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SubjectRe: [PATCH v6 10/10] pwm: dwc: use clock rate in hz to avoid rounding issues
Hello Ben,

On Thu, Oct 20, 2022 at 04:16:10PM +0100, Ben Dooks wrote:
> As noted, the clock-rate when not a nice multiple of ns is probably
> going to end up with inacurate caculations, as well as on a non pci
> system the rate may change (although we've not put a clock rate
> change notifier in this code yet) so we also add some quick checks
> of the rate when we do any calculations with it.
>
> Signed-off-by; Ben Dooks <ben.dooks@sifive.com>
> Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
> drivers/pwm/pwm-dwc-of.c | 2 +-
> drivers/pwm/pwm-dwc.c | 29 ++++++++++++++++++++---------
> drivers/pwm/pwm-dwc.h | 2 +-
> 3 files changed, 22 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/pwm/pwm-dwc-of.c b/drivers/pwm/pwm-dwc-of.c
> index c5b4351cc7b0..5f7f066859d4 100644
> --- a/drivers/pwm/pwm-dwc-of.c
> +++ b/drivers/pwm/pwm-dwc-of.c
> @@ -50,7 +50,7 @@ static int dwc_pwm_plat_probe(struct platform_device *pdev)
> return dev_err_probe(dev, PTR_ERR(dwc->clk),
> "failed to get timer clock\n");
>
> - dwc->clk_ns = NSEC_PER_SEC / clk_get_rate(dwc->clk);
> + dwc->clk_rate = clk_get_rate(dwc->clk);

Given that clk_ns is introduced only in this series, I suggest to make
it right from the start.

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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