1 /*
2 * Support for the camera device found on Marvell MMP processors; known
3 * to work with the Armada 610 as used in the OLPC 1.75 system.
4 *
5 * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
6 *
7 * This file may be distributed under the terms of the GNU General
8 * Public License, version 2.
9 */
10
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/i2c.h>
15 #include <linux/i2c-gpio.h>
16 #include <linux/interrupt.h>
17 #include <linux/spinlock.h>
18 #include <linux/slab.h>
19 #include <linux/videodev2.h>
20 #include <media/v4l2-device.h>
21 #include <media/mmp-camera.h>
22 #include <linux/device.h>
23 #include <linux/platform_device.h>
24 #include <linux/gpio.h>
25 #include <linux/io.h>
26 #include <linux/delay.h>
27 #include <linux/list.h>
28 #include <linux/pm.h>
29 #include <linux/clk.h>
30
31 #include "mcam-core.h"
32
33 MODULE_ALIAS("platform:mmp-camera");
34 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
35 MODULE_LICENSE("GPL");
36
37 static char *mcam_clks[] = {"CCICAXICLK", "CCICFUNCLK", "CCICPHYCLK"};
38
39 struct mmp_camera {
40 void *power_regs;
41 struct platform_device *pdev;
42 struct mcam_camera mcam;
43 struct list_head devlist;
44 struct clk *mipi_clk;
45 int irq;
46 };
47
mcam_to_cam(struct mcam_camera * mcam)48 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
49 {
50 return container_of(mcam, struct mmp_camera, mcam);
51 }
52
53 /*
54 * A silly little infrastructure so we can keep track of our devices.
55 * Chances are that we will never have more than one of them, but
56 * the Armada 610 *does* have two controllers...
57 */
58
59 static LIST_HEAD(mmpcam_devices);
60 static struct mutex mmpcam_devices_lock;
61
mmpcam_add_device(struct mmp_camera * cam)62 static void mmpcam_add_device(struct mmp_camera *cam)
63 {
64 mutex_lock(&mmpcam_devices_lock);
65 list_add(&cam->devlist, &mmpcam_devices);
66 mutex_unlock(&mmpcam_devices_lock);
67 }
68
mmpcam_remove_device(struct mmp_camera * cam)69 static void mmpcam_remove_device(struct mmp_camera *cam)
70 {
71 mutex_lock(&mmpcam_devices_lock);
72 list_del(&cam->devlist);
73 mutex_unlock(&mmpcam_devices_lock);
74 }
75
76 /*
77 * Platform dev remove passes us a platform_device, and there's
78 * no handy unused drvdata to stash a backpointer in. So just
79 * dig it out of our list.
80 */
mmpcam_find_device(struct platform_device * pdev)81 static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
82 {
83 struct mmp_camera *cam;
84
85 mutex_lock(&mmpcam_devices_lock);
86 list_for_each_entry(cam, &mmpcam_devices, devlist) {
87 if (cam->pdev == pdev) {
88 mutex_unlock(&mmpcam_devices_lock);
89 return cam;
90 }
91 }
92 mutex_unlock(&mmpcam_devices_lock);
93 return NULL;
94 }
95
96
97
98
99 /*
100 * Power-related registers; this almost certainly belongs
101 * somewhere else.
102 *
103 * ARMADA 610 register manual, sec 7.2.1, p1842.
104 */
105 #define CPU_SUBSYS_PMU_BASE 0xd4282800
106 #define REG_CCIC_DCGCR 0x28 /* CCIC dyn clock gate ctrl reg */
107 #define REG_CCIC_CRCR 0x50 /* CCIC clk reset ctrl reg */
108 #define REG_CCIC2_CRCR 0xf4 /* CCIC2 clk reset ctrl reg */
109
mcam_clk_enable(struct mcam_camera * mcam)110 static void mcam_clk_enable(struct mcam_camera *mcam)
111 {
112 unsigned int i;
113
114 for (i = 0; i < NR_MCAM_CLK; i++) {
115 if (!IS_ERR(mcam->clk[i]))
116 clk_prepare_enable(mcam->clk[i]);
117 }
118 }
119
mcam_clk_disable(struct mcam_camera * mcam)120 static void mcam_clk_disable(struct mcam_camera *mcam)
121 {
122 int i;
123
124 for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
125 if (!IS_ERR(mcam->clk[i]))
126 clk_disable_unprepare(mcam->clk[i]);
127 }
128 }
129
130 /*
131 * Power control.
132 */
mmpcam_power_up_ctlr(struct mmp_camera * cam)133 static void mmpcam_power_up_ctlr(struct mmp_camera *cam)
134 {
135 iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
136 iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
137 mdelay(1);
138 }
139
mmpcam_power_up(struct mcam_camera * mcam)140 static int mmpcam_power_up(struct mcam_camera *mcam)
141 {
142 struct mmp_camera *cam = mcam_to_cam(mcam);
143 struct mmp_camera_platform_data *pdata;
144
145 /*
146 * Turn on power and clocks to the controller.
147 */
148 mmpcam_power_up_ctlr(cam);
149 /*
150 * Provide power to the sensor.
151 */
152 mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
153 pdata = cam->pdev->dev.platform_data;
154 gpio_set_value(pdata->sensor_power_gpio, 1);
155 mdelay(5);
156 mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
157 gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
158 mdelay(5);
159 gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
160 mdelay(5);
161
162 mcam_clk_enable(mcam);
163
164 return 0;
165 }
166
mmpcam_power_down(struct mcam_camera * mcam)167 static void mmpcam_power_down(struct mcam_camera *mcam)
168 {
169 struct mmp_camera *cam = mcam_to_cam(mcam);
170 struct mmp_camera_platform_data *pdata;
171 /*
172 * Turn off clocks and set reset lines
173 */
174 iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
175 iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
176 /*
177 * Shut down the sensor.
178 */
179 pdata = cam->pdev->dev.platform_data;
180 gpio_set_value(pdata->sensor_power_gpio, 0);
181 gpio_set_value(pdata->sensor_reset_gpio, 0);
182
183 mcam_clk_disable(mcam);
184 }
185
mcam_ctlr_reset(struct mcam_camera * mcam)186 void mcam_ctlr_reset(struct mcam_camera *mcam)
187 {
188 unsigned long val;
189 struct mmp_camera *cam = mcam_to_cam(mcam);
190
191 if (mcam->ccic_id) {
192 /*
193 * Using CCIC2
194 */
195 val = ioread32(cam->power_regs + REG_CCIC2_CRCR);
196 iowrite32(val & ~0x2, cam->power_regs + REG_CCIC2_CRCR);
197 iowrite32(val | 0x2, cam->power_regs + REG_CCIC2_CRCR);
198 } else {
199 /*
200 * Using CCIC1
201 */
202 val = ioread32(cam->power_regs + REG_CCIC_CRCR);
203 iowrite32(val & ~0x2, cam->power_regs + REG_CCIC_CRCR);
204 iowrite32(val | 0x2, cam->power_regs + REG_CCIC_CRCR);
205 }
206 }
207
208 /*
209 * calc the dphy register values
210 * There are three dphy registers being used.
211 * dphy[0] - CSI2_DPHY3
212 * dphy[1] - CSI2_DPHY5
213 * dphy[2] - CSI2_DPHY6
214 * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
215 * or be calculated dynamically
216 */
mmpcam_calc_dphy(struct mcam_camera * mcam)217 void mmpcam_calc_dphy(struct mcam_camera *mcam)
218 {
219 struct mmp_camera *cam = mcam_to_cam(mcam);
220 struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
221 struct device *dev = &cam->pdev->dev;
222 unsigned long tx_clk_esc;
223
224 /*
225 * If CSI2_DPHY3 is calculated dynamically,
226 * pdata->lane_clk should be already set
227 * either in the board driver statically
228 * or in the sensor driver dynamically.
229 */
230 /*
231 * dphy[0] - CSI2_DPHY3:
232 * bit 0 ~ bit 7: HS Term Enable.
233 * defines the time that the DPHY
234 * wait before enabling the data
235 * lane termination after detecting
236 * that the sensor has driven the data
237 * lanes to the LP00 bridge state.
238 * The value is calculated by:
239 * (Max T(D_TERM_EN)/Period(DDR)) - 1
240 * bit 8 ~ bit 15: HS_SETTLE
241 * Time interval during which the HS
242 * receiver shall ignore any Data Lane
243 * HS transistions.
244 * The vaule has been calibrated on
245 * different boards. It seems to work well.
246 *
247 * More detail please refer
248 * MIPI Alliance Spectification for D-PHY
249 * document for explanation of HS-SETTLE
250 * and D-TERM-EN.
251 */
252 switch (pdata->dphy3_algo) {
253 case DPHY3_ALGO_PXA910:
254 /*
255 * Calculate CSI2_DPHY3 algo for PXA910
256 */
257 pdata->dphy[0] =
258 (((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
259 | (1 + pdata->lane_clk * 35 / 1000);
260 break;
261 case DPHY3_ALGO_PXA2128:
262 /*
263 * Calculate CSI2_DPHY3 algo for PXA2128
264 */
265 pdata->dphy[0] =
266 (((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
267 | (1 + pdata->lane_clk * 35 / 1000);
268 break;
269 default:
270 /*
271 * Use default CSI2_DPHY3 value for PXA688/PXA988
272 */
273 dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
274 }
275
276 /*
277 * mipi_clk will never be changed, it is a fixed value on MMP
278 */
279 if (IS_ERR(cam->mipi_clk))
280 return;
281
282 /* get the escape clk, this is hard coded */
283 clk_prepare_enable(cam->mipi_clk);
284 tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
285 clk_disable_unprepare(cam->mipi_clk);
286 /*
287 * dphy[2] - CSI2_DPHY6:
288 * bit 0 ~ bit 7: CK Term Enable
289 * Time for the Clock Lane receiver to enable the HS line
290 * termination. The value is calculated similarly with
291 * HS Term Enable
292 * bit 8 ~ bit 15: CK Settle
293 * Time interval during which the HS receiver shall ignore
294 * any Clock Lane HS transitions.
295 * The value is calibrated on the boards.
296 */
297 pdata->dphy[2] =
298 ((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
299 | (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
300
301 dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
302 pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
303 }
304
mmpcam_irq(int irq,void * data)305 static irqreturn_t mmpcam_irq(int irq, void *data)
306 {
307 struct mcam_camera *mcam = data;
308 unsigned int irqs, handled;
309
310 spin_lock(&mcam->dev_lock);
311 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
312 handled = mccic_irq(mcam, irqs);
313 spin_unlock(&mcam->dev_lock);
314 return IRQ_RETVAL(handled);
315 }
316
mcam_init_clk(struct mcam_camera * mcam)317 static void mcam_init_clk(struct mcam_camera *mcam)
318 {
319 unsigned int i;
320
321 for (i = 0; i < NR_MCAM_CLK; i++) {
322 if (mcam_clks[i] != NULL) {
323 /* Some clks are not necessary on some boards
324 * We still try to run even it fails getting clk
325 */
326 mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
327 if (IS_ERR(mcam->clk[i]))
328 dev_warn(mcam->dev, "Could not get clk: %s\n",
329 mcam_clks[i]);
330 }
331 }
332 }
333
mmpcam_probe(struct platform_device * pdev)334 static int mmpcam_probe(struct platform_device *pdev)
335 {
336 struct mmp_camera *cam;
337 struct mcam_camera *mcam;
338 struct resource *res;
339 struct mmp_camera_platform_data *pdata;
340 int ret;
341
342 pdata = pdev->dev.platform_data;
343 if (!pdata)
344 return -ENODEV;
345
346 cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
347 if (cam == NULL)
348 return -ENOMEM;
349 cam->pdev = pdev;
350 INIT_LIST_HEAD(&cam->devlist);
351
352 mcam = &cam->mcam;
353 mcam->plat_power_up = mmpcam_power_up;
354 mcam->plat_power_down = mmpcam_power_down;
355 mcam->ctlr_reset = mcam_ctlr_reset;
356 mcam->calc_dphy = mmpcam_calc_dphy;
357 mcam->dev = &pdev->dev;
358 mcam->use_smbus = 0;
359 mcam->ccic_id = pdev->id;
360 mcam->mclk_min = pdata->mclk_min;
361 mcam->mclk_src = pdata->mclk_src;
362 mcam->mclk_div = pdata->mclk_div;
363 mcam->bus_type = pdata->bus_type;
364 mcam->dphy = pdata->dphy;
365 if (mcam->bus_type == V4L2_MBUS_CSI2) {
366 cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
367 if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
368 return PTR_ERR(cam->mipi_clk);
369 }
370 mcam->mipi_enabled = false;
371 mcam->lane = pdata->lane;
372 mcam->chip_id = MCAM_ARMADA610;
373 mcam->buffer_mode = B_DMA_sg;
374 strlcpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
375 spin_lock_init(&mcam->dev_lock);
376 /*
377 * Get our I/O memory.
378 */
379 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
380 mcam->regs = devm_ioremap_resource(&pdev->dev, res);
381 if (IS_ERR(mcam->regs))
382 return PTR_ERR(mcam->regs);
383 mcam->regs_size = resource_size(res);
384 /*
385 * Power/clock memory is elsewhere; get it too. Perhaps this
386 * should really be managed outside of this driver?
387 */
388 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
389 cam->power_regs = devm_ioremap_resource(&pdev->dev, res);
390 if (IS_ERR(cam->power_regs))
391 return PTR_ERR(cam->power_regs);
392 /*
393 * Find the i2c adapter. This assumes, of course, that the
394 * i2c bus is already up and functioning.
395 */
396 mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
397 if (mcam->i2c_adapter == NULL) {
398 dev_err(&pdev->dev, "No i2c adapter\n");
399 return -ENODEV;
400 }
401 /*
402 * Sensor GPIO pins.
403 */
404 ret = devm_gpio_request(&pdev->dev, pdata->sensor_power_gpio,
405 "cam-power");
406 if (ret) {
407 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
408 pdata->sensor_power_gpio);
409 return ret;
410 }
411 gpio_direction_output(pdata->sensor_power_gpio, 0);
412 ret = devm_gpio_request(&pdev->dev, pdata->sensor_reset_gpio,
413 "cam-reset");
414 if (ret) {
415 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
416 pdata->sensor_reset_gpio);
417 return ret;
418 }
419 gpio_direction_output(pdata->sensor_reset_gpio, 0);
420
421 mcam_init_clk(mcam);
422
423 /*
424 * Power the device up and hand it off to the core.
425 */
426 ret = mmpcam_power_up(mcam);
427 if (ret)
428 return ret;
429 ret = mccic_register(mcam);
430 if (ret)
431 goto out_power_down;
432 /*
433 * Finally, set up our IRQ now that the core is ready to
434 * deal with it.
435 */
436 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
437 if (res == NULL) {
438 ret = -ENODEV;
439 goto out_unregister;
440 }
441 cam->irq = res->start;
442 ret = devm_request_irq(&pdev->dev, cam->irq, mmpcam_irq, IRQF_SHARED,
443 "mmp-camera", mcam);
444 if (ret == 0) {
445 mmpcam_add_device(cam);
446 return 0;
447 }
448
449 out_unregister:
450 mccic_shutdown(mcam);
451 out_power_down:
452 mmpcam_power_down(mcam);
453 return ret;
454 }
455
456
mmpcam_remove(struct mmp_camera * cam)457 static int mmpcam_remove(struct mmp_camera *cam)
458 {
459 struct mcam_camera *mcam = &cam->mcam;
460
461 mmpcam_remove_device(cam);
462 mccic_shutdown(mcam);
463 mmpcam_power_down(mcam);
464 return 0;
465 }
466
mmpcam_platform_remove(struct platform_device * pdev)467 static int mmpcam_platform_remove(struct platform_device *pdev)
468 {
469 struct mmp_camera *cam = mmpcam_find_device(pdev);
470
471 if (cam == NULL)
472 return -ENODEV;
473 return mmpcam_remove(cam);
474 }
475
476 /*
477 * Suspend/resume support.
478 */
479 #ifdef CONFIG_PM
480
mmpcam_suspend(struct platform_device * pdev,pm_message_t state)481 static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state)
482 {
483 struct mmp_camera *cam = mmpcam_find_device(pdev);
484
485 if (state.event != PM_EVENT_SUSPEND)
486 return 0;
487 mccic_suspend(&cam->mcam);
488 return 0;
489 }
490
mmpcam_resume(struct platform_device * pdev)491 static int mmpcam_resume(struct platform_device *pdev)
492 {
493 struct mmp_camera *cam = mmpcam_find_device(pdev);
494
495 /*
496 * Power up unconditionally just in case the core tries to
497 * touch a register even if nothing was active before; trust
498 * me, it's better this way.
499 */
500 mmpcam_power_up_ctlr(cam);
501 return mccic_resume(&cam->mcam);
502 }
503
504 #endif
505
506
507 static struct platform_driver mmpcam_driver = {
508 .probe = mmpcam_probe,
509 .remove = mmpcam_platform_remove,
510 #ifdef CONFIG_PM
511 .suspend = mmpcam_suspend,
512 .resume = mmpcam_resume,
513 #endif
514 .driver = {
515 .name = "mmp-camera",
516 }
517 };
518
519
mmpcam_init_module(void)520 static int __init mmpcam_init_module(void)
521 {
522 mutex_init(&mmpcam_devices_lock);
523 return platform_driver_register(&mmpcam_driver);
524 }
525
mmpcam_exit_module(void)526 static void __exit mmpcam_exit_module(void)
527 {
528 platform_driver_unregister(&mmpcam_driver);
529 /*
530 * platform_driver_unregister() should have emptied the list
531 */
532 if (!list_empty(&mmpcam_devices))
533 printk(KERN_ERR "mmp_camera leaving devices behind\n");
534 }
535
536 module_init(mmpcam_init_module);
537 module_exit(mmpcam_exit_module);
538