Commit 641511bf authored by Eddie James's avatar Eddie James Committed by Joel Stanley
Browse files

fsi: core: Fix legacy minor numbering 



The legacy minor numbering shifts the chip id too much,
resulting in ids that overlap with regular ids. Since there
are only 2 bits for 4 types, only shift the chip id by 2
to fit the legacy ids in their reserved space.

Signed-off-by: default avatarEddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20230612195657.245125-10-eajames@linux.ibm.com


Signed-off-by: default avatarJoel Stanley <joel@jms.id.au>
parent 02c8fec0

drivers/fsi/fsi-core.c

+8 −3
Original line number Diff line number Diff line
@@ -913,8 +913,12 @@ static int __fsi_get_new_minor(struct fsi_slave *slave, enum fsi_dev_type type, 


	/* Check if we qualify for legacy numbering */

	if (cid >= 0 && cid < 16 && type < 4) {

		/* Try reserving the legacy number */

		id = (cid << 4) | type;

		/*

		 * Try reserving the legacy number, which has 0 - 0x3f reserved

		 * in the ida range. cid goes up to 0xf and type contains two

		 * bits, so construct the id with the below two bit shift.

		 */

		id = (cid << 2) | type;

		id = ida_simple_get(&fsi_minor_ida, id, id + 1, GFP_KERNEL);

		if (id >= 0) {

			*out_index = fsi_adjust_index(cid);
@@ -949,7 +953,8 @@ int fsi_get_new_minor(struct fsi_device *fdev, enum fsi_dev_type type, 
		int aid = of_alias_get_id(fdev->dev.of_node, fsi_dev_type_names[type]);



		if (aid >= 0) {

			int id = (aid << 4) | type;

			/* Use the same scheme as the legacy numbers. */

			int id = (aid << 2) | type;



			id = ida_simple_get(&fsi_minor_ida, id, id + 1, GFP_KERNEL);

			if (id >= 0) {