xref: /linux/drivers/gpu/drm/tve200/tve200_drv.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
4  * Parts of this file were based on sources as follows:
5  *
6  * Copyright (C) 2006-2008 Intel Corporation
7  * Copyright (C) 2007 Amos Lee <amos_lee@storlinksemi.com>
8  * Copyright (C) 2007 Dave Airlie <airlied@linux.ie>
9  * Copyright (C) 2011 Texas Instruments
10  * Copyright (C) 2017 Eric Anholt
11  */
12 
13 /**
14  * DOC: Faraday TV Encoder TVE200 DRM Driver
15  *
16  * The Faraday TV Encoder TVE200 is also known as the Gemini TV Interface
17  * Controller (TVC) and is found in the Gemini Chipset from Storlink
18  * Semiconductor (later Storm Semiconductor, later Cortina Systems)
19  * but also in the Grain Media GM8180 chipset. On the Gemini the module
20  * is connected to 8 data lines and a single clock line, comprising an
21  * 8-bit BT.656 interface.
22  *
23  * This is a very basic YUV display driver. The datasheet specifies that
24  * it supports the ITU BT.656 standard. It requires a 27 MHz clock which is
25  * the hallmark of any TV encoder supporting both PAL and NTSC.
26  *
27  * This driver exposes a standard KMS interface for this TV encoder.
28  */
29 
30 #include <linux/clk.h>
31 #include <linux/dma-buf.h>
32 #include <linux/irq.h>
33 #include <linux/io.h>
34 #include <linux/module.h>
35 #include <linux/of.h>
36 #include <linux/platform_device.h>
37 #include <linux/shmem_fs.h>
38 #include <linux/slab.h>
39 
40 #include <drm/drm_atomic_helper.h>
41 #include <drm/drm_bridge.h>
42 #include <drm/drm_client_setup.h>
43 #include <drm/drm_drv.h>
44 #include <drm/drm_fbdev_dma.h>
45 #include <drm/drm_fourcc.h>
46 #include <drm/drm_gem_dma_helper.h>
47 #include <drm/drm_gem_framebuffer_helper.h>
48 #include <drm/drm_module.h>
49 #include <drm/drm_of.h>
50 #include <drm/drm_panel.h>
51 #include <drm/drm_probe_helper.h>
52 #include <drm/drm_vblank.h>
53 
54 #include "tve200_drm.h"
55 
56 #define DRIVER_DESC      "DRM module for Faraday TVE200"
57 
58 static const struct drm_mode_config_funcs mode_config_funcs = {
59 	.fb_create = drm_gem_fb_create,
60 	.atomic_check = drm_atomic_helper_check,
61 	.atomic_commit = drm_atomic_helper_commit,
62 };
63 
64 static int tve200_modeset_init(struct drm_device *dev)
65 {
66 	struct drm_mode_config *mode_config;
67 	struct tve200_drm_dev_private *priv = dev->dev_private;
68 	struct drm_panel *panel;
69 	struct drm_bridge *bridge;
70 	int ret;
71 
72 	drm_mode_config_init(dev);
73 	mode_config = &dev->mode_config;
74 	mode_config->funcs = &mode_config_funcs;
75 	mode_config->min_width = 352;
76 	mode_config->max_width = 720;
77 	mode_config->min_height = 240;
78 	mode_config->max_height = 576;
79 
80 	ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
81 					  0, 0, &panel, &bridge);
82 	if (ret && ret != -ENODEV)
83 		return ret;
84 	if (panel) {
85 		bridge = drm_panel_bridge_add_typed(panel,
86 						    DRM_MODE_CONNECTOR_Unknown);
87 		if (IS_ERR(bridge)) {
88 			ret = PTR_ERR(bridge);
89 			goto out_bridge;
90 		}
91 	} else {
92 		/*
93 		 * TODO: when we are using a different bridge than a panel
94 		 * (such as a dumb VGA connector) we need to devise a different
95 		 * method to get the connector out of the bridge.
96 		 */
97 		dev_err(dev->dev, "the bridge is not a panel\n");
98 		ret = -EINVAL;
99 		goto out_bridge;
100 	}
101 
102 	ret = tve200_display_init(dev);
103 	if (ret) {
104 		dev_err(dev->dev, "failed to init display\n");
105 		goto out_bridge;
106 	}
107 
108 	ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
109 						    bridge);
110 	if (ret) {
111 		dev_err(dev->dev, "failed to attach bridge\n");
112 		goto out_bridge;
113 	}
114 
115 	priv->panel = panel;
116 	priv->connector = drm_panel_bridge_connector(bridge);
117 	priv->bridge = bridge;
118 
119 	dev_info(dev->dev, "attached to panel %s\n",
120 		 dev_name(panel->dev));
121 
122 	ret = drm_vblank_init(dev, 1);
123 	if (ret) {
124 		dev_err(dev->dev, "failed to init vblank\n");
125 		goto out_bridge;
126 	}
127 
128 	drm_mode_config_reset(dev);
129 	drm_kms_helper_poll_init(dev);
130 
131 	goto finish;
132 
133 out_bridge:
134 	if (panel)
135 		drm_panel_bridge_remove(bridge);
136 	drm_mode_config_cleanup(dev);
137 finish:
138 	return ret;
139 }
140 
141 DEFINE_DRM_GEM_DMA_FOPS(drm_fops);
142 
143 static const struct drm_driver tve200_drm_driver = {
144 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
145 	.ioctls = NULL,
146 	.fops = &drm_fops,
147 	.name = "tve200",
148 	.desc = DRIVER_DESC,
149 	.date = "20170703",
150 	.major = 1,
151 	.minor = 0,
152 	.patchlevel = 0,
153 	DRM_GEM_DMA_DRIVER_OPS,
154 	DRM_FBDEV_DMA_DRIVER_OPS,
155 };
156 
157 static int tve200_probe(struct platform_device *pdev)
158 {
159 	struct device *dev = &pdev->dev;
160 	struct tve200_drm_dev_private *priv;
161 	struct drm_device *drm;
162 	int irq;
163 	int ret;
164 
165 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
166 	if (!priv)
167 		return -ENOMEM;
168 
169 	drm = drm_dev_alloc(&tve200_drm_driver, dev);
170 	if (IS_ERR(drm))
171 		return PTR_ERR(drm);
172 	platform_set_drvdata(pdev, drm);
173 	priv->drm = drm;
174 	drm->dev_private = priv;
175 
176 	/* Clock the silicon so we can access the registers */
177 	priv->pclk = devm_clk_get(dev, "PCLK");
178 	if (IS_ERR(priv->pclk)) {
179 		dev_err(dev, "unable to get PCLK\n");
180 		ret = PTR_ERR(priv->pclk);
181 		goto dev_unref;
182 	}
183 	ret = clk_prepare_enable(priv->pclk);
184 	if (ret) {
185 		dev_err(dev, "failed to enable PCLK\n");
186 		goto dev_unref;
187 	}
188 
189 	/* This clock is for the pixels (27MHz) */
190 	priv->clk = devm_clk_get(dev, "TVE");
191 	if (IS_ERR(priv->clk)) {
192 		dev_err(dev, "unable to get TVE clock\n");
193 		ret = PTR_ERR(priv->clk);
194 		goto clk_disable;
195 	}
196 
197 	priv->regs = devm_platform_ioremap_resource(pdev, 0);
198 	if (IS_ERR(priv->regs)) {
199 		dev_err(dev, "%s failed mmio\n", __func__);
200 		ret = -EINVAL;
201 		goto clk_disable;
202 	}
203 
204 	irq = platform_get_irq(pdev, 0);
205 	if (irq < 0) {
206 		ret = irq;
207 		goto clk_disable;
208 	}
209 
210 	/* turn off interrupts before requesting the irq */
211 	writel(0, priv->regs + TVE200_INT_EN);
212 
213 	ret = devm_request_irq(dev, irq, tve200_irq, 0, "tve200", priv);
214 	if (ret) {
215 		dev_err(dev, "failed to request irq %d\n", ret);
216 		goto clk_disable;
217 	}
218 
219 	ret = tve200_modeset_init(drm);
220 	if (ret)
221 		goto clk_disable;
222 
223 	ret = drm_dev_register(drm, 0);
224 	if (ret < 0)
225 		goto clk_disable;
226 
227 	drm_client_setup_with_fourcc(drm, DRM_FORMAT_RGB565);
228 
229 	return 0;
230 
231 clk_disable:
232 	clk_disable_unprepare(priv->pclk);
233 dev_unref:
234 	drm_dev_put(drm);
235 	return ret;
236 }
237 
238 static void tve200_remove(struct platform_device *pdev)
239 {
240 	struct drm_device *drm = platform_get_drvdata(pdev);
241 	struct tve200_drm_dev_private *priv = drm->dev_private;
242 
243 	drm_dev_unregister(drm);
244 	drm_atomic_helper_shutdown(drm);
245 	if (priv->panel)
246 		drm_panel_bridge_remove(priv->bridge);
247 	drm_mode_config_cleanup(drm);
248 	clk_disable_unprepare(priv->pclk);
249 	drm_dev_put(drm);
250 }
251 
252 static void tve200_shutdown(struct platform_device *pdev)
253 {
254 	drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
255 }
256 
257 static const struct of_device_id tve200_of_match[] = {
258 	{
259 		.compatible = "faraday,tve200",
260 	},
261 	{},
262 };
263 
264 static struct platform_driver tve200_driver = {
265 	.driver = {
266 		.name           = "tve200",
267 		.of_match_table = tve200_of_match,
268 	},
269 	.probe = tve200_probe,
270 	.remove_new = tve200_remove,
271 	.shutdown = tve200_shutdown,
272 };
273 drm_module_platform_driver(tve200_driver);
274 
275 MODULE_DESCRIPTION(DRIVER_DESC);
276 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
277 MODULE_LICENSE("GPL");
278