serial: 8250: Keep 8250.<xxxx> module options functional after driver rename

With commit 835d844d1 (8250_pnp: do pnp probe before legacy probe), the
8250 driver was renamed to 8250_core.  This means any existing usage of
the 8259.<xxxx> module parameters or as a kernel command line switch is
now broken, as the 8250_core driver doesn't parse options belonging to
something called "8250".

To solve this, we redefine the module options in a dummy function using
a redefined MODULE_PARAM_PREFX when built into the kernel.  In the case
where we're building as a module, we provide an alias to the old 8250
name.  The dummy function prevents compiler errors due to global variable
redefinitions that happen as part of the module_param_ macro expansions.

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Josh Boyer 2013-03-10 10:33:40 -04:00 committed by Greg Kroah-Hartman
parent 827aa0d36d
commit f2b8dfd9e4

View File

@ -3417,3 +3417,32 @@ module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444);
MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA");
#endif
MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR);
#ifndef MODULE
/* This module was renamed to 8250_core in 3.7. Keep the old "8250" name
* working as well for the module options so we don't break people. We
* need to keep the names identical and the convenient macros will happily
* refuse to let us do that by failing the build with redefinition errors
* of global variables. So we stick them inside a dummy function to avoid
* those conflicts. The options still get parsed, and the redefined
* MODULE_PARAM_PREFIX lets us keep the "8250." syntax alive.
*
* This is hacky. I'm sorry.
*/
static void __used s8250_options(void)
{
#undef MODULE_PARAM_PREFIX
#define MODULE_PARAM_PREFIX "8250."
module_param_cb(share_irqs, &param_ops_uint, &share_irqs, 0644);
module_param_cb(nr_uarts, &param_ops_uint, &nr_uarts, 0644);
module_param_cb(skip_txen_test, &param_ops_uint, &skip_txen_test, 0644);
#ifdef CONFIG_SERIAL_8250_RSA
__module_param_call(MODULE_PARAM_PREFIX, probe_rsa,
&param_array_ops, .arr = &__param_arr_probe_rsa,
0444, -1);
#endif
}
#else
MODULE_ALIAS("8250");
#endif