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ata: libata-transport: fix {dma|pio|xfer}_mode sysfs files

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commit 72aad489f992871e908ff6d9055b26c6366fb864 upstream.

The {dma|pio}_mode sysfs files are incorrectly documented as having a
list of the supported DMA/PIO transfer modes, while the corresponding
fields of the *struct* ata_device hold the transfer mode IDs, not masks.

To match these docs, the {dma|pio}_mode (and even xfer_mode!) sysfs
files are handled by the ata_bitfield_name_match() macro which leads to
reading such kind of nonsense from them:

$ cat /sys/class/ata_device/dev3.0/pio_mode
XFER_UDMA_7, XFER_UDMA_6, XFER_UDMA_5, XFER_UDMA_4, XFER_MW_DMA_4,
XFER_PIO_6, XFER_PIO_5, XFER_PIO_4, XFER_PIO_3, XFER_PIO_2, XFER_PIO_1,
XFER_PIO_0

Using the correct ata_bitfield_name_search() macro fixes that:

$ cat /sys/class/ata_device/dev3.0/pio_mode
XFER_PIO_4

While fixing the file documentation, somewhat reword the {dma|pio}_mode
file doc and add a note about being mostly useful for PATA devices to
the xfer_mode file doc...

Fixes: d9027470b886 ("[libata] Add ATA transport class")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sergey Shtylyov 2022-06-08 22:51:07 +03:00 committed by Greg Kroah-Hartman
parent 43d7093525
commit 94ac2a94b7
2 changed files with 4 additions and 3 deletions
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5
Documentation/ABI/testing/sysfs-ata
View File

@ -59,17 +59,18 @@ class
dma_mode
Transfer modes supported by the device when in DMA mode.
DMA transfer mode used by the device.
Mostly used by PATA device.
pio_mode
Transfer modes supported by the device when in PIO mode.
PIO transfer mode used by the device.
Mostly used by PATA device.
xfer_mode
Current transfer mode.
Mostly used by PATA device.
id

2
drivers/ata/libata-transport.c
View File

@ -196,7 +196,7 @@ static struct {
{ XFER_PIO_0, "XFER_PIO_0" },
{ XFER_PIO_SLOW, "XFER_PIO_SLOW" }
};
ata_bitfield_name_match(xfer,ata_xfer_names)
ata_bitfield_name_search(xfer, ata_xfer_names)
/*
* ATA Port attributes