[PATCH 1/2] ARM: OMAP2+: Prevent potential crash if GPMC probe fails

Ezequiel Garcia ezequiel.garcia at free-electrons.com
Sat Feb 9 10:55:49 EST 2013


On Fri, Feb 08, 2013 at 04:56:19PM -0600, Jon Hunter wrote:
> 
> On 02/01/2013 04:08 PM, Tony Lindgren wrote:
> > * Jon Hunter <jon-hunter at ti.com> [130201 08:42]:
> >> If the GPMC probe fails, devices that use the GPMC (such as ethernet
> >> chips, flash memories, etc) can still allocate a GPMC chip-select and
> >> register the device. On the OMAP2420 H4 board, this was causing the
> >> kernel to crash after the gpmc probe failed and the board attempted
> >> to start networking. Prevent this by marking all the chip-selects as
> >> reserved by default and only make them available for devices to request
> >> if the GPMC probe succeeds.
> > 
> > Thanks applying into omap-for-v3.9/gpmc.
> 
> Hi Tony, this one appears to be merged incorrectly. The unreserve ended 
> up in the gpmc_calc_timings() function. Here is a patch to fix.
> 
> Cheers
> Jon
> 
> From ebc0613fb5a70f36fcb119cbe58724f9b442903a Mon Sep 17 00:00:00 2001
> From: Jon Hunter <jon-hunter at ti.com>
> Date: Fri, 8 Feb 2013 16:48:25 -0600
> Subject: [PATCH] ARM: OMAP2+: Fix-up gpmc merge error
> 
> Commit "ARM: OMAP2+: Prevent potential crash if GPMC probe fails" added
> code to ensure that GPMC chip-selects could not be requested until the
> device probe was successful. The chip-selects should have been
> unreserved at the end of the probe function, but the code to unreserve
> them appears to have ended up in the gpmc_calc_timings() function and
> hence, this is causing problems requesting chip-selects. Fix this merge
> error by unreserving the chip-selects at the end of the probe, but
> before we call the gpmc child probe functions (for device-tree) which
> request a chip-select.
> 
> Signed-off-by: Jon Hunter <jon-hunter at ti.com>

Without this patch, GPMC is currently broken on my igep board setup,
if initialized through a device tree.

Tested-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>

Thanks a lot for the fix,

-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com



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