Re: Getting request_firmware() filename info from user space

From: Clemens Ladisch
Date: Tue Jun 21 2011 - 03:55:39 EST

Peter Hsiang wrote:
> Using the kernel request_firmware() function, it seems one can send any file by:
> cat myfile.bin > /sys/class/firmware/xxxx/data
> How does the user space code obtain the filename parameter specified in the request_firmware() call?
> The documentation says $DEVPATH and $FIRMWARE variables are provided in
> the environment, but "echo $FIRMWARE" prints an empty string.

drivers/base/firmware_class.c has:

static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
struct firmware_priv *fw_priv = to_firmware_priv(dev);

if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->fw_id))
return -ENOMEM;
if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
return -ENOMEM;
if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
return -ENOMEM;

return 0;

Are these available at least in the udev rule?

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