!in->dev || !in->catalog || !in->aux || !in->link) {
430		DRM_ERROR("invalid input\n");
431		return ERR_PTR(-EINVAL);
432	}
433
434	panel = devm_kzalloc(in->dev, sizeof(*panel), GFP_KERNEL);
435	if (!panel)
436		return ERR_PTR(-ENOMEM);
437
438	panel->dev = in->dev;
439	panel->aux = in->aux;
440	panel->catalog = in->catalog;
441	panel->link = in->link;
442
443	dp_panel = &panel->dp_panel;
444	dp_panel->max_bw_code = DP_LINK_BW_8_1;
445	panel->aux_cfg_update_done = false;
446
447	return dp_panel;
448}
449
450void dp_panel_put(struct dp_panel *dp_panel)
451{
452	if (!dp_panel)
453		return;
454
455	kfree(dp_panel->edid);
456}
457