1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 NextThing Co
4  * Copyright (C) 2016-2019 Bootlin
5  *
6  * Author: Maxime Ripard <maxime.ripard@bootlin.com>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/of_graph.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/reset.h>
20 #include <linux/videodev2.h>
21 
22 #include <media/v4l2-dev.h>
23 #include <media/v4l2-device.h>
24 #include <media/v4l2-fwnode.h>
25 #include <media/v4l2-ioctl.h>
26 #include <media/v4l2-mediabus.h>
27 
28 #include <media/videobuf2-core.h>
29 #include <media/videobuf2-dma-contig.h>
30 
31 #include "sun4i_csi.h"
32 
33 struct sun4i_csi_traits {
34 	unsigned int channels;
35 	unsigned int max_width;
36 	bool has_isp;
37 };
38 
39 static const struct media_entity_operations sun4i_csi_video_entity_ops = {
40 	.link_validate = v4l2_subdev_link_validate,
41 };
42 
43 static int sun4i_csi_notify_bound(struct v4l2_async_notifier *notifier,
44 				  struct v4l2_subdev *subdev,
45 				  struct v4l2_async_subdev *asd)
46 {
47 	struct sun4i_csi *csi = container_of(notifier, struct sun4i_csi,
48 					     notifier);
49 
50 	csi->src_subdev = subdev;
51 	csi->src_pad = media_entity_get_fwnode_pad(&subdev->entity,
52 						   subdev->fwnode,
53 						   MEDIA_PAD_FL_SOURCE);
54 	if (csi->src_pad < 0) {
55 		dev_err(csi->dev, "Couldn't find output pad for subdev %s\n",
56 			subdev->name);
57 		return csi->src_pad;
58 	}
59 
60 	dev_dbg(csi->dev, "Bound %s pad: %d\n", subdev->name, csi->src_pad);
61 	return 0;
62 }
63 
64 static int sun4i_csi_notify_complete(struct v4l2_async_notifier *notifier)
65 {
66 	struct sun4i_csi *csi = container_of(notifier, struct sun4i_csi,
67 					     notifier);
68 	struct v4l2_subdev *subdev = &csi->subdev;
69 	struct video_device *vdev = &csi->vdev;
70 	int ret;
71 
72 	ret = v4l2_device_register_subdev(&csi->v4l, subdev);
73 	if (ret < 0)
74 		return ret;
75 
76 	ret = sun4i_csi_v4l2_register(csi);
77 	if (ret < 0)
78 		return ret;
79 
80 	ret = media_device_register(&csi->mdev);
81 	if (ret)
82 		return ret;
83 
84 	/* Create link from subdev to main device */
85 	ret = media_create_pad_link(&subdev->entity, CSI_SUBDEV_SOURCE,
86 				    &vdev->entity, 0,
87 				    MEDIA_LNK_FL_ENABLED |
88 				    MEDIA_LNK_FL_IMMUTABLE);
89 	if (ret)
90 		goto err_clean_media;
91 
92 	ret = media_create_pad_link(&csi->src_subdev->entity, csi->src_pad,
93 				    &subdev->entity, CSI_SUBDEV_SINK,
94 				    MEDIA_LNK_FL_ENABLED |
95 				    MEDIA_LNK_FL_IMMUTABLE);
96 	if (ret)
97 		goto err_clean_media;
98 
99 	ret = v4l2_device_register_subdev_nodes(&csi->v4l);
100 	if (ret < 0)
101 		goto err_clean_media;
102 
103 	return 0;
104 
105 err_clean_media:
106 	media_device_unregister(&csi->mdev);
107 
108 	return ret;
109 }
110 
111 static const struct v4l2_async_notifier_operations sun4i_csi_notify_ops = {
112 	.bound		= sun4i_csi_notify_bound,
113 	.complete	= sun4i_csi_notify_complete,
114 };
115 
116 static int sun4i_csi_notifier_init(struct sun4i_csi *csi)
117 {
118 	struct v4l2_fwnode_endpoint vep = {
119 		.bus_type = V4L2_MBUS_PARALLEL,
120 	};
121 	struct v4l2_async_subdev *asd;
122 	struct fwnode_handle *ep;
123 	int ret;
124 
125 	v4l2_async_notifier_init(&csi->notifier);
126 
127 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi->dev), 0, 0,
128 					     FWNODE_GRAPH_ENDPOINT_NEXT);
129 	if (!ep)
130 		return -EINVAL;
131 
132 	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
133 	if (ret)
134 		goto out;
135 
136 	csi->bus = vep.bus.parallel;
137 
138 	asd = v4l2_async_notifier_add_fwnode_remote_subdev(&csi->notifier, ep,
139 							   struct v4l2_async_subdev);
140 	if (IS_ERR(asd)) {
141 		ret = PTR_ERR(asd);
142 		goto out;
143 	}
144 
145 	csi->notifier.ops = &sun4i_csi_notify_ops;
146 
147 out:
148 	fwnode_handle_put(ep);
149 	return ret;
150 }
151 
152 static int sun4i_csi_probe(struct platform_device *pdev)
153 {
154 	struct v4l2_subdev *subdev;
155 	struct video_device *vdev;
156 	struct sun4i_csi *csi;
157 	struct resource *res;
158 	int ret;
159 	int irq;
160 
161 	csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
162 	if (!csi)
163 		return -ENOMEM;
164 	platform_set_drvdata(pdev, csi);
165 	csi->dev = &pdev->dev;
166 	subdev = &csi->subdev;
167 	vdev = &csi->vdev;
168 
169 	csi->traits = of_device_get_match_data(&pdev->dev);
170 	if (!csi->traits)
171 		return -EINVAL;
172 
173 	csi->mdev.dev = csi->dev;
174 	strscpy(csi->mdev.model, "Allwinner Video Capture Device",
175 		sizeof(csi->mdev.model));
176 	csi->mdev.hw_revision = 0;
177 	snprintf(csi->mdev.bus_info, sizeof(csi->mdev.bus_info), "platform:%s",
178 		 dev_name(csi->dev));
179 	media_device_init(&csi->mdev);
180 	csi->v4l.mdev = &csi->mdev;
181 
182 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
183 	csi->regs = devm_ioremap_resource(&pdev->dev, res);
184 	if (IS_ERR(csi->regs))
185 		return PTR_ERR(csi->regs);
186 
187 	irq = platform_get_irq(pdev, 0);
188 	if (irq < 0)
189 		return irq;
190 
191 	csi->bus_clk = devm_clk_get(&pdev->dev, "bus");
192 	if (IS_ERR(csi->bus_clk)) {
193 		dev_err(&pdev->dev, "Couldn't get our bus clock\n");
194 		return PTR_ERR(csi->bus_clk);
195 	}
196 
197 	if (csi->traits->has_isp) {
198 		csi->isp_clk = devm_clk_get(&pdev->dev, "isp");
199 		if (IS_ERR(csi->isp_clk)) {
200 			dev_err(&pdev->dev, "Couldn't get our ISP clock\n");
201 			return PTR_ERR(csi->isp_clk);
202 		}
203 	}
204 
205 	csi->ram_clk = devm_clk_get(&pdev->dev, "ram");
206 	if (IS_ERR(csi->ram_clk)) {
207 		dev_err(&pdev->dev, "Couldn't get our ram clock\n");
208 		return PTR_ERR(csi->ram_clk);
209 	}
210 
211 	csi->rst = devm_reset_control_get(&pdev->dev, NULL);
212 	if (IS_ERR(csi->rst)) {
213 		dev_err(&pdev->dev, "Couldn't get our reset line\n");
214 		return PTR_ERR(csi->rst);
215 	}
216 
217 	/* Initialize subdev */
218 	v4l2_subdev_init(subdev, &sun4i_csi_subdev_ops);
219 	subdev->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
220 	subdev->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
221 	subdev->owner = THIS_MODULE;
222 	snprintf(subdev->name, sizeof(subdev->name), "sun4i-csi-0");
223 	v4l2_set_subdevdata(subdev, csi);
224 
225 	csi->subdev_pads[CSI_SUBDEV_SINK].flags =
226 		MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_MUST_CONNECT;
227 	csi->subdev_pads[CSI_SUBDEV_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
228 	ret = media_entity_pads_init(&subdev->entity, CSI_SUBDEV_PADS,
229 				     csi->subdev_pads);
230 	if (ret < 0)
231 		return ret;
232 
233 	csi->vdev_pad.flags = MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_MUST_CONNECT;
234 	vdev->entity.ops = &sun4i_csi_video_entity_ops;
235 	ret = media_entity_pads_init(&vdev->entity, 1, &csi->vdev_pad);
236 	if (ret < 0)
237 		return ret;
238 
239 	ret = sun4i_csi_dma_register(csi, irq);
240 	if (ret)
241 		goto err_clean_pad;
242 
243 	ret = sun4i_csi_notifier_init(csi);
244 	if (ret)
245 		goto err_unregister_media;
246 
247 	ret = v4l2_async_notifier_register(&csi->v4l, &csi->notifier);
248 	if (ret) {
249 		dev_err(csi->dev, "Couldn't register our notifier.\n");
250 		goto err_unregister_media;
251 	}
252 
253 	pm_runtime_enable(&pdev->dev);
254 
255 	return 0;
256 
257 err_unregister_media:
258 	media_device_unregister(&csi->mdev);
259 	sun4i_csi_dma_unregister(csi);
260 
261 err_clean_pad:
262 	media_device_cleanup(&csi->mdev);
263 
264 	return ret;
265 }
266 
267 static int sun4i_csi_remove(struct platform_device *pdev)
268 {
269 	struct sun4i_csi *csi = platform_get_drvdata(pdev);
270 
271 	v4l2_async_notifier_unregister(&csi->notifier);
272 	v4l2_async_notifier_cleanup(&csi->notifier);
273 	vb2_video_unregister_device(&csi->vdev);
274 	media_device_unregister(&csi->mdev);
275 	sun4i_csi_dma_unregister(csi);
276 	media_device_cleanup(&csi->mdev);
277 
278 	return 0;
279 }
280 
281 static const struct sun4i_csi_traits sun4i_a10_csi1_traits = {
282 	.channels = 1,
283 	.max_width = 24,
284 	.has_isp = false,
285 };
286 
287 static const struct sun4i_csi_traits sun7i_a20_csi0_traits = {
288 	.channels = 4,
289 	.max_width = 16,
290 	.has_isp = true,
291 };
292 
293 static const struct of_device_id sun4i_csi_of_match[] = {
294 	{ .compatible = "allwinner,sun4i-a10-csi1", .data = &sun4i_a10_csi1_traits },
295 	{ .compatible = "allwinner,sun7i-a20-csi0", .data = &sun7i_a20_csi0_traits },
296 	{ /* Sentinel */ }
297 };
298 MODULE_DEVICE_TABLE(of, sun4i_csi_of_match);
299 
300 static int __maybe_unused sun4i_csi_runtime_resume(struct device *dev)
301 {
302 	struct sun4i_csi *csi = dev_get_drvdata(dev);
303 
304 	reset_control_deassert(csi->rst);
305 	clk_prepare_enable(csi->bus_clk);
306 	clk_prepare_enable(csi->ram_clk);
307 	clk_set_rate(csi->isp_clk, 80000000);
308 	clk_prepare_enable(csi->isp_clk);
309 
310 	writel(1, csi->regs + CSI_EN_REG);
311 
312 	return 0;
313 }
314 
315 static int __maybe_unused sun4i_csi_runtime_suspend(struct device *dev)
316 {
317 	struct sun4i_csi *csi = dev_get_drvdata(dev);
318 
319 	clk_disable_unprepare(csi->isp_clk);
320 	clk_disable_unprepare(csi->ram_clk);
321 	clk_disable_unprepare(csi->bus_clk);
322 
323 	reset_control_assert(csi->rst);
324 
325 	return 0;
326 }
327 
328 static const struct dev_pm_ops sun4i_csi_pm_ops = {
329 	SET_RUNTIME_PM_OPS(sun4i_csi_runtime_suspend,
330 			   sun4i_csi_runtime_resume,
331 			   NULL)
332 };
333 
334 static struct platform_driver sun4i_csi_driver = {
335 	.probe	= sun4i_csi_probe,
336 	.remove	= sun4i_csi_remove,
337 	.driver	= {
338 		.name		= "sun4i-csi",
339 		.of_match_table	= sun4i_csi_of_match,
340 		.pm		= &sun4i_csi_pm_ops,
341 	},
342 };
343 module_platform_driver(sun4i_csi_driver);
344 
345 MODULE_DESCRIPTION("Allwinner A10 Camera Sensor Interface driver");
346 MODULE_AUTHOR("Maxime Ripard <mripard@kernel.org>");
347 MODULE_LICENSE("GPL");
348