xref: /linux/drivers/media/platform/marvell/mmp-driver.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Support for the camera device found on Marvell MMP processors; known
4  * to work with the Armada 610 as used in the OLPC 1.75 system.
5  *
6  * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
7  * Copyright 2018 Lubomir Rintel <lkundrak@v3.sk>
8  */
9 
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/spinlock.h>
15 #include <linux/slab.h>
16 #include <linux/videodev2.h>
17 #include <media/v4l2-device.h>
18 #include <linux/platform_data/media/mmp-camera.h>
19 #include <linux/device.h>
20 #include <linux/of.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/io.h>
25 #include <linux/list.h>
26 #include <linux/pm.h>
27 #include <linux/clk.h>
28 
29 #include "mcam-core.h"
30 
31 MODULE_ALIAS("platform:mmp-camera");
32 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
33 MODULE_DESCRIPTION("Support for the camera device found on Marvell MMP processors");
34 MODULE_LICENSE("GPL");
35 
36 static char *mcam_clks[] = {"axi", "func", "phy"};
37 
38 struct mmp_camera {
39 	struct platform_device *pdev;
40 	struct mcam_camera mcam;
41 	struct list_head devlist;
42 	struct clk *mipi_clk;
43 	int irq;
44 };
45 
46 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
47 {
48 	return container_of(mcam, struct mmp_camera, mcam);
49 }
50 
51 /*
52  * calc the dphy register values
53  * There are three dphy registers being used.
54  * dphy[0] - CSI2_DPHY3
55  * dphy[1] - CSI2_DPHY5
56  * dphy[2] - CSI2_DPHY6
57  * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
58  * or be calculated dynamically
59  */
60 static void mmpcam_calc_dphy(struct mcam_camera *mcam)
61 {
62 	struct mmp_camera *cam = mcam_to_cam(mcam);
63 	struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
64 	struct device *dev = &cam->pdev->dev;
65 	unsigned long tx_clk_esc;
66 
67 	/*
68 	 * If CSI2_DPHY3 is calculated dynamically,
69 	 * pdata->lane_clk should be already set
70 	 * either in the board driver statically
71 	 * or in the sensor driver dynamically.
72 	 */
73 	/*
74 	 * dphy[0] - CSI2_DPHY3:
75 	 *  bit 0 ~ bit 7: HS Term Enable.
76 	 *   defines the time that the DPHY
77 	 *   wait before enabling the data
78 	 *   lane termination after detecting
79 	 *   that the sensor has driven the data
80 	 *   lanes to the LP00 bridge state.
81 	 *   The value is calculated by:
82 	 *   (Max T(D_TERM_EN)/Period(DDR)) - 1
83 	 *  bit 8 ~ bit 15: HS_SETTLE
84 	 *   Time interval during which the HS
85 	 *   receiver shall ignore any Data Lane
86 	 *   HS transitions.
87 	 *   The value has been calibrated on
88 	 *   different boards. It seems to work well.
89 	 *
90 	 *  More detail please refer
91 	 *  MIPI Alliance Spectification for D-PHY
92 	 *  document for explanation of HS-SETTLE
93 	 *  and D-TERM-EN.
94 	 */
95 	switch (pdata->dphy3_algo) {
96 	case DPHY3_ALGO_PXA910:
97 		/*
98 		 * Calculate CSI2_DPHY3 algo for PXA910
99 		 */
100 		pdata->dphy[0] =
101 			(((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
102 			| (1 + pdata->lane_clk * 35 / 1000);
103 		break;
104 	case DPHY3_ALGO_PXA2128:
105 		/*
106 		 * Calculate CSI2_DPHY3 algo for PXA2128
107 		 */
108 		pdata->dphy[0] =
109 			(((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
110 			| (1 + pdata->lane_clk * 35 / 1000);
111 		break;
112 	default:
113 		/*
114 		 * Use default CSI2_DPHY3 value for PXA688/PXA988
115 		 */
116 		dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
117 	}
118 
119 	/*
120 	 * mipi_clk will never be changed, it is a fixed value on MMP
121 	 */
122 	if (IS_ERR(cam->mipi_clk))
123 		return;
124 
125 	/* get the escape clk, this is hard coded */
126 	clk_prepare_enable(cam->mipi_clk);
127 	tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
128 	clk_disable_unprepare(cam->mipi_clk);
129 	/*
130 	 * dphy[2] - CSI2_DPHY6:
131 	 * bit 0 ~ bit 7: CK Term Enable
132 	 *  Time for the Clock Lane receiver to enable the HS line
133 	 *  termination. The value is calculated similarly with
134 	 *  HS Term Enable
135 	 * bit 8 ~ bit 15: CK Settle
136 	 *  Time interval during which the HS receiver shall ignore
137 	 *  any Clock Lane HS transitions.
138 	 *  The value is calibrated on the boards.
139 	 */
140 	pdata->dphy[2] =
141 		((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
142 		| (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
143 
144 	dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
145 		pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
146 }
147 
148 static irqreturn_t mmpcam_irq(int irq, void *data)
149 {
150 	struct mcam_camera *mcam = data;
151 	unsigned int irqs, handled;
152 
153 	spin_lock(&mcam->dev_lock);
154 	irqs = mcam_reg_read(mcam, REG_IRQSTAT);
155 	handled = mccic_irq(mcam, irqs);
156 	spin_unlock(&mcam->dev_lock);
157 	return IRQ_RETVAL(handled);
158 }
159 
160 static void mcam_init_clk(struct mcam_camera *mcam)
161 {
162 	unsigned int i;
163 
164 	for (i = 0; i < NR_MCAM_CLK; i++) {
165 		if (mcam_clks[i] != NULL) {
166 			/* Some clks are not necessary on some boards
167 			 * We still try to run even it fails getting clk
168 			 */
169 			mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
170 			if (IS_ERR(mcam->clk[i]))
171 				dev_warn(mcam->dev, "Could not get clk: %s\n",
172 						mcam_clks[i]);
173 		}
174 	}
175 }
176 
177 static int mmpcam_probe(struct platform_device *pdev)
178 {
179 	struct mmp_camera *cam;
180 	struct mcam_camera *mcam;
181 	struct resource *res;
182 	struct fwnode_handle *ep;
183 	struct mmp_camera_platform_data *pdata;
184 	struct v4l2_async_connection *asd;
185 	int ret;
186 
187 	cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
188 	if (cam == NULL)
189 		return -ENOMEM;
190 	platform_set_drvdata(pdev, cam);
191 	cam->pdev = pdev;
192 	INIT_LIST_HEAD(&cam->devlist);
193 
194 	mcam = &cam->mcam;
195 	mcam->calc_dphy = mmpcam_calc_dphy;
196 	mcam->dev = &pdev->dev;
197 	pdata = pdev->dev.platform_data;
198 	if (pdata) {
199 		mcam->mclk_src = pdata->mclk_src;
200 		mcam->mclk_div = pdata->mclk_div;
201 		mcam->bus_type = pdata->bus_type;
202 		mcam->dphy = pdata->dphy;
203 		mcam->lane = pdata->lane;
204 	} else {
205 		/*
206 		 * These are values that used to be hardcoded in mcam-core and
207 		 * work well on a OLPC XO 1.75 with a parallel bus sensor.
208 		 * If it turns out other setups make sense, the values should
209 		 * be obtained from the device tree.
210 		 */
211 		mcam->mclk_src = 3;
212 		mcam->mclk_div = 2;
213 	}
214 	if (mcam->bus_type == V4L2_MBUS_CSI2_DPHY) {
215 		cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
216 		if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
217 			return PTR_ERR(cam->mipi_clk);
218 	}
219 	mcam->mipi_enabled = false;
220 	mcam->chip_id = MCAM_ARMADA610;
221 	mcam->buffer_mode = B_DMA_sg;
222 	strscpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
223 	spin_lock_init(&mcam->dev_lock);
224 	/*
225 	 * Get our I/O memory.
226 	 */
227 	mcam->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
228 	if (IS_ERR(mcam->regs))
229 		return PTR_ERR(mcam->regs);
230 	mcam->regs_size = resource_size(res);
231 
232 	mcam_init_clk(mcam);
233 
234 	/*
235 	 * Create a match of the sensor against its OF node.
236 	 */
237 	ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(pdev->dev.of_node),
238 					    NULL);
239 	if (!ep)
240 		return -ENODEV;
241 
242 	v4l2_async_nf_init(&mcam->notifier, &mcam->v4l2_dev);
243 
244 	asd = v4l2_async_nf_add_fwnode_remote(&mcam->notifier, ep,
245 					      struct v4l2_async_connection);
246 	fwnode_handle_put(ep);
247 	if (IS_ERR(asd)) {
248 		ret = PTR_ERR(asd);
249 		goto out;
250 	}
251 
252 	/*
253 	 * Register the device with the core.
254 	 */
255 	ret = mccic_register(mcam);
256 	if (ret)
257 		goto out;
258 
259 	/*
260 	 * Add OF clock provider.
261 	 */
262 	ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get,
263 								mcam->mclk);
264 	if (ret) {
265 		dev_err(&pdev->dev, "can't add DT clock provider\n");
266 		goto out;
267 	}
268 
269 	/*
270 	 * Finally, set up our IRQ now that the core is ready to
271 	 * deal with it.
272 	 */
273 	ret = platform_get_irq(pdev, 0);
274 	if (ret < 0)
275 		goto out;
276 	cam->irq = ret;
277 	ret = devm_request_irq(&pdev->dev, cam->irq, mmpcam_irq, IRQF_SHARED,
278 					"mmp-camera", mcam);
279 	if (ret)
280 		goto out;
281 
282 	pm_runtime_enable(&pdev->dev);
283 	return 0;
284 out:
285 	mccic_shutdown(mcam);
286 
287 	return ret;
288 }
289 
290 static void mmpcam_remove(struct platform_device *pdev)
291 {
292 	struct mmp_camera *cam = platform_get_drvdata(pdev);
293 	struct mcam_camera *mcam = &cam->mcam;
294 
295 	mccic_shutdown(mcam);
296 	pm_runtime_force_suspend(mcam->dev);
297 }
298 
299 /*
300  * Suspend/resume support.
301  */
302 
303 static int __maybe_unused mmpcam_runtime_resume(struct device *dev)
304 {
305 	struct mmp_camera *cam = dev_get_drvdata(dev);
306 	struct mcam_camera *mcam = &cam->mcam;
307 	unsigned int i;
308 
309 	for (i = 0; i < NR_MCAM_CLK; i++) {
310 		if (!IS_ERR(mcam->clk[i]))
311 			clk_prepare_enable(mcam->clk[i]);
312 	}
313 
314 	return 0;
315 }
316 
317 static int __maybe_unused mmpcam_runtime_suspend(struct device *dev)
318 {
319 	struct mmp_camera *cam = dev_get_drvdata(dev);
320 	struct mcam_camera *mcam = &cam->mcam;
321 	int i;
322 
323 	for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
324 		if (!IS_ERR(mcam->clk[i]))
325 			clk_disable_unprepare(mcam->clk[i]);
326 	}
327 
328 	return 0;
329 }
330 
331 static int __maybe_unused mmpcam_suspend(struct device *dev)
332 {
333 	struct mmp_camera *cam = dev_get_drvdata(dev);
334 
335 	if (!pm_runtime_suspended(dev))
336 		mccic_suspend(&cam->mcam);
337 	return 0;
338 }
339 
340 static int __maybe_unused mmpcam_resume(struct device *dev)
341 {
342 	struct mmp_camera *cam = dev_get_drvdata(dev);
343 
344 	if (!pm_runtime_suspended(dev))
345 		return mccic_resume(&cam->mcam);
346 	return 0;
347 }
348 
349 static const struct dev_pm_ops mmpcam_pm_ops = {
350 	SET_RUNTIME_PM_OPS(mmpcam_runtime_suspend, mmpcam_runtime_resume, NULL)
351 	SET_SYSTEM_SLEEP_PM_OPS(mmpcam_suspend, mmpcam_resume)
352 };
353 
354 static const struct of_device_id mmpcam_of_match[] = {
355 	{ .compatible = "marvell,mmp2-ccic", },
356 	{},
357 };
358 MODULE_DEVICE_TABLE(of, mmpcam_of_match);
359 
360 static struct platform_driver mmpcam_driver = {
361 	.probe		= mmpcam_probe,
362 	.remove		= mmpcam_remove,
363 	.driver = {
364 		.name	= "mmp-camera",
365 		.of_match_table = mmpcam_of_match,
366 		.pm = &mmpcam_pm_ops,
367 	}
368 };
369 
370 module_platform_driver(mmpcam_driver);
371