iio: accel: Add support for ADXL313 accelerometer
Subsystems (4)
Lucas Stankus
maintainerv2 cover iio: accel: Add support for ADXL313 accelerometer
Add driver support and dt-bindings documentation for ADXL313 digital accelerometer.
Changelog v1 -> v2:
- Add vs-supply, vdd-supply and interrupt-names fields in the dt doc
- Add default case for switch statements
- Use function pointer argument in core_probe for interface specific setup
- Check spi->mode & SPI_3WIRE to enable the device's 3wire mode
- Remove unnecessary 0s from id structs and commas after null terminators
Lucas Stankus (2):
dt-bindings: iio: accel: Add binding documentation for ADXL313
iio: accel: Add driver support for ADXL313
.../bindings/iio/accel/adi,adxl313.yaml | 90 +++++ MAINTAINERS | 9 + drivers/iio/accel/Kconfig | 29 ++ drivers/iio/accel/Makefile | 3 + drivers/iio/accel/adxl313.h | 63 ++++ drivers/iio/accel/adxl313_core.c | 321 ++++++++++++++++++ drivers/iio/accel/adxl313_i2c.c | 65 ++++ drivers/iio/accel/adxl313_spi.c | 85 +++++ 8 files changed, 665 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml create mode 100644 drivers/iio/accel/adxl313.h create mode 100644 drivers/iio/accel/adxl313_core.c create mode 100644 drivers/iio/accel/adxl313_i2c.c create mode 100644 drivers/iio/accel/adxl313_spi.c
Signature · 1 line
2.32.0
Lucas Stankus
maintainerPATCH v2 1/2 dt-bindings: iio: accel: Add binding documentation for ADXL313
Add device tree binding documentation for ADXL313 3-axis accelerometer.
Signed-off-by Lucas Stankus <[email protected]>
--- .../bindings/iio/accel/adi,adxl313.yaml | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +90 -0
@@ -0,0 +1,90 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices ADXL313 3-Axis Digital Accelerometer + +maintainers: + - Lucas Stankus <[email protected]> + +description: | + Analog Devices ADXL313 3-Axis Digital Accelerometer that supports + both I2C & SPI interfaces. + https://www.analog.com/en/products/adxl313.html + +properties: + compatible: + enum: + - adi,adxl313 + + reg: + maxItems: 1 + + spi-3wire: true + + spi-cpha: true + + spi-cpol: true + + spi-max-frequency: true + + vs-supply: + description: Regulator that supplies power to the accelerometer + + vdd-supply: + description: Regulator that supplies the digital interface supply voltage + + interrupts: + maxItems: 2 + + interrupt-names: + maxItems: 2 + items: + enum: + - INT1 + - INT2 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + i2c0 { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a I2C device node */ + accelerometer@53 { + compatible = "adi,adxl313"; + reg = <0x53>; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + spi { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a SPI device node */ + accelerometer@0 { + compatible = "adi,adxl313"; + reg = <0>; + spi-max-frequency = <5000000>; + spi-cpol; + spi-cpha; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + };
Signature · 1 line
2.32.0
Rob Herring
maintainerRe: [PATCH v2 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
Quoted 8 lines · Lucas Stankus
Add device tree binding documentation for ADXL313 3-axis accelerometer.
Signed-off-by Lucas Stankus <[email protected]>--- .../bindings/iio/accel/adi,adxl313.yaml | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check' on your patch (DT_CHECKER_FLAGS is new in v5.13):
yamllint warnings/errors:
dtschema/dtc warnings/errors:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml: properties:interrupt-names:items: {'enum': ['INT1', 'INT2']} is not of type 'array'
from schema $id: http://devicetree.org/meta-schemas/string-array.yaml#
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml: ignoring, error in schema: properties: interrupt-names: items
warning: no schema found in file: ./Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml Documentation/devicetree/bindings/iio/accel/adi,adxl313.example.dt.yaml:0:0: /example-0/i2c0/accelerometer@53: failed to match any schema with compatible: ['adi,adxl313'] Documentation/devicetree/bindings/iio/accel/adi,adxl313.example.dt.yaml:0:0: /example-1/spi/accelerometer@0: failed to match any schema with compatible: ['adi,adxl313']
doc reference errors (make refcheckdocs):
See https://patchwork.ozlabs.org/patch/1513753
This check can fail if there are any dependencies. The base for a patch series is generally the most recent rc1.
If you already ran 'make dt_binding_check' and didn't see the above error(s), then make sure 'yamllint' is installed and dt-schema is up to date:
pip3 install dtschema --upgrade
Please check and re-submit.
Rob Herring
maintainerRe: [PATCH v2 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
In reply to Lucas StankusQuoted 33 lines · Lucas Stankus
Add device tree binding documentation for ADXL313 3-axis accelerometer.
Signed-off-by Lucas Stankus <[email protected]>--- .../bindings/iio/accel/adi,adxl313.yaml | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yamlDocumentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +19
-0@@ -0,0 +1,90 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices ADXL313 3-Axis Digital Accelerometer + +maintainers: + - Lucas Stankus <[email protected]> + +description: | + Analog Devices ADXL313 3-Axis Digital Accelerometer that supports + both I2C & SPI interfaces. + https://www.analog.com/en/products/adxl313.html + +properties: + compatible: + enum:
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 29
Quoted 10 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +10
-0+ - adi,adxl313 + + reg: + maxItems: 1 + + spi-3wire: true + + spi-cpha: true + + spi-cpol: true
These 3 generally shouldn't be needed, but can be set from the driver. If they are valid, is any combination of them really valid?
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 40
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +11
-0+ + spi-max-frequency: true + + vs-supply: + description: Regulator that supplies power to the accelerometer + + vdd-supply: + description: Regulator that supplies the digital interface supply voltage + + interrupts: + maxItems: 2
This means there must be 2 entries. If 1 is valid, you need 'minItems'.
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 43
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +3
-0+ + interrupt-names: + maxItems: 2
You need 'minItems' too to fix the error.
Quoted 51 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +47
-0+ items: + enum: + - INT1 + - INT2 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + i2c0 { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a I2C device node */ + accelerometer@53 { + compatible = "adi,adxl313"; + reg = <0x53>; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + spi { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a SPI device node */ + accelerometer@0 { + compatible = "adi,adxl313"; + reg = <0>; + spi-max-frequency = <5000000>; + spi-cpol; + spi-cpha; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + };Signature · 1 line
2.32.0
Lucas Stankus
maintainerRe: [PATCH v2 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
Quoted 40 lines · Rob Herring
Quoted 38 lines · Lucas Stankus
Add device tree binding documentation for ADXL313 3-axis accelerometer.
Signed-off-by Lucas Stankus <[email protected]>--- .../bindings/iio/accel/adi,adxl313.yaml | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yamlDocumentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +24
-0@@ -0,0 +1,90 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices ADXL313 3-Axis Digital Accelerometer + +maintainers: + - Lucas Stankus <[email protected]> + +description: | + Analog Devices ADXL313 3-Axis Digital Accelerometer that supports + both I2C & SPI interfaces. + https://www.analog.com/en/products/adxl313.html + +properties: + compatible: + enum: + - adi,adxl313 + + reg: + maxItems: 1 +
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 29
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +5
-0+ spi-3wire: true + + spi-cpha: true + + spi-cpol: trueThese 3 generally shouldn't be needed, but can be set from the driver. If they are valid, is any combination of them really valid?
Only the 3wire is optional, both cpha and cpol are required for proper spi connection.
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +5
-0+ + spi-max-frequency: true + + vs-supply: + description: Regulator that supplies power to the accelerometer
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 40
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +6
-0+ + vdd-supply: + description: Regulator that supplies the digital interface supply voltage + + interrupts: + maxItems: 2This means there must be 2 entries. If 1 is valid, you need 'minItems'.
I'll add 'minItems' for the v3 then, thanks!
Quoted 6 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 43
Quoted 3 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +3
-0+ + interrupt-names: + maxItems: 2You need 'minItems' too to fix the error.
Thank you again and sorry for not catching that error before submitting.
Quoted 51 lines
Quoted 51 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +47
-1+ items: + enum: + - INT1 + - INT2 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + i2c0 { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a I2C device node */ + accelerometer@53 { + compatible = "adi,adxl313"; + reg = <0x53>; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + spi { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a SPI device node */ + accelerometer@0 { + compatible = "adi,adxl313"; + reg = <0>; + spi-max-frequency = <5000000>; + spi-cpol; + spi-cpha; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; --2.32.0
Jonathan Cameron
maintainerRe: [PATCH v2 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
Quoted 51 lines · On Fri, 6 Aug 2021 21:33:44 -0300 Lucas Stankus <[email protected]>…
Quoted 40 lines · Rob Herring
Quoted 38 lines · Lucas Stankus
Add device tree binding documentation for ADXL313 3-axis accelerometer.
Signed-off-by Lucas Stankus <[email protected]>--- .../bindings/iio/accel/adi,adxl313.yaml | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yamlDocumentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +24
-0@@ -0,0 +1,90 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices ADXL313 3-Axis Digital Accelerometer + +maintainers: + - Lucas Stankus <[email protected]> + +description: | + Analog Devices ADXL313 3-Axis Digital Accelerometer that supports + both I2C & SPI interfaces. + https://www.analog.com/en/products/adxl313.html + +properties: + compatible: + enum: + - adi,adxl313 + + reg: + maxItems: 1 +Quoted 9 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 29
Quoted 5 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +5
-0+ spi-3wire: true + + spi-cpha: true + + spi-cpol: trueThese 3 generally shouldn't be needed, but can be set from the driver. If they are valid, is any combination of them really valid?
Quoted 2 lines
Only the 3wire is optional, both cpha and cpol are required for proper spi connection.
We've been round this one a few time, and last time we discussed the cases where you'd need these in DT (because of inverters on the bus)
https://lore.kernel.org/linux-iio/[email protected]/
conclusion was, that we don't want to put the burden on the dt files for those odd cases. The equivalent for interrupt lines is interestingly different because in those cases the two-cell version includes the type of interrupt, so it makes little sense to push that down into the drivers as well.
Mind you I'm not 100% sure how we would retrofit a binding if necessary for the inverted cases. Hope we don't hit one here :)
As you note, 3wire is needed in the binding because it's optional.
Jonathan
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Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 40
Quoted 12 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +11
-0+ + spi-max-frequency: true + + vs-supply: + description: Regulator that supplies power to the accelerometer + + vdd-supply: + description: Regulator that supplies the digital interface supply voltage + + interrupts: + maxItems: 2This means there must be 2 entries. If 1 is valid, you need 'minItems'.
I'll add 'minItems' for the v3 then, thanks!
Quoted 6 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml line 43
Quoted 3 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +3
-0+ + interrupt-names: + maxItems: 2You need 'minItems' too to fix the error.
Thank you again and sorry for not catching that error before submitting.
Quoted 51 lines
Quoted 51 lines
Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml new file +47
-1+ items: + enum: + - INT1 + - INT2 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + i2c0 { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a I2C device node */ + accelerometer@53 { + compatible = "adi,adxl313"; + reg = <0x53>; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/irq.h> + spi { + #address-cells = <1>; + #size-cells = <0>; + + /* Example for a SPI device node */ + accelerometer@0 { + compatible = "adi,adxl313"; + reg = <0>; + spi-max-frequency = <5000000>; + spi-cpol; + spi-cpha; + interrupt-parent = <&gpio0>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "INT1"; + }; + }; --2.32.0
Lucas Stankus
maintainerPATCH v2 2/2 iio: accel: Add driver support for ADXL313
In reply to Lucas StankusADXL313 is a small, thin, low power, 3-axis accelerometer with high resolution measurement up to +/-4g. It includes an integrated 32-level FIFO and has activity and inactivity sensing capabilities.
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
Signed-off-by Lucas Stankus <[email protected]>
--- MAINTAINERS | 9 + drivers/iio/accel/Kconfig | 29 +++ drivers/iio/accel/Makefile | 3 + drivers/iio/accel/adxl313.h | 63 ++++++ drivers/iio/accel/adxl313_core.c | 321 +++++++++++++++++++++++++++++++ drivers/iio/accel/adxl313_i2c.c | 65 +++++++ drivers/iio/accel/adxl313_spi.c | 85 ++++++++ 7 files changed, 575 insertions(+) create mode 100644 drivers/iio/accel/adxl313.h create mode 100644 drivers/iio/accel/adxl313_core.c create mode 100644 drivers/iio/accel/adxl313_i2c.c create mode 100644 drivers/iio/accel/adxl313_spi.c
MAINTAINERS +9 -0
@@ -585,6 +585,15 @@ L: [email protected] S: Maintained F: drivers/platform/x86/adv_swbutton.c +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER +M: Lucas Stankus <[email protected]> +S: Supported +F: Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml +F: drivers/iio/accel/adxl313.h +F: drivers/iio/accel/adxl313_core.c +F: drivers/iio/accel/adxl313_i2c.c +F: drivers/iio/accel/adxl313_spi.c + ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346) M: Michael Hennerich <[email protected]> S: Supported
drivers/iio/accel/Kconfig +29 -0
@@ -30,6 +30,35 @@ config ADIS16209 To compile this driver as a module, say M here: the module will be called adis16209. +config ADXL313 + tristate + +config ADXL313_I2C + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver" + depends on I2C + select ADXL313 + select REGMAP_I2C + help + Say Y here if you want to build i2c support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_i2c and you will also get adxl313_core + for the core module. + +config ADXL313_SPI + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver" + depends on SPI + select ADXL313 + select REGMAP_SPI + help + Say Y here if you want to build spi support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_spi and you will also get adxl313_core + for the core module. + config ADXL345 tristate
drivers/iio/accel/Makefile +3 -0
@@ -6,6 +6,9 @@ # When adding new entries keep the list in alphabetical order obj-$(CONFIG_ADIS16201) += adis16201.o obj-$(CONFIG_ADIS16209) += adis16209.o +obj-$(CONFIG_ADXL313) += adxl313_core.o +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o obj-$(CONFIG_ADXL345) += adxl345_core.o obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
drivers/iio/accel/adxl313.h new file +63 -0
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drivers/iio/accel/adxl313_core.c new file +321 -0
321 lines not on this page · raw message
drivers/iio/accel/adxl313_i2c.c new file +65 -0
65 lines not on this page · raw message
drivers/iio/accel/adxl313_spi.c new file +85 -0
85 lines not on this page · raw message
Signature · 1 line
2.32.0
Re: [PATCH v2 2/2] iio: accel: Add driver support for ADXL313
Quoted 5 lines · Lucas Stankus
ADXL313 is a small, thin, low power, 3-axis accelerometer with high resolution measurement up to +/-4g. It includes an integrated 32-level FIFO and has activity and inactivity sensing capabilities.
Reviewed-by Alexandru Ardelean <[email protected]>
Quoted 651 lines
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
Signed-off-by Lucas Stankus <[email protected]>--- MAINTAINERS | 9 + drivers/iio/accel/Kconfig | 29 +++ drivers/iio/accel/Makefile | 3 + drivers/iio/accel/adxl313.h | 63 ++++++ drivers/iio/accel/adxl313_core.c | 321 +++++++++++++++++++++++++++++++ drivers/iio/accel/adxl313_i2c.c | 65 +++++++ drivers/iio/accel/adxl313_spi.c | 85 ++++++++ 7 files changed, 575 insertions(+) create mode 100644 drivers/iio/accel/adxl313.h create mode 100644 drivers/iio/accel/adxl313_core.c create mode 100644 drivers/iio/accel/adxl313_i2c.c create mode 100644 drivers/iio/accel/adxl313_spi.cMAINTAINERS +9
-0@@ -585,6 +585,15 @@ L: [email protected] S: Maintained F: drivers/platform/x86/adv_swbutton.c +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER +M: Lucas Stankus <[email protected]> +S: Supported +F: Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml +F: drivers/iio/accel/adxl313.h +F: drivers/iio/accel/adxl313_core.c +F: drivers/iio/accel/adxl313_i2c.c +F: drivers/iio/accel/adxl313_spi.c + ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346) M: Michael Hennerich <[email protected]> S: Supporteddrivers/iio/accel/Kconfig +29
-0@@ -30,6 +30,35 @@ config ADIS16209 To compile this driver as a module, say M here: the module will be called adis16209. +config ADXL313 + tristate + +config ADXL313_I2C + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver" + depends on I2C + select ADXL313 + select REGMAP_I2C + help + Say Y here if you want to build i2c support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_i2c and you will also get adxl313_core + for the core module. + +config ADXL313_SPI + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver" + depends on SPI + select ADXL313 + select REGMAP_SPI + help + Say Y here if you want to build spi support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_spi and you will also get adxl313_core + for the core module. + config ADXL345 tristatedrivers/iio/accel/Makefile +3
-0@@ -6,6 +6,9 @@ # When adding new entries keep the list in alphabetical order obj-$(CONFIG_ADIS16201) += adis16201.o obj-$(CONFIG_ADIS16209) += adis16209.o +obj-$(CONFIG_ADXL313) += adxl313_core.o +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o obj-$(CONFIG_ADXL345) += adxl345_core.o obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.odrivers/iio/accel/adxl313.h new file +63
-0@@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +*/ + +#ifndef _ADXL313_H_ +#define _ADXL313_H_ + +/* ADXL313 register definitions */ +#define ADXL313_REG_DEVID0 0x00 +#define ADXL313_REG_DEVID1 0x01 +#define ADXL313_REG_PARTID 0x02 +#define ADXL313_REG_XID 0x04 +#define ADXL313_REG_SOFT_RESET 0x18 +#define ADXL313_REG_OFS_AXIS (index) (0x1E + (index)) +#define ADXL313_REG_THRESH_ACT 0x24 +#define ADXL313_REG_ACT_INACT_CTL 0x27 +#define ADXL313_REG_BW_RATE 0x2C +#define ADXL313_REG_POWER_CTL 0x2D +#define ADXL313_REG_INT_MAP 0x2F +#define ADXL313_REG_DATA_FORMAT 0x31 +#define ADXL313_REG_DATAX 0x32 +#define ADXL313_REG_DATAY 0x34 +#define ADXL313_REG_DATAZ 0x36 +#define ADXL313_REG_FIFO_CTL 0x38 +#define ADXL313_REG_FIFO_STATUS 0x39 + +#define ADXL313_DEVID0 0xAD +#define ADXL313_DEVID1 0x1D +#define ADXL313_PARTID 0xCB +#define ADXL313_SOFT_RESET 0x52 + +#define ADXL313_RATE_MSK GENMASK(3, 0) +#define ADXL313_RATE_BASE 6 + +#define ADXL313_POWER_CTL_MSK GENMASK(3, 2) +#define ADXL313_MEASUREMENT_MODE BIT(3) + +#define ADXL313_RANGE_MSK GENMASK(1, 0) +#define ADXL313_RANGE_4G 3 + +#define ADXL313_FULL_RES BIT(3) +#define ADXL313_SPI_3WIRE BIT(6) +#define ADXL313_I2C_DISABLE BIT(6) + +/* +* Scale for any g range is given in datasheet as +* 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2 +*/ +#define ADXL313_NSCALE 9576806 + +extern const struct regmap_access_table adxl313_readable_regs_table; + +extern const struct regmap_access_table adxl313_writable_regs_table; + +int adxl313_core_probe (struct device *dev, +struct regmap *regmap, +const char *name, +int (*interface_specific_setup)(struct device *, +struct regmap *)); +#endif /* _ADXL313_H_ */ drivers/iio/accel/adxl313_core.c new file +321
-0@@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/bitfield.h> +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "adxl313.h" + +const struct regmap_range adxl313_readable_reg_range[] = { +regmap_reg_range (ADXL313_REG_DEVID0 ,ADXL313_REG_XID ), +regmap_reg_range (ADXL313_REG_SOFT_RESET ,ADXL313_REG_SOFT_RESET ), +regmap_reg_range (ADXL313_REG_OFS_AXIS (0 ),ADXL313_REG_OFS_AXIS (2 )), +regmap_reg_range (ADXL313_REG_THRESH_ACT ,ADXL313_REG_ACT_INACT_CTL ), +regmap_reg_range (ADXL313_REG_BW_RATE ,ADXL313_REG_FIFO_STATUS ) +}; + +const struct regmap_access_table adxl313_readable_regs_table = { + .yes_ranges = adxl313_readable_reg_range, + .n_yes_ranges =ARRAY_SIZE (adxl313_readable_reg_range) +}; +EXPORT_SYMBOL_GPL (adxl313_readable_regs_table); + +const struct regmap_range adxl313_writable_reg_range[] = { +regmap_reg_range (ADXL313_REG_SOFT_RESET ,ADXL313_REG_SOFT_RESET ), +regmap_reg_range (ADXL313_REG_OFS_AXIS (0 ),ADXL313_REG_OFS_AXIS (2 )), +regmap_reg_range (ADXL313_REG_THRESH_ACT ,ADXL313_REG_ACT_INACT_CTL ), +regmap_reg_range (ADXL313_REG_BW_RATE ,ADXL313_REG_INT_MAP ), +regmap_reg_range (ADXL313_REG_DATA_FORMAT ,ADXL313_REG_DATA_FORMAT ), +regmap_reg_range (ADXL313_REG_FIFO_CTL ,ADXL313_REG_FIFO_CTL ) +}; + +const struct regmap_access_table adxl313_writable_regs_table = { + .yes_ranges = adxl313_writable_reg_range, + .n_yes_ranges =ARRAY_SIZE (adxl313_writable_reg_range) +}; +EXPORT_SYMBOL_GPL (adxl313_writable_regs_table); + +struct adxl313_data { +struct regmap *regmap; +struct mutex lock;/* lock to protect transf_buf */ +__le16 transf_buf____cacheline_aligned ; +}; + +static const int adxl313_odr_freqs[][2 ] = { + [0 ] = {6 ,250000 }, + [1 ] = {12 ,500000 }, + [2 ] = {25 ,0 }, + [3 ] = {50 ,0 }, + [4 ] = {100 ,0 }, + [5 ] = {200 ,0 }, + [6 ] = {400 ,0 }, + [7 ] = {800 ,0 }, + [8 ] = {1600 ,0 }, + [9 ] = {3200 ,0 }, +}; + +#define ADXL313_ACCEL_CHANNEL (index, addr, axis) { \ + .type = IIO_ACCEL, \ + .address = addr, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_CALIBBIAS), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .info_mask_shared_by_type_available = \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 13, \ + .storagebits = 16, \ + .endianness = IIO_LE, \ + }, \ +} + +static const struct iio_chan_spec adxl313_channels[] = { +ADXL313_ACCEL_CHANNEL (0 ,ADXL313_REG_DATAX ,X ), +ADXL313_ACCEL_CHANNEL (1 ,ADXL313_REG_DATAY ,Y ), +ADXL313_ACCEL_CHANNEL (2 ,ADXL313_REG_DATAZ ,Z ), +}; + +static int adxl313_set_odr (struct adxl313_data *data, +unsigned int freq1,unsigned int freq2) +{ +unsigned int i; + +for (i =0 ; i <ARRAY_SIZE (adxl313_odr_freqs); i++) { +if (adxl313_odr_freqs[i][0 ] == freq1 && + adxl313_odr_freqs[i][1 ] == freq2) +break ; + } + +if (i ==ARRAY_SIZE (adxl313_odr_freqs)) +return -EINVAL ; + +return regmap_update_bits (data->regmap,ADXL313_REG_BW_RATE , +ADXL313_RATE_MSK , +FIELD_PREP (ADXL313_RATE_MSK , +ADXL313_RATE_BASE + i)); +} + +static int adxl313_read_axis (struct adxl313_data *data, +struct iio_chan_spec const *chan) +{ +int ret; + +mutex_lock (&data->lock); + + ret =regmap_bulk_read (data->regmap, + chan->address, + &data->transf_buf,2 ); +if (ret) + goto unlock_ret; + + ret =le16_to_cpu (data->transf_buf); + +unlock_ret: +mutex_unlock (&data->lock); +return ret; +} + +static int adxl313_read_freq_avail (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +const int **vals,int *type,int *length, +long mask) +{ +switch (mask) { +case IIO_CHAN_INFO_SAMP_FREQ : + *vals = (const int *)adxl313_odr_freqs; + *length =ARRAY_SIZE (adxl313_odr_freqs) *2 ; + *type =IIO_VAL_INT_PLUS_MICRO ; +return IIO_AVAIL_LIST ; +default : +return -EINVAL ; + } +} + +static int adxl313_read_raw (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +int *val,int *val2,long mask) +{ +struct adxl313_data *data =iio_priv (indio_dev); +unsigned int regval; +int ret; + +switch (mask) { +case IIO_CHAN_INFO_RAW : + ret =adxl313_read_axis (data, chan); +if (ret <0 ) +return ret; + + *val =sign_extend32 (ret, chan->scan_type.realbits -1 ); +return IIO_VAL_INT ; +case IIO_CHAN_INFO_SCALE : + *val =0 ; + *val2 =ADXL313_NSCALE ; +return IIO_VAL_INT_PLUS_NANO ; +case IIO_CHAN_INFO_CALIBBIAS : + ret =regmap_read (data->regmap, +ADXL313_REG_OFS_AXIS (chan->scan_index), + ®val); +if (ret) +return ret; + +/* +* 8-bit resolution at +/- 0.5g, that is 4x accel data scale +* factor at full resolution +*/ + *val =sign_extend32 (regval,7 ) *4 ; +return IIO_VAL_INT ; +case IIO_CHAN_INFO_SAMP_FREQ : + ret =regmap_read (data->regmap,ADXL313_REG_BW_RATE , ®val); +if (ret) +return ret; + + ret =FIELD_GET (ADXL313_RATE_MSK , regval) -ADXL313_RATE_BASE ; + *val = adxl313_odr_freqs[ret][0 ]; + *val2 = adxl313_odr_freqs[ret][1 ]; +return IIO_VAL_INT_PLUS_MICRO ; +default : +return -EINVAL ; + } +} + +static int adxl313_write_raw (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +int val,int val2,long mask) +{ +struct adxl313_data *data =iio_priv (indio_dev); + +switch (mask) { +case IIO_CHAN_INFO_CALIBBIAS : +/* +* 8-bit resolution at +/- 0.5g, that is 4x accel data scale +* factor at full resolution +*/ +if (val >127 *4 || val <-128 *4 ) +return -EINVAL ; + +return regmap_write (data->regmap, +ADXL313_REG_OFS_AXIS (chan->scan_index), + val /4 ); +case IIO_CHAN_INFO_SAMP_FREQ : +return adxl313_set_odr (data, val, val2); +default : +return -EINVAL ; + } +} + +static const struct iio_info adxl313_info = { + .read_raw = adxl313_read_raw, + .write_raw = adxl313_write_raw, + .read_avail = adxl313_read_freq_avail +}; + +static int adxl313_setup (struct device *dev,struct adxl313_data *data, +int (*interface_specific_setup)(struct device *, +struct regmap *)) +{ +unsigned int regval; +int ret; + + ret =regmap_read (data->regmap,ADXL313_REG_DEVID0 , ®val); +if (ret) +return ret; + +if (interface_specific_setup) { + ret =interface_specific_setup (dev, data->regmap); +if (ret) +return ret; + } + +if (regval !=ADXL313_DEVID0 ) { +dev_err (dev,"Invalid manufacturer ID: 0x%02x\n" , regval); +return -ENODEV ; + } + + ret =regmap_read (data->regmap,ADXL313_REG_DEVID1 , ®val); +if (ret) +return ret; + +if (regval !=ADXL313_DEVID1 ) { +dev_err (dev,"Invalid mems ID: 0x%02x\n" , regval); +return -ENODEV ; + } + + ret =regmap_read (data->regmap,ADXL313_REG_PARTID , ®val); +if (ret) +return ret; + +if (regval !=ADXL313_PARTID ) { +dev_err (dev,"Invalid device ID: 0x%02x\n" , regval); +return -ENODEV ; + } + +/* Sets the range to +/- 4g */ + ret =regmap_update_bits (data->regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_RANGE_MSK , +FIELD_PREP (ADXL313_RANGE_MSK , +ADXL313_RANGE_4G )); +if (ret) +return ret; + +/* Enables full resolution */ + ret =regmap_update_bits (data->regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_FULL_RES ,ADXL313_FULL_RES ); +if (ret) +return ret; + +/* Enables measurement mode */ +return regmap_update_bits (data->regmap,ADXL313_REG_POWER_CTL , +ADXL313_POWER_CTL_MSK , +ADXL313_MEASUREMENT_MODE ); +} + +int adxl313_core_probe (struct device *dev, +struct regmap *regmap, +const char *name, +int (*interface_specific_setup)(struct device *, +struct regmap *)) +{ +struct adxl313_data *data; +struct iio_dev *indio_dev; +int ret; + + indio_dev =devm_iio_device_alloc (dev,sizeof (*data)); +if (!indio_dev) +return -ENOMEM ; + + data =iio_priv (indio_dev); + data->regmap = regmap; +mutex_init (&data->lock); + + indio_dev->name = name; + indio_dev->info = &adxl313_info; + indio_dev->modes =INDIO_DIRECT_MODE ; + indio_dev->channels = adxl313_channels; + indio_dev->num_channels =ARRAY_SIZE (adxl313_channels); + + ret =adxl313_setup (dev, data, interface_specific_setup); +if (ret) { +dev_err (dev,"ADXL313 setup failed\n" ); +return ret; + } + +return devm_iio_device_register (dev, indio_dev); +} +EXPORT_SYMBOL_GPL (adxl313_core_probe); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer core driver" ); +MODULE_LICENSE ("GPL v2" );drivers/iio/accel/adxl313_i2c.c new file +65
-0@@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "adxl313.h" + +static const struct regmap_config adxl313_i2c_regmap_config = { + .reg_bits =8 , + .val_bits =8 , + .rd_table = &adxl313_readable_regs_table, + .wr_table = &adxl313_writable_regs_table, + .max_register =0x39 +}; + +static int adxl313_i2c_probe (struct i2c_client *client) +{ +struct regmap *regmap; + + regmap =devm_regmap_init_i2c (client, &adxl313_i2c_regmap_config); +if (IS_ERR (regmap)) { +dev_err (&client->dev,"Error initializing i2c regmap: %ld\n" , +PTR_ERR (regmap)); +return PTR_ERR (regmap); + } + +return adxl313_core_probe (&client->dev, regmap, client->name,NULL ); +} + +static const struct i2c_device_id adxl313_i2c_id[] = { + {"adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (i2c, adxl313_i2c_id); + +static const struct of_device_id adxl313_of_match[] = { + { .compatible ="adi,adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (of, adxl313_of_match); + +static struct i2c_driver adxl313_i2c_driver = { + .driver = { + .name ="adxl313_i2c" , + .of_match_table = adxl313_of_match, + }, + .probe_new = adxl313_i2c_probe, + .id_table = adxl313_i2c_id +}; + +module_i2c_driver (adxl313_i2c_driver); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer I2C driver" ); +MODULE_LICENSE ("GPL v2" );drivers/iio/accel/adxl313_spi.c new file +85
-1@@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#include "adxl313.h" + +static const struct regmap_config adxl313_spi_regmap_config = { + .reg_bits =8 , + .val_bits =8 , + .rd_table = &adxl313_readable_regs_table, + .wr_table = &adxl313_writable_regs_table, + .max_register =0x39 , +/* Setting bits 7 and 6 enables multiple-byte read */ + .read_flag_mask =BIT (7 ) |BIT (6 ) +}; + +static int adxl313_spi_setup (struct device *dev,struct regmap *regmap) +{ + struct spi_device *spi = container_of(dev, struct spi_device, dev); +int ret; + +if (spi->mode &SPI_3WIRE ) { + ret =regmap_write (regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_SPI_3WIRE ); +if (ret) +return ret; + } + +return regmap_update_bits (regmap,ADXL313_REG_POWER_CTL , +ADXL313_I2C_DISABLE ,ADXL313_I2C_DISABLE ); +} + +static int adxl313_spi_probe (struct spi_device *spi) +{ +const struct spi_device_id *id =spi_get_device_id (spi); +struct regmap *regmap; + + regmap =devm_regmap_init_spi (spi, &adxl313_spi_regmap_config); +if (IS_ERR (regmap)) { +dev_err (&spi->dev,"Error initializing spi regmap: %ld\n" , +PTR_ERR (regmap)); +return PTR_ERR (regmap); + } + +return adxl313_core_probe (&spi->dev, regmap, id->name, + &adxl313_spi_setup); +} + +static const struct spi_device_id adxl313_spi_id[] = { + {"adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (spi, adxl313_spi_id); + +static const struct of_device_id adxl313_of_match[] = { + { .compatible ="adi,adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (of, adxl313_of_match); + +static struct spi_driver adxl313_spi_driver = { + .driver = { + .name ="adxl313_spi" , + .of_match_table = adxl313_of_match, + }, + .probe = adxl313_spi_probe, + .id_table = adxl313_spi_id +}; + +module_spi_driver (adxl313_spi_driver); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer SPI driver" ); +MODULE_LICENSE ("GPL v2" ); --2.32.0
A message that is not in the archive (sent off-list or not yet received): CAHp75Ve7avWpdnCioW6qdT21NqjK1TTW-nwFsz6x+0JLXsQH3Q@mail.gmail.com
Lucas Stankus
maintainerRe: [PATCH v2 2/2] iio: accel: Add driver support for ADXL313
Quoted 33 lines · Andy Shevchenko
Quoted 29 lines · Lucas Stankus
ADXL313 is a small, thin, low power, 3-axis accelerometer with high resolution measurement up to +/-4g. It includes an integrated 32-level FIFO and has activity and inactivity sensing capabilities.
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
Signed-off-by Lucas Stankus <[email protected]>--- MAINTAINERS | 9 + drivers/iio/accel/Kconfig | 29 +++ drivers/iio/accel/Makefile | 3 + drivers/iio/accel/adxl313.h | 63 ++++++ drivers/iio/accel/adxl313_core.c | 321 +++++++++++++++++++++++++++++++ drivers/iio/accel/adxl313_i2c.c | 65 +++++++ drivers/iio/accel/adxl313_spi.c | 85 ++++++++ 7 files changed, 575 insertions(+) create mode 100644 drivers/iio/accel/adxl313.h create mode 100644 drivers/iio/accel/adxl313_core.c create mode 100644 drivers/iio/accel/adxl313_i2c.c create mode 100644 drivers/iio/accel/adxl313_spi.cMAINTAINERS +0
-0@@ -585,6 +585,15 @@ L: [email protected] S: Maintained F: drivers/platform/x86/adv_swbutton.c
Quoted 13 lines
MAINTAINERS L: [email protected] · line 595
Quoted 8 lines
MAINTAINERS +8
-0+ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER +M: Lucas Stankus <[email protected]> +S: Supported +F: Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml +F: drivers/iio/accel/adxl313.h +F: drivers/iio/accel/adxl313_core.c +F: drivers/iio/accel/adxl313_i2c.c +F: drivers/iio/accel/adxl313_spi.cadxl313*?
Didn't know this would work, but I think I prefer the way it is now. Are you proposing this as a suggestion or more of a change request?
Quoted 113 lines
Quoted 113 lines
MAINTAINERS +1
-0+ ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346) M: Michael Hennerich <[email protected]> S: Supporteddrivers/iio/accel/Kconfig +29
-0@@ -30,6 +30,35 @@ config ADIS16209 To compile this driver as a module, say M here: the module will be called adis16209. +config ADXL313 + tristate + +config ADXL313_I2C + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver" + depends on I2C + select ADXL313 + select REGMAP_I2C + help + Say Y here if you want to build i2c support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_i2c and you will also get adxl313_core + for the core module. + +config ADXL313_SPI + tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver" + depends on SPI + select ADXL313 + select REGMAP_SPI + help + Say Y here if you want to build spi support for the Analog Devices + ADXL313 3-axis digital accelerometer. + + To compile this driver as a module, choose M here: the module + will be called adxl313_spi and you will also get adxl313_core + for the core module. + config ADXL345 tristatedrivers/iio/accel/Makefile +3
-0@@ -6,6 +6,9 @@ # When adding new entries keep the list in alphabetical order obj-$(CONFIG_ADIS16201) += adis16201.o obj-$(CONFIG_ADIS16209) += adis16209.o +obj-$(CONFIG_ADXL313) += adxl313_core.o +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o obj-$(CONFIG_ADXL345) += adxl345_core.o obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.odrivers/iio/accel/adxl313.h new file +48
-0@@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +*/ + +#ifndef _ADXL313_H_ +#define _ADXL313_H_ + +/* ADXL313 register definitions */ +#define ADXL313_REG_DEVID0 0x00 +#define ADXL313_REG_DEVID1 0x01 +#define ADXL313_REG_PARTID 0x02 +#define ADXL313_REG_XID 0x04 +#define ADXL313_REG_SOFT_RESET 0x18 +#define ADXL313_REG_OFS_AXIS (index) (0x1E + (index)) +#define ADXL313_REG_THRESH_ACT 0x24 +#define ADXL313_REG_ACT_INACT_CTL 0x27 +#define ADXL313_REG_BW_RATE 0x2C +#define ADXL313_REG_POWER_CTL 0x2D +#define ADXL313_REG_INT_MAP 0x2F +#define ADXL313_REG_DATA_FORMAT 0x31 +#define ADXL313_REG_DATAX 0x32 +#define ADXL313_REG_DATAY 0x34 +#define ADXL313_REG_DATAZ 0x36 +#define ADXL313_REG_FIFO_CTL 0x38 +#define ADXL313_REG_FIFO_STATUS 0x39 + +#define ADXL313_DEVID0 0xAD +#define ADXL313_DEVID1 0x1D +#define ADXL313_PARTID 0xCB +#define ADXL313_SOFT_RESET 0x52 + +#define ADXL313_RATE_MSK GENMASK(3, 0) +#define ADXL313_RATE_BASE 6 + +#define ADXL313_POWER_CTL_MSK GENMASK(3, 2) +#define ADXL313_MEASUREMENT_MODE BIT(3) + +#define ADXL313_RANGE_MSK GENMASK(1, 0) +#define ADXL313_RANGE_4G 3 + +#define ADXL313_FULL_RES BIT(3) +#define ADXL313_SPI_3WIRE BIT(6) +#define ADXL313_I2C_DISABLE BIT(6) + +/*
Quoted 9 lines
drivers/iio/accel/adxl313.h line 52
Quoted 4 lines
drivers/iio/accel/adxl313.h new file +4
-0+* Scale for any g range is given in datasheet as +* 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2 +*/ +#define ADXL313_NSCALE 9576806Is it in nanonewtons? Perhaps add a suffix
_nN?
It's actually in meters per second squared, so I couldn't come up with a good suffix. Do you have any suggestions?
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Quoted 214 lines
drivers/iio/accel/adxl313.h new file +11
-0+ +extern const struct regmap_access_table adxl313_readable_regs_table; + +extern const struct regmap_access_table adxl313_writable_regs_table; + +int adxl313_core_probe (struct device *dev, +struct regmap *regmap, +const char *name, +int (*interface_specific_setup)(struct device *, +struct regmap *)); +#endif /* _ADXL313_H_ */ drivers/iio/accel/adxl313_core.c new file +196
-0@@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/bitfield.h> +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "adxl313.h" + +const struct regmap_range adxl313_readable_reg_range[] = { +regmap_reg_range (ADXL313_REG_DEVID0 ,ADXL313_REG_XID ), +regmap_reg_range (ADXL313_REG_SOFT_RESET ,ADXL313_REG_SOFT_RESET ), +regmap_reg_range (ADXL313_REG_OFS_AXIS (0 ),ADXL313_REG_OFS_AXIS (2 )), +regmap_reg_range (ADXL313_REG_THRESH_ACT ,ADXL313_REG_ACT_INACT_CTL ), +regmap_reg_range (ADXL313_REG_BW_RATE ,ADXL313_REG_FIFO_STATUS ) +}; + +const struct regmap_access_table adxl313_readable_regs_table = { + .yes_ranges = adxl313_readable_reg_range, + .n_yes_ranges =ARRAY_SIZE (adxl313_readable_reg_range) +}; +EXPORT_SYMBOL_GPL (adxl313_readable_regs_table); + +const struct regmap_range adxl313_writable_reg_range[] = { +regmap_reg_range (ADXL313_REG_SOFT_RESET ,ADXL313_REG_SOFT_RESET ), +regmap_reg_range (ADXL313_REG_OFS_AXIS (0 ),ADXL313_REG_OFS_AXIS (2 )), +regmap_reg_range (ADXL313_REG_THRESH_ACT ,ADXL313_REG_ACT_INACT_CTL ), +regmap_reg_range (ADXL313_REG_BW_RATE ,ADXL313_REG_INT_MAP ), +regmap_reg_range (ADXL313_REG_DATA_FORMAT ,ADXL313_REG_DATA_FORMAT ), +regmap_reg_range (ADXL313_REG_FIFO_CTL ,ADXL313_REG_FIFO_CTL ) +}; + +const struct regmap_access_table adxl313_writable_regs_table = { + .yes_ranges = adxl313_writable_reg_range, + .n_yes_ranges =ARRAY_SIZE (adxl313_writable_reg_range) +}; +EXPORT_SYMBOL_GPL (adxl313_writable_regs_table); + +struct adxl313_data { +struct regmap *regmap; +struct mutex lock;/* lock to protect transf_buf */ +__le16 transf_buf____cacheline_aligned ; +}; + +static const int adxl313_odr_freqs[][2 ] = { + [0 ] = {6 ,250000 }, + [1 ] = {12 ,500000 }, + [2 ] = {25 ,0 }, + [3 ] = {50 ,0 }, + [4 ] = {100 ,0 }, + [5 ] = {200 ,0 }, + [6 ] = {400 ,0 }, + [7 ] = {800 ,0 }, + [8 ] = {1600 ,0 }, + [9 ] = {3200 ,0 }, +}; + +#define ADXL313_ACCEL_CHANNEL (index, addr, axis) { \ + .type = IIO_ACCEL, \ + .address = addr, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_CALIBBIAS), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .info_mask_shared_by_type_available = \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 13, \ + .storagebits = 16, \ + .endianness = IIO_LE, \ + }, \ +} + +static const struct iio_chan_spec adxl313_channels[] = { +ADXL313_ACCEL_CHANNEL (0 ,ADXL313_REG_DATAX ,X ), +ADXL313_ACCEL_CHANNEL (1 ,ADXL313_REG_DATAY ,Y ), +ADXL313_ACCEL_CHANNEL (2 ,ADXL313_REG_DATAZ ,Z ), +}; + +static int adxl313_set_odr (struct adxl313_data *data, +unsigned int freq1,unsigned int freq2) +{ +unsigned int i; + +for (i =0 ; i <ARRAY_SIZE (adxl313_odr_freqs); i++) { +if (adxl313_odr_freqs[i][0 ] == freq1 && + adxl313_odr_freqs[i][1 ] == freq2) +break ; + } + +if (i ==ARRAY_SIZE (adxl313_odr_freqs)) +return -EINVAL ; + +return regmap_update_bits (data->regmap,ADXL313_REG_BW_RATE , +ADXL313_RATE_MSK , +FIELD_PREP (ADXL313_RATE_MSK , +ADXL313_RATE_BASE + i)); +} + +static int adxl313_read_axis (struct adxl313_data *data, +struct iio_chan_spec const *chan) +{ +int ret; + +mutex_lock (&data->lock); + + ret =regmap_bulk_read (data->regmap, + chan->address, + &data->transf_buf,2 ); +if (ret) + goto unlock_ret; + + ret =le16_to_cpu (data->transf_buf); + +unlock_ret: +mutex_unlock (&data->lock); +return ret; +} + +static int adxl313_read_freq_avail (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +const int **vals,int *type,int *length, +long mask) +{ +switch (mask) { +case IIO_CHAN_INFO_SAMP_FREQ : + *vals = (const int *)adxl313_odr_freqs; + *length =ARRAY_SIZE (adxl313_odr_freqs) *2 ; + *type =IIO_VAL_INT_PLUS_MICRO ; +return IIO_AVAIL_LIST ; +default : +return -EINVAL ; + } +} + +static int adxl313_read_raw (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +int *val,int *val2,long mask) +{ +struct adxl313_data *data =iio_priv (indio_dev); +unsigned int regval; +int ret; + +switch (mask) { +case IIO_CHAN_INFO_RAW : + ret =adxl313_read_axis (data, chan); +if (ret <0 ) +return ret; + + *val =sign_extend32 (ret, chan->scan_type.realbits -1 ); +return IIO_VAL_INT ; +case IIO_CHAN_INFO_SCALE : + *val =0 ; + *val2 =ADXL313_NSCALE ; +return IIO_VAL_INT_PLUS_NANO ; +case IIO_CHAN_INFO_CALIBBIAS : + ret =regmap_read (data->regmap, +ADXL313_REG_OFS_AXIS (chan->scan_index), + ®val); +if (ret) +return ret; + +/* +* 8-bit resolution at +/- 0.5g, that is 4x accel data scale +* factor at full resolution +*/ + *val =sign_extend32 (regval,7 ) *4 ; +return IIO_VAL_INT ; +case IIO_CHAN_INFO_SAMP_FREQ : + ret =regmap_read (data->regmap,ADXL313_REG_BW_RATE , ®val); +if (ret) +return ret; + + ret =FIELD_GET (ADXL313_RATE_MSK , regval) -ADXL313_RATE_BASE ; + *val = adxl313_odr_freqs[ret][0 ]; + *val2 = adxl313_odr_freqs[ret][1 ]; +return IIO_VAL_INT_PLUS_MICRO ; +default : +return -EINVAL ; + } +} + +static int adxl313_write_raw (struct iio_dev *indio_dev, +struct iio_chan_spec const *chan, +int val,int val2,long mask)drivers/iio/accel/adxl313_core.c line 206
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drivers/iio/accel/adxl313_core.c new file +10
-0+{ +struct adxl313_data *data =iio_priv (indio_dev); + +switch (mask) { +case IIO_CHAN_INFO_CALIBBIAS : +/* +* 8-bit resolution at +/- 0.5g, that is 4x accel data scale +* factor at full resolution +*/ +if (val >127 *4 || val <-128 *4 )if (
clamp_val(val, ...)!= val) ?
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But actually i would like rather to see predefined macro
is_in_range()inminmax.h.
Yeah, a is_in_range() macro would be nice for this case, but anyway, I think the clamp_val is a cleaner solution.
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drivers/iio/accel/adxl313_core.c new file +115
-0+return -EINVAL ; + +return regmap_write (data->regmap, +ADXL313_REG_OFS_AXIS (chan->scan_index), + val /4 ); +case IIO_CHAN_INFO_SAMP_FREQ : +return adxl313_set_odr (data, val, val2); +default : +return -EINVAL ; + } +} + +static const struct iio_info adxl313_info = { + .read_raw = adxl313_read_raw, + .write_raw = adxl313_write_raw, + .read_avail = adxl313_read_freq_avail +}; + +static int adxl313_setup (struct device *dev,struct adxl313_data *data, +int (*interface_specific_setup)(struct device *, +struct regmap *)) +{ +unsigned int regval; +int ret; + + ret =regmap_read (data->regmap,ADXL313_REG_DEVID0 , ®val); +if (ret) +return ret; + +if (interface_specific_setup) { + ret =interface_specific_setup (dev, data->regmap); +if (ret) +return ret; + } + +if (regval !=ADXL313_DEVID0 ) { +dev_err (dev,"Invalid manufacturer ID: 0x%02x\n" , regval); +return -ENODEV ; + } + + ret =regmap_read (data->regmap,ADXL313_REG_DEVID1 , ®val); +if (ret) +return ret; + +if (regval !=ADXL313_DEVID1 ) { +dev_err (dev,"Invalid mems ID: 0x%02x\n" , regval); +return -ENODEV ; + } + + ret =regmap_read (data->regmap,ADXL313_REG_PARTID , ®val); +if (ret) +return ret; + +if (regval !=ADXL313_PARTID ) { +dev_err (dev,"Invalid device ID: 0x%02x\n" , regval); +return -ENODEV ; + } + +/* Sets the range to +/- 4g */ + ret =regmap_update_bits (data->regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_RANGE_MSK , +FIELD_PREP (ADXL313_RANGE_MSK , +ADXL313_RANGE_4G )); +if (ret) +return ret; + +/* Enables full resolution */ + ret =regmap_update_bits (data->regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_FULL_RES ,ADXL313_FULL_RES ); +if (ret) +return ret; + +/* Enables measurement mode */ +return regmap_update_bits (data->regmap,ADXL313_REG_POWER_CTL , +ADXL313_POWER_CTL_MSK , +ADXL313_MEASUREMENT_MODE ); +} + +int adxl313_core_probe (struct device *dev, +struct regmap *regmap, +const char *name, +int (*interface_specific_setup)(struct device *, +struct regmap *)) +{ +struct adxl313_data *data; +struct iio_dev *indio_dev; +int ret; + + indio_dev =devm_iio_device_alloc (dev,sizeof (*data)); +if (!indio_dev) +return -ENOMEM ; + + data =iio_priv (indio_dev); + data->regmap = regmap; +mutex_init (&data->lock); + + indio_dev->name = name; + indio_dev->info = &adxl313_info; + indio_dev->modes =INDIO_DIRECT_MODE ; + indio_dev->channels = adxl313_channels; + indio_dev->num_channels =ARRAY_SIZE (adxl313_channels); + + ret =adxl313_setup (dev, data, interface_specific_setup); +if (ret) { +dev_err (dev,"ADXL313 setup failed\n" ); +return ret; + } + +return devm_iio_device_register (dev, indio_dev); +} +EXPORT_SYMBOL_GPL (adxl313_core_probe); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer core driver" ); +MODULE_LICENSE ("GPL v2" );drivers/iio/accel/adxl313_i2c.c new file +17
-0@@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "adxl313.h" + +static const struct regmap_config adxl313_i2c_regmap_config = { + .reg_bits =8 ,
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drivers/iio/accel/adxl313_i2c.c line 21
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drivers/iio/accel/adxl313_i2c.c new file +4
-0+ .val_bits = 8, + .rd_table = &adxl313_readable_regs_table, + .wr_table = &adxl313_writable_regs_table, + .max_register = 0x39Leave comma here
I'll add them for the v3.
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drivers/iio/accel/adxl313_i2c.c new file +44
-0+}; + +static int adxl313_i2c_probe (struct i2c_client *client) +{ +struct regmap *regmap; + + regmap =devm_regmap_init_i2c (client, &adxl313_i2c_regmap_config); +if (IS_ERR (regmap)) { +dev_err (&client->dev,"Error initializing i2c regmap: %ld\n" , +PTR_ERR (regmap)); +return PTR_ERR (regmap); + } + +return adxl313_core_probe (&client->dev, regmap, client->name,NULL ); +} + +static const struct i2c_device_id adxl313_i2c_id[] = { + {"adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (i2c, adxl313_i2c_id); + +static const struct of_device_id adxl313_of_match[] = { + { .compatible ="adi,adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (of, adxl313_of_match); + +static struct i2c_driver adxl313_i2c_driver = { + .driver = { + .name ="adxl313_i2c" , + .of_match_table = adxl313_of_match, + }, + .probe_new = adxl313_i2c_probe, + .id_table = adxl313_i2c_id +}; + +module_i2c_driver (adxl313_i2c_driver); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer I2C driver" ); +MODULE_LICENSE ("GPL v2" );drivers/iio/accel/adxl313_spi.c new file +13
-0@@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* +* ADXL313 3-Axis Digital Accelerometer +* +* Copyright (c) 2021 Lucas Stankus <[email protected]> +* +* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf +*/ + +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> +drivers/iio/accel/adxl313_spi.c line 23
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drivers/iio/accel/adxl313_spi.c new file +10
-0+#include "adxl313.h" + +static const struct regmap_config adxl313_spi_regmap_config = { + .reg_bits =8 , + .val_bits =8 , + .rd_table = &adxl313_readable_regs_table, + .wr_table = &adxl313_writable_regs_table, + .max_register =0x39 , +/* Setting bits 7 and 6 enables multiple-byte read */ + .read_flag_mask =BIT (7 ) |BIT (6 )Ditto
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drivers/iio/accel/adxl313_spi.c new file +62
-1+}; + +static int adxl313_spi_setup (struct device *dev,struct regmap *regmap) +{ + struct spi_device *spi = container_of(dev, struct spi_device, dev); +int ret; + +if (spi->mode &SPI_3WIRE ) { + ret =regmap_write (regmap,ADXL313_REG_DATA_FORMAT , +ADXL313_SPI_3WIRE ); +if (ret) +return ret; + } + +return regmap_update_bits (regmap,ADXL313_REG_POWER_CTL , +ADXL313_I2C_DISABLE ,ADXL313_I2C_DISABLE ); +} + +static int adxl313_spi_probe (struct spi_device *spi) +{ +const struct spi_device_id *id =spi_get_device_id (spi); +struct regmap *regmap; + + regmap =devm_regmap_init_spi (spi, &adxl313_spi_regmap_config); +if (IS_ERR (regmap)) { +dev_err (&spi->dev,"Error initializing spi regmap: %ld\n" , +PTR_ERR (regmap)); +return PTR_ERR (regmap); + } + +return adxl313_core_probe (&spi->dev, regmap, id->name, + &adxl313_spi_setup); +} + +static const struct spi_device_id adxl313_spi_id[] = { + {"adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (spi, adxl313_spi_id); + +static const struct of_device_id adxl313_of_match[] = { + { .compatible ="adi,adxl313" }, + { } +}; + +MODULE_DEVICE_TABLE (of, adxl313_of_match); + +static struct spi_driver adxl313_spi_driver = { + .driver = { + .name ="adxl313_spi" , + .of_match_table = adxl313_of_match, + }, + .probe = adxl313_spi_probe, + .id_table = adxl313_spi_id +}; + +module_spi_driver (adxl313_spi_driver); + +MODULE_AUTHOR ("Lucas Stankus <[email protected]>" ); +MODULE_DESCRIPTION ("ADXL313 3-Axis Digital Accelerometer SPI driver" ); +MODULE_LICENSE ("GPL v2" ); --Quoted 2 lines
2.32.0
--
With Best Regards,
Andy Shevchenko
Jonathan Cameron
maintainerRe: [PATCH v2 2/2] iio: accel: Add driver support for ADXL313
Quoted 49 lines · On Fri, 6 Aug 2021 21:22:46 -0300 Lucas Stankus <[email protected]>…
Quoted 33 lines · Andy Shevchenko
Quoted 29 lines · Lucas Stankus
ADXL313 is a small, thin, low power, 3-axis accelerometer with high resolution measurement up to +/-4g. It includes an integrated 32-level FIFO and has activity and inactivity sensing capabilities.
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
Signed-off-by Lucas Stankus <[email protected]>--- MAINTAINERS | 9 + drivers/iio/accel/Kconfig | 29 +++ drivers/iio/accel/Makefile | 3 + drivers/iio/accel/adxl313.h | 63 ++++++ drivers/iio/accel/adxl313_core.c | 321 +++++++++++++++++++++++++++++++ drivers/iio/accel/adxl313_i2c.c | 65 +++++++ drivers/iio/accel/adxl313_spi.c | 85 ++++++++ 7 files changed, 575 insertions(+) create mode 100644 drivers/iio/accel/adxl313.h create mode 100644 drivers/iio/accel/adxl313_core.c create mode 100644 drivers/iio/accel/adxl313_i2c.c create mode 100644 drivers/iio/accel/adxl313_spi.cMAINTAINERS +0
-0@@ -585,6 +585,15 @@ L: [email protected] S: Maintained F: drivers/platform/x86/adv_swbutton.cQuoted 13 lines
MAINTAINERS L: [email protected] · line 595
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MAINTAINERS +8
-0+ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER +M: Lucas Stankus <[email protected]> +S: Supported +F: Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml +F: drivers/iio/accel/adxl313.h +F: drivers/iio/accel/adxl313_core.c +F: drivers/iio/accel/adxl313_i2c.c +F: drivers/iio/accel/adxl313_spi.cadxl313*?
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Didn't know this would work, but I think I prefer the way it is now. Are you proposing this as a suggestion or more of a change request?
It's a bit neater and very unlikely we'll get a clash on that wild card in the long run, so I'd 'slightly' prefer this as well.
...
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+/*
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MAINTAINERS +4
-0+ * Scale for any g range is given in datasheet as + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2 + */ +#define ADXL313_NSCALE 9576806
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Is it in nanonewtons? Perhaps add a suffix
_nN?It's actually in meters per second squared, so I couldn't come up with a good suffix. Do you have any suggestions?
Easy. Don't have a #define :)
In all seriousness it isn't a 'magic' number, it's an actual real world value, so move the comment down to where it's used and put the number directly were it is needed.
Jonathan