1/*
  2 * Exynos DRM Parallel output support.
  3 *
  4 * Copyright (c) 2014 Samsung Electronics Co., Ltd
  5 *
  6 * Contacts: Andrzej Hajda <a.hajda@samsung.com>
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License version 2 as
 10 * published by the Free Software Foundation.
 11*/
 12
 13#include <drm/drmP.h>
 14#include <drm/drm_crtc_helper.h>
 15#include <drm/drm_panel.h>
 16#include <drm/drm_atomic_helper.h>
 17
 18#include <linux/regulator/consumer.h>
 19
 20#include <video/of_videomode.h>
 21#include <video/videomode.h>
 22
 23#include "exynos_drm_crtc.h"
 24
 25struct exynos_dpi {
 26	struct drm_encoder encoder;
 27	struct device *dev;
 28	struct device_node *panel_node;
 29
 30	struct drm_panel *panel;
 31	struct drm_connector connector;
 32
 33	struct videomode *vm;
 34};
 35
 36#define connector_to_dpi(c) container_of(c, struct exynos_dpi, connector)
 37
 38static inline struct exynos_dpi *encoder_to_dpi(struct drm_encoder *e)
 39{
 40	return container_of(e, struct exynos_dpi, encoder);
 41}
 42
 43static enum drm_connector_status
 44exynos_dpi_detect(struct drm_connector *connector, bool force)
 45{
 46	struct exynos_dpi *ctx = connector_to_dpi(connector);
 47
 48	if (ctx->panel && !ctx->panel->connector)
 49		drm_panel_attach(ctx->panel, &ctx->connector);
 50
 51	return connector_status_connected;
 52}
 53
 54static void exynos_dpi_connector_destroy(struct drm_connector *connector)
 55{
 56	drm_connector_unregister(connector);
 57	drm_connector_cleanup(connector);
 58}
 59
 60static const struct drm_connector_funcs exynos_dpi_connector_funcs = {
 61	.dpms = drm_atomic_helper_connector_dpms,
 62	.detect = exynos_dpi_detect,
 63	.fill_modes = drm_helper_probe_single_connector_modes,
 64	.destroy = exynos_dpi_connector_destroy,
 65	.reset = drm_atomic_helper_connector_reset,
 66	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 67	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 68};
 69
 70static int exynos_dpi_get_modes(struct drm_connector *connector)
 71{
 72	struct exynos_dpi *ctx = connector_to_dpi(connector);
 73
 74	/* fimd timings gets precedence over panel modes */
 75	if (ctx->vm) {
 76		struct drm_display_mode *mode;
 77
 78		mode = drm_mode_create(connector->dev);
 79		if (!mode) {
 80			DRM_ERROR("failed to create a new display mode\n");
 81			return 0;
 82		}
 83		drm_display_mode_from_videomode(ctx->vm, mode);
 84		mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 85		drm_mode_probed_add(connector, mode);
 86		return 1;
 87	}
 88
 89	if (ctx->panel)
 90		return ctx->panel->funcs->get_modes(ctx->panel);
 91
 92	return 0;
 93}
 94
 95static struct drm_encoder *
 96exynos_dpi_best_encoder(struct drm_connector *connector)
 97{
 98	struct exynos_dpi *ctx = connector_to_dpi(connector);
 99
100	return &ctx->encoder;
101}
102
103static const struct drm_connector_helper_funcs exynos_dpi_connector_helper_funcs = {
104	.get_modes = exynos_dpi_get_modes,
105	.best_encoder = exynos_dpi_best_encoder,
106};
107
108static int exynos_dpi_create_connector(struct drm_encoder *encoder)
109{
110	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
111	struct drm_connector *connector = &ctx->connector;
112	int ret;
113
114	connector->polled = DRM_CONNECTOR_POLL_HPD;
115
116	ret = drm_connector_init(encoder->dev, connector,
117				 &exynos_dpi_connector_funcs,
118				 DRM_MODE_CONNECTOR_VGA);
119	if (ret) {
120		DRM_ERROR("failed to initialize connector with drm\n");
121		return ret;
122	}
123
124	drm_connector_helper_add(connector, &exynos_dpi_connector_helper_funcs);
125	drm_connector_register(connector);
126	drm_mode_connector_attach_encoder(connector, encoder);
127
128	return 0;
129}
130
131static void exynos_dpi_mode_set(struct drm_encoder *encoder,
132				struct drm_display_mode *mode,
133				struct drm_display_mode *adjusted_mode)
134{
135}
136
137static void exynos_dpi_enable(struct drm_encoder *encoder)
138{
139	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
140
141	if (ctx->panel) {
142		drm_panel_prepare(ctx->panel);
143		drm_panel_enable(ctx->panel);
144	}
145}
146
147static void exynos_dpi_disable(struct drm_encoder *encoder)
148{
149	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
150
151	if (ctx->panel) {
152		drm_panel_disable(ctx->panel);
153		drm_panel_unprepare(ctx->panel);
154	}
155}
156
157static const struct drm_encoder_helper_funcs exynos_dpi_encoder_helper_funcs = {
158	.mode_set = exynos_dpi_mode_set,
159	.enable = exynos_dpi_enable,
160	.disable = exynos_dpi_disable,
161};
162
163static const struct drm_encoder_funcs exynos_dpi_encoder_funcs = {
164	.destroy = drm_encoder_cleanup,
165};
166
167/* of_* functions will be removed after merge of of_graph patches */
168static struct device_node *
169of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
170{
171	struct device_node *np;
172
173	for_each_child_of_node(parent, np) {
174		u32 r;
175
176		if (!np->name || of_node_cmp(np->name, name))
177			continue;
178
179		if (of_property_read_u32(np, "reg", &r) < 0)
180			r = 0;
181
182		if (reg == r)
183			break;
184	}
185
186	return np;
187}
188
189static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
190						    u32 reg)
191{
192	struct device_node *ports, *port;
193
194	ports = of_get_child_by_name(parent, "ports");
195	if (ports)
196		parent = ports;
197
198	port = of_get_child_by_name_reg(parent, "port", reg);
199
200	of_node_put(ports);
201
202	return port;
203}
204
205static struct device_node *
206of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
207{
208	return of_get_child_by_name_reg(port, "endpoint", reg);
209}
210
211static struct device_node *
212of_graph_get_remote_port_parent(const struct device_node *node)
213{
214	struct device_node *np;
215	unsigned int depth;
216
217	np = of_parse_phandle(node, "remote-endpoint", 0);
218
219	/* Walk 3 levels up only if there is 'ports' node. */
220	for (depth = 3; depth && np; depth--) {
221		np = of_get_next_parent(np);
222		if (depth == 2 && of_node_cmp(np->name, "ports"))
223			break;
224	}
225	return np;
226}
227
228enum {
229	FIMD_PORT_IN0,
230	FIMD_PORT_IN1,
231	FIMD_PORT_IN2,
232	FIMD_PORT_RGB,
233	FIMD_PORT_WRB,
234};
235
236static struct device_node *exynos_dpi_of_find_panel_node(struct device *dev)
237{
238	struct device_node *np, *ep;
239
240	np = of_graph_get_port_by_reg(dev->of_node, FIMD_PORT_RGB);
241	if (!np)
242		return NULL;
243
244	ep = of_graph_get_endpoint_by_reg(np, 0);
245	of_node_put(np);
246	if (!ep)
247		return NULL;
248
249	np = of_graph_get_remote_port_parent(ep);
250	of_node_put(ep);
251
252	return np;
253}
254
255static int exynos_dpi_parse_dt(struct exynos_dpi *ctx)
256{
257	struct device *dev = ctx->dev;
258	struct device_node *dn = dev->of_node;
259	struct device_node *np;
260
261	ctx->panel_node = exynos_dpi_of_find_panel_node(dev);
262
263	np = of_get_child_by_name(dn, "display-timings");
264	if (np) {
265		struct videomode *vm;
266		int ret;
267
268		of_node_put(np);
269
270		vm = devm_kzalloc(dev, sizeof(*ctx->vm), GFP_KERNEL);
271		if (!vm)
272			return -ENOMEM;
273
274		ret = of_get_videomode(dn, vm, 0);
275		if (ret < 0) {
276			devm_kfree(dev, vm);
277			return ret;
278		}
279
280		ctx->vm = vm;
281
282		return 0;
283	}
284
285	if (!ctx->panel_node)
286		return -EINVAL;
287
288	return 0;
289}
290
291int exynos_dpi_bind(struct drm_device *dev, struct drm_encoder *encoder)
292{
293	int ret;
294
295	ret = exynos_drm_crtc_get_pipe_from_type(dev, EXYNOS_DISPLAY_TYPE_LCD);
296	if (ret < 0)
297		return ret;
298
299	encoder->possible_crtcs = 1 << ret;
300
301	DRM_DEBUG_KMS("possible_crtcs = 0x%x\n", encoder->possible_crtcs);
302
303	drm_encoder_init(dev, encoder, &exynos_dpi_encoder_funcs,
304			 DRM_MODE_ENCODER_TMDS, NULL);
305
306	drm_encoder_helper_add(encoder, &exynos_dpi_encoder_helper_funcs);
307
308	ret = exynos_dpi_create_connector(encoder);
309	if (ret) {
310		DRM_ERROR("failed to create connector ret = %d\n", ret);
311		drm_encoder_cleanup(encoder);
312		return ret;
313	}
314
315	return 0;
316}
317
318struct drm_encoder *exynos_dpi_probe(struct device *dev)
319{
320	struct exynos_dpi *ctx;
321	int ret;
322
323	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
324	if (!ctx)
325		return ERR_PTR(-ENOMEM);
326
327	ctx->dev = dev;
328
329	ret = exynos_dpi_parse_dt(ctx);
330	if (ret < 0) {
331		devm_kfree(dev, ctx);
332		return NULL;
333	}
334
335	if (ctx->panel_node) {
336		ctx->panel = of_drm_find_panel(ctx->panel_node);
337		if (!ctx->panel)
338			return ERR_PTR(-EPROBE_DEFER);
339	}
340
341	return &ctx->encoder;
342}
343
344int exynos_dpi_remove(struct drm_encoder *encoder)
345{
346	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
347
348	exynos_dpi_disable(&ctx->encoder);
349
350	if (ctx->panel)
351		drm_panel_detach(ctx->panel);
352
353	return 0;
354}