There is no point in implementing a detect callback for the DS2482, as
this device can't be detected. It was there solely to handle "force"
module parameters to instantiate devices, but now we have a better sysfs
interface that can do the same.
So we can get rid of the ugly module parameters and the detect callback.
This shrinks the binary module size by 21%.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Ben Gardner <gardner.ben@gmail.com>
On embedded devices, sleep mode conditions can be tricky to handle,
Especially when processors tend to pull-down the w1 bus during sleep. Bus
slaves (such as the ds2760) may interpret this as a reason for power-down
conditions and entirely switch off the device.
This patch adds a callback function pointer to let users switch on and off
the external pull-up resistor. This lets the outside world know whether
the processor is currently actively driving the bus or not.
When this callback is not provided, the code behaviour won't change.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Ville Syrjala <syrjala@sci.fi>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
.ko is normally not included in Kconfig help, make it consistent.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This driver requests a clock that usually is supplied by the MFD in which
the DS1WM is contained. Currently, it is impossible for a MFD to register
their clocks with the generic clock API due to different implementations
across architectures.
For now, this patch removes the clock handling from DS1WM altogether,
trusting that the MFD enable/disable functions will switch the clock if
needed. The clock rate is obtained from a new parameter in driver_data.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
This patch converts the DS1WM driver into an MFD cell. It also
calculates the bus_shift parameter from the memory resource size.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
The context makes it clear already that these are clocks, so there's
no need for such a suffix. This patch only changes the clocks actually
used in the tree. The remaining clocks are renamed in the subsequent
architecture specific patches.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
W1 master implementations are expected to return 0 or 1 from their
read_bit() function. However, not all platforms do return these values
from gpio_get_value() - namely PXAs won't. Hence the w1 gpio-master needs
to break the result down to 0 or 1 itself.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Ville Syrjala <syrjala@sci.fi>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: Felipe Balbi <felipe.balbi@nokia.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
