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_graph.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/reset.h>
19 #include <linux/videodev2.h>
20 
21 #include <media/v4l2-dev.h>
22 #include <media/v4l2-device.h>
23 #include <media/v4l2-fwnode.h>
24 #include <media/v4l2-ioctl.h>
25 #include <media/v4l2-mediabus.h>
26 
27 #include <media/videobuf2-core.h>
28 #include <media/videobuf2-dma-contig.h>
29 
30 #include "sun4i_csi.h"
31 
32 struct sun4i_csi_traits {
33 	unsigned int channels;
34 	unsigned int max_width;
35 	bool has_isp;
36 };
37 
38 static const struct media_entity_operations sun4i_csi_video_entity_ops = {
39 	.link_validate = v4l2_subdev_link_validate,
40 };
41 
42 static const struct media_entity_operations sun4i_csi_subdev_entity_ops = {
43 	.link_validate = v4l2_subdev_link_validate,
44 };
45 
46 static int sun4i_csi_notify_bound(struct v4l2_async_notifier *notifier,
47 				  struct v4l2_subdev *subdev,
48 				  struct v4l2_async_connection *asd)
49 {
50 	struct sun4i_csi *csi = container_of(notifier, struct sun4i_csi,
51 					     notifier);
52 
53 	csi->src_subdev = subdev;
54 	csi->src_pad = media_entity_get_fwnode_pad(&subdev->entity,
55 						   subdev->fwnode,
56 						   MEDIA_PAD_FL_SOURCE);
57 	if (csi->src_pad < 0) {
58 		dev_err(csi->dev, "Couldn't find output pad for subdev %s\n",
59 			subdev->name);
60 		return csi->src_pad;
61 	}
62 
63 	dev_dbg(csi->dev, "Bound %s pad: %d\n", subdev->name, csi->src_pad);
64 	return 0;
65 }
66 
67 static int sun4i_csi_notify_complete(struct v4l2_async_notifier *notifier)
68 {
69 	struct sun4i_csi *csi = container_of(notifier, struct sun4i_csi,
70 					     notifier);
71 	struct v4l2_subdev *subdev = &csi->subdev;
72 	struct video_device *vdev = &csi->vdev;
73 	int ret;
74 
75 	ret = v4l2_device_register_subdev(&csi->v4l, subdev);
76 	if (ret < 0)
77 		return ret;
78 
79 	ret = sun4i_csi_v4l2_register(csi);
80 	if (ret < 0)
81 		return ret;
82 
83 	ret = media_device_register(&csi->mdev);
84 	if (ret)
85 		return ret;
86 
87 	/* Create link from subdev to main device */
88 	ret = media_create_pad_link(&subdev->entity, CSI_SUBDEV_SOURCE,
89 				    &vdev->entity, 0,
90 				    MEDIA_LNK_FL_ENABLED |
91 				    MEDIA_LNK_FL_IMMUTABLE);
92 	if (ret)
93 		goto err_clean_media;
94 
95 	ret = media_create_pad_link(&csi->src_subdev->entity, csi->src_pad,
96 				    &subdev->entity, CSI_SUBDEV_SINK,
97 				    MEDIA_LNK_FL_ENABLED |
98 				    MEDIA_LNK_FL_IMMUTABLE);
99 	if (ret)
100 		goto err_clean_media;
101 
102 	ret = v4l2_device_register_subdev_nodes(&csi->v4l);
103 	if (ret < 0)
104 		goto err_clean_media;
105 
106 	return 0;
107 
108 err_clean_media:
109 	media_device_unregister(&csi->mdev);
110 
111 	return ret;
112 }
113 
114 static const struct v4l2_async_notifier_operations sun4i_csi_notify_ops = {
115 	.bound		= sun4i_csi_notify_bound,
116 	.complete	= sun4i_csi_notify_complete,
117 };
118 
119 static int sun4i_csi_notifier_init(struct sun4i_csi *csi)
120 {
121 	struct v4l2_fwnode_endpoint vep = {
122 		.bus_type = V4L2_MBUS_PARALLEL,
123 	};
124 	struct v4l2_async_connection *asd;
125 	struct fwnode_handle *ep;
126 	int ret;
127 
128 	v4l2_async_nf_init(&csi->notifier, &csi->v4l);
129 
130 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi->dev), 0, 0,
131 					     FWNODE_GRAPH_ENDPOINT_NEXT);
132 	if (!ep)
133 		return -EINVAL;
134 
135 	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
136 	if (ret)
137 		goto out;
138 
139 	csi->bus = vep.bus.parallel;
140 
141 	asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, ep,
142 					      struct v4l2_async_connection);
143 	if (IS_ERR(asd)) {
144 		ret = PTR_ERR(asd);
145 		goto out;
146 	}
147 
148 	csi->notifier.ops = &sun4i_csi_notify_ops;
149 
150 out:
151 	fwnode_handle_put(ep);
152 	return ret;
153 }
154 
155 static int sun4i_csi_probe(struct platform_device *pdev)
156 {
157 	struct v4l2_subdev *subdev;
158 	struct video_device *vdev;
159 	struct sun4i_csi *csi;
160 	int ret;
161 	int irq;
162 
163 	csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
164 	if (!csi)
165 		return -ENOMEM;
166 	platform_set_drvdata(pdev, csi);
167 	csi->dev = &pdev->dev;
168 	subdev = &csi->subdev;
169 	vdev = &csi->vdev;
170 
171 	csi->traits = of_device_get_match_data(&pdev->dev);
172 	if (!csi->traits)
173 		return -EINVAL;
174 
175 	csi->mdev.dev = csi->dev;
176 	strscpy(csi->mdev.model, "Allwinner Video Capture Device",
177 		sizeof(csi->mdev.model));
178 	csi->mdev.hw_revision = 0;
179 	media_device_init(&csi->mdev);
180 	csi->v4l.mdev = &csi->mdev;
181 
182 	csi->regs = devm_platform_ioremap_resource(pdev, 0);
183 	if (IS_ERR(csi->regs))
184 		return PTR_ERR(csi->regs);
185 
186 	irq = platform_get_irq(pdev, 0);
187 	if (irq < 0)
188 		return irq;
189 
190 	csi->bus_clk = devm_clk_get(&pdev->dev, "bus");
191 	if (IS_ERR(csi->bus_clk)) {
192 		dev_err(&pdev->dev, "Couldn't get our bus clock\n");
193 		return PTR_ERR(csi->bus_clk);
194 	}
195 
196 	if (csi->traits->has_isp) {
197 		csi->isp_clk = devm_clk_get(&pdev->dev, "isp");
198 		if (IS_ERR(csi->isp_clk)) {
199 			dev_err(&pdev->dev, "Couldn't get our ISP clock\n");
200 			return PTR_ERR(csi->isp_clk);
201 		}
202 	}
203 
204 	csi->ram_clk = devm_clk_get(&pdev->dev, "ram");
205 	if (IS_ERR(csi->ram_clk)) {
206 		dev_err(&pdev->dev, "Couldn't get our ram clock\n");
207 		return PTR_ERR(csi->ram_clk);
208 	}
209 
210 	csi->rst = devm_reset_control_get(&pdev->dev, NULL);
211 	if (IS_ERR(csi->rst)) {
212 		dev_err(&pdev->dev, "Couldn't get our reset line\n");
213 		return PTR_ERR(csi->rst);
214 	}
215 
216 	/* Initialize subdev */
217 	v4l2_subdev_init(subdev, &sun4i_csi_subdev_ops);
218 	subdev->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
219 	subdev->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
220 	subdev->entity.ops = &sun4i_csi_subdev_entity_ops;
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_nf_register(&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 void sun4i_csi_remove(struct platform_device *pdev)
268 {
269 	struct sun4i_csi *csi = platform_get_drvdata(pdev);
270 
271 	pm_runtime_disable(&pdev->dev);
272 	v4l2_async_nf_unregister(&csi->notifier);
273 	v4l2_async_nf_cleanup(&csi->notifier);
274 	vb2_video_unregister_device(&csi->vdev);
275 	media_device_unregister(&csi->mdev);
276 	sun4i_csi_dma_unregister(csi);
277 	media_device_cleanup(&csi->mdev);
278 }
279 
280 static const struct sun4i_csi_traits sun4i_a10_csi1_traits = {
281 	.channels = 1,
282 	.max_width = 24,
283 	.has_isp = false,
284 };
285 
286 static const struct sun4i_csi_traits sun7i_a20_csi0_traits = {
287 	.channels = 4,
288 	.max_width = 16,
289 	.has_isp = true,
290 };
291 
292 static const struct of_device_id sun4i_csi_of_match[] = {
293 	{ .compatible = "allwinner,sun4i-a10-csi1", .data = &sun4i_a10_csi1_traits },
294 	{ .compatible = "allwinner,sun7i-a20-csi0", .data = &sun7i_a20_csi0_traits },
295 	{ /* Sentinel */ }
296 };
297 MODULE_DEVICE_TABLE(of, sun4i_csi_of_match);
298 
299 static int __maybe_unused sun4i_csi_runtime_resume(struct device *dev)
300 {
301 	struct sun4i_csi *csi = dev_get_drvdata(dev);
302 
303 	reset_control_deassert(csi->rst);
304 	clk_prepare_enable(csi->bus_clk);
305 	clk_prepare_enable(csi->ram_clk);
306 	clk_set_rate(csi->isp_clk, 80000000);
307 	clk_prepare_enable(csi->isp_clk);
308 
309 	writel(1, csi->regs + CSI_EN_REG);
310 
311 	return 0;
312 }
313 
314 static int __maybe_unused sun4i_csi_runtime_suspend(struct device *dev)
315 {
316 	struct sun4i_csi *csi = dev_get_drvdata(dev);
317 
318 	clk_disable_unprepare(csi->isp_clk);
319 	clk_disable_unprepare(csi->ram_clk);
320 	clk_disable_unprepare(csi->bus_clk);
321 
322 	reset_control_assert(csi->rst);
323 
324 	return 0;
325 }
326 
327 static const struct dev_pm_ops sun4i_csi_pm_ops = {
328 	SET_RUNTIME_PM_OPS(sun4i_csi_runtime_suspend,
329 			   sun4i_csi_runtime_resume,
330 			   NULL)
331 };
332 
333 static struct platform_driver sun4i_csi_driver = {
334 	.probe	= sun4i_csi_probe,
335 	.remove_new = sun4i_csi_remove,
336 	.driver	= {
337 		.name		= "sun4i-csi",
338 		.of_match_table	= sun4i_csi_of_match,
339 		.pm		= &sun4i_csi_pm_ops,
340 	},
341 };
342 module_platform_driver(sun4i_csi_driver);
343 
344 MODULE_DESCRIPTION("Allwinner A10 Camera Sensor Interface driver");
345 MODULE_AUTHOR("Maxime Ripard <mripard@kernel.org>");
346 MODULE_LICENSE("GPL");
347