pwm: Expose PWM_WFHWSIZE in public header

The WFHWSIZE constant defines the maximum size for the hardware-specific
waveform representation buffer. It is currently local to
drivers/pwm/core.c, which makes it inaccessible to external tools like
bindgen.

Move the constant to include/linux/pwm.h to make it part of the public
API. As part of this change, rename it to PWM_WFHWSIZE to follow
standard kernel conventions for namespacing macros in public headers.

This allows bindgen to automatically generate a corresponding constant
for the Rust PWM abstractions, ensuring the value remains synchronized
between the C core and Rust code and preventing future maintenance
issues.

Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://lore.kernel.org/r/20250702-rust-next-pwm-working-fan-for-sending-v7-1-67ef39ff1d29@samsung.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 50aa0528a2653b69efb632d5f3b9b78c0b957909..0d66376a83ec350e0c3718959f4d794efd71595a 100644 (file)
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -210,8 +210,6 @@ static int __pwm_write_waveform(struct pwm_chip *chip, struct pwm_device *pwm, c
        return ret;
 }
 
-#define WFHWSIZE 20
-
 /**
  * pwm_round_waveform_might_sleep - Query hardware capabilities
  * Cannot be used in atomic context.
@@ -248,10 +246,10 @@ int pwm_round_waveform_might_sleep(struct pwm_device *pwm, struct pwm_waveform *
        struct pwm_chip *chip = pwm->chip;
        const struct pwm_ops *ops = chip->ops;
        struct pwm_waveform wf_req = *wf;
-       char wfhw[WFHWSIZE];
+       char wfhw[PWM_WFHWSIZE];
        int ret_tohw, ret_fromhw;
 
-       BUG_ON(WFHWSIZE < ops->sizeof_wfhw);
+       BUG_ON(PWM_WFHWSIZE < ops->sizeof_wfhw);
 
        if (!pwmchip_supports_waveform(chip))
                return -EOPNOTSUPP;
@@ -306,10 +304,10 @@ int pwm_get_waveform_might_sleep(struct pwm_device *pwm, struct pwm_waveform *wf
 {
        struct pwm_chip *chip = pwm->chip;
        const struct pwm_ops *ops = chip->ops;
-       char wfhw[WFHWSIZE];
+       char wfhw[PWM_WFHWSIZE];
        int err;
 
-       BUG_ON(WFHWSIZE < ops->sizeof_wfhw);
+       BUG_ON(PWM_WFHWSIZE < ops->sizeof_wfhw);
 
        if (!pwmchip_supports_waveform(chip) || !ops->read_waveform)
                return -EOPNOTSUPP;
@@ -334,11 +332,11 @@ static int __pwm_set_waveform(struct pwm_device *pwm,
 {
        struct pwm_chip *chip = pwm->chip;
        const struct pwm_ops *ops = chip->ops;
-       char wfhw[WFHWSIZE];
+       char wfhw[PWM_WFHWSIZE];
        struct pwm_waveform wf_rounded;
        int err, ret_tohw;
 
-       BUG_ON(WFHWSIZE < ops->sizeof_wfhw);
+       BUG_ON(PWM_WFHWSIZE < ops->sizeof_wfhw);
 
        if (!pwmchip_supports_waveform(chip))
                return -EOPNOTSUPP;
@@ -650,9 +648,9 @@ static int __pwm_apply(struct pwm_device *pwm, const struct pwm_state *state)
 
        if (pwmchip_supports_waveform(chip)) {
                struct pwm_waveform wf;
-               char wfhw[WFHWSIZE];
+               char wfhw[PWM_WFHWSIZE];
 
-               BUG_ON(WFHWSIZE < ops->sizeof_wfhw);
+               BUG_ON(PWM_WFHWSIZE < ops->sizeof_wfhw);
 
                pwm_state2wf(state, &wf);
 
@@ -809,10 +807,10 @@ int pwm_get_state_hw(struct pwm_device *pwm, struct pwm_state *state)
                return -ENODEV;
 
        if (pwmchip_supports_waveform(chip) && ops->read_waveform) {
-               char wfhw[WFHWSIZE];
+               char wfhw[PWM_WFHWSIZE];
                struct pwm_waveform wf;
 
-               BUG_ON(WFHWSIZE < ops->sizeof_wfhw);
+               BUG_ON(PWM_WFHWSIZE < ops->sizeof_wfhw);
 
                ret = __pwm_read_waveform(chip, pwm, &wfhw);
                if (ret)
@@ -1696,8 +1694,8 @@ static bool pwm_ops_check(const struct pwm_chip *chip)
                    !ops->write_waveform)
                        return false;
 
-               if (WFHWSIZE < ops->sizeof_wfhw) {
-                       dev_warn(pwmchip_parent(chip), "WFHWSIZE < %zu\n", ops->sizeof_wfhw);
+               if (PWM_WFHWSIZE < ops->sizeof_wfhw) {
+                       dev_warn(pwmchip_parent(chip), "PWM_WFHWSIZE < %zu\n", ops->sizeof_wfhw);
                        return false;
                }
        } else {

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 2492c91452f9641881e9923e5a97e0705047da59..8cafc483db53addf95591d1ac74287532c0fa0ee 100644 (file)
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -274,6 +274,8 @@ struct pwm_capture {
        unsigned int duty_cycle;
 };
 
+#define PWM_WFHWSIZE 20
+
 /**
  * struct pwm_ops - PWM controller operations
  * @request: optional hook for requesting a PWM