Convert the OMAP HDQ driver to use runtime PM. Compile- and boot-tested,
but not tested in actual use.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Tested-by: NeilBrown <neilb@suse.de>
HDQ/1-wire registers are 32 bits long, even if the register contents
fit into 8 bits, so accesses must be 32-bit aligned. Evidently the
OMAP2/3 interconnects allowed the driver to get away with 8 bit accesses,
but the OMAP4 puts a stop to that:
[ 1.488800] Driver for 1-wire Dallas network protocol.
[ 1.495025] Bad mode in data abort handler detected
[ 1.500122] Internal error: Oops - bad mode: 0 [#1] SMP
[ 1.505615] Modules linked in:
[ 1.508819] CPU: 0 Not tainted (3.3.0-rc1-00008-g45030e9 #992)
[ 1.515289] PC is at 0xffff0018
[ 1.518615] LR is at omap_hdq_probe+0xd4/0x2cc
The OMAP4430 ES2 Rev X TRM does warn about this restriction in section
23.2.6.2 "HDQ/1-Wire Registers".
Fixes the crash on OMAP4430 ES2 Pandaboard. Tested also on OMAP34xx and
OMAP2420; it seems to work fine on those chips, although due to the lack
of boards with HDQ/1-wire devices here, a more indepth test was not
possible.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Allow the OMAP HDQ1W driver to be built for all OMAP2+ SoCs by
adjusting KConfig dependencies. The previous dependency required
either SOC_OMAP2430 or ARCH_OMAP3 to be set, but the HDQ IP block is
present on OMAP2420 and OMAP44xx SoCs. The driver was still
selectable on multi-OMAP kernel configurations, however; so the
previous prohibition was rather pointless.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Direct inclusion of the asm header has long been deprecated by the
introduction of gpiolib.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This converts the remaining USB drivers in the kernel to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.
Added bonus is that it removes some unneeded kernel log messages about
drivers loading and/or unloading.
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Till Harbaum <till@harbaum.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Cc: Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Steve Glendinning <steve.glendinning@smsc.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes a regression in 3.0 reported by Paul Parsons regarding the
removal of the msleep(1) in the ds1wm_reset() function:
: The linux-3.0-rc4 DS1WM 1-wire driver is logging "bus error, retrying"
: error messages on an HP iPAQ hx4700 PDA (XScale-PXA270):
:
: <snip>
: Driver for 1-wire Dallas network protocol.
: DS1WM w1 busmaster driver - (c) 2004 Szabolcs Gyurko
: 1-Wire driver for the DS2760 battery monitor chip - (c) 2004-2005, Szabolcs Gyurko
: ds1wm ds1wm: pass: 1 bus error, retrying
: ds1wm ds1wm: pass: 2 bus error, retrying
: ds1wm ds1wm: pass: 3 bus error, retrying
: ds1wm ds1wm: pass: 4 bus error, retrying
: ds1wm ds1wm: pass: 5 bus error, retrying
: ...
:
: The visible result is that the battery charging LED is erratic; sometimes
: it works, mostly it doesn't.
:
: The linux-2.6.39 DS1WM 1-wire driver worked OK. I haven't tried 3.0-rc1,
: 3.0-rc2, or 3.0-rc3.
This sleep should not be required on normal circuitry provided the
pull-ups on the bus are correctly adapted to the slaves. Unfortunately,
this is not always the case. The sleep is restored but as a parameter to
the probe function in the pdata.
[akpm@linux-foundation.org: coding-style fixes]
Reported-by: Paul Parsons <lost.distance@yahoo.com>
Tested-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Jean-François Dagenais <dagenaisj@sonatest.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds multi-slave support of the w1 bus for the ds1wm Synthesizable
1-Wire Bus Master. Also many fixes and tweaks based on the rev3 of the
datasheet http://datasheets.maxim-ic.com/en/ds/DS1WM.pdf
Signed-off-by: Jean-François Dagenais <dagenaisj@sonatest.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
Cc: Matt Reimer <mreimer@vpop.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the addition of the platform device mfd_cell pointer, we can now
cleanly pass the sub device drivers platform data pointers through the
regular device platform_data one, and get rid of mfd_get_data().
Cc: Matt Reimer <mreimer@vpop.net>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
mfd_get_cell returns a const, so change the ds1wm client to store
a const mfd cell. This silences type mismatch warnings.
Since we're guaranteed to have the mfd_cell, we can also simplify
the code a bit to get rid of a temporary variable and NULL check.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Use mfd_data for passing information from mfd drivers to mfd
clients. The mfd_cell's driver_data field is being phased out.
Clients that were using driver_data now access .mfd_data
via mfd_get_data(). This changes ds1wm only; mfd drivers with
other cells are not modified, with the exception of led_cell.
The led_cell.driver_data line is dropped from htc-pasic3.c in this
patch as well. It's not used in mainline (there's no leds-pasic3
platform driver), so it should be safe to take care of that here.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
No need to explicitly set the cell's platform_data/data_size.
Modify clients to use mfd_get_cell helper function instead of
accessing platform_data directly.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This code makes two calls to clk_get, then test both return values and
fails if either failed.
The problem is that in the first inner if, where the first call to
clk_get has failed, it don't know if the second call has failed as well.
So it don't know whether clk_get should be called on the result of the
second call. Of course, it would be possible to test that value again.
A simpler solution is just to test the result of calling clk_get
directly after each call.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
position p1,p2;
expression e;
statement S;
@@
e = clk_get@p1(...)
...
if@p2 (IS_ERR(e)) S
@@
expression e;
statement S;
identifier l;
position r.p1, p2 != r.p2;
@@
*e = clk_get@p1(...)
... when != clk_put(e)
*if@p2 (...)
{
... when != clk_put(e)
* return ...;
}// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Amit Kucheria <amit.kucheria@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want to have just CONFIG_ARCH_OMAP2, 3 and 4. The rest
are nowadays just subcategories of these.
Search and replace the following:
ARCH_OMAP2420 SOC_OMAP2420
ARCH_OMAP2430 SOC_OMAP2430
ARCH_OMAP3430 SOC_OMAP3430
No functional changes.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thomas Weber <weber@corscience.de>
Acked-by: Sourav Poddar <sourav.poddar@ti.com>
Fixes the following error:
drivers/w1/masters/omap_hdq.c: In function 'hdq_wait_for_flag':
drivers/w1/masters/omap_hdq.c:137: error: implicit declaration of function 'schedule_timeout_uninterruptible'
drivers/w1/masters/omap_hdq.c: In function 'hdq_write_byte':
drivers/w1/masters/omap_hdq.c:177: error: 'TASK_UNINTERRUPTIBLE' undeclared (first use in this function)
drivers/w1/masters/omap_hdq.c:177: error: (Each undeclared identifier is reported only once
drivers/w1/masters/omap_hdq.c:177: error: for each function it appears in.)
drivers/w1/masters/omap_hdq.c:177: error: implicit declaration of function 'schedule_timeout'
drivers/w1/masters/omap_hdq.c: In function 'hdq_isr':
drivers/w1/masters/omap_hdq.c:221: error: 'TASK_NORMAL' undeclared (first use in this function)
drivers/w1/masters/omap_hdq.c: In function 'omap_hdq_break':
drivers/w1/masters/omap_hdq.c:316: error: 'TASK_UNINTERRUPTIBLE' undeclared (first use in this function)
Signed-off-by: Amit Kucheria <amit.kucheria@canonical.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
A pointer to omap_hdq_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded. Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.
An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Stanley.Miao <stanley.miao@windriver.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
This was found using a semantic patch, more info can be found at:
http://www.emn.fr/x-info/coccinelle/
Signed-off-by: Stoyan Gaydarov <sgayda2@uiuc.edu>
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>
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>
This patch adds support for the 1-wire master interface for i.MX27 and
i.MX31.
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uses clk_...() a lot
Acked-by: rmk+kernel@arm.linux.org.uk
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
OMAP LDP boot crash. This is because w1 subsystem changed the search
interface, so update omap_hdq's search interface to follow the change.
Signed-off-by: Stanley.Miao <stanley.miao@windriver.com>
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.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>
Drop the extra ds_wait_status() in ds_write_block().
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>
This replaces some magic numbers with marcos and corrects one marco.
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>
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: 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>
