diff mbox

[2/6] i2c: sh_mobile: improve error handling

Message ID 1398896470-24663-3-git-send-email-wsa@the-dreams.de
State Superseded
Headers show

Commit Message

Wolfram Sang April 30, 2014, 10:21 p.m. UTC 
From: Wolfram Sang <wsa+renesas@sang-engineering.com>

Use standard i2c error codes for i2c failures. Also, don't print
something on timeout since it happens regularly with i2c. Simplify some,
logic, too.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/i2c/busses/i2c-sh_mobile.c | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

Comments

Geert Uytterhoeven April 30, 2014, 10:25 p.m. UTC | #1 
Hi Wolfram,

On Thu, May 1, 2014 at 12:21 AM, Wolfram Sang <wsa@the-dreams.de> wrote:
> Use standard i2c error codes for i2c failures. Also, don't print
> something on timeout since it happens regularly with i2c. Simplify some,
> logic, too.

You may want to keep the timeout messages with dev_dbg()?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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Wolfram Sang May 2, 2014, 7:19 a.m. UTC | #2 
On Thu, May 01, 2014 at 12:25:38AM +0200, Geert Uytterhoeven wrote:
> Hi Wolfram,
> 
> On Thu, May 1, 2014 at 12:21 AM, Wolfram Sang <wsa@the-dreams.de> wrote:
> > Use standard i2c error codes for i2c failures. Also, don't print
> > something on timeout since it happens regularly with i2c. Simplify some,
> > logic, too.
> 
> You may want to keep the timeout messages with dev_dbg()?

Not really. We now have an I2C tracer which shows the return value of
the transfer. I really want to reduce debug output of all drivers in
favor of the tracer.
diff mbox

Patch

diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index d91625eea6bb..d2fa222df3d1 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -480,7 +480,7 @@  static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg,
 {
 	if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) {
 		dev_err(pd->dev, "Unsupported zero length i2c read\n");
-		return -EIO;
+		return -EOPNOTSUPP;
 	}
 
 	if (do_init) {
@@ -515,17 +515,12 @@  static int poll_dte(struct sh_mobile_i2c_data *pd)
 			break;
 
 		if (val & ICSR_TACK)
-			return -EIO;
+			return -ENXIO;
 
 		udelay(10);
 	}
 
-	if (!i) {
-		dev_warn(pd->dev, "Timeout polling for DTE!\n");
-		return -ETIMEDOUT;
-	}
-
-	return 0;
+	return i ? 0 : -ETIMEDOUT;
 }
 
 static int poll_busy(struct sh_mobile_i2c_data *pd)
@@ -543,20 +538,18 @@  static int poll_busy(struct sh_mobile_i2c_data *pd)
 		 */
 		if (!(val & ICSR_BUSY)) {
 			/* handle missing acknowledge and arbitration lost */
-			if ((val | pd->sr) & (ICSR_TACK | ICSR_AL))
-				return -EIO;
+			val |= pd->sr;
+			if (val & ICSR_TACK)
+				return -ENXIO;
+			if (val & ICSR_AL)
+				return -EAGAIN;
 			break;
 		}
 
 		udelay(10);
 	}
 
-	if (!i) {
-		dev_err(pd->dev, "Polling timed out\n");
-		return -ETIMEDOUT;
-	}
-
-	return 0;
+	return i ? 0 : -ETIMEDOUT;
 }
 
 static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,