The ds28ec20 eeprom is (almost) backward compatible with the
ds2433. The only differences are:
- the eeprom size is now 2560 bytes instead of 512;
- the number of pages is now 80 (same page size as the ds2433: 256 bits);
- the programming time has increased from 5ms to 10ms;
This patch adds support for the ds28ec20 to the ds2433 driver. From
the datasheet: The DS28EC20 provides a high degree of backward
compatibility with the DS2433. Besides the different family codes, the
only protocol change that is required on an existing DS2433
implementation is a lengthening of the programming duration (tPROG)
from 5ms to 10ms.
dmesg now returns:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
instead of:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
w1_master_driver w1_bus_master1: Family 43 for 43.000000478756.e0 is not registered.
Test script writing/reading random data (CONFIG_W1_SLAVE_DS2433_CRC is
not set):
#!/bin/sh
EEPROM=/sys/bus/w1/devices/43-000000478756/eeprom
BINFILE1=/home/root/file1.bin
BINFILE2=/home/root/file2.bin
for BS in 1 2 3 4 8 16 32 64 128 256 512 1024 2560; do
dd if=/dev/random of=${BINFILE1} bs=${BS} count=1 status=none
dd if=${BINFILE1} of=${EEPROM} status=none
dd if=${EEPROM} of=${BINFILE2} bs=${BS} count=1 status=none
if ! cmp --silent ${BINFILE1} ${BINFILE2}; then
echo file1
hexdump ${BINFILE1}
echo file2
hexdump ${BINFILE2}
echo FAIL
exit 1
fi
echo "${BS} OK!"
done
Results:
# ./test.sh
1 OK!
2 OK!
3 OK!
4 OK!
8 OK!
16 OK!
32 OK!
64 OK!
128 OK!
256 OK!
512 OK!
1024 OK!
2560 OK!
Tests with CONFIG_W1_SLAVE_DS2433_CRC=y:
$ cat /proc/config.gz | gunzip | grep CONFIG_W1_SLAVE_DS2433
CONFIG_W1_SLAVE_DS2433=m
CONFIG_W1_SLAVE_DS2433_CRC=y
# create a 32 bytes block with a crc, i.e.:
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
# fill all 80 blocks
$ dd if=test.bin of=/sys/bus/w1/devices/43-000000478756/eeprom bs=32 count=80
# read back all blocks, i.e.:
$ hexdump -C /sys/bus/w1/devices/43-000000478756/eeprom
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000020 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000030 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
...
000009e0 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
000009f0 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000a00
Note: both memories (ds2433 and ds28ec20) have been tested with the
new driver.
Signed-off-by: Marc Ferland <marc.ferland@sonatest.com>
Co-developed-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Link: https://lore.kernel.org/r/20231218150230.1992448-6-marc.ferland@sonatest.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
The ds2433 driver uses the 'validcrc' variable to mark out which pages
have been successfully (crc is valid) retrieved from the eeprom and
placed in the internal 'memory' buffer (see CONFIG_W1_SLAVE_DS2433_CRC).
The current implementation assumes that the number of pages will never
go beyond 32 pages (bit field is a u32). This is fine for the ds2433
since it only has 16 pages.
On the ds28ec20 though, the number of pages increases to 80 which will
not fit on a single u32.
As a solution, I replaced the u32 variable with a standard bitmap and
set the number of bits to 32 which is the same size we had before.
Signed-off-by: Marc Ferland <marc.ferland@sonatest.com>
Link: https://lore.kernel.org/r/20231218150230.1992448-5-marc.ferland@sonatest.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Add a ds2433_config structure for parameters that are different
between the ds2433 and the ds28ec20. The goal is to reuse the same
code for both chips.
A pointer to this config structure is added to w1_f23_data and the
CONFIG_W1_SLAVE_DS2433_CRC ifdefs are adjusted since now both driver
configurations (with or without crc support) will make use of
w1_f23_data.
Also, the 'memory' buffer is now dynamically allocated based on the
size specififed in the config structure to help support memories of
different sizes.
Signed-off-by: Marc Ferland <marc.ferland@sonatest.com>
Link: https://lore.kernel.org/r/20231218150230.1992448-4-marc.ferland@sonatest.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Binding for fixed NVMEM cells defined directly as NVMEM device subnodes
has been deprecated. It has been replaced by the "fixed-layout" NVMEM
layout binding.
New syntax is meant to be clearer and should help avoiding imprecise
bindings.
NVMEM subsystem already supports the new binding. It should be a good
idea to limit support for old syntax to existing drivers that actually
support & use it (we can't break backward compatibility!). That way we
additionally encourage new bindings & drivers to ignore deprecated
binding.
It wasn't clear (to me) if rtc and w1 code actually uses old syntax
fixed cells. I enabled them to don't risk any breakage.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
[for meson-{efuse,mx-efuse}.c]
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
[for mtk-efuse.c, nvmem/core.c, nvmem-provider.h]
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
[MT8192, MT8195 Chromebooks]
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
[for microchip-otpc.c]
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
[SAMA7G5-EK]
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20231020105545.216052-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
