You currently need four different kernel builds to test the firmware API fully. By adding a proc knob to force disable the fallback mechanism completely we are able to reduce the amount of kernels you need built to test the firmware API down to two. Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx> --- drivers/base/firmware_fallback.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/base/firmware_fallback.c b/drivers/base/firmware_fallback.c index 1a5bb3d22417..bf63034e0556 100644 --- a/drivers/base/firmware_fallback.c +++ b/drivers/base/firmware_fallback.c @@ -28,12 +28,16 @@ static unsigned int one = 1; * as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y. * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y * functionality on a kernel where that config entry has been disabled. + * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism. + * This emulates the behaviour as if we had set the kernel + * config CONFIG_FW_LOADER_USER_HELPER=n. * @old_timeout: for internal use * @loading_timeout: the timeout to wait for the fallback mechanism before * giving up, in seconds. */ struct firmware_fallback_config { unsigned int force_sysfs_fallback; + unsigned int ignore_sysfs_fallback; int old_timeout; int loading_timeout; }; @@ -54,6 +58,15 @@ struct ctl_table firmware_config_table[] = { .extra1 = &zero, .extra2 = &one, }, + { + .procname = "ignore_sysfs_fallback", + .data = &fw_fallback_config.ignore_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, { } }; EXPORT_SYMBOL_GPL(firmware_config_table); @@ -683,6 +696,11 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { + if (fw_fallback_config.ignore_sysfs_fallback) { + pr_info_once("Ignoring firmware sysfs fallback due to debugfs knob\n"); + return false; + } + if ((opt_flags & FW_OPT_NOFALLBACK)) return false; -- 2.16.1