[PATCH] arm: smp-twd: check for uninitialized clock in twd_cpufreq_init

[Shilimkar, Santosh]

On Fri, Feb 17, 2012 at 4:04 PM, Tero Kristo <t-kristo at ti.com> wrote:
> Non-smp platforms don't have local timer support, but the twd_cpufreq_init
> only checks for IS_ERR during init. Check against null also, to avoid
> crashes during cpufreq transitions on non-smp platforms.
>
> Signed-off-by: Tero Kristo <t-kristo at ti.com>
> ---
I sent a patch for the same issue which Kevin reported.

Thread.
http://www.spinics.net/lists/arm-kernel/msg160275.html

>  arch/arm/kernel/smp_twd.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
> index 4285daa..dae8902 100644
> --- a/arch/arm/kernel/smp_twd.c
> +++ b/arch/arm/kernel/smp_twd.c
> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = {
>
>  static int twd_cpufreq_init(void)
>  {
> -       if (!IS_ERR(twd_clk))
> +       if (twd_clk && !IS_ERR(twd_clk))

Checking the clock node is not enoough because you can
not have clock node and rely on calibration..
Testing twd_evt is safe to avoid the issue.

Regards
santosh