Booting a mx51babbage board with a non-dt kernel leads to the following crash:
Unable to handle kernel NULL pointer dereference at virtual address 0000001c pgd = 80004000 [0000001c] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.11.0-next-20130903 #287 task: 9f860000 ti: 9f862000 task.ti: 9f862000 PC is at of_get_next_available_child+0x5c/0x68 LR is at of_get_next_available_child+0x1c/0x68 pc : [<8043ea58>] lr : [<8043ea18>] psr: 60000193 sp : 9f863d58 ip : 00000000 fp : 9f863d74 r10: 9f89a010 r9 : 9f862000 r8 : 807bb26c r7 : 80615d5c r6 : 00000000 r5 : 60000113 r4 : 00000000 r3 : 00000000 r2 : 808770a4 r1 : 00000011 r0 : 60000113 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 90004019 DAC: 00000017 Process swapper/0 (pid: 1, stack limit = 0x9f862240) Stack: (0x9f863d58 to 0x9f864000)
In order to fix it, return an error when 'of_id' is NULL, which happens for the non-dt case.
Also checked that audio is still functional when running the dt kernel for this board after applying this patch.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com --- sound/soc/fsl/imx-audmux.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/sound/soc/fsl/imx-audmux.c b/sound/soc/fsl/imx-audmux.c index ab17381..2b29b48 100644 --- a/sound/soc/fsl/imx-audmux.c +++ b/sound/soc/fsl/imx-audmux.c @@ -317,6 +317,9 @@ static int imx_audmux_probe(struct platform_device *pdev) const struct of_device_id *of_id = of_match_device(imx_audmux_dt_ids, &pdev->dev);
+ if (!of_id) + return -EINVAL; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); audmux_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(audmux_base))