This is a note to let you know that I've just added the patch titled
mlxsw: i2c: Fix chunk size setting in output mailbox buffer
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mlxsw-i2c-fix-chunk-size-setting-in-output-mailbox-b.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 225ff6b479f5421acc5a43dae4ea8f9f0dc8db13
Author: Vadim Pasternak <vadimp@xxxxxxxxxx>
Date: Thu Aug 24 15:43:08 2023 +0200
mlxsw: i2c: Fix chunk size setting in output mailbox buffer
[ Upstream commit 146c7c330507c0384bf29d567186632bfe975927 ]
The driver reads commands output from the output mailbox. If the size
of the output mailbox is not a multiple of the transaction /
block size, then the driver will not issue enough read transactions
to read the entire output, which can result in driver initialization
errors.
Fix by determining the number of transactions using DIV_ROUND_UP().
Fixes: 3029a693beda ("mlxsw: i2c: Allow flexible setting of I2C transactions size")
Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxx>
Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxx>
Signed-off-by: Petr Machata <petrm@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/mellanox/mlxsw/i2c.c b/drivers/net/ethernet/mellanox/mlxsw/i2c.c
index ce843ea914646..f20dca41424c9 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/i2c.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/i2c.c
@@ -428,7 +428,7 @@ mlxsw_i2c_cmd(struct device *dev, u16 opcode, u32 in_mod, size_t in_mbox_size,
} else {
/* No input mailbox is case of initialization query command. */
reg_size = MLXSW_I2C_MAX_DATA_SIZE;
- num = reg_size / mlxsw_i2c->block_size;
+ num = DIV_ROUND_UP(reg_size, mlxsw_i2c->block_size);
if (mutex_lock_interruptible(&mlxsw_i2c->cmd.lock) < 0) {
dev_err(&client->dev, "Could not acquire lock");
