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

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

Fri, Mar 13, 2026 at 01:34:38PM +0530, Raag Jadav kirjoitti:
> 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>

Looks good to me. FWIW:

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.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);
>  }
>  
>  void xe_i2c_irq_reset(struct xe_device *xe)
> @@ -190,6 +197,7 @@ void xe_i2c_irq_reset(struct xe_device *xe)
>  	if (!xe_i2c_irq_present(xe))
>  		return;
>  
> +	xe_mmio_rmw32(mmio, I2C_CONFIG_CMD, 0, PCI_COMMAND_INTX_DISABLE);
>  	xe_mmio_rmw32(mmio, I2C_BRIDGE_PCICFGCTL, ACPI_INTR_EN, 0);
>  }
>  
> @@ -201,6 +209,7 @@ void xe_i2c_irq_postinstall(struct xe_device *xe)
>  		return;
>  
>  	xe_mmio_rmw32(mmio, I2C_BRIDGE_PCICFGCTL, 0, ACPI_INTR_EN);
> +	xe_mmio_rmw32(mmio, I2C_CONFIG_CMD, PCI_COMMAND_INTX_DISABLE, 0);
>  }
>  
>  static int xe_i2c_irq_map(struct irq_domain *h, unsigned int virq,
> -- 
> 2.43.0

-- 
heikki