Messages in this thread | | | Subject | Re: [RFC PATCH v4 04/14] i2c: tegra: Fix runtime resume to re-init VI I2C | From | Sowjanya Komatineni <> | Date | Mon, 27 Jul 2020 13:58:37 -0700 |
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On 7/26/20 4:53 PM, Dmitry Osipenko wrote: > 24.07.2020 02:51, Sowjanya Komatineni пишет: >> VI I2C is on host1x bus and is part of VE power domain. >> >> During suspend/resume VE power domain goes through power off/on. >> >> So, controller reset followed by i2c re-initialization is required >> after the domain power up. >> >> This patch fixes it. >> >> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> >> --- >> drivers/i2c/busses/i2c-tegra.c | 16 ++++++++++++++++ >> 1 file changed, 16 insertions(+) >> >> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c >> index 7b93c45..1bf3666 100644 >> --- a/drivers/i2c/busses/i2c-tegra.c >> +++ b/drivers/i2c/busses/i2c-tegra.c >> @@ -293,6 +293,8 @@ struct tegra_i2c_dev { >> bool is_curr_atomic_xfer; >> }; >> >> +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit); >> + >> static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, >> unsigned long reg) >> { >> @@ -675,8 +677,22 @@ static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev) >> goto disable_slow_clk; >> } >> >> + /* >> + * VI I2C device is attached to VE power domain which goes through >> + * power ON/OFF during PM runtime resume/suspend. So, controller >> + * should go through reset and need to re-initialize after power >> + * domain ON. >> + */ >> + if (i2c_dev->is_vi) { >> + ret = tegra_i2c_init(i2c_dev, true); >> + if (ret) >> + goto disable_div_clk; >> + } >> + >> return 0; >> >> +disable_div_clk: >> + clk_disable(i2c_dev->div_clk); >> disable_slow_clk: >> clk_disable(i2c_dev->slow_clk); >> disable_fast_clk: >> > This look okay, but isn't RPM usage a bit too expensive for VI? Maybe > RPM autodelay needs to be set for the I2C driver? > > Reviewed-by: Dmitry Osipenko <digetx@gmail.com> > Thanks Dmitry. Will look into and have separate patch for VI I2C RPM auto-delay out of this series sometime next week.
Regards
Sowjanya
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