diff options
author | Axel Lin <axel.lin@ingics.com> | 2015-05-23 15:16:48 +0800 |
---|---|---|
committer | Stefano Babic <sbabic@denx.de> | 2015-05-26 14:13:09 +0200 |
commit | 16b0c0ce83ec3f8bf96de69b1c84214cacc39416 (patch) | |
tree | d3277cb3ce0b5e5ee2ac3b9387b0088add824e23 /drivers/pwm | |
parent | 53940a50797d4287af1c998a251170ef65927533 (diff) |
pwm: imx: Prevent NULL pointer dereference
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>
Acked-by: Stefano Babic <sbabic@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>
Diffstat (limited to 'drivers/pwm')
-rw-r--r-- | drivers/pwm/pwm-imx.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index 40bf0275437..47799fc0d1f 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); } |