Commit 036105e3 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

video: Provide screen_info_get_pci_dev() to find screen_info's PCI device 



Add screen_info_get_pci_dev() to find the PCI device of an instance
of screen_info. Does nothing on systems without PCI bus.

v3:
	* search PCI device with pci_get_base_class() (Sui)
v2:
	* remove ret from screen_info_pci_dev() (Javier)

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240212090736.11464-3-tzimmermann@suse.de
parent 75fa9b7e

drivers/video/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ obj-$(CONFIG_VIDEO) += cmdline.o nomodeset.o 
obj-$(CONFIG_HDMI)                += hdmi.o



screen_info-y			  := screen_info_generic.o

screen_info-$(CONFIG_PCI)         += screen_info_pci.o



obj-$(CONFIG_VT)		  += console/

obj-$(CONFIG_FB_STI)		  += console/

drivers/video/screen_info_pci.c

0 → 100644
+48 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/pci.h>

#include <linux/screen_info.h>



static struct pci_dev *__screen_info_pci_dev(struct resource *res)

{

	struct pci_dev *pdev = NULL;

	const struct resource *r = NULL;



	if (!(res->flags & IORESOURCE_MEM))

		return NULL;



	while (!r && (pdev = pci_get_base_class(PCI_BASE_CLASS_DISPLAY, pdev))) {

		r = pci_find_resource(pdev, res);

	}



	return pdev;

}



/**

 * screen_info_pci_dev() - Return PCI parent device that contains screen_info's framebuffer

 * @si: the screen_info

 *

 * Returns:

 * The screen_info's parent device or NULL on success, or a pointer-encoded

 * errno value otherwise. The value NULL is not an error. It signals that no

 * PCI device has been found.

 */

struct pci_dev *screen_info_pci_dev(const struct screen_info *si)

{

	struct resource res[SCREEN_INFO_MAX_RESOURCES];

	ssize_t i, numres;



	numres = screen_info_resources(si, res, ARRAY_SIZE(res));

	if (numres < 0)

		return ERR_PTR(numres);



	for (i = 0; i < numres; ++i) {

		struct pci_dev *pdev = __screen_info_pci_dev(&res[i]);



		if (pdev)

			return pdev;

	}



	return NULL;

}

EXPORT_SYMBOL(screen_info_pci_dev);

include/linux/screen_info.h

+10 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
 */

#define SCREEN_INFO_MAX_RESOURCES	3



struct pci_dev;

struct resource;



static inline bool __screen_info_has_lfb(unsigned int type)
@@ -104,6 +105,15 @@ static inline unsigned int screen_info_video_type(const struct screen_info *si) 


ssize_t screen_info_resources(const struct screen_info *si, struct resource *r, size_t num);



#if defined(CONFIG_PCI)

struct pci_dev *screen_info_pci_dev(const struct screen_info *si);

#else

static inline struct pci_dev *screen_info_pci_dev(const struct screen_info *si)

{

	return NULL;

}

#endif



extern struct screen_info screen_info;



#endif /* _SCREEN_INFO_H */