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From:   Eddie James <eajames@linux.ibm.com>
To:     linux-fsi@lists.ozlabs.org
Cc:     linux-kernel@vger.kernel.org, joel@jms.id.au, jk@ozlabs.org,
        alistair@popple.id.au, Eddie James <eajames@linux.ibm.com>
Subject: [PATCH] fsi: core: Fix legacy minor numbering
Date:   Thu, 13 Apr 2023 11:24:40 -0500
Message-Id: <20230413162440.3313036-1-eajames@linux.ibm.com>
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FSI reserves the first 64 minor numbers for the legacy numbering
based on the chip id. However the legacy number shifts the chip
id too much, resulting in overlap between legacy and non-legacy
numbers. Reduce the chip id bit shift since the type field only
takes 2 bits.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/fsi/fsi-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index 0b927c9f4267..b9f410170655 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -950,7 +950,7 @@ 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;
+		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);
-- 
2.31.1