Re: [PATCH] added S6E63M0 AMOLED LCD Panel driver.

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 31 Mar 2010 11:41:54 +0900 InKi Dae <daeinki@gmail.com> wrote:

> Hi Andrew,
> 
> all the calls to s6e63m0_panel_send_sequence() would return -EINVAL.
> by api_async() of driver/spi/spi.c

No, spi_async() does

	master->transfer(spi, message);

which can return at least EIO, EINPROGRESS, EINVAL or ETIMEDOUT.

> so I think that those return values aren't changed to other.
> 
> and final step is to check only whether the return value is 0 or not.
> if you still think that this code has minor problem or you want it to
> be corrected
> then I will patch this code to be corrected anytime.

It's a bug.

Also s6e63m0_power_on() is sloppy.  It again or's together disparate
errnos.  Then if _anything_ failed it returns hardwired -EIO, but it
should instead propagate the callee's errno back up to the caller.

And s6e63m0_power_on() can return -EFAULT in several places, which is
nonsensical.

None of this is very critical, just ... sloppy.