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* w1: Disable irqs during 1-wire bus operations, extend 1-wire reset pulseMarkus Franke2012-04-111-4/+18
| | | | | | | | | | | | | | This patch offers the possibility to disables irqs during w1_write_bit() and w1_reset_bus() operations as timing requirements are very strict for the 1-wire bus protocol. Per default interrupts are enabled but can be disabled via the module parameter "w1_disable_irqs". Extend 1-wire reset pulse length from 480us to 500us as 480us is the minimum requirement for the 1-wire reset/presence pulse. Signed-off-by: Markus Franke <franm@hrz.tu-chemnitz.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: disable irqs in critical sectionJan Weitzel2011-11-021-0/+5
| | | | | | | | | | | | Interrupting w1_delay() in w1_read_bit() results in missing the low level on the w1 line and receiving "1" instead of "0". Add local_irq_save()/local_irq_restore() around the critical section Signed-off-by: Jan Weitzel <j.weitzel@phytec.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* MAINTAINERS: Evgeniy has movedEvgeniy Polyakov2011-08-251-1/+1
| | | | | | 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>
* w1: add 1-wire (w1) reset and resume command API supportJean-François Dagenais2011-05-261-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* w1: coding style cleanups in w1_io.cDaniel Mack2009-04-021-8/+8
| | | | | | | | | 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>
* w1: add touch block commandEvgeniy Polyakov2009-01-081-1/+25
| | | | | | | | 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>
* w1: fix slave selection on big-endian systemsEvgeniy Polyakov2008-12-231-1/+3
| | | | | | | | | | | | | | | 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>
* w1: export w1_read_8 functionMadhusudhan Chikkature2008-11-121-1/+2
| | | | | | | | | | | 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>
* W1: w1_io.c reset comments and msleepDavid Fries2008-10-161-1/+13
| | | | | | | | | | | | | 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>
* W1: feature, enable hardware strong pullupDavid Fries2008-10-161-4/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* W1: fix deadlocks and remove w1_control_threadDavid Fries2008-10-161-1/+2
| | | | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] W1: possible cleanupsEvgeniy Polyakov2006-06-221-3/+3
| | | | | | | | | | | | | | | | | | | | | This patch contains the following possible cleanups: - the following file did't #include the header with the prototypes for it's global functions: - w1_int.c - #if 0 the following unused global function: - w1_family.c: w1_family_get() - make the following needlessly global functions static: - w1_family.c: __w1_family_put() - w1_io.c: w1_delay() - w1_io.c: w1_touch_bit() - w1_io.c: w1_read_8() - remove the following unused EXPORT_SYMBOL's: - w1_family.c: w1_family_put - w1_family.c: w1_family_registered Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1 exportsAndrew Morton2006-06-221-2/+7
| | | | | | | | | | | | | | | | | From: Andrew Morton <akpm@osdl.org> WARNING: "w1_read_block" [drivers/w1/slaves/w1_therm.ko] undefined! WARNING: "w1_write_8" [drivers/w1/slaves/w1_therm.ko] undefined! WARNING: "w1_reset_select_slave" [drivers/w1/slaves/w1_therm.ko] undefined! WARNING: "w1_reset_bus" [drivers/w1/slaves/w1_ds2433.ko] undefined! WARNING: "w1_write_8" [drivers/w1/slaves/w1_ds2433.ko] undefined! WARNING: "w1_read_block" [drivers/w1/slaves/w1_ds2433.ko] undefined! WARNING: "w1_write_block" [drivers/w1/slaves/w1_ds2433.ko] undefined! WARNING: "w1_reset_select_slave" [drivers/w1/slaves/w1_ds2433.ko] undefined! Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: Userspace communication protocol over connector.Evgeniy Polyakov2006-06-221-14/+4
| | | | | | | | | | | There are three types of messages between w1 core and userspace: 1. Events. They are generated each time new master or slave device found either due to automatic or requested search. 2. Userspace commands. Includes read/write and search/alarm search comamnds. 3. Replies to userspace commands. From: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: misc cleanupsAdrian Bunk2006-03-231-1/+1
| | | | | | | | | | | | This patch contains the following cleanups: - make needlessly global code static - declarations for global code belong into header files - w1.c: #if 0 the unused struct w1_slave_device Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: Added w1_reset_select_slave() - Resets the bus and then selects ↵Evgeniy Polyakov2005-09-081-0/+24
| | | | | | | | | | | the slave by sending either a skip rom or a rom match. Patch from Ben Gardner <bgardner@wabtec.com> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: Added the triplet w1 master method and changes w1_search() to ↵Evgeniy Polyakov2005-06-211-1/+42
| | | | | | | | | | use it. Adds the triplet w1 master method and changes w1_search() to use it. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: Cleans up usage of touch_bit/w1_read_bit/w1_write_bit.Evgeniy Polyakov2005-06-211-9/+61
| | | | | | | | Cleans up usage of touch_bit/w1_read_bit/w1_write_bit. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] w1: cleanups.Evgeniy Polyakov2005-06-211-2/+2
| | | | | | | | | | | | | - white space changes. - list_for_each_entry/list_for_each_entry_safe and reverse changes. - small coding style changes. - removed redundant NULL checks. - use attribute group and macros instead of direct device attributes. Patch is havily based on work from Adrian Bunk and Dmitry Torokhov, thanks guys. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+195
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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