Re: [PATCH v7 3/3] iio:temperature: Add MAX31856 thermocouple support
On Tue, 26 Mar 2019 12:18:42 +0100
Patrick Havelange wrote:
> From: Paresh Chaudhary
>
> This patch adds support for Maxim MAX31856 thermocouple
> temperature sensor support.
>
> More information can be found in:
> https://www.maximintegrated.com/en/ds/MAX31856.pdf
>
> NOTE: Driver support only Comparator Mode.
>
> Signed-off-by: Paresh Chaudhary
> Signed-off-by: Matt Weber
> Signed-off-by: Patrick Havelange
Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.
Thanks,
Jonathan
> ---
> Changes
> v1 -> v2
> [Peter
> 1. Fixed all space & 'return' related comments
> 2. Removed 'sysfs_create_group' api because
> iio_device_register function is handling sysfs entry
> 3. Return -EIO if there is any fault
> 4. Added check for 'read_size' before spi read call
> 5. Removed license text from the source file
> 6. Added .o file in alphabetic order
> 7. Used #defines instead of magic bits
>
> v2 -> v3
> [Jonathan
> 1. Used bool for fault_oc and fault_ovuv
> 2. Changed 'max31856_read' function and use byte array to
> store registers value.
> 3. Used 'GENMASK' where required
> 4. Changed logic 'max31856_thermocouple_read' function. Used
> array to read registers value.
> 5. Used 'devm_iio_device_register' and removed 'max31856_remove'.
> 6. Fixed other cosmetic changes.
> 7. Added 'sysfs-bus-iio-temperature-max31856' file and updated
> 'MAINTAINERS' file.
>
> v3 -> v4
> [Jonathan
> 1. Removed unwanted logic
> 2. Updated code to handle return value of max31856_read call
> 3. Added devicetree id table
> 4. Removed one-shot support from driver as this support was not
> implemented with correct design.
>
> v4 -> v5
> [Patrick
> 1. Rename thermocouple type to maxim,thermocouple-type for DT entry
> 2. Don't cache values from the Fault Status Register
> 3. Simplify a bit max31856_init()
> 4. Use IIO_NO_MOD in switch case + default error case
> 5. Use dev_*() instead of pr_*()
> 6. Fix missing space in comments
> 7. Removed iio_info.driver_module assignment as no longer present
> 8. Don't keep read/write buffer into the internal driver struct
> 9. Updated kernel version, add missing space in documentation
>10. Updated (c) year
>11. Removed linux/init.h #include
>12. More use of BIT() macro
>13. Removed iio_chan_spec.address assignment as not used
>14. In max31856_thermocouple_read(), same switch case order as
> channels definition
>15. Refactor show_fault_*() functions
>16. Use u8 as register type in max31856_{read,write}()
>
> v5 -> v6
> [Patrick
> 1. Use generic thermocouple-type property
> 2. Fix doc for fault_ovuv entry
> 3. Add check for supported thermocouple-types in probe()
>
> v6 -> v7
> [Patrick
> 1. None
> ---
> .../sysfs-bus-iio-temperature-max31856| 24 ++
> drivers/iio/temperature/Kconfig | 10 +
> drivers/iio/temperature/Makefile | 1 +
> drivers/iio/temperature/max31856.c| 353 ++
> 4 files changed, 388 insertions(+)
> create mode 100644
> Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
> create mode 100644 drivers/iio/temperature/max31856.c
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
> b/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
> new file mode 100644
> index ..3b3509a3ef2f
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
> @@ -0,0 +1,24 @@
> +What:/sys/bus/iio/devices/iio:deviceX/fault_oc
> +KernelVersion: 5.1
> +Contact: linux-...@vger.kernel.org
> +Description:
> + Open-circuit fault. The detection of open-circuit faults,
> + such as those caused by broken thermocouple wires.
> + Reading returns either '1' or '0'.
> + '1' = An open circuit such as broken thermocouple wires
> + has been detected.
> + '0' = No open circuit or broken thermocouple wires are detected
> +
> +What:/sys/bus/iio/devices/iio:deviceX/fault_ovuv
> +KernelVersion: 5.1
> +Contact: linux-...@vger.kernel.org
> +Description:
> + Overvoltage or Undervoltage Input Fault. The internal circuitry
> + is protected from excessive voltages applied to the thermocouple
> + cables by integrated MOSFETs at the T+ and T- inputs, and the
> + BIAS output. These MOSFETs turn off when the input voltage is
> + negative or greater than VDD.
> + Reading returns either '1' or '0'.
> + '1' = The input voltage is negative or greater than VDD.
> + '0' = The input voltage is positive and less than VDD
[PATCH v7 3/3] iio:temperature: Add MAX31856 thermocouple support
From: Paresh Chaudhary
This patch adds support for Maxim MAX31856 thermocouple
temperature sensor support.
More information can be found in:
https://www.maximintegrated.com/en/ds/MAX31856.pdf
NOTE: Driver support only Comparator Mode.
Signed-off-by: Paresh Chaudhary
Signed-off-by: Matt Weber
Signed-off-by: Patrick Havelange
---
Changes
v1 -> v2
[Peter
1. Fixed all space & 'return' related comments
2. Removed 'sysfs_create_group' api because
iio_device_register function is handling sysfs entry
3. Return -EIO if there is any fault
4. Added check for 'read_size' before spi read call
5. Removed license text from the source file
6. Added .o file in alphabetic order
7. Used #defines instead of magic bits
v2 -> v3
[Jonathan
1. Used bool for fault_oc and fault_ovuv
2. Changed 'max31856_read' function and use byte array to
store registers value.
3. Used 'GENMASK' where required
4. Changed logic 'max31856_thermocouple_read' function. Used
array to read registers value.
5. Used 'devm_iio_device_register' and removed 'max31856_remove'.
6. Fixed other cosmetic changes.
7. Added 'sysfs-bus-iio-temperature-max31856' file and updated
'MAINTAINERS' file.
v3 -> v4
[Jonathan
1. Removed unwanted logic
2. Updated code to handle return value of max31856_read call
3. Added devicetree id table
4. Removed one-shot support from driver as this support was not
implemented with correct design.
v4 -> v5
[Patrick
1. Rename thermocouple type to maxim,thermocouple-type for DT entry
2. Don't cache values from the Fault Status Register
3. Simplify a bit max31856_init()
4. Use IIO_NO_MOD in switch case + default error case
5. Use dev_*() instead of pr_*()
6. Fix missing space in comments
7. Removed iio_info.driver_module assignment as no longer present
8. Don't keep read/write buffer into the internal driver struct
9. Updated kernel version, add missing space in documentation
10. Updated (c) year
11. Removed linux/init.h #include
12. More use of BIT() macro
13. Removed iio_chan_spec.address assignment as not used
14. In max31856_thermocouple_read(), same switch case order as
channels definition
15. Refactor show_fault_*() functions
16. Use u8 as register type in max31856_{read,write}()
v5 -> v6
[Patrick
1. Use generic thermocouple-type property
2. Fix doc for fault_ovuv entry
3. Add check for supported thermocouple-types in probe()
v6 -> v7
[Patrick
1. None
---
.../sysfs-bus-iio-temperature-max31856| 24 ++
drivers/iio/temperature/Kconfig | 10 +
drivers/iio/temperature/Makefile | 1 +
drivers/iio/temperature/max31856.c| 353 ++
4 files changed, 388 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
create mode 100644 drivers/iio/temperature/max31856.c
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
b/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
new file mode 100644
index ..3b3509a3ef2f
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-temperature-max31856
@@ -0,0 +1,24 @@
+What: /sys/bus/iio/devices/iio:deviceX/fault_oc
+KernelVersion: 5.1
+Contact: linux-...@vger.kernel.org
+Description:
+ Open-circuit fault. The detection of open-circuit faults,
+ such as those caused by broken thermocouple wires.
+ Reading returns either '1' or '0'.
+ '1' = An open circuit such as broken thermocouple wires
+ has been detected.
+ '0' = No open circuit or broken thermocouple wires are detected
+
+What: /sys/bus/iio/devices/iio:deviceX/fault_ovuv
+KernelVersion: 5.1
+Contact: linux-...@vger.kernel.org
+Description:
+ Overvoltage or Undervoltage Input Fault. The internal circuitry
+ is protected from excessive voltages applied to the thermocouple
+ cables by integrated MOSFETs at the T+ and T- inputs, and the
+ BIAS output. These MOSFETs turn off when the input voltage is
+ negative or greater than VDD.
+ Reading returns either '1' or '0'.
+ '1' = The input voltage is negative or greater than VDD.
+ '0' = The input voltage is positive and less than VDD (normal
+ state).
diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig
index 82e4a62745e2..c66eeb23615b 100644
--- a/drivers/iio/temperature/Kconfig
+++ b/drivers/iio/temperature/Kconfig
@@ -97,4 +97,14 @@ config TSYS02D
This driver can also be built as a module. If so, the module will
