drivers/media/platform/marvell-ccic/mmp-driver.c - kernel/msm-4.9 - Gitiles

 /*
  * 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/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 <linux/clk.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;
 	struct clk *mipi_clk;
 	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 int mmpcam_power_up(struct mcam_camera *mcam)
 {
 	struct mmp_camera *cam = mcam_to_cam(mcam);
 	struct mmp_camera_platform_data *pdata;

 	if (mcam->bus_type == V4L2_MBUS_CSI2) {
 		cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
 		if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
 			return PTR_ERR(cam->mipi_clk);
 	}

 /*
  * 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);
 	return 0;
 }

 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);

 	if (mcam->bus_type == V4L2_MBUS_CSI2 && !IS_ERR(cam->mipi_clk)) {
 		if (cam->mipi_clk)
 			devm_clk_put(mcam->dev, cam->mipi_clk);
 		cam->mipi_clk = NULL;
 	}
 }

 /*
  * calc the dphy register values
  * There are three dphy registers being used.
  * dphy[0] - CSI2_DPHY3
  * dphy[1] - CSI2_DPHY5
  * dphy[2] - CSI2_DPHY6
  * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
  * or be calculated dynamically
  */
 void mmpcam_calc_dphy(struct mcam_camera *mcam)
 {
 	struct mmp_camera *cam = mcam_to_cam(mcam);
 	struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
 	struct device *dev = &cam->pdev->dev;
 	unsigned long tx_clk_esc;

 	/*
 	 * If CSI2_DPHY3 is calculated dynamically,
 	 * pdata->lane_clk should be already set
 	 * either in the board driver statically
 	 * or in the sensor driver dynamically.
 	 */
 	/*
 	 * dphy[0] - CSI2_DPHY3:
 	 *  bit 0 ~ bit 7: HS Term Enable.
 	 *   defines the time that the DPHY
 	 *   wait before enabling the data
 	 *   lane termination after detecting
 	 *   that the sensor has driven the data
 	 *   lanes to the LP00 bridge state.
 	 *   The value is calculated by:
 	 *   (Max T(D_TERM_EN)/Period(DDR)) - 1
 	 *  bit 8 ~ bit 15: HS_SETTLE
 	 *   Time interval during which the HS
 	 *   receiver shall ignore any Data Lane
 	 *   HS transistions.
 	 *   The vaule has been calibrated on
 	 *   different boards. It seems to work well.
 	 *
 	 *  More detail please refer
 	 *  MIPI Alliance Spectification for D-PHY
 	 *  document for explanation of HS-SETTLE
 	 *  and D-TERM-EN.
 	 */
 	switch (pdata->dphy3_algo) {
 	case DPHY3_ALGO_PXA910:
 		/*
 		 * Calculate CSI2_DPHY3 algo for PXA910
 		 */
 		pdata->dphy[0] =
 			(((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
 			| (1 + pdata->lane_clk * 35 / 1000);
 		break;
 	case DPHY3_ALGO_PXA2128:
 		/*
 		 * Calculate CSI2_DPHY3 algo for PXA2128
 		 */
 		pdata->dphy[0] =
 			(((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
 			| (1 + pdata->lane_clk * 35 / 1000);
 		break;
 	default:
 		/*
 		 * Use default CSI2_DPHY3 value for PXA688/PXA988
 		 */
 		dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
 	}

 	/*
 	 * mipi_clk will never be changed, it is a fixed value on MMP
 	 */
 	if (IS_ERR(cam->mipi_clk))
 		return;

 	/* get the escape clk, this is hard coded */
 	tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;

 	/*
 	 * dphy[2] - CSI2_DPHY6:
 	 * bit 0 ~ bit 7: CK Term Enable
 	 *  Time for the Clock Lane receiver to enable the HS line
 	 *  termination. The value is calculated similarly with
 	 *  HS Term Enable
 	 * bit 8 ~ bit 15: CK Settle
 	 *  Time interval during which the HS receiver shall ignore
 	 *  any Clock Lane HS transitions.
 	 *  The value is calibrated on the boards.
 	 */
 	pdata->dphy[2] =
 		((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
 		| (((38 * tx_clk_esc) / 1000 - 1) & 0xff);

 	dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
 		pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
 }

 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;

 	pdata = pdev->dev.platform_data;
 	if (!pdata)
 		return -ENODEV;

 	cam = kzalloc(sizeof(*cam), GFP_KERNEL);
 	if (cam == NULL)
 		return -ENOMEM;
 	cam->pdev = pdev;
 	cam->mipi_clk = NULL;
 	INIT_LIST_HEAD(&cam->devlist);

 	mcam = &cam->mcam;
 	mcam->plat_power_up = mmpcam_power_up;
 	mcam->plat_power_down = mmpcam_power_down;
 	mcam->calc_dphy = mmpcam_calc_dphy;
 	mcam->dev = &pdev->dev;
 	mcam->use_smbus = 0;
 	mcam->mclk_min = pdata->mclk_min;
 	mcam->mclk_src = pdata->mclk_src;
 	mcam->mclk_div = pdata->mclk_div;
 	mcam->bus_type = pdata->bus_type;
 	mcam->dphy = pdata->dphy;
 	mcam->mipi_enabled = false;
 	mcam->lane = pdata->lane;
 	mcam->chip_id = MCAM_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;
 	}
 	mcam->regs_size = resource_size(res);
 	/*
 	 * 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.
 	 */
 	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.
 	 */
 	ret = mmpcam_power_up(mcam);
 	if (ret)
 		goto out_gpio2;
 	ret = mccic_register(mcam);
 	if (ret)
 		goto out_pwdn;
 	/*
 	 * 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_pwdn:
 	mmpcam_power_down(mcam);
 out_gpio2:
 	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);
	/*
	* 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/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 <linux/clk.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;
	struct clk *mipi_clk;
	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 int mmpcam_power_up(struct mcam_camera *mcam)
	{
	struct mmp_camera *cam = mcam_to_cam(mcam);
	struct mmp_camera_platform_data *pdata;

	if (mcam->bus_type == V4L2_MBUS_CSI2) {
	cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
	if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
	return PTR_ERR(cam->mipi_clk);
	}

	/*
	* 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);
	return 0;
	}

	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);

	if (mcam->bus_type == V4L2_MBUS_CSI2 && !IS_ERR(cam->mipi_clk)) {
	if (cam->mipi_clk)
	devm_clk_put(mcam->dev, cam->mipi_clk);
	cam->mipi_clk = NULL;
	}
	}

	/*
	* calc the dphy register values
	* There are three dphy registers being used.
	* dphy[0] - CSI2_DPHY3
	* dphy[1] - CSI2_DPHY5
	* dphy[2] - CSI2_DPHY6
	* CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
	* or be calculated dynamically
	*/
	void mmpcam_calc_dphy(struct mcam_camera *mcam)
	{
	struct mmp_camera *cam = mcam_to_cam(mcam);
	struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
	struct device *dev = &cam->pdev->dev;
	unsigned long tx_clk_esc;

	/*
	* If CSI2_DPHY3 is calculated dynamically,
	* pdata->lane_clk should be already set
	* either in the board driver statically
	* or in the sensor driver dynamically.
	*/
	/*
	* dphy[0] - CSI2_DPHY3:
	* bit 0 ~ bit 7: HS Term Enable.
	* defines the time that the DPHY
	* wait before enabling the data
	* lane termination after detecting
	* that the sensor has driven the data
	* lanes to the LP00 bridge state.
	* The value is calculated by:
	* (Max T(D_TERM_EN)/Period(DDR)) - 1
	* bit 8 ~ bit 15: HS_SETTLE
	* Time interval during which the HS
	* receiver shall ignore any Data Lane
	* HS transistions.
	* The vaule has been calibrated on
	* different boards. It seems to work well.
	*
	* More detail please refer
	* MIPI Alliance Spectification for D-PHY
	* document for explanation of HS-SETTLE
	* and D-TERM-EN.
	*/
	switch (pdata->dphy3_algo) {
	case DPHY3_ALGO_PXA910:
	/*
	* Calculate CSI2_DPHY3 algo for PXA910
	*/
	pdata->dphy[0] =
	(((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
	\| (1 + pdata->lane_clk * 35 / 1000);
	break;
	case DPHY3_ALGO_PXA2128:
	/*
	* Calculate CSI2_DPHY3 algo for PXA2128
	*/
	pdata->dphy[0] =
	(((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
	\| (1 + pdata->lane_clk * 35 / 1000);
	break;
	default:
	/*
	* Use default CSI2_DPHY3 value for PXA688/PXA988
	*/
	dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
	}

	/*
	* mipi_clk will never be changed, it is a fixed value on MMP
	*/
	if (IS_ERR(cam->mipi_clk))
	return;

	/* get the escape clk, this is hard coded */
	tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;

	/*
	* dphy[2] - CSI2_DPHY6:
	* bit 0 ~ bit 7: CK Term Enable
	* Time for the Clock Lane receiver to enable the HS line
	* termination. The value is calculated similarly with
	* HS Term Enable
	* bit 8 ~ bit 15: CK Settle
	* Time interval during which the HS receiver shall ignore
	* any Clock Lane HS transitions.
	* The value is calibrated on the boards.
	*/
	pdata->dphy[2] =
	((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
	\| (((38 * tx_clk_esc) / 1000 - 1) & 0xff);

	dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
	pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
	}

	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;

	pdata = pdev->dev.platform_data;
	if (!pdata)
	return -ENODEV;

	cam = kzalloc(sizeof(*cam), GFP_KERNEL);
	if (cam == NULL)
	return -ENOMEM;
	cam->pdev = pdev;
	cam->mipi_clk = NULL;
	INIT_LIST_HEAD(&cam->devlist);

	mcam = &cam->mcam;
	mcam->plat_power_up = mmpcam_power_up;
	mcam->plat_power_down = mmpcam_power_down;
	mcam->calc_dphy = mmpcam_calc_dphy;
	mcam->dev = &pdev->dev;
	mcam->use_smbus = 0;
	mcam->mclk_min = pdata->mclk_min;
	mcam->mclk_src = pdata->mclk_src;
	mcam->mclk_div = pdata->mclk_div;
	mcam->bus_type = pdata->bus_type;
	mcam->dphy = pdata->dphy;
	mcam->mipi_enabled = false;
	mcam->lane = pdata->lane;
	mcam->chip_id = MCAM_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;
	}
	mcam->regs_size = resource_size(res);
	/*
	* 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.
	*/
	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.
	*/
	ret = mmpcam_power_up(mcam);
	if (ret)
	goto out_gpio2;
	ret = mccic_register(mcam);
	if (ret)
	goto out_pwdn;
	/*
	* 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_pwdn:
	mmpcam_power_down(mcam);
	out_gpio2:
	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);