1/*
2 * Copyright (C) 2012 Texas Instruments
3 * Author: Rob Clark <robdclark@gmail.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program.  If not, see <http://www.gnu.org/licenses/>.
16 */
17
18#include <linux/pinctrl/pinmux.h>
19#include <linux/pinctrl/consumer.h>
20#include <linux/backlight.h>
21#include <linux/gpio/consumer.h>
22#include <video/display_timing.h>
23#include <video/of_display_timing.h>
24#include <video/videomode.h>
25
26#include "tilcdc_drv.h"
27
28struct panel_module {
29	struct tilcdc_module base;
30	struct tilcdc_panel_info *info;
31	struct display_timings *timings;
32	struct backlight_device *backlight;
33	struct gpio_desc *enable_gpio;
34};
35#define to_panel_module(x) container_of(x, struct panel_module, base)
36
37
38/*
39 * Encoder:
40 */
41
42struct panel_encoder {
43	struct drm_encoder base;
44	struct panel_module *mod;
45};
46#define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
47
48
49static void panel_encoder_destroy(struct drm_encoder *encoder)
50{
51	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
52	drm_encoder_cleanup(encoder);
53	kfree(panel_encoder);
54}
55
56static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
57{
58	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
59	struct backlight_device *backlight = panel_encoder->mod->backlight;
60	struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
61
62	if (backlight) {
63		backlight->props.power = mode == DRM_MODE_DPMS_ON ?
64					 FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
65		backlight_update_status(backlight);
66	}
67
68	if (gpio)
69		gpiod_set_value_cansleep(gpio,
70					 mode == DRM_MODE_DPMS_ON ? 1 : 0);
71}
72
73static bool panel_encoder_mode_fixup(struct drm_encoder *encoder,
74		const struct drm_display_mode *mode,
75		struct drm_display_mode *adjusted_mode)
76{
77	/* nothing needed */
78	return true;
79}
80
81static void panel_encoder_prepare(struct drm_encoder *encoder)
82{
83	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
84	panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
85	tilcdc_crtc_set_panel_info(encoder->crtc, panel_encoder->mod->info);
86}
87
88static void panel_encoder_commit(struct drm_encoder *encoder)
89{
90	panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
91}
92
93static void panel_encoder_mode_set(struct drm_encoder *encoder,
94		struct drm_display_mode *mode,
95		struct drm_display_mode *adjusted_mode)
96{
97	/* nothing needed */
98}
99
100static const struct drm_encoder_funcs panel_encoder_funcs = {
101		.destroy        = panel_encoder_destroy,
102};
103
104static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
105		.dpms           = panel_encoder_dpms,
106		.mode_fixup     = panel_encoder_mode_fixup,
107		.prepare        = panel_encoder_prepare,
108		.commit         = panel_encoder_commit,
109		.mode_set       = panel_encoder_mode_set,
110};
111
112static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
113		struct panel_module *mod)
114{
115	struct panel_encoder *panel_encoder;
116	struct drm_encoder *encoder;
117	int ret;
118
119	panel_encoder = kzalloc(sizeof(*panel_encoder), GFP_KERNEL);
120	if (!panel_encoder) {
121		dev_err(dev->dev, "allocation failed\n");
122		return NULL;
123	}
124
125	panel_encoder->mod = mod;
126
127	encoder = &panel_encoder->base;
128	encoder->possible_crtcs = 1;
129
130	ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
131			DRM_MODE_ENCODER_LVDS);
132	if (ret < 0)
133		goto fail;
134
135	drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
136
137	return encoder;
138
139fail:
140	panel_encoder_destroy(encoder);
141	return NULL;
142}
143
144/*
145 * Connector:
146 */
147
148struct panel_connector {
149	struct drm_connector base;
150
151	struct drm_encoder *encoder;  /* our connected encoder */
152	struct panel_module *mod;
153};
154#define to_panel_connector(x) container_of(x, struct panel_connector, base)
155
156
157static void panel_connector_destroy(struct drm_connector *connector)
158{
159	struct panel_connector *panel_connector = to_panel_connector(connector);
160	drm_connector_unregister(connector);
161	drm_connector_cleanup(connector);
162	kfree(panel_connector);
163}
164
165static enum drm_connector_status panel_connector_detect(
166		struct drm_connector *connector,
167		bool force)
168{
169	return connector_status_connected;
170}
171
172static int panel_connector_get_modes(struct drm_connector *connector)
173{
174	struct drm_device *dev = connector->dev;
175	struct panel_connector *panel_connector = to_panel_connector(connector);
176	struct display_timings *timings = panel_connector->mod->timings;
177	int i;
178
179	for (i = 0; i < timings->num_timings; i++) {
180		struct drm_display_mode *mode = drm_mode_create(dev);
181		struct videomode vm;
182
183		if (videomode_from_timings(timings, &vm, i))
184			break;
185
186		drm_display_mode_from_videomode(&vm, mode);
187
188		mode->type = DRM_MODE_TYPE_DRIVER;
189
190		if (timings->native_mode == i)
191			mode->type |= DRM_MODE_TYPE_PREFERRED;
192
193		drm_mode_set_name(mode);
194		drm_mode_probed_add(connector, mode);
195	}
196
197	return i;
198}
199
200static int panel_connector_mode_valid(struct drm_connector *connector,
201		  struct drm_display_mode *mode)
202{
203	struct tilcdc_drm_private *priv = connector->dev->dev_private;
204	/* our only constraints are what the crtc can generate: */
205	return tilcdc_crtc_mode_valid(priv->crtc, mode);
206}
207
208static struct drm_encoder *panel_connector_best_encoder(
209		struct drm_connector *connector)
210{
211	struct panel_connector *panel_connector = to_panel_connector(connector);
212	return panel_connector->encoder;
213}
214
215static const struct drm_connector_funcs panel_connector_funcs = {
216	.destroy            = panel_connector_destroy,
217	.dpms               = drm_helper_connector_dpms,
218	.detect             = panel_connector_detect,
219	.fill_modes         = drm_helper_probe_single_connector_modes,
220};
221
222static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
223	.get_modes          = panel_connector_get_modes,
224	.mode_valid         = panel_connector_mode_valid,
225	.best_encoder       = panel_connector_best_encoder,
226};
227
228static struct drm_connector *panel_connector_create(struct drm_device *dev,
229		struct panel_module *mod, struct drm_encoder *encoder)
230{
231	struct panel_connector *panel_connector;
232	struct drm_connector *connector;
233	int ret;
234
235	panel_connector = kzalloc(sizeof(*panel_connector), GFP_KERNEL);
236	if (!panel_connector) {
237		dev_err(dev->dev, "allocation failed\n");
238		return NULL;
239	}
240
241	panel_connector->encoder = encoder;
242	panel_connector->mod = mod;
243
244	connector = &panel_connector->base;
245
246	drm_connector_init(dev, connector, &panel_connector_funcs,
247			DRM_MODE_CONNECTOR_LVDS);
248	drm_connector_helper_add(connector, &panel_connector_helper_funcs);
249
250	connector->interlace_allowed = 0;
251	connector->doublescan_allowed = 0;
252
253	ret = drm_mode_connector_attach_encoder(connector, encoder);
254	if (ret)
255		goto fail;
256
257	drm_connector_register(connector);
258
259	return connector;
260
261fail:
262	panel_connector_destroy(connector);
263	return NULL;
264}
265
266/*
267 * Module:
268 */
269
270static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
271{
272	struct panel_module *panel_mod = to_panel_module(mod);
273	struct tilcdc_drm_private *priv = dev->dev_private;
274	struct drm_encoder *encoder;
275	struct drm_connector *connector;
276
277	encoder = panel_encoder_create(dev, panel_mod);
278	if (!encoder)
279		return -ENOMEM;
280
281	connector = panel_connector_create(dev, panel_mod, encoder);
282	if (!connector)
283		return -ENOMEM;
284
285	priv->encoders[priv->num_encoders++] = encoder;
286	priv->connectors[priv->num_connectors++] = connector;
287
288	return 0;
289}
290
291static const struct tilcdc_module_ops panel_module_ops = {
292		.modeset_init = panel_modeset_init,
293};
294
295/*
296 * Device:
297 */
298
299/* maybe move this somewhere common if it is needed by other outputs? */
300static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
301{
302	struct device_node *info_np;
303	struct tilcdc_panel_info *info;
304	int ret = 0;
305
306	if (!np) {
307		pr_err("%s: no devicenode given\n", __func__);
308		return NULL;
309	}
310
311	info_np = of_get_child_by_name(np, "panel-info");
312	if (!info_np) {
313		pr_err("%s: could not find panel-info node\n", __func__);
314		return NULL;
315	}
316
317	info = kzalloc(sizeof(*info), GFP_KERNEL);
318	if (!info) {
319		pr_err("%s: allocation failed\n", __func__);
320		of_node_put(info_np);
321		return NULL;
322	}
323
324	ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
325	ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
326	ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
327	ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
328	ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
329	ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
330	ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
331	ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
332	ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
333
334	/* optional: */
335	info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
336	info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
337
338	if (ret) {
339		pr_err("%s: error reading panel-info properties\n", __func__);
340		kfree(info);
341		of_node_put(info_np);
342		return NULL;
343	}
344	of_node_put(info_np);
345
346	return info;
347}
348
349static int panel_probe(struct platform_device *pdev)
350{
351	struct device_node *bl_node, *node = pdev->dev.of_node;
352	struct panel_module *panel_mod;
353	struct tilcdc_module *mod;
354	struct pinctrl *pinctrl;
355	int ret;
356
357	/* bail out early if no DT data: */
358	if (!node) {
359		dev_err(&pdev->dev, "device-tree data is missing\n");
360		return -ENXIO;
361	}
362
363	panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
364	if (!panel_mod)
365		return -ENOMEM;
366
367	bl_node = of_parse_phandle(node, "backlight", 0);
368	if (bl_node) {
369		panel_mod->backlight = of_find_backlight_by_node(bl_node);
370		of_node_put(bl_node);
371
372		if (!panel_mod->backlight)
373			return -EPROBE_DEFER;
374
375		dev_info(&pdev->dev, "found backlight\n");
376	}
377
378	panel_mod->enable_gpio = devm_gpiod_get(&pdev->dev, "enable");
379	if (IS_ERR(panel_mod->enable_gpio)) {
380		ret = PTR_ERR(panel_mod->enable_gpio);
381		if (ret != -ENOENT) {
382			dev_err(&pdev->dev, "failed to request enable GPIO\n");
383			goto fail_backlight;
384		}
385
386		/* Optional GPIO is not here, continue silently. */
387		panel_mod->enable_gpio = NULL;
388	} else {
389		ret = gpiod_direction_output(panel_mod->enable_gpio, 0);
390		if (ret < 0) {
391			dev_err(&pdev->dev, "failed to setup GPIO\n");
392			goto fail_backlight;
393		}
394		dev_info(&pdev->dev, "found enable GPIO\n");
395	}
396
397	mod = &panel_mod->base;
398	pdev->dev.platform_data = mod;
399
400	tilcdc_module_init(mod, "panel", &panel_module_ops);
401
402	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
403	if (IS_ERR(pinctrl))
404		dev_warn(&pdev->dev, "pins are not configured\n");
405
406	panel_mod->timings = of_get_display_timings(node);
407	if (!panel_mod->timings) {
408		dev_err(&pdev->dev, "could not get panel timings\n");
409		ret = -EINVAL;
410		goto fail_free;
411	}
412
413	panel_mod->info = of_get_panel_info(node);
414	if (!panel_mod->info) {
415		dev_err(&pdev->dev, "could not get panel info\n");
416		ret = -EINVAL;
417		goto fail_timings;
418	}
419
420	mod->preferred_bpp = panel_mod->info->bpp;
421
422	return 0;
423
424fail_timings:
425	display_timings_release(panel_mod->timings);
426
427fail_free:
428	tilcdc_module_cleanup(mod);
429
430fail_backlight:
431	if (panel_mod->backlight)
432		put_device(&panel_mod->backlight->dev);
433	return ret;
434}
435
436static int panel_remove(struct platform_device *pdev)
437{
438	struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
439	struct panel_module *panel_mod = to_panel_module(mod);
440	struct backlight_device *backlight = panel_mod->backlight;
441
442	if (backlight)
443		put_device(&backlight->dev);
444
445	display_timings_release(panel_mod->timings);
446
447	tilcdc_module_cleanup(mod);
448	kfree(panel_mod->info);
449
450	return 0;
451}
452
453static struct of_device_id panel_of_match[] = {
454		{ .compatible = "ti,tilcdc,panel", },
455		{ },
456};
457
458struct platform_driver panel_driver = {
459	.probe = panel_probe,
460	.remove = panel_remove,
461	.driver = {
462		.owner = THIS_MODULE,
463		.name = "panel",
464		.of_match_table = panel_of_match,
465	},
466};
467
468int __init tilcdc_panel_init(void)
469{
470	return platform_driver_register(&panel_driver);
471}
472
473void __exit tilcdc_panel_fini(void)
474{
475	platform_driver_unregister(&panel_driver);
476}
477