pwm: bcm2835: Fix period_ns range check (7e9713af) · Commits · 戴 / test

drivers/pwm/pwm-bcm2835.c

+5 −4

Original line number	Diff line number	Diff line
		@@ -21,7 +21,7 @@
		#define PERIOD(x) (((x) * 0x10) + 0x10)
		#define DUTY(x) (((x) * 0x10) + 0x14)

		#define MIN_PERIOD 108 /* 9.2 MHz max. PWM clock */
		#define PERIOD_MIN 0x2

		struct bcm2835_pwm {
		struct pwm_chip chip;
		@@ -64,6 +64,7 @@ static int bcm2835_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
		struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
		unsigned long rate = clk_get_rate(pc->clk);
		unsigned long scaler;
		u32 period;

		if (!rate) {
		dev_err(pc->dev, "failed to get clock rate\n");
		@@ -71,14 +72,14 @@ static int bcm2835_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
		}

		scaler = DIV_ROUND_CLOSEST(NSEC_PER_SEC, rate);
		period = DIV_ROUND_CLOSEST(period_ns, scaler);

		if (period_ns <= MIN_PERIOD)
		if (period < PERIOD_MIN)
		return -EINVAL;

		writel(DIV_ROUND_CLOSEST(duty_ns, scaler),
		pc->base + DUTY(pwm->hwpwm));
		writel(DIV_ROUND_CLOSEST(period_ns, scaler),
		pc->base + PERIOD(pwm->hwpwm));
		writel(period, pc->base + PERIOD(pwm->hwpwm));

		return 0;
		}