Re: [PATCH v6 3/3] drm/xe/i2c: Keep the i2c controller always enabled
Raag Jadav <[email protected]>
| Newsgroups | org.freedesktop.lists.intel-xe,org.kernel.vger.linux-kernel,org.kernel.vger.stable |
|---|---|
| Message-ID | <[email protected]> |
On Wed, Jul 22, 2026 at 03:35:54PM +0200, Heikki Krogerus wrote:
> Some platforms make an assumption that the i2c controller's
> enabled state indicates also the power state of the
> controller. This can create a problem when the controller is
> in disabled state, because the hardware may assume
> incorrectly that it is then also in low-power state.
>
> To fix this, the controller is kept enabled by taking over
> the IC_ENABLE register. The controller has to be disabled
> when the configuration is updated and when the target
> address or the slave address are assigned, so disabling it
> when IC_CON, IC_TAR or IC_SAR registers are programmed, and
> then re-enabling it again.
>
> Fixes: f0e53aadd702 ("drm/xe: Support for I2C attached MCUs")
> Cc: [email protected]
> Signed-off-by: Heikki Krogerus <[email protected]>
I'll rely on Andy and Mika's disposition on this one.
Raag