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[media] em28xx-i2c: Fix error code for I2C error transfers

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Follow the error codes for I2C as described at Documentation/i2c/fault-codes.

In the case of the I2C status register (0x05), this is mapped into:

	- ENXIO - when reg 05 returns 0x10
	- ETIMEDOUT - when the device is not temporarily not responding
		      (e. g. reg 05 returning something not 0x10 or 0x00)
	- EIO - for generic I/O errors that don't fit into the above.

In the specific case of 0-byte reads, used only during I2C device
probing, it keeps returning -ENODEV.

TODO: return EBUSY when reg 05 returns 0x20 on em2874 and upper.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Mauro Carvalho Chehab 2014-01-04 05:42:11 -03:00
parent d20e4ed6d3
commit e63b009d6e
1 changed files with 20 additions and 17 deletions
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37
drivers/media/usb/em28xx/em28xx-i2c.c
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@ -80,7 +80,7 @@ static int em2800_i2c_send_bytes(struct em28xx *dev, u8 addr, u8 *buf, u16 len)
if (ret == 0x80 + len - 1) if (ret == 0x80 + len - 1)
return len; return len;
if (ret == 0x94 + len - 1) { if (ret == 0x94 + len - 1) {
return -ENODEV; return -ENXIO;
} }
if (ret < 0) { if (ret < 0) {
em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n", em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n",
@ -90,7 +90,7 @@ static int em2800_i2c_send_bytes(struct em28xx *dev, u8 addr, u8 *buf, u16 len)
msleep(5); msleep(5);
} }
em28xx_warn("write to i2c device at 0x%x timed out\n", addr); em28xx_warn("write to i2c device at 0x%x timed out\n", addr);
return -EIO; return -ETIMEDOUT;
} }
/* /*
@ -123,7 +123,7 @@ static int em2800_i2c_recv_bytes(struct em28xx *dev, u8 addr, u8 *buf, u16 len)
if (ret == 0x84 + len - 1) if (ret == 0x84 + len - 1)
break; break;
if (ret == 0x94 + len - 1) { if (ret == 0x94 + len - 1) {
return -ENODEV; return -ENXIO;
} }
if (ret < 0) { if (ret < 0) {
em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n", em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n",
@ -199,7 +199,7 @@ static int em28xx_i2c_send_bytes(struct em28xx *dev, u16 addr, u8 *buf,
if (ret == 0) /* success */ if (ret == 0) /* success */
return len; return len;
if (ret == 0x10) { if (ret == 0x10) {
return -ENODEV; return -ENXIO;
} }
if (ret < 0) { if (ret < 0) {
em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n", em28xx_warn("failed to get i2c transfer status from bridge register (error=%i)\n",
@ -213,9 +213,8 @@ static int em28xx_i2c_send_bytes(struct em28xx *dev, u16 addr, u8 *buf,
* (even with high payload) ... * (even with high payload) ...
*/ */
} }
em28xx_warn("write to i2c device at 0x%x timed out (status=%i)\n", addr, ret);
em28xx_warn("write to i2c device at 0x%x timed out\n", addr); return -ETIMEDOUT;
return -EIO;
} }
/* /*
@ -245,7 +244,7 @@ static int em28xx_i2c_recv_bytes(struct em28xx *dev, u16 addr, u8 *buf, u16 len)
* bytes if we are on bus B AND there was no write attempt to the * bytes if we are on bus B AND there was no write attempt to the
* specified slave address before AND no device is present at the * specified slave address before AND no device is present at the
* requested slave address. * requested slave address.
* Anyway, the next check will fail with -ENODEV in this case, so avoid * Anyway, the next check will fail with -ENXIO in this case, so avoid
* spamming the system log on device probing and do nothing here. * spamming the system log on device probing and do nothing here.
*/ */
@ -259,10 +258,10 @@ static int em28xx_i2c_recv_bytes(struct em28xx *dev, u16 addr, u8 *buf, u16 len)
return ret; return ret;
} }
if (ret == 0x10) if (ret == 0x10)
return -ENODEV; return -ENXIO;
em28xx_warn("unknown i2c error (status=%i)\n", ret); em28xx_warn("unknown i2c error (status=%i)\n", ret);
return -EIO; return -ETIMEDOUT;
} }
/* /*
@ -318,7 +317,7 @@ static int em25xx_bus_B_send_bytes(struct em28xx *dev, u16 addr, u8 *buf,
if (!ret) if (!ret)
return len; return len;
else if (ret > 0) else if (ret > 0)
return -ENODEV; return -ENXIO;
return ret; return ret;
/* /*
@ -356,7 +355,7 @@ static int em25xx_bus_B_recv_bytes(struct em28xx *dev, u16 addr, u8 *buf,
* bytes if we are on bus B AND there was no write attempt to the * bytes if we are on bus B AND there was no write attempt to the
* specified slave address before AND no device is present at the * specified slave address before AND no device is present at the
* requested slave address. * requested slave address.
* Anyway, the next check will fail with -ENODEV in this case, so avoid * Anyway, the next check will fail with -ENXIO in this case, so avoid
* spamming the system log on device probing and do nothing here. * spamming the system log on device probing and do nothing here.
*/ */
@ -369,7 +368,7 @@ static int em25xx_bus_B_recv_bytes(struct em28xx *dev, u16 addr, u8 *buf,
if (!ret) if (!ret)
return len; return len;
else if (ret > 0) else if (ret > 0)
return -ENODEV; return -ENXIO;
return ret; return ret;
/* /*
@ -410,7 +409,7 @@ static inline int i2c_check_for_device(struct em28xx_i2c_bus *i2c_bus, u16 addr)
rc = em2800_i2c_check_for_device(dev, addr); rc = em2800_i2c_check_for_device(dev, addr);
else if (i2c_bus->algo_type == EM28XX_I2C_ALGO_EM25XX_BUS_B) else if (i2c_bus->algo_type == EM28XX_I2C_ALGO_EM25XX_BUS_B)
rc = em25xx_bus_B_check_for_device(dev, addr); rc = em25xx_bus_B_check_for_device(dev, addr);
if (rc == -ENODEV) { if (rc == -ENXIO) {
if (i2c_debug) if (i2c_debug)
printk(" no device\n"); printk(" no device\n");
} }
@ -498,11 +497,15 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
(msgs[i].flags & I2C_M_RD) ? "read" : "write", (msgs[i].flags & I2C_M_RD) ? "read" : "write",
i == num - 1 ? "stop" : "nonstop", i == num - 1 ? "stop" : "nonstop",
addr, msgs[i].len); addr, msgs[i].len);
if (!msgs[i].len) { /* no len: check only for device presence */ if (!msgs[i].len) {
/*
* no len: check only for device presence
* This code is only called during device probe.
*/
rc = i2c_check_for_device(i2c_bus, addr); rc = i2c_check_for_device(i2c_bus, addr);
if (rc == -ENODEV) { if (rc == -ENXIO) {
rt_mutex_unlock(&dev->i2c_bus_lock); rt_mutex_unlock(&dev->i2c_bus_lock);
return rc; return -ENODEV;
} }
} else if (msgs[i].flags & I2C_M_RD) { } else if (msgs[i].flags & I2C_M_RD) {
/* read bytes */ /* read bytes */