Re: [PATCH drm/hisilicon 1/2] drm/irq: Add the new api to enable pci msi

From: Daniel Vetter
Date: Tue Dec 15 2020 - 06:58:47 EST


On Tue, Dec 15, 2020 at 07:48:52PM +0800, Tian Tao wrote:
> Add new api devm_drm_msi_install() to register interrupts,
> no need to call pci_disable_msi() when the drm module is removed.
>
> Signed-off-by: Tian Tao <tiantao6@xxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_irq.c | 33 +++++++++++++++++++++++++++++++++
> include/drm/drm_irq.h | 1 +
> 2 files changed, 34 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
> index 803af4b..da58b2c 100644
> --- a/drivers/gpu/drm/drm_irq.c
> +++ b/drivers/gpu/drm/drm_irq.c
> @@ -246,6 +246,39 @@ int devm_drm_irq_install(struct drm_device *dev, int irq)
> }
> EXPORT_SYMBOL(devm_drm_irq_install);
>
> +static void devm_drm_msi_uninstall(void *data)
> +{
> + struct drm_device *dev = (struct drm_device *)data;
> +
> + pci_disable_msi(dev->pdev);

This should be in the pci core, not in drm.
-Daniel

> +}
> +
> +/**
> + * devm_drm_msi_install - install IRQ handler
> + * @dev: DRM device
> + *
> + * devm_drm_msi_install is a help function of pci_enable_msi.
> + *
> + * if the driver uses devm_drm_msi_install, there is no need
> + * to call pci_disable_msi when the drm module get unloaded,
> + * as this will done automagically.
> + *
> + * Returns:
> + * Zero on success or a negative error code on failure.
> + */
> +int devm_drm_msi_install(struct drm_device *dev)
> +{
> + int ret;
> +
> + ret = pci_enable_msi(dev->pdev);
> + if (ret)
> + return ret;
> +
> + return devm_add_action_or_reset(dev->dev,
> + devm_drm_msi_uninstall, dev);
> +}
> +EXPORT_SYMBOL(devm_drm_msi_install);
> +
> #if IS_ENABLED(CONFIG_DRM_LEGACY)
> int drm_legacy_irq_control(struct drm_device *dev, void *data,
> struct drm_file *file_priv)
> diff --git a/include/drm/drm_irq.h b/include/drm/drm_irq.h
> index 631b22f..c8dff45 100644
> --- a/include/drm/drm_irq.h
> +++ b/include/drm/drm_irq.h
> @@ -29,4 +29,5 @@ struct drm_device;
> int drm_irq_install(struct drm_device *dev, int irq);
> int drm_irq_uninstall(struct drm_device *dev);
> int devm_drm_irq_install(struct drm_device *dev, int irq);
> +int devm_drm_msi_install(struct drm_device *dev);
> #endif
> --
> 2.7.4
>

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch