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* w1: slaves: Typo fixesBhaskar Chowdhury2021-03-241-2/+2
| | | | | | | | | s/mesured/measured/ .......twice Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Link: https://lore.kernel.org/r/20210319052554.966-1-unixbhaskar@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: use clamp() in int_to_short()Dan Carpenter2021-03-241-2/+1
| | | | | | | | | It's slightly cleaner to use the clamp() macro instead of open coding this. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/YEedHNwqEH8fvjkD@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: Fix conversion result for negative temperaturesIvan Zaentsev2021-01-271-13/+9
| | | | | | | | | | | | | | DS18B20 device driver returns an incorrect value for negative temperatures due to a missing sign-extension in w1_DS18B20_convert_temp(). Fix by using s16 temperature value when converting to int. Fixes: 9ace0b4dab1c (w1: w1_therm: Add support for GXCAS GX20MH01 device.) Cc: stable <stable@vger.kernel.org> Reported-by: Paweł Marciniak <sunwire@gmail.com> Signed-off-by: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru> Link: https://lore.kernel.org/r/20210121093021.224764-1-ivan.zaentsev@wirenboard.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: Rename conflicting sysfs attribute 'eeprom' to 'eeprom_cmd'Ivan Zaentsev2020-11-121-6/+6
| | | | | | | | | | | | | | | | | | Duplicate attribute 'eeprom' is defined in: 1) Documentation/ABI/testing/sysfs-driver-w1_therm 2) Documentation/ABI/stable/sysfs-driver-w1_ds28e04 Both drivers define an attribute: /sys/bus/w1/devices/.../eeprom with conflicting behavior. Fix by renaming the newer one in w1_therm.c to 'eeprom_cmd'. Reported-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/lkml/20201029152845.6bbb39ce@coco.lan/ Signed-off-by: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru> Link: https://lore.kernel.org/r/20201112064931.8471-1-ivan.zaentsev@wirenboard.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: make w1_poll_completion staticGreg Kroah-Hartman2020-10-051-1/+1
| | | | | | | | | | kernel test robot rightly points out that w1_poll_completion() should be static, so mark it as such. Cc: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru> Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/r/20201005123703.GA800532@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: Constify static w1_family_ops structsRikard Falkeborn2020-10-051-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The only usage of these structs is to assign their address to the fops field in the w1_family struct, which is a const pointer. Make them const to allow the compiler to put them in read-only memory. This was done with the following Coccinelle semantic patch (http://coccinelle.lip6.fr/): // <smpl> @r1 disable optional_qualifier @ identifier i; position p; @@ static struct w1_family_ops i@p = {...}; @ok1@ identifier r1.i; position p; identifier s; @@ static struct w1_family s = { .fops=&i@p, }; @bad1@ position p!={r1.p,ok1.p}; identifier r1.i; @@ i@p @depends on !bad1 disable optional_qualifier@ identifier r1.i; @@ static +const struct w1_family_ops i={}; // </smpl> Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Link: https://lore.kernel.org/r/20201004193202.4044-3-rikard.falkeborn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: Add support for GXCAS GX20MH01 device.Ivan Zaentsev2020-10-021-28/+78
| | | | | | | | | | | | GX20MH01 device shares family number 0x28 with DS18B20. The device is generally compatible with DS18B20. Added are the lowest 2^-5, 2^-6 temperature bits in Config register; R2 bit in Config register enabling 13 and 14 bit resolutions. It is powered up in 14 bit mode. Signed-off-by: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru> Link: https://lore.kernel.org/r/20200904160004.87710-2-ivan.zaentsev@wirenboard.ru Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: Add sysfs entries to control conversion time and driver featuresIvan Zaentsev2020-10-021-26/+331
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The conversion time of common DS18B20 clones deviates from datasheet specs. Allow adjustment and automatic measure of the conversion time. Add 'conv_time' sysfs attribute: *read*: Current conversion time in milliseconds. *write*: '0': Set default conversion time. '1': Measure and set the conversion time. Make a single temperature conversion, poll and measure an actual value. Measured value is increased by 20% for temperature drift. A new conversion time is returned by reading the same attribute. other positive value: Set the conversion time in milliseconds. The setting is active until a resolution change. Then it is reset to default conversion time for a new resolution. Add 'features' sysfs attribute to control optional driver settings per device. Bit masks to read/write (logical OR): 1: Enable check for conversion success. If byte 6 of scratchpad memory is 0xC after conversion, and temperature reads 85.00 (powerup value) or 127.94 (insufficient power) - return a conversion error. 2: Enable poll for conversion completion. Generate read cycles after the conversion start and wait for 1's. In parasite power mode this feature is not available. There are some clones of DS18B20 with fixed 12 bit resolution. Make the driver verify the resolution by reading back the device after resolution change. Signed-off-by: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Link: https://lore.kernel.org/r/20200904160004.87710-1-ivan.zaentsev@wirenboard.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: remove redundant assignments to variable retColin Ian King2020-05-211-4/+4
| | | | | | | | | | | The variable ret is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20200519154553.873413-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: Free the correct variableDan Carpenter2020-05-211-2/+3
| | | | | | | | | | | The problem is that we change "p_args" to point to the middle of the string so when we free it at the end of the function it's not freeing the same pointer that we originally allocated. Fixes: e2c94d6f5720 ("w1_therm: adding alarm sysfs entry") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/20200520120019.GA172354@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding bulk read support to trigger multiple conversion on busAkira Shimahara2020-05-151-2/+249
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding bulk read support: Sending a 'trigger' command in the dedicated sysfs entry of bus master device send a conversion command for all the slaves on the bus. The sysfs entry is added as soon as at least one device supporting this feature is detected on the bus. The behavior of the sysfs reading temperature on the device is as follow: * If no bulk read pending, trigger a conversion on the device, wait for the conversion to be done, read the temperature in device RAM * If a bulk read has been trigger, access directly the device RAM This behavior is the same on the 2 sysfs entries ('temperature' and 'w1_slave'). Reading the therm_bulk_read sysfs give the status of bulk operations: * '-1': conversion in progress on at least 1 sensor * '1': conversion complete but at least one sensor has not been read yet * '0': no bulk operation. Reading temperature on ecah device will trigger a conversion As not all devices support bulk read feature, it has been added in device family structure. The attribute is set at master level as soon as a supporting device is discover. It is removed when the last supported device leave the bus. The count of supported device is kept with the static counter bulk_read_device_counter. A strong pull up is apply on the line if at least one device required it. The duration of the pull up is the max time required by a device on the line, which depends on the resolution settings of each device. The strong pull up could be adjust with the a module parameter. Updating documentation in Documentation/ABI/testing/sysfs-driver-w1_therm and Documentation/w1/slaves/w1_therm.rst accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203820.411483-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding alarm sysfs entryAkira Shimahara2020-05-151-0/+161
| | | | | | | | | | | | | | | | | | | | Adding device alarms settings by a dedicated sysfs entry alarms (RW): read or write TH and TL in the device RAM. Checking devices in alarm state could be performed using the master search command. As alarms temperature level are store in a 8 bit register on the device and are signed values, a safe cast shall be performed using the min and max temperature that device are able to measure. This is done by int_to_short inline function. A 'write_data' field is added in the device structure, to bind the correct writing function, as some devices may have 2 or 3 bytes RAM. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203801.411253-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: optimizing temperature read timingsAkira Shimahara2020-05-151-101/+185
| | | | | | | | | | | | | | | | | | | | | | | | | | Optimizing temperature reading by reducing waiting conversion time according to device resolution settings, as per device specification. This is device dependent as not all the devices supports resolution setting, so it has been added in device family structures. The process to read the temperature on the device has been adapted in a new function 'convert_t()', which replace the former 'read_therm()', is introduce to deal with this timing. Strong pull up is also applied during the required time, according to device power status needs and 'strong_pullup' module parameter. 'temperature_from_RAM()' function is introduced to get the correct temperature computation (device dependent) from device RAM data. An new sysfs entry has been added to ouptut only temperature. The old entry w1_slave has been kept for compatibility, without changing its output format. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203742.411039-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding eeprom sysfs entryAkira Shimahara2020-05-151-57/+118
| | | | | | | | | | | | | | | | | The driver implement 2 hardware functions to access device RAM: * copy_scratchpad * recall_scratchpad They act according to device specifications. As EEPROM operations are not device dependent (all w1_therm can perform EEPROM read/write operation following the same protocol), it is removed from device families structures. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203725.410844-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding resolution sysfs entryAkira Shimahara2020-05-151-98/+344
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding resolution sysfs entry (RW) to get or set the device resolution Write values are managed as follow: * '9..12': resolution to set in bit * Anything else: do nothing Read values are : * '9..12': device resolution in bit * '-xx': xx is kernel error when reading the resolution Only supported devices will show the sysfs entry. A new family has been created for DS18S20 devices as they do not implement resolution feature. The resolution of each device is check when the device is discover by the bus master, in 'w1_therm_add_slave(struct w1_slave *)'. The status is stored in the device structure w1_therm_family_data so that the driver always knows the resolution of each device, which could be used later to determine the required conversion duration (resolution dependent). The resolution is re evaluate each time a user read or write the sysfs entry. To avoid looping through the w1_therm_families at run time, the pointer 'specific_functions' is set up to the correct 'w1_therm_family_converter' when the slave is added (which mean when it is discovered by the master). This initialization is done by a helper function 'device_family(struct w1_slave *sl)', and a dedicated macro 'SLAVE_SPECIFIC_FUNC(sl)' allow the access to the specific function of the slave device. 'read_scratchpad' and 'write_scratchpad' are the hardware functions to access the device RAM, as per protocol specification. It cancel the former 'precision' functions, which was only set and never read (so not stored in the device struct). Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203708.410649-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding ext_power sysfs entryAkira Shimahara2020-05-151-0/+137
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding ext_power sysfs entry (RO). Return the power status of the device: - 0: device parasite powered - 1: device externally powered - xx: xx is kernel error The power status of each device is check when the device is discover by the bus master, in 'w1_therm_add_slave(struct w1_slave *)'. The status is stored in the device structure w1_therm_family_data so that the driver always knows the power state of each device, which could be used later to determine the required strong pull up to apply on the line. The power status is re evaluate each time the sysfs ext_power read by a user. The hardware function 'read_powermode(struct w1_slave *sl)' act just as per device specifications, sending W1_READ_PSUPPLY command on the bus, and issue a read time slot, reading only one bit. A helper function 'bool bus_mutex_lock(struct mutex *lock)' is introduced. It try to aquire the bus mutex several times (W1_THERM_MAX_TRY), waiting W1_THERM_RETRY_DELAY between two attempt. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203650.410439-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: fix reset_select_slave during discoveryAkira Shimahara2020-05-151-7/+41
| | | | | | | | | | | | | | | | | | | | | Fix reset_select_slave issue during devices discovery by the master on bus. The w1_reset_select_slave() from w1_io.c, which was previously used, assume that if the slave count is 1 there is only one slave attached on the bus. This is not always true. For example when discovering devices, when the first device is discover by the bus master, its slave count is 1, but some other slaves may be on the bus. In that case instead of adressing command to the attached slave the master throw a SKIP ROM command so that all slaves attached on the bus will answer simultenaously causing data collision. A dedicated reset_select_slave() function is implemented here, it always perform an adressing to each slave using the MATCH ROM command. Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203610.409975-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: adding code comments and code reorderingAkira Shimahara2020-05-151-168/+259
| | | | | | | | | | | | | | | Adding code comments to split code in dedicated parts. After the global declarations (defines, macros and function declarations), code is organized as follow : - Device and family dependent structures and functions - Interfaces functions - Helpers functions - Hardware functions - Sysfs interface functions Signed-off-by: Akira Shimahara <akira215corp@gmail.com> Link: https://lore.kernel.org/r/20200511203535.409599-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 147Thomas Gleixner2019-05-301-15/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the [therms] of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190524100844.941364072@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: keep balance of mutex locks and refcntsAlexey Khoroshilov2017-11-081-28/+31
| | | | | | | | | | | | | | | | w1_therm_eeprom() and w1_DS18B20_precision() decrement THERM_REFCNT on error paths, while they did not increment it yet. read_therm() unlocks bus mutex on some error paths, while it is not acquired. The patch makes sure all the functions keep the balance in usage of the mutex and the THERM_REFCNT. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: w1: add hwmon temp support for w1_thermJaghathiswari Rankappagounder Natarajan2017-08-311-0/+86
| | | | | | | | | This change adds hwmon temp support for w1_therm. Signed-off-by: Jaghathiswari Rankappagounder Natarajan <jaghu@google.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Acked-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: w1: refactor w1_slave_show to make the temp reading functionality ↵Jaghathiswari Rankappagounder Natarajan2017-08-311-31/+51
| | | | | | | | | | | | separate Inside the w1_slave_show function refactor the code to read the temp into a separate function. Signed-off-by: Jaghathiswari Rankappagounder Natarajan <jaghu@google.com> Acked-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: Add subsystem kernel public interfaceAndrew F. Davis2017-06-091-3/+7
| | | | | | | | | | | | | | | | | | | | Like other subsystems we should be able to define slave devices outside of the w1 directory. To do this we move public facing interface definitions to include/linux/w1.h and rename the internal definition file to w1_internal.h. As w1_family.h and w1_int.h contained almost entirely public driver interface definitions we simply removed these files and moved the remaining definitions into w1_internal.h. With this we can now start to move slave devices out of w1/slaves and into the subsystem based on the function they implement, again like other drivers. Signed-off-by: Andrew F. Davis <afd@ti.com> Reviewed-by: Sebastian Reichel <sre@kernel.org> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: Organize driver source to natural/common orderAndrew F. Davis2017-05-251-9/+9
| | | | | | | | | | | | | | | Structures and functions should be ordered such that forward declaration use is minimized. MODULE_* macros should immediately follow the structures and functions upon which they act. Remaining MODULE_* macros should be at the end of the file in alphabetical order. Signed-off-by: Andrew F. Davis <afd@ti.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: w1: style corrections-pointers-blanklines-comparisonsBen Werbowyj2016-08-311-2/+4
| | | | | | | | | | | | Correct pointer notations to include whitespace between variable type and "*" character. Inserted blank line after variable declatations at two locations. Rearranged comparison within an if statment to have the constant on the right-hand side. Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: w1: removed assignment from within if statementBen Werbowyj2016-08-311-2/+4
| | | | | | | | | Assignment of variable count removed from within an if statment. This was done at two locations in the file. Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: w1: style corrections for parenthesis and bracesBen Werbowyj2016-08-311-6/+4
| | | | | | | | | | Inserted whitespace between command and open parenthesis at two locations. Removed new line between open brace and command/declaration at two locations. Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: add ability to set (SRAM) and store (EEPROM) configuration for temp ↵Ben Sen2016-05-011-7/+211
| | | | | | | | | | | | | | sensors like DS18B20 Since many temperature sensors come "preconfigured" with a lower precision, people are stuck at that precision when running on a kernel based device (unlike the Dallas 1Wire library for e.g. Arduino, which supports writing the configuration/scratchpad). This patch adds write support for the scratchpad/precision registers via w1_slave sysfs. Signed-off-by: Ben Sen <0.x29a.0@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: use correct lock on error in w1_seq_show()Dan Carpenter2015-06-131-2/+2
| | | | | | | | | | | | | | | | | I noticed there was a problem here because Smatch complained: drivers/w1/slaves/w1_therm.c:416 w1_seq_show() warn: inconsistent returns 'mutex:&sl->master->mutex'. Locked on: line 416 Unlocked on: line 413 The problem is that we lock ->mutex but we unlock ->bus_mutex on error. David Fries says that ->bus_mutex is correct and ->mutex is incorrect. Fixes: d9411e57dc7f ('w1: Add support for DS28EA00 sequence to w1-therm') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: fix for loop exit condition in w1_seq_show()Dan Carpenter2015-06-131-1/+1
| | | | | | | | | The W1_42_FINISHED_BYTE is 0xFF so the cast means the condition is never true. Fixes: d9411e57dc7f ('w1: Add support for DS28EA00 sequence to w1-therm') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: Add support for DS28EA00 sequence to w1-thermMatt Campbell2015-05-241-1/+101
| | | | | | | | | | | | | | | This patch provides support for the DS28EA00 digital thermometer. The DS28EA00 provides an additional two pins for implementing a sequence detection algorithm. This feature allows you to determine the physical location of the chip in the 1-wire bus without needing pre-existing knowledge of the bus ordering. Support is provided through the sysfs w1_seq file. The file will contain a single line with an integer value representing the device index in the bus starting at 0. Signed-off-by: Matt Campbell <mattrcampbell@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm reference count family dataDavid Fries2015-05-241-15/+47
| | | | | | | | | | | | | | | | A temperature conversion can take 750 ms and when possible the w1_therm slave driver drops the bus_mutex to allow other bus operations, but that includes operations such as a periodic slave search, which can remove this slave when it is no longer detected. If that happens the sl->family_data will be freed and set to NULL causing w1_slave_show to crash when it wakes up. Signed-off-by: David Fries <David@Fries.net> Reported-By: Thorsten Bschorr <thorsten@bschorr.de> Tested-by: Thorsten Bschorr <thorsten@bschorr.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: use family_data instead of rom in w1_slaveDavid Fries2014-02-081-2/+19
| | | | | | | | | | | | | | The first line printed from w1_slave gives the context of the w1 device. So does the second line, but if the CRC check failed, the second line contains the last successful result. It is confusing when it prints the temperature next to the line that might be a previous conversion and has nothing to do with that printed temperature value. Modify the code to store the last good conversion in family_data, which is designed for custom data structures. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: slaves: w1_therm: convert to use w1_family_ops.groupsGreg Kroah-Hartman2013-08-221-15/+9
| | | | | | | | | | | This moves the sysfs file creation/removal to the w1 core by using the .groups field, saving code in the slave driver. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: David Stevenson <david@avoncliff.com> Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de> Cc: Michael Arndt <michael@scriptkiller.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: add family based automatic module loadingAlexander Stein2013-06-031-0/+5
| | | | | | | | | This patch allows the 1-wire bus to autoload the corresponding module for each slave being attached. This works similar to bluetooth protocols. Signed-off-by: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1: w1_therm: Add force-pullup option for "broken" sensorsMichael Arndt2013-02-181-1/+10
| | | | | | Signed-off-by: Michael Arndt <michael@scriptkiller.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* w1_therm: Retries: remove old code add CRCDavid Stevenson2013-01-161-19/+6
| | | | | | | | | | | | | w1_therm includes some obsolete code to detect bad_roms, this is no longer relevant. The retry code is only used for this bad_rom test, however there is a CRC check that detects a bad read, but does not trigger a retry. This patch removes all the bad_rom code and uses the CRC check to trigger retries. Signed-off-by: David Stevenson <david@avoncliff.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* 1-Wire: Add support for the maxim ds1825 temperature sensorRaphael Assenat2012-08-161-0/+9
| | | | | | | This patch adds support for maxim ds1825 based 1-wire temperature sensors. Signed-off-by: Raphael Assenat <raph@8d.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* W1: split master mutex to avoid deadlocks.NeilBrown2012-06-141-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'mutex' in struct w1_master is use for two very different purposes. Firstly it protects various data structures such as the list of all slaves. Secondly it protects the w1 buss against concurrent accesses. This can lead to deadlocks when the ->probe code called while adding a slave needs to talk on the bus, as is the case for power_supply devices. ds2780 and ds2781 drivers contain a work around to track which process hold the lock simply to avoid this deadlock. bq27000 doesn't have that work around and so deadlocks. There are other possible deadlocks involving sysfs. When removing a device the sysfs s_active lock is held, so the lock that protects the slave list must take precedence over s_active. However when access power_supply attributes via sysfs, the s_active lock must take precedence over the lock that protects accesses to the bus. So to avoid deadlocks between w1 slaves and sysfs, these must be two separate locks. Making them separate means that the work around in ds2780 and ds2781 can be removed. So this patch: - adds a new mutex: "bus_mutex" which serialises access to the bus. - takes in mutex in w1_search and ds1wm_search while they access the bus for searching. The mutex is dropped before calling the callback which adds the slave. - changes all slaves to use bus_mutex instead of mutex to protect access to the bus - removes w1_ds2790_io_nolock and w1_ds2781_io_nolock, and the related code from drivers/power/ds278[01]_battery.c which calls them. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* W1: w1_therm: release the bus during conversion on externally powered devicesMaciej Szmigiero2011-11-171-5/+31
| | | | | | | | | | | | | | | | | | | | | | | | w1_therm devices can either be bus powered or externally powered. When device is bus powered during temperature conversion the bus have to be left high to provide necessary power. Some masters also allow strong power-up to be enabled in this case. Naturally, no communication over bus can occur during that time. However, if device has external power then there is no such restriction, and host can talk to other devices during temperature conversion. There is command which allows us to check how device is powered, this patch uses it to release the bus on externally w1_therm powered devices during temperature conversion. Also, this changes uninterruptible sleeps there into interruptible ones to avoid long uninterruptible sleep if w1 subsystem happens to grab bus for scan during w1_therm_read(). Signed-off-by: Maciej Szmigiero <mhej@o2.pl> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* MAINTAINERS: Evgeniy has movedEvgeniy Polyakov2011-08-261-2/+2
| | | | | | 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>
* drivers/w1/slaves/w1_therm.c: add support for DS28EA00Christian Glindkamp2011-07-271-0/+9
| | | | | | | Signed-off-by: Christian Glindkamp <christian.glindkamp@taskit.de> 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: w1 temp: fix negative termperature calculationIan Dall2010-04-241-3/+2
| | | | | | | | | | | | | | | | | | | Fix regression caused by commit 507e2fbaaacb6f164b4125b87c5002f95143174b ("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>
* w1: w1 temp calculation overflow fixIan Dall2009-02-111-1/+1
| | | | | | | | | | | | | | | | 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>
* W1: w1_therm consistent mutex access code cleanupDavid Fries2008-10-161-1/+1
| | | | | | | | | | | 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>
* W1: w1_therm fix user buffer overflow and catDavid Fries2008-10-161-35/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* W1: feature, w1_therm.c use strong pullup and documentationDavid Fries2008-10-161-2/+13
| | | | | | | | | | 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>
* W1: w1_therm.c standardize units to millidegrees CDavid Fries2008-02-061-1/+2
| | | | | | | | | | | | | | | | | | | 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>
* W1: w1_therm.c is flagging 0C etc as invalidDavid Fries2008-01-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* W1: w1_therm.c ds18b20 decode freezing temperatures correctlyDavid Fries2008-01-221-1/+1
| | | | | | | | | | | | | | | | | | | | Correct the decoding of negative C temperatures. The code did a binary OR of two bytes to make a 16 bit value, but assignd it to an integer. This caused the value to not be sign extended and to loose that it was a negative number in the assignment. Before the patch (in my freezer), w1_slave ed fe 4b 46 7f ff 03 10 e4 : crc=e4 YES ed fe 4b 46 7f ff 03 10 e4 t=4078 With the patch, e3 fe 4b 46 7f ff 0d 10 81 : crc=81 YES e3 fe 4b 46 7f ff 0d 10 81 t=-17 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>