[media] marvell-cam: Separate out the Marvell camera core

There will eventually be multiple users of the core camera controller, so
separate it from the bus/platform/i2c stuff.  I've tried to do the minimal
set of changes to get the driver functioning in this configuration; I did
clean up a bunch of old checkpatch gripes in the process.  This driver
works like the old one did on OLPC XO 1 systems.

Cc: Daniel Drake <dsd@laptop.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/marvell-ccic/Makefile

 obj-$(CONFIG_VIDEO_CAFE_CCIC) += cafe_ccic.o
+cafe_ccic-y := cafe-driver.o mcam-core.o

drivers/media/video/marvell-ccic/cafe-driver.c

+/*
+ * A driver for the CMOS camera controller in the Marvell 88ALP01 "cafe"
+ * multifunction chip.  Currently works with the Omnivision OV7670
+ * sensor.
+ *
+ * The data sheet for this device can be found at:
+ *    http://www.marvell.com/products/pc_connectivity/88alp01/
+ *
+ * Copyright 2006-11 One Laptop Per Child Association, Inc.
+ * Copyright 2006-11 Jonathan Corbet <corbet@lwn.net>
+ *
+ * Written by Jonathan Corbet, corbet@lwn.net.
+ *
+ * v4l2_device/v4l2_subdev conversion by:
+ * Copyright (C) 2009 Hans Verkuil <hverkuil@xs4all.nl>
+ *
+ * Note: this conversion is untested! Please contact the linux-media
+ * mailinglist if you can test this, together with the test results.
+ *
+ * This file may be distributed under the terms of the GNU General
+ * Public License, version 2.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/i2c.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 <linux/device.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+
+#include "mcam-core.h"
+
+#define CAFE_VERSION 0x000002
+
+
+/*
+ * Parameters.
+ */
+MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
+MODULE_DESCRIPTION("Marvell 88ALP01 CMOS Camera Controller driver");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("Video");
+
+
+
+
+struct cafe_camera {
+	int registered;			/* Fully initialized? */
+	struct mcam_camera mcam;
+	struct pci_dev *pdev;
+	wait_queue_head_t smbus_wait;	/* Waiting on i2c events */
+};
+
+/*
+ * Debugging and related.
+ */
+#define cam_err(cam, fmt, arg...) \
+	dev_err(&(cam)->pdev->dev, fmt, ##arg);
+#define cam_warn(cam, fmt, arg...) \
+	dev_warn(&(cam)->pdev->dev, fmt, ##arg);
+
+/* -------------------------------------------------------------------- */
+/*
+ * The I2C/SMBUS interface to the camera itself starts here.  The
+ * controller handles SMBUS itself, presenting a relatively simple register
+ * interface; all we have to do is to tell it where to route the data.
+ */
+#define CAFE_SMBUS_TIMEOUT (HZ)  /* generous */
+
+static inline struct cafe_camera *to_cam(struct v4l2_device *dev)
+{
+	struct mcam_camera *m = container_of(dev, struct mcam_camera, v4l2_dev);
+	return container_of(m, struct cafe_camera, mcam);
+}
+
+
+static int cafe_smbus_write_done(struct mcam_camera *mcam)
+{
+	unsigned long flags;
+	int c1;
+
+	/*
+	 * We must delay after the interrupt, or the controller gets confused
+	 * and never does give us good status.  Fortunately, we don't do this
+	 * often.
+	 */
+	udelay(20);
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	c1 = mcam_reg_read(mcam, REG_TWSIC1);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+	return (c1 & (TWSIC1_WSTAT|TWSIC1_ERROR)) != TWSIC1_WSTAT;
+}
+
+static int cafe_smbus_write_data(struct cafe_camera *cam,
+		u16 addr, u8 command, u8 value)
+{
+	unsigned int rval;
+	unsigned long flags;
+	struct mcam_camera *mcam = &cam->mcam;
+
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	rval = TWSIC0_EN | ((addr << TWSIC0_SID_SHIFT) & TWSIC0_SID);
+	rval |= TWSIC0_OVMAGIC;  /* Make OV sensors work */
+	/*
+	 * Marvell sez set clkdiv to all 1's for now.
+	 */
+	rval |= TWSIC0_CLKDIV;
+	mcam_reg_write(mcam, REG_TWSIC0, rval);
+	(void) mcam_reg_read(mcam, REG_TWSIC1); /* force write */
+	rval = value | ((command << TWSIC1_ADDR_SHIFT) & TWSIC1_ADDR);
+	mcam_reg_write(mcam, REG_TWSIC1, rval);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+
+	/* Unfortunately, reading TWSIC1 too soon after sending a command
+	 * causes the device to die.
+	 * Use a busy-wait because we often send a large quantity of small
+	 * commands at-once; using msleep() would cause a lot of context
+	 * switches which take longer than 2ms, resulting in a noticeable
+	 * boot-time and capture-start delays.
+	 */
+	mdelay(2);
+
+	/*
+	 * Another sad fact is that sometimes, commands silently complete but
+	 * cafe_smbus_write_done() never becomes aware of this.
+	 * This happens at random and appears to possible occur with any
+	 * command.
+	 * We don't understand why this is. We work around this issue
+	 * with the timeout in the wait below, assuming that all commands
+	 * complete within the timeout.
+	 */
+	wait_event_timeout(cam->smbus_wait, cafe_smbus_write_done(mcam),
+			CAFE_SMBUS_TIMEOUT);
+
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	rval = mcam_reg_read(mcam, REG_TWSIC1);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+
+	if (rval & TWSIC1_WSTAT) {
+		cam_err(cam, "SMBUS write (%02x/%02x/%02x) timed out\n", addr,
+				command, value);
+		return -EIO;
+	}
+	if (rval & TWSIC1_ERROR) {
+		cam_err(cam, "SMBUS write (%02x/%02x/%02x) error\n", addr,
+				command, value);
+		return -EIO;
+	}
+	return 0;
+}
+
+
+
+static int cafe_smbus_read_done(struct mcam_camera *mcam)
+{
+	unsigned long flags;
+	int c1;
+
+	/*
+	 * We must delay after the interrupt, or the controller gets confused
+	 * and never does give us good status.  Fortunately, we don't do this
+	 * often.
+	 */
+	udelay(20);
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	c1 = mcam_reg_read(mcam, REG_TWSIC1);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+	return c1 & (TWSIC1_RVALID|TWSIC1_ERROR);
+}
+
+
+
+static int cafe_smbus_read_data(struct cafe_camera *cam,
+		u16 addr, u8 command, u8 *value)
+{
+	unsigned int rval;
+	unsigned long flags;
+	struct mcam_camera *mcam = &cam->mcam;
+
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	rval = TWSIC0_EN | ((addr << TWSIC0_SID_SHIFT) & TWSIC0_SID);
+	rval |= TWSIC0_OVMAGIC; /* Make OV sensors work */
+	/*
+	 * Marvel sez set clkdiv to all 1's for now.
+	 */
+	rval |= TWSIC0_CLKDIV;
+	mcam_reg_write(mcam, REG_TWSIC0, rval);
+	(void) mcam_reg_read(mcam, REG_TWSIC1); /* force write */
+	rval = TWSIC1_READ | ((command << TWSIC1_ADDR_SHIFT) & TWSIC1_ADDR);
+	mcam_reg_write(mcam, REG_TWSIC1, rval);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+
+	wait_event_timeout(cam->smbus_wait,
+			cafe_smbus_read_done(mcam), CAFE_SMBUS_TIMEOUT);
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	rval = mcam_reg_read(mcam, REG_TWSIC1);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+
+	if (rval & TWSIC1_ERROR) {
+		cam_err(cam, "SMBUS read (%02x/%02x) error\n", addr, command);
+		return -EIO;
+	}
+	if (!(rval & TWSIC1_RVALID)) {
+		cam_err(cam, "SMBUS read (%02x/%02x) timed out\n", addr,
+				command);
+		return -EIO;
+	}
+	*value = rval & 0xff;
+	return 0;
+}
+
+/*
+ * Perform a transfer over SMBUS.  This thing is called under
+ * the i2c bus lock, so we shouldn't race with ourselves...
+ */
+static int cafe_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
+		unsigned short flags, char rw, u8 command,
+		int size, union i2c_smbus_data *data)
+{
+	struct cafe_camera *cam = i2c_get_adapdata(adapter);
+	int ret = -EINVAL;
+
+	/*
+	 * This interface would appear to only do byte data ops.  OK
+	 * it can do word too, but the cam chip has no use for that.
+	 */
+	if (size != I2C_SMBUS_BYTE_DATA) {
+		cam_err(cam, "funky xfer size %d\n", size);
+		return -EINVAL;
+	}
+
+	if (rw == I2C_SMBUS_WRITE)
+		ret = cafe_smbus_write_data(cam, addr, command, data->byte);
+	else if (rw == I2C_SMBUS_READ)
+		ret = cafe_smbus_read_data(cam, addr, command, &data->byte);
+	return ret;
+}
+
+
+static void cafe_smbus_enable_irq(struct cafe_camera *cam)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cam->mcam.dev_lock, flags);
+	mcam_reg_set_bit(&cam->mcam, REG_IRQMASK, TWSIIRQS);
+	spin_unlock_irqrestore(&cam->mcam.dev_lock, flags);
+}
+
+static u32 cafe_smbus_func(struct i2c_adapter *adapter)
+{
+	return I2C_FUNC_SMBUS_READ_BYTE_DATA  |
+	       I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+}
+
+static struct i2c_algorithm cafe_smbus_algo = {
+	.smbus_xfer = cafe_smbus_xfer,
+	.functionality = cafe_smbus_func
+};
+
+static int cafe_smbus_setup(struct cafe_camera *cam)
+{
+	struct i2c_adapter *adap = &cam->mcam.i2c_adapter;
+	int ret;
+
+	cafe_smbus_enable_irq(cam);
+	adap->owner = THIS_MODULE;
+	adap->algo = &cafe_smbus_algo;
+	strcpy(adap->name, "cafe_ccic");
+	adap->dev.parent = &cam->pdev->dev;
+	i2c_set_adapdata(adap, cam);
+	ret = i2c_add_adapter(adap);
+	if (ret)
+		printk(KERN_ERR "Unable to register cafe i2c adapter\n");
+	return ret;
+}
+
+static void cafe_smbus_shutdown(struct cafe_camera *cam)
+{
+	i2c_del_adapter(&cam->mcam.i2c_adapter);
+}
+
+
+/*
+ * Controller-level stuff
+ */
+
+static void cafe_ctlr_init(struct mcam_camera *mcam)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+	/*
+	 * Added magic to bring up the hardware on the B-Test board
+	 */
+	mcam_reg_write(mcam, 0x3038, 0x8);
+	mcam_reg_write(mcam, 0x315c, 0x80008);
+	/*
+	 * Go through the dance needed to wake the device up.
+	 * Note that these registers are global and shared
+	 * with the NAND and SD devices.  Interaction between the
+	 * three still needs to be examined.
+	 */
+	mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRS|GCSR_MRS); /* Needed? */
+	mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRC|GCSR_MRC);
+	mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRC|GCSR_MRS);
+	/*
+	 * Here we must wait a bit for the controller to come around.
+	 */
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+	msleep(5);
+	spin_lock_irqsave(&mcam->dev_lock, flags);
+
+	mcam_reg_write(mcam, REG_GL_CSR, GCSR_CCIC_EN|GCSR_SRC|GCSR_MRC);
+	mcam_reg_set_bit(mcam, REG_GL_IMASK, GIMSK_CCIC_EN);
+	/*
+	 * Mask all interrupts.
+	 */
+	mcam_reg_write(mcam, REG_IRQMASK, 0);
+	spin_unlock_irqrestore(&mcam->dev_lock, flags);
+}
+
+
+static void cafe_ctlr_power_up(struct mcam_camera *mcam)
+{
+	/*
+	 * Part one of the sensor dance: turn the global
+	 * GPIO signal on.
+	 */
+	mcam_reg_write(mcam, REG_GL_FCR, GFCR_GPIO_ON);
+	mcam_reg_write(mcam, REG_GL_GPIOR, GGPIO_OUT|GGPIO_VAL);
+	/*
+	 * Put the sensor into operational mode (assumes OLPC-style
+	 * wiring).  Control 0 is reset - set to 1 to operate.
+	 * Control 1 is power down, set to 0 to operate.
+	 */
+	mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN); /* pwr up, reset */
+	mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C0);
+}
+
+static void cafe_ctlr_power_down(struct mcam_camera *mcam)
+{
+	mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C1);
+	mcam_reg_write(mcam, REG_GL_FCR, GFCR_GPIO_ON);
+	mcam_reg_write(mcam, REG_GL_GPIOR, GGPIO_OUT);
+}
+
+
+
+/*
+ * The platform interrupt handler.
+ */
+static irqreturn_t cafe_irq(int irq, void *data)
+{
+	struct cafe_camera *cam = data;
+	struct mcam_camera *mcam = &cam->mcam;
+	unsigned int irqs, handled;
+
+	spin_lock(&mcam->dev_lock);
+	irqs = mcam_reg_read(mcam, REG_IRQSTAT);
+	handled = cam->registered && mccic_irq(mcam, irqs);
+	if (irqs & TWSIIRQS) {
+		mcam_reg_write(mcam, REG_IRQSTAT, TWSIIRQS);
+		wake_up(&cam->smbus_wait);
+		handled = 1;
+	}
+	spin_unlock(&mcam->dev_lock);
+	return IRQ_RETVAL(handled);
+}
+
+
+/* -------------------------------------------------------------------------- */
+/*
+ * PCI interface stuff.
+ */
+
+static int cafe_pci_probe(struct pci_dev *pdev,
+		const struct pci_device_id *id)
+{
+	int ret;
+	struct cafe_camera *cam;
+	struct mcam_camera *mcam;
+
+	/*
+	 * Start putting together one of our big camera structures.
+	 */
+	ret = -ENOMEM;
+	cam = kzalloc(sizeof(struct cafe_camera), GFP_KERNEL);
+	if (cam == NULL)
+		goto out;
+	cam->pdev = pdev;
+	mcam = &cam->mcam;
+	mcam->chip_id = V4L2_IDENT_CAFE;
+	spin_lock_init(&mcam->dev_lock);
+	init_waitqueue_head(&cam->smbus_wait);
+	mcam->plat_power_up = cafe_ctlr_power_up;
+	mcam->plat_power_down = cafe_ctlr_power_down;
+	mcam->dev = &pdev->dev;
+	/*
+	 * Get set up on the PCI bus.
+	 */
+	ret = pci_enable_device(pdev);
+	if (ret)
+		goto out_free;
+	pci_set_master(pdev);
+
+	ret = -EIO;
+	mcam->regs = pci_iomap(pdev, 0, 0);
+	if (!mcam->regs) {
+		printk(KERN_ERR "Unable to ioremap cafe-ccic regs\n");
+		goto out_disable;
+	}
+	ret = request_irq(pdev->irq, cafe_irq, IRQF_SHARED, "cafe-ccic", cam);
+	if (ret)
+		goto out_iounmap;
+
+	/*
+	 * Initialize the controller and leave it powered up.  It will
+	 * stay that way until the sensor driver shows up.
+	 */
+	cafe_ctlr_init(mcam);
+	cafe_ctlr_power_up(mcam);
+	/*
+	 * Set up I2C/SMBUS communications.  We have to drop the mutex here
+	 * because the sensor could attach in this call chain, leading to
+	 * unsightly deadlocks.
+	 */
+	ret = cafe_smbus_setup(cam);
+	if (ret)
+		goto out_pdown;
+
+	ret = mccic_register(mcam);
+	if (ret == 0) {
+		cam->registered = 1;
+		return 0;
+	}
+
+	cafe_smbus_shutdown(cam);
+out_pdown:
+	cafe_ctlr_power_down(mcam);
+	free_irq(pdev->irq, cam);
+out_iounmap:
+	pci_iounmap(pdev, mcam->regs);
+out_disable:
+	pci_disable_device(pdev);
+out_free:
+	kfree(cam);
+out:
+	return ret;
+}
+
+
+/*
+ * Shut down an initialized device
+ */
+static void cafe_shutdown(struct cafe_camera *cam)
+{
+	mccic_shutdown(&cam->mcam);
+	cafe_smbus_shutdown(cam);
+	free_irq(cam->pdev->irq, cam);
+	pci_iounmap(cam->pdev, cam->mcam.regs);
+}
+
+
+static void cafe_pci_remove(struct pci_dev *pdev)
+{
+	struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
+	struct cafe_camera *cam = to_cam(v4l2_dev);
+
+	if (cam == NULL) {
+		printk(KERN_WARNING "pci_remove on unknown pdev %p\n", pdev);
+		return;
+	}
+	cafe_shutdown(cam);
+	kfree(cam);
+}
+
+
+#ifdef CONFIG_PM
+/*
+ * Basic power management.
+ */
+static int cafe_pci_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
+	struct cafe_camera *cam = to_cam(v4l2_dev);
+	int ret;
+
+	ret = pci_save_state(pdev);
+	if (ret)
+		return ret;
+	mccic_suspend(&cam->mcam);
+	pci_disable_device(pdev);
+	return 0;
+}
+
+
+static int cafe_pci_resume(struct pci_dev *pdev)
+{
+	struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
+	struct cafe_camera *cam = to_cam(v4l2_dev);
+	int ret = 0;
+
+	pci_restore_state(pdev);
+	ret = pci_enable_device(pdev);
+
+	if (ret) {
+		cam_warn(cam, "Unable to re-enable device on resume!\n");
+		return ret;
+	}
+	cafe_ctlr_init(&cam->mcam);
+	return mccic_resume(&cam->mcam);
+}
+
+#endif  /* CONFIG_PM */
+
+static struct pci_device_id cafe_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_MARVELL,
+		     PCI_DEVICE_ID_MARVELL_88ALP01_CCIC) },
+	{ 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, cafe_ids);
+
+static struct pci_driver cafe_pci_driver = {
+	.name = "cafe1000-ccic",
+	.id_table = cafe_ids,
+	.probe = cafe_pci_probe,
+	.remove = cafe_pci_remove,
+#ifdef CONFIG_PM
+	.suspend = cafe_pci_suspend,
+	.resume = cafe_pci_resume,
+#endif
+};
+
+
+
+
+static int __init cafe_init(void)
+{
+	int ret;
+
+	printk(KERN_NOTICE "Marvell M88ALP01 'CAFE' Camera Controller version %d\n",
+			CAFE_VERSION);
+	ret = pci_register_driver(&cafe_pci_driver);
+	if (ret) {
+		printk(KERN_ERR "Unable to register cafe_ccic driver\n");
+		goto out;
+	}
+	ret = 0;
+
+out:
+	return ret;
+}
+
+
+static void __exit cafe_exit(void)
+{
+	pci_unregister_driver(&cafe_pci_driver);
+}
+
+module_init(cafe_init);
+module_exit(cafe_exit);

drivers/media/video/marvell-ccic/cafe_ccic-regs.h → drivers/media/video/marvell-ccic/mcam-core.h

+/*
+ * Marvell camera core structures.
+ *
+ * Copyright 2011 Jonathan Corbet corbet@lwn.net
+ */
+
+/*
+ * Tracking of streaming I/O buffers.
+ * FIXME doesn't belong in this file
+ */
+struct mcam_sio_buffer {
+	struct list_head list;
+	struct v4l2_buffer v4lbuf;
+	char *buffer;   /* Where it lives in kernel space */
+	int mapcount;
+	struct mcam_camera *cam;
+};
+
+enum mcam_state {
+	S_NOTREADY,	/* Not yet initialized */
+	S_IDLE,		/* Just hanging around */
+	S_FLAKED,	/* Some sort of problem */
+	S_SINGLEREAD,	/* In read() */
+	S_SPECREAD,	/* Speculative read (for future read()) */
+	S_STREAMING	/* Streaming data */
+};
+#define MAX_DMA_BUFS 3
+
+/*
+ * A description of one of our devices.
+ * Locking: controlled by s_mutex.  Certain fields, however, require
+ *          the dev_lock spinlock; they are marked as such by comments.
+ *          dev_lock is also required for access to device registers.
+ */
+struct mcam_camera {
+	/*
+	 * These fields should be set by the platform code prior to
+	 * calling mcam_register().
+	 */
+	struct i2c_adapter i2c_adapter;
+	unsigned char __iomem *regs;
+	spinlock_t dev_lock;
+	struct device *dev; /* For messages, dma alloc */
+	unsigned int chip_id;
+
+	/*
+	 * Callbacks from the core to the platform code.
+	 */
+	void (*plat_power_up) (struct mcam_camera *cam);
+	void (*plat_power_down) (struct mcam_camera *cam);
+
+	/*
+	 * Everything below here is private to the mcam core and
+	 * should not be touched by the platform code.
+	 */
+	struct v4l2_device v4l2_dev;
+	enum mcam_state state;
+	unsigned long flags;		/* Buffer status, mainly (dev_lock) */
+	int users;			/* How many open FDs */
+	struct file *owner;		/* Who has data access (v4l2) */
+
+	/*
+	 * Subsystem structures.
+	 */
+	struct video_device vdev;
+	struct v4l2_subdev *sensor;
+	unsigned short sensor_addr;
+
+	struct list_head dev_list;	/* link to other devices */
+
+	/* DMA buffers */
+	unsigned int nbufs;		/* How many are alloc'd */
+	int next_buf;			/* Next to consume (dev_lock) */
+	unsigned int dma_buf_size;	/* allocated size */
+	void *dma_bufs[MAX_DMA_BUFS];	/* Internal buffer addresses */
+	dma_addr_t dma_handles[MAX_DMA_BUFS]; /* Buffer bus addresses */
+	unsigned int specframes;	/* Unconsumed spec frames (dev_lock) */
+	unsigned int sequence;		/* Frame sequence number */
+	unsigned int buf_seq[MAX_DMA_BUFS]; /* Sequence for individual buffers */
+
+	/* Streaming buffers */
+	unsigned int n_sbufs;		/* How many we have */
+	struct mcam_sio_buffer *sb_bufs; /* The array of housekeeping structs */
+	struct list_head sb_avail;	/* Available for data (we own) (dev_lock) */
+	struct list_head sb_full;	/* With data (user space owns) (dev_lock) */
+	struct tasklet_struct s_tasklet;
+
+	/* Current operating parameters */
+	u32 sensor_type;		/* Currently ov7670 only */
+	struct v4l2_pix_format pix_format;
+	enum v4l2_mbus_pixelcode mbus_code;
+
+	/* Locks */
+	struct mutex s_mutex; /* Access to this structure */
+
+	/* Misc */
+	wait_queue_head_t iowait;	/* Waiting on frame data */
+};
+
+
+/*
+ * Register I/O functions.  These are here because the platform code
+ * may legitimately need to mess with the register space.
+ */
+/*
+ * Device register I/O
+ */
+static inline void mcam_reg_write(struct mcam_camera *cam, unsigned int reg,
+		unsigned int val)
+{
+	iowrite32(val, cam->regs + reg);
+}
+
+static inline unsigned int mcam_reg_read(struct mcam_camera *cam,
+		unsigned int reg)
+{
+	return ioread32(cam->regs + reg);
+}
+
+
+static inline void mcam_reg_write_mask(struct mcam_camera *cam, unsigned int reg,
+		unsigned int val, unsigned int mask)
+{
+	unsigned int v = mcam_reg_read(cam, reg);
+
+	v = (v & ~mask) | (val & mask);
+	mcam_reg_write(cam, reg, v);
+}
+
+static inline void mcam_reg_clear_bit(struct mcam_camera *cam,
+		unsigned int reg, unsigned int val)
+{
+	mcam_reg_write_mask(cam, reg, 0, val);
+}
+
+static inline void mcam_reg_set_bit(struct mcam_camera *cam,
+		unsigned int reg, unsigned int val)
+{
+	mcam_reg_write_mask(cam, reg, val, val);
+}
+
+/*
+ * Functions for use by platform code.
+ */
+int mccic_register(struct mcam_camera *cam);
+int mccic_irq(struct mcam_camera *cam, unsigned int irqs);
+void mccic_shutdown(struct mcam_camera *cam);
+#ifdef CONFIG_PM
+void mccic_suspend(struct mcam_camera *cam);
+int mccic_resume(struct mcam_camera *cam);
+#endif
+
 /*
  * Register definitions for the m88alp01 camera interface.  Offsets in bytes
  * as given in the spec.
- *
- * Copyright 2006 One Laptop Per Child Association, Inc.
- *
- * Written by Jonathan Corbet, corbet@lwn.net.
- *
- * This file may be distributed under the terms of the GNU General
- * Public License, version 2.
  */
 #define REG_Y0BAR	0x00
 #define REG_Y1BAR	0x04
@@ -156,7 +301,7 @@
 #define	  GGPIO_OUT		0x80000	/* GPIO output */
 #define	  GGPIO_VAL		0x00008	/* Output pin value */
 
-#define REG_LEN                REG_GL_IMASK + 4
+#define REG_LEN		       (REG_GL_IMASK + 4)
 
 
 /*