FAILED: patch "[PATCH] can: mcp251xfd: mcp251xfd_register_get_dev_id(): fix" failed to apply to 5.15-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 1c0e78a287e3493e22bde8553d02f3b89177eaf7 Mon Sep 17 00:00:00 2001
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: Mon, 20 Jun 2022 11:49:24 +0200
Subject: [PATCH] can: mcp251xfd: mcp251xfd_register_get_dev_id(): fix
 endianness conversion

In mcp251xfd_register_get_dev_id() the device ID register is read with
handcrafted SPI transfers. As all registers, this register is in
little endian. Further it is not naturally aligned in struct
mcp251xfd_map_buf_nocrc::data. However after the transfer the register
content is converted from big endian to CPU endianness not taking care
of being unaligned.

Fix the conversion by converting from little endian to CPU endianness
taking the unaligned source into account.

Side note: So far the register content is 0x0 on all mcp251xfd
compatible chips, and is only used for an informative printk.

Link: https://lore.kernel.org/all/20220627092859.809042-1-mkl@pengutronix.de
Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Reviewed-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
index 3160881e89d9..9b47b07162fe 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -12,6 +12,7 @@
 // Copyright (c) 2019 Martin Sperl <kernel@martin.sperl.org>
 //
 
+#include <asm/unaligned.h>
 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/device.h>
@@ -1787,7 +1788,7 @@ mcp251xfd_register_get_dev_id(const struct mcp251xfd_priv *priv, u32 *dev_id,
 	if (err)
 		goto out_kfree_buf_tx;
 
-	*dev_id = be32_to_cpup((__be32 *)buf_rx->data);
+	*dev_id = get_unaligned_le32(buf_rx->data);
 	*effective_speed_hz_slow = xfer[0].effective_speed_hz;
 	*effective_speed_hz_fast = xfer[1].effective_speed_hz;