Add a new helper function to instantiate an i2c device. It is meant as a
replacement for i2c_new_device() when you don't know for sure at which
address your I2C/SMBus device lives. This happens frequently on TV
adapters for example, you know there is a tuner chip on the bus, but
depending on the exact board model and revision, it can live at different
addresses. So, the new i2c_new_probed_device() function will probe the bus
according to a list of addresses, and as soon as one of these addresses
responds, it will call i2c_new_device() on that one address.
This function will make it possible to port the old i2c drivers to the
new model quickly.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add i2c_bit_add_numbered_bus(), which is equivalent to i2c_bit_add_bus
except that it calls i2c_add_numbered_adapter() at the end instead of
i2c_add_adapter().
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Make i2c-core.c obey Documentation/CodingStyle better by snugging
the EXPORT_SYMBOL declarations next to the relevant definitions.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This adds a call, i2c_add_numbered_adapter(), registering an I2C adapter
with a specific bus number and then creating I2C device nodes for any
pre-declared devices on that bus. It builds on previous patches adding
I2C probe() and remove() support, and that pre-declaration of devices.
This completes the core support for "new style" I2C device drivers.
Those follow the standard driver model for binding devices to drivers
(using probe and remove methods) rather than a legacy model (where the
driver tries to autoconfigure each bus, and registers devices itself).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This provides partial support for new-style I2C driver binding. It builds
on "struct i2c_board_info" declarations that identify I2C devices on a given
board. This is needed on systems with I2C devices that can't be fully probed
and/or autoconfigured, such as many embedded Linux configurations where the
way a given I2C device is wired may affect how it must be used.
There are two models for declaring such devices:
* LATE -- using a public function i2c_new_device(). This lets modules
declare I2C devices found *AFTER* a given I2C adapter becomes available.
For example, a PCI card could create adapters giving access to utility
chips on that card, and this would be used to associate those chips with
those adapters.
* EARLY -- from arch_initcall() level code, using a non-exported function
i2c_register_board_info(). This copies the declarations *BEFORE* such
an i2c_adapter becomes available, arranging that i2c_new_device() will
be called later when i2c-core registers the relevant i2c_adapter.
For example, arch/.../.../board-*.c files would declare the I2C devices
along with their platform data, and I2C devices would behave much like
PNPACPI devices. (That is, both enumerate from board-specific tables.)
To match the exported i2c_new_device(), the previously-private function
i2c_unregister_device() is now exported.
Pending later patches using these new APIs, this is effectively a NOP.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Update Documentation/i2c to match previous patches updating probe()
and remove() logic.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
More update for new style driver support: add a remove() method, and
use it in the relevant code paths.
Again, nothing will use this yet since there's nothing to create devices
feeding this infrastructure.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
One of a series of I2C infrastructure updates to support enumeration using
the standard Linux driver model.
This patch updates probe() and associated hotplug/coldplug support, but
not remove(). Nothing yet _uses_ it to create I2C devices, so those
hotplug/coldplug mechanisms will be the only externally visible change.
This patch will be an overall NOP since the I2C stack doesn't yet create
clients/devices except as part of binding them to legacy drivers.
Some code is moved earlier in the source code, helping group more of the
per-device infrastructure in one place and simplifying handling per-device
attributes.
Terminology being adopted: "legacy drivers" create devices (i2c_client)
themselves, while "new style" ones follow the driver model (the i2c_client
is handed to the probe routine). It's an either/or thing; the two models
don't mix, and drivers that try mixing them won't even be registered.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Port the i2c-pca-isa driver to the new device driver model. I'm
using Rene Herman's new isa bus type, as it fits the needs nicely. One
benefit is that we can now give a proper parent to our i2c adapter.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Port the i2c-elektor driver to the new device driver model. I'm
using Rene Herman's new isa bus type, as it fits the needs nicely. One
benefit is that we can now give a proper parent to our i2c adapter.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
When unloading the driver, we really want to unregister the i2c adapter
before we power it off, rather than the other way around.
Also speed up the bus a bit when we can sense SCL. The slaves will
stretch the line as needed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The scx200_acb driver supports two kind of devices, PCI ones and ISA
ones. Even ISA ones are detected using the presence of a given PCI
device, and we get a reference to it, but never put it back, so we
have a leak. Fix it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Initialize the fields of the i2c_adapter structure individually,
rather than copying a whole static template structure. This shaves
off 474 bytes or 14% (on i386) from the binary size.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Now that i2c-core lets the i2c bus drivers emulate the SMBus block read
and SMBus block process call transaction types, let's implement that in
the popular i2c bit-banging driver. This will also act as a reference
implementation for other bus drivers which want to do the same.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Let the I2C bus drivers emulate the SMBus Block Read and Block Process
Call transactions if they wish. This requires to define a new message
flag, which i2c-core will use to let the underlying I2C bus driver
know that the first received byte will specify the length of the read
message.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The i2c-algo-bit driver doesn't behave well on read errors: it'll
bail out without even sending a stop condition on the bus, so the bus
will be stuck. So make sure that we always send a stop condition on
the bus before we leave. The best way to make sure is to always send
it at the end of function bit_xfer.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Rename dev_to_i2c_adapter() as to_i2c_adapter(), since the previous
syntax was a surprising and needless difference from normal naming
conventions in Linux.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This patch is a minor cleanup/code shrink, using class infrastructure
in i2c-core to manage the i2c_adapter attribute.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This shrinks the size of "struct i2c_client" by 40 bytes:
- Substantially shrinks the string used to identify the chip type
- The "flags" don't need to be so big
- Removes some internal padding
It also adds kerneldoc for that struct, explaining how "name" is really a
chip type identifier; it's otherwise potentially confusing.
Because the I2C_NAME_SIZE symbol was abused for both i2c_client.name
and for i2c_adapter.name, this needed to affect i2c_adapter too. The
adapters which used that symbol now use the more-obviously-correct
idiom of taking the size of that field.
JD: Shorten i2c_adapter.name from 50 to 48 bytes while we're here, to
avoid wasting space in padding.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Minor cleanup in i2c_register_driver(): use list_for_each_entry().
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Kill i2c_adapter_driver as it doesn't make sense and it prevents
further i2c-core cleanups. i2c_adapter devices are virtual devices
(ex-class devices) and as such they don't need a driver.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Kill i2c_adapter.class_dev. Instead, set the class of i2c_adapter.dev
to i2c_adapter_class, so that a symlink will be created for every
i2c_adapter in /sys/class/i2c-adapter.
The same change must be mirrored to i2c-isa as it duplicates some
of the i2c-core functionalities.
User-space tools and libraries might need some adjustments. In
particular, libsensors from lm_sensors 2.10.3 or later is required for
proper discovery of i2c adapter names after this change.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This is a trivial and hopefully obviously correct patch to setup
and teardown the identity mappings the way the rest of arch/i386
does.
My new page table setup code will break some assumptions below so
this is my attempt to keep voyager working.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
full kthread conversion on the voyager power switch handling thread.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This isn't true for voyager, so alter setup_pit_timer() to initialise
the cpumask from the current processor id (which should be the boot
processor) rather than defaulting to zero.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
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>
Since many have the system root on MMC/SD we must allow some foot
shooting when it comes to resume.
We cannot detect if a card is removed and reinserted during suspend,
so the safe approach would be to assume it was, avoiding potential
filesystem corruption. This will of course not work if you cannot
release the card before suspend.
This commit adds a compile time option that makes the MMC layer
assume the card wasn't touched if it is redetected upon resume.
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>
libata previously depended upon waits in prereset to get resets after
hotplug right for both spin up and device ready wait. This was
necessary both for reliablity and speed as reset was likely to fail if
initiated too early and each try usually took more than 30secs to
fail. Previous patches fixed the reliability part by fixing status
and SCR handling in resets. This patch remedies the speed part by
improving reset sequencing.
Prereset waiting timeout is adjusted to 10s because spinup wait is
replaced by reset sequencing and !BSY wait is not as important as
before. During boot or module loading where the drive is already
fully spun up, !BSY wait succeeds immediately, so 10s should be enough
in most cases. It matters after hotplugging or other error
conditions, but in those cases, !BSY wait in prereset simply can't be
relied upon due to the varied and weird behaviors ATA controllers and
devices show.
Reset is now driven by ata_eh_reset_timeouts[] table which contains
timeouts for each reset try. The first reset can be softreset but the
following ones are always hardreset if available. Each timeout
defines deadline for the reset try. If a reset try fails, reset is
retried with the next timeout till the end of the timeout table is
reached. If a reset try fails before the timeout with error, libata
waits till the deadline of the failed try before retrying.
IOW, the timeout table defines timetable of reset tries such that the
n'th try always begins at least after the sum of all previous timeouts
has passed. The current timetable defines 4 tries and takes around 1
minute.
@0 : First try. This should succeed most of the time during boot.
@10 : 10s is enough to spin up most consumer harddrives. Give it
another shot.
@20 : 20s should spin up > 99% of working drives. This has 30s
timeout for retarded devices needing long idleness post reset.
@55 : Final try with 5s timeout just in case.
The above timetable is trade off between not annoying the device too
much with frequent resets and taking reasonable amount of time in most
cases. Some controllers may do better with shorter timeouts while
others may fare better with longer but we just can't rely upon LLD
writers to test each controller with wide variety of devices using
various scenarios. We need default behavior which reasonably fits
most cases.
I've tested the above timetable on a dozen SATA controllers and a few
PATA controllers with about a dozen different drives from all major
vendors and 4 different ODDs from three different vendors for both
boot and hotplug (if available) cases.
Boot probing is not affected unless the device is broken in which
cases new code gives up on the port after a minute rather than five or
nine minutes. When hotplugging, most devices get detected on the
first or second try. Multi-platter drives with long spin up time
which sometimes took > 40 secs with the original code, now usually
comes up during the second try and at least right after the third try
@20.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch updates ata_std_prereset() as follows.
* Don't fail on phy resume failure. Just whine and continue. Failure
from prereset makes libata abort whole reset sequence and give up
the port, so prereset() should be best effort. This is more
important with the coming EH updates as prereset() will be called
with shorter timeout.
* If ata_wait_ready() fails, whine and request hardreset instead.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
For PATA, 0xff status indicates empty port. For SATA, it depends on
how the controller emulates status register. On some controllers,
0xff is used to represent broken link or certain stage during reset.
libata currently deals SATA the same. This hasn't caused any problem
because problematic situations usually only occur after hotplug or
other link disruption events and libata blindly waited for the device
to spin up and settle after hotplug giving the link and device
whatever time to go through those stages.
libata is going to replace unconditional spinup wait with generic
timed sequence of resets, so not only getting 0xff handling right for
SATA is, well, the right thing to do, it's much more important now.
This patch makes the following changes.
* Make ata_bus_softreset() return -ENODEV if any of its wait fails
due to 0xff status.
* Fail soft/hardreset if status wait returns -ENODEV indicating 0xff
status while SStatus says the link is online. e.g. Reset fails if
status is 0xff after reset when SStatus reports the linke is online.
If SCR registers are not available, everything is the same as
before.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add @deadline to prereset and reset methods and make them honor it.
ata_wait_ready() which directly takes @deadline is implemented to be
used as the wait function. This patch is in preparation for EH timing
improvements.
* ata_wait_ready() never does busy sleep. It's only used from EH and
no wait in EH is that urgent. This function also prints 'be
patient' message automatically after 5 secs of waiting if more than
3 secs is remaining till deadline.
* ata_bus_post_reset() now fails with error code if any of its wait
fails. This is important because earlier reset tries will have
shorter timeout than the spec requires. If a device fails to
respond before the short timeout, reset should be retried with
longer timeout rather than silently ignoring the device.
There are three behavior differences.
1. Timeout is applied to both devices at once, not separately. This
is more consistent with what the spec says.
2. When a device passes devchk but fails to become ready before
deadline. Previouly, post_reset would just succeed and let
device classification remove the device. New code fails the
reset thus causing reset retry. After a few times, EH will give
up disabling the port.
3. When slave device passes devchk but fails to become accessible
(TF-wise) after reset. Original code disables dev1 after 30s
timeout and continues as if the device doesn't exist, while the
patched code fails reset. When this happens, new code fails
reset on whole port rather than proceeding with only the primary
device.
If the failing device is suffering transient problems, new code
retries reset which is a better behavior. If the failing device is
actually broken, the net effect is identical to it, but not to the
other device sharing the channel. In the previous code, reset would
have succeeded after 30s thus detecting the working one. In the new
code, reset fails and whole port gets disabled. IMO, it's a
pathological case anyway (broken device sharing bus with working
one) and doesn't really matter.
* ata_bus_softreset() is changed to return error code from
ata_bus_post_reset(). It used to return 0 unconditionally.
* Spin up waiting is to be removed and not converted to honor
deadline.
* To be on the safe side, deadline is set to 40s for the time being.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Consolidate the list of available voltages.
Up until now, a separate set of defines has been
used for host->vdd than that used for the OCR
voltage mask values. Having two sets of defines
allows them to get out of sync and the current
sets are already inconsistent with one claiming
to describe ranges and the other specific voltages.
Only the SDHCI driver uses the host->vdd defines and
it is easily fixed to use the OCR defines.
Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Delegate protocol handling to "bus handlers". This allows the core to
just handle the task of arbitrating the bus. Initialisation and
pampering of cards is now done by the different bus handlers.
This design also allows MMC and SD (and later SDIO) to be more cleanly
separated, allowing easier maintenance.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Move the check for supported data opcodes to the beginning of the
request function to avoid wedging the card.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Move protocol operations and definitions into their own files
in an effort to separate protocol handling and bus
arbitration more clearly.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
