USB: g_mass_storage: fsg_config added & module params handlig changed

Removed all references to mod_data in f_mass_storage.c and
instead created fsg_config structure fsg_common_init() takes
as an argument -- it stores all configuration options that
were previously taken from mod_data.

Moreover, The fsg_config structure allows per-LUN
configuration of removable and CD-ROM emulation.

Module parameters are handled by defining an object of
fsg_module_parameters structure and then declaring module
parameters via FSG_MODULE_PARAMETERS() macro.  It adds proper
declarations to the code making specified object be populated
from module parameters.

To use values stored there one may use either
fsg_config_from_params() which will will a fsg_config structure
with values taken from fsg_module_parameters structure or
fsg_common_from_params() which will initialise fsg_common
structure directly.
Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/mass_storage.c

@@ -127,6 +127,11 @@ static struct usb_gadget_strings *dev_strings[] = {
 
 /****************************** Configurations ******************************/
 
+static struct fsg_module_parameters mod_data = {
+	.stall = 1
+};
+FSG_MODULE_PARAMETERS(/* no prefix */, mod_data);
+
 static int __init msg_do_config(struct usb_configuration *c)
 {
 	struct fsg_common *common;
@@ -137,7 +142,7 @@ static int __init msg_do_config(struct usb_configuration *c)
 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 	}
 
-	common = fsg_common_init(0, c->cdev);
+	common = fsg_common_from_params(0, c->cdev, &mod_data);
 	if (IS_ERR(common))
 		return PTR_ERR(common);