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[PATCH 1/4] Documentation: w1_therm: clearly state about binary value for precision

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  [PATCH 1/4] Documentation: w1_therm: clearly state about binary value for precision Mariusz Bialonczyk <manio@skyboo.net> - 2017-02-16 10:30 +0100
    [PATCH 2/4] w1: add missing DS2413 documentation Mariusz Bialonczyk <manio@skyboo.net> - 2017-02-16 10:30 +0100
    [PATCH 4/4] w1: add documentation for w1_ds2438 Mariusz Bialonczyk <manio@skyboo.net> - 2017-02-16 10:30 +0100
    Re: [PATCH 1/4] Documentation: w1_therm: clearly state about binary  value for precision Mariusz Bialonczyk <manio@skyboo.net> - 2017-02-17 10:00 +0100

#1582410 — [PATCH 1/4] Documentation: w1_therm: clearly state about binary value for precision

Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
---
 Documentation/w1/slaves/w1_therm | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm
index d1f93af..e10cd91 100644
--- a/Documentation/w1/slaves/w1_therm
+++ b/Documentation/w1/slaves/w1_therm
@@ -42,6 +42,7 @@ SRAM, so it is reset when the sensor gets power-cycled.
 To store the current precision configuration into EEPROM, the value 0
 has to be written to the sysfs w1_slave file. Since the EEPROM has a limited
 amount of writes (>50k), this command should be used wisely.
+Note: this precision value has to be a binary one-byte value, not ASCII.
 
 The module parameter strong_pullup can be set to 0 to disable the
 strong pullup, 1 to enable autodetection or 2 to force strong pullup.
-- 
2.9.3

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#1582412 — [PATCH 2/4] w1: add missing DS2413 documentation

Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
---
 Documentation/w1/slaves/00-INDEX  |  2 ++
 Documentation/w1/slaves/w1_ds2413 | 50 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 Documentation/w1/slaves/w1_ds2413

diff --git a/Documentation/w1/slaves/00-INDEX b/Documentation/w1/slaves/00-INDEX
index 6e18c70..cbcca1d 100644
--- a/Documentation/w1/slaves/00-INDEX
+++ b/Documentation/w1/slaves/00-INDEX
@@ -2,6 +2,8 @@
 	- This file
 w1_therm
 	- The Maxim/Dallas Semiconductor ds18*20 temperature sensor.
+w1_ds2413
+	- The Maxim/Dallas Semiconductor ds2413 dual channel addressable switch.
 w1_ds2423
 	- The Maxim/Dallas Semiconductor ds2423 counter device.
 w1_ds28e04
diff --git a/Documentation/w1/slaves/w1_ds2413 b/Documentation/w1/slaves/w1_ds2413
new file mode 100644
index 0000000..936263a
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds2413
@@ -0,0 +1,50 @@
+Kernel driver w1_ds2413
+=======================
+
+Supported chips:
+  * Maxim DS2413 1-Wire Dual Channel Addressable Switch
+
+supported family codes:
+        W1_FAMILY_DS2413        0x3A
+
+Author: Mariusz Bialonczyk <manio@skyboo.net>
+
+Description
+-----------
+
+The DS2413 chip has two open-drain outputs (PIO A and PIO B).
+Support is provided through the sysfs files "output" and "state".
+
+Reading state
+-------------
+The "state" file provides one-byte value which is in the same format as for
+the chip PIO_ACCESS_READ command (refer the datasheet for details):
+
+Bit 0:   PIOA Pin State
+Bit 1:   PIOA Output Latch State
+Bit 2:   PIOB Pin State
+Bit 3:   PIOB Output Latch State
+Bit 4-7: Complement of Bit 3 to Bit 0 (verified by the kernel module)
+
+This file is readonly.
+
+Writing output
+--------------
+You can set the PIO pins using the "output" file.
+It is writable, you can write one-byte value to this sysfs file.
+Similarly the byte format is the same as for the PIO_ACCESS_WRITE command:
+
+Bit 0:   PIOA
+Bit 1:   PIOB
+Bit 2-7: No matter (driver will set it to "1"s)
+
+
+The chip has some kind of basic protection against transmission errors.
+When reading the state, there is a four complement bits.
+The driver is checking this complement, and when it is wrong then it is
+returning I/O error.
+
+When writing output, the master must repeat the PIO Output Data byte in
+its inverted form and it is waiting for a confirmation.
+If the write is unsuccessful for three times, the write also returns
+I/O error.
-- 
2.9.3

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#1582413 — [PATCH 4/4] w1: add documentation for w1_ds2438

Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
---
 Documentation/w1/slaves/00-INDEX  |  2 ++
 Documentation/w1/slaves/w1_ds2438 | 63 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 Documentation/w1/slaves/w1_ds2438

diff --git a/Documentation/w1/slaves/00-INDEX b/Documentation/w1/slaves/00-INDEX
index cbcca1d..8d76718 100644
--- a/Documentation/w1/slaves/00-INDEX
+++ b/Documentation/w1/slaves/00-INDEX
@@ -6,5 +6,7 @@ w1_ds2413
 	- The Maxim/Dallas Semiconductor ds2413 dual channel addressable switch.
 w1_ds2423
 	- The Maxim/Dallas Semiconductor ds2423 counter device.
+w1_ds2438
+	- The Maxim/Dallas Semiconductor ds2438 smart battery monitor.
 w1_ds28e04
 	- The Maxim/Dallas Semiconductor ds28e04 eeprom.
diff --git a/Documentation/w1/slaves/w1_ds2438 b/Documentation/w1/slaves/w1_ds2438
new file mode 100644
index 0000000..b99f367
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds2438
@@ -0,0 +1,63 @@
+Kernel driver w1_ds2438
+=======================
+
+Supported chips:
+  * Maxim DS2438 Smart Battery Monitor
+
+supported family codes:
+        W1_FAMILY_DS2438        0x26
+
+Author: Mariusz Bialonczyk <manio@skyboo.net>
+
+Description
+-----------
+
+The DS2438 chip provides several functions that are desirable to carry in
+a battery pack. It also has a 40 bytes of nonvolatile EEPROM.
+Because the ability of temperature, current and voltage measurement, the chip
+is also often used in weather stations and applications such as: rain gauge,
+wind speed/direction measuring, humidity sensing, etc.
+
+Current support is provided through the following sysfs files (all files
+except "iad" are readonly):
+
+"iad"
+-----
+This file controls the 'Current A/D Control Bit' (IAD) in the
+Status/Configuration Register.
+Writing a zero value will clear the IAD bit and disables the current
+measurements.
+Writing value "1" is setting the IAD bit (enables the measurements).
+The IAD bit is enabled by default in the DS2438.
+
+When writing to sysfs file bits 2-7 are ignored, so it's safe to write ASCII.
+An I/O error is returned when there is a problem setting the new value.
+
+"page0"
+-------
+This file provides full 8 bytes of the chip Page 0 (00h).
+This page contains the most frequently accessed information of the DS2438.
+Internally when this file is read, the additional CRC byte is also obtained
+from the slave device. If it is correct, the 8 bytes page data are passed
+to userspace, otherwise an I/O error is returned.
+
+"temperature"
+-------------
+Opening and reading this file initiates the CONVERT_T (temperature conversion)
+command of the chip, afterwards the temperature is read from the device
+registers and provided as an ASCII decimal value.
+
+Important: The returned value has to be divided by 256 to get a real
+temperature in degrees Celsius.
+
+"vad", "vdd"
+------------
+Opening and reading this file initiates the CONVERT_V (voltage conversion)
+command of the chip.
+
+Depending on a sysfs filename a different input for the A/D will be selected:
+vad: general purpose A/D input (VAD)
+vdd: battery input (VDD)
+
+After the voltage conversion the value is returned as decimal ASCII.
+Note: The value is in mV, so to get a volts the value has to be divided by 10.
-- 
2.9.3

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#1583221 — Re: [PATCH 1/4] Documentation: w1_therm: clearly state about binary value for precision

On Thu, 16 Feb 2017 10:05:36 +0100
Mariusz Bialonczyk <manio@skyboo.net> wrote:

> Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
> ---
>  Documentation/w1/slaves/w1_therm | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm
> index d1f93af..e10cd91 100644
> --- a/Documentation/w1/slaves/w1_therm
> +++ b/Documentation/w1/slaves/w1_therm
> @@ -42,6 +42,7 @@ SRAM, so it is reset when the sensor gets power-cycled.
>  To store the current precision configuration into EEPROM, the value 0
>  has to be written to the sysfs w1_slave file. Since the EEPROM has a limited
>  amount of writes (>50k), this command should be used wisely.
> +Note: this precision value has to be a binary one-byte value, not ASCII.
>  
>  The module parameter strong_pullup can be set to 0 to disable the
>  strong pullup, 1 to enable autodetection or 2 to force strong pullup.
> -- 
> 2.9.3
> 

Please skip this single patch. I was wrong about it.
w1_slave_store is using kstrtoint() so it is currently ok.

regards,
-- 
Mariusz Białończyk | xmpp/e-mail: manio@skyboo.net
http://manio.skyboo.net | https://github.com/manio

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