From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joonyoung Shim <jy0922.shim@samsung.com>
Subject: Re: [PATCH v2] input: qt602240 - Add ATMEL QT602240 touchscreen	driver
Date: Tue, 29 Jun 2010 12:33:35 +0900
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To: Dan Murphy <murpdj72@gmail.com>
Cc: Joonyoung Shim <dofmind@gmail.com>, Henrik Rydberg <rydberg@euromail.se>, dmitry.torokhov@gmail.com, linux-input@vger.kernel.org, kyungmin.park@samsung.com

Hi,

On 6/28/2010 11:26 PM, Dan Murphy wrote:
> I don't see any error handling from the IC here.
> 
> Generally this IC should give a few error messages if a X/Y line is broken,
> the chip goes into reset, or the chip is missed configured.
> 

The configuration error can occur and if the chip detect it, we get
messages from message object in interrupt handler and can see it. If 
needs, i can add error print.

> This is a bad situation here
> +       /* Read dummy message to make high CHG pin */
> +       do {
> +               ret = qt602240_read_object(data, QT602240_GEN_MESSAGE, 0);
> +               if (ret < 0)
> +                       return ret;
> +       } while (ret != 0xff);
> 
> The chip may have an error and constantly send you the message which means
> you will never get out of this loop.  This can be bad as your probe or
> load_fw may never return.
> 

Hmm, this chip reports always 0xff value if the message is nothing, but
i will add count to prevent unlikely loop.

Thanks.