When we get an SDB FIS with the 'N' bit set, we should send
an event to user space to indicate that there has been a
media change. This will be done via the scsi device.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Check to see if an ATAPI device supports Asynchronous Notification.
If so, enable it, if the host controller supports AN.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Set the MWDMA timing by updating the correct registers. Split the PIO path as
this is mostly shared code. Wants testing.
Signed-off-by: Alan Cox <alan@redhat.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Remembered this while doing auditing and code review versus the specs
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add support for issuing ATA_16 passthru commands to ATAPI devices
managed by libata. It requires the previous CDB length fix patch.
A boot/module parameter, "atapi_passthru16=0" can be used to globally
disable this feature, if ever desired.
tj: restructured __ata_scsi_queuecmd() according to Jeff's suggestion.
Signed-off-by: Mark Lord <liml@rtr.ca>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Move ata_altstatus() out from ata_hsm_move() to the pio data xfer
functions like ata_pio_sectors() and atapi_pio_bytes() where it makes
more sense.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Debugging a report of a problem with an ancient solid state disk showed
up some problems in the IORDY handling
1. We check the wrong bit to see if the device has IORDY
2. Even then some ancient creaking piles of crap don't support
SETXFER at all.
The cases it fixes are obscure and the risk of side effects is slight
but possible. This also moves us slightly closer to supporting original
MFM/RLL disks with libata.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update hotplug to handle PMP links. When PMP is attached, the PMP
number corresponds to C of SCSI H:C:I:L. While at it, change argument
to ata_find_dev() to @devno from @id to avoid confusion with SCSI
device ID.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update ata_eh_autopsy(), ata_eh_report(),
ata_eh_revalidate_and_attach() and ata_eh_recover() to deal with PMP
links. ata_eh_autopsy() and ata_eh_report() updates are
straightforward. They just repeat the same operation over all
configured links. The only change to ata_eh_revalidate_and_attach()
is avoiding calling ->cable_select() on non-host ports.
ata_eh_recover() update is more complex as it first processes all
resets and then performs the rest. This is necessary as thawing with
some links in unknown state can be dangerous. ehi->action is cleared
on successful recovery of a link to avoid repeating recovery due to
failures in other links.
ata_eh_recover() iterates over only PMP links if PMP is attached, and,
on failure, the failing link is returned in @failed_link instead of
disabling devices directly. These are to integrate ata_eh_recover()
into PMP EH later.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update ata_scsi_error() to handle PMP links. As error conditions can
occur on both host and PMP links, __ata_port_for_each_link() is used.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add link->pmp, ap->nr_pmp_links, ap->pmp_link[], and implement/update
link helpers.
printk helpers are updated such that port and link are identifed as
'ataP:' if no PMP is attached, while device is identified as
'ataP.DD:'. If PMP is attached, they become 'ataP:', 'ataP.LL:' and
'ataP.LL' - ie. link and device are identified their PMP number.
If PPM is attached (ap->nr_pmp_links != 0), ata_for_each_link()
iterates over PMP links, while __ata_for_each_link() iterates over the
host link + PMP links. If PMP is not attached (ap->nr_pmp_links ==
0), both iterate over only the host link.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out link initialization into ata_link_init() and
ata_link_init_sata_spd().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
HRST_TO_RESUME and SKIP_D2H_BSY are link attributes. Move them to
ata_link->flags. This will allow host and PMP links to have different
attributes. ata_port_info->link_flags is added and used by LLDs to
specify these flags during initialization.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make the following functions deal with ata_link instead of ata_port.
* ata_set_mode()
* ata_eh_autopsy() and related functions
* ata_eh_report() and related functions
* suspend/resume related functions
* ata_eh_recover() and related functions
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make reset methods and related functions deal with ata_link instead of
ata_port.
* ata_do_reset()
* ata_eh_reset()
* all prereset/reset/postreset methods and related functions
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make ata_eh_about_to_do() and ata_eh_done() deal with ata_link instead
of ata_port.
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make the following PHY-related functions to deal with ata_link instead
of ata_port.
* sata_print_link_status()
* sata_down_spd_limit()
* ata_set_sata_spd_limit() and friends
* sata_link_debounce/resume()
* sata_scr_valid/read/write/write_flush()
* ata_link_on/offline()
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Multiple links and different number of devices per link should be
considered to iterate over links and devices. This patch implements
and uses link and device iterators - ata_port_for_each_link() and
ata_link_for_each_dev() - and ata_link_max_devices().
This change makes a lot of functions iterate over only possible
devices instead of from dev 0 to dev ATA_MAX_DEVICES. All such
changes have been examined and nothing should be broken.
While at it, add a separating comment before device helpers to
distinguish them better from link helpers and others.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Introduce ata_link. It abstracts PHY and sits between ata_port and
ata_device. This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port. Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.
This patch only defines the host link. Multiple link handling will be
added later. Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* corruption fix: we only want the lower 16 bits of length (0 == 64kb)
* ditto: the upper layer sets max-phys-segments to LIBATA_MAX_PRD,
so we must reset it to own hw-specific length.
* delete unused mv_fill_sg() return value
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Three main sets of changes:
1) dmi_get_system_info() return value should have been marked const,
since callers should not be changing that data.
2) const-ify DMI internals, since DMI firmware tables should,
whenever possible, be marked const to ensure we never ever write to
that data area.
3) const-ify DMI API, to enable marking tables const where possible
in low-level drivers.
And if we're really lucky, this might enable some additional
optimizations on the part of the compiler.
The bulk of the changes are #2 and #3, which are interrelated. #1 could
have been a separate patch, but it was so small compared to the others,
it was easier to roll it into this changeset.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
The recent mv_fill_sg() rewrite, to fix a data corruption problem
related to IOMMU virtual merging, forgot to account for the
potentially-increased size of the scatter/gather table after its run.
Additionally, the DMA boundary is reduced from 0xffffffff to 0xffff
to more closely match the needs of mv_fill_sg().
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pata_marvell, use ioread* for iomap-ped memory
read* on pci_iomapped memory is incorrect, fix it
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix bug in sata_mv for cases where the IOMMU layer has merged SG entries
to larger than 64KB. They need to be split up before being sent to
the driver.
Just for simplicity's sake, split up at 64K boundary instead of 64K size,
since that's what the common code does anyway.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
There's a different version of DMI table for TECRA M3 where it has
proper vendor and product name entry. Add the entry to the broken
suspend list.
Angus Turnbull reported and provided initial patch.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Angus Turnbull <angus@twinhelix.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
sis_66_set_dmamode() also handles early UDMA100 (SIS630 ET) but is
missing udma timing value for UDMA100. According to sis5513, this
should be 0x8000. This caused UDMA100 device to fail on pata_sis till
it downgrades to UDMA66 while it works fine on sis5513 at UDMA100.
Reported by Adam Blech.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Adam Blech <desaster.area@addcom.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
When PCIX_IRQ_WOC is used, sil24 has an inherent race condition
between clearing IRQ pending and reading IRQ status. If IRQ pending
is cleared after reading IRQ status, there's possibility of lost IRQ.
If IRQ pending is cleared before reading IRQ status, spurious IRQs
will occur.
sata_sil24 till now cleared IRQ pending after reading IRQ status thus
losing IRQs on machines where PCIX_IRQ_WOC was used. Reverse the
order and ignore spurious IRQs if PCIX_IRQ_WOC.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ATI/AMD SB800 shares some device IDs with SB700,
and SB800 adds two more device IDs:0x4394,0x4395.
Signed-off-by: henry su <henry.su.ati@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Code moved to ioread/iowrite but the comment didn't
Also note a posting issue
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add Toshiba S1800-814 to whitelist for both pata_ali and alim15x3,
as it is correctly detected as 40-wire connected but this cable is
short enough to still use transfer modes higher than UDMA33.
Signed-off-by: Daniel Exner <dex@dragonslave.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
dev->horkage should be cleared over device hotunplug/plug. Clear it
in ata_dev_init().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix "lost" interrupt problem when using dma with CD/DVD drives in some
configurations. This problem can make installing linux from media
impossible for distro's that have switched to libata-only configurations.
The simple fix is to eliminate the use of dma for reading drive status, etc,
by checking the number of bytes to transferred.
This change will only affect the behavior of atapi devices, not disks.
There is more info at http://bugzilla.redhat.com/show_bug.cgi?id=242229
This patch is for 2.6.22.1
Signed-off-by: Jeff Norden <jnorden@math.tntech.edu>
Reviewed-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
I think that I've found and fixed the problem. There is a copy/paste bug in
vt6421_set_dma_mode() function which causes wrong values to be written to
PATA_UDMA_TIMING register.
This patch fixes a copy/paste bug that breaks DMA modes on VT6421 PATA port.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some notebooks need bit18 of IOCFG to be cleared for the drive bay to
work even though the bit is NOOP according to the datasheet. This
patch implement IOCFG bit18 quirk and apply it to Clevo M570U.
http://bugzilla.kernel.org/show_bug.cgi?id=8051
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: D. Angelis <dangelis@beta-cae.gr>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some drives choke on READ_NATIVE_MAX_ADDRESS[_EXT]. Implement
ATA_HORKAGE_BROKEN_HPA and apply it to affected drives.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch corrects sata_promise to classify FastTrack TX4200
(DID 3515/3519) as a second-generation chip. Promise's partial-
source FT TX4200 driver confirms this classification.
Treating it as a first-generation chip causes several problems:
1. Detection failures. This is a recent regression triggered by
the hotplug-enabling changes in 2.6.23-rc1.
2. Various "failed to resume link for reset" warnings.
This patch fixes <http://bugzilla.kernel.org/show_bug.cgi?id=8936>.
Thanks to Stephen Ziemba for reporting the bug and for testing the fix.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: Stephen Ziemba <sziemba@ecn.purdue.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Satellite U200 also shares the problem. Add it to the broken suspend
list. Original patch from John Schember.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: John Schember <john@nachtimwald.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Resend trying to remove 8-bit characters in the email.
This patch adds the Intel Tolapai IDE mode SATA controller DID's.
Signed-off-by: Jason Gaston <jason.d.gaston@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
On some early drives (pre ATA1) this feature is not supported. If it
fails then we know the drive geometry is the hardware geometry and the
one we tried to set anyway so just carry on.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
libata: don't check n_sectors during revalidation if zero
pata_via: Add Arima W730-K8 and other rebadgings
pata_sis: Add the FSC Amilo and friends
pata_pdc2027x: PLL detection fixes
libata: fix n_sectors failure handling during revalidation
Whoever did the PCI revision patch slipped up on the it821x, and I
didn't spot this at the time either. They moved the check for the
errata from the 0x10 revision to 0x11. Put it back
This one is important for 2.6.23 final as in some cases bad things will
occur if 0x10 revision boards don't get the fixups.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the initial configuration fails early, n_sectors is left at zero.
Checking against it during revalidation makes retried configuration
fail due to n_sectors mismatch. Ignore zero n_sectors during
revalidation.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
More cable funnies
Signed-off-by: Alan Cox <alan@redhat.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Previously I reported that the pata_pdc2027x PLL detection changes
in kernel 2.6.22 broke the driver on my PowerMac:
>pata_pdc2027x: Invalid PLL input clock 1691742kHz, give up!
This is followed by a number of errors and speed reduction
steps on the affected ports.
There are two bugs in pata_pdc2027x's PLL detection code:
1. The PLL counter's start value is read before the chip is
put in "test mode". Outside of test mode the counter is
halted, and on the PowerMac the counter is zero because
the chip hasn't been initialised by its BIOS.
The fix is to move the read of the start value to after
test mode is started, but before the mdelay() in test mode.
This also improves the precision of the PLL detection.
2. The code to compute the number of PLL decrements during the
mdelay() in test mode fails to consider that the PLL counter
only is 30 bits wide. If there is a wraparound, it will compute
an incorrect and much too large value. On the PowerMac, the
start count is zero, the end count is a large 30-bit value, so
wraparound occurs and an out of bounds PLL clock is detected.
The fix is to mask the (start - end) computation to 30 bits.
While debugging this I also noticed that pdc_read_counter()
reads the two halves of the 30-bit PLL counter as 16-bit values,
and then combines them as if the halves only are 15 bits wide.
To avoid confusion, the halves should be read as 15-bit values.
This patch implements all three changes. It fixes the PLL detection
failure on my PowerMac, and doesn't cause any regressions on an x86
with an identical card.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
If revalidation fails because device has different n_sectors after
configuration the original n_sectors should be restored before failing
revalidation. Without this fix, n_sectors difference will incorrectly
and silently pass revalidation when revalidation is retried.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Adjust libata to ignore errors after spinup
This patch is to ignore errors from the spinup attempt if the drive is
in the "standby id" state.
Signed-off-by: Ryan Power <rpower@sysreset.com>
Acked-by: Mark Lord <liml@rtr.ca>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add TECRA M7 to broken suspend list. Reported by Marie Koreen.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Marie Koreen <kbug@koreen.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix several inconsistencies in these drivers WRT reporting the clocks:
- when using DPLL mode, 'pata_hpt37x' driver reported the DPLL frequency as the
PCI clock -- make it properly report both clocks and add the same ability to
the 'pata_hpt3x2n' driver;
- both drivers sometimes use "pata_hpt3*:" and sometimes "hpt3*:" in the
messages -- make them use only the former one;
- the message about failed DPLL stablizatios deserves KERN_ERR and a bang. :-)
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The DPLL tuning code always set up it for 66 MHz due to wrong UltraDMA mask
including mode 5 used to check for the necessity of 66 MHz clocking -- this
caused 66 MHz clock to be used for HPT374 chip that does not tolerate it.
While fixing this, also remove PLL mode from the TODO list -- I don't think
it's still a relevant item.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Maximum supported UDMA mode for AEC6280[R] is UDMA5 (not UDMA4)
and for AEC6880[R] it is UDMA6 (not UDMA5):
* Fix the problem by adding missing struct ata_port_info to artop_init_one().
* Use the right naming (s/626/628/).
* Bump driver version.
Fixes IDE->libata regression, problem was never present in IDE aec62xx driver.
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Underneath all the HPT packaging, PCI identifiers, binary driver modules
and stuff you find that ...
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Alan Cox suggested that the solution to the FIXMEs in pata_icside is
to use a private postreset method to detect the lack of devices on a
port, and in such a case, disable the interrupt for the port.
This patch implements such a method, and removes the hard coded
disable of port 0. Tested as working.
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Fix MWDMA timings setup in sis_old_set_dmamode() and sis_66_set_dmamode().
The old timings were overclocked (even worse behavior than sis5513 IDE driver
which depends on BIOS to program correct timings), the new timings are taken
from the datasheet (they match timings from ATA spec).
* Fix UDMA timings setup in sis_old_set_dmamode().
Misplaced pci_write_config_word() call resulted in UDMA timings never
being set.
* Fix comments for sis_133_early_set_dmamode() and sis_133_set_dmamode():
- only the former function handles early SiS 961 bridges
- both functions lack MWDMA timings setup
* Fix typos in sis_100_set_piomode() and sis_133_set_piomode() comments.
* Bump driver version.
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add Tecra M3 to the broken suspend blacklist. Tecra M3 doesn't have
proper DMI_PRODUCT_NAME but has an OEM_STRING instead. Match it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out broken suspend blacklist matching into
piix_broken_suspend().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Seems nobody else is checking/testing this case as it keeps getting
horked.
If we have no BAR4 mapping on an SFF controller this is *NOT* an error,
it just means it isn't doing BMDMA.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Just one version of Linux ago
The PLL code broke - oh no!
But set the right mode
And fix up the code
Makes the PLL timing sync go
[whatever happened to the sailor from Nantucket, hero of many limericks? -jg]
Closes-bug: #8791
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ACPI implementations in several TOSHIBA laptops are weird and burn cpu
cycles for tens of seconds while trying to suspend if the PCI device
for the ATA controller is disabled when the ACPI suspend is called.
This patch uses DMI to match those machines and bypass device disable
on those machines during suspend. As the device needs to be put into
enabled state on resume without affecting PCI enable count, matching
resume callback uses __pci_reenable_device().
This bug is reported in bugzilla bug 7780.
http://bugzilla.kernel.org/show_bug.cgi?id=7780
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
In most cases, when EH is scheduled, all in-flight commands are
aborted causing EH to kick in immediately. However, in some cases
(especially with PMP), it's unclear which commands are affected by the
error condition and although aborting all in-flight commands work, it
isn't optimal and may cause unnecessary disruption. On the other
hand, waiting for in-flight commands to drain themselves can take up
to 30seconds.
This patch implements EH fast drain to handle such situations. It
gives in-flight commands some time to finish up but doesn't wait for
too long. After EH is scheduled, fast drain timer is started and if
no other completion occurs in ATA_EH_FASTDRAIN_INTERVAL all in-flight
commands are aborted. If any completion occurred in the interval, the
port is given another interval to finish up itself.
Currently ATA_EH_FASTDRAIN_INTERVAL is 3 secs which should be enough
for finishing up most commands.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
If SError isn't accessible, EH can't tell whether hotplug has happened
or not. Report SError read failure with AC_ERR_OTHER and schedule
probing with hardreset. This will be mainly useful for PMPs.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ATA_EHI_HOTPLUGGED is a hint for reset functions indicating the the
port might have gone through hotplug/unplug just before entering EH.
Reset functions modify their behaviors a bit to handle the situation
better - e.g. using longer debouncing delay.
Currently, once HOTPLUG is set, it isn't cleared till the end of EH.
This is unnecessary and makes EH take longer. Clear the HOTPLUGGED
flag after a reset try (successful or not).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
SCSI scan may fail due to memory allocation failure even if EH is not
in progress. Due to use of GFP_ATOMIC in SCSI scan path, allocation
failure isn't too rare especially while probing multiple devices at
once which is the case when a bunch of devices are connected to PMP.
This patch moves SCSI scan failure detetion logic from
ata_scsi_hotplug() to ata_scsi_scan_host() and implement synchronous
scan behavior. The synchronous path sleeps briefly and repeats SCSI
scan if some devices aren't attached properly. It contains robust
retry loop to minimize the chance of device misdetection during boot
and falls back to async retry if everything fails.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Debouncing failure is a good indicator of basic link problem. Use
-EPIPE to indicate debouncing failure and make ata_eh_reset() invoke
sata_down_spd_limit() if the error occurs during reset.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
sata_down_spd_limit() first reads the current SPD from SStatus and
limit the speed to the lower one of one below the current limit or one
below the current SPD in SStatus. SPD may not be accessible or valid
when SPD down is requested making sata_down_spd_limit() fail when it's
most needed.
This patch makes the current SPD cached after each successful reset
and forces GEN I speed (1.5Gbps) if neither of SStatus or the cached
value is valid, so sata_down_spd_limit() is now guaranteed to lower
the speed limit if lower speed is available.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
the onchip SATA type set in the system BIOS:
Device Device ID
SATA in IDE mode 0x4390
SATA in AHCI mode 0x4391
SATA in non-raid5 driver 0x4392
SATA in raid5 driver 0x4393
Although the device ID is different, they use the same AHCI driver
.The attached file is the patch for adding these device
IDs for ATI SB700.
Signed-off-by: henry.su.ati@gmail.com
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make ahci_scr_read/write() handle SCR_NOTIFICATION if the controller
supports it. Also, print "sntf" in the cap line if supported.
While at it, convert eight space into a tab in ahci_print_info().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ahci_save_initial_config() is responsible for reading, screening the
host CAP register and storing the modified result into hpriv->cap for
the rest of the driver. Move ATA_FLAG_NO_NCQ handling into
ahci_save_initial_config(). It's more consistent this way and the
rest of the driver can always refer to hpriv->cap to determine
configured capability.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Convert ->scr_read/write callbacks to return error code to better
indicate failure. This will help handling of SCR_NOTIFICATION.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
When an NCQ command fails, all commands in flight are aborted and the
offending one is reported using log page 10h. Depending on controller
characteristics and LLD implementation, all commands may appear as
having a device error due to shared TF status making it hard to
determine what's actually going on.
This patch adds AC_ERR_NCQ, marks the command reported by log page 10h
with it and print extra "<F>" after the error report for the command
to help distinguishing the offending command.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Requiring LLDs to format multiple error description messages properly
doesn't work too well. Help LLDs a bit by making ata_ehi_push_desc()
insert ", " on each invocation. __ata_ehi_push_desc() is the raw
version without the automatic separator.
While at it, make ehi_desc interface proper functions instead of
macros.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out sil24_do_softreset() which takes @pmp as its last
argument. This will be used to implement sil24_pmp_softreset().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out sil24_exec_polled_cmd() from sil24_softreset(). This
will be used to implement sil24_pmp_read/write().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Replace sil24_update_tf() to sil24_read_tf() which reads TF into
passed int result TF argument and can read TFs of PMP links. This
will be used by PMP support.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out ahci_do_softreset() which takes @pmp as its last
argument. This will be used to implement ahci_pmp_softreset().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out ahci_exec_polled_cmd() from ahci_softreset(). This will
be used to implement ahci_pmp_read/write(). ahci_exec_polled_cmd()
performs reset_engine before returning if the command fails (times
out). This is to improve robustness.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out stop_engine - CLO - start_engine sequence from
ahci_softreset() and ahci_clo() into ahci_reset_engine() and use it in
ahci_softreset() and ahci_post_internal_cmd(). The function will also
be used to prepare for and clean up after PMP register access
commands.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Use deadline instead of fixed timeout for 1st FIS for SRST to improve
robustness of SRST.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add @is_cmd to ata_tf_to_fis(). This controls bit 7 of the second
byte which tells the device whether this H2D FIS is for a command or
not. This cleans up ahci a bit and will be used by PMP.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_tf_read was setting HOB bit when lba48 command was submitted, but
was not clearing it before reading "normal" data. As it is only place
which sets HOB bit in control register, and register reads should not
be affected by other bits, let's just clear it when we are done with
reading upper bytes so non-48bit commands do not have to touch ctl
at all.
pata_scc suffered from same problem...
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch fixes some issues of the previous patch:
- Use mode_filter() hook to limit ATAPI UDMA mode
- "data loss" warning message
- handling of udma_mask
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Commit df69c9c543 moved only prototype of
out of CONFIG_PM. Move function out as well. Box seems to boot fine.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Yay, the first one from Seagate. 3.ALC firmware is okay. This was
reported by Sam Freed on bugzilla bug 8759.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Sam Freed <sam@freed.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
pata_platform: Fix NULL pointer dereference
pata_platform currently dereferences a NULL pointer in pata_platform_probe()
if pdev->dev.platform_data is set to NULL. This breakage was most likely
introduced by commit 5f45bc5097.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* trim trailing whitespace
* document some flags, registers, and register bits
* fix locking around EDMA on/off and configuration
* continue replacing "constant OP var" with "var OP constant"
* use new pci_try_set_mwi()
Signed-off-by: Jeff Garzik <jeff@garzik.org>
One card submitted by user.
Signed-off-by: Marcin Juszkiewicz <openembedded@hrw.one.pl>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (34 commits)
PCI: Only build PCI syscalls on architectures that want them
PCI: limit pci_get_bus_and_slot to domain 0
PCI: hotplug: acpiphp: avoid acpiphp "cannot get bridge info" PCI hotplug failure
PCI: hotplug: acpiphp: remove hot plug parameter write to PCI host bridge
PCI: hotplug: acpiphp: fix slot poweroff problem on systems without _PS3
PCI: hotplug: pciehp: wait for 1 second after power off slot
PCI: pci_set_power_state(): check for PM capabilities earlier
PCI: cpci_hotplug: Convert to use the kthread API
PCI: add pci_try_set_mwi
PCI: pcie: remove SPIN_LOCK_UNLOCKED
PCI: ROUND_UP macro cleanup in drivers/pci
PCI: remove pci_dac_dma_... APIs
PCI: pci-x-pci-express-read-control-interfaces cleanups
PCI: Fix typo in include/linux/pci.h
PCI: pci_ids, remove double or more empty lines
PCI: pci_ids, add atheros and 3com_2 vendors
PCI: pci_ids, reorder some entries
PCI: i386: traps, change VENDOR to DEVICE
PCI: ATM: lanai, change VENDOR to DEVICE
PCI: Change all drivers to use pci_device->revision
...
It seems irq_on() in ata_bus_reset() and ata_std_postreset()
are leftover of the EDD reset. Remove them.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The last two slots of MAP 00b of ich6m was incorrectly marked as
reserved. This is left over from converting the entry to allow 00b.
This causes no real problem. It only makes the driver print annoying
warning message. Fix it.
[patch also proferred by Pierre Tardy at the end of 2006 -jg]
Signed-off-by: Tejun Heo <htejun@gmail.com>
--
drivers/ata/ata_piix.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add another Maxtor 6B200M0 drive with broken NCQ to the list.
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Due to a mistake in test logic, Gen-IIE chips were being treated as
Gen-II chips in some cases. Fix this, and in the process, clean up
IS_50XX/IS_60XX tests to the more uniform IS_GEN_{I,II,IIE} tests.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Continue replacing "CONSTANT & var" tests with "var & CONSTANT"
* Don't clear EDMA_CFG_NCQ_GO_ON_ERR on Gen-IIE, where that bit does
not exist
* Set I/O Id field in descriptor, where present. Appears to work
fine on all versions, even though queueing is still disabled.
* call pci_set_mwi(), to (a) make sure cacheline size is set properly,
and (b) enable MWI transactions
* Remove never-used handling of coalescing interrupt bits (these events
are always masked)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
As suggested by Andrew, add pci_try_set_mwi(), which does not require
return-value checking.
- add pci_try_set_mwi() without __must_check
- make it return 0 on success, errno if the "try" failed or error
- review callers
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Instead of all drivers reading pci config space to get the revision
ID, they can now use the pci_device->revision member.
This exposes some issues where drivers where reading a word or a dword
for the revision number, and adding useless error-handling around the
read. Some drivers even just read it for no purpose of all.
In devices where the revision ID is being copied over and used in what
appears to be the equivalent of hotpath, I have left the copy code
and the cached copy as not to influence the driver's performance.
Compile tested with make all{yes,mod}config on x86_64 and i386.
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Acked-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Minor cleanups, new definitions, and code movement, preparing for
upcoming new-EH and NCQ changes. This commit shoult not change behavior
at all.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out ata_eh_handle_dev_fail() from ata_eh_recover(). This is
in preparation of ata_link and PMP support.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add Hitachi HDS7250SASUN500G 0621KTAWSD to list of devices with broken NCQ.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Workaround for errata A308: turn down the UDMA mode and retry
the DMA command when the data lost condition is detected.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Please warmly welcome the first member from FUJITSU to the prestigious
NCQ spurious completion club.
This is reported by Serge Van Thillo in bugzilla bug 8730.
http://bugzilla.kernel.org/show_bug.cgi?id=8730
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Serge van Thillo <nulleke@hotmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The HPT343/345 (aka 363) is a bit of a warped device. For many setups you
need to access the other registers via BAR4 offsets. PIO is now rock
solid, DMA isn't. Unfortunately the drivers/ide hpt34x driver is
completely broken so doesn't help further debug.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Horkage handling had the following problems.
* dev->horkage was positioned after ATA_DEVICE_CLEAR_OFFSET, so it was
cleared before the device is configured. This broke
HORKAGE_DIAGNOSTIC.
* Some used dev->horkage while others called ata_device_blacklisted()
directly. This was at best confusing.
This patch moves dev->horkage right after dev->flags and set the field
according to the blacklist during device configuration. All users
test against dev->horkage. ata_device_blacklisted() now has only one
user, make it static. While at it, rename it to ata_dev_blacklisted()
for consistency.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The Zip 250 which chokes on MWDMA SET_XFERMODE sometimes have "Floppy"
appeneded to its model number. Quirk it too.
http://bugzilla.kernel.org/show_bug.cgi?id=8563
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Hans de Bruin <bruinjm@xs4all.nl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
With PCI resource fix up for legacy hosts. We can use the same code
path to allocate IO resources and initialize host for both legacy and
native SFF hosts. Only IRQ requesting needs to be different.
Rename ata_pci_*_native_host() to ata_pci_*_sff_host(), kill all
legacy specific functions and use the renamed functions instead. This
simplifies code a lot.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement suspend and resume routines for mpc52xx ata driver.
Tested on Lite5200b with deep-sleep and low-power (not yet in-tree)
modes.
Signed-off-by: Domen Puncer <domen.puncer@telargo.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch enables hotplugging of SATA devices in the
sata_promise driver. It's been tested successfully on
both first- and second-generation Promise SATA chips:
SATA150 TX2plus, SATAII150 TX2plus, SATAII150 TX4,
SATA300 TX2plus, and SATA300 TX4.
The only quirk I've seen is that hotplugging (insertion)
on the first-generation SATA150 TX2plus requires a lengthier
EH sequence than on the second-generation chips.
On the second-generation chips a simple soft reset seems
to suffice, but on the first-generation chip there's a
"port is slow to respond" after the initial soft reset,
after which libata issues a hard reset, and then the
device is recognised.
The hotplug checks are high up in the interrupt handling
path, not deep down in error_intr as in ahci/sata_sil24.
That's because the chip doesn't signal hotplug status changes
in the per-port status register: instead a global register
contains hotplug control and status flags for all ports.
I considered following the ahci/sata_sil24 structure, but
that would have required non-trivial changes to the interrupt
handling path, so I chose to keep the hotplug changes simple
and unobtrusive.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
--
This patch depends on the "sata_promise: cleanups" patch.
Changes since the previous version (posted June 19):
- Correct pdc_interrupt() to increment 'handled' also in
the hotplug case. This prevents IRQ_NONE from being
returned when an interrupt only has hotplug events to
handle, which could confuse the kernel's IRQ machinery.
- Added testing on the SATAII150 TX4.
drivers/ata/sata_promise.c | 41 ++++++++++++++++++++++++++++++++++++-----
1 files changed, 36 insertions(+), 5 deletions(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
If you are using a SiS controller and the BIOS didn't set it up then the
FIFO may be left active when we try and set up the CD. Not convinced this
matters but I'd prefer to be safe
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
We should not use cancel_work_sync(delayed_work->work). This works, but not
good. We can use cancel_rearming_delayed_work(), this also simplifies the
code.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Indicate whether this is a Generation-I (50xx), Generation-II (60xx),
or Generation-II-E (6042/7042) chip.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The ATA_UDMAx masks are self-documenting, and far better than manually
writing in the hex mask.
Note that pata_it8213 mask differed from the comment. Added a FIXME there.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add support for the SATA portion of Marvell's AHCI-compatible chips.
The PATA port capability, also available via AHCI, is disabled until
support is completed.
NCQ and PCI MSI are disabled by default. Marvell says "we use NCQ" in
their drivers but "we do not use PCI MSI." Theoretically that implies
we need to fix ahci.c to work with Marvell NCQ, but one wonders why
Marvell NCQ is any different from other AHCI chips.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Use ATA_UDMA*
* Remove FIXME notations that once served to remind us to verify
that these were indeed the correct UDMA masks. They are.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add ata_dumb_qc_prep and supporting logic so that a driver can just
specify it needs to be helped in this area. 64K entries are split
as with drivers/ide.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
sil24_interrupt() loads host->ports[i] into a local variable,
validates it, and then loads the value again in the call to
sil24_host_intr(). This patch replaces the second load by a
reference to the local variable.
This is safe since no side-effects have occurred since the
initial load. It also improves readability since it makes
it clear that the parameter to sil24_host_intr() is the same
value which was just validated.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
On some embedded platforms, such as blackfin, the gpio interrupt for
IDE interface is designed to be triggered with high voltage. The gpio
port should be configured properly by set_irq_type() when register
the irq. This patch enable the generic pata platform driver to
accept platform irq flags data.
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch applies some trivial cleanups to sata_promise:
- repair whitespace damage
- correct comment at board_2057x_pata definition
- pull SATAII TX4 support code out to separate functions
- rename ata_nr to ata_no for consistency with libata's port_no
- remove some init-time debug printks (requested by Jeff)
This patch should cause no behavioural changes, except for
the removed printks.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
--
drivers/ata/sata_promise.c | 56 ++++++++++++++++++---------------------------
1 files changed, 23 insertions(+), 33 deletions(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix various bugs in pio/mwdma mode programming.
* Control bits in the timing register wasn't cleared properly while
programming PIO mode.
* MWDMA mode programming cleared the wrong part of control bits.
* MWDMA mode programming cleared udma_mask even when the controller
doesn't support UDMA.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Art Haas <ahaas@airmail.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
sata_sx4:
- describe overall driver theory of operation
- add a few constants that will be used in the future
sata_via:
- remove mention of an old-EH function that is going away
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* convert tabs to spaces
* convert some hex numbers to (1 << n) preferred format
* document i2c and timer control register bits
Signed-off-by: Jeff Garzik <jeff@garzik.org>