Re: [PATCH v6 0/3] drm/xe/i2c: alerts and controller enabling modifications

[Raag Jadav <raag.jadav@intel.com>]

On Tue, Jul 28, 2026 at 05:50:51PM +0200, Heikki Krogerus wrote:
> On Wed, Jul 22, 2026 at 03:35:51PM +0200, Heikki Krogerus wrote:
> > Hi,
> > 
> > Changed since v5:
> > - Leaving the interrupt de-asserting to the firmware.
> > - Re-asserting the interrupt before declaring the device wedged.
> > - Preventing the SMBus Alert from being masked.
> > 
> > v5: https://lore.kernel.org/lkml/20260715153153.1243751-1-heikki.krogerus@linux.intel.com/
> > v4: https://lore.kernel.org/lkml/20260713155601.711389-1-heikki.krogerus@linux.intel.com/
> > v2: https://lore.kernel.org/lkml/20260625125939.429078-1-heikki.krogerus@linux.intel.com/
> > v1: https://lore.kernel.org/lkml/20260622114759.3464047-1-heikki.krogerus@linux.intel.com/
> > 
> > Heikki Krogerus (3):
> >   i2c: designware: Global register definitions
> >   drm/xe/i2c: Fix the interrupt handling
> >   drm/xe/i2c: Keep the i2c controller always enabled
> > 
> >  MAINTAINERS                                |   1 +
> >  drivers/gpu/drm/xe/Makefile                |   4 +-
> >  drivers/gpu/drm/xe/regs/xe_i2c_regs.h      |   2 +
> >  drivers/gpu/drm/xe/xe_amc.c                | 187 +++++++++++++++++++++
> >  drivers/gpu/drm/xe/xe_amc.h                |  25 +++
> >  drivers/gpu/drm/xe/xe_i2c.c                | 165 +++++++++---------
> >  drivers/gpu/drm/xe/xe_i2c.h                |  14 +-
> >  drivers/i2c/busses/i2c-designware-common.c |   2 +
> >  drivers/i2c/busses/i2c-designware-core.h   |  85 +---------
> >  drivers/i2c/busses/i2c-designware-master.c |   2 +
> >  drivers/i2c/busses/i2c-designware-slave.c  |   2 +
> >  include/linux/designware_i2c.h             | 107 ++++++++++++
> >  12 files changed, 431 insertions(+), 165 deletions(-)
> >  create mode 100644 drivers/gpu/drm/xe/xe_amc.c
> >  create mode 100644 drivers/gpu/drm/xe/xe_amc.h
> >  create mode 100644 include/linux/designware_i2c.h
> 
> One more fix is needed for this series. Raag noticed that the i2c
> driver accesses the registers after the drm device is declared wedget.
> The i2c adapter is suspended after the device is declared wedged, and
> the driver's suspend callback then accesses the registers.

There are usecases for possible adapter access after the device is
declared wedged, so this requires more factors to be considered. I'll
take a look at it as a follow up once I'm done with RAS.

Let's get this one through for now.

Raag