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can: mcp251xfd: mcp251xfd_register_get_dev_id(): fix endianness conversion

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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: 55e5b97f00 ("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>
This commit is contained in:
Marc Kleine-Budde 2022-06-20 11:49:24 +02:00
parent 0ff32bfa0e
commit 1c0e78a287
1 changed files with 2 additions and 1 deletions
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3
drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
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@ -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;