ata_acpi_gtm_xfermask() as separated out from pacpi_discover_modes()
has various bugs. Fix them.
* The wrong comparison operator is used when finding for matching
cycle resulting totally bogus result.
* With the comparion operator fixed, boundary condtion handling is
clumsy.
* Setting of any DMA mask bit set all bits in PIO mask.
* MWDMA and UDMA blocks are swapped.
Signed-off-by: Tejun Heo <htejun@xxxxxxxxx>
Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
---
drivers/ata/libata-acpi.c | 42 +++++++++++++++++++++---------------------
1 files changed, 21 insertions(+), 21 deletions(-)
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index d6697ba..9f0b208 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -473,49 +473,49 @@ EXPORT_SYMBOL_GPL(ata_acpi_udma_cycle);
unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
const struct ata_acpi_gtm *gtm)
{
+ unsigned long pio_mask = 0, mwdma_mask = 0, udma_mask = 0;
int unit, i;
u32 t;
- unsigned long mask = (0x7f << ATA_SHIFT_UDMA) | (0x7 << ATA_SHIFT_MWDMA) | (0x1F << ATA_SHIFT_PIO);
/* we always use the 0 slot for crap hardware */
unit = dev->devno;
if (!(gtm->flags & 0x10))
unit = 0;
+ /* Values larger than the longest cycle results in 0 mask
+ * while values equal to smaller than the shortest cycle
+ * results in mask which includes all supported modes.
+ * Disabled transfer method has the value of 0xffffffff which
+ * will always result in 0 mask.
+ */
+
/* start by scanning for PIO modes */
- for (i = 0; i < 7; i++) {
- t = gtm->drive[unit].pio;
- if (t <= ata_acpi_pio_cycle[i]) {
- mask |= (2 << (ATA_SHIFT_PIO + i)) - 1;
+ t = gtm->drive[unit].pio;
+ for (i = 0; i < ARRAY_SIZE(ata_acpi_pio_cycle); i++)
+ if (t > ata_acpi_pio_cycle[i])
break;
- }
- }
+ pio_mask = (1 << i) - 1;
/* See if we have MWDMA or UDMA data. We don't bother with
* MWDMA if UDMA is available as this means the BIOS set UDMA
* and our error changedown if it works is UDMA to PIO anyway.
*/
- if (gtm->flags & (1 << (2 * unit))) {
+ t = gtm->drive[unit].dma;
+ if (!(gtm->flags & (1 << (2 * unit)))) {
/* MWDMA */
- for (i = 0; i < 5; i++) {
- t = gtm->drive[unit].dma;
- if (t <= ata_acpi_mwdma_cycle[i]) {
- mask |= (2 << (ATA_SHIFT_MWDMA + i)) - 1;
+ for (i = 0; i < ARRAY_SIZE(ata_acpi_mwdma_cycle); i++)
+ if (t > ata_acpi_mwdma_cycle[i])
break;
- }
- }
+ mwdma_mask = (1 << i) - 1;
} else {
/* UDMA */
- for (i = 0; i < 7; i++) {
- t = gtm->drive[unit].dma;
- if (t <= ata_acpi_udma_cycle[i]) {
- mask |= (2 << (ATA_SHIFT_UDMA + i)) - 1;
+ for (i = 0; i < ARRAY_SIZE(ata_acpi_udma_cycle); i++)
+ if (t > ata_acpi_udma_cycle[i])
break;
- }
- }
+ udma_mask = (1 << i) - 1;
}
- return mask;
+ return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
}
EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);
--
1.5.2.4
-
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