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(+)
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); }