On 2023-06-24 11:08:30, Krzysztof Kozlowski wrote: > On 24/06/2023 02:41, Marijn Suijten wrote: > > The downsteam driver for dispcc only ever gets and puts this clock > > without ever using it in the clocktree; this unnecessary workaround was > > never ported to mainline, hence the driver doesn't consume this clock > > and shouldn't be required by the bindings. > > > > Fixes: 8397c9c0c26b ("dt-bindings: clock: add QCOM SM6125 display clock bindings") > > Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> > > --- > > In perfect would we would like to know whether hardware needs this clock > enabled/controlled, not whether some driver needs it. I understand > though that with lack of proper docs we rely on drivers, so: It might only use this to figure out if those clocks have already probed or are available. The logic goes as follows: clk = devm_clk_get(&pdev->dev, "cfg_ahb_clk"); if (IS_ERR(clk)) { if (PTR_ERR(clk) != -EPROBE_DEFER) dev_err(&pdev->dev, "Unable to get ahb clock handle\n"); return PTR_ERR(clk); } devm_clk_put(&pdev->dev, clk); Nothing else uses/parents cfg_ahb_clk. Maybe with clk_ignore_unused or similar, it gets turned on but never off again? Indeed, a lack of documentation and comment from the manufacturer makes it impossible to know, and ignoring it (as the driver already does) works just fine. > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Thanks! - Marijn > > Best regards, > Krzysztof >