This DS2408 w1 slave driver is not complete for all the features of the
chip, but its sufficient if you use it as a simple IO expander.
[randy.dunlap@oracle.com: fix w1_ds2408.c printk formats]
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: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The first patch adds generic functionnality to w1_io for Resume Command
[A5h] lots of slaves support. I found it useful for multi-commands/reset
workflows with the same slave on a multi-slave bus.
This DS2408 w1 slave driver is not complete for all the features of the
chip, but its sufficient if you use it as a simple IO expander. Enjoy!
The ds1wm had Kconfig dependencies towards ARM && HAVE_CLK. I took them
out since I was using the ds1wm on an x86_64 platform (ds1wm in a FPGA
through pcie) and found them irrelevant.
The clock freq/divisors at the top of ds1wm.c did not have the MSB set to
1. This bit is CLK_EN which turns the whole prescaler and dividers on.
The driver never mentionned this bit either, so I just included this bit
right in the table entries. I also took the liberty to add a couple of
entries to the table. The spec doesn't explicitely mentions these
possibilities but the description and examination of the core shows the
prescalers & dividers can be used for more than the table explicitely
shows. The table I enlarged still doesn't cover all possibilities, but
it's a good start.
I also made a few tweaks to a couple of the read and write algorithms
which made sense while I had my head very deep in the ds1wm documentation.
We stressed it a lot with 10+ slaves on the bus, many ds2408, ds2431 and
ds2433 at the same time doing extensive interaction. It proved quite
stable in our production environment.
This patch:
Add generic functionnality to w1_io for Resume Command [A5h] lots of
slaves support.
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>
The search/pullup/add/remove device attributes were 0666 which would allow
arbitrary users to affect the 1 wire bus. Change to 0664 to prevent that.
I found this patch in the Android tree, apparently this has never been
sent upstream so doing it now.
Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.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 allows bin_attr->read,write,mmap callbacks to check file specific data
(such as inode owner) as part of any privilege validation.
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
Fix regression caused by commit 507e2fbaaa
("w1: w1 temp calculation overflow fix") whereby negative temperatures for
the DS18B20 are not converted properly.
When the temperature exceeds 32767 milli-degrees the temperature overflows
to -32768 millidegrees. These are both well within the -55 - +125 degree
range for the sensor.
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=12646
Signed-of-by: Ian Dall <ian@beware.dropbear.id.au>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Tested-by: Karsten Elfenbein <kelfe@gmx.de>
Cc: <stable@kernel.org>
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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (56 commits)
doc: fix typo in comment explaining rb_tree usage
Remove fs/ntfs/ChangeLog
doc: fix console doc typo
doc: cpuset: Update the cpuset flag file
Fix of spelling in arch/sparc/kernel/leon_kernel.c no longer needed
Remove drivers/parport/ChangeLog
Remove drivers/char/ChangeLog
doc: typo - Table 1-2 should refer to "status", not "statm"
tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in comments
No need to patch AMD-provided drivers/gpu/drm/radeon/atombios.h
devres/irq: Fix devm_irq_match comment
Remove reference to kthread_create_on_cpu
tree-wide: Assorted spelling fixes
tree-wide: fix 'lenght' typo in comments and code
drm/kms: fix spelling in error message
doc: capitalization and other minor fixes in pnp doc
devres: typo fix s/dev/devm/
Remove redundant trailing semicolons from macros
fix typo "definetly" -> "definitely" in comment
tree-wide: s/widht/width/g typo in comments
...
Fix trivial conflict in Documentation/laptops/00-INDEX
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>
Trivial patch which adds the __init/__exit macros to the module_init/
module_exit functions of
drivers/w1/w1.c
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
The connector documentation states that the argument to the callback
function is always a pointer to a struct cn_msg, but rather than encode it
in the API itself, it uses a void pointer everywhere. This doesn't make
much sense to encode the pointer in documentation as it prevents proper C
type checking from occurring and can easily allow people to use the wrong
pointer type. So convert the argument type to an explicit struct cn_msg
pointer.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.infradead.org/battery-2.6:
da9030_battery: Fix race between event handler and monitor
Add MAX17040 Fuel Gauge driver
w1: ds2760_battery: add support for sleep mode feature
w1: ds2760: add support for EEPROM read and write
ds2760_battery: cleanups in ds2760_battery_probe()
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 adds support for ds2760's sleep mode feature. With this feature
enabled, the chip enters a deep sleep mode and disconnects from the
battery when the w1 line is held down for more than 2 seconds.
This new behaviour can be switched on and off using a new module
parameter.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
Acked-by: Matt Reimer <mreimer@vpop.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
In order to modify the DS2762's status registers and to add support for
sleep mode, there is need for functions to write the internal EEPROM.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Matt Reimer <mreimer@vpop.net>
Acked-by: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
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>
This fixes a number of coding style issues I stubled over.
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 w1_ds2433 driver does not read from the hardware if the CRC was valid
on the last read. The validcrc flag should be cleared after a write so
that the new value can be read.
Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
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>
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12646
When the temperature exceeds 32767 milli-degrees the temperature overflows
to -32768 millidegrees. These are bothe well within the -55 - +125 degree
range for the sensor.
Fix overflow in left-shift of a u8.
Signed-off-by: Ian Dall <ian@beware.dropbear.id.au>
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Send completion status of the commands to the userspace. Message and
protocol are described in the documentation.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Paul Alfille <paul.alfille@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Command which allows to reset the bus.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Paul Alfille <paul.alfille@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This small patchset extendes existing commands with reset, master IO and
status messages. Reset is used to reset the bus for given master device,
master IO command allows to initiate IO against bus itself not selecting
slave device first, which can be used to probe the device for example.
And status messages carry command completion status back to the userspace
(namely very useful to get -ENODEV from when requested device was not
found).
Great thanks to Paul Alfille of OWFS for testing and commands suggestions.
This patch:
Allow starting of IO not against already found slave devices, but against
the bus itself, which can be used for example to probe devices.
[akpm@linux-foundation.org: reindent switch statements]
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Paul Alfille <paul.alfille@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Initiates search (or alarm search) and returns all found devices to
userspace. Found devices are not added into the system (i.e. they are
not attached to family devices or bus masters), it will be done via (if
was not done yet) usual timed searching.
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>
Writes and returns sampled data back to userspace.
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>
This patch series introduces and extends several userspace commands
used with netlink protocol.
Touch block command allows to write data and return sampled data to
the userspace.
Extended search and alarm seach commands to return list of slave
devices found during given search.
List masters command allows to send all registered master IDs to the
userspace.
Great thanks to Paul Alfille (owfs) who
tested this implementation and wrote w1-to-network daemon
http://sourceforge.net/projects/w1repeater/ and
Frederik Deweerdt and Randy Dunlap for review.
This patch:
Returns list of registered bus master devices.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Paul Alfille <paul.alfille@gmail.com>
Cc: Frederik Deweerdt <frederik.deweerdt@xprog.eu>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
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>
During test of the w1-gpio driver i found that in "w1.c:679
w1_slave_found()" the device id is converted to little-endian with
"cpu_to_le64()", but its not converted back to cpu format in "w1_io.c:293
w1_reset_select_slave()".
Based on a patch created by Andreas Hummel.
[akpm@linux-foundation.org: remove unneeded cast]
Reported-by: Andreas Hummel <andi_hummel@gmx.de>
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>
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>
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: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun's commit 7b595756ec 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: Parag 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[akpm@linux-foundation.org: minor fixlets and cleanups]
Signed-off-by: Bernhard Weirich <bernhard.weirich@riedel.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Ben Gardner <bgardner@wabtec.com>
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>
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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
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: 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>
Added strong pullup to thermal sensor driver and general documentation on
the sensor.
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 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: David Fries <david@fries.net>
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>
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: 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>
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: 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>
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: 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>
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: 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>
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: Jean Delvare <khali@linux-fr.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: Anton Vorontsov <cbouatmailru@gmail.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>
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: Anton Vorontsov <cbouatmailru@gmail.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>
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: Philipp Zabel <philipp.zabel@gmail.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Acked-by: Matt Reimer <mreimer@vpop.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: 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>
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: David Fries <david@fries.net>
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>
Remvoe variable which actually is not used (except assigning it a value)
and confusing break out of the family checking loop. Found by Harry Mason.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Harry J Mason <hjm03r@ecs.soton.ac.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The extra rom[0] check is flagging valid temperatures as invalid when
there is already a CRC data transmission check.
w1_therm_read_bin()
if (rom[8] == crc && rom[0])
verdict = 1;
Requiring rom[0] to be non-zero will flag as invalid temperature
conversions when the low byte is zero, specifically the temperatures 0C,
16C, 32C, 48C, -16C, -32C, and -48C.
The CRC check is produced on the device for the previous 8 bytes and is
required to ensure the data integrity in transmission. I don't see why the
extra check for rom[0] being non-zero is in there. Evgeniy Polyakov didn't
know either. Just for a check I unplugged the sensor, executed a
temperature conversion, and read the results. The read was all ff's, which
also failed the CRC, so it doesn't need to protect against a disconnected
sensor.
I have more extensive patches in the work, but these two trivial ones will
do for today. I would like to hear from people who use the ds2490 USB to
one wire dongle. 1 if you would be willing to test the patches as I
currently only have the one sensor on a short parisite powered wire, 2 if
there is any cheap sources for the ds2490.
Signed-off-by: David Fries <david@fries.net>
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>
Jean-François Dagenais