i2c-mv64xxx.c

linux-2.6.15.6

		rc = IRQ_HANDLED;
	}
	spin_unlock_irqrestore(&drv_data->lock, flags);

	return rc;
}

/*
 *****************************************************************************
 *
 *	I2C Msg Execution Routines
 *
 *****************************************************************************
 */
static void
mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
	struct i2c_msg *msg)
{
	u32	dir = 0;

	drv_data->msg = msg;
	drv_data->byte_posn = 0;
	drv_data->bytes_left = msg->len;
	drv_data->rc = 0;
	drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK |
		MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN;

	if (msg->flags & I2C_M_RD)
		dir = 1;

	if (msg->flags & I2C_M_REV_DIR_ADDR)
		dir ^= 1;

	if (msg->flags & I2C_M_TEN) {
		drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
		drv_data->addr2 = (u32)msg->addr & 0xff;
	} else {
		drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir;
		drv_data->addr2 = 0;
	}
}

static void
mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
{
	long		time_left;
	unsigned long	flags;
	char		abort = 0;

	time_left = wait_event_interruptible_timeout(drv_data->waitq,
		!drv_data->block, msecs_to_jiffies(drv_data->adapter.timeout));

	spin_lock_irqsave(&drv_data->lock, flags);
	if (!time_left) { /* Timed out */
		drv_data->rc = -ETIMEDOUT;
		abort = 1;
	} else if (time_left < 0) { /* Interrupted/Error */
		drv_data->rc = time_left; /* errno value */
		abort = 1;
	}

	if (abort && drv_data->block) {
		drv_data->state = MV64XXX_I2C_STATE_ABORTING;
		spin_unlock_irqrestore(&drv_data->lock, flags);

		time_left = wait_event_timeout(drv_data->waitq,
			!drv_data->block,
			msecs_to_jiffies(drv_data->adapter.timeout));

		if (time_left <= 0) {
			drv_data->state = MV64XXX_I2C_STATE_IDLE;
			dev_err(&drv_data->adapter.dev,
				"mv64xxx: I2C bus locked\n");
		}
	} else
		spin_unlock_irqrestore(&drv_data->lock, flags);
}

static int
mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg)
{
	unsigned long	flags;

	spin_lock_irqsave(&drv_data->lock, flags);
	mv64xxx_i2c_prepare_for_io(drv_data, msg);

	if (unlikely(msg->flags & I2C_M_NOSTART)) { /* Skip start/addr phases */
		if (drv_data->msg->flags & I2C_M_RD) {
			/* No action to do, wait for slave to send a byte */
			drv_data->action = MV64XXX_I2C_ACTION_CONTINUE;
			drv_data->state =
				MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
		} else {
			drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
			drv_data->state =
				MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
			drv_data->bytes_left--;
		}
	} else {
		drv_data->action = MV64XXX_I2C_ACTION_SEND_START;
		drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND;
	}

	drv_data->block = 1;
	mv64xxx_i2c_do_action(drv_data);
	spin_unlock_irqrestore(&drv_data->lock, flags);

	mv64xxx_i2c_wait_for_completion(drv_data);
	return drv_data->rc;
}

/*
 *****************************************************************************
 *
 *	I2C Core Support Routines (Interface to higher level I2C code)
 *
 *****************************************************************************
 */
static u32
mv64xxx_i2c_functionality(struct i2c_adapter *adap)
{
	return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL;
}

static int
mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
	struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
	int	i, rc;

	for (i=0; i<num; i++)
		if ((rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[i])) < 0)
			return rc;

	return num;
}

static struct i2c_algorithm mv64xxx_i2c_algo = {
	.master_xfer = mv64xxx_i2c_xfer,
	.functionality = mv64xxx_i2c_functionality,
};

/*
 *****************************************************************************
 *
 *	Driver Interface & Early Init Routines
 *
 *****************************************************************************
 */
static void __devinit
mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data)
{
	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SOFT_RESET);
	writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)),
		drv_data->reg_base + MV64XXX_I2C_REG_BAUD);
	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SLAVE_ADDR);
	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_EXT_SLAVE_ADDR);
	writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP,
		drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
	drv_data->state = MV64XXX_I2C_STATE_IDLE;
}

static int __devinit
mv64xxx_i2c_map_regs(struct platform_device *pd,
	struct mv64xxx_i2c_data *drv_data)
{
	struct resource	*r;

	if ((r = platform_get_resource(pd, IORESOURCE_MEM, 0)) &&
		request_mem_region(r->start, MV64XXX_I2C_REG_BLOCK_SIZE,
			drv_data->adapter.name)) {

		drv_data->reg_base = ioremap(r->start,
			MV64XXX_I2C_REG_BLOCK_SIZE);
		drv_data->reg_base_p = r->start;
	} else
		return -ENOMEM;

	return 0;
}

static void __devexit
mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data *drv_data)
{
	if (drv_data->reg_base) {
		iounmap(drv_data->reg_base);
		release_mem_region(drv_data->reg_base_p,
			MV64XXX_I2C_REG_BLOCK_SIZE);
	}

	drv_data->reg_base = NULL;
	drv_data->reg_base_p = 0;
}

static int __devinit
mv64xxx_i2c_probe(struct platform_device *pd)
{
	struct mv64xxx_i2c_data		*drv_data;
	struct mv64xxx_i2c_pdata	*pdata = pd->dev.platform_data;
	int	rc;

	if ((pd->id != 0) || !pdata)
		return -ENODEV;

	drv_data = kzalloc(sizeof(struct mv64xxx_i2c_data), GFP_KERNEL);
	if (!drv_data)
		return -ENOMEM;

	if (mv64xxx_i2c_map_regs(pd, drv_data)) {
		rc = -ENODEV;
		goto exit_kfree;
	}

	strncpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter",
		I2C_NAME_SIZE);

	init_waitqueue_head(&drv_data->waitq);
	spin_lock_init(&drv_data->lock);

	drv_data->freq_m = pdata->freq_m;
	drv_data->freq_n = pdata->freq_n;
	drv_data->irq = platform_get_irq(pd, 0);
	drv_data->adapter.id = I2C_HW_MV64XXX;
	drv_data->adapter.algo = &mv64xxx_i2c_algo;
	drv_data->adapter.owner = THIS_MODULE;
	drv_data->adapter.class = I2C_CLASS_HWMON;
	drv_data->adapter.timeout = pdata->timeout;
	drv_data->adapter.retries = pdata->retries;
	platform_set_drvdata(pd, drv_data);
	i2c_set_adapdata(&drv_data->adapter, drv_data);

	if (request_irq(drv_data->irq, mv64xxx_i2c_intr, 0,
			MV64XXX_I2C_CTLR_NAME, drv_data)) {
		dev_err(&drv_data->adapter.dev,
			"mv64xxx: Can't register intr handler irq: %d\n",
			drv_data->irq);
		rc = -EINVAL;
		goto exit_unmap_regs;
	} else if ((rc = i2c_add_adapter(&drv_data->adapter)) != 0) {
		dev_err(&drv_data->adapter.dev,
			"mv64xxx: Can't add i2c adapter, rc: %d\n", -rc);
		goto exit_free_irq;
	}

	mv64xxx_i2c_hw_init(drv_data);

	return 0;

	exit_free_irq:
		free_irq(drv_data->irq, drv_data);
	exit_unmap_regs:
		mv64xxx_i2c_unmap_regs(drv_data);
	exit_kfree:
		kfree(drv_data);
	return rc;
}

static int __devexit
mv64xxx_i2c_remove(struct platform_device *dev)
{
	struct mv64xxx_i2c_data		*drv_data = platform_get_drvdata(dev);
	int	rc;

	rc = i2c_del_adapter(&drv_data->adapter);
	free_irq(drv_data->irq, drv_data);
	mv64xxx_i2c_unmap_regs(drv_data);
	kfree(drv_data);

	return rc;
}

static struct platform_driver mv64xxx_i2c_driver = {
	.probe	= mv64xxx_i2c_probe,
	.remove	= mv64xxx_i2c_remove,
	.driver	= {
		.owner	= THIS_MODULE,
		.name	= MV64XXX_I2C_CTLR_NAME,
	},
};

static int __init
mv64xxx_i2c_init(void)
{
	return platform_driver_register(&mv64xxx_i2c_driver);
}

static void __exit
mv64xxx_i2c_exit(void)
{
	platform_driver_unregister(&mv64xxx_i2c_driver);
}

module_init(mv64xxx_i2c_init);
module_exit(mv64xxx_i2c_exit);

MODULE_AUTHOR("Mark A. Greer <[e-mail]>");
MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver");
MODULE_LICENSE("GPL");