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

[Jon Hunter <jon-hunter@ti.com>]

On 02/01/2013 04:08 PM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@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@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@ti.com>
---
 arch/arm/mach-omap2/gpmc.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index 1adb2d4..1e8bcb4 100644
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -1125,9 +1125,6 @@ int gpmc_calc_timings(struct gpmc_timings *gpmc_t,
 	/* TODO: remove, see function definition */
 	gpmc_convert_ps_to_ns(gpmc_t);
 
-	/* Now the GPMC is initialised, unreserve the chip-selects */
-	gpmc_cs_map = 0;
-
 	return 0;
 }
 
@@ -1388,6 +1385,9 @@ static int gpmc_probe(struct platform_device *pdev)
 	if (IS_ERR_VALUE(gpmc_setup_irq()))
 		dev_warn(gpmc_dev, "gpmc_setup_irq failed\n");
 
+	/* Now the GPMC is initialised, unreserve the chip-selects */
+	gpmc_cs_map = 0;
+
 	rc = gpmc_probe_dt(pdev);
 	if (rc < 0) {
 		clk_disable_unprepare(gpmc_l3_clk);
-- 
1.7.10.4