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path: root/drivers/w1/slaves/w1_therm.c
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2023-05-08w1: therm: constify pointers to hwmon_channel_infoKrzysztof Kozlowski1-1/+1
Statically allocated array of pointed to hwmon_channel_info can be made const for safety. Link: https://lore.kernel.org/r/20230407150121.79887-1-krzysztof.kozlowski@linaro.org Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2023-05-08w1: w1_therm: fix typo in commentJulia Lawall1-1/+1
Spelling mistake (triple letters) in comment. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/20220521111145.81697-6-Julia.Lawall@inria.fr Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2023-05-08w1: w1_therm: Use max() instead of doing it manuallyHaowen Bai1-1/+1
Fix following coccicheck warning: drivers/w1/slaves/w1_therm.c:1452:18-19: WARNING opportunity for max() Signed-off-by: Haowen Bai <baihaowen@meizu.com> Link: https://lore.kernel.org/r/1646908169-8050-1-git-send-email-baihaowen@meizu.com Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2023-05-08w1: w1_therm: fix locking behavior in convert_tStefan Wahren1-17/+14
The commit 67b392f7b8ed ("w1_therm: optimizing temperature read timings") accidentially inverted the logic for lock handling of the bus mutex. Before: pullup -> release lock before sleep no pullup -> release lock after sleep After: pullup -> release lock after sleep no pullup -> release lock before sleep This cause spurious measurements of 85 degree (powerup value) on the Tarragon board with connected 1-w temperature sensor (w1_therm.w1_strong_pull=0). In the meantime a new feature for polling the conversion completion has been integrated in these branches with commit 021da53e65fd ("w1: w1_therm: Add sysfs entries to control conversion time and driver features"). But this feature isn't available for parasite power mode, so handle this separately. Link: https://lore.kernel.org/regressions/2023042645-attentive-amends-7b0b@gregkh/T/ Fixes: 67b392f7b8ed ("w1_therm: optimizing temperature read timings") Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Link: https://lore.kernel.org/r/20230427112152.12313-1-stefan.wahren@i2se.com Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2022-03-18w1: w1_therm: Add support for Maxim MAX31850 thermoelement IF.Markus Reichl1-2/+68
MAX31850 shares family number 0x3B with DS1825. The device is generally compatible with DS1825 but needs a different temperature readout. It operates always in 14 bit mode and has all 4 higher bits of the Config register set to 1. Conversion time is 100ms. Signed-off-by: Markus Reichl <m.reichl@fivetechno.de> Link: https://lore.kernel.org/r/20220306145817.8753-1-m.reichl@fivetechno.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-25w1: w1_therm: fixes w1_seq for ds28ea00 sensorsLucas Denefle1-2/+6
w1_seq was failing due to several devices responding to the CHAIN_DONE at the same time. Now properly selects the current device in the chain with MATCH_ROM. Also acknowledgment was read twice. Signed-off-by: Lucas Denefle <lucas.denefle@converge.io> Link: https://lore.kernel.org/r/20220223113558.232750-1-lucas.denefle@converge.io Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-21w1: w1_therm: use swap() to make code cleanerYang Guang1-4/+3
Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid opencoding it. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: David Yang <davidcomponentone@gmail.com> Signed-off-by: Yang Guang <yang.guang5@zte.com.cn> Link: https://lore.kernel.org/r/cb14f9e6e86cf8494ed2ddce6eec8ebd988908d9.1640077704.git.yang.guang5@zte.com.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21w1: w1_therm: fix build warning in w1_seq_show()Yang Yingliang1-2/+1
Fix the following build warning: drivers/w1/slaves/w1_therm.c: In function ‘w1_seq_show’: drivers/w1/slaves/w1_therm.c:2059:6: warning: variable ‘rv’ set but not used [-Wunused-but-set-variable] int rv; ^~ Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20210518050415.615783-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21w1: w1_therm: correct function name bulk_read_support()Yang Yingliang1-1/+1
Fix the following make W=1 kernel build warning: drivers/w1/slaves/w1_therm.c:843: warning: expecting prototype for support_bulk_read(). Prototype was for bulk_read_support() instead Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20210518050401.615648-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24w1: slaves: Typo fixesBhaskar Chowdhury1-2/+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>
2021-03-24w1: w1_therm: use clamp() in int_to_short()Dan Carpenter1-2/+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>
2021-01-27w1: w1_therm: Fix conversion result for negative temperaturesIvan Zaentsev1-13/+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>
2020-11-12w1: w1_therm: Rename conflicting sysfs attribute 'eeprom' to 'eeprom_cmd'Ivan Zaentsev1-6/+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>
2020-10-05w1: w1_therm: make w1_poll_completion staticGreg Kroah-Hartman1-1/+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>
2020-10-05w1: Constify static w1_family_ops structsRikard Falkeborn1-3/+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>
2020-10-02w1: w1_therm: Add support for GXCAS GX20MH01 device.Ivan Zaentsev1-28/+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>
2020-10-02w1: w1_therm: Add sysfs entries to control conversion time and driver featuresIvan Zaentsev1-26/+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>
2020-05-21w1_therm: remove redundant assignments to variable retColin Ian King1-4/+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>
2020-05-21w1_therm: Free the correct variableDan Carpenter1-2/+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>
2020-05-15w1_therm: adding bulk read support to trigger multiple conversion on busAkira Shimahara1-2/+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>
2020-05-15w1_therm: adding alarm sysfs entryAkira Shimahara1-0/+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>
2020-05-15w1_therm: optimizing temperature read timingsAkira Shimahara1-101/+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>
2020-05-15w1_therm: adding eeprom sysfs entryAkira Shimahara1-57/+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>
2020-05-15w1_therm: adding resolution sysfs entryAkira Shimahara1-98/+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>
2020-05-15w1_therm: adding ext_power sysfs entryAkira Shimahara1-0/+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>
2020-05-15w1_therm: fix reset_select_slave during discoveryAkira Shimahara1-7/+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>
2020-05-15w1_therm: adding code comments and code reorderingAkira Shimahara1-168/+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>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 147Thomas Gleixner1-15/+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>
2017-11-08w1: keep balance of mutex locks and refcntsAlexey Khoroshilov1-28/+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>
2017-08-31drivers: w1: add hwmon temp support for w1_thermJaghathiswari Rankappagounder Natarajan1-0/+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>
2017-08-31drivers: w1: refactor w1_slave_show to make the temp reading functionality ↵Jaghathiswari Rankappagounder Natarajan1-31/+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>
2017-06-09w1: Add subsystem kernel public interfaceAndrew F. Davis1-3/+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>
2017-05-25w1: Organize driver source to natural/common orderAndrew F. Davis1-9/+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>
2016-08-31drivers: w1: style corrections-pointers-blanklines-comparisonsBen Werbowyj1-2/+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>
2016-08-31drivers: w1: removed assignment from within if statementBen Werbowyj1-2/+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>
2016-08-31drivers: w1: style corrections for parenthesis and bracesBen Werbowyj1-6/+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>
2016-05-02w1: add ability to set (SRAM) and store (EEPROM) configuration for temp ↵Ben Sen1-7/+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>
2015-06-13w1: use correct lock on error in w1_seq_show()Dan Carpenter1-2/+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>
2015-06-13w1: fix for loop exit condition in w1_seq_show()Dan Carpenter1-1/+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>
2015-05-24w1: Add support for DS28EA00 sequence to w1-thermMatt Campbell1-1/+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>
2015-05-24w1_therm reference count family dataDavid Fries1-15/+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>
2014-02-08w1: use family_data instead of rom in w1_slaveDavid Fries1-2/+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>
2013-08-22w1: slaves: w1_therm: convert to use w1_family_ops.groupsGreg Kroah-Hartman1-15/+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>
2013-06-04w1: add family based automatic module loadingAlexander Stein1-0/+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>
2013-02-19w1: w1_therm: Add force-pullup option for "broken" sensorsMichael Arndt1-1/+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>
2013-01-16w1_therm: Retries: remove old code add CRCDavid Stevenson1-19/+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>
2012-08-161-Wire: Add support for the maxim ds1825 temperature sensorRaphael Assenat1-0/+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>
2012-06-14W1: split master mutex to avoid deadlocks.NeilBrown1-5/+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>
2011-11-17W1: w1_therm: release the bus during conversion on externally powered devicesMaciej Szmigiero1-5/+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>
2011-08-26MAINTAINERS: Evgeniy has movedEvgeniy Polyakov1-2/+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>