From: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx> Subject: [PATCH] pata_cypress: fix PIO timings underclocking Timing registers should be programmed with the desired number of clocks minus one clock. Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx> --- drivers/ata/pata_cypress.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) Index: b/drivers/ata/pata_cypress.c =================================================================== --- a/drivers/ata/pata_cypress.c +++ b/drivers/ata/pata_cypress.c @@ -62,14 +62,16 @@ static void cy82c693_set_piomode(struct return; } - time_16 = clamp_val(t.recover, 0, 15) | (clamp_val(t.active, 0, 15) << 4); - time_8 = clamp_val(t.act8b, 0, 15) | (clamp_val(t.rec8b, 0, 15) << 4); + time_16 = clamp_val(t.recover - 1, 0, 15) | + (clamp_val(t.active - 1, 0, 15) << 4); + time_8 = clamp_val(t.act8b - 1, 0, 15) | + (clamp_val(t.rec8b - 1, 0, 15) << 4); if (adev->devno == 0) { pci_read_config_dword(pdev, CY82_IDE_ADDRSETUP, &addr); addr &= ~0x0F; /* Mask bits */ - addr |= clamp_val(t.setup, 0, 15); + addr |= clamp_val(t.setup - 1, 0, 15); pci_write_config_dword(pdev, CY82_IDE_ADDRSETUP, addr); pci_write_config_byte(pdev, CY82_IDE_MASTER_IOR, time_16); @@ -79,7 +81,7 @@ static void cy82c693_set_piomode(struct pci_read_config_dword(pdev, CY82_IDE_ADDRSETUP, &addr); addr &= ~0xF0; /* Mask bits */ - addr |= (clamp_val(t.setup, 0, 15) << 4); + addr |= (clamp_val(t.setup - 1, 0, 15) << 4); pci_write_config_dword(pdev, CY82_IDE_ADDRSETUP, addr); pci_write_config_byte(pdev, CY82_IDE_SLAVE_IOR, time_16); -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html