1 /*
2  * Driver for the SH-Mobile MIPI CSI-2 unit
3  *
4  * Copyright (C) 2010, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/i2c.h>
13 #include <linux/io.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 #include <linux/videodev2.h>
18 #include <linux/module.h>
19 
20 #include <media/sh_mobile_ceu.h>
21 #include <media/sh_mobile_csi2.h>
22 #include <media/soc_camera.h>
23 #include <media/soc_mediabus.h>
24 #include <media/v4l2-common.h>
25 #include <media/v4l2-dev.h>
26 #include <media/v4l2-device.h>
27 #include <media/v4l2-mediabus.h>
28 #include <media/v4l2-subdev.h>
29 
30 #define SH_CSI2_TREF	0x00
31 #define SH_CSI2_SRST	0x04
32 #define SH_CSI2_PHYCNT	0x08
33 #define SH_CSI2_CHKSUM	0x0C
34 #define SH_CSI2_VCDT	0x10
35 
36 struct sh_csi2 {
37 	struct v4l2_subdev		subdev;
38 	struct list_head		list;
39 	unsigned int			irq;
40 	unsigned long			mipi_flags;
41 	void __iomem			*base;
42 	struct platform_device		*pdev;
43 	struct sh_csi2_client_config	*client;
44 };
45 
sh_csi2_try_fmt(struct v4l2_subdev * sd,struct v4l2_mbus_framefmt * mf)46 static int sh_csi2_try_fmt(struct v4l2_subdev *sd,
47 			   struct v4l2_mbus_framefmt *mf)
48 {
49 	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
50 	struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
51 
52 	if (mf->width > 8188)
53 		mf->width = 8188;
54 	else if (mf->width & 1)
55 		mf->width &= ~1;
56 
57 	switch (pdata->type) {
58 	case SH_CSI2C:
59 		switch (mf->code) {
60 		case V4L2_MBUS_FMT_UYVY8_2X8:		/* YUV422 */
61 		case V4L2_MBUS_FMT_YUYV8_1_5X8:		/* YUV420 */
62 		case V4L2_MBUS_FMT_Y8_1X8:		/* RAW8 */
63 		case V4L2_MBUS_FMT_SBGGR8_1X8:
64 		case V4L2_MBUS_FMT_SGRBG8_1X8:
65 			break;
66 		default:
67 			/* All MIPI CSI-2 devices must support one of primary formats */
68 			mf->code = V4L2_MBUS_FMT_YUYV8_2X8;
69 		}
70 		break;
71 	case SH_CSI2I:
72 		switch (mf->code) {
73 		case V4L2_MBUS_FMT_Y8_1X8:		/* RAW8 */
74 		case V4L2_MBUS_FMT_SBGGR8_1X8:
75 		case V4L2_MBUS_FMT_SGRBG8_1X8:
76 		case V4L2_MBUS_FMT_SBGGR10_1X10:	/* RAW10 */
77 		case V4L2_MBUS_FMT_SBGGR12_1X12:	/* RAW12 */
78 			break;
79 		default:
80 			/* All MIPI CSI-2 devices must support one of primary formats */
81 			mf->code = V4L2_MBUS_FMT_SBGGR8_1X8;
82 		}
83 		break;
84 	}
85 
86 	return 0;
87 }
88 
89 /*
90  * We have done our best in try_fmt to try and tell the sensor, which formats
91  * we support. If now the configuration is unsuitable for us we can only
92  * error out.
93  */
sh_csi2_s_fmt(struct v4l2_subdev * sd,struct v4l2_mbus_framefmt * mf)94 static int sh_csi2_s_fmt(struct v4l2_subdev *sd,
95 			 struct v4l2_mbus_framefmt *mf)
96 {
97 	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
98 	u32 tmp = (priv->client->channel & 3) << 8;
99 
100 	dev_dbg(sd->v4l2_dev->dev, "%s(%u)\n", __func__, mf->code);
101 	if (mf->width > 8188 || mf->width & 1)
102 		return -EINVAL;
103 
104 	switch (mf->code) {
105 	case V4L2_MBUS_FMT_UYVY8_2X8:
106 		tmp |= 0x1e;	/* YUV422 8 bit */
107 		break;
108 	case V4L2_MBUS_FMT_YUYV8_1_5X8:
109 		tmp |= 0x18;	/* YUV420 8 bit */
110 		break;
111 	case V4L2_MBUS_FMT_RGB555_2X8_PADHI_BE:
112 		tmp |= 0x21;	/* RGB555 */
113 		break;
114 	case V4L2_MBUS_FMT_RGB565_2X8_BE:
115 		tmp |= 0x22;	/* RGB565 */
116 		break;
117 	case V4L2_MBUS_FMT_Y8_1X8:
118 	case V4L2_MBUS_FMT_SBGGR8_1X8:
119 	case V4L2_MBUS_FMT_SGRBG8_1X8:
120 		tmp |= 0x2a;	/* RAW8 */
121 		break;
122 	default:
123 		return -EINVAL;
124 	}
125 
126 	iowrite32(tmp, priv->base + SH_CSI2_VCDT);
127 
128 	return 0;
129 }
130 
sh_csi2_g_mbus_config(struct v4l2_subdev * sd,struct v4l2_mbus_config * cfg)131 static int sh_csi2_g_mbus_config(struct v4l2_subdev *sd,
132 				 struct v4l2_mbus_config *cfg)
133 {
134 	cfg->flags = V4L2_MBUS_PCLK_SAMPLE_RISING |
135 		V4L2_MBUS_HSYNC_ACTIVE_HIGH | V4L2_MBUS_VSYNC_ACTIVE_HIGH |
136 		V4L2_MBUS_MASTER | V4L2_MBUS_DATA_ACTIVE_HIGH;
137 	cfg->type = V4L2_MBUS_PARALLEL;
138 
139 	return 0;
140 }
141 
sh_csi2_s_mbus_config(struct v4l2_subdev * sd,const struct v4l2_mbus_config * cfg)142 static int sh_csi2_s_mbus_config(struct v4l2_subdev *sd,
143 				 const struct v4l2_mbus_config *cfg)
144 {
145 	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
146 	struct soc_camera_device *icd = v4l2_get_subdev_hostdata(sd);
147 	struct v4l2_subdev *client_sd = soc_camera_to_subdev(icd);
148 	struct v4l2_mbus_config client_cfg = {.type = V4L2_MBUS_CSI2,
149 					      .flags = priv->mipi_flags};
150 
151 	return v4l2_subdev_call(client_sd, video, s_mbus_config, &client_cfg);
152 }
153 
154 static struct v4l2_subdev_video_ops sh_csi2_subdev_video_ops = {
155 	.s_mbus_fmt	= sh_csi2_s_fmt,
156 	.try_mbus_fmt	= sh_csi2_try_fmt,
157 	.g_mbus_config	= sh_csi2_g_mbus_config,
158 	.s_mbus_config	= sh_csi2_s_mbus_config,
159 };
160 
sh_csi2_hwinit(struct sh_csi2 * priv)161 static void sh_csi2_hwinit(struct sh_csi2 *priv)
162 {
163 	struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
164 	__u32 tmp = 0x10; /* Enable MIPI CSI clock lane */
165 
166 	/* Reflect registers immediately */
167 	iowrite32(0x00000001, priv->base + SH_CSI2_TREF);
168 	/* reset CSI2 harware */
169 	iowrite32(0x00000001, priv->base + SH_CSI2_SRST);
170 	udelay(5);
171 	iowrite32(0x00000000, priv->base + SH_CSI2_SRST);
172 
173 	switch (pdata->type) {
174 	case SH_CSI2C:
175 		if (priv->client->lanes == 1)
176 			tmp |= 1;
177 		else
178 			/* Default - both lanes */
179 			tmp |= 3;
180 		break;
181 	case SH_CSI2I:
182 		if (!priv->client->lanes || priv->client->lanes > 4)
183 			/* Default - all 4 lanes */
184 			tmp |= 0xf;
185 		else
186 			tmp |= (1 << priv->client->lanes) - 1;
187 	}
188 
189 	if (priv->client->phy == SH_CSI2_PHY_MAIN)
190 		tmp |= 0x8000;
191 
192 	iowrite32(tmp, priv->base + SH_CSI2_PHYCNT);
193 
194 	tmp = 0;
195 	if (pdata->flags & SH_CSI2_ECC)
196 		tmp |= 2;
197 	if (pdata->flags & SH_CSI2_CRC)
198 		tmp |= 1;
199 	iowrite32(tmp, priv->base + SH_CSI2_CHKSUM);
200 }
201 
sh_csi2_client_connect(struct sh_csi2 * priv)202 static int sh_csi2_client_connect(struct sh_csi2 *priv)
203 {
204 	struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
205 	struct soc_camera_device *icd = v4l2_get_subdev_hostdata(&priv->subdev);
206 	struct v4l2_subdev *client_sd = soc_camera_to_subdev(icd);
207 	struct device *dev = v4l2_get_subdevdata(&priv->subdev);
208 	struct v4l2_mbus_config cfg;
209 	unsigned long common_flags, csi2_flags;
210 	int i, ret;
211 
212 	if (priv->client)
213 		return -EBUSY;
214 
215 	for (i = 0; i < pdata->num_clients; i++)
216 		if (&pdata->clients[i].pdev->dev == icd->pdev)
217 			break;
218 
219 	dev_dbg(dev, "%s(%p): found #%d\n", __func__, dev, i);
220 
221 	if (i == pdata->num_clients)
222 		return -ENODEV;
223 
224 	/* Check if we can support this camera */
225 	csi2_flags = V4L2_MBUS_CSI2_CONTINUOUS_CLOCK | V4L2_MBUS_CSI2_1_LANE;
226 
227 	switch (pdata->type) {
228 	case SH_CSI2C:
229 		if (pdata->clients[i].lanes != 1)
230 			csi2_flags |= V4L2_MBUS_CSI2_2_LANE;
231 		break;
232 	case SH_CSI2I:
233 		switch (pdata->clients[i].lanes) {
234 		default:
235 			csi2_flags |= V4L2_MBUS_CSI2_4_LANE;
236 		case 3:
237 			csi2_flags |= V4L2_MBUS_CSI2_3_LANE;
238 		case 2:
239 			csi2_flags |= V4L2_MBUS_CSI2_2_LANE;
240 		}
241 	}
242 
243 	cfg.type = V4L2_MBUS_CSI2;
244 	ret = v4l2_subdev_call(client_sd, video, g_mbus_config, &cfg);
245 	if (ret == -ENOIOCTLCMD)
246 		common_flags = csi2_flags;
247 	else if (!ret)
248 		common_flags = soc_mbus_config_compatible(&cfg,
249 							  csi2_flags);
250 	else
251 		common_flags = 0;
252 
253 	if (!common_flags)
254 		return -EINVAL;
255 
256 	/* All good: camera MIPI configuration supported */
257 	priv->mipi_flags = common_flags;
258 	priv->client = pdata->clients + i;
259 
260 	pm_runtime_get_sync(dev);
261 
262 	sh_csi2_hwinit(priv);
263 
264 	return 0;
265 }
266 
sh_csi2_client_disconnect(struct sh_csi2 * priv)267 static void sh_csi2_client_disconnect(struct sh_csi2 *priv)
268 {
269 	if (!priv->client)
270 		return;
271 
272 	priv->client = NULL;
273 
274 	pm_runtime_put(v4l2_get_subdevdata(&priv->subdev));
275 }
276 
sh_csi2_s_power(struct v4l2_subdev * sd,int on)277 static int sh_csi2_s_power(struct v4l2_subdev *sd, int on)
278 {
279 	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
280 
281 	if (on)
282 		return sh_csi2_client_connect(priv);
283 
284 	sh_csi2_client_disconnect(priv);
285 	return 0;
286 }
287 
288 static struct v4l2_subdev_core_ops sh_csi2_subdev_core_ops = {
289 	.s_power	= sh_csi2_s_power,
290 };
291 
292 static struct v4l2_subdev_ops sh_csi2_subdev_ops = {
293 	.core	= &sh_csi2_subdev_core_ops,
294 	.video	= &sh_csi2_subdev_video_ops,
295 };
296 
sh_csi2_probe(struct platform_device * pdev)297 static __devinit int sh_csi2_probe(struct platform_device *pdev)
298 {
299 	struct resource *res;
300 	unsigned int irq;
301 	int ret;
302 	struct sh_csi2 *priv;
303 	/* Platform data specify the PHY, lanes, ECC, CRC */
304 	struct sh_csi2_pdata *pdata = pdev->dev.platform_data;
305 
306 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
307 	/* Interrupt unused so far */
308 	irq = platform_get_irq(pdev, 0);
309 
310 	if (!res || (int)irq <= 0 || !pdata) {
311 		dev_err(&pdev->dev, "Not enough CSI2 platform resources.\n");
312 		return -ENODEV;
313 	}
314 
315 	/* TODO: Add support for CSI2I. Careful: different register layout! */
316 	if (pdata->type != SH_CSI2C) {
317 		dev_err(&pdev->dev, "Only CSI2C supported ATM.\n");
318 		return -EINVAL;
319 	}
320 
321 	priv = kzalloc(sizeof(struct sh_csi2), GFP_KERNEL);
322 	if (!priv)
323 		return -ENOMEM;
324 
325 	priv->irq = irq;
326 
327 	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
328 		dev_err(&pdev->dev, "CSI2 register region already claimed\n");
329 		ret = -EBUSY;
330 		goto ereqreg;
331 	}
332 
333 	priv->base = ioremap(res->start, resource_size(res));
334 	if (!priv->base) {
335 		ret = -ENXIO;
336 		dev_err(&pdev->dev, "Unable to ioremap CSI2 registers.\n");
337 		goto eremap;
338 	}
339 
340 	priv->pdev = pdev;
341 	platform_set_drvdata(pdev, priv);
342 
343 	v4l2_subdev_init(&priv->subdev, &sh_csi2_subdev_ops);
344 	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
345 
346 	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.mipi-csi",
347 		 dev_name(pdata->v4l2_dev->dev));
348 	ret = v4l2_device_register_subdev(pdata->v4l2_dev, &priv->subdev);
349 	dev_dbg(&pdev->dev, "%s(%p): ret(register_subdev) = %d\n", __func__, priv, ret);
350 	if (ret < 0)
351 		goto esdreg;
352 
353 	pm_runtime_enable(&pdev->dev);
354 
355 	dev_dbg(&pdev->dev, "CSI2 probed.\n");
356 
357 	return 0;
358 
359 esdreg:
360 	iounmap(priv->base);
361 eremap:
362 	release_mem_region(res->start, resource_size(res));
363 ereqreg:
364 	kfree(priv);
365 
366 	return ret;
367 }
368 
sh_csi2_remove(struct platform_device * pdev)369 static __devexit int sh_csi2_remove(struct platform_device *pdev)
370 {
371 	struct sh_csi2 *priv = platform_get_drvdata(pdev);
372 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
373 
374 	v4l2_device_unregister_subdev(&priv->subdev);
375 	pm_runtime_disable(&pdev->dev);
376 	iounmap(priv->base);
377 	release_mem_region(res->start, resource_size(res));
378 	platform_set_drvdata(pdev, NULL);
379 	kfree(priv);
380 
381 	return 0;
382 }
383 
384 static struct platform_driver __refdata sh_csi2_pdrv = {
385 	.remove	= __devexit_p(sh_csi2_remove),
386 	.probe	= sh_csi2_probe,
387 	.driver	= {
388 		.name	= "sh-mobile-csi2",
389 		.owner	= THIS_MODULE,
390 	},
391 };
392 
393 module_platform_driver(sh_csi2_pdrv);
394 
395 MODULE_DESCRIPTION("SH-Mobile MIPI CSI-2 driver");
396 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
397 MODULE_LICENSE("GPL v2");
398 MODULE_ALIAS("platform:sh-mobile-csi2");
399