Improve the debugging features of the i2c-algo-bit driver:
* Make it possible to compile the driver without debugging support
at all, making it much smaller.
* Use dev_dbg() for debugging messages where possible, and dev_err()
for error messages.
* Remove redundant debugging messages.
These changes allowed for minor code cleanups, which are included
as well.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The original i2c-algo-bit implementation uses a 33/66 SCL duty cycle
when bits are being written on the bus. While the I2C specification
doesn't forbid it, this prevents us from driving the I2C bus to its
max speed, limiting us to 66 kbps max on standard I2C busses.
Implementing a 50/50 duty cycle instead lets us max out the bandwidth
up to the theoretical max of 100 kbps on standard I2C busses. This is
particularly important when large amounts of data need to be transfered
over the bus, as is the case with some TV adapters when the firmware is
being uploaded.
In fact this change even allows, at least in theory, fast-mode I2C
support at 125, 166 and 250 kbps. There's no way to reach the
theoretical max of 400 kbps with this implementation. But I don't
think we want to put efforts in that direction anyway: software-driven
I2C is very CPU-intensive and bad for latency.
Other timing changes:
* Don't set SDA high explicitly on error, we're going to issue a stop
condition before we leave anyway.
* If an error occurs when sending the slave address, yield the CPU
before retrying, and remove the additional delay after the new start
condition.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Update the OMAP I2C driver to use i2c_add_numbered_adapter(), so that
later patches can convert boards to using new-style drivers.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The i2c linux driver for blackfin architecture which supports blackfin
on-chip TWI controller i2c operation.
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Make i2c_del_driver a void function, like all other driver removal
functions. It always returned 0 even when errors occured, and nobody
ever actually checked the return value anyway. And we cannot fail
a module removal anyway.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Move the declaration of i2c-isa-only exported symbols to i2c-isa
itself, that's the best way to ensure nobody will attempt to use them.
Hopefully we'll get rid of the exports themselves soon anyway.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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>
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>
* Last write during i2c_xfer is of the wrong byte (off-by-1).
* Read length is wrong for some of the reads (mistakenly used the PEC
version)
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Looks like a local change I made to be able to test-compile the i2c-pasemi
driver leaked upstream.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Check if workqueue creation failed. Further usage of NULL pointed
workqueue is not good I guess ;)
Signed-off-by: Cyrill V. Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Restore the original host configuration on driver unload and on
suspend. In particular this returns the SMBus master in I2C mode if it
was originally in I2C mode, which should help with suspend/resume if
the BIOS expects to find the SMBus master in I2C mode.
This fixes bug #6449 (for real this time.)
http://bugzilla.kernel.org/show_bug.cgi?id=6449
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Tommi Kyntola <tommi.kyntola@ray.fi>
Move the Acorn IOC/IOMD I2C bus driver from drivers/i2c, strip
out the reminants of the platform specific parts of the old
PCF8583 RTC code, and remove the old obsolete PCF8583 driver.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits)
Documentation/kernel-docs.txt update.
arch/cris: typo in KERN_INFO
Storage class should be before const qualifier
kernel/printk.c: comment fix
update I/O sched Kconfig help texts - CFQ is now default, not AS.
Remove duplicate listing of Cris arch from README
kbuild: more doc. cleanups
doc: make doc. for maxcpus= more visible
drivers/net/eexpress.c: remove duplicate comment
add a help text for BLK_DEV_GENERIC
correct a dead URL in the IP_MULTICAST help text
fix the BAYCOM_SER_HDX help text
fix SCSI_SCAN_ASYNC help text
trivial documentation patch for platform.txt
Fix typos concerning hierarchy
Fix comment typo "spin_lock_irqrestore".
Fix misspellings of "agressive".
drivers/scsi/a100u2w.c: trivial typo patch
Correct trivial typo in log2.h.
Remove useless FIND_FIRST_BIT() macro from cardbus.c.
...
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (117 commits)
[ARM] 4058/2: iop32x: set ->broken_parity_status on n2100 onboard r8169 ports
[ARM] 4140/1: AACI stability add ac97 timeout and retries
[ARM] 4139/1: AACI record support
[ARM] 4138/1: AACI: multiple channel support for IRQ handling
[ARM] 4211/1: Provide a defconfig for ns9xxx
[ARM] 4210/1: base for new machine type "NetSilicon NS9360"
[ARM] 4222/1: S3C2443: Remove reference to missing S3C2443_PM
[ARM] 4221/1: S3C2443: DMA support
[ARM] 4220/1: S3C24XX: DMA system initialised from sysdev
[ARM] 4219/1: S3C2443: DMA source definitions
[ARM] 4218/1: S3C2412: fix CONFIG_CPU_S3C2412_ONLY wrt to S3C2443
[ARM] 4217/1: S3C24XX: remove the dma channel show at startup
[ARM] 4090/2: avoid clash between PXA and SA1111 defines
[ARM] 4216/1: add .gitignore entries for ARM specific files
[ARM] 4214/2: S3C2410: Add Armzone QT2410
[ARM] 4215/1: s3c2410 usb device: per-platform vbus_draw
[ARM] 4213/1: S3C2410 - Update definition of ADCTSC_XY_PST
[ARM] 4098/1: ARM: rtc_lock only used with rtc_cmos
[ARM] 4137/1: Add kexec support
[ARM] 4201/1: SMP barriers pair needed for the secondary boot process
...
Fix up conflict due to typedef removal in sound/arm/aaci.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Enable svc access to cp6 via an undefined instruction hook. Do not enable
access for usr code.
This patch also makes iop13xx select PLAT_IOP, this requires a small change
to drivers/i2c/busses/i2c-iop3xx.c.
Per Lennert Buytenhek's note, the cp6 trap routine is moved to arch/arm/plat-iop
Per Nicolas Pitre's note, the cp_wait is skipped since the latency to
return to the faulting function is longer than cp_wait.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now that the i2c_adapter migration plan changed and we are going to
keep i2c_adapter.dev, it's no longer that urgent to add a proper device
to all i2c_adapter drivers. Thus is seems resonable to degrade the
warning asking authors to migrate their driver to a debug message.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Declare the parent device of i2c_adapter devices each time we can
easily do so. It makes the i2c_adapter appear at the right place in
the device tree, rather than as a platform device.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: Jody McIntyre <scjody@modernduck.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: v4l-dvb-maintainer@linuxtv.org
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Proposed cleanups to the i2c-amd8111 SMBus driver:
* Fold long lines.
* Add an explicit mask when writing the low byte of a word.
* Use I2C_SMBUS_BLOCK_MAX instead of hardcoding 32.
* Discard extra blank lines.
* Use boolean not instead of bitwise not for bit tests, it's clearer.
* Return -EBUSY rather than -1 on I/O resource conflict.
* Fix a race on device registration, initialization should be done
before the bus is registered.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This simple patch adds support to i2c-parport for the One For All remote
JP1 parallel port interfaces which can be found detailed at:
http://www.hifi-remote.com/jp1/hardware.shtml
These allow access to the internal configuration EEPROM on various
remote controls and there are a variety of Windows tools that make use
of this hardware. I have tested this patch with the "simple" parallel
port device and a One For All URC-7562 and confirmed that the data read
using the eeprom i2c driver matches that returned by the Windows "IR"
JP1 tool.
Signed-off-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
We do not have any documentation for the CX700, but it was reported
to work fine. Thanks to Claas Langbehn for testing.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
IDs have been defined but not used by most of the I2C adapters.
By having a unique ID, clients can check for correct connection
during probe.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Driver model updates for the I2C core:
- Add new suspend(), resume(), and shutdown() methods. Use them in the
standard driver model style; document them.
- Minor doc updates to highlight zero-initialized fields in drivers, and
the driver model accessors for "clientdata".
If any i2c drivers were previously using the old suspend/resume calls
in "struct driver", they were getting warning messages ... and will
now no longer work. Other than that, this patch changes no behaviors;
and it lets I2C drivers use conventional PM and shutdown support.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
