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

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: c26b4896cb0c ("[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>

diff --git a/Documentation/ABI/testing/sysfs-ata b/Documentation/ABI/testing/sysfs-ata
index 2f726c91475223b8263ba6b1a319649bf9e48a14..3daecac48964feb54193286f75e7a2acf516d5dc 100644 (file)
--- a/Documentation/ABI/testing/sysfs-ata
+++ b/Documentation/ABI/testing/sysfs-ata
@@ -107,13 +107,14 @@ Description:
                                described in ATA8 7.16 and 7.17. Only valid if
                                the device is not a PM.
 
-               pio_mode:       (RO) Transfer modes supported by the device when
-                               in PIO mode. Mostly used by PATA device.
+               pio_mode:       (RO) PIO transfer mode used by the device.
+                               Mostly used by PATA devices.
 
-               xfer_mode:      (RO) Current transfer mode
+               xfer_mode:      (RO) Current transfer mode. Mostly used by
+                               PATA devices.
 
-               dma_mode:       (RO) Transfer modes supported by the device when
-                               in DMA mode. Mostly used by PATA device.
+               dma_mode:       (RO) DMA transfer mode used by the device.
+                               Mostly used by PATA devices.
 
                class:          (RO) Device class. Can be "ata" for disk,
                                "atapi" for packet device, "pmp" for PM, or

diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index ca129854a88c77a7301ece33fc9d73d3f3b218d6..c380278874990da00407353edc5a19c5c059f3de 100644 (file)
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -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