From: Michal Wilczynski Date: Thu, 16 Oct 2025 13:38:01 +0000 (+0200) Subject: pwm: Export `pwmchip_release` for external use X-Git-Tag: v6.19-rc1~154^2~2^2~10 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ce284f882022ebcb953984c7eccf4fc4eb531978;p=thirdparty%2Fkernel%2Flinux.git pwm: Export `pwmchip_release` for external use The upcoming Rust abstraction layer for the PWM subsystem uses a custom `dev->release` handler to safely manage the lifetime of its driver data. To prevent leaking the memory of the `struct pwm_chip` (allocated by `pwmchip_alloc`), this custom handler must also call the original `pwmchip_release` function to complete the cleanup. Make `pwmchip_release` a global, exported function so that it can be called from the Rust FFI bridge. This involves removing the `static` keyword, adding a prototype to the public header, and exporting the symbol. Reviewed-by: Elle Rhumsaa Signed-off-by: Michal Wilczynski Link: https://patch.msgid.link/20251016-rust-next-pwm-working-fan-for-sending-v16-1-a5df2405d2bd@samsung.com Signed-off-by: Uwe Kleine-König --- diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index ea2ccf42e8144..47c9333baaf6c 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -1608,12 +1608,13 @@ void pwmchip_put(struct pwm_chip *chip) } EXPORT_SYMBOL_GPL(pwmchip_put); -static void pwmchip_release(struct device *pwmchip_dev) +void pwmchip_release(struct device *pwmchip_dev) { struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev); kfree(chip); } +EXPORT_SYMBOL_GPL(pwmchip_release); struct pwm_chip *pwmchip_alloc(struct device *parent, unsigned int npwm, size_t sizeof_priv) { diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 549ac4aaad59b..148f056f336bb 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -488,6 +488,12 @@ int __pwmchip_add(struct pwm_chip *chip, struct module *owner); #define pwmchip_add(chip) __pwmchip_add(chip, THIS_MODULE) void pwmchip_remove(struct pwm_chip *chip); +/* + * For FFI wrapper use only: + * The Rust PWM abstraction needs this to properly free the pwm_chip. + */ +void pwmchip_release(struct device *dev); + int __devm_pwmchip_add(struct device *dev, struct pwm_chip *chip, struct module *owner); #define devm_pwmchip_add(dev, chip) __devm_pwmchip_add(dev, chip, THIS_MODULE)