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firewire: ohci: use common macro to interpret be32 data in le32 buffer

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The 1394 OHCI driver configures the hardware to transfer the data quadlets
of packet via DMA after converting it to little endian, therefore the data
is typed as __le32. Nevertheless some actual hardware ignores the
configuration. In the case, the data in DMA buffer is aligned to big endian
(__be32).

For the case in big-endian machine, the driver includes the following
interpretation from __le32 to u32 (host-endian = __be32):

    * (__force __u32)(v)

In include/linux/byteorder/generic.h, be32_to_cpu() is available. It is
expanded to the following expression in
'include/uapi/linux/byteorder/big_endian.h':

    * (__force __u32)(__be32)(x)

This commit replace the ad-hoc endian interpretation with the above.

Link: https://lore.kernel.org/r/20240702222034.1378764-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
This commit is contained in:
Takashi Sakamoto 2024-07-03 07:20:30 +09:00
parent 502099acb8
commit f26a38e61c
1 changed files with 1 additions and 1 deletions
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2
drivers/firewire/ohci.c
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@ -876,7 +876,7 @@ static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
#if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
#define cond_le32_to_cpu(v) \
(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
(ohci->quirks & QUIRK_BE_HEADERS ? be32_to_cpu(v) : le32_to_cpu(v))
#else
#define cond_le32_to_cpu(v) le32_to_cpu(v)
#endif