Provide the BQ27000 slave interface driver.

Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The HDQ/1-Wire module of TI OMAP2430/3430 platforms implement the hardware
protocol of the master functions of the Benchmark HDQ and the Dallas
Semiconductor 1-Wire protocols.  These protocols use a single wire for
communication between the master (HDQ/1-Wire controller) and the slave
(HDQ/1-Wire external compliant device).

This patch provides the HDQ driver to suppport TI OMAP2430/3430 platforms.

Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
Acked-by: NFelipe Balbi <felipe.balbi@nokia.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Export the w1_read_8 function for use of drivers.  The OMAP HDQ
driver(drivers/w1/masters/omap_hdq.c) uses this function.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Tejun's commit 7b595756 made sysfs
attribute->owner unnecessary.  But the field was left in the structure to
ease the merge.  It's been over a year since that change and it is now
time to start killing attribute->owner along with its users - one arch at
a time!

This patch is attempt #1 to get rid of attribute->owner only for
CONFIG_X86_64 or CONFIG_X86_32 .  We will deal with other arches later on
as and when possible - avr32 will be the next since that is something I
can test.  Compile (make allyesconfig / make allmodconfig / custom config)
and boot tested.

akpm: the idea is that we put the declaration of sttribute.owner inside
`#ifndef CONFIG_X86'.  But that proved to be too ambitious for now because
new usages kept on turning up in subsystem trees.

[akpm: remove the ifdef for now]
Signed-off-by: NParag Warudkar <parag.lkml@gmail.com>
Cc: Greg KH <greg@kroah.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

[akpm@linux-foundation.org: minor fixlets and cleanups]
Signed-off-by: NBernhard Weirich <bernhard.weirich@riedel.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Optimize the ds_set_pullup function.  For a strong pullup to be sent the
ds2490 has to have both the strong pullup mode enabled, and the specific
write operation has to have the SPU bit enabled.  Previously the write
always had the SPU bit enabled and both the duration and model was set
when a strong pullup was requested.  Now the strong pullup mode is enabled
at initialization time, the delay is updated only when the value changes,
and the write SPU bit is set only when a strong pullup is required.  This
removes two or three bus transactions per strong pullup request.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Drop the extra ds_wait_status() in ds_write_block().
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This replaces some magic numbers with marcos and corrects one marco.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reset the device in init as it can be in a bad state.  This is necessary
because a block write will wait for data to be placed in the output buffer
and block any later commands which will keep accumulating and the device
will not be idle.  Another case is removing the ds2490 module while a bus
search is in progress, somehow a few commands get through, but the input
transfers fail leaving data in the input buffer.  This will cause the next
read to fail see the note in ds_recv_data.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ds_reset no longer calls ds_wait_status, the result wasn't used and it
would only delay the following data operations.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- add result register #defines
- rename ds_dump_status to ds_print_msg
- rename ds_recv_status to ds_dump_status
- ds_dump_status prints the requested status and no longer reads the
  status, this is because the second status read can return different
  data for example the result register
- the result register will be printed, though limited to detecting a
  new device, detecting other values such as a short would require
  additional reporting methods
- ST_EPOF was moved to ds_wait_status to clear the error condition
  sooner
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simplify and fix ds_touch_bit.  If a device is attached in the middle of a
bus search the status register will return more than the default 16 bytes.
 The additional bytes indicate that it has detected a new device.  The way
ds_wait_status is coded, if it doesn't read 16 status bytes it returns an
error value.  ds_touch_bit then will detect that error and return an
error.  In that case it doesn't read the input buffer and returns
uninitialized data.  It doesn't stop there.  The next transaction will not
expect the extra byte in the input buffer and the short read will cause an
error and clear out both the old byte and new data in the input buffer.

Just ignore the value of ds_wait_status.  It is still required to wait
until ds2490 is again idle and there is data to read when ds_recv_data is
called.  This also removes the while loop.  None of the other commands
wait and verify that the issued command is in the status register.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't export read and write bit operations, they didn't work, they weren't
used, and they can't be made to work.  The one wire low level bit
operations expect to set high or low levels, the ds2490 hardware only
supports complete read or write time slots, better to just comment them
out.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ds_write_bit doesn't read the input buffer, so add COMM_ICP and a comment
that it will no longer generate a read back data byte.  If there is an
extra data byte later on then it will cause an error and discard what data
was there.  Corrected operator ordering for ds_send_control.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add strong pullup support for ds2490 driver, also drop mdelay(750), which
busy waits, usage in favour of msleep for long delays.  Now with msleep
only being called when the strong pullup is active, one wire bus
operations are only taking minimal system overhead.

The new set_pullup will only enable the strong pullup when requested,
which is expected to be the only write operation that will benefit from a
strong pullup.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Corrected print message, it was writing not reading, this also prints the
endpoint used for the write instead of hardcoding it.  Failed to write
1-wire data to ep0x%x: err=%d.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Like the previous w1_io.c reset coments and msleep patch, I don't have the
hardware to verify the change, but I think it is safe.  It also helps to
see a comment like this in the code.  "We'll wait a bit longer just to be
sure." If they are going to calculate delaying 324.9us, but actually delay
500us, why not just give up the CPU and sleep?  This is designed for a
battery powered ARM system, avoiding busywaiting has to be good for
battery life.

I sent a request for testers March 7, 2008 to the Linux kernel mailing
list and two developers who have patches for ds1wm.c, but I didn't get
any respons.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

w1_reset_bus, added some comments about the timing and switched to msleep
for the later delay.  I don't have the hardware to test the sleep after
reset change.  The one wire doesn't have a timing requirement between
commands so it is fine.  I do have the USB hardware and it would be in big
trouble with 10ms interrupt transfers to find that the reset completed.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

s/printk/dev_dbg/
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Follow the example of other devices (like the joystick device).  Pick the
first available id for each detected device.  Currently for USB devices,
suspending and resuming would cause the number to increment.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sl->master->mutex and dev->mutex refer to the same mutex variable, but be
consistent and use the same set of pointers for the lock and unlock calls.
 It is less confusing (and one less pointer dereference this way).
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Removed the w1_family structure member variable need_exit.  It was only
being set and never used.  Even if it were to be used it is a polling type
operation.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixed data reading bug by replacing binary attribute with device one.

Switching the sysfs read from bin_attribute to device_attribute.  The data
is far under PAGE_SIZE so the binary interface isn't required.  As the
device_attribute interface will make one call to w1_therm_read per file
open and buffer, the result is, the following problems go away.

buffer overflow:
	Execute a short read on w1_slave and w1_therm_read_bin would still
	return the full string size worth of data clobbering the user space
	buffer when it returned.  Switching to device_attribute avoids the
	buffer overflow problems.  With the snprintf formatted output dealing
	with short reads without doing a conversion per read would have
	been difficult.
bad behavior:
	`cat w1_slave` would cause two temperature conversions to take place.
	Previously the code assumed W1_SLAVE_DATA_SIZE would be returned with
	each read.  It would not return 0 unless the offset was less
	than W1_SLAVE_DATA_SIZE.  The result was the first read did a
	temperature conversion, filled the buffer and returned, the
	offset in the second read would be less than
	W1_SLAVE_DATA_SIZE and also fill the buffer and return, the
	third read would finnally have a big enough offset to return 0
	and cause cat to stop.  Now w1_therm_read will be called at
	most once per open.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix bug reading the id sysfs file.  If less than the full 8 bytes were
read, the next read would start at the first byte instead of continuing.
It needed the offset added to memcpy, or the better solution was to
replace it with the device attribute instead of bin attribute.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Added a new module parameter search_count which allows overriding the
default search count.  -1 continual, 0 disabled, N that many times.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simplified the logic in w1_slave_found by using the new
w1_attach_slave_device function to find a slave and mark it as active or
add the device if the crc checks.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sysfs entries were added to manually add and remove slave devices.  This
is useful if the automatic bus searching is disabled, and the device ids
are already known.

[akpm@linux-foundation.org: fix printk types]
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Added strong pullup to thermal sensor driver and general documentation on
the sensor.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a strong pullup option to the w1 system.  This supplies extra power
for parasite powered devices.  There is a w1_master_pullup sysfs entry and
enable_pullup module parameter to enable or disable the strong pullup.

The one wire bus requires at a minimum one wire and ground.  The common
wire is used for sending and receiving data as well as supplying power to
devices that are parasite powered of which temperature sensors can be one
example.  The bus must be idle and left high while a temperature
conversion is in progress, in addition the normal pullup resister on
larger networks or even higher temperatures might not supply enough power.
 The pullup resister can't provide too much pullup current, because
devices need to pull the bus down to write a value.  This enables the
strong pullup for supported hardware, which can supply more current when
requested.  Unsupported hardware will just delay with the bus high.

The hardware USB 2490 one wire bus master has a bit on some commands which
will enable the strong pullup as soon as the command finishes executing.
To use strong pullup, call the new w1_next_pullup function to register the
duration.  The next write command will call set_pullup before sending the
data, and reset the duration to zero once it returns.

Switched from simple_strtol to strict_strtol.
Signed-off-by: NDavid Fries <david@fries.net>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The w1_process thread's sleeping and termination has been modified.
msleep_interruptible was replaced by schedule_timeout and schedule to
allow for kthread_stop and wake_up_process to interrupt the sleep and the
unbounded sleeping when a bus search is disabled.  The W1_MASTER_NEED_EXIT
and flags variable were removed as they were redundant with
kthread_should_stop and kthread_stop.  If w1_process is sleeping,
requesting a search will immediately wake it up rather than waiting for
the end of msleep_interruptible previously.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move the creation of the w1_process thread to after the device has been
initialized.  This way w1_process doesn't have to check to see if it has
been initialized and the bus search can proceed without sleeping.  That
also eliminates two checks in the w1_process loop.  The sleep now happens
at the end of the loop not the beginning.

Also added a comment for why the atomic_set was 2.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Early abort if the master driver or the hardware goes away in the middle
of a bus search operation.  The alternative is to spam the print buffer up
to 64*64 times with read errors in the case of USB.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

w1_control_thread was removed which would wake up every second and process
newly registered family codes and complete some final cleanup for a
removed master.  Those routines were moved to the threads that were
previously requesting those operations.  A new function
w1_reconnect_slaves takes care of reconnecting existing slave devices when
a new family code is registered or removed.  The removal case was missing
and would cause a deadlock waiting for the family code reference count to
decrease, which will now happen.  A problem with registering a family code
was fixed.  A slave device would be unattached if it wasn't yet claimed,
then attached at the end of the list, two unclaimed slaves would cause an
infinite loop.

The struct w1_bus_master.search now takes a pointer to the struct
w1_master device to avoid searching for it, which would have caused a
lock ordering deadlock with the removal of w1_control_thread.
Signed-off-by: NDavid Fries <david@fries.net>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new-style ds2482 driver implements the optional detect() callback
to cover the use cases of the legacy driver. I'm curious if anyone
really needs this though, so it might be removed in the feature.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The patch replaces dev_dbg() by dev_err(), so the user could actually see the
error, instead of wondering why w1 doesn't work.  The root cause of the bus
reset error isn't yet debugged though, but this sometimes happens on iPaq
H5555.

And while I'm at it, some cosmetic cleanups also made (few lines were using
spaces instead of tabs).
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On the error condition clk_get() returns ERR_PTR(..), so checking for NULL
doesn't work.  ds1wm module causes a kernel oops when ds1wm clock isn't
registered.

This patch converts NULL check to IS_ERR(), plus uses PTR_ERR()
for the return code.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The DS1WM driver incorrectly infers the IAS bit (1-wire interrupt active
high) from IRQ settings.  There are devices that have IAS=0 but still need
the IRQ to trigger on a rising edge.  With this patch, machines with DS1WM
that need IAS=1 have to set .active_high=1 in the ds1wm_platform_data.
Signed-off-by: NPhilipp Zabel <philipp.zabel@gmail.com>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Acked-by: NMatt Reimer <mreimer@vpop.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a GPIO 1-wire bus master driver.  The driver used the GPIO API to
control the wire and the GPIO pin can be specified using platform data
similar to i2c-gpio.  The driver was tested with AT91SAM9260 + DS2401.
Signed-off-by: NVille Syrjala <syrjala@sci.fi>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Standardize the temperature units to millidegrees C for the two sensor
conversion routines.  Previously the routines were,

w1_DS18B20_convert_temp degrees C
w1_DS18S20_convert_temp millidegrees C

Unfortunately this will break any program using the ds18b20 value as it
will now be 1000 times bigger.  Fortunately there can't be that many users
out there, or some of these bugs will have been fixed by now, such as the
negative C error (see previous patch) that makes me think the ds18b20 is
the better choice to change because of the current bugs.
Signed-off-by: NDavid Fries <david@fries.net>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>