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>
30 #include "mcam-core.h"
32 MODULE_ALIAS("platform:mmp-camera");
33 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
34 MODULE_LICENSE("GPL");
38 struct platform_device *pdev;
39 struct mcam_camera mcam;
40 struct list_head devlist;
44 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
46 return container_of(mcam, struct mmp_camera, mcam);
50 * A silly little infrastructure so we can keep track of our devices.
51 * Chances are that we will never have more than one of them, but
52 * the Armada 610 *does* have two controllers...
55 static LIST_HEAD(mmpcam_devices);
56 static struct mutex mmpcam_devices_lock;
58 static void mmpcam_add_device(struct mmp_camera *cam)
60 mutex_lock(&mmpcam_devices_lock);
61 list_add(&cam->devlist, &mmpcam_devices);
62 mutex_unlock(&mmpcam_devices_lock);
65 static void mmpcam_remove_device(struct mmp_camera *cam)
67 mutex_lock(&mmpcam_devices_lock);
68 list_del(&cam->devlist);
69 mutex_unlock(&mmpcam_devices_lock);
73 * Platform dev remove passes us a platform_device, and there's
74 * no handy unused drvdata to stash a backpointer in. So just
75 * dig it out of our list.
77 static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
79 struct mmp_camera *cam;
81 mutex_lock(&mmpcam_devices_lock);
82 list_for_each_entry(cam, &mmpcam_devices, devlist) {
83 if (cam->pdev == pdev) {
84 mutex_unlock(&mmpcam_devices_lock);
88 mutex_unlock(&mmpcam_devices_lock);
96 * Power-related registers; this almost certainly belongs
99 * ARMADA 610 register manual, sec 7.2.1, p1842.
101 #define CPU_SUBSYS_PMU_BASE 0xd4282800
102 #define REG_CCIC_DCGCR 0x28 /* CCIC dyn clock gate ctrl reg */
103 #define REG_CCIC_CRCR 0x50 /* CCIC clk reset ctrl reg */
108 static void mmpcam_power_up(struct mcam_camera *mcam)
110 struct mmp_camera *cam = mcam_to_cam(mcam);
111 struct mmp_camera_platform_data *pdata;
113 * Turn on power and clocks to the controller.
115 iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
116 iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
119 * Provide power to the sensor.
121 mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
122 pdata = cam->pdev->dev.platform_data;
123 gpio_set_value(pdata->sensor_power_gpio, 1);
125 mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
126 gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
128 gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
132 static void mmpcam_power_down(struct mcam_camera *mcam)
134 struct mmp_camera *cam = mcam_to_cam(mcam);
135 struct mmp_camera_platform_data *pdata;
137 * Turn off clocks and set reset lines
139 iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
140 iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
142 * Shut down the sensor.
144 pdata = cam->pdev->dev.platform_data;
145 gpio_set_value(pdata->sensor_power_gpio, 0);
146 gpio_set_value(pdata->sensor_reset_gpio, 0);
150 static irqreturn_t mmpcam_irq(int irq, void *data)
152 struct mcam_camera *mcam = data;
153 unsigned int irqs, handled;
155 spin_lock(&mcam->dev_lock);
156 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
157 handled = mccic_irq(mcam, irqs);
158 spin_unlock(&mcam->dev_lock);
159 return IRQ_RETVAL(handled);
163 static int mmpcam_probe(struct platform_device *pdev)
165 struct mmp_camera *cam;
166 struct mcam_camera *mcam;
167 struct resource *res;
168 struct mmp_camera_platform_data *pdata;
171 cam = kzalloc(sizeof(*cam), GFP_KERNEL);
175 INIT_LIST_HEAD(&cam->devlist);
178 mcam->platform = MHP_Armada610;
179 mcam->plat_power_up = mmpcam_power_up;
180 mcam->plat_power_down = mmpcam_power_down;
181 mcam->dev = &pdev->dev;
183 mcam->chip_id = V4L2_IDENT_ARMADA610;
184 mcam->buffer_mode = B_DMA_sg;
185 spin_lock_init(&mcam->dev_lock);
187 * Get our I/O memory.
189 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
191 dev_err(&pdev->dev, "no iomem resource!\n");
195 mcam->regs = ioremap(res->start, resource_size(res));
196 if (mcam->regs == NULL) {
197 dev_err(&pdev->dev, "MMIO ioremap fail\n");
202 * Power/clock memory is elsewhere; get it too. Perhaps this
203 * should really be managed outside of this driver?
205 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
207 dev_err(&pdev->dev, "no power resource!\n");
211 cam->power_regs = ioremap(res->start, resource_size(res));
212 if (cam->power_regs == NULL) {
213 dev_err(&pdev->dev, "power MMIO ioremap fail\n");
218 * Find the i2c adapter. This assumes, of course, that the
219 * i2c bus is already up and functioning.
221 pdata = pdev->dev.platform_data;
222 mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
223 if (mcam->i2c_adapter == NULL) {
225 dev_err(&pdev->dev, "No i2c adapter\n");
231 ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
233 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
234 pdata->sensor_power_gpio);
237 gpio_direction_output(pdata->sensor_power_gpio, 0);
238 ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
240 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
241 pdata->sensor_reset_gpio);
244 gpio_direction_output(pdata->sensor_reset_gpio, 0);
246 * Power the device up and hand it off to the core.
248 mmpcam_power_up(mcam);
249 ret = mccic_register(mcam);
253 * Finally, set up our IRQ now that the core is ready to
256 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
261 cam->irq = res->start;
262 ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
265 mmpcam_add_device(cam);
270 mccic_shutdown(mcam);
272 mmpcam_power_down(mcam);
273 gpio_free(pdata->sensor_reset_gpio);
275 gpio_free(pdata->sensor_power_gpio);
277 iounmap(cam->power_regs);
286 static int mmpcam_remove(struct mmp_camera *cam)
288 struct mcam_camera *mcam = &cam->mcam;
289 struct mmp_camera_platform_data *pdata;
291 mmpcam_remove_device(cam);
292 free_irq(cam->irq, mcam);
293 mccic_shutdown(mcam);
294 mmpcam_power_down(mcam);
295 pdata = cam->pdev->dev.platform_data;
296 gpio_free(pdata->sensor_reset_gpio);
297 gpio_free(pdata->sensor_power_gpio);
298 iounmap(cam->power_regs);
304 static int mmpcam_platform_remove(struct platform_device *pdev)
306 struct mmp_camera *cam = mmpcam_find_device(pdev);
310 return mmpcam_remove(cam);
314 static struct platform_driver mmpcam_driver = {
315 .probe = mmpcam_probe,
316 .remove = mmpcam_platform_remove,
318 .name = "mmp-camera",
324 static int __init mmpcam_init_module(void)
326 mutex_init(&mmpcam_devices_lock);
327 return platform_driver_register(&mmpcam_driver);
330 static void __exit mmpcam_exit_module(void)
332 platform_driver_unregister(&mmpcam_driver);
334 * platform_driver_unregister() should have emptied the list
336 if (!list_empty(&mmpcam_devices))
337 printk(KERN_ERR "mmp_camera leaving devices behind\n");
340 module_init(mmpcam_init_module);
341 module_exit(mmpcam_exit_module);