mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
e4c2c0ff00
In some cases the platform's main firmware (e.g. the UEFI fw) may contain an embedded copy of device firmware which needs to be (re)loaded into the peripheral. Normally such firmware would be part of linux-firmware, but in some cases this is not feasible, for 2 reasons: 1) The firmware is customized for a specific use-case of the chipset / use with a specific hardware model, so we cannot have a single firmware file for the chipset. E.g. touchscreen controller firmwares are compiled specifically for the hardware model they are used with, as they are calibrated for a specific model digitizer. 2) Despite repeated attempts we have failed to get permission to redistribute the firmware. This is especially a problem with customized firmwares, these get created by the chip vendor for a specific ODM and the copyright may partially belong with the ODM, so the chip vendor cannot give a blanket permission to distribute these. This commit adds a new platform fallback mechanism to the firmware loader which will try to lookup a device fw copy embedded in the platform's main firmware if direct filesystem lookup fails. Drivers which need such embedded fw copies can enable this fallback mechanism by using the new firmware_request_platform() function. Note that for now this is only supported on EFI platforms and even on these platforms firmware_fallback_platform() only works if CONFIG_EFI_EMBEDDED_FIRMWARE is enabled (this gets selected by drivers which need this), in all other cases firmware_fallback_platform() simply always returns -ENOENT. Reported-by: Dave Olsthoorn <dave@bewaar.me> Suggested-by: Peter Jones <pjones@redhat.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200115163554.101315-5-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
110 lines
2.9 KiB
C
110 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_FIRMWARE_H
|
|
#define _LINUX_FIRMWARE_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/gfp.h>
|
|
|
|
#define FW_ACTION_NOHOTPLUG 0
|
|
#define FW_ACTION_HOTPLUG 1
|
|
|
|
struct firmware {
|
|
size_t size;
|
|
const u8 *data;
|
|
struct page **pages;
|
|
|
|
/* firmware loader private fields */
|
|
void *priv;
|
|
};
|
|
|
|
struct module;
|
|
struct device;
|
|
|
|
struct builtin_fw {
|
|
char *name;
|
|
void *data;
|
|
unsigned long size;
|
|
};
|
|
|
|
/* We have to play tricks here much like stringify() to get the
|
|
__COUNTER__ macro to be expanded as we want it */
|
|
#define __fw_concat1(x, y) x##y
|
|
#define __fw_concat(x, y) __fw_concat1(x, y)
|
|
|
|
#define DECLARE_BUILTIN_FIRMWARE(name, blob) \
|
|
DECLARE_BUILTIN_FIRMWARE_SIZE(name, &(blob), sizeof(blob))
|
|
|
|
#define DECLARE_BUILTIN_FIRMWARE_SIZE(name, blob, size) \
|
|
static const struct builtin_fw __fw_concat(__builtin_fw,__COUNTER__) \
|
|
__used __section(.builtin_fw) = { name, blob, size }
|
|
|
|
#if defined(CONFIG_FW_LOADER) || (defined(CONFIG_FW_LOADER_MODULE) && defined(MODULE))
|
|
int request_firmware(const struct firmware **fw, const char *name,
|
|
struct device *device);
|
|
int firmware_request_nowarn(const struct firmware **fw, const char *name,
|
|
struct device *device);
|
|
int firmware_request_platform(const struct firmware **fw, const char *name,
|
|
struct device *device);
|
|
int request_firmware_nowait(
|
|
struct module *module, bool uevent,
|
|
const char *name, struct device *device, gfp_t gfp, void *context,
|
|
void (*cont)(const struct firmware *fw, void *context));
|
|
int request_firmware_direct(const struct firmware **fw, const char *name,
|
|
struct device *device);
|
|
int request_firmware_into_buf(const struct firmware **firmware_p,
|
|
const char *name, struct device *device, void *buf, size_t size);
|
|
|
|
void release_firmware(const struct firmware *fw);
|
|
#else
|
|
static inline int request_firmware(const struct firmware **fw,
|
|
const char *name,
|
|
struct device *device)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int firmware_request_nowarn(const struct firmware **fw,
|
|
const char *name,
|
|
struct device *device)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int firmware_request_platform(const struct firmware **fw,
|
|
const char *name,
|
|
struct device *device)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int request_firmware_nowait(
|
|
struct module *module, bool uevent,
|
|
const char *name, struct device *device, gfp_t gfp, void *context,
|
|
void (*cont)(const struct firmware *fw, void *context))
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline void release_firmware(const struct firmware *fw)
|
|
{
|
|
}
|
|
|
|
static inline int request_firmware_direct(const struct firmware **fw,
|
|
const char *name,
|
|
struct device *device)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int request_firmware_into_buf(const struct firmware **firmware_p,
|
|
const char *name, struct device *device, void *buf, size_t size)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
#endif
|
|
|
|
int firmware_request_cache(struct device *device, const char *name);
|
|
|
|
#endif
|