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SubjectRe: [PATCH V2 1/4] clk: imx: pll14xx: avoid glitch when set rate
Date
Quoting Peng Fan (2019-08-26 02:42:14)
> From: Peng Fan <peng.fan@nxp.com>
>
> According to PLL1443XA and PLL1416X spec,
> "When BYPASS is 0 and RESETB is changed from 0 to 1, FOUT starts to
> output unstable clock until lock time passes. PLL1416X/PLL1443XA may
> generate a glitch at FOUT."
>
> So set BYPASS when RESETB is changed from 0 to 1 to avoid glitch.
> In the end of set rate, BYPASS will be cleared.
>
> When prepare clock, also need to take care to avoid glitch. So
> we also follow Spec to set BYPASS before RESETB changed from 0 to 1.
> And add a check if the RESETB is already 0, directly return 0;
>
> Fixes: 8646d4dcc7fb ("clk: imx: Add PLLs driver for imx8mm soc")
> Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---

Please make cover letters for multi-patch series.

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