Hi Dmitry, On Wed, 2021-03-03 at 11:28 +0300, Dmitry Osipenko wrote: > 02.03.2021 14:21, Dmitry Osipenko пишет: > > The I2S reset may be asserted at a boot time. Tegra30 I2S driver doesn't > > manage the reset control and currently it happens to work because reset > > is implicitly deasserted by the Tegra AHUB driver, but the reset of I2C > > controller should be synchronous and I2S clock is disabled when AHUB is > > reset. Add reset control to the Tegra30 I2S driver. > > > > Note that I2S reset was always specified in Tegra30+ device-trees, hence > > DTB ABI changes aren't required. Also note that AHUB touches I2S resets, > > hence AHUB resets are now requested in a released state, allowing both > > drivers to control the I2S resets together. > > > > Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> > > --- > > sound/soc/tegra/tegra30_ahub.c | 14 ++++++++++--- > > sound/soc/tegra/tegra30_i2s.c | 36 +++++++++++++++++++++++++++++++++- > > sound/soc/tegra/tegra30_i2s.h | 1 + > > 3 files changed, 47 insertions(+), 4 deletions(-) > > ... > > @@ -579,7 +587,7 @@ static int tegra30_ahub_probe(struct platform_device *pdev) > > if (ret) > > return ret; > > > > - ahub->reset = devm_reset_control_array_get_exclusive(&pdev->dev); > > + ahub->reset = devm_reset_control_array_get_exclusive_released(&pdev->dev); > > Thinking a bit more about this, it looks like we actually want something > like: > > devm_reset_control_array_get_exclusive_released_named() > > that will request resets by given names and in a given order, similarly > to devm_clk_bulk_get(). This will be very handy for both Tegra audio and > GPU drivers. I'll prepare a v2 if there are no objections. I do have an untested reset control bulk API patch that I've just never finished, because I had no user. I'll send you an RFC, let me know if you can build on that. regards Philipp
