Clean up the codebase, no functional changes.
- merge the au1xmmc.h header contents into the driver file,
- indentation, spelling and style fixes.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Wire up the SD controllers' SDIO IRQ capability.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Remove the DB1200 board-specific functions (card present, read-only,
activity LED methods) and instead add platform data which is passed
to the driver. This also allows for platforms to implement other
carddetect schemes (e.g. dedicated irq) without having to pollute the
driver code. The poll timer (used for pb1200) is kept for compatibility.
With the board-specific stuff gone, the driver's ->probe() code can be
cleaned up considerably.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The byte mode support fails to clear the byte mode bit in the command
register, possibly leaving byte mode enabled with the counters programmed
in non-byte mode.
Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
According to the documentation the AT91SAM9261 MCI shares the block size
limitations of the AT91RM9200 MCI. Also the errata documentation for
AT91RM9200 and AT91SAM9261 state that stream commands are not supported.
This has not been tested on actual hardware.
Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
AT91SAM926[0/3] PDC must write at least 12 bytes. The code compiles and runs
but the actual condition for this erratum did not trigger in my tests so it's
unclear if it actually works as intended.
Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
In at91_mci_completed_command() function, this patch distinguishes
command error and data error. It reports it in the corresponding
error field.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Reading AT91_MCI_SR again at the end of transfer can corrupt the
error reporting. Some fields in the SR register are read-and-clear.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Enable SDIO interrupt handling.
Signed-off-by: Eric Benard <ebenard@free.fr>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
at91_mci is capable of multiwrite. Enable it before it disappears.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Modify bytes_xfered value after a write.
That will report, as accurately as possible, the amount of
sectors that are effectively written.
This update introduces the check of the busy signal given by
the card.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The at91 mci controller internal state machine seems to often crash. This can
be fixed by resetting the controller after each command for at91rm9200 and by
setting the MCI_BLKR register on at91sam926*.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Hans J Koch <hjk@linutronix.de>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Implement transfer with size not modulo 4 for at91sam9*. Please note that the
at91rm9200 simply can't handle this.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Now get_ro() callback must return 0/1 values for its logical states, and
negative errno values in case of error. If particular host instance doesn't
support RO/WP switch, it should return -ENOSYS.
This patch changes some hosts in two ways:
1. Now functions should be smart to not return negative values in
"RO asserted" case (particularly gpio_ calls could return negative
values for the outermost GPIOs).
Also, board code usually passes get_ro() callbacks that directly return
gpioreg & bit result, so at91_mci, imxmmc, pxamci and mmc_spi's get_ro()
handlers need take special care when returning platform's values to the
mmc core.
2. In case of host instance didn't implement get_ro() callback, it should
really return -ENOSYS and let the mmc core decide what to do about it
(mmc core thinks the same way as the hosts, so it isn't functional
change).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch adds new platform data variable "caps", so platforms
could pass theirs capabilities into MMC core (for example, platforms
without interrupt on the CD line will most probably want to pass
MMC_CAP_NEEDS_POLL).
New platform get_cd() callback provided to optimize polling.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Gracefully handle when the device is suddenly removed. Do a test read
and avoid any further access if that read returns -1.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
JMicron chips sometimes have two interfaces to work around limitations
in Microsoft's sdhci driver. This patch allows us to use either interface.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some of the JMicron chips requires us to manually enable the power
output stages of the chip. Add the necessary hooks and functions to
manage this.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Give the quirk for broken timeout handling a better chance of handling
more controllers by simply classifying the system as broken and setting
a fixed value.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Remove the quirk to force DMA on the Ricoh and TI controllers as it is
no longer needed. The only bug they have is that they use an incorrect
PCI interface value, and that is not respected anymore.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The SDHCI interface is not PCI specific, yet the Linux driver was
intimitely connected to the PCI bus. This patch properly separates
the PCI specific portion from the bus independent code.
This patch is based on work by Ben Dooks but he did not have time
to complete it.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The specification is insufficiently strict when it comes to how the
hardware should update the block count register, making it useless
for checking transfer progress.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (241 commits)
[ARM] 5171/1: ep93xx: fix compilation of modules using clocks
[ARM] 5133/2: at91sam9g20 defconfig file
[ARM] 5130/4: Support for the at91sam9g20
[ARM] 5160/1: IOP3XX: gpio/gpiolib support
[ARM] at91: Fix NAND FLASH timings for at91sam9x evaluation kits.
[ARM] 5084/1: zylonite: Register AC97 device
[ARM] 5085/2: PXA: Move AC97 over to the new central device declaration model
[ARM] 5120/1: pxa: correct platform driver names for PXA25x and PXA27x UDC drivers
[ARM] 5147/1: pxaficp_ir: drop pxa_gpio_mode calls, as pin setting
[ARM] 5145/1: PXA2xx: provide api to control IrDA pins state
[ARM] 5144/1: pxaficp_ir: cleanup includes
[ARM] pxa: remove pxa_set_cken()
[ARM] pxa: allow clk aliases
[ARM] Feroceon: don't disable BPU on boot
[ARM] Orion: LED support for HP mv2120
[ARM] Orion: add RD88F5181L-FXO support
[ARM] Orion: add RD88F5181L-GE support
[ARM] Orion: add Netgear WNR854T support
[ARM] s3c2410_defconfig: update for current build
[ARM] Acer n30: Minor style and indentation fixes.
...
The pxa27x DMA controller defaults to 64-bit alignment. This caused
the SCR reads to fail (and, depending on card type, error out) when
card->raw_scr was not aligned on a 8-byte boundary.
For performance reasons all scatter-gather addresses passed to
pxamci_request should be aligned on 8-byte boundaries, but if
this can't be guaranteed, byte aligned DMA transfers in the
have to be enabled in the controller to get correct behaviour.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Even the newer ENE controllers have bugs in their DMA engine that make
it too dangerous to use. Disable it until someone has figured out under
which conditions it corrupts data.
This has caused problems at least once, and can be found as bug report
10925 in the kernel bugzilla.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The CaFe chip has a hardware bug that ends up with us getting a timeout
value that's too small, causing the following sorts of problems:
[ 60.525138] mmcblk0: error -110 transferring data
[ 60.531477] end_request: I/O error, dev mmcblk0, sector 1484353
[ 60.533371] Buffer I/O error on device mmcblk0p2, logical block 181632
[ 60.533371] lost page write due to I/O error on mmcblk0p2
Presumably this is an off-by-one error in the hardware. Incrementing
the timeout count value that we stuff into the TIMEOUT_CONTROL register
gets us a value that works. This bug was originally discovered by
Pierre Ossman, I believe.
[thanks to Robert Millan for proving that this was still a problem]
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This has been sitting around unloved for way too long..
The Marvell CaFe chip's SD implementation chokes during card insertion
if one attempts to set the voltage and power up in the same
SDHCI_POWER_CONTROL register write. This adds a quirk that does
that particular dance in two steps.
It also adds an entry to pci_ids.h for the CaFe chip's SD device.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
imx_dma_request_by_prio can return channel number by itself.
No need to supply variable address through parameters.
Also converted all drivers using this function.
Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With CONFIG_DEBUG_SHIRQ set we will get an interrupt as soon as we
allocate one. Tasklets may be scheduled in the interrupt handler but they
will be initialized after the handler returns, causing a BUG() in
kernel/softirq.c when they run.
Should fix this Fedora bug report:
https://bugzilla.redhat.com/show_bug.cgi?id=449817
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
at91_mci: minor cleanup
mmc: mmc host test driver
mmc: Fix omap compile by replacing dev_name with dma_dev_name
MMC_POWER_ON is a noop, no need to set the power pin again.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch fixes error:
drivers/mmc/host/omap.c: In function 'mmc_omap_get_dma_channel':
drivers/mmc/host/omap.c:1038: error: called object 'dev_name' is not a function
Commit 06916639e2 adds a function
called dev_name. This will cause a name conflict as dev_dbg calls
dev_name(((host->mmc)->parent)).
This same issue should not affect other drivers as they don't seem
to use dev_name with dev_dbg.
Thanks to Paul Walmsley <paul@pwsan.com> for figuring this one out.
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Otherwise it can only take the values 0/-1 which doesn't seem to
have been intended.
drivers/mmc/host/sdhci.h:190:20: error: dubious one-bit signed bitfield
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes some two minor clk issues.
The first is a comparison where a byte will probably wrap around to 0 instead of being saturated to 255, shouldn't be triggered very often but need fixing.
The second is an attempt by the driver to adjust MCLK down to the maximum frequency according to the spec, so we don't accidentally overclock the PL18x block. None of the mach-{versatile|integrator|lh7a40x} that use it in-tree seem to have a problem with this (all are well below 100MHz, typically 33MHz), but some day there will be a problem.
This is not applied on top of the earlier mmci patch for race condition but rather a clean 2.6.25, but I guess it applies without major protests anyway.
Signed-off-by: Linus Walleij <triad@df.lth.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Tony Jones <tonyj@suse.de>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Updated version of 4446/1. This also drops the suggested comparison
of host_remain for == 0, since that doesn't make sense (still works
for us, too). We have verified that this patch solve race problems
on atleast 2 archs at high frequencies.
(Verbatim copy of old patch text below.)
The patch below fixes a race condition in the ARM MMCI PL18x driver.
If new data arrives in the FIFO while existing data is being read then
we get a second iteration of the loop in mmci_pio_read.
However host->size is not updated until after mmci_pio_read returns,
so we get count = number of new bytes PLUS number of bytes already
copied in the first iteration. This results in a FIFO underrun as
we try and read mode data than is available.
The fix is to compensating for data read on previous iterations
when calculating the amount of data in the FIFO.
Signed-off-by: Linus Walleij <triad@df.lth.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The quirk was meant to just inhibit some resets, but ended up blocking
all of them. Fortunately, this was just what was needed. Change the
comment to reflect reality.
Also, this issue has just been observed on Samsung laptops, so reduce
the number of chips the quirk affects.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The limit was a fixed 100k limit in the busy loop, which is not
accurate. It would better to have time limit for the worst case
which occurs when sending 80 cycles at 400 kHz and takes about
200 microseconds, so limit the max time spend in the busy loop
for some 250 microseconds.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Use work queues for starting new commands instead of starting them
directly from irq handler. The command scheduling needs to be delayed
a bit for some cards which should not be done from an interrupt.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
MMCA spec says the mmc clock should be kept running for at least
8 cycles after the last RW request. Ensure this with lazy clock
disable after a request, or with an explicit delay before
switching a slot.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Abort failed command from workqueue rather than from an interrupt,
allowing longer delays in abortion.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The cover waitqueue is occasionally scheduled twice from timer
and the interrupt and oops follows. It would have been possible
to fix this problem with spinlocks but using tasklet was a dropin
solution with no need for locking.
This path also adds some cleanups.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
If the get_cover_state is not set, it occurs the oops.
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Using setup_timer() instead of init_timer() on omap.c file.
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
When a card is removed while it is being accessed, a command can get stuck so
that no timeout or end of command interrupt ever occurs. The command getting
stuck is almost always CDM12, but also the other commands can get stuck. Catch
a stuck command with a timer and try sending the initialization stream until
the controller starts running again and responds with the end of command
status.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
General code cleanup, modifications at some dev_* functions and
other hacks at mmc_omap_irq() for MMC multislot support.
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Modifications at power functions to MMC multislot support. This patch
also move board-specific code out of MMC OMAP driver.
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Fix the data timeout calculation for MMC multislot support.
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
New functions to support MMC multislot:
mmc_omap_release_dma() and mmc_omap_abort_xfer().
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch adds back MMC cover switch support in a way that
supports multiple slots.
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Introduce new MMC multislot structure and change driver to use it.
Note that MMC clocking is now enabled in mmc_omap_select_slot()
and disabled in mmc_omap_release_slot().
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch removes the MMC cover switch handling temporarily
to make following multislot patches cleaner.
MMC cover switch handling will be added back in later patches
after adding basic multislot support.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
According with commit 255d01af9a
from Linux-OMAP tree, the BYTEBLOCK capability was removed by Pierre Ossman.
MMC_CAP_BYTEBLOCK is not defined causing the compile error:
drivers/mmc/host/omap.c: In function `mmc_omap_probe':
drivers/mmc/host/omap.c:1077: error: `MMC_CAP_BYTEBLOCK' undeclared (first use in this function)
drivers/mmc/host/omap.c:1077: error: (Each undeclared identifier is reported only once
drivers/mmc/host/omap.c:1077: error: for each function it appears in.)
Signed-off-by: Francisco Alecrim <francisco.alecrim@indt.org.br>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
As noted by Kyungmin Park, the divisor calculation has
an unnecessary increase.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch removes some opcodes from host driver so there's no need on putting
'#include <linux/mmc/mmc.h>', that should not be needed in host drivers.
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Hook up the controller LED to the LED subsystem, allowing more flexible
control than simply indicating an ongoing request.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Since 43cc71eed1, the platform modalias is
prefixed with "platform:". Add MODULE_ALIAS() to the hotpluggable MMC host
platform drivers, to re-enable auto loading.
Also, add missing owner declarations in driver init.
[dbrownell@users.sourceforge.net: registration fixes]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds support for the Ricoh RL5c476 chip: with this
the mmc adapter that needs this disabler (R5C843) can also be
handled correctly when it sits on a RL5c476.
Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Update the AT91 MMC driver to use the generic GPIO calls instead of the
AT91-specific calls; and to request (and release) those GPIO signals.
That required updating the probe() fault cleanup codepaths. Now there
is a single sequence for freeing resources, in reverse order of their
allocation. Also that code uses use dev_*() for messaging, and has less
abuse of KERN_ERR.
Likewise with updating remove() cleanup. This had to free the GPIOs,
and while adding that code I noticed and fixed two other problems: it
was poking at a workqueue owned by the mmc core; and in one (rare)
case would try freeing an IRQ that it didn't allocate.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some devices have several controllers; need add the index info to
device slot name host->slot_desc[]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Both of these drivers work well (although some hardware still has
its problems) and are not in the "alpha" quality that EXPERIMENTAL
suggests.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
As pci config space is reinitialised on a suspend/resume cycle, the
disabler needs to work its magic at resume time. For symmetry this
change also explicitly enables the controller at suspend time but
it's not strictly necessary.
Signed-off-by: Philipl Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Move the tps65010 header file from the OMAP arch directory to the
more generic <linux/i2c/...> directory, and remove the spurious
dependency of this driver on OMAP.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This patchis to add the first mmc controller support for pxa3xx.
It's valid for pxa3[0|1|2]0.
On zylonite, the first controller supports two slots, this patch
only support the first one right now.
Signed-off-by: Bridge Wu <bridge.wu@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch is to move pxamci DMA specific code to corresponding
platform layer because using DRCMRRXMMC/DRCMRTXMMC in pxamci.c makes
the driver code dedicated to platform which is not extensible.
It is applicable to all pxa platforms.
Signed-off-by: Bridge Wu <bridge.wu@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
pxa3[0|1]0 mmc controller can support 26MHz clock mode, they support
SD spec 1.1 and MMC spec 4.0 which specify high speed mode. So host
caps will include MMC_CAP_MMC_HIGHSPEED and MMC_CAP_SD_HIGHSPEED for
pxa3[0|1]0.
This patch is to add 26MHz support for them. pxa host clock will be
set to 26MHz mode when the card supported max clock rate is higher
than or equal to 26MHz.
Signed-off-by: Bridge Wu <bridge.wu@marvell.com>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The JMicron JMB38x chip doesn't support transfers that aren't 32-bit
aligned (both size and start address). It also doesn't like switching
between PIO and DMA mode, so it needs to be reset after each request.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some controllers have been designed on the assumption that all transfers
will be 32-bit aligned, both in start address and in size. This is not a
guarantee the SDHCI specification provides and not one we can provide.
Revert back to PIO for individual requests in order to work around the
hardware bug.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Given the patch which simplifies the spi_sync calling convention, this one
updates the callers of that routine which tried using it according to the
previous specification. (Most didn't.)
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is possible to handle arbitrary block sizes with tifm card reader by
conditionally switching to PIO in case such block has to be delivered. At
the beginning of each request, DMA is either disabled (non-power-of-2 block
size) or set to load time user preference.
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Fix:
WARNING: at arch/arm/mach-pxa/clock.c:69 clk_disable()
[<c002d7c8>] (dump_stack+0x0/0x14) from [<c00334f4>] (clk_disable+0x34/0xa0)
[<c00334c0>] (clk_disable+0x0/0xa0) from [<c028a43c>] (pxamci_set_ios+0x74/0xf0)
[<c028a3c8>] (pxamci_set_ios+0x0/0xf0) from [<c0281548>] (mmc_power_off+0x90/0x9c)
[<c02814b8>] (mmc_power_off+0x0/0x9c) from [<c0281a30>] (mmc_start_host+0x18/0x28)
[<c0281a18>] (mmc_start_host+0x0/0x28) from [<c02825a0>] (mmc_add_host+0xe8/0x104)
[<c02824b8>] (mmc_add_host+0x0/0x104) from [<c028a7d0>] (pxamci_probe+0x24c/0x2f4)
[<c028a584>] (pxamci_probe+0x0/0x2f4) from [<c01e5948>] (platform_drv_probe+0x20/0x24)
...
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
#include <scatterlist/scatterlist.h>
is an odd thing to do...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch 49dce689ad changed the sysfs data
structures for SPI in a way which broke the MMC-over-SPI host driver.
This patch fixes that regression by changing the scheme used to keep
from knowingly trying to use a shared bus segment, and updates the
adjacent comments slightly to better explain the issue.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Do a full scan of the directory to try and be a bit more proactive,
instead of waiting for things to break.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Commits
58b053e4ce ("Update arch/ to use sg helpers")
45711f1af6 ("[SG] Update drivers to use sg helpers")
fa05f1286b ("Update net/ to use sg helpers")
converted many files to use the scatter gather helpers without ensuring
that the necessary headerfile <linux/scatterlist> is included. This
happened to work for ia64, powerpc, sparc64 and x86 because they
happened to drag in that file via their <asm/dma-mapping.h>.
On most of the others this probably broke.
Instead of increasing the header file spider web I choose to include
<linux/scatterlist.h> directly into the affectes files.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A small MMC driver cleanup.
Use the defined AT91_MCI_ERRORS in at91_mci_completed_command() instead
of specifying all the error bits individually.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
AFAICS, fallout from repacing include of blkdev.h with include of bio.h.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the SPI framework and drivers stop using class_device. Update docs
accordingly ... highlighting just which sysfs paths should be
"safe"/stable.
Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (95 commits)
[ARM] 4578/1: CM-x270: PCMCIA support
[ARM] 4577/1: ITE 8152 PCI bridge support
[ARM] 4576/1: CM-X270 machine support
[ARM] pxa: Avoid pxa_gpio_mode() in gpio_direction_{in,out}put()
[ARM] pxa: move pxa_set_mode() from pxa2xx_mainstone.c to mainstone.c
[ARM] pxa: move pxa_set_mode() from pxa2xx_lubbock.c to lubbock.c
[ARM] pxa: Make cpu_is_pxaXXX dependent on configuration symbols
[ARM] pxa: PXA3xx base support
[NET] smc91x: fix PXA DMA support code
[SERIAL] Fix console initialisation ordering
[ARM] pxa: tidy up arch/arm/mach-pxa/Makefile
[ARM] Update arch/arm/Kconfig for drivers/Kconfig changes
[ARM] 4600/1: fix kernel build failure with build-id-supporting binutils
[ARM] 4599/1: Preserve ATAG list for use with kexec (2.6.23)
[ARM] Rename consistent_sync() as dma_cache_maint()
[ARM] 4572/1: ep93xx: add cirrus logic edb9307 support
[ARM] 4596/1: S3C2412: Correct IRQs for SDI+CF and add decoding support
[ARM] 4595/1: ns9xxx: define registers as void __iomem * instead of volatile u32
[ARM] 4594/1: ns9xxx: use the new gpio functions
[ARM] 4593/1: ns9xxx: implement generic clockevents
...
Make sure the mmc_spi driver can build without CONFIG_BLOCK.
Issue noted by "Avuton Olrich" <avuton@gmail.com> and randconfig.
While that won't be a common configuration, sometimes embedded
boards use SDIO to interface WLAN or Bluetooth chips (vs some
parallel interface), and don't provide an MMC/SD socket for use
with flash memory cards.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using weight32() to determine if a value is a power of 2 is a rather
heavi weight solution. The classic idiom is (x & (x - 1)) == 0, but
the kernel already provide a is_power_of_2 function for it.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The PXA has two transmit FIFOes, each32 byte deep. when one FIFO is
full and the other one has been transmitted, they are automatically
swapped and DMA is triggered for another 32 byte burst. However, when
there is less than 32 bytes left to send, the FIFO swap has to be done
manually. This is required for some SDIO transfers which are not
required to be multiples of 32 bytes.
A DMA completion interrupt is set for each descriptor which length isn't
a multiple of 32 in order to force the FIFO swap. While at it, the DMA
interrupt handler has been made a bit more resilient against errors.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The forcedma and nodma module parameters can be replaced with the quirks
parameter, so remove the redundancy.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some controllers like ENE712 can't work properly with DMA mode,
add this quirk to force these kinds of HW work with PIO mode
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Many host controllers don't fully follow the PCI spec to claim
whether they support DMA in PCI class register. Leave the driver
to judge it from the Capability register, quirks and module parameter
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Thanks to Matt Domsch and Rezwanul Kabir at Dell, we know how to disable the
MMC controller on the multi-function Ricoh R5C832. The MMC controller needs
to be disabled or it will steal MMC cards from the SD controller where they
would otherwise be supported by the Linux SDHCI driver.
Signed-off-by: Philipl Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Again, only available from PXA27x.
Signed-off-by: Bridge Wu <mingqiao.wu@gmail.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
From PXA27x, it is possible to do 4-bit data transfers.
Signed-off-by: Bridge Wu <mingqiao.wu@gmail.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
From PXA27x, it is possible to do 2048-byte block transfers.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Pending interrupts should be determined from both I_REG and I_MASK
registers.
Signed-off-by: Bridge Wu <mingqiao.wu@gmail.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The patch enables to define MMC host get_ro() method through platform data.
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This is the latest version of the MMC-over-SPI support. It works
on 2.6.23-rc2 plus git-mmc (from rc1-mm2), along with the preceding
patches which teach the rest of the MMC stack about SPI.
The main issue of note is that sometimes cards need to be power cycled
to recover after certain faults. Also, it may sometimes be necessary
to disable CRCs. ("modprobe mmc_core use_spi_crc=n")
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: mikael.starvik@axis.com,
Cc: Hans-Peter Nilsson <hp@axis.com>
Cc: Jan Nikitenko <jan.nikitenko@gmail.com>
Cc: Mike Lavender <mike@steroidmicros.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This kind of transfer is not supported, so don't advertise it and make it
fail early.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The MMC_DATA_MULTI flag never had a proper definition of what it
means, so remove it and let the drivers check the block count in
the request.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch fixes a bug in AT91 mmc host driver, that enables the wakeup
from suspend on card detection pin even if the card detect pin is not
available (==0). If not card detection pin is defined, IRQ0 == FIQ gets
enabled and if some activity is present on that pin, the system gets a
FIQ request, that causes a crash.
Signed-off-by: Anti Sullin <anti.sullin@artecdesign.ee>
Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
It is fully legal for a controller to start issuing data related
interrupts before it has signalled that the command has completed.
Make sure the driver actually can handle this.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some SDHC cards report an invalid maximum block size, in these cases
assume they support block sizes up to 512 bytes instead of returning
an error.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The block count register shouldn't be trusted for single block transfers,
so avoid using it completely when calculating transferred bytes.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some cleanup with whitespace/tab at the end of lines.
Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch fixes the following section mismatch warnings
...
WARNING: vmlinux.o(.init.text+0x29d40): Section mismatch: reference to .exit.text:wbsd_release_resources (between 'wbsd_init' and 'wbsd_probe')
WARNING: vmlinux.o(.init.text+0x29d49): Section mismatch: reference to .exit.text:wbsd_free_mmc (between 'wbsd_init' and 'wbsd_probe')
WARNING: vmlinux.o(.init.text+0x29f28): Section mismatch: reference to .exit.text:wbsd_free_mmc (between 'wbsd_init' and 'wbsd_probe')
...
Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Added its pci_id and implemented a quirk for it because this
controller needs to reset cmd and data when setting ios.
Signed-off-by: Leandro Dorileo <dorileo@ossystems.com.br>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some controllers signal "command complete" even on failures (which
they are allowed to do according to the spec). Make sure we check
the error bits first so we don't get any false positives.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The controller has a bit indicating that one of the higher bits (the
error bits) are set. A previous bug caused this bit to be masked, but
since that bug has been fixed we have to clear it explicictly.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This piece of code enable the system to be wake-up by a card insertion or removal.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (50 commits)
[ARM] sa1100: remove boot time RTC initialisation
[ARM] sa1100: stop doing our own rtc management over suspend
[ARM] 4474/1: Do not check the PSR_F_BIT in valid_user_regs
[ARM] 4473/2: Take the HWCAP definitions out of the elf.h file
[ARM] pxa: move platform devices to separate header file
[ARM] pxa: move device registration into CPU-specific file
[ARM] pxa: remove boot time RTC initialisation
[ARM] pxa: stop doing our own rtc management over suspend
[ARM] 4451/1: pxa: make dma.c generic and remove cpu specific dma code
[ARM] 4450/1: pxa: add pxa25x_init_irq() and pxa27x_init_irq()
[ARM] 4440/1: PXA: enable the checking of ICIP2 for IRQs
[ARM] 4438/1: PXA: remove #ifdef .. #endif from pxa_gpio_demux_handler()
[ARM] 4437/1: PXA: move the GPIO IRQ initialization code to pxa_init_irq_gpio()
[ARM] 4436/1: PXA: move low IRQ initialization code to pxa_init_irq_low()
[ARM] 4435/1: PXA: remove PXA_INTERNAL_IRQS
[ARM] 4434/1: PXA: remove PXA_IRQ_SKIP
[ARM] pxa: Fix PXA27x suspend type validation, remove pxa_pm_prepare()
[ARM] pxa: move pm_ops structure into CPU specific files
[ARM] pxa: introduce cpu_is_pxaXXX macros
[ARM] pxa: remove MMC register defines from pxa-regs.h
...
pxamci.h redefines the MMC registers differently so they can be used
with ioremap. Remove the incompatible definitions from pxa-regs.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fixes hanging using multi block operations (seen during CMD25).
Follows closely the datasheet flowcharts.
This piece of code handles better big file writing. I had to take care
of the notbusy signal during write (at91_mci_handle_cmdrdy function) and
to rearrange the AT91_MCI_ENDRX and AT91_MCI_RXBUFF flag usage.
Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Typo fix in at91_mci driver : standardized the typo
(at91_mci everywhere)
Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Whenever a power interrupt is signaled it is also reported as an unexpected
one. All other unexpected interrupts get lost. Cause is a not inversed
bitmask to remove power interrupts from the status.
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
ENE has a very weird design where an SDHCI device (0805) is presented
on the PCI bus, but that device is non-functional, and the real device
is hidden as a more generic device.
Signed-off-by: Milko Krachounov <milko@3mhz.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Ignoring OMAP_MMC_STAT_CARD_ERR, treating it as if the command
completed correctly.
Signed-off-by: Ragner Magalhaes <ragner.magalhaes@indt.org.br>
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Fix compilation error by removing command decoding from at91_mci.c driver.
Decoding commands in the host driver is the wrong way.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
... and make it depend on the response flag instead of the command type.
Signed-off-by: Nicolas Pitre <npitre@mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
When the device hits certain memory boundaries, it signals an
interrupt and expects to be serviced. We don't need the feature
but we need to make sure the device doesn't stall.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch has changed command types check from data flags.
MMC_STOP_TRANSMISSION is never passed to au1xmmc_send_command().
SEND_STOP() is used for MMC_STOP_TRANSMISSION.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Change Kconfig objects from "menu, config" into "menuconfig" so
that the user can disable the whole feature without having to
enter the menu first.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Socket power must be fully controlled by adapter driver. This also prevents
unnecessary power-off of the socket when media driver is unloaded, yet
media remains in the socket.
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Move divisor calculation into a separate function and re-arrange the
init order to make MMC_POWER_ON work.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
As discussed earlier on LKML:
http://lkml.org/lkml/2006/5/4/44
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch add a missing '\n' at the end of the 'cover is open' string
in mmc_omap_switch_handler().
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch makes the needlessly global tifm_sd_set_dma_data() static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Fix handling of low voltage MMC cards.
The latest MMC and SD specs both agree that support for
low-voltage operations is indicated by bit 7 in the OCR.
The MMC spec states that the low voltage range is
1.65-1.95V while the SD spec leaves the actual voltage
range undefined - meaning that there is still no such
thing as a low voltage SD card.
However, an old Sandisk spec implied that bits 7.0
represented voltages below 2.0V in 1V or 0.5V increments,
and the code was accordingly written with that expectation.
This confusion meant that host drivers attempting to support
the typical low voltage (1.8V) would set the wrong bits in
the host OCR mask (usually bits 5 and/or 6) resulting in the
the low voltage mode never being used.
This change corrects the low voltage range and adds sanity
checks on the reserved bits (0-6) and for SD cards that
claim to support low-voltage operations.
Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
