forked from Minki/linux
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: Jean Delvare <khali@linux-fr.org>
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@ -312,12 +312,10 @@ static int try_address(struct i2c_adapter *i2c_adap,
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int i,ret = -1;
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for (i=0;i<=retries;i++) {
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ret = i2c_outb(i2c_adap,addr);
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if (ret==1)
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break; /* success! */
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if (ret == 1 || i == retries)
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break;
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i2c_stop(adap);
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udelay(5/*adap->udelay*/);
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if (i==retries) /* no success */
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break;
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i2c_start(adap);
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udelay(adap->udelay);
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}
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@ -331,7 +329,6 @@ static int try_address(struct i2c_adapter *i2c_adap,
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static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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{
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struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
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char c;
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const char *temp = msg->buf;
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int count = msg->len;
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@ -349,7 +346,6 @@ static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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wrcount++;
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} else { /* arbitration or no acknowledge */
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dev_err(&i2c_adap->dev, "sendbytes: error - bailout.\n");
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i2c_stop(adap);
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return (retval<0)? retval : -EFAULT;
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/* got a better one ?? */
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}
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@ -480,27 +476,34 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
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if ((ret != 0) && !nak_ok) {
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DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: NAK from device addr %2.2x msg #%d\n"
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,msgs[i].addr,i));
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return (ret<0) ? ret : -EREMOTEIO;
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goto bailout;
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}
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}
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if (pmsg->flags & I2C_M_RD ) {
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/* read bytes into buffer*/
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ret = readbytes(i2c_adap, pmsg);
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DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: read %d bytes.\n",ret));
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if (ret < pmsg->len ) {
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return (ret<0)? ret : -EREMOTEIO;
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if (ret < pmsg->len) {
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if (ret >= 0)
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ret = -EREMOTEIO;
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goto bailout;
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}
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} else {
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/* write bytes from buffer */
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ret = sendbytes(i2c_adap, pmsg);
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DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: wrote %d bytes.\n",ret));
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if (ret < pmsg->len ) {
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return (ret<0) ? ret : -EREMOTEIO;
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if (ret < pmsg->len) {
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if (ret >= 0)
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ret = -EREMOTEIO;
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goto bailout;
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}
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}
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}
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ret = i;
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bailout:
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i2c_stop(adap);
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return num;
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return ret;
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}
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static u32 bit_func(struct i2c_adapter *adap)
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