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
 17#include <linux/regulator/consumer.h>
 18
 19#include <video/of_videomode.h>
 20#include <video/videomode.h>
 21
 22#include "exynos_drm_drv.h"
 23
 24struct exynos_dpi {
 25	struct device *dev;
 26	struct device_node *panel_node;
 27
 28	struct drm_panel *panel;
 29	struct drm_connector connector;
 30	struct drm_encoder *encoder;
 31
 32	struct videomode *vm;
 33	int dpms_mode;
 34};
 35
 36#define connector_to_dpi(c) container_of(c, struct exynos_dpi, connector)
 37
 38static enum drm_connector_status
 39exynos_dpi_detect(struct drm_connector *connector, bool force)
 40{
 41	struct exynos_dpi *ctx = connector_to_dpi(connector);
 42
 43	/* panels supported only by boot-loader are always connected */
 44	if (!ctx->panel_node)
 45		return connector_status_connected;
 46
 47	if (!ctx->panel) {
 48		ctx->panel = of_drm_find_panel(ctx->panel_node);
 49		if (ctx->panel)
 50			drm_panel_attach(ctx->panel, &ctx->connector);
 51	}
 52
 53	if (ctx->panel)
 54		return connector_status_connected;
 55
 56	return connector_status_disconnected;
 57}
 58
 59static void exynos_dpi_connector_destroy(struct drm_connector *connector)
 60{
 61	drm_sysfs_connector_remove(connector);
 62	drm_connector_cleanup(connector);
 63}
 64
 65static struct drm_connector_funcs exynos_dpi_connector_funcs = {
 66	.dpms = drm_helper_connector_dpms,
 67	.detect = exynos_dpi_detect,
 68	.fill_modes = drm_helper_probe_single_connector_modes,
 69	.destroy = exynos_dpi_connector_destroy,
 70};
 71
 72static int exynos_dpi_get_modes(struct drm_connector *connector)
 73{
 74	struct exynos_dpi *ctx = connector_to_dpi(connector);
 75
 76	/* fimd timings gets precedence over panel modes */
 77	if (ctx->vm) {
 78		struct drm_display_mode *mode;
 79
 80		mode = drm_mode_create(connector->dev);
 81		if (!mode) {
 82			DRM_ERROR("failed to create a new display mode\n");
 83			return 0;
 84		}
 85		drm_display_mode_from_videomode(ctx->vm, mode);
 86		mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 87		drm_mode_probed_add(connector, mode);
 88		return 1;
 89	}
 90
 91	if (ctx->panel)
 92		return ctx->panel->funcs->get_modes(ctx->panel);
 93
 94	return 0;
 95}
 96
 97static int exynos_dpi_mode_valid(struct drm_connector *connector,
 98				 struct drm_display_mode *mode)
 99{
100	return MODE_OK;
101}
102
103static struct drm_encoder *
104exynos_dpi_best_encoder(struct drm_connector *connector)
105{
106	struct exynos_dpi *ctx = connector_to_dpi(connector);
107
108	return ctx->encoder;
109}
110
111static struct drm_connector_helper_funcs exynos_dpi_connector_helper_funcs = {
112	.get_modes = exynos_dpi_get_modes,
113	.mode_valid = exynos_dpi_mode_valid,
114	.best_encoder = exynos_dpi_best_encoder,
115};
116
117static int exynos_dpi_create_connector(struct exynos_drm_display *display,
118				       struct drm_encoder *encoder)
119{
120	struct exynos_dpi *ctx = display->ctx;
121	struct drm_connector *connector = &ctx->connector;
122	int ret;
123
124	ctx->encoder = encoder;
125
126	if (ctx->panel_node)
127		connector->polled = DRM_CONNECTOR_POLL_CONNECT;
128	else
129		connector->polled = DRM_CONNECTOR_POLL_HPD;
130
131	ret = drm_connector_init(encoder->dev, connector,
132				 &exynos_dpi_connector_funcs,
133				 DRM_MODE_CONNECTOR_VGA);
134	if (ret) {
135		DRM_ERROR("failed to initialize connector with drm\n");
136		return ret;
137	}
138
139	drm_connector_helper_add(connector, &exynos_dpi_connector_helper_funcs);
140	drm_sysfs_connector_add(connector);
141	drm_mode_connector_attach_encoder(connector, encoder);
142
143	return 0;
144}
145
146static void exynos_dpi_poweron(struct exynos_dpi *ctx)
147{
148	if (ctx->panel)
149		drm_panel_enable(ctx->panel);
150}
151
152static void exynos_dpi_poweroff(struct exynos_dpi *ctx)
153{
154	if (ctx->panel)
155		drm_panel_disable(ctx->panel);
156}
157
158static void exynos_dpi_dpms(struct exynos_drm_display *display, int mode)
159{
160	struct exynos_dpi *ctx = display->ctx;
161
162	switch (mode) {
163	case DRM_MODE_DPMS_ON:
164		if (ctx->dpms_mode != DRM_MODE_DPMS_ON)
165				exynos_dpi_poweron(ctx);
166			break;
167	case DRM_MODE_DPMS_STANDBY:
168	case DRM_MODE_DPMS_SUSPEND:
169	case DRM_MODE_DPMS_OFF:
170		if (ctx->dpms_mode == DRM_MODE_DPMS_ON)
171			exynos_dpi_poweroff(ctx);
172		break;
173	default:
174		break;
175	};
176	ctx->dpms_mode = mode;
177}
178
179static struct exynos_drm_display_ops exynos_dpi_display_ops = {
180	.create_connector = exynos_dpi_create_connector,
181	.dpms = exynos_dpi_dpms
182};
183
184static struct exynos_drm_display exynos_dpi_display = {
185	.type = EXYNOS_DISPLAY_TYPE_LCD,
186	.ops = &exynos_dpi_display_ops,
187};
188
189/* of_* functions will be removed after merge of of_graph patches */
190static struct device_node *
191of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
192{
193	struct device_node *np;
194
195	for_each_child_of_node(parent, np) {
196		u32 r;
197
198		if (!np->name || of_node_cmp(np->name, name))
199			continue;
200
201		if (of_property_read_u32(np, "reg", &r) < 0)
202			r = 0;
203
204		if (reg == r)
205			break;
206	}
207
208	return np;
209}
210
211static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
212						    u32 reg)
213{
214	struct device_node *ports, *port;
215
216	ports = of_get_child_by_name(parent, "ports");
217	if (ports)
218		parent = ports;
219
220	port = of_get_child_by_name_reg(parent, "port", reg);
221
222	of_node_put(ports);
223
224	return port;
225}
226
227static struct device_node *
228of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
229{
230	return of_get_child_by_name_reg(port, "endpoint", reg);
231}
232
233static struct device_node *
234of_graph_get_remote_port_parent(const struct device_node *node)
235{
236	struct device_node *np;
237	unsigned int depth;
238
239	np = of_parse_phandle(node, "remote-endpoint", 0);
240
241	/* Walk 3 levels up only if there is 'ports' node. */
242	for (depth = 3; depth && np; depth--) {
243		np = of_get_next_parent(np);
244		if (depth == 2 && of_node_cmp(np->name, "ports"))
245			break;
246	}
247	return np;
248}
249
250enum {
251	FIMD_PORT_IN0,
252	FIMD_PORT_IN1,
253	FIMD_PORT_IN2,
254	FIMD_PORT_RGB,
255	FIMD_PORT_WRB,
256};
257
258static struct device_node *exynos_dpi_of_find_panel_node(struct device *dev)
259{
260	struct device_node *np, *ep;
261
262	np = of_graph_get_port_by_reg(dev->of_node, FIMD_PORT_RGB);
263	if (!np)
264		return NULL;
265
266	ep = of_graph_get_endpoint_by_reg(np, 0);
267	of_node_put(np);
268	if (!ep)
269		return NULL;
270
271	np = of_graph_get_remote_port_parent(ep);
272	of_node_put(ep);
273
274	return np;
275}
276
277static int exynos_dpi_parse_dt(struct exynos_dpi *ctx)
278{
279	struct device *dev = ctx->dev;
280	struct device_node *dn = dev->of_node;
281	struct device_node *np;
282
283	ctx->panel_node = exynos_dpi_of_find_panel_node(dev);
284
285	np = of_get_child_by_name(dn, "display-timings");
286	if (np) {
287		struct videomode *vm;
288		int ret;
289
290		of_node_put(np);
291
292		vm = devm_kzalloc(dev, sizeof(*ctx->vm), GFP_KERNEL);
293		if (!vm)
294			return -ENOMEM;
295
296		ret = of_get_videomode(dn, vm, 0);
297		if (ret < 0)
298			return ret;
299
300		ctx->vm = vm;
301
302		return 0;
303	}
304
305	if (!ctx->panel_node)
306		return -EINVAL;
307
308	return 0;
309}
310
311int exynos_dpi_probe(struct device *dev)
312{
313	struct exynos_dpi *ctx;
314	int ret;
315
316	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
317	if (!ctx)
318		return -ENOMEM;
319
320	ctx->dev = dev;
321	exynos_dpi_display.ctx = ctx;
322	ctx->dpms_mode = DRM_MODE_DPMS_OFF;
323
324	ret = exynos_dpi_parse_dt(ctx);
325	if (ret < 0)
326		return ret;
327
328	exynos_drm_display_register(&exynos_dpi_display);
329
330	return 0;
331}
332
333int exynos_dpi_remove(struct device *dev)
334{
335	exynos_dpi_dpms(&exynos_dpi_display, DRM_MODE_DPMS_OFF);
336	exynos_drm_display_unregister(&exynos_dpi_display);
337
338	return 0;
339}