sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes

Well, first of all, I don't want to change so many files either.

What I do:
Adding a new parameter "struct bin_attribute *" in the
.read/.write methods for the sysfs binary attributes.

In fact, only the four lines change in fs/sysfs/bin.c and
include/linux/sysfs.h do the real work.
But I have to update all the files that use binary attributes
to make them compatible with the new .read and .write methods.
I'm not sure if I missed any. :(

Why I do this:
For a sysfs attribute, we can get a pointer pointing to the
struct attribute in the .show/.store method,
while we can't do this for the binary attributes.
I don't know why this is different, but this does make it not
so handy to use the binary attributes as the regular ones.
So I think this patch is reasonable. :)

Who benefits from it:
The patch that exposes ACPI tables in sysfs
requires such an improvement.
All the table binary attributes share the same .read method.
Parameter "struct bin_attribute *" is used to get
the table signature and instance number which are used to
distinguish different ACPI table binary attributes.

Without this parameter, we need to offer different .read methods
for different ACPI table binary attributes.
This is impossible as there are various ACPI tables on different
platforms, and we don't know what they are until they are loaded.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 0e511485d2e6..53f0ee6f3016 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -175,7 +175,7 @@ static ssize_t firmware_loading_store(struct device *dev,
 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 
 static ssize_t
-firmware_data_read(struct kobject *kobj,
+firmware_data_read(struct kobject *kobj, struct bin_attribute *bin_attr,
 		   char *buffer, loff_t offset, size_t count)
 {
 	struct device *dev = to_dev(kobj);
@@ -240,7 +240,7 @@ fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
  *	the driver as a firmware image.
  **/
 static ssize_t
-firmware_data_write(struct kobject *kobj,
+firmware_data_write(struct kobject *kobj, struct bin_attribute *bin_attr,
 		    char *buffer, loff_t offset, size_t count)
 {
 	struct device *dev = to_dev(kobj);