- 根目录:
- drivers
- media
- platform
- 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>
*
* 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 */
};
/*
* Most of the camera controller registers are defined in mcam-core.h,
* but the Cafe platform has some additional registers of its own;
* they are described here.
*/
/*
* "General purpose register" has a couple of GPIOs used for sensor
* power and reset on OLPC XO 1.0 systems.
*/
#define REG_GPR 0xb4
#define GPR_C1EN 0x00000020 /* Pad 1 (power down) enable */
#define GPR_C0EN 0x00000010 /* Pad 0 (reset) enable */
#define GPR_C1 0x00000002 /* Control 1 value */
/*
* Control 0 is wired to reset on OLPC machines. For ov7x sensors,
* it is active low.
*/
#define GPR_C0 0x00000001 /* Control 0 value */
/*
* These registers control the SMBUS module for communicating
* with the sensor.
*/
#define REG_TWSIC0 0xb8 /* TWSI (smbus) control 0 */
#define TWSIC0_EN 0x00000001 /* TWSI enable */
#define TWSIC0_MODE 0x00000002 /* 1 = 16-bit, 0 = 8-bit */
#define TWSIC0_SID 0x000003fc /* Slave ID */
/*
* Subtle trickery: the slave ID field starts with bit 2. But the
* Linux i2c stack wants to treat the bottommost bit as a separate
* read/write bit, which is why slave ID's are usually presented
* >>1. For consistency with that behavior, we shift over three
* bits instead of two.
*/
#define TWSIC0_SID_SHIFT 3
#define TWSIC0_CLKDIV 0x0007fc00 /* Clock divider */
#define TWSIC0_MASKACK 0x00400000 /* Mask ack from sensor */
#define TWSIC0_OVMAGIC 0x00800000 /* Make it work on OV sensors */
#define REG_TWSIC1 0xbc /* TWSI control 1 */
#define TWSIC1_DATA 0x0000ffff /* Data to/from camchip */
#define TWSIC1_ADDR 0x00ff0000 /* Address (register) */
#define TWSIC1_ADDR_SHIFT 16
#define TWSIC1_READ 0x01000000 /* Set for read op */
#define TWSIC1_WSTAT 0x02000000 /* Write status */
#define TWSIC1_RVALID 0x04000000 /* Read data valid */
#define TWSIC1_ERROR 0x08000000 /* Something screwed up */
/*
* Here's the weird global control registers
*/
#define REG_GL_CSR 0x3004 /* Control/status register */
#define GCSR_SRS 0x00000001 /* SW Reset set */
#define GCSR_SRC 0x00000002 /* SW Reset clear */
#define GCSR_MRS 0x00000004 /* Master reset set */
#define GCSR_MRC 0x00000008 /* HW Reset clear */
#define GCSR_CCIC_EN 0x00004000 /* CCIC Clock enable */
#define REG_GL_IMASK 0x300c /* Interrupt mask register */
#define GIMSK_CCIC_EN 0x00000004 /* CCIC Interrupt enable */
#define REG_GL_FCR 0x3038 /* GPIO functional control register */
#define GFCR_GPIO_ON 0x08 /* Camera GPIO enabled */
#define REG_GL_GPIOR 0x315c /* GPIO register */
#define GGPIO_OUT 0x80000 /* GPIO output */
#define GGPIO_VAL 0x00008 /* Output pin value */
#define REG_LEN (REG_GL_IMASK + 4)
/*
* 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;
int ret;
adap = kzalloc(sizeof(*adap), GFP_KERNEL);
if (adap == NULL)
return -ENOMEM;
cam->mcam.i2c_adapter = adap;
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);
kfree(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;
/*
* Set the clock speed for the XO 1; I don't believe this
* driver has ever run anywhere else.
*/
mcam->clock_speed = 45;
mcam->use_smbus = 1;
/*
* Vmalloc mode for buffers is traditional with this driver.
* We *might* be able to run DMA_contig, especially on a system
* with CMA in it.
*/
mcam->buffer_mode = B_vmalloc;
/*
* 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);