Re: [PATCH v1] drm/xe/i2c: Assert/Deassert I2C IRQ

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

On Wed, Mar 18, 2026 at 01:30:29PM +0200, Heikki Krogerus wrote:
> Fri, Mar 13, 2026 at 01:34:38PM +0530, Raag Jadav wrote:
> > I2C IRQ is triggered using virtual wire. Assert/Deassert it in IRQ
> > handler to allow subsequent interrupt generation.
> > 
> > Signed-off-by: Raag Jadav <raag.jadav@intel.com>
> > ---
> >  drivers/gpu/drm/xe/xe_i2c.c | 15 ++++++++++++---
> >  1 file changed, 12 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_i2c.c b/drivers/gpu/drm/xe/xe_i2c.c
> > index 1deb812fe01d..706783863d07 100644
> > --- a/drivers/gpu/drm/xe/xe_i2c.c
> > +++ b/drivers/gpu/drm/xe/xe_i2c.c
> > @@ -176,11 +176,18 @@ static bool xe_i2c_irq_present(struct xe_device *xe)
> >   */
> >  void xe_i2c_irq_handler(struct xe_device *xe, u32 master_ctl)
> >  {
> > -	if (!xe_i2c_irq_present(xe))
> > +	struct xe_mmio *mmio = xe_root_tile_mmio(xe);
> > +
> > +	if (!(master_ctl & I2C_IRQ) || !xe_i2c_irq_present(xe))
> >  		return;
> >  
> > -	if (master_ctl & I2C_IRQ)
> > -		generic_handle_irq_safe(xe->i2c->adapter_irq);
> > +	/* Forward interrupt to I2C adapter */
> > +	generic_handle_irq_safe(xe->i2c->adapter_irq);
> > +
> > +	/* Deassert after I2C adapter clears the interrupt */
> > +	xe_mmio_rmw32(mmio, I2C_CONFIG_CMD, 0, PCI_COMMAND_INTX_DISABLE);
> > +	/* Reassert to allow subsequent interrupt generation */
> > +	xe_mmio_rmw32(mmio, I2C_CONFIG_CMD, PCI_COMMAND_INTX_DISABLE, 0);
> 
> Do we need to do this always, or only with the SMBus Alerts?

For now this is to handle whatever INTR_MASK we're setting in designware
driver, so we atleast have baseline IRQ support until we have smbus ready
(which is essentially a separate discussion).

Raag