Commit bd4217d8 authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
Browse files

i2c-dev: Unbound new-style i2c clients aren't busy 



Let i2c-dev deal properly with new-style i2c clients. Instead of
considering them always busy, it needs to check wether a driver is
bound to them or not.

This is still not completely correct, as the client could become
busy later, but the same problem already existed before new-style
clients were introduced. We'll want to fix it someday.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Acked-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
parent 907135aa

drivers/i2c/i2c-dev.c

+25 −1
Original line number Diff line number Diff line
@@ -182,6 +182,29 @@ static ssize_t i2cdev_write (struct file *file, const char __user *buf, size_t c 
	return ret;

}



/* This address checking function differs from the one in i2c-core

   in that it considers an address with a registered device, but no

   bounded driver, as NOT busy. */

static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)

{

	struct list_head *item;

	struct i2c_client *client;

	int res = 0;



	mutex_lock(&adapter->clist_lock);

	list_for_each(item, &adapter->clients) {

		client = list_entry(item, struct i2c_client, list);

		if (client->addr == addr) {

			if (client->driver)

				res = -EBUSY;

			break;

		}

	}

	mutex_unlock(&adapter->clist_lock);



	return res;

}



static int i2cdev_ioctl(struct inode *inode, struct file *file,

		unsigned int cmd, unsigned long arg)

{
@@ -213,8 +236,9 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file, 
		if ((arg > 0x3ff) ||

		    (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))

			return -EINVAL;

		if ((cmd == I2C_SLAVE) && i2c_check_addr(client->adapter,arg))

		if (cmd == I2C_SLAVE && i2cdev_check_addr(client->adapter, arg))

			return -EBUSY;

		/* REVISIT: address could become busy later */

		client->addr = arg;

		return 0;

	case I2C_TENBIT:

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