android_kernel_motorola_sm6225/drivers/media/video/marvell-ccic/mmp-driver.c
Jonathan Corbet 4a0abfaa96 [media] mmp-camera: Don't power up the sensor on resume
We still need to power up the controller to avoid unsightly self-immolation
should something try to access its registers, but the sensor can stay
powered down unless the camera was actually operating at suspend time.
This gets rid of the camera LED flash on resume, fixing OLPC bug #11644.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-03-19 22:16:46 -03:00

381 lines
8.9 KiB
C

/*
* 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_ctlr(struct mmp_camera *cam)
{
iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
mdelay(1);
}
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.
*/
mmpcam_power_up_ctlr(cam);
/*
* 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_ctlr(cam);
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);