blob: 0d64e2d7474a52eebc06bf1dd84314ba7d32d288 [file] [log] [blame]
/*
* Support for the camera device found on Marvell MMP processors; known
* to work with the Armada 610 as used in the OLPC 1.75 system.
*
* Copyright 2011 Jonathan Corbet <corbet@lwn.net>
*
* This file may be distributed under the terms of the GNU General
* Public License, version 2.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/i2c-gpio.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <media/mmp-camera.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/pm.h>
#include "mcam-core.h"
MODULE_ALIAS("platform:mmp-camera");
MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
MODULE_LICENSE("GPL");
struct mmp_camera {
void *power_regs;
struct platform_device *pdev;
struct mcam_camera mcam;
struct list_head devlist;
int irq;
};
static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
{
return container_of(mcam, struct mmp_camera, mcam);
}
/*
* A silly little infrastructure so we can keep track of our devices.
* Chances are that we will never have more than one of them, but
* the Armada 610 *does* have two controllers...
*/
static LIST_HEAD(mmpcam_devices);
static struct mutex mmpcam_devices_lock;
static void mmpcam_add_device(struct mmp_camera *cam)
{
mutex_lock(&mmpcam_devices_lock);
list_add(&cam->devlist, &mmpcam_devices);
mutex_unlock(&mmpcam_devices_lock);
}
static void mmpcam_remove_device(struct mmp_camera *cam)
{
mutex_lock(&mmpcam_devices_lock);
list_del(&cam->devlist);
mutex_unlock(&mmpcam_devices_lock);
}
/*
* Platform dev remove passes us a platform_device, and there's
* no handy unused drvdata to stash a backpointer in. So just
* dig it out of our list.
*/
static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
{
struct mmp_camera *cam;
mutex_lock(&mmpcam_devices_lock);
list_for_each_entry(cam, &mmpcam_devices, devlist) {
if (cam->pdev == pdev) {
mutex_unlock(&mmpcam_devices_lock);
return cam;
}
}
mutex_unlock(&mmpcam_devices_lock);
return NULL;
}
/*
* Power-related registers; this almost certainly belongs
* somewhere else.
*
* ARMADA 610 register manual, sec 7.2.1, p1842.
*/
#define CPU_SUBSYS_PMU_BASE 0xd4282800
#define REG_CCIC_DCGCR 0x28 /* CCIC dyn clock gate ctrl reg */
#define REG_CCIC_CRCR 0x50 /* CCIC clk reset ctrl reg */
/*
* Power control.
*/
static void mmpcam_power_up(struct mcam_camera *mcam)
{
struct mmp_camera *cam = mcam_to_cam(mcam);
struct mmp_camera_platform_data *pdata;
/*
* Turn on power and clocks to the controller.
*/
iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
mdelay(1);
/*
* Provide power to the sensor.
*/
mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
pdata = cam->pdev->dev.platform_data;
gpio_set_value(pdata->sensor_power_gpio, 1);
mdelay(5);
mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
mdelay(5);
gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
mdelay(5);
}
static void mmpcam_power_down(struct mcam_camera *mcam)
{
struct mmp_camera *cam = mcam_to_cam(mcam);
struct mmp_camera_platform_data *pdata;
/*
* Turn off clocks and set reset lines
*/
iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
/*
* Shut down the sensor.
*/
pdata = cam->pdev->dev.platform_data;
gpio_set_value(pdata->sensor_power_gpio, 0);
gpio_set_value(pdata->sensor_reset_gpio, 0);
}
static irqreturn_t mmpcam_irq(int irq, void *data)
{
struct mcam_camera *mcam = data;
unsigned int irqs, handled;
spin_lock(&mcam->dev_lock);
irqs = mcam_reg_read(mcam, REG_IRQSTAT);
handled = mccic_irq(mcam, irqs);
spin_unlock(&mcam->dev_lock);
return IRQ_RETVAL(handled);
}
static int mmpcam_probe(struct platform_device *pdev)
{
struct mmp_camera *cam;
struct mcam_camera *mcam;
struct resource *res;
struct mmp_camera_platform_data *pdata;
int ret;
cam = kzalloc(sizeof(*cam), GFP_KERNEL);
if (cam == NULL)
return -ENOMEM;
cam->pdev = pdev;
INIT_LIST_HEAD(&cam->devlist);
mcam = &cam->mcam;
mcam->platform = MHP_Armada610;
mcam->plat_power_up = mmpcam_power_up;
mcam->plat_power_down = mmpcam_power_down;
mcam->dev = &pdev->dev;
mcam->use_smbus = 0;
mcam->chip_id = V4L2_IDENT_ARMADA610;
mcam->buffer_mode = B_DMA_sg;
spin_lock_init(&mcam->dev_lock);
/*
* Get our I/O memory.
*/
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no iomem resource!\n");
ret = -ENODEV;
goto out_free;
}
mcam->regs = ioremap(res->start, resource_size(res));
if (mcam->regs == NULL) {
dev_err(&pdev->dev, "MMIO ioremap fail\n");
ret = -ENODEV;
goto out_free;
}
/*
* Power/clock memory is elsewhere; get it too. Perhaps this
* should really be managed outside of this driver?
*/
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (res == NULL) {
dev_err(&pdev->dev, "no power resource!\n");
ret = -ENODEV;
goto out_unmap1;
}
cam->power_regs = ioremap(res->start, resource_size(res));
if (cam->power_regs == NULL) {
dev_err(&pdev->dev, "power MMIO ioremap fail\n");
ret = -ENODEV;
goto out_unmap1;
}
/*
* Find the i2c adapter. This assumes, of course, that the
* i2c bus is already up and functioning.
*/
pdata = pdev->dev.platform_data;
mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
if (mcam->i2c_adapter == NULL) {
ret = -ENODEV;
dev_err(&pdev->dev, "No i2c adapter\n");
goto out_unmap2;
}
/*
* Sensor GPIO pins.
*/
ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
if (ret) {
dev_err(&pdev->dev, "Can't get sensor power gpio %d",
pdata->sensor_power_gpio);
goto out_unmap2;
}
gpio_direction_output(pdata->sensor_power_gpio, 0);
ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
if (ret) {
dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
pdata->sensor_reset_gpio);
goto out_gpio;
}
gpio_direction_output(pdata->sensor_reset_gpio, 0);
/*
* Power the device up and hand it off to the core.
*/
mmpcam_power_up(mcam);
ret = mccic_register(mcam);
if (ret)
goto out_gpio2;
/*
* Finally, set up our IRQ now that the core is ready to
* deal with it.
*/
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (res == NULL) {
ret = -ENODEV;
goto out_unregister;
}
cam->irq = res->start;
ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
"mmp-camera", mcam);
if (ret == 0) {
mmpcam_add_device(cam);
return 0;
}
out_unregister:
mccic_shutdown(mcam);
out_gpio2:
mmpcam_power_down(mcam);
gpio_free(pdata->sensor_reset_gpio);
out_gpio:
gpio_free(pdata->sensor_power_gpio);
out_unmap2:
iounmap(cam->power_regs);
out_unmap1:
iounmap(mcam->regs);
out_free:
kfree(cam);
return ret;
}
static int mmpcam_remove(struct mmp_camera *cam)
{
struct mcam_camera *mcam = &cam->mcam;
struct mmp_camera_platform_data *pdata;
mmpcam_remove_device(cam);
free_irq(cam->irq, mcam);
mccic_shutdown(mcam);
mmpcam_power_down(mcam);
pdata = cam->pdev->dev.platform_data;
gpio_free(pdata->sensor_reset_gpio);
gpio_free(pdata->sensor_power_gpio);
iounmap(cam->power_regs);
iounmap(mcam->regs);
kfree(cam);
return 0;
}
static int mmpcam_platform_remove(struct platform_device *pdev)
{
struct mmp_camera *cam = mmpcam_find_device(pdev);
if (cam == NULL)
return -ENODEV;
return mmpcam_remove(cam);
}
/*
* Suspend/resume support.
*/
#ifdef CONFIG_PM
static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state)
{
struct mmp_camera *cam = mmpcam_find_device(pdev);
if (state.event != PM_EVENT_SUSPEND)
return 0;
mccic_suspend(&cam->mcam);
return 0;
}
static int mmpcam_resume(struct platform_device *pdev)
{
struct mmp_camera *cam = mmpcam_find_device(pdev);
/*
* Power up unconditionally just in case the core tries to
* touch a register even if nothing was active before; trust
* me, it's better this way.
*/
mmpcam_power_up(&cam->mcam);
return mccic_resume(&cam->mcam);
}
#endif
static struct platform_driver mmpcam_driver = {
.probe = mmpcam_probe,
.remove = mmpcam_platform_remove,
#ifdef CONFIG_PM
.suspend = mmpcam_suspend,
.resume = mmpcam_resume,
#endif
.driver = {
.name = "mmp-camera",
.owner = THIS_MODULE
}
};
static int __init mmpcam_init_module(void)
{
mutex_init(&mmpcam_devices_lock);
return platform_driver_register(&mmpcam_driver);
}
static void __exit mmpcam_exit_module(void)
{
platform_driver_unregister(&mmpcam_driver);
/*
* platform_driver_unregister() should have emptied the list
*/
if (!list_empty(&mmpcam_devices))
printk(KERN_ERR "mmp_camera leaving devices behind\n");
}
module_init(mmpcam_init_module);
module_exit(mmpcam_exit_module);