Re: [PATCH 5/8] firmware/sysfb: Create firmware device only for enabled PCI devices

[Javier Martinez Canillas <javierm@redhat.com>]

Thomas Zimmermann <tzimmermann@suse.de> writes:

> Test if the firmware framebuffer's parent PCI device, if any, has
> been enabled. If not, the firmware framebuffer is most likely not
> working. Hence, do not create a device for the firmware framebuffer
> on disabled PCI devices.
>
> So far, efifb tracked the status of the PCI parent device internally
> and did not bind if it was disabled. This patch implements the
> functionality for all firmware framebuffers.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---

[...]

>  
> +static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
> +{
> +#if defined(CONFIG_PCI)
> +	/*
> +	 * TODO: Try to integrate this code into the PCI subsystem
> +	 */
> +	int ret;
> +	u16 command;
> +
> +	ret = pci_read_config_word(pdev, PCI_COMMAND, &command);
> +	if (ret != PCIBIOS_SUCCESSFUL)
> +		return false;
> +	if (!(command & PCI_COMMAND_MEMORY))
> +		return false;
> +	return true;
> +#else
> +	// Getting here without PCI support is probably a bug.
> +	return false;

Should we warn before return in this case ?

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat