Commit 1ecac07a authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
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i2c-algo-bit: Always send a stop condition before leaving 



The i2c-algo-bit driver doesn't behave well on read errors: it'll
bail out without even sending a stop condition on the bus, so the bus
will be stuck. So make sure that we always send a stop condition on
the bus before we leave. The best way to make sure is to always send
it at the end of function bit_xfer.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent ef2c8321

drivers/i2c/algos/i2c-algo-bit.c

+15 −12
Original line number Diff line number Diff line
@@ -312,12 +312,10 @@ static int try_address(struct i2c_adapter *i2c_adap, 
	int i,ret = -1;

	for (i=0;i<=retries;i++) {

		ret = i2c_outb(i2c_adap,addr);

		if (ret==1)

			break;	/* success! */

		if (ret == 1 || i == retries)

			break;

		i2c_stop(adap);

		udelay(5/*adap->udelay*/);

		if (i==retries)  /* no success */

			break;

		i2c_start(adap);

		udelay(adap->udelay);

	}
@@ -331,7 +329,6 @@ static int try_address(struct i2c_adapter *i2c_adap, 


static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)

{

	struct i2c_algo_bit_data *adap = i2c_adap->algo_data;

	char c;

	const char *temp = msg->buf;

	int count = msg->len;
@@ -349,7 +346,6 @@ static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) 
			wrcount++;

		} else { /* arbitration or no acknowledge */

			dev_err(&i2c_adap->dev, "sendbytes: error - bailout.\n");

			i2c_stop(adap);

			return (retval<0)? retval : -EFAULT;

			        /* got a better one ?? */

		}
@@ -480,7 +476,7 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, 
			if ((ret != 0) && !nak_ok) {

			    DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: NAK from device addr %2.2x msg #%d\n"

					,msgs[i].addr,i));

			    return (ret<0) ? ret : -EREMOTEIO;

				goto bailout;

			}

		}

		if (pmsg->flags & I2C_M_RD ) {
@@ -488,19 +484,26 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, 
			ret = readbytes(i2c_adap, pmsg);

			DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: read %d bytes.\n",ret));

			if (ret < pmsg->len) {

				return (ret<0)? ret : -EREMOTEIO;

				if (ret >= 0)

					ret = -EREMOTEIO;

				goto bailout;

			}

		} else {

			/* write bytes from buffer */

			ret = sendbytes(i2c_adap, pmsg);

			DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: wrote %d bytes.\n",ret));

			if (ret < pmsg->len) {

				return (ret<0) ? ret : -EREMOTEIO;

				if (ret >= 0)

					ret = -EREMOTEIO;

				goto bailout;

			}

		}

	}

	ret = i;



bailout:

	i2c_stop(adap);

	return num;

	return ret;

}



static u32 bit_func(struct i2c_adapter *adap)

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