From mboxrd@z Thu Jan  1 00:00:00 1970
From: daniel@caiaq.de (Daniel Mack)
Date: Wed, 2 Dec 2009 17:49:30 +0100
Subject: [PATCH 1/1] fix occasional ULPI timeouts with ehci-mxc
In-Reply-To: <1259770381-16987-1-git-send-email-valentin.longchamp@epfl.ch>
References: <1259770381-16987-1-git-send-email-valentin.longchamp@epfl.ch>
Message-ID: <20091202164930.GG14091@buzzloop.caiaq.de>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wed, Dec 02, 2009 at 05:13:01PM +0100, Valentin Longchamp wrote:
> On various mxc boards, the intial ULPI reads resulted in a timeout
> which prevented the transceiver to be identified and thus the ehci
> device to be probed.
> 
> Initializing the hardware lines connected to the transceiver (through
> pdata->init call) before actually enabling clocks and configuring
> registers in the devices fixes this problem.

Hmm, glad to hear it fixed your problem :) However, there is no real
ULPI communication done on the viewports before the board specific
init function is called, and the timeouts that are reported come from
the transceiver probing which is called at a later point.

Even with that patch applied, one board I have here fails to initialize
the OTG port.

> Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>

As it fixes a real world problem and doesn't seem to be harmful to
anyone else:

Acked-by: Daniel Mack <daniel@caiaq.de>

>  drivers/usb/host/ehci-mxc.c |   18 +++++++++---------
>  1 files changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-mxc.c b/drivers/usb/host/ehci-mxc.c
> index 35c56f4..689b683 100644
> --- a/drivers/usb/host/ehci-mxc.c
> +++ b/drivers/usb/host/ehci-mxc.c

[...]

> @@ -192,15 +201,6 @@ static int ehci_mxc_drv_probe(struct platform_device *pdev)
>  	if (ret < 0)
>  		goto err_init;
>  
> -	/* call platform specific init function */
> -	if (pdata->init) {
> -		ret = pdata->init(pdev);
> -		if (ret) {
> -			dev_err(dev, "platform init failed\n");
> -			goto err_init;
> -		}
> -	}
> -
>  	/* most platforms need some time to settle changed IO settings */
>  	mdelay(10);

You should probably also move the mdelay() and the comment then, right?
And as you're on it, the delay make more sense inside the
'if (pdata->init)' block ...

Thanks,
Daniel