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2020-09-08docs: driver-api: firmware: fallback-mechanisms: Fix rendering of bullet pointJonathan Neuschäfer
Without this patch, the "Firmware is not accessible [...]" line is rendered in bold, which does not seem intentional. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20200905184131.1280337-1-j.neuschaefer@gmx.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20firmware: Add new platform fallback mechanism and firmware_request_platform()Hans de Goede
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>
2018-07-07Documentation: update firmware loader fallback referenceLuis R. Rodriguez
The firmware loader has a fallback mechanism, and it now has some proper kdoc, but we forgot to update the Documentation to use the new kdoc. Fix that. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14Documentation: clarify firmware_class provenance and why we can't rename the ↵Luis R. Rodriguez
module Clarify the provenance of the firmware loader firmware_class module name and why we cannot rename the module in the future. Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14Documentation: fix few typos and clarifications for the firmware loaderLuis R. Rodriguez
Fix a few typos, and clarify a few sentences. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-20rename: _request_firmware_load() fw_load_sysfs_fallback()Luis R. Rodriguez
This reflects much clearer what is being done. While at it, kdoc'ify it. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09firmware: Fix a typo in fallback-mechanisms.rstMasanari Iida
This patch fix a spelling typo found in fallback-mechanisms.rst Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11firmware: revamp firmware documentationLuis R. Rodriguez
Understanding this code is getting out of control without any notes. Give the firmware_class driver a much needed documentation love, and while at it convert it to the new sphinx documentation format. v2: typos and small fixes Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>