Commit Graph

178 Commits

Author SHA1 Message Date
Krzysztof Kozlowski
0df2a5e99d w1: therm: constify pointers to hwmon_channel_info
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>
2023-05-08 12:16:38 +02:00
Colin Ian King
ee896c5bf2 w1: ds2438: remove redundant initialization of variable crc
Variable crc is being initialized with a value that is never read,
it is being re-assigned later on. The initialization is redundant
and can be removed.

Cleans up clang scan build warning:
warning: Value stored to 'crc' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220522194622.13277-1-colin.i.king@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2023-05-08 08:14:51 +02:00
Julia Lawall
7f25058c96 w1: w1_therm: fix typo in comment
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>
2023-05-08 08:14:51 +02:00
Haowen Bai
1aa75bf517 w1: w1_therm: Use max() instead of doing it manually
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>
2023-05-08 08:14:51 +02:00
Krzysztof Kozlowski
4f5a5badb4 w1: Fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /\t/' -i */Kconfig

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20191120133826.12964-1-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2023-05-08 08:14:50 +02:00
Stefan Wahren
dca5480ab7 w1: w1_therm: fix locking behavior in convert_t
The commit 67b392f7b8 ("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 021da53e65 ("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: 67b392f7b8 ("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>
2023-05-08 08:13:35 +02:00
Krzysztof Kozlowski
39bbfdacae w1: ds2433: do not use assignment in if condition
Assignments in if condition are less readable and error-prone.  Fixes
also checkpatch warning:

  ERROR: do not use assignment in if condition

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-7-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Krzysztof Kozlowski
921e0f2fb0 w1: use octal for file permissions
Improve code readability and checkpatch warnings:

  WARNING: Symbolic permissions 'S_IRUGO' are not preferred. Consider using octal permissions '0444'.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-6-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Krzysztof Kozlowski
ad9c36be1f w1: minor white-space and code style fixes
Correct several coding convention violations around white-spaces:

  ERROR: spaces required around that '=' (ctx:VxV)
  WARNING: Missing a blank line after declarations
  ERROR: "foo* bar" should be "foo *bar"
  ERROR: "(foo*)" should be "(foo *)"
  WARNING: Block comments use * on subsequent lines
  WARNING: Block comments use a trailing */ on a separate line
  WARNING: please, no space before tabs
  WARNING: Missing a blank line after declarations
  ERROR: open brace '{' following struct go on the same line
  ERROR: that open brace { should be on the previous line

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-4-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Krzysztof Kozlowski
a2809664ca w1: ds28e04: correct kerneldoc annotation
Correct kerneldoc comments (or drop annotation) to fix:

  w1_ds28e04.c:57: warning: This comment starts with '/**', but isn't a kernel-doc comment.
  w1_ds28e04.c:149: warning: This comment starts with '/**', but isn't a kernel-doc comment.

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Krzysztof Kozlowski
a866ce3b4f w1: ds2433: correct kerneldoc annotation
Correct kerneldoc comments (or drop annotation) to fix:

  w1_ds2433.c:46: warning: This comment starts with '/**', but isn't a kernel-doc comment.
  w1_ds2433.c:141: warning: This comment starts with '/**', but isn't a kernel-doc comment.

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Krzysztof Kozlowski
45c85d974f w1: ds2408: drop kerneldoc annotation
Drop kerneldoc annotation from comment which is not a kerneldoc to fix:

  w1_ds2408.c:210: warning: This comment starts with '/**', but isn't a kernel-doc comment

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230415104304.104134-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20 14:15:06 +02:00
Markus Reichl
6e07a33f97 w1: w1_therm: Add support for Maxim MAX31850 thermoelement IF.
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>
2022-03-18 14:07:09 +01:00
Lucas Denefle
41a92a89ee w1: w1_therm: fixes w1_seq for ds28ea00 sensors
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>
2022-02-25 11:54:38 +01:00
Yang Guang
e233897b1f w1: w1_therm: use swap() to make code cleaner
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>
2021-12-21 10:38:13 +01:00
Christophe Leroy
33dc3e3e99 w1: Misuse of get_user()/put_user() reported by sparse
sparse warnings: (new ones prefixed by >>)
>> drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected char [noderef] __user *_pu_addr @@     got char *buf @@
   drivers/w1/slaves/w1_ds28e04.c:342:13: sparse:     expected char [noderef] __user *_pu_addr
   drivers/w1/slaves/w1_ds28e04.c:342:13: sparse:     got char *buf
>> drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected char const [noderef] __user *_gu_addr @@     got char const *buf @@
   drivers/w1/slaves/w1_ds28e04.c:356:13: sparse:     expected char const [noderef] __user *_gu_addr
   drivers/w1/slaves/w1_ds28e04.c:356:13: sparse:     got char const *buf

The buffer buf is a failsafe buffer in kernel space, it's not user
memory hence doesn't deserve the use of get_user() or put_user().

Access 'buf' content directly.

Link: https://lore.kernel.org/lkml/202111190526.K5vb7NWC-lkp@intel.com/T/
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/d14ed8d71ad4372e6839ae427f91441d3ba0e94d.1637946316.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03 14:30:05 +01:00
Luiz Sampaio
c999fbbdcf w1: ds2438: support for writing to offset register
Added a sysfs entry to support writing to the offset register on page1.
This register is used to calibrate the chip canceling offset errors in the
current ADC. This means that, over time, reading the IAD register will not
return the correct current measurement, it will have an offset. Writing to
the offset register if the two's complement of the current register while
passing zero current to the load will calibrate the measurements. This
change was tested on real hardware and it was able to calibrate the chip
correctly.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-7-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:33 +02:00
Luiz Sampaio
fd6ec5d795 w1: ds2438: adding support for reading page1
Added a sysfs entry to support reading the page1 registers. This registers
contain Elapsed Time Meter (ETM) data, which shows for how long the chip is
on, as well as an Offset Register data, which can be used to calibrate the
current measurement of the chip.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-6-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:33 +02:00
Luiz Sampaio
1f5e7518f0 w1: ds2438: fixing bug that would always get page0
The purpose of the w1_ds2438_get_page function is to get the register
values at the page passed as the pageno parameter. However, the page0 was
hardcoded, such that the function always returned the page0 contents. Fixed
so that the function can retrieve any page.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-5-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:33 +02:00
Luiz Sampaio
67c6964228 w1: ds2438: changed sysfs macro for rw file
The iad sysfs file has permissions for read and write. Changed to the
recommended macro BIN_ATTR_RW.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-4-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:32 +02:00
Luiz Sampaio
c9f2713531 w1: ds2438: fixed if brackets coding style issue
Since there is only one statement inside the if clause, no brackets are
required.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-3-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:32 +02:00
Luiz Sampaio
ddb20bcf77 w1: ds2438: fixed a coding style issue
There is an if statement and, if the function goes into it, it returns. So,
the next else is not required.

Signed-off-by: Luiz Sampaio <sampaio.ime@gmail.com>
Link: https://lore.kernel.org/r/20210519223046.13798-2-sampaio.ime@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21 14:51:32 +02:00
Yang Yingliang
c6fa1a96db w1: w1_therm: fix build warning in w1_seq_show()
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>
2021-05-21 14:51:03 +02:00
Yang Yingliang
6a072b2e37 w1: w1_therm: correct function name bulk_read_support()
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>
2021-05-21 14:50:58 +02:00
Chen Huang
6c00365d53 w1: ds28e17: Use module_w1_family to simplify the code
module_w1_family() makes the code simpler by eliminating
boilerplate code.

Signed-off-by: Chen Huang <chenhuang5@huawei.com>
Link: https://lore.kernel.org/r/20210408130954.1158963-2-chenhuang5@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10 10:58:21 +02:00
Chen Huang
88adcd6610 w1: ds2805: Use module_w1_family to simplify the code
module_w1_family() makes the code simpler by eliminating
boilerplate code.

Signed-off-by: Chen Huang <chenhuang5@huawei.com>
Link: https://lore.kernel.org/r/20210408130954.1158963-1-chenhuang5@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10 10:58:21 +02:00
Bhaskar Chowdhury
d8da00e1a7 w1: slaves: Typo fixes
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>
2021-03-24 08:26:30 +01:00
dongjian
b0ebbaeee3 w1: Use kobj_to_dev()[RESEND]
Use kobj_to_dev() instead of open-coding it

Signed-off-by: dongjian <dongjian@yulong.com>
Link: https://lore.kernel.org/r/1615877987-32163-1-git-send-email-dj0227@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 08:26:30 +01:00
Dan Carpenter
199c4d0efe w1: w1_therm: use clamp() in int_to_short()
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>
2021-03-24 08:26:30 +01:00
Ivan Zaentsev
2f6055c26f w1: w1_therm: Fix conversion result for negative temperatures
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: 9ace0b4dab (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>
2021-01-27 14:59:16 +01:00
Ivan Zaentsev
439e8f6f1e w1: w1_therm: Rename conflicting sysfs attribute 'eeprom' to 'eeprom_cmd'
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>
2020-11-12 08:50:13 +01:00
Greg Kroah-Hartman
05dbb62853 w1: w1_therm: make w1_poll_completion static
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>
2020-10-05 14:49:24 +02:00
Rikard Falkeborn
57de2dfcab w1: Constify static w1_family_ops structs
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>
2020-10-05 13:21:49 +02:00
Ivan Zaentsev
9ace0b4dab w1: w1_therm: Add support for GXCAS GX20MH01 device.
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>
2020-10-02 11:49:54 +02:00
Ivan Zaentsev
021da53e65 w1: w1_therm: Add sysfs entries to control conversion time and driver features
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>
2020-10-02 11:49:50 +02:00
Colin Ian King
f37d13d52c w1_therm: remove redundant assignments to variable ret
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>
2020-05-21 10:58:51 +02:00
Dan Carpenter
e420637b81 w1_therm: Free the correct variable
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: e2c94d6f57 ("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>
2020-05-21 10:58:46 +02:00
Akira Shimahara
57c76221d5 w1_therm: adding bulk read support to trigger multiple conversion on bus
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>
2020-05-15 16:29:00 +02:00
Akira Shimahara
e2c94d6f57 w1_therm: adding alarm sysfs entry
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>
2020-05-15 16:29:00 +02:00
Akira Shimahara
67b392f7b8 w1_therm: optimizing temperature read timings
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>
2020-05-15 16:28:59 +02:00
Akira Shimahara
45d457a4cf w1_therm: adding eeprom sysfs entry
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>
2020-05-15 16:28:59 +02:00
Akira Shimahara
308bdb94de w1_therm: adding resolution sysfs entry
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>
2020-05-15 16:28:59 +02:00
Akira Shimahara
b7bb6ca17a w1_therm: adding ext_power sysfs entry
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>
2020-05-15 16:28:59 +02:00
Akira Shimahara
c8ad65f6fb w1_therm: fix reset_select_slave during discovery
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>
2020-05-15 16:28:58 +02:00
Akira Shimahara
92b8d27244 w1_therm: adding code comments and code reordering
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>
2020-05-15 16:28:58 +02:00
Angelo Dureghello
cafa1a5b22 w1: ds2430: fix eeprom size in driver description
Non functional fix, set Kb to b, to avoid any misundertanding.

Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com>
Link: https://lore.kernel.org/r/20200507195050.472483-1-angelo.dureghello@timesys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-15 16:25:20 +02:00
Angelo Dureghello
c6bf3842a3 w1: new driver. DS2430 chip
add support for ds2430, 1 page, 256bit (32bytes) eeprom
(family 0x14).

Tests done:

32 bytes dump:

x@y:~# hexdump -C -n 32 /sys/bus/w1/devices/14-00000158556e/eeprom
00000000  39 39 0a 00 00 36 0a ff  ff ff ff ff ff ff ff ff
00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
00000020

34 bytes dump: 32 only displayed

x@y:~# hexdump -C -n 34 /sys/bus/w1/devices/14-00000158556e/eeprom
00000000  39 39 0a 00 00 36 0a ff  ff ff ff ff ff ff ff ff
00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
00000020

pattern write:

x@y:~# echo 123456789 > /sys/bus/w1/devices/14-00000158556e/eeprom
x@y:~# hexdump -C -n 54 /sys/bus/w1/devices/14-00000158556e/eeprom
00000000  31 32 33 34 35 36 37 38  39 0a ff ff ff ff ff ff
00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
00000020

specific address 1-byte write

x@y:~# dd if=/dev/zero of=/sys/bus/w1/devices/14-00000158556e/eeprom \
		count=1 bs=1 seek=4
1+0 records in
1+0 records out
x@y:~# hexdump -C -n 54 /sys/bus/w1/devices/14-00000158556e/eeprom
00000000  31 32 33 34 00 36 37 38  39 0a ff ff ff ff ff ff
00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
00000020

writing binary block

x@y:~# cat dump-128bytes.bin > /sys/bus/w1/devices/14-00000158556e/eeprom
cat: write error: File too large

x@y:~# cat dump-32bytes.bin > /sys/bus/w1/devices/14-00000158556e/eeprom
x@y:~# hexdump -C -n 54 /sys/bus/w1/devices/14-00000158556e/eeprom
00000000  10 0b 5b ff ff ff ff ff  ff ff ff ff ff ff ff ff
00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff 40
00000020

Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com>
Link: https://lore.kernel.org/r/20191019204015.61474-1-angelo.dureghello@timesys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-14 13:06:33 +08:00
YueHaibing
b058b2552e w1: ds250x: Fix build error without CRC16
If CRC16 is not set, building will fails:

drivers/w1/slaves/w1_ds250x.o: In function `w1_ds2505_read_page':
w1_ds250x.c:(.text+0x82f): undefined reference to `crc16'
w1_ds250x.c:(.text+0x90a): undefined reference to `crc16'
w1_ds250x.c:(.text+0x91a): undefined reference to `crc16'

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 25ec8710d9 ("w1: add DS2501, DS2502, DS2505 EPROM device driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20190920060318.35020-1-yuehaibing@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-10 15:35:41 +02:00
Thomas Bogendoerfer
25ec8710d9 w1: add DS2501, DS2502, DS2505 EPROM device driver
Add a 1-Wire slave driver to support DS250x EPROM deivces. This
slave driver attaches the devices to the NVMEM subsystem for
an easy in-kernel usage.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Link: https://lore.kernel.org/r/20190831082623.15627-3-tbogendoerfer@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04 14:34:31 +02:00
Greg Kroah-Hartman
8083f3d788 Merge 5.2-rc6 into char-misc-next
We need the char-misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-23 09:23:33 +02:00