* [PATCH v6 1/4] dt-bindings: iio/temperature: Add thermocouple types @ 2019-03-07 10:34 Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange ` (2 more replies) 0 siblings, 3 replies; 8+ messages in thread From: Patrick Havelange @ 2019-03-07 10:34 UTC (permalink / raw) To: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree Cc: Patrick Havelange This patch introduces common thermocouple types used by various temperature sensors. Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> --- Changes v6 - Add this file --- .../dt-bindings/iio/temperature/thermocouple.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 include/dt-bindings/iio/temperature/thermocouple.h diff --git a/include/dt-bindings/iio/temperature/thermocouple.h b/include/dt-bindings/iio/temperature/thermocouple.h new file mode 100644 index 000000000000..ce037f5238ac --- /dev/null +++ b/include/dt-bindings/iio/temperature/thermocouple.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _DT_BINDINGS_TEMPERATURE_THERMOCOUPLE_H +#define _DT_BINDINGS_TEMPERATURE_THERMOCOUPLE_H + + +#define THERMOCOUPLE_TYPE_B 0x00 +#define THERMOCOUPLE_TYPE_E 0x01 +#define THERMOCOUPLE_TYPE_J 0x02 +#define THERMOCOUPLE_TYPE_K 0x03 +#define THERMOCOUPLE_TYPE_N 0x04 +#define THERMOCOUPLE_TYPE_R 0x05 +#define THERMOCOUPLE_TYPE_S 0x06 +#define THERMOCOUPLE_TYPE_T 0x07 + +#endif /* _DT_BINDINGS_TEMPERATURE_THERMOCOUPLE_H */ -- 2.19.1 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type 2019-03-07 10:34 [PATCH v6 1/4] dt-bindings: iio/temperature: Add thermocouple types Patrick Havelange @ 2019-03-07 10:34 ` Patrick Havelange 2019-03-10 9:50 ` Jonathan Cameron 2019-03-11 22:26 ` Rob Herring 2019-03-07 10:34 ` [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support Patrick Havelange 2 siblings, 2 replies; 8+ messages in thread From: Patrick Havelange @ 2019-03-07 10:34 UTC (permalink / raw) To: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree Cc: Patrick Havelange This explains the new generic property "thermocouple-type" that can be used with temperature sensors. Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> --- Changes v6 - Add this file --- .../bindings/iio/temperature/temperature-bindings.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt diff --git a/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt new file mode 100644 index 000000000000..69a6441d8083 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt @@ -0,0 +1,11 @@ +If the temperature sensor device can be configured to use some specific +thermocouple type, you can use the defined types provided in the file +"include/dt-bindings/iio/temperature/thermocouple.h". + +Optional property: +thermocouple-type: The type of the thermocouple used by the device. + +For example: + device { + thermocouple-type = <THERMOCOUPLE_TYPE_K> ; + }; -- 2.19.1 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange @ 2019-03-10 9:50 ` Jonathan Cameron 2019-03-11 22:26 ` Rob Herring 1 sibling, 0 replies; 8+ messages in thread From: Jonathan Cameron @ 2019-03-10 9:50 UTC (permalink / raw) To: Patrick Havelange Cc: Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree On Thu, 7 Mar 2019 11:34:07 +0100 Patrick Havelange <patrick.havelange@essensium.com> wrote: > This explains the new generic property "thermocouple-type" that > can be used with temperature sensors. > > Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> I'm happy with this, but want to allow time for Rob and other devicetree types to have a look at it as well. Give me a poke if this is looking unloved in a week or so. Thanks, Jonathan > --- > Changes v6 > - Add this file > --- > .../bindings/iio/temperature/temperature-bindings.txt | 11 +++++++++++ > 1 file changed, 11 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > > diff --git a/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > new file mode 100644 > index 000000000000..69a6441d8083 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > @@ -0,0 +1,11 @@ > +If the temperature sensor device can be configured to use some specific > +thermocouple type, you can use the defined types provided in the file > +"include/dt-bindings/iio/temperature/thermocouple.h". > + > +Optional property: > +thermocouple-type: The type of the thermocouple used by the device. > + > +For example: > + device { > + thermocouple-type = <THERMOCOUPLE_TYPE_K> ; > + }; ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange 2019-03-10 9:50 ` Jonathan Cameron @ 2019-03-11 22:26 ` Rob Herring 1 sibling, 0 replies; 8+ messages in thread From: Rob Herring @ 2019-03-11 22:26 UTC (permalink / raw) To: Patrick Havelange Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree On Thu, Mar 07, 2019 at 11:34:07AM +0100, Patrick Havelange wrote: > This explains the new generic property "thermocouple-type" that > can be used with temperature sensors. > > Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> > --- > Changes v6 > - Add this file > --- > .../bindings/iio/temperature/temperature-bindings.txt | 11 +++++++++++ > 1 file changed, 11 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > > diff --git a/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > new file mode 100644 > index 000000000000..69a6441d8083 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/temperature/temperature-bindings.txt > @@ -0,0 +1,11 @@ > +If the temperature sensor device can be configured to use some specific > +thermocouple type, you can use the defined types provided in the file > +"include/dt-bindings/iio/temperature/thermocouple.h". You can include patch 1 in this patch. > + > +Optional property: Optional or not is really up to the specific device. > +thermocouple-type: The type of the thermocouple used by the device. What's the type? "A single cell" presumably. > + > +For example: As this is example is incomplete, I'd drop this. > + device { > + thermocouple-type = <THERMOCOUPLE_TYPE_K> ; > + }; > -- > 2.19.1 > ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info 2019-03-07 10:34 [PATCH v6 1/4] dt-bindings: iio/temperature: Add thermocouple types Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange @ 2019-03-07 10:34 ` Patrick Havelange 2019-03-11 22:28 ` Rob Herring 2019-03-07 10:34 ` [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support Patrick Havelange 2 siblings, 1 reply; 8+ messages in thread From: Patrick Havelange @ 2019-03-07 10:34 UTC (permalink / raw) To: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree Cc: Patrick Havelange From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> This patch added device tree binding info for MAX31856 driver. Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> --- Changes v1 -> v2 [Matt - Removed comment block and added possibilities of thermocouple type in device tree binding doc. v2 -> v3 - Rebased v3 -> v4 - Removed one-shot property related information. - Used standard name 'temp-sensor' v4 -> v5 [Patrick - Rename thermocouple type to maxim,thermocouple-type for DT entry v5 -> v6 [Patrick - use generic thermocouple-type for DT entry --- .../bindings/iio/temperature/max31856.txt | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt diff --git a/Documentation/devicetree/bindings/iio/temperature/max31856.txt b/Documentation/devicetree/bindings/iio/temperature/max31856.txt new file mode 100644 index 000000000000..06ab43bb4de8 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/temperature/max31856.txt @@ -0,0 +1,24 @@ +Maxim MAX31856 thermocouple support + +https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf + +Optional property: + - thermocouple-type: Type of thermocouple (THERMOCOUPLE_TYPE_K if + omitted). Supported types are B, E, J, K, N, R, S, T. + +Required properties: + - compatible: must be "maxim,max31856" + - reg: SPI chip select number for the device + - spi-max-frequency: As per datasheet max. supported freq is 5000000 + - spi-cpha: must be defined for max31856 to enable SPI mode 1 + + Refer to spi/spi-bus.txt for generic SPI slave bindings. + + Example: + temp-sensor@0 { + compatible = "maxim,max31856"; + reg = <0>; + spi-max-frequency = <5000000>; + spi-cpha; + thermocouple-type = <THERMOCOUPLE_TYPE_K>; + }; -- 2.19.1 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info 2019-03-07 10:34 ` [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info Patrick Havelange @ 2019-03-11 22:28 ` Rob Herring 0 siblings, 0 replies; 8+ messages in thread From: Rob Herring @ 2019-03-11 22:28 UTC (permalink / raw) To: Patrick Havelange Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree, Patrick Havelange On Thu, 7 Mar 2019 11:34:08 +0100, Patrick Havelange wrote: > From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> > > This patch added device tree binding info for MAX31856 driver. > > Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> > Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> > Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> > --- > Changes > v1 -> v2 > [Matt > - Removed comment block and added possibilities of > thermocouple type in device tree binding doc. > > v2 -> v3 > - Rebased > > v3 -> v4 > - Removed one-shot property related information. > - Used standard name 'temp-sensor' > > v4 -> v5 > [Patrick > - Rename thermocouple type to maxim,thermocouple-type for DT entry > > v5 -> v6 > [Patrick > - use generic thermocouple-type for DT entry > --- > .../bindings/iio/temperature/max31856.txt | 24 +++++++++++++++++++ > 1 file changed, 24 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt > Reviewed-by: Rob Herring <robh@kernel.org> ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support 2019-03-07 10:34 [PATCH v6 1/4] dt-bindings: iio/temperature: Add thermocouple types Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info Patrick Havelange @ 2019-03-07 10:34 ` Patrick Havelange 2019-03-10 9:51 ` Jonathan Cameron 2 siblings, 1 reply; 8+ messages in thread From: Patrick Havelange @ 2019-03-07 10:34 UTC (permalink / raw) To: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree Cc: Patrick Havelange From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> 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 <paresh.chaudhary@rockwellcollins.com> Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> --- 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() --- .../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 000000000000..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-iio@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-iio@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 be called tsys02d. +config MAX31856 + tristate "MAX31856 thermocouple sensor" + depends on SPI + help + If you say yes here you get support for MAX31856 + thermocouple sensor chip connected via SPI. + + This driver can also be built as a module. If so, the module + will be called max31856. + endmenu diff --git a/drivers/iio/temperature/Makefile b/drivers/iio/temperature/Makefile index 34a31db0bb63..baca4776ca0d 100644 --- a/drivers/iio/temperature/Makefile +++ b/drivers/iio/temperature/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o +obj-$(CONFIG_MAX31856) += max31856.o obj-$(CONFIG_MLX90614) += mlx90614.o obj-$(CONFIG_MLX90632) += mlx90632.o obj-$(CONFIG_TMP006) += tmp006.o diff --git a/drivers/iio/temperature/max31856.c b/drivers/iio/temperature/max31856.c new file mode 100644 index 000000000000..6b67d6b95cf9 --- /dev/null +++ b/drivers/iio/temperature/max31856.c @@ -0,0 +1,353 @@ +// SPDX-License-Identifier: GPL-2.0 +/* max31856.c + * + * Maxim MAX31856 thermocouple sensor driver + * + * Copyright (C) 2018-2019 Rockwell Collins + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/spi/spi.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <dt-bindings/iio/temperature/thermocouple.h> +/* + * The MSB of the register value determines whether the following byte will + * be written or read. If it is 0, one or more byte reads will follow. + */ +#define MAX31856_RD_WR_BIT BIT(7) + +#define MAX31856_CR0_AUTOCONVERT BIT(7) +#define MAX31856_CR0_1SHOT BIT(6) +#define MAX31856_CR0_OCFAULT BIT(4) +#define MAX31856_CR0_OCFAULT_MASK GENMASK(5, 4) +#define MAX31856_TC_TYPE_MASK GENMASK(3, 0) +#define MAX31856_FAULT_OVUV BIT(1) +#define MAX31856_FAULT_OPEN BIT(0) + +/* The MAX31856 registers */ +#define MAX31856_CR0_REG 0x00 +#define MAX31856_CR1_REG 0x01 +#define MAX31856_MASK_REG 0x02 +#define MAX31856_CJHF_REG 0x03 +#define MAX31856_CJLF_REG 0x04 +#define MAX31856_LTHFTH_REG 0x05 +#define MAX31856_LTHFTL_REG 0x06 +#define MAX31856_LTLFTH_REG 0x07 +#define MAX31856_LTLFTL_REG 0x08 +#define MAX31856_CJTO_REG 0x09 +#define MAX31856_CJTH_REG 0x0A +#define MAX31856_CJTL_REG 0x0B +#define MAX31856_LTCBH_REG 0x0C +#define MAX31856_LTCBM_REG 0x0D +#define MAX31856_LTCBL_REG 0x0E +#define MAX31856_SR_REG 0x0F + +static const struct iio_chan_spec max31856_channels[] = { + { /* Thermocouple Temperature */ + .type = IIO_TEMP, + .info_mask_separate = + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + }, + { /* Cold Junction Temperature */ + .type = IIO_TEMP, + .channel2 = IIO_MOD_TEMP_AMBIENT, + .modified = 1, + .info_mask_separate = + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + }, +}; + +struct max31856_data { + struct spi_device *spi; + u32 thermocouple_type; +}; + +static int max31856_read(struct max31856_data *data, u8 reg, + u8 val[], unsigned int read_size) +{ + return spi_write_then_read(data->spi, ®, 1, val, read_size); +} + +static int max31856_write(struct max31856_data *data, u8 reg, + unsigned int val) +{ + u8 buf[2]; + + buf[0] = reg | (MAX31856_RD_WR_BIT); + buf[1] = val; + + return spi_write(data->spi, buf, 2); +} + +static int max31856_init(struct max31856_data *data) +{ + int ret; + u8 reg_cr0_val, reg_cr1_val; + + /* Start by changing to Off mode before making changes as + * some settings are recommended to be set only when the device + * is off + */ + ret = max31856_read(data, MAX31856_CR0_REG, ®_cr0_val, 1); + if (ret) + return ret; + + reg_cr0_val &= ~MAX31856_CR0_AUTOCONVERT; + ret = max31856_write(data, MAX31856_CR0_REG, reg_cr0_val); + if (ret) + return ret; + + /* Set thermocouple type based on dts property */ + ret = max31856_read(data, MAX31856_CR1_REG, ®_cr1_val, 1); + if (ret) + return ret; + + reg_cr1_val &= ~MAX31856_TC_TYPE_MASK; + reg_cr1_val |= data->thermocouple_type; + ret = max31856_write(data, MAX31856_CR1_REG, reg_cr1_val); + if (ret) + return ret; + + /* + * Enable Open circuit fault detection + * Read datasheet for more information: Table 4. + * Value 01 means : Enabled (Once every 16 conversions) + */ + reg_cr0_val &= ~MAX31856_CR0_OCFAULT_MASK; + reg_cr0_val |= MAX31856_CR0_OCFAULT; + + /* Set Auto Conversion Mode */ + reg_cr0_val &= ~MAX31856_CR0_1SHOT; + reg_cr0_val |= MAX31856_CR0_AUTOCONVERT; + + return max31856_write(data, MAX31856_CR0_REG, reg_cr0_val); +} + +static int max31856_thermocouple_read(struct max31856_data *data, + struct iio_chan_spec const *chan, + int *val) +{ + int ret, offset_cjto; + u8 reg_val[3]; + + switch (chan->channel2) { + case IIO_NO_MOD: + /* + * Multibyte Read + * MAX31856_LTCBH_REG, MAX31856_LTCBM_REG, MAX31856_LTCBL_REG + */ + ret = max31856_read(data, MAX31856_LTCBH_REG, reg_val, 3); + if (ret) + return ret; + /* Skip last 5 dead bits of LTCBL */ + *val = (reg_val[0] << 16 | reg_val[1] << 8 | reg_val[2]) >> 5; + /* Check 7th bit of LTCBH reg. value for sign*/ + if (reg_val[0] & 0x80) + *val -= 0x80000; + break; + + case IIO_MOD_TEMP_AMBIENT: + /* + * Multibyte Read + * MAX31856_CJTO_REG, MAX31856_CJTH_REG, MAX31856_CJTL_REG + */ + ret = max31856_read(data, MAX31856_CJTO_REG, reg_val, 3); + if (ret) + return ret; + /* Get Cold Junction Temp. offset register value */ + offset_cjto = reg_val[0]; + /* Get CJTH and CJTL value and skip last 2 dead bits of CJTL */ + *val = (reg_val[1] << 8 | reg_val[2]) >> 2; + /* As per datasheet add offset into CJTH and CJTL */ + *val += offset_cjto; + /* Check 7th bit of CJTH reg. value for sign */ + if (reg_val[1] & 0x80) + *val -= 0x4000; + break; + + default: + return -EINVAL; + } + + ret = max31856_read(data, MAX31856_SR_REG, reg_val, 1); + if (ret) + return ret; + /* Check for over/under voltage or open circuit fault */ + if (reg_val[0] & (MAX31856_FAULT_OVUV | MAX31856_FAULT_OPEN)) + return -EIO; + + return ret; +} + +static int max31856_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct max31856_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = max31856_thermocouple_read(data, chan, val); + if (ret) + return ret; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + switch (chan->channel2) { + case IIO_MOD_TEMP_AMBIENT: + /* Cold junction Temp. Data resolution is 0.015625 */ + *val = 15; + *val2 = 625000; /* 1000 * 0.015625 */ + ret = IIO_VAL_INT_PLUS_MICRO; + break; + default: + /* Thermocouple Temp. Data resolution is 0.0078125 */ + *val = 7; + *val2 = 812500; /* 1000 * 0.0078125) */ + return IIO_VAL_INT_PLUS_MICRO; + } + break; + } + + return ret; +} + +static ssize_t show_fault(struct device *dev, u8 faultbit, char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct max31856_data *data = iio_priv(indio_dev); + u8 reg_val; + int ret; + bool fault; + + ret = max31856_read(data, MAX31856_SR_REG, ®_val, 1); + if (ret) + return ret; + + fault = reg_val & faultbit; + + return sprintf(buf, "%d\n", fault); +} + +static ssize_t show_fault_ovuv(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return show_fault(dev, MAX31856_FAULT_OVUV, buf); +} + +static ssize_t show_fault_oc(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return show_fault(dev, MAX31856_FAULT_OPEN, buf); +} + +static IIO_DEVICE_ATTR(fault_ovuv, 0444, show_fault_ovuv, NULL, 0); +static IIO_DEVICE_ATTR(fault_oc, 0444, show_fault_oc, NULL, 0); + +static struct attribute *max31856_attributes[] = { + &iio_dev_attr_fault_ovuv.dev_attr.attr, + &iio_dev_attr_fault_oc.dev_attr.attr, + NULL, +}; + +static const struct attribute_group max31856_group = { + .attrs = max31856_attributes, +}; + +static const struct iio_info max31856_info = { + .read_raw = max31856_read_raw, + .attrs = &max31856_group, +}; + +static int max31856_probe(struct spi_device *spi) +{ + const struct spi_device_id *id = spi_get_device_id(spi); + struct iio_dev *indio_dev; + struct max31856_data *data; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + data->spi = spi; + + spi_set_drvdata(spi, indio_dev); + + indio_dev->info = &max31856_info; + indio_dev->name = id->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = max31856_channels; + indio_dev->num_channels = ARRAY_SIZE(max31856_channels); + + ret = of_property_read_u32(spi->dev.of_node, "thermocouple-type", + &data->thermocouple_type); + + if (ret) { + dev_info(&spi->dev, + "Could not read thermocouple type DT property, configuring as a K-Type\n"); + data->thermocouple_type = THERMOCOUPLE_TYPE_K; + } + + /* + * no need to translate values as the supported types + * have the same value as the #defines + */ + switch (data->thermocouple_type) { + case THERMOCOUPLE_TYPE_B: + case THERMOCOUPLE_TYPE_E: + case THERMOCOUPLE_TYPE_J: + case THERMOCOUPLE_TYPE_K: + case THERMOCOUPLE_TYPE_N: + case THERMOCOUPLE_TYPE_R: + case THERMOCOUPLE_TYPE_S: + case THERMOCOUPLE_TYPE_T: + break; + default: + dev_err(&spi->dev, + "error: thermocouple-type %u not supported by max31856\n" + , data->thermocouple_type); + return -EINVAL; + } + + ret = max31856_init(data); + if (ret) { + dev_err(&spi->dev, "error: Failed to configure max31856\n"); + return ret; + } + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct spi_device_id max31856_id[] = { + { "max31856", 0 }, + { } +}; +MODULE_DEVICE_TABLE(spi, max31856_id); + +static const struct of_device_id max31856_of_match[] = { + { .compatible = "maxim,max31856" }, + { } +}; +MODULE_DEVICE_TABLE(of, max31856_of_match); + +static struct spi_driver max31856_driver = { + .driver = { + .name = "max31856", + .of_match_table = max31856_of_match, + }, + .probe = max31856_probe, + .id_table = max31856_id, +}; +module_spi_driver(max31856_driver); + +MODULE_AUTHOR("Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>"); +MODULE_AUTHOR("Patrick Havelange <patrick.havelange@essensium.com>"); +MODULE_DESCRIPTION("Maxim MAX31856 thermocouple sensor driver"); +MODULE_LICENSE("GPL"); -- 2.19.1 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support 2019-03-07 10:34 ` [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support Patrick Havelange @ 2019-03-10 9:51 ` Jonathan Cameron 0 siblings, 0 replies; 8+ messages in thread From: Jonathan Cameron @ 2019-03-10 9:51 UTC (permalink / raw) To: Patrick Havelange Cc: Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler, Rob Herring, Mark Rutland, Matt Weber, Paresh Chaudhary, linux-iio, linux-kernel, devicetree On Thu, 7 Mar 2019 11:34:09 +0100 Patrick Havelange <patrick.havelange@essensium.com> wrote: > From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> > > 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 <paresh.chaudhary@rockwellcollins.com> > Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> > Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> Looks good to me. I'll just wait on the DT parts getting reviewed. 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() > --- > .../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 000000000000..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-iio@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-iio@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 > be called tsys02d. > > +config MAX31856 > + tristate "MAX31856 thermocouple sensor" > + depends on SPI > + help > + If you say yes here you get support for MAX31856 > + thermocouple sensor chip connected via SPI. > + > + This driver can also be built as a module. If so, the module > + will be called max31856. > + > endmenu > diff --git a/drivers/iio/temperature/Makefile b/drivers/iio/temperature/Makefile > index 34a31db0bb63..baca4776ca0d 100644 > --- a/drivers/iio/temperature/Makefile > +++ b/drivers/iio/temperature/Makefile > @@ -5,6 +5,7 @@ > > obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o > obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o > +obj-$(CONFIG_MAX31856) += max31856.o > obj-$(CONFIG_MLX90614) += mlx90614.o > obj-$(CONFIG_MLX90632) += mlx90632.o > obj-$(CONFIG_TMP006) += tmp006.o > diff --git a/drivers/iio/temperature/max31856.c b/drivers/iio/temperature/max31856.c > new file mode 100644 > index 000000000000..6b67d6b95cf9 > --- /dev/null > +++ b/drivers/iio/temperature/max31856.c > @@ -0,0 +1,353 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* max31856.c > + * > + * Maxim MAX31856 thermocouple sensor driver > + * > + * Copyright (C) 2018-2019 Rockwell Collins > + */ > + > +#include <linux/module.h> > +#include <linux/init.h> > +#include <linux/err.h> > +#include <linux/spi/spi.h> > +#include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > +#include <dt-bindings/iio/temperature/thermocouple.h> > +/* > + * The MSB of the register value determines whether the following byte will > + * be written or read. If it is 0, one or more byte reads will follow. > + */ > +#define MAX31856_RD_WR_BIT BIT(7) > + > +#define MAX31856_CR0_AUTOCONVERT BIT(7) > +#define MAX31856_CR0_1SHOT BIT(6) > +#define MAX31856_CR0_OCFAULT BIT(4) > +#define MAX31856_CR0_OCFAULT_MASK GENMASK(5, 4) > +#define MAX31856_TC_TYPE_MASK GENMASK(3, 0) > +#define MAX31856_FAULT_OVUV BIT(1) > +#define MAX31856_FAULT_OPEN BIT(0) > + > +/* The MAX31856 registers */ > +#define MAX31856_CR0_REG 0x00 > +#define MAX31856_CR1_REG 0x01 > +#define MAX31856_MASK_REG 0x02 > +#define MAX31856_CJHF_REG 0x03 > +#define MAX31856_CJLF_REG 0x04 > +#define MAX31856_LTHFTH_REG 0x05 > +#define MAX31856_LTHFTL_REG 0x06 > +#define MAX31856_LTLFTH_REG 0x07 > +#define MAX31856_LTLFTL_REG 0x08 > +#define MAX31856_CJTO_REG 0x09 > +#define MAX31856_CJTH_REG 0x0A > +#define MAX31856_CJTL_REG 0x0B > +#define MAX31856_LTCBH_REG 0x0C > +#define MAX31856_LTCBM_REG 0x0D > +#define MAX31856_LTCBL_REG 0x0E > +#define MAX31856_SR_REG 0x0F > + > +static const struct iio_chan_spec max31856_channels[] = { > + { /* Thermocouple Temperature */ > + .type = IIO_TEMP, > + .info_mask_separate = > + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), > + }, > + { /* Cold Junction Temperature */ > + .type = IIO_TEMP, > + .channel2 = IIO_MOD_TEMP_AMBIENT, > + .modified = 1, > + .info_mask_separate = > + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), > + }, > +}; > + > +struct max31856_data { > + struct spi_device *spi; > + u32 thermocouple_type; > +}; > + > +static int max31856_read(struct max31856_data *data, u8 reg, > + u8 val[], unsigned int read_size) > +{ > + return spi_write_then_read(data->spi, ®, 1, val, read_size); > +} > + > +static int max31856_write(struct max31856_data *data, u8 reg, > + unsigned int val) > +{ > + u8 buf[2]; > + > + buf[0] = reg | (MAX31856_RD_WR_BIT); > + buf[1] = val; > + > + return spi_write(data->spi, buf, 2); > +} > + > +static int max31856_init(struct max31856_data *data) > +{ > + int ret; > + u8 reg_cr0_val, reg_cr1_val; > + > + /* Start by changing to Off mode before making changes as > + * some settings are recommended to be set only when the device > + * is off > + */ > + ret = max31856_read(data, MAX31856_CR0_REG, ®_cr0_val, 1); > + if (ret) > + return ret; > + > + reg_cr0_val &= ~MAX31856_CR0_AUTOCONVERT; > + ret = max31856_write(data, MAX31856_CR0_REG, reg_cr0_val); > + if (ret) > + return ret; > + > + /* Set thermocouple type based on dts property */ > + ret = max31856_read(data, MAX31856_CR1_REG, ®_cr1_val, 1); > + if (ret) > + return ret; > + > + reg_cr1_val &= ~MAX31856_TC_TYPE_MASK; > + reg_cr1_val |= data->thermocouple_type; > + ret = max31856_write(data, MAX31856_CR1_REG, reg_cr1_val); > + if (ret) > + return ret; > + > + /* > + * Enable Open circuit fault detection > + * Read datasheet for more information: Table 4. > + * Value 01 means : Enabled (Once every 16 conversions) > + */ > + reg_cr0_val &= ~MAX31856_CR0_OCFAULT_MASK; > + reg_cr0_val |= MAX31856_CR0_OCFAULT; > + > + /* Set Auto Conversion Mode */ > + reg_cr0_val &= ~MAX31856_CR0_1SHOT; > + reg_cr0_val |= MAX31856_CR0_AUTOCONVERT; > + > + return max31856_write(data, MAX31856_CR0_REG, reg_cr0_val); > +} > + > +static int max31856_thermocouple_read(struct max31856_data *data, > + struct iio_chan_spec const *chan, > + int *val) > +{ > + int ret, offset_cjto; > + u8 reg_val[3]; > + > + switch (chan->channel2) { > + case IIO_NO_MOD: > + /* > + * Multibyte Read > + * MAX31856_LTCBH_REG, MAX31856_LTCBM_REG, MAX31856_LTCBL_REG > + */ > + ret = max31856_read(data, MAX31856_LTCBH_REG, reg_val, 3); > + if (ret) > + return ret; > + /* Skip last 5 dead bits of LTCBL */ > + *val = (reg_val[0] << 16 | reg_val[1] << 8 | reg_val[2]) >> 5; > + /* Check 7th bit of LTCBH reg. value for sign*/ > + if (reg_val[0] & 0x80) > + *val -= 0x80000; > + break; > + > + case IIO_MOD_TEMP_AMBIENT: > + /* > + * Multibyte Read > + * MAX31856_CJTO_REG, MAX31856_CJTH_REG, MAX31856_CJTL_REG > + */ > + ret = max31856_read(data, MAX31856_CJTO_REG, reg_val, 3); > + if (ret) > + return ret; > + /* Get Cold Junction Temp. offset register value */ > + offset_cjto = reg_val[0]; > + /* Get CJTH and CJTL value and skip last 2 dead bits of CJTL */ > + *val = (reg_val[1] << 8 | reg_val[2]) >> 2; > + /* As per datasheet add offset into CJTH and CJTL */ > + *val += offset_cjto; > + /* Check 7th bit of CJTH reg. value for sign */ > + if (reg_val[1] & 0x80) > + *val -= 0x4000; > + break; > + > + default: > + return -EINVAL; > + } > + > + ret = max31856_read(data, MAX31856_SR_REG, reg_val, 1); > + if (ret) > + return ret; > + /* Check for over/under voltage or open circuit fault */ > + if (reg_val[0] & (MAX31856_FAULT_OVUV | MAX31856_FAULT_OPEN)) > + return -EIO; > + > + return ret; > +} > + > +static int max31856_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct max31856_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + ret = max31856_thermocouple_read(data, chan, val); > + if (ret) > + return ret; > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + switch (chan->channel2) { > + case IIO_MOD_TEMP_AMBIENT: > + /* Cold junction Temp. Data resolution is 0.015625 */ > + *val = 15; > + *val2 = 625000; /* 1000 * 0.015625 */ > + ret = IIO_VAL_INT_PLUS_MICRO; > + break; > + default: > + /* Thermocouple Temp. Data resolution is 0.0078125 */ > + *val = 7; > + *val2 = 812500; /* 1000 * 0.0078125) */ > + return IIO_VAL_INT_PLUS_MICRO; > + } > + break; > + } > + > + return ret; > +} > + > +static ssize_t show_fault(struct device *dev, u8 faultbit, char *buf) > +{ > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > + struct max31856_data *data = iio_priv(indio_dev); > + u8 reg_val; > + int ret; > + bool fault; > + > + ret = max31856_read(data, MAX31856_SR_REG, ®_val, 1); > + if (ret) > + return ret; > + > + fault = reg_val & faultbit; > + > + return sprintf(buf, "%d\n", fault); > +} > + > +static ssize_t show_fault_ovuv(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return show_fault(dev, MAX31856_FAULT_OVUV, buf); > +} > + > +static ssize_t show_fault_oc(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return show_fault(dev, MAX31856_FAULT_OPEN, buf); > +} > + > +static IIO_DEVICE_ATTR(fault_ovuv, 0444, show_fault_ovuv, NULL, 0); > +static IIO_DEVICE_ATTR(fault_oc, 0444, show_fault_oc, NULL, 0); > + > +static struct attribute *max31856_attributes[] = { > + &iio_dev_attr_fault_ovuv.dev_attr.attr, > + &iio_dev_attr_fault_oc.dev_attr.attr, > + NULL, > +}; > + > +static const struct attribute_group max31856_group = { > + .attrs = max31856_attributes, > +}; > + > +static const struct iio_info max31856_info = { > + .read_raw = max31856_read_raw, > + .attrs = &max31856_group, > +}; > + > +static int max31856_probe(struct spi_device *spi) > +{ > + const struct spi_device_id *id = spi_get_device_id(spi); > + struct iio_dev *indio_dev; > + struct max31856_data *data; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data)); > + if (!indio_dev) > + return -ENOMEM; > + > + data = iio_priv(indio_dev); > + data->spi = spi; > + > + spi_set_drvdata(spi, indio_dev); > + > + indio_dev->info = &max31856_info; > + indio_dev->name = id->name; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = max31856_channels; > + indio_dev->num_channels = ARRAY_SIZE(max31856_channels); > + > + ret = of_property_read_u32(spi->dev.of_node, "thermocouple-type", > + &data->thermocouple_type); > + > + if (ret) { > + dev_info(&spi->dev, > + "Could not read thermocouple type DT property, configuring as a K-Type\n"); > + data->thermocouple_type = THERMOCOUPLE_TYPE_K; > + } > + > + /* > + * no need to translate values as the supported types > + * have the same value as the #defines > + */ > + switch (data->thermocouple_type) { > + case THERMOCOUPLE_TYPE_B: > + case THERMOCOUPLE_TYPE_E: > + case THERMOCOUPLE_TYPE_J: > + case THERMOCOUPLE_TYPE_K: > + case THERMOCOUPLE_TYPE_N: > + case THERMOCOUPLE_TYPE_R: > + case THERMOCOUPLE_TYPE_S: > + case THERMOCOUPLE_TYPE_T: > + break; > + default: > + dev_err(&spi->dev, > + "error: thermocouple-type %u not supported by max31856\n" > + , data->thermocouple_type); > + return -EINVAL; > + } > + > + ret = max31856_init(data); > + if (ret) { > + dev_err(&spi->dev, "error: Failed to configure max31856\n"); > + return ret; > + } > + > + return devm_iio_device_register(&spi->dev, indio_dev); > +} > + > +static const struct spi_device_id max31856_id[] = { > + { "max31856", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(spi, max31856_id); > + > +static const struct of_device_id max31856_of_match[] = { > + { .compatible = "maxim,max31856" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, max31856_of_match); > + > +static struct spi_driver max31856_driver = { > + .driver = { > + .name = "max31856", > + .of_match_table = max31856_of_match, > + }, > + .probe = max31856_probe, > + .id_table = max31856_id, > +}; > +module_spi_driver(max31856_driver); > + > +MODULE_AUTHOR("Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>"); > +MODULE_AUTHOR("Patrick Havelange <patrick.havelange@essensium.com>"); > +MODULE_DESCRIPTION("Maxim MAX31856 thermocouple sensor driver"); > +MODULE_LICENSE("GPL"); ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2019-03-11 22:28 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-03-07 10:34 [PATCH v6 1/4] dt-bindings: iio/temperature: Add thermocouple types Patrick Havelange 2019-03-07 10:34 ` [PATCH v6 2/4] dt-bindings: iio/temperature: Add doc for thermocouple-type Patrick Havelange 2019-03-10 9:50 ` Jonathan Cameron 2019-03-11 22:26 ` Rob Herring 2019-03-07 10:34 ` [PATCH v6 3/4] iio:temperature:max31856:Add device tree bind info Patrick Havelange 2019-03-11 22:28 ` Rob Herring 2019-03-07 10:34 ` [PATCH v6 4/4] iio:temperature: Add MAX31856 thermocouple support Patrick Havelange 2019-03-10 9:51 ` Jonathan Cameron
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