Re: [PATCH 2/2] clk: scmi: Fix min and max rate when registering clocks with discrete rates

From: Sudeep Holla
Date: Wed Jul 08 2020 - 16:24:18 EST


On Wed, Jul 08, 2020 at 12:07:25PM +0100, Sudeep Holla wrote:
> Currently we are not initializing the scmi clock with discrete rates
> correctly. We fetch the min_rate and max_rate value only for clocks with
> ranges and ignore the ones with discrete rates. This will lead to wrong
> initialization of rate range when clock supports discrete rate.
>
> Fix this by using the first and the last rate in the sorted list of the
> discrete clock rates while registering the clock.
>
> Fixes: 6d6a1d82eaef7 ("clk: add support for clocks provided by SCMI")
> Reported-by: Dien Pham <dien.pham.ry@xxxxxxxxxxx>
> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
> drivers/clk/clk-scmi.c | 22 +++++++++++++++++++---
> 1 file changed, 19 insertions(+), 3 deletions(-)
>
> Hi Stephen,
>
> If you fine, I can take this via ARM SoC along with the change in firmware
> driver. But it is fine if you want to merge this independently as it should
> be fine. Let me know either way.
>
> Regards,
> Sudeep
>
> diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
> index c491f5de0f3f..ea65b7bf1408 100644
> --- a/drivers/clk/clk-scmi.c
> +++ b/drivers/clk/clk-scmi.c
> @@ -103,6 +103,8 @@ static const struct clk_ops scmi_clk_ops = {
> static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk)
> {
> int ret;
> + unsigned long min_rate, max_rate;
> +
> struct clk_init_data init = {
> .flags = CLK_GET_RATE_NOCACHE,
> .num_parents = 0,
> @@ -112,9 +114,23 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk)
>
> sclk->hw.init = &init;
> ret = devm_clk_hw_register(dev, &sclk->hw);
> - if (!ret)
> - clk_hw_set_rate_range(&sclk->hw, sclk->info->range.min_rate,
> - sclk->info->range.max_rate);
> + if (ret)
> + return ret;
> +
> + if (sclk->info->rate_discrete) {
> + int num_rates = sclk->info->list.num_rates;
> +
> + if (num_rates <= 0)
> + return -EINVAL;
> +
> + min_rate = sclk->info->list.rates[0]

I seem to have sent a version with ; missing above though I fixed but
sent the old stale version as I had written a note to you ð

--
Regards,
Sudeep