diff options
| author | Philipp Zabel <[email protected]> | 2024-07-03 10:50:10 +0200 |
|---|---|---|
| committer | Philipp Zabel <[email protected]> | 2024-07-03 10:50:10 +0200 |
| commit | 197c22b65ea6a70eb377760282e7a634c3a812ab (patch) | |
| tree | 37f34004b49e2081abb9eb4751e4b3d5c8a34e42 /drivers/pwm/pwm-stm32.c | |
| parent | fd88137bfbb83bee678abef840dcafa13262f5ca (diff) | |
| parent | 1cb7d29157603561af4c38535e936850ceb99f0f (diff) | |
Merge tag 'regulator-hw-enable-helper' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into reset/next
regulator: Add helper to allow enable/disable in interrupt context
Add a helper function that enables exclusive consumers to bypass locking
and do an enable/disable from within interrupt context.
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>
Diffstat (limited to 'drivers/pwm/pwm-stm32.c')
| -rw-r--r-- | drivers/pwm/pwm-stm32.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c index a2f231d13a9f..8bae3fd2b330 100644 --- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -321,22 +321,30 @@ static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch, * First we need to find the minimal value for prescaler such that * * period_ns * clkrate - * ------------------------------ + * ------------------------------ < max_arr + 1 * NSEC_PER_SEC * (prescaler + 1) * - * isn't bigger than max_arr. + * This equation is equivalent to + * + * period_ns * clkrate + * ---------------------------- < prescaler + 1 + * NSEC_PER_SEC * (max_arr + 1) + * + * Using integer division and knowing that the right hand side is + * integer, this is further equivalent to + * + * (period_ns * clkrate) // (NSEC_PER_SEC * (max_arr + 1)) ≤ prescaler */ prescaler = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), - (u64)NSEC_PER_SEC * priv->max_arr); - if (prescaler > 0) - prescaler -= 1; - + (u64)NSEC_PER_SEC * ((u64)priv->max_arr + 1)); if (prescaler > MAX_TIM_PSC) return -EINVAL; prd = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), (u64)NSEC_PER_SEC * (prescaler + 1)); + if (!prd) + return -EINVAL; /* * All channels share the same prescaler and counter so when two @@ -673,7 +681,8 @@ static int stm32_pwm_probe(struct platform_device *pdev) * .apply() won't overflow. */ if (clk_get_rate(priv->clk) > 1000000000) - return dev_err_probe(dev, -EINVAL, "Failed to lock clock\n"); + return dev_err_probe(dev, -EINVAL, "Clock freq too high (%lu)\n", + clk_get_rate(priv->clk)); chip->ops = &stm32pwm_ops; |