[U-Boot] [PATCH 1/2] pwm: imx: Prevent NULL pointer dereference

[Heiko Schocher <hs@denx.de>]

Hello Axel,

Am 23.05.2015 09:16, schrieb Axel Lin:
> pwm_id_to_reg() can return NULL, so add NULL testing to prevent NULL pointer
> dereference.
>
> Signed-off-by: Axel Lin <axel.lin@ingics.com>
> ---
>   drivers/pwm/pwm-imx.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)

Acked-by: Heiko Schocher <hs@denx.de>

bye,
Heiko
>
> diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
> index 40bf027..47799fc 100644
> --- a/drivers/pwm/pwm-imx.c
> +++ b/drivers/pwm/pwm-imx.c
> @@ -18,6 +18,9 @@ int pwm_init(int pwm_id, int div, int invert)
>   {
>   	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> +	if (!pwm)
> +		return -1;
> +
>   	writel(0, &pwm->ir);
>   	return 0;
>   }
> @@ -28,6 +31,9 @@ int pwm_config(int pwm_id, int duty_ns, int period_ns)
>   	unsigned long period_cycles, duty_cycles, prescale;
>   	u32 cr;
>
> +	if (!pwm)
> +		return -1;
> +
>   	pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
>   			  &prescale);
>
> @@ -47,6 +53,9 @@ int pwm_enable(int pwm_id)
>   {
>   	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> +	if (!pwm)
> +		return -1;
> +
>   	setbits_le32(&pwm->cr, PWMCR_EN);
>   	return 0;
>   }
> @@ -55,5 +64,8 @@ void pwm_disable(int pwm_id)
>   {
>   	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> +	if (!pwm)
> +		return;
> +
>   	clrbits_le32(&pwm->cr, PWMCR_EN);
>   }
>

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