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authorVladimir Zapolskiy <vz@mleia.com>2023-07-17 17:52:57 +0200
committerThierry Reding <thierry.reding@gmail.com>2023-08-22 10:14:16 +0200
commit4aae44f65827f0213a7361cf9c32cfe06114473f (patch)
tree921be0afdcb7539eae249e680c3a2333ca7d899d /drivers/pwm
parentpwm: atmel: Simplify using devm functions (diff)
downloadlinux-4aae44f65827f0213a7361cf9c32cfe06114473f.tar.xz
linux-4aae44f65827f0213a7361cf9c32cfe06114473f.zip
pwm: lpc32xx: Remove handling of PWM channels
Because LPC32xx PWM controllers have only a single output which is registered as the only PWM device/channel per controller, it is known in advance that pwm->hwpwm value is always 0. On basis of this fact simplify the code by removing operations with pwm->hwpwm, there is no controls which require channel number as input. Even though I wasn't aware at the time when I forward ported that patch, this fixes a null pointer dereference as lpc32xx->chip.pwms is NULL before devm_pwmchip_add() is called. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Fixes: 3d2813fb17e5 ("pwm: lpc32xx: Don't modify HW state in .probe() after the PWM chip was registered") Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-lpc32xx.c16
1 files changed, 8 insertions, 8 deletions
diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c
index 86a0ea0f6955..806f0bb3ad6d 100644
--- a/drivers/pwm/pwm-lpc32xx.c
+++ b/drivers/pwm/pwm-lpc32xx.c
@@ -51,10 +51,10 @@ static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
if (duty_cycles > 255)
duty_cycles = 255;
- val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+ val = readl(lpc32xx->base);
val &= ~0xFFFF;
val |= (period_cycles << 8) | duty_cycles;
- writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+ writel(val, lpc32xx->base);
return 0;
}
@@ -69,9 +69,9 @@ static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
if (ret)
return ret;
- val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+ val = readl(lpc32xx->base);
val |= PWM_ENABLE;
- writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+ writel(val, lpc32xx->base);
return 0;
}
@@ -81,9 +81,9 @@ static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
u32 val;
- val = readl(lpc32xx->base + (pwm->hwpwm << 2));
+ val = readl(lpc32xx->base);
val &= ~PWM_ENABLE;
- writel(val, lpc32xx->base + (pwm->hwpwm << 2));
+ writel(val, lpc32xx->base);
clk_disable_unprepare(lpc32xx->clk);
}
@@ -141,9 +141,9 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
lpc32xx->chip.npwm = 1;
/* If PWM is disabled, configure the output to the default value */
- val = readl(lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
+ val = readl(lpc32xx->base);
val &= ~PWM_PIN_LEVEL;
- writel(val, lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
+ writel(val, lpc32xx->base);
ret = devm_pwmchip_add(&pdev->dev, &lpc32xx->chip);
if (ret < 0) {