ide: add ide_use_fast_pio() helper (v3)
* add ide_use_fast_pio() helper for use by host drivers
* add DMA capability and hwif->autodma checks to ide_use_dma()
- au1xxx-ide/it8213/it821x drivers didn't check for (id->capability & 1)
[ for the IT8211/2 in SMART mode this check shouldn't be made but since
in it821x_fixups() we set DMA bit explicitly:
if(strstr(id->model, "Integrated Technology Express")) {
/* In raid mode the ident block is slightly buggy
We need to set the bits so that the IDE layer knows
LBA28. LBA48 and DMA ar valid */
id->capability |= 3; /* LBA28, DMA */
we are better off using generic helper if we can ]
- ide-cris driver didn't set ->autodma
[ before the patch hwif->autodma was only checked in the chipset specific
hwif->ide_dma_check implementations, for ide-cris it is cris_dma_check()
function so there no behavior change here ]
v2:
* updated patch description (thanks to Alan Cox for the feedback)
v3:
* updated for scc_pata driver
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index bea5e13..8afce4c 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -205,6 +205,21 @@
EXPORT_SYMBOL(ide_dma_enable);
+int ide_use_fast_pio(ide_drive_t *drive)
+{
+ struct hd_driveid *id = drive->id;
+
+ if ((id->capability & 1) && drive->autodma)
+ return 1;
+
+ if ((id->capability & 8) || (id->field_valid & 2))
+ return 1;
+
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(ide_use_fast_pio);
+
/*
* Standard (generic) timings for PIO modes, from ATA2 specification.
* These timings are for access to the IDE data port register *only*.