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_LICENSE("GPL");
34
35 static char *mcam_clks[] = {"axi", "func", "phy"};
36
37 struct mmp_camera {
38 struct platform_device *pdev;
39 struct mcam_camera mcam;
40 struct list_head devlist;
41 struct clk *mipi_clk;
42 int irq;
43 };
44
mcam_to_cam(struct mcam_camera * mcam)45 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
46 {
47 return container_of(mcam, struct mmp_camera, mcam);
48 }
49
50 /*
51 * calc the dphy register values
52 * There are three dphy registers being used.
53 * dphy[0] - CSI2_DPHY3
54 * dphy[1] - CSI2_DPHY5
55 * dphy[2] - CSI2_DPHY6
56 * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
57 * or be calculated dynamically
58 */
mmpcam_calc_dphy(struct mcam_camera * mcam)59 static void mmpcam_calc_dphy(struct mcam_camera *mcam)
60 {
61 struct mmp_camera *cam = mcam_to_cam(mcam);
62 struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
63 struct device *dev = &cam->pdev->dev;
64 unsigned long tx_clk_esc;
65
66 /*
67 * If CSI2_DPHY3 is calculated dynamically,
68 * pdata->lane_clk should be already set
69 * either in the board driver statically
70 * or in the sensor driver dynamically.
71 */
72 /*
73 * dphy[0] - CSI2_DPHY3:
74 * bit 0 ~ bit 7: HS Term Enable.
75 * defines the time that the DPHY
76 * wait before enabling the data
77 * lane termination after detecting
78 * that the sensor has driven the data
79 * lanes to the LP00 bridge state.
80 * The value is calculated by:
81 * (Max T(D_TERM_EN)/Period(DDR)) - 1
82 * bit 8 ~ bit 15: HS_SETTLE
83 * Time interval during which the HS
84 * receiver shall ignore any Data Lane
85 * HS transitions.
86 * The value has been calibrated on
87 * different boards. It seems to work well.
88 *
89 * More detail please refer
90 * MIPI Alliance Spectification for D-PHY
91 * document for explanation of HS-SETTLE
92 * and D-TERM-EN.
93 */
94 switch (pdata->dphy3_algo) {
95 case DPHY3_ALGO_PXA910:
96 /*
97 * Calculate CSI2_DPHY3 algo for PXA910
98 */
99 pdata->dphy[0] =
100 (((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
101 | (1 + pdata->lane_clk * 35 / 1000);
102 break;
103 case DPHY3_ALGO_PXA2128:
104 /*
105 * Calculate CSI2_DPHY3 algo for PXA2128
106 */
107 pdata->dphy[0] =
108 (((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
109 | (1 + pdata->lane_clk * 35 / 1000);
110 break;
111 default:
112 /*
113 * Use default CSI2_DPHY3 value for PXA688/PXA988
114 */
115 dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
116 }
117
118 /*
119 * mipi_clk will never be changed, it is a fixed value on MMP
120 */
121 if (IS_ERR(cam->mipi_clk))
122 return;
123
124 /* get the escape clk, this is hard coded */
125 clk_prepare_enable(cam->mipi_clk);
126 tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
127 clk_disable_unprepare(cam->mipi_clk);
128 /*
129 * dphy[2] - CSI2_DPHY6:
130 * bit 0 ~ bit 7: CK Term Enable
131 * Time for the Clock Lane receiver to enable the HS line
132 * termination. The value is calculated similarly with
133 * HS Term Enable
134 * bit 8 ~ bit 15: CK Settle
135 * Time interval during which the HS receiver shall ignore
136 * any Clock Lane HS transitions.
137 * The value is calibrated on the boards.
138 */
139 pdata->dphy[2] =
140 ((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
141 | (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
142
143 dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
144 pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
145 }
146
mmpcam_irq(int irq,void * data)147 static irqreturn_t mmpcam_irq(int irq, void *data)
148 {
149 struct mcam_camera *mcam = data;
150 unsigned int irqs, handled;
151
152 spin_lock(&mcam->dev_lock);
153 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
154 handled = mccic_irq(mcam, irqs);
155 spin_unlock(&mcam->dev_lock);
156 return IRQ_RETVAL(handled);
157 }
158
mcam_init_clk(struct mcam_camera * mcam)159 static void mcam_init_clk(struct mcam_camera *mcam)
160 {
161 unsigned int i;
162
163 for (i = 0; i < NR_MCAM_CLK; i++) {
164 if (mcam_clks[i] != NULL) {
165 /* Some clks are not necessary on some boards
166 * We still try to run even it fails getting clk
167 */
168 mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
169 if (IS_ERR(mcam->clk[i]))
170 dev_warn(mcam->dev, "Could not get clk: %s\n",
171 mcam_clks[i]);
172 }
173 }
174 }
175
mmpcam_probe(struct platform_device * pdev)176 static int mmpcam_probe(struct platform_device *pdev)
177 {
178 struct mmp_camera *cam;
179 struct mcam_camera *mcam;
180 struct resource *res;
181 struct fwnode_handle *ep;
182 struct mmp_camera_platform_data *pdata;
183 struct v4l2_async_subdev *asd;
184 int ret;
185
186 cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
187 if (cam == NULL)
188 return -ENOMEM;
189 platform_set_drvdata(pdev, cam);
190 cam->pdev = pdev;
191 INIT_LIST_HEAD(&cam->devlist);
192
193 mcam = &cam->mcam;
194 mcam->calc_dphy = mmpcam_calc_dphy;
195 mcam->dev = &pdev->dev;
196 pdata = pdev->dev.platform_data;
197 if (pdata) {
198 mcam->mclk_src = pdata->mclk_src;
199 mcam->mclk_div = pdata->mclk_div;
200 mcam->bus_type = pdata->bus_type;
201 mcam->dphy = pdata->dphy;
202 mcam->lane = pdata->lane;
203 } else {
204 /*
205 * These are values that used to be hardcoded in mcam-core and
206 * work well on a OLPC XO 1.75 with a parallel bus sensor.
207 * If it turns out other setups make sense, the values should
208 * be obtained from the device tree.
209 */
210 mcam->mclk_src = 3;
211 mcam->mclk_div = 2;
212 }
213 if (mcam->bus_type == V4L2_MBUS_CSI2_DPHY) {
214 cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
215 if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
216 return PTR_ERR(cam->mipi_clk);
217 }
218 mcam->mipi_enabled = false;
219 mcam->chip_id = MCAM_ARMADA610;
220 mcam->buffer_mode = B_DMA_sg;
221 strscpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
222 spin_lock_init(&mcam->dev_lock);
223 /*
224 * Get our I/O memory.
225 */
226 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
227 mcam->regs = devm_ioremap_resource(&pdev->dev, 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);
243
244 asd = v4l2_async_nf_add_fwnode_remote(&mcam->notifier, ep,
245 struct v4l2_async_subdev);
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 return ret;
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
mmpcam_remove(struct mmp_camera * cam)291 static int mmpcam_remove(struct mmp_camera *cam)
292 {
293 struct mcam_camera *mcam = &cam->mcam;
294
295 mccic_shutdown(mcam);
296 pm_runtime_force_suspend(mcam->dev);
297 return 0;
298 }
299
mmpcam_platform_remove(struct platform_device * pdev)300 static int mmpcam_platform_remove(struct platform_device *pdev)
301 {
302 struct mmp_camera *cam = platform_get_drvdata(pdev);
303
304 if (cam == NULL)
305 return -ENODEV;
306 return mmpcam_remove(cam);
307 }
308
309 /*
310 * Suspend/resume support.
311 */
312
mmpcam_runtime_resume(struct device * dev)313 static int __maybe_unused mmpcam_runtime_resume(struct device *dev)
314 {
315 struct mmp_camera *cam = dev_get_drvdata(dev);
316 struct mcam_camera *mcam = &cam->mcam;
317 unsigned int i;
318
319 for (i = 0; i < NR_MCAM_CLK; i++) {
320 if (!IS_ERR(mcam->clk[i]))
321 clk_prepare_enable(mcam->clk[i]);
322 }
323
324 return 0;
325 }
326
mmpcam_runtime_suspend(struct device * dev)327 static int __maybe_unused mmpcam_runtime_suspend(struct device *dev)
328 {
329 struct mmp_camera *cam = dev_get_drvdata(dev);
330 struct mcam_camera *mcam = &cam->mcam;
331 int i;
332
333 for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
334 if (!IS_ERR(mcam->clk[i]))
335 clk_disable_unprepare(mcam->clk[i]);
336 }
337
338 return 0;
339 }
340
mmpcam_suspend(struct device * dev)341 static int __maybe_unused mmpcam_suspend(struct device *dev)
342 {
343 struct mmp_camera *cam = dev_get_drvdata(dev);
344
345 if (!pm_runtime_suspended(dev))
346 mccic_suspend(&cam->mcam);
347 return 0;
348 }
349
mmpcam_resume(struct device * dev)350 static int __maybe_unused mmpcam_resume(struct device *dev)
351 {
352 struct mmp_camera *cam = dev_get_drvdata(dev);
353
354 if (!pm_runtime_suspended(dev))
355 return mccic_resume(&cam->mcam);
356 return 0;
357 }
358
359 static const struct dev_pm_ops mmpcam_pm_ops = {
360 SET_RUNTIME_PM_OPS(mmpcam_runtime_suspend, mmpcam_runtime_resume, NULL)
361 SET_SYSTEM_SLEEP_PM_OPS(mmpcam_suspend, mmpcam_resume)
362 };
363
364 static const struct of_device_id mmpcam_of_match[] = {
365 { .compatible = "marvell,mmp2-ccic", },
366 {},
367 };
368 MODULE_DEVICE_TABLE(of, mmpcam_of_match);
369
370 static struct platform_driver mmpcam_driver = {
371 .probe = mmpcam_probe,
372 .remove = mmpcam_platform_remove,
373 .driver = {
374 .name = "mmp-camera",
375 .of_match_table = of_match_ptr(mmpcam_of_match),
376 .pm = &mmpcam_pm_ops,
377 }
378 };
379
380 module_platform_driver(mmpcam_driver);
381