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.
5 * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
7 * This file may be distributed under the terms of the GNU General
8 * Public License, version 2.
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/v4l2-chip-ident.h>
22 #include <media/mmp-camera.h>
23 #include <linux/device.h>
24 #include <linux/platform_device.h>
25 #include <linux/gpio.h>
27 #include <linux/delay.h>
28 #include <linux/list.h>
31 #include "mcam-core.h"
33 MODULE_ALIAS("platform:mmp-camera");
34 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
35 MODULE_LICENSE("GPL");
39 struct platform_device *pdev;
40 struct mcam_camera mcam;
41 struct list_head devlist;
45 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
47 return container_of(mcam, struct mmp_camera, mcam);
51 * A silly little infrastructure so we can keep track of our devices.
52 * Chances are that we will never have more than one of them, but
53 * the Armada 610 *does* have two controllers...
56 static LIST_HEAD(mmpcam_devices);
57 static struct mutex mmpcam_devices_lock;
59 static void mmpcam_add_device(struct mmp_camera *cam)
61 mutex_lock(&mmpcam_devices_lock);
62 list_add(&cam->devlist, &mmpcam_devices);
63 mutex_unlock(&mmpcam_devices_lock);
66 static void mmpcam_remove_device(struct mmp_camera *cam)
68 mutex_lock(&mmpcam_devices_lock);
69 list_del(&cam->devlist);
70 mutex_unlock(&mmpcam_devices_lock);
74 * Platform dev remove passes us a platform_device, and there's
75 * no handy unused drvdata to stash a backpointer in. So just
76 * dig it out of our list.
78 static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
80 struct mmp_camera *cam;
82 mutex_lock(&mmpcam_devices_lock);
83 list_for_each_entry(cam, &mmpcam_devices, devlist) {
84 if (cam->pdev == pdev) {
85 mutex_unlock(&mmpcam_devices_lock);
89 mutex_unlock(&mmpcam_devices_lock);
97 * Power-related registers; this almost certainly belongs
100 * ARMADA 610 register manual, sec 7.2.1, p1842.
102 #define CPU_SUBSYS_PMU_BASE 0xd4282800
103 #define REG_CCIC_DCGCR 0x28 /* CCIC dyn clock gate ctrl reg */
104 #define REG_CCIC_CRCR 0x50 /* CCIC clk reset ctrl reg */
109 static void mmpcam_power_up_ctlr(struct mmp_camera *cam)
111 iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
112 iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
116 static void mmpcam_power_up(struct mcam_camera *mcam)
118 struct mmp_camera *cam = mcam_to_cam(mcam);
119 struct mmp_camera_platform_data *pdata;
121 * Turn on power and clocks to the controller.
123 mmpcam_power_up_ctlr(cam);
125 * Provide power to the sensor.
127 mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
128 pdata = cam->pdev->dev.platform_data;
129 gpio_set_value(pdata->sensor_power_gpio, 1);
131 mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
132 gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
134 gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
138 static void mmpcam_power_down(struct mcam_camera *mcam)
140 struct mmp_camera *cam = mcam_to_cam(mcam);
141 struct mmp_camera_platform_data *pdata;
143 * Turn off clocks and set reset lines
145 iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
146 iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
148 * Shut down the sensor.
150 pdata = cam->pdev->dev.platform_data;
151 gpio_set_value(pdata->sensor_power_gpio, 0);
152 gpio_set_value(pdata->sensor_reset_gpio, 0);
156 static irqreturn_t mmpcam_irq(int irq, void *data)
158 struct mcam_camera *mcam = data;
159 unsigned int irqs, handled;
161 spin_lock(&mcam->dev_lock);
162 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
163 handled = mccic_irq(mcam, irqs);
164 spin_unlock(&mcam->dev_lock);
165 return IRQ_RETVAL(handled);
169 static int mmpcam_probe(struct platform_device *pdev)
171 struct mmp_camera *cam;
172 struct mcam_camera *mcam;
173 struct resource *res;
174 struct mmp_camera_platform_data *pdata;
177 cam = kzalloc(sizeof(*cam), GFP_KERNEL);
181 INIT_LIST_HEAD(&cam->devlist);
184 mcam->plat_power_up = mmpcam_power_up;
185 mcam->plat_power_down = mmpcam_power_down;
186 mcam->dev = &pdev->dev;
188 mcam->chip_id = V4L2_IDENT_ARMADA610;
189 mcam->buffer_mode = B_DMA_sg;
190 spin_lock_init(&mcam->dev_lock);
192 * Get our I/O memory.
194 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
196 dev_err(&pdev->dev, "no iomem resource!\n");
200 mcam->regs = ioremap(res->start, resource_size(res));
201 if (mcam->regs == NULL) {
202 dev_err(&pdev->dev, "MMIO ioremap fail\n");
207 * Power/clock memory is elsewhere; get it too. Perhaps this
208 * should really be managed outside of this driver?
210 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
212 dev_err(&pdev->dev, "no power resource!\n");
216 cam->power_regs = ioremap(res->start, resource_size(res));
217 if (cam->power_regs == NULL) {
218 dev_err(&pdev->dev, "power MMIO ioremap fail\n");
223 * Find the i2c adapter. This assumes, of course, that the
224 * i2c bus is already up and functioning.
226 pdata = pdev->dev.platform_data;
227 mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
228 if (mcam->i2c_adapter == NULL) {
230 dev_err(&pdev->dev, "No i2c adapter\n");
236 ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
238 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
239 pdata->sensor_power_gpio);
242 gpio_direction_output(pdata->sensor_power_gpio, 0);
243 ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
245 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
246 pdata->sensor_reset_gpio);
249 gpio_direction_output(pdata->sensor_reset_gpio, 0);
251 * Power the device up and hand it off to the core.
253 mmpcam_power_up(mcam);
254 ret = mccic_register(mcam);
258 * Finally, set up our IRQ now that the core is ready to
261 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
266 cam->irq = res->start;
267 ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
270 mmpcam_add_device(cam);
275 mccic_shutdown(mcam);
277 mmpcam_power_down(mcam);
278 gpio_free(pdata->sensor_reset_gpio);
280 gpio_free(pdata->sensor_power_gpio);
282 iounmap(cam->power_regs);
291 static int mmpcam_remove(struct mmp_camera *cam)
293 struct mcam_camera *mcam = &cam->mcam;
294 struct mmp_camera_platform_data *pdata;
296 mmpcam_remove_device(cam);
297 free_irq(cam->irq, mcam);
298 mccic_shutdown(mcam);
299 mmpcam_power_down(mcam);
300 pdata = cam->pdev->dev.platform_data;
301 gpio_free(pdata->sensor_reset_gpio);
302 gpio_free(pdata->sensor_power_gpio);
303 iounmap(cam->power_regs);
309 static int mmpcam_platform_remove(struct platform_device *pdev)
311 struct mmp_camera *cam = mmpcam_find_device(pdev);
315 return mmpcam_remove(cam);
319 * Suspend/resume support.
323 static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state)
325 struct mmp_camera *cam = mmpcam_find_device(pdev);
327 if (state.event != PM_EVENT_SUSPEND)
329 mccic_suspend(&cam->mcam);
333 static int mmpcam_resume(struct platform_device *pdev)
335 struct mmp_camera *cam = mmpcam_find_device(pdev);
338 * Power up unconditionally just in case the core tries to
339 * touch a register even if nothing was active before; trust
340 * me, it's better this way.
342 mmpcam_power_up_ctlr(cam);
343 return mccic_resume(&cam->mcam);
349 static struct platform_driver mmpcam_driver = {
350 .probe = mmpcam_probe,
351 .remove = mmpcam_platform_remove,
353 .suspend = mmpcam_suspend,
354 .resume = mmpcam_resume,
357 .name = "mmp-camera",
363 static int __init mmpcam_init_module(void)
365 mutex_init(&mmpcam_devices_lock);
366 return platform_driver_register(&mmpcam_driver);
369 static void __exit mmpcam_exit_module(void)
371 platform_driver_unregister(&mmpcam_driver);
373 * platform_driver_unregister() should have emptied the list
375 if (!list_empty(&mmpcam_devices))
376 printk(KERN_ERR "mmp_camera leaving devices behind\n");
379 module_init(mmpcam_init_module);
380 module_exit(mmpcam_exit_module);