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| author | Thomas Gleixner <tglx@linutronix.de> | 2024-07-13 12:07:10 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-07-13 12:07:10 +0200 |
| commit | b7625d67eb1a63d33b0a2a4518ce4897d27f7465 (patch) | |
| tree | 372459935f602bac331ad0185f2dc5cc23d76924 /drivers/pwm/pwm-stm32.c | |
| parent | f7d43dd206e7e18c182f200e67a8db8c209907fa (diff) | |
| parent | 4bdc3eaa102b6bedb0800f76f53eca516d5cf20c (diff) | |
| download | lwn-b7625d67eb1a63d33b0a2a4518ce4897d27f7465.tar.gz lwn-b7625d67eb1a63d33b0a2a4518ce4897d27f7465.zip | |
Merge tag 'timers-v6.11-rc1' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core
Pull clocksource/event driver updates from Daniel Lezcano:
- Remove unnecessary local variables initialization as they will be
initialized in the code path anyway right after on the ARM arch
timer and the ARM global timer (Li kunyu)
- Fix a race condition in the interrupt leading to a deadlock on the
SH CMT driver. Note that this fix was not tested on the platform
using this timer but the fix seems reasonable enough to be picked
confidently (Niklas Söderlund)
- Increase the rating of the gic-timer and use the configured width
clocksource register on the MIPS architecture (Jiaxun Yang)
- Add the DT bindings for the TMU on the Renesas platforms (Geert
Uytterhoeven)
- Add the DT bindings for the SOPHGO SG2002 clint on RiscV (Thomas
Bonnefille)
- Add the rtl-otto timer driver along with the DT bindings for the
Realtek platform (Chris Packham)
Link: https://lore.kernel.org/all/91cd05de-4c5d-4242-a381-3b8a4fe6a2a2@linaro.org
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; |