diff options
Diffstat (limited to 'drivers/ide/ide-timings.c')
| -rw-r--r-- | drivers/ide/ide-timings.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/ide/ide-timings.c b/drivers/ide/ide-timings.c index ebef6d4e3f6..8c2f8327f48 100644 --- a/drivers/ide/ide-timings.c +++ b/drivers/ide/ide-timings.c @@ -1,5 +1,6 @@ /* * Copyright (c) 1999-2001 Vojtech Pavlik + * Copyright (c) 2007-2008 Bartlomiej Zolnierkiewicz * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -75,6 +76,27 @@ struct ide_timing *ide_timing_find_mode(u8 speed) } EXPORT_SYMBOL_GPL(ide_timing_find_mode); +u16 ide_pio_cycle_time(ide_drive_t *drive, u8 pio) +{ + struct hd_driveid *id = drive->id; + struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio); + u16 cycle = 0; + + if (id->field_valid & 2) { + if (id->capability & 8) + cycle = id->eide_pio_iordy; + else + cycle = id->eide_pio; + + /* conservative "downgrade" for all pre-ATA2 drives */ + if (pio < 3 && cycle < t->cycle) + cycle = 0; /* use standard timing */ + } + + return cycle ? cycle : t->cycle; +} +EXPORT_SYMBOL_GPL(ide_pio_cycle_time); + #define ENOUGH(v, unit) (((v) - 1) / (unit) + 1) #define EZ(v, unit) ((v) ? ENOUGH(v, unit) : 0) |