Hi,

On Thu, Oct 25, 2012 at 12:33:18PM +0200, Michael Trimarchi wrote:

quoted

quoted

quoted

@@ -587,9 +587,9 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 		goto err_i2c_init;
 	}
 
-	/* We have an error */
-	if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
-			    OMAP_I2C_STAT_XUDF)) {
+	if ((dev->cmd_err & OMAP_I2C_STAT_AL)
+			|| (dev->cmd_err & OMAP_I2C_STAT_ROVR)
+			|| (dev->cmd_err & OMAP_I2C_STAT_XUDF)) {

Sorry, what is the difference? I didn't understand the optimisation
and why now is more clear. Can you just add a comment?

semantically they're not the same, right ? We want to check if each of
those bits are set, not if all of them are set together.

my 2 cents.

You are doing the same thing, but of course is better with just one

I never claimed the contrary. I said *semantically* they're not the
same.

*if* as before . A general rule is: when you have logic expression you

We still have a single *if* and I'm sure compiler will optimize that
expression as much as it likes.

can use undefined states to simplify the logic. 

don't-care is not the same as undefined states.

-- 
balbi
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