[PATCH v7 0/8] iio: accel: adxl313: add power-save on activity/inactivity

[PATCH v7 0/8] iio: accel: adxl313: add power-save on activity/inactivity

[Lothar Rubusch]

The patch set covers the following topics:
- add debug register and regmap cache
- prepare iio channel scan_type and scan_index
- prepare interrupt handling
- implement fifo with watermark
- add activity/inactivity together with auto-sleep with link bit
- add ac coupled activity/inactivity, integrate with auto-sleep and link bit
- documentation

Sorry for the fuzz: when I was about to rebase for submitting I
noticed Jonathan actually already applied parts of this. I'd recommend
to consider v6 rather over v5.

Since activity and inactivity here are implemented covering all axis, I
assumed x&y&z and x|y|z, respectively. Thus the driver uses a fake
channel for activity/inactiviy. AC-coupling is similar to other Analog Device
accelerometers, so MAG_ADAPTIVE events are chosen. Combinations are
documented and functionality tested and verified working.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
v6 -> v7:
- [PATCH v6 3/8]: prefix function `_get_int_type()`
- remove `_read/write_mag_value()`, move their code into calling function
  and allow one level of nested switch/case according to discussion with
  Jonathan
- rework switch/case separatation

v5 -> v6:
- `adxl313_core_probe()`: change conditional logic for evaluation of
  `int_line`
- `adxl313_core_probe()`: add helper function `_get_int_type()` to simplify
  logic
- `adxl313_is_act_inact_en()`: remove blank line; make variable `axis_en` a
  bool
- `adxl313_is_act_inact_ac()`: removal of ',' in comment
- `adxl313_set_act_inact_linkbit()`: regroup logic expressions
- `adxl313_set_act_inact_en()`: change comment style, and rephrase
- `adxl313_read/write_mag_config()`, `adxl313_read/write_mag_value()` and
  `_adxl313_read/write_mag_value()`: avoid nested switch/case statements,
  add helper functions from start and populate them incrementallay
- `adxl313_set_act_inact_ac()`: move AC-coupling code into a separate
  helper
- [PATCH v5 1/8], [PATCH v5 2/8], [PATCH v5 6/8] and [PATCH v5 8/8]: set
  "Reviewed-by:.."

v4 -> v5:
- [v4 01/11]: applied - debug register                                          
- [v4 03/11]: applied w/ changed commit message - regmap cache                  
- refrase all commit messages                                                   
- merge patches [v4 02/11] [v4 05/11] and [v4 06/11]                            
- add ADXL313_REG_INT_SOURCE to the initial regmap cache definition             
- `adxl313_set_watermark()`: replace plain hex numbers by defined bit masks     
- `adxl313_set_watermark()`: replace `regmap_update_bits()` by
  `regmap_set_bits()`
- `adxl313_get_samples()`: remove initialization of variable `samples`          
- `adxl313_buffer_postenable()`: add comment on turning off measurment          
- `adxl313_push_event()`: move WATERMARK separate out, focus on pushing events  
- `adxl313_irq_handler()`: add comment on draining the FIFO                     
- `adxl313_push_event()`: remove missleading comment on return statement        
- `adxl313_is_act_inact_en()`: If it's false, it will be false anyway -
  simplified now
- change order in multiplication with unit: `val * MICRO` which is read
  more naturally
- `adxl313_is_act_inact_en()`: remove check for ADXL313_ACTIVITY in the
  activity patch
- `adxl313_write_event_value()`: remove the general turning off measurement mode
- `adxl313_set_inact_time_s()`: replace plain number 255 by U8_MAX              
- `adxl313_read/write_event_config()`: encapsulate duplicate code into
  `adxl313_read/write_mag_config()`
- `adxl313_read/write_event_value()`: encapsulate duplicate code into
  `adxl313_read/write_mag_value()`
- `adxl313_is_act_inact_en()`: apply switch/case rather than if/else for
  readability; factor out variable `coupling`; convert all remaining `_en`
  variables there to bool, such that a negative error is evaluated from a
  `ret`, and     logic operates with `_en` variables
- `adxl313_set_act_inact_en()`: major rework due to issues discovered by
  automated testing (also affects related functions)
- fix kernel-doc issues 

v3 -> v4:
- squash patches [v3 02/12 + 03/12]: buffer usage into the patch that adds buffered support
- squash patches [v3 07/12 + 08/12]: interrupt handler with watermark implementation
- add patch: (in)activity / AC coupled as `MAG_ADAPTIVE` event
- `ADXL313_MEASUREMENT_MODE`: adjust commit message on removal of define and adding measurement enable function
- remove irq variable from driver data struct, make it a local variable
- `adxl313_core_probe()`: flip logic to condition `int_line != ADXL313_INT_NONE`
- `adxl313_core_probe()`: change mapping interrupts from 0xff to an explicit local mask
- `adxl313_core_probe()`: add comment on FIFO bypass mode
- reduce odd selection of headers to add [`adxl313_core.c`]
- `adxl313_set_fifo()`: this function was turning measurement off/on before changing `fifo_mode`,
   called in postenable and predisable this firstly excluded setting of interrupts, and secondly
   still configured watermark where unnecessary, this function was thus removed (covers unhandled
   return value, and refactoring of function parameters)
- `adxl313_fifo_transfer()`: simplify computation of `sizeof(i*count/2)`
- `adxl313_irq_handler()`: make call of `adxl313_reset_fifo()` conditional to OVERRUN one patch earlier
- includes: rework adding included headers
- activity: change to work with or'd axis and related changes to the fake channel and arrays
- `adxl313_set_act_inact_en()`: generally turn off measurement when adjusting config
  activity/inactivity related config registers, turn measurement on after
- doc: adjust code block highlighting and remove links

v2 -> v3:
- verify keeping trailing comma when it's multi-line assignment [v1 02/12]
- `adxl313_set_fifo()`: verify have two on one line to make it easier to read [v1 07/12]
- `adxl313_fifo_transfer()`: verify removal of useless initialization of ret [v1 07/12]
- `adxl313_fifo_transfer()`: verify usage of array_size() from overflow.h [v1 07/12]
- `adxl313_fifo_transfer()`: verify return 0 here [v1 07/12]
- `adxl313_irq_handler()`: verify "Why do we need the label?" / moving the call under the conditional [v1 07/12]
- verify reorganization of half condition for Activity [v1 09/12] and Inactivity [v1 10/12]
- verify usage of MICRO instead of 1000000
- `adxl313_is_act_inact_en()`: restructure according to return logic value, or negative error
- `adxl313_set_act_inact_en()`: restructure function, use regmap_assign_bits()
- `adxl313_set_act_inact_en()`: verify makeing it a logical split [v1 11/12]
- `adxl313_fifo_transfer()`: change iterator variable type from int to unsigned int [v2 07/12]
- `adxl313_fifo_reset()`: add comment on why reset status registers does not do error check ("At least comment...") [v2 07/12]
- `adxl313_fifo_push()`: change iterator variable from int to unsigned int [v2 08/12]
- `adxl313_fifo_push()`: remove duplicate check for samples being <0 [v2 08/12]
- apply `regmap_assign_bits()` in several places to replace regmap_update_bits() depending on bools
- `adxl313_set_watermark()`: rename mask variable to make it more comprehensive
- removal of duplicate blanks in various places (sry, my keyboard died) [v1 07/12]

v1 -> v2:
- usage of units.h
- simplify approach for return values
---

Lothar Rubusch (8):
  iio: accel: adxl313: make use of regmap cache
  iio: accel: adxl313: add function to enable measurement
  iio: accel: adxl313: add buffered FIFO watermark with interrupt
    handling
  iio: accel: adxl313: add activity sensing
  iio: accel: adxl313: add inactivity sensing
  iio: accel: adxl313: implement power-save on inactivity
  iio: accel: adxl313: add AC coupled activity/inactivity events
  docs: iio: add ADXL313 accelerometer

 Documentation/iio/adxl313.rst    | 289 ++++++++++
 Documentation/iio/index.rst      |   1 +
 drivers/iio/accel/adxl313.h      |  33 +-
 drivers/iio/accel/adxl313_core.c | 912 ++++++++++++++++++++++++++++++-
 drivers/iio/accel/adxl313_i2c.c  |   6 +
 drivers/iio/accel/adxl313_spi.c  |   6 +
 6 files changed, 1236 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/iio/adxl313.rst


base-commit: 42498420746a4db923f03d048a0ebc9bd2371f56
prerequisite-patch-id: efe11e81ad33f9728664108cf9670e2811d67e38
-- 
2.39.5

[PATCH v7 1/8] iio: accel: adxl313: make use of regmap cache

[Lothar Rubusch]

Setup regmap cache to cache register configuration, reducing bus traffic
for repeated accesses to non volatile registers.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |  3 +++
 drivers/iio/accel/adxl313_core.c | 18 ++++++++++++++++++
 drivers/iio/accel/adxl313_i2c.c  |  6 ++++++
 drivers/iio/accel/adxl313_spi.c  |  6 ++++++
 4 files changed, 33 insertions(+)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index 72f624af4686..2bc86ac8ffd4 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -22,6 +22,7 @@
 #define ADXL313_REG_BW_RATE		0x2C
 #define ADXL313_REG_POWER_CTL		0x2D
 #define ADXL313_REG_INT_MAP		0x2F
+#define ADXL313_REG_INT_SOURCE		0x30
 #define ADXL313_REG_DATA_FORMAT		0x31
 #define ADXL313_REG_DATA_AXIS(index)	(0x32 + ((index) * 2))
 #define ADXL313_REG_FIFO_CTL		0x38
@@ -54,6 +55,8 @@ extern const struct regmap_access_table adxl312_writable_regs_table;
 extern const struct regmap_access_table adxl313_writable_regs_table;
 extern const struct regmap_access_table adxl314_writable_regs_table;
 
+bool adxl313_is_volatile_reg(struct device *dev, unsigned int reg);
+
 enum adxl313_device_type {
 	ADXL312,
 	ADXL313,
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index 8996180f1e18..dc5f04b17b29 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -46,6 +46,24 @@ const struct regmap_access_table adxl314_readable_regs_table = {
 };
 EXPORT_SYMBOL_NS_GPL(adxl314_readable_regs_table, "IIO_ADXL313");
 
+bool adxl313_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case ADXL313_REG_DATA_AXIS(0):
+	case ADXL313_REG_DATA_AXIS(1):
+	case ADXL313_REG_DATA_AXIS(2):
+	case ADXL313_REG_DATA_AXIS(3):
+	case ADXL313_REG_DATA_AXIS(4):
+	case ADXL313_REG_DATA_AXIS(5):
+	case ADXL313_REG_FIFO_STATUS:
+	case ADXL313_REG_INT_SOURCE:
+		return true;
+	default:
+		return false;
+	}
+}
+EXPORT_SYMBOL_NS_GPL(adxl313_is_volatile_reg, "IIO_ADXL313");
+
 static int adxl312_check_id(struct device *dev,
 			    struct adxl313_data *data)
 {
diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
index dfa51860cd83..b67ff0b4dc54 100644
--- a/drivers/iio/accel/adxl313_i2c.c
+++ b/drivers/iio/accel/adxl313_i2c.c
@@ -21,6 +21,8 @@ static const struct regmap_config adxl31x_i2c_regmap_config[] = {
 		.rd_table	= &adxl312_readable_regs_table,
 		.wr_table	= &adxl312_writable_regs_table,
 		.max_register	= 0x39,
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 	[ADXL313] = {
 		.reg_bits	= 8,
@@ -28,6 +30,8 @@ static const struct regmap_config adxl31x_i2c_regmap_config[] = {
 		.rd_table	= &adxl313_readable_regs_table,
 		.wr_table	= &adxl313_writable_regs_table,
 		.max_register	= 0x39,
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 	[ADXL314] = {
 		.reg_bits	= 8,
@@ -35,6 +39,8 @@ static const struct regmap_config adxl31x_i2c_regmap_config[] = {
 		.rd_table	= &adxl314_readable_regs_table,
 		.wr_table	= &adxl314_writable_regs_table,
 		.max_register	= 0x39,
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 };
 
diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
index 17b25f3b2027..cb6a676ec7a0 100644
--- a/drivers/iio/accel/adxl313_spi.c
+++ b/drivers/iio/accel/adxl313_spi.c
@@ -24,6 +24,8 @@ static const struct regmap_config adxl31x_spi_regmap_config[] = {
 		.max_register	= 0x39,
 		/* Setting bits 7 and 6 enables multiple-byte read */
 		.read_flag_mask	= BIT(7) | BIT(6),
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 	[ADXL313] = {
 		.reg_bits	= 8,
@@ -33,6 +35,8 @@ static const struct regmap_config adxl31x_spi_regmap_config[] = {
 		.max_register	= 0x39,
 		/* Setting bits 7 and 6 enables multiple-byte read */
 		.read_flag_mask	= BIT(7) | BIT(6),
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 	[ADXL314] = {
 		.reg_bits	= 8,
@@ -42,6 +46,8 @@ static const struct regmap_config adxl31x_spi_regmap_config[] = {
 		.max_register	= 0x39,
 		/* Setting bits 7 and 6 enables multiple-byte read */
 		.read_flag_mask	= BIT(7) | BIT(6),
+		.volatile_reg	= adxl313_is_volatile_reg,
+		.cache_type	= REGCACHE_MAPLE,
 	},
 };
 
-- 
2.39.5

[PATCH v7 2/8] iio: accel: adxl313: add function to enable measurement

[Lothar Rubusch]

Refactor the control of measurement and standby modes for the sensor.
Instead of directly writing to the register, encapsulate this operation
in a dedicated function that handles enabling and disabling measurement.
This approach will reduce code duplication wherever sensor configuration
changes are required. In subsequent patches, measurement mode will be
set to standby as part of this process.

Additionally, simplify the control mask to include only the measurement
bit. The sleep bit governs a different behavior—putting the sensor into
sleep mode, not just standby for configuration—and is currently unused.
Therefore, there's no need to include both the sleep and measurement
bits in the same mask.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |  3 +--
 drivers/iio/accel/adxl313_core.c | 10 +++++++---
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index 2bc86ac8ffd4..6958a00f5e8f 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -37,8 +37,7 @@
 #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_POWER_CTL_MSK		BIT(3)
 
 #define ADXL313_RANGE_MSK		GENMASK(1, 0)
 #define ADXL313_RANGE_MAX		3
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index dc5f04b17b29..1be4e867f4b2 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -64,6 +64,12 @@ bool adxl313_is_volatile_reg(struct device *dev, unsigned int reg)
 }
 EXPORT_SYMBOL_NS_GPL(adxl313_is_volatile_reg, "IIO_ADXL313");
 
+static int adxl313_set_measure_en(struct adxl313_data *data, bool en)
+{
+	return regmap_assign_bits(data->regmap, ADXL313_REG_POWER_CTL,
+				  ADXL313_POWER_CTL_MSK, en);
+}
+
 static int adxl312_check_id(struct device *dev,
 			    struct adxl313_data *data)
 {
@@ -398,9 +404,7 @@ static int adxl313_setup(struct device *dev, struct adxl313_data *data,
 	}
 
 	/* Enables measurement mode */
-	return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
-				  ADXL313_POWER_CTL_MSK,
-				  ADXL313_MEASUREMENT_MODE);
+	return adxl313_set_measure_en(data, true);
 }
 
 /**
-- 
2.39.5

[PATCH v7 3/8] iio: accel: adxl313: add buffered FIFO watermark with interrupt handling

[Lothar Rubusch]

Cover the following tasks:
- Add scan_mask and scan_index to the IIO channel configuration. The
scan_index sets up buffer usage. According to the datasheet, the ADXL313
uses a 13-bit wide data field in full-resolution mode. Set the
signedness, number of storage bits, and endianness accordingly.

- Parse the devicetree for an optional interrupt line and configure the
interrupt mapping based on its presence. If no interrupt line is
specified, keep the FIFO in bypass mode as currently implemented.

- Set up the interrupt handler. Add register access to detect and
evaluate interrupts. Implement functions to clear status registers and
reset the FIFO.

- Implement FIFO watermark configuration and handling. Allow the
watermark level to be set, evaluate the corresponding interrupt, read
the FIFO contents, and push the data to the IIO channel.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |  22 +++
 drivers/iio/accel/adxl313_core.c | 264 ++++++++++++++++++++++++++++++-
 2 files changed, 280 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index 6958a00f5e8f..4f4a9fd39f6d 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -21,6 +21,7 @@
 #define ADXL313_REG_ACT_INACT_CTL	0x27
 #define ADXL313_REG_BW_RATE		0x2C
 #define ADXL313_REG_POWER_CTL		0x2D
+#define ADXL313_REG_INT_ENABLE		0x2E
 #define ADXL313_REG_INT_MAP		0x2F
 #define ADXL313_REG_INT_SOURCE		0x30
 #define ADXL313_REG_DATA_FORMAT		0x31
@@ -46,6 +47,25 @@
 #define ADXL313_SPI_3WIRE		BIT(6)
 #define ADXL313_I2C_DISABLE		BIT(6)
 
+#define ADXL313_INT_OVERRUN		BIT(0)
+#define ADXL313_INT_WATERMARK		BIT(1)
+#define ADXL313_INT_INACTIVITY		BIT(3)
+#define ADXL313_INT_ACTIVITY		BIT(4)
+#define ADXL313_INT_DREADY		BIT(7)
+
+/* FIFO entries: how many values are stored in the FIFO */
+#define ADXL313_REG_FIFO_STATUS_ENTRIES_MSK	GENMASK(5, 0)
+/* FIFO samples: number of samples needed for watermark (FIFO mode) */
+#define ADXL313_REG_FIFO_CTL_SAMPLES_MSK	GENMASK(4, 0)
+#define ADXL313_REG_FIFO_CTL_MODE_MSK		GENMASK(7, 6)
+
+#define ADXL313_FIFO_BYPASS			0
+#define ADXL313_FIFO_STREAM			2
+
+#define ADXL313_FIFO_SIZE			32
+
+#define ADXL313_NUM_AXIS			3
+
 extern const struct regmap_access_table adxl312_readable_regs_table;
 extern const struct regmap_access_table adxl313_readable_regs_table;
 extern const struct regmap_access_table adxl314_readable_regs_table;
@@ -66,7 +86,9 @@ struct adxl313_data {
 	struct regmap	*regmap;
 	const struct adxl313_chip_info *chip_info;
 	struct mutex	lock; /* lock to protect transf_buf */
+	u8 watermark;
 	__le16		transf_buf __aligned(IIO_DMA_MINALIGN);
+	__le16		fifo_buf[ADXL313_NUM_AXIS * ADXL313_FIFO_SIZE + 1];
 };
 
 struct adxl313_chip_info {
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index 1be4e867f4b2..04ca8491bb5c 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -8,11 +8,23 @@
  */
 
 #include <linux/bitfield.h>
+#include <linux/interrupt.h>
 #include <linux/module.h>
+#include <linux/overflow.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+
 #include "adxl313.h"
 
+#define ADXL313_INT_NONE			U8_MAX
+#define ADXL313_INT1				1
+#define ADXL313_INT2				2
+
+#define ADXL313_REG_XYZ_BASE			ADXL313_REG_DATA_AXIS(0)
+
 static const struct regmap_range adxl312_readable_reg_range[] = {
 	regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_DEVID0),
 	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
@@ -195,9 +207,10 @@ static const int adxl313_odr_freqs[][2] = {
 	[9] = { 3200, 0 },
 };
 
-#define ADXL313_ACCEL_CHANNEL(index, axis) {				\
+#define ADXL313_ACCEL_CHANNEL(index, reg, axis) {			\
 	.type = IIO_ACCEL,						\
-	.address = index,						\
+	.scan_index = (index),						\
+	.address = (reg),						\
 	.modified = 1,							\
 	.channel2 = IIO_MOD_##axis,					\
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
@@ -207,14 +220,26 @@ static const int adxl313_odr_freqs[][2] = {
 	.info_mask_shared_by_type_available =				\
 		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
 	.scan_type = {							\
+		.sign = 's',						\
 		.realbits = 13,						\
+		.storagebits = 16,					\
+		.endianness = IIO_BE,					\
 	},								\
 }
 
+enum adxl313_chans {
+	chan_x, chan_y, chan_z,
+};
+
 static const struct iio_chan_spec adxl313_channels[] = {
-	ADXL313_ACCEL_CHANNEL(0, X),
-	ADXL313_ACCEL_CHANNEL(1, Y),
-	ADXL313_ACCEL_CHANNEL(2, Z),
+	ADXL313_ACCEL_CHANNEL(0, chan_x, X),
+	ADXL313_ACCEL_CHANNEL(1, chan_y, Y),
+	ADXL313_ACCEL_CHANNEL(2, chan_z, Z),
+};
+
+static const unsigned long adxl313_scan_masks[] = {
+	BIT(chan_x) | BIT(chan_y) | BIT(chan_z),
+	0
 };
 
 static int adxl313_set_odr(struct adxl313_data *data,
@@ -345,6 +370,173 @@ static int adxl313_write_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int adxl313_set_watermark(struct iio_dev *indio_dev, unsigned int value)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+	int ret;
+
+	value = min(value, ADXL313_FIFO_SIZE - 1);
+
+	ret = adxl313_set_measure_en(data, false);
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(data->regmap, ADXL313_REG_FIFO_CTL,
+				 ADXL313_REG_FIFO_CTL_MODE_MSK, value);
+	if (ret)
+		return ret;
+
+	data->watermark = value;
+
+	ret = regmap_set_bits(data->regmap, ADXL313_REG_INT_ENABLE,
+			      ADXL313_INT_WATERMARK);
+	if (ret)
+		return ret;
+
+	return adxl313_set_measure_en(data, true);
+}
+
+static int adxl313_get_samples(struct adxl313_data *data)
+{
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(data->regmap, ADXL313_REG_FIFO_STATUS, &regval);
+	if (ret)
+		return ret;
+
+	return FIELD_GET(ADXL313_REG_FIFO_STATUS_ENTRIES_MSK, regval);
+}
+
+static int adxl313_fifo_transfer(struct adxl313_data *data, int samples)
+{
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < samples; i++) {
+		ret = regmap_bulk_read(data->regmap, ADXL313_REG_XYZ_BASE,
+				       data->fifo_buf + (i * ADXL313_NUM_AXIS),
+				       sizeof(data->fifo_buf[0]) * ADXL313_NUM_AXIS);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * adxl313_fifo_reset() - Reset the FIFO and interrupt status registers.
+ * @data: The device data.
+ *
+ * Reset the FIFO status registers. Reading out status registers clears the
+ * FIFO and interrupt configuration. Thus do not evaluate regmap return values.
+ * Ignore particular read register content. Register content is not processed
+ * any further. Therefore the function returns void.
+ */
+static void adxl313_fifo_reset(struct adxl313_data *data)
+{
+	unsigned int regval;
+	int samples;
+
+	adxl313_set_measure_en(data, false);
+
+	samples = adxl313_get_samples(data);
+	if (samples > 0)
+		adxl313_fifo_transfer(data, samples);
+
+	regmap_read(data->regmap, ADXL313_REG_INT_SOURCE, &regval);
+
+	adxl313_set_measure_en(data, true);
+}
+
+static int adxl313_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+	int ret;
+
+	/* Set FIFO modes with measurement turned off, according to datasheet */
+	ret = adxl313_set_measure_en(data, false);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, ADXL313_REG_FIFO_CTL,
+			   FIELD_PREP(ADXL313_REG_FIFO_CTL_SAMPLES_MSK,	data->watermark) |
+			   FIELD_PREP(ADXL313_REG_FIFO_CTL_MODE_MSK, ADXL313_FIFO_STREAM));
+	if (ret)
+		return ret;
+
+	return adxl313_set_measure_en(data, true);
+}
+
+static int adxl313_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = adxl313_set_measure_en(data, false);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, ADXL313_REG_FIFO_CTL,
+			   FIELD_PREP(ADXL313_REG_FIFO_CTL_MODE_MSK, ADXL313_FIFO_BYPASS));
+
+	ret = regmap_write(data->regmap, ADXL313_REG_INT_ENABLE, 0);
+	if (ret)
+		return ret;
+
+	return adxl313_set_measure_en(data, true);
+}
+
+static const struct iio_buffer_setup_ops adxl313_buffer_ops = {
+	.postenable = adxl313_buffer_postenable,
+	.predisable = adxl313_buffer_predisable,
+};
+
+static int adxl313_fifo_push(struct iio_dev *indio_dev, int samples)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+	unsigned int i;
+	int ret;
+
+	ret = adxl313_fifo_transfer(data, samples);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ADXL313_NUM_AXIS * samples; i += ADXL313_NUM_AXIS)
+		iio_push_to_buffers(indio_dev, &data->fifo_buf[i]);
+
+	return 0;
+}
+
+static irqreturn_t adxl313_irq_handler(int irq, void *p)
+{
+	struct iio_dev *indio_dev = p;
+	struct adxl313_data *data = iio_priv(indio_dev);
+	int samples, int_stat;
+
+	if (regmap_read(data->regmap, ADXL313_REG_INT_SOURCE, &int_stat))
+		return IRQ_NONE;
+
+	if (FIELD_GET(ADXL313_INT_WATERMARK, int_stat)) {
+		samples = adxl313_get_samples(data);
+		if (samples < 0)
+			goto err;
+
+		if (adxl313_fifo_push(indio_dev, samples))
+			goto err;
+	}
+
+	if (FIELD_GET(ADXL313_INT_OVERRUN, int_stat))
+		goto err;
+
+	return IRQ_HANDLED;
+
+err:
+	adxl313_fifo_reset(data);
+
+	return IRQ_HANDLED;
+}
+
 static int adxl313_reg_access(struct iio_dev *indio_dev, unsigned int reg,
 			      unsigned int writeval, unsigned int *readval)
 {
@@ -359,6 +551,7 @@ static const struct iio_info adxl313_info = {
 	.read_raw	= adxl313_read_raw,
 	.write_raw	= adxl313_write_raw,
 	.read_avail	= adxl313_read_freq_avail,
+	.hwfifo_set_watermark = adxl313_set_watermark,
 	.debugfs_reg_access = &adxl313_reg_access,
 };
 
@@ -407,6 +600,19 @@ static int adxl313_setup(struct device *dev, struct adxl313_data *data,
 	return adxl313_set_measure_en(data, true);
 }
 
+static unsigned int adxl313_get_int_type(struct device *dev, int *irq)
+{
+	*irq = fwnode_irq_get_byname(dev_fwnode(dev), "INT1");
+	if (*irq > 0)
+		return ADXL313_INT1;
+
+	*irq = fwnode_irq_get_byname(dev_fwnode(dev), "INT2");
+	if (*irq > 0)
+		return ADXL313_INT2;
+
+	return ADXL313_INT_NONE;
+}
+
 /**
  * adxl313_core_probe() - probe and setup for adxl313 accelerometer
  * @dev:	Driver model representation of the device
@@ -424,7 +630,9 @@ int adxl313_core_probe(struct device *dev,
 {
 	struct adxl313_data *data;
 	struct iio_dev *indio_dev;
-	int ret;
+	u8 int_line;
+	u8 int_map_msk;
+	int irq, ret;
 
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
@@ -441,6 +649,7 @@ int adxl313_core_probe(struct device *dev,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = adxl313_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
+	indio_dev->available_scan_masks = adxl313_scan_masks;
 
 	ret = adxl313_setup(dev, data, setup);
 	if (ret) {
@@ -448,6 +657,49 @@ int adxl313_core_probe(struct device *dev,
 		return ret;
 	}
 
+	int_line = adxl313_get_int_type(dev, &irq);
+	if (int_line == ADXL313_INT_NONE) {
+		/*
+		 * FIFO_BYPASSED mode
+		 *
+		 * When no interrupt lines are specified, the driver falls back
+		 * to use the sensor in FIFO_BYPASS mode. This means turning off
+		 * internal FIFO and interrupt generation (since there is no
+		 * line specified). Unmaskable interrupts such as overrun or
+		 * data ready won't interfere. Even that a FIFO_STREAM mode w/o
+		 * connected interrupt line might allow for obtaining raw
+		 * measurements, a fallback to disable interrupts when no
+		 * interrupt lines are connected seems to be the cleaner
+		 * solution.
+		 */
+		ret = regmap_write(data->regmap, ADXL313_REG_FIFO_CTL,
+				   FIELD_PREP(ADXL313_REG_FIFO_CTL_MODE_MSK,
+					      ADXL313_FIFO_BYPASS));
+		if (ret)
+			return ret;
+	} else {
+		/* FIFO_STREAM mode */
+		int_map_msk = ADXL313_INT_DREADY | ADXL313_INT_ACTIVITY |
+			ADXL313_INT_INACTIVITY | ADXL313_INT_WATERMARK |
+			ADXL313_INT_OVERRUN;
+		ret = regmap_assign_bits(data->regmap, ADXL313_REG_INT_MAP,
+					 int_map_msk, int_line == ADXL313_INT2);
+		if (ret)
+			return ret;
+
+		ret = devm_iio_kfifo_buffer_setup(dev, indio_dev,
+						  &adxl313_buffer_ops);
+		if (ret)
+			return ret;
+
+		ret = devm_request_threaded_irq(dev, irq, NULL,
+						&adxl313_irq_handler,
+						IRQF_SHARED | IRQF_ONESHOT,
+						indio_dev->name, indio_dev);
+		if (ret)
+			return ret;
+	}
+
 	return devm_iio_device_register(dev, indio_dev);
 }
 EXPORT_SYMBOL_NS_GPL(adxl313_core_probe, "IIO_ADXL313");
-- 
2.39.5

[PATCH v7 4/8] iio: accel: adxl313: add activity sensing

[Lothar Rubusch]

Add support for configuring an activity detection threshold. Extend the
interrupt handler to process activity-related interrupts, and provide
functions to set the threshold as well as to enable or disable activity
sensing. Additionally, introduce a virtual channel that represents the
logical AND of the x, y, and z axes in the IIO channel.

This patch serves as a preparatory step; some definitions and functions
introduced here are intended to be extended later to support inactivity
detection.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313_core.c | 306 +++++++++++++++++++++++++++++++
 1 file changed, 306 insertions(+)

diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index 04ca8491bb5c..828b46b2254d 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -13,8 +13,10 @@
 #include <linux/overflow.h>
 #include <linux/property.h>
 #include <linux/regmap.h>
+#include <linux/units.h>
 
 #include <linux/iio/buffer.h>
+#include <linux/iio/events.h>
 #include <linux/iio/kfifo_buf.h>
 
 #include "adxl313.h"
@@ -25,6 +27,21 @@
 
 #define ADXL313_REG_XYZ_BASE			ADXL313_REG_DATA_AXIS(0)
 
+#define ADXL313_ACT_XYZ_EN			GENMASK(6, 4)
+
+/* activity/inactivity */
+enum adxl313_activity_type {
+	ADXL313_ACTIVITY,
+};
+
+static const unsigned int adxl313_act_int_reg[] = {
+	[ADXL313_ACTIVITY] = ADXL313_INT_ACTIVITY,
+};
+
+static const unsigned int adxl313_act_thresh_reg[] = {
+	[ADXL313_ACTIVITY] = ADXL313_REG_THRESH_ACT,
+};
+
 static const struct regmap_range adxl312_readable_reg_range[] = {
 	regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_DEVID0),
 	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
@@ -227,6 +244,15 @@ static const int adxl313_odr_freqs[][2] = {
 	},								\
 }
 
+static const struct iio_event_spec adxl313_activity_events[] = {
+	{
+		.type = IIO_EV_TYPE_MAG,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
+	},
+};
+
 enum adxl313_chans {
 	chan_x, chan_y, chan_z,
 };
@@ -235,6 +261,14 @@ static const struct iio_chan_spec adxl313_channels[] = {
 	ADXL313_ACCEL_CHANNEL(0, chan_x, X),
 	ADXL313_ACCEL_CHANNEL(1, chan_y, Y),
 	ADXL313_ACCEL_CHANNEL(2, chan_z, Z),
+	{
+		.type = IIO_ACCEL,
+		.modified = 1,
+		.channel2 = IIO_MOD_X_OR_Y_OR_Z,
+		.scan_index = -1, /* Fake channel for axis OR'ing */
+		.event_spec = adxl313_activity_events,
+		.num_event_specs = ARRAY_SIZE(adxl313_activity_events),
+	},
 };
 
 static const unsigned long adxl313_scan_masks[] = {
@@ -297,6 +331,81 @@ static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
 	}
 }
 
+static int adxl313_is_act_inact_en(struct adxl313_data *data,
+				   enum adxl313_activity_type type)
+{
+	unsigned int axis_ctrl;
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(data->regmap, ADXL313_REG_ACT_INACT_CTL, &axis_ctrl);
+	if (ret)
+		return ret;
+
+	/* Check if axis for activity are enabled */
+	switch (type) {
+	case ADXL313_ACTIVITY:
+		if (!FIELD_GET(ADXL313_ACT_XYZ_EN, axis_ctrl))
+			return false;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Check if specific interrupt is enabled */
+	ret = regmap_read(data->regmap, ADXL313_REG_INT_ENABLE, &regval);
+	if (ret)
+		return ret;
+
+	return adxl313_act_int_reg[type] & regval;
+}
+
+static int adxl313_set_act_inact_en(struct adxl313_data *data,
+				    enum adxl313_activity_type type,
+				    bool cmd_en)
+{
+	unsigned int axis_ctrl;
+	unsigned int threshold;
+	int ret;
+
+	if (cmd_en) {
+		/* When turning on, check if threshold is valid */
+		ret = regmap_read(data->regmap, adxl313_act_thresh_reg[type],
+				  &threshold);
+		if (ret)
+			return ret;
+
+		if (!threshold) /* Just ignore the command if threshold is 0 */
+			return 0;
+	}
+
+	/* Start modifying configuration registers */
+	ret = adxl313_set_measure_en(data, false);
+	if (ret)
+		return ret;
+
+	/* Enable axis according to the command */
+	switch (type) {
+	case ADXL313_ACTIVITY:
+		axis_ctrl = ADXL313_ACT_XYZ_EN;
+		break;
+	default:
+		return -EINVAL;
+	}
+	ret = regmap_assign_bits(data->regmap, ADXL313_REG_ACT_INACT_CTL,
+				 axis_ctrl, cmd_en);
+	if (ret)
+		return ret;
+
+	/* Enable the interrupt line, according to the command */
+	ret = regmap_assign_bits(data->regmap, ADXL313_REG_INT_ENABLE,
+				 adxl313_act_int_reg[type], cmd_en);
+	if (ret)
+		return ret;
+
+	return adxl313_set_measure_en(data, true);
+}
+
 static int adxl313_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int *val, int *val2, long mask)
@@ -370,6 +479,157 @@ static int adxl313_write_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int adxl313_read_mag_config(struct adxl313_data *data,
+				   enum iio_event_direction dir,
+				   enum adxl313_activity_type type_act)
+{
+	switch (dir) {
+	case IIO_EV_DIR_RISING:
+		return !!adxl313_is_act_inact_en(data, type_act);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_write_mag_config(struct adxl313_data *data,
+				    enum iio_event_direction dir,
+				    enum adxl313_activity_type type_act,
+				    bool state)
+{
+	switch (dir) {
+	case IIO_EV_DIR_RISING:
+		return adxl313_set_act_inact_en(data, type_act, state);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_read_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+
+	switch (type) {
+	case IIO_EV_TYPE_MAG:
+		return adxl313_read_mag_config(data, dir,
+					       ADXL313_ACTIVITY);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_write_event_config(struct iio_dev *indio_dev,
+				      const struct iio_chan_spec *chan,
+				      enum iio_event_type type,
+				      enum iio_event_direction dir,
+				      bool state)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+
+	switch (type) {
+	case IIO_EV_TYPE_MAG:
+		return adxl313_write_mag_config(data, dir,
+						ADXL313_ACTIVITY,
+						state);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_read_mag_value(struct adxl313_data *data,
+				  enum iio_event_direction dir,
+				  enum iio_event_info info,
+				  enum adxl313_activity_type type_act,
+				  int *val, int *val2)
+{
+	unsigned int threshold;
+	int ret;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			ret = regmap_read(data->regmap,
+					  adxl313_act_thresh_reg[type_act],
+					  &threshold);
+			if (ret)
+				return ret;
+			*val = threshold * 15625;
+			*val2 = MICRO;
+			return IIO_VAL_FRACTIONAL;
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_write_mag_value(struct adxl313_data *data,
+				   enum iio_event_direction dir,
+				   enum iio_event_info info,
+				   enum adxl313_activity_type type_act,
+				   int val, int val2)
+{
+	unsigned int regval;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		/* Scale factor 15.625 mg/LSB */
+		regval = DIV_ROUND_CLOSEST(MICRO * val + val2, 15625);
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return regmap_write(data->regmap,
+					    adxl313_act_thresh_reg[type_act],
+					    regval);
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_read_event_value(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum iio_event_type type,
+				    enum iio_event_direction dir,
+				    enum iio_event_info info,
+				    int *val, int *val2)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+
+	switch (type) {
+	case IIO_EV_TYPE_MAG:
+		return adxl313_read_mag_value(data, dir, info,
+					      ADXL313_ACTIVITY,
+					      val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_write_event_value(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir,
+				     enum iio_event_info info,
+				     int val, int val2)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+
+	switch (type) {
+	case IIO_EV_TYPE_MAG:
+		return adxl313_write_mag_value(data, dir, info,
+					       ADXL313_ACTIVITY,
+					       val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
 static int adxl313_set_watermark(struct iio_dev *indio_dev, unsigned int value)
 {
 	struct adxl313_data *data = iio_priv(indio_dev);
@@ -508,6 +768,25 @@ static int adxl313_fifo_push(struct iio_dev *indio_dev, int samples)
 	return 0;
 }
 
+static int adxl313_push_events(struct iio_dev *indio_dev, int int_stat)
+{
+	s64 ts = iio_get_time_ns(indio_dev);
+	int ret = -ENOENT;
+
+	if (FIELD_GET(ADXL313_INT_ACTIVITY, int_stat)) {
+		ret = iio_push_event(indio_dev,
+				     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+							IIO_MOD_X_OR_Y_OR_Z,
+							IIO_EV_TYPE_MAG,
+							IIO_EV_DIR_RISING),
+				     ts);
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
 static irqreturn_t adxl313_irq_handler(int irq, void *p)
 {
 	struct iio_dev *indio_dev = p;
@@ -517,6 +796,16 @@ static irqreturn_t adxl313_irq_handler(int irq, void *p)
 	if (regmap_read(data->regmap, ADXL313_REG_INT_SOURCE, &int_stat))
 		return IRQ_NONE;
 
+	/*
+	 * In cases of sensor events not handled (still not implemented) by
+	 * this driver, the FIFO needs to be drained to become operational
+	 * again. In general the sensor configuration only should issue events
+	 * which were configured by this driver. Anyway a miss-configuration
+	 * easily might end up in a hanging sensor FIFO.
+	 */
+	if (adxl313_push_events(indio_dev, int_stat))
+		goto err;
+
 	if (FIELD_GET(ADXL313_INT_WATERMARK, int_stat)) {
 		samples = adxl313_get_samples(data);
 		if (samples < 0)
@@ -550,6 +839,10 @@ static int adxl313_reg_access(struct iio_dev *indio_dev, unsigned int reg,
 static const struct iio_info adxl313_info = {
 	.read_raw	= adxl313_read_raw,
 	.write_raw	= adxl313_write_raw,
+	.read_event_config = adxl313_read_event_config,
+	.write_event_config = adxl313_write_event_config,
+	.read_event_value = adxl313_read_event_value,
+	.write_event_value = adxl313_write_event_value,
 	.read_avail	= adxl313_read_freq_avail,
 	.hwfifo_set_watermark = adxl313_set_watermark,
 	.debugfs_reg_access = &adxl313_reg_access,
@@ -687,6 +980,19 @@ int adxl313_core_probe(struct device *dev,
 		if (ret)
 			return ret;
 
+		/*
+		 * Reset or configure the registers with reasonable default
+		 * values. As having 0 in most cases may result in undesirable
+		 * behavior if the interrupts are enabled.
+		 */
+		ret = regmap_write(data->regmap, ADXL313_REG_ACT_INACT_CTL, 0x00);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(data->regmap, ADXL313_REG_THRESH_ACT, 0x52);
+		if (ret)
+			return ret;
+
 		ret = devm_iio_kfifo_buffer_setup(dev, indio_dev,
 						  &adxl313_buffer_ops);
 		if (ret)
-- 
2.39.5

[PATCH v7 5/8] iio: accel: adxl313: add inactivity sensing

[Lothar Rubusch]

Enhance the interrupt handler to process inactivity events. Introduce
functions to configure the threshold and period registers for
inactivity detection, as well as to enable or disable the inactivity
feature. Extend the fake IIO channel to handle inactivity events by
combining the x, y, and z axes using a logical AND operation.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |   2 +
 drivers/iio/accel/adxl313_core.c | 110 ++++++++++++++++++++++++++++++-
 2 files changed, 110 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index 4f4a9fd39f6d..d7e8cb44855b 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -18,6 +18,8 @@
 #define ADXL313_REG_SOFT_RESET		0x18
 #define ADXL313_REG_OFS_AXIS(index)	(0x1E + (index))
 #define ADXL313_REG_THRESH_ACT		0x24
+#define ADXL313_REG_THRESH_INACT	0x25
+#define ADXL313_REG_TIME_INACT		0x26
 #define ADXL313_REG_ACT_INACT_CTL	0x27
 #define ADXL313_REG_BW_RATE		0x2C
 #define ADXL313_REG_POWER_CTL		0x2D
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index 828b46b2254d..e904dee4dc2b 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -28,18 +28,22 @@
 #define ADXL313_REG_XYZ_BASE			ADXL313_REG_DATA_AXIS(0)
 
 #define ADXL313_ACT_XYZ_EN			GENMASK(6, 4)
+#define ADXL313_INACT_XYZ_EN			GENMASK(2, 0)
 
 /* activity/inactivity */
 enum adxl313_activity_type {
 	ADXL313_ACTIVITY,
+	ADXL313_INACTIVITY,
 };
 
 static const unsigned int adxl313_act_int_reg[] = {
 	[ADXL313_ACTIVITY] = ADXL313_INT_ACTIVITY,
+	[ADXL313_INACTIVITY] = ADXL313_INT_INACTIVITY,
 };
 
 static const unsigned int adxl313_act_thresh_reg[] = {
 	[ADXL313_ACTIVITY] = ADXL313_REG_THRESH_ACT,
+	[ADXL313_INACTIVITY] = ADXL313_REG_THRESH_INACT,
 };
 
 static const struct regmap_range adxl312_readable_reg_range[] = {
@@ -253,6 +257,17 @@ static const struct iio_event_spec adxl313_activity_events[] = {
 	},
 };
 
+static const struct iio_event_spec adxl313_inactivity_events[] = {
+	{
+		/* inactivity */
+		.type = IIO_EV_TYPE_MAG,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
+			BIT(IIO_EV_INFO_PERIOD),
+	},
+};
+
 enum adxl313_chans {
 	chan_x, chan_y, chan_z,
 };
@@ -269,6 +284,14 @@ static const struct iio_chan_spec adxl313_channels[] = {
 		.event_spec = adxl313_activity_events,
 		.num_event_specs = ARRAY_SIZE(adxl313_activity_events),
 	},
+	{
+		.type = IIO_ACCEL,
+		.modified = 1,
+		.channel2 = IIO_MOD_X_AND_Y_AND_Z,
+		.scan_index = -1, /* Fake channel for axis AND'ing */
+		.event_spec = adxl313_inactivity_events,
+		.num_event_specs = ARRAY_SIZE(adxl313_inactivity_events),
+	},
 };
 
 static const unsigned long adxl313_scan_masks[] = {
@@ -331,6 +354,15 @@ static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
 	}
 }
 
+static int adxl313_set_inact_time_s(struct adxl313_data *data,
+				    unsigned int val_s)
+{
+	unsigned int max_boundary = U8_MAX; /* by register size */
+	unsigned int val = min(val_s, max_boundary);
+
+	return regmap_write(data->regmap, ADXL313_REG_TIME_INACT, val);
+}
+
 static int adxl313_is_act_inact_en(struct adxl313_data *data,
 				   enum adxl313_activity_type type)
 {
@@ -348,6 +380,10 @@ static int adxl313_is_act_inact_en(struct adxl313_data *data,
 		if (!FIELD_GET(ADXL313_ACT_XYZ_EN, axis_ctrl))
 			return false;
 		break;
+	case ADXL313_INACTIVITY:
+		if (!FIELD_GET(ADXL313_INACT_XYZ_EN, axis_ctrl))
+			return false;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -366,6 +402,7 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 {
 	unsigned int axis_ctrl;
 	unsigned int threshold;
+	unsigned int inact_time_s;
 	int ret;
 
 	if (cmd_en) {
@@ -377,6 +414,18 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 
 		if (!threshold) /* Just ignore the command if threshold is 0 */
 			return 0;
+
+		/* When turning on inactivity, check if inact time is valid */
+		if (type == ADXL313_INACTIVITY) {
+			ret = regmap_read(data->regmap,
+					  ADXL313_REG_TIME_INACT,
+					  &inact_time_s);
+			if (ret)
+				return ret;
+
+			if (!inact_time_s)
+				return 0;
+		}
 	}
 
 	/* Start modifying configuration registers */
@@ -389,6 +438,9 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	case ADXL313_ACTIVITY:
 		axis_ctrl = ADXL313_ACT_XYZ_EN;
 		break;
+	case ADXL313_INACTIVITY:
+		axis_ctrl = ADXL313_INACT_XYZ_EN;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -481,11 +533,14 @@ static int adxl313_write_raw(struct iio_dev *indio_dev,
 
 static int adxl313_read_mag_config(struct adxl313_data *data,
 				   enum iio_event_direction dir,
-				   enum adxl313_activity_type type_act)
+				   enum adxl313_activity_type type_act,
+				   enum adxl313_activity_type type_inact)
 {
 	switch (dir) {
 	case IIO_EV_DIR_RISING:
 		return !!adxl313_is_act_inact_en(data, type_act);
+	case IIO_EV_DIR_FALLING:
+		return !!adxl313_is_act_inact_en(data, type_inact);
 	default:
 		return -EINVAL;
 	}
@@ -494,11 +549,14 @@ static int adxl313_read_mag_config(struct adxl313_data *data,
 static int adxl313_write_mag_config(struct adxl313_data *data,
 				    enum iio_event_direction dir,
 				    enum adxl313_activity_type type_act,
+				    enum adxl313_activity_type type_inact,
 				    bool state)
 {
 	switch (dir) {
 	case IIO_EV_DIR_RISING:
 		return adxl313_set_act_inact_en(data, type_act, state);
+	case IIO_EV_DIR_FALLING:
+		return adxl313_set_act_inact_en(data, type_inact, state);
 	default:
 		return -EINVAL;
 	}
@@ -514,7 +572,8 @@ static int adxl313_read_event_config(struct iio_dev *indio_dev,
 	switch (type) {
 	case IIO_EV_TYPE_MAG:
 		return adxl313_read_mag_config(data, dir,
-					       ADXL313_ACTIVITY);
+					       ADXL313_ACTIVITY,
+					       ADXL313_INACTIVITY);
 	default:
 		return -EINVAL;
 	}
@@ -532,6 +591,7 @@ static int adxl313_write_event_config(struct iio_dev *indio_dev,
 	case IIO_EV_TYPE_MAG:
 		return adxl313_write_mag_config(data, dir,
 						ADXL313_ACTIVITY,
+						ADXL313_INACTIVITY,
 						state);
 	default:
 		return -EINVAL;
@@ -542,9 +602,11 @@ static int adxl313_read_mag_value(struct adxl313_data *data,
 				  enum iio_event_direction dir,
 				  enum iio_event_info info,
 				  enum adxl313_activity_type type_act,
+				  enum adxl313_activity_type type_inact,
 				  int *val, int *val2)
 {
 	unsigned int threshold;
+	unsigned int period;
 	int ret;
 
 	switch (info) {
@@ -559,9 +621,25 @@ static int adxl313_read_mag_value(struct adxl313_data *data,
 			*val = threshold * 15625;
 			*val2 = MICRO;
 			return IIO_VAL_FRACTIONAL;
+		case IIO_EV_DIR_FALLING:
+			ret = regmap_read(data->regmap,
+					  adxl313_act_thresh_reg[type_inact],
+					  &threshold);
+			if (ret)
+				return ret;
+			*val = threshold * 15625;
+			*val2 = MICRO;
+			return IIO_VAL_FRACTIONAL;
 		default:
 			return -EINVAL;
 		}
+	case IIO_EV_INFO_PERIOD:
+		ret = regmap_read(data->regmap, ADXL313_REG_TIME_INACT,
+				  &period);
+		if (ret)
+			return ret;
+		*val = period;
+		return IIO_VAL_INT;
 	default:
 		return -EINVAL;
 	}
@@ -571,6 +649,7 @@ static int adxl313_write_mag_value(struct adxl313_data *data,
 				   enum iio_event_direction dir,
 				   enum iio_event_info info,
 				   enum adxl313_activity_type type_act,
+				   enum adxl313_activity_type type_inact,
 				   int val, int val2)
 {
 	unsigned int regval;
@@ -584,9 +663,15 @@ static int adxl313_write_mag_value(struct adxl313_data *data,
 			return regmap_write(data->regmap,
 					    adxl313_act_thresh_reg[type_act],
 					    regval);
+		case IIO_EV_DIR_FALLING:
+			return regmap_write(data->regmap,
+					    adxl313_act_thresh_reg[type_inact],
+					    regval);
 		default:
 			return -EINVAL;
 		}
+	case IIO_EV_INFO_PERIOD:
+		return adxl313_set_inact_time_s(data, val);
 	default:
 		return -EINVAL;
 	}
@@ -605,6 +690,7 @@ static int adxl313_read_event_value(struct iio_dev *indio_dev,
 	case IIO_EV_TYPE_MAG:
 		return adxl313_read_mag_value(data, dir, info,
 					      ADXL313_ACTIVITY,
+					      ADXL313_INACTIVITY,
 					      val, val2);
 	default:
 		return -EINVAL;
@@ -624,6 +710,7 @@ static int adxl313_write_event_value(struct iio_dev *indio_dev,
 	case IIO_EV_TYPE_MAG:
 		return adxl313_write_mag_value(data, dir, info,
 					       ADXL313_ACTIVITY,
+					       ADXL313_INACTIVITY,
 					       val, val2);
 	default:
 		return -EINVAL;
@@ -784,6 +871,17 @@ static int adxl313_push_events(struct iio_dev *indio_dev, int int_stat)
 			return ret;
 	}
 
+	if (FIELD_GET(ADXL313_INT_INACTIVITY, int_stat)) {
+		ret = iio_push_event(indio_dev,
+				     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+							IIO_MOD_X_AND_Y_AND_Z,
+							IIO_EV_TYPE_MAG,
+							IIO_EV_DIR_FALLING),
+				     ts);
+		if (ret)
+			return ret;
+	}
+
 	return ret;
 }
 
@@ -989,6 +1087,14 @@ int adxl313_core_probe(struct device *dev,
 		if (ret)
 			return ret;
 
+		ret = regmap_write(data->regmap, ADXL313_REG_TIME_INACT, 5);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(data->regmap, ADXL313_REG_THRESH_INACT, 0x4f);
+		if (ret)
+			return ret;
+
 		ret = regmap_write(data->regmap, ADXL313_REG_THRESH_ACT, 0x52);
 		if (ret)
 			return ret;
-- 
2.39.5

[PATCH v7 6/8] iio: accel: adxl313: implement power-save on inactivity

[Lothar Rubusch]

Configure the link bit to associate activity and inactivity sensing,
allowing the sensor to reflect its internal power-saving state.
Additionally, enable the auto-sleep bit to transition the sensor into
auto-sleep mode during periods of inactivity, as outlined in the
datasheet.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |  3 +++
 drivers/iio/accel/adxl313_core.c | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index d7e8cb44855b..75ef54b60f75 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -41,6 +41,9 @@
 #define ADXL313_RATE_BASE		6
 
 #define ADXL313_POWER_CTL_MSK		BIT(3)
+#define ADXL313_POWER_CTL_INACT_MSK	GENMASK(5, 4)
+#define ADXL313_POWER_CTL_LINK		BIT(5)
+#define ADXL313_POWER_CTL_AUTO_SLEEP	BIT(4)
 
 #define ADXL313_RANGE_MSK		GENMASK(1, 0)
 #define ADXL313_RANGE_MAX		3
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index e904dee4dc2b..df10dc430e1c 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -396,6 +396,23 @@ static int adxl313_is_act_inact_en(struct adxl313_data *data,
 	return adxl313_act_int_reg[type] & regval;
 }
 
+static int adxl313_set_act_inact_linkbit(struct adxl313_data *data, bool en)
+{
+	int act_en, inact_en;
+
+	act_en = adxl313_is_act_inact_en(data, ADXL313_ACTIVITY);
+	if (act_en < 0)
+		return act_en;
+
+	inact_en = adxl313_is_act_inact_en(data, ADXL313_INACTIVITY);
+	if (inact_en < 0)
+		return inact_en;
+
+	return regmap_assign_bits(data->regmap, ADXL313_REG_POWER_CTL,
+				  ADXL313_POWER_CTL_AUTO_SLEEP | ADXL313_POWER_CTL_LINK,
+				  en && act_en && inact_en);
+}
+
 static int adxl313_set_act_inact_en(struct adxl313_data *data,
 				    enum adxl313_activity_type type,
 				    bool cmd_en)
@@ -455,6 +472,11 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	if (ret)
 		return ret;
 
+	/* Set link-bit and auto-sleep only when ACT and INACT are enabled */
+	ret = adxl313_set_act_inact_linkbit(data, cmd_en);
+	if (ret)
+		return ret;
+
 	return adxl313_set_measure_en(data, true);
 }
 
-- 
2.39.5

[PATCH v7 7/8] iio: accel: adxl313: add AC coupled activity/inactivity events

[Lothar Rubusch]

Introduce AC-coupled activity and inactivity as MAG_ADAPTIVE events.
This adds a new set of threshold and duration configuration options,
ensures proper handling of event disabling, and extends the use of the
link bit to support complementary event configurations.

For example, either ACTIVITY or ACTIVITY_AC can be enabled, but only the
most recently set configuration will remain active. Disabling ACTIVITY
will have no effect if ACTIVITY_AC is currently enabled, as the event
types must match (i.e., ACTIVITY_AC must be explicitly disabled). When
either INACTIVITY or INACTIVITY_AC is enabled alongside an activity
event, the link bit is set.

With the link bit and auto-sleep enabled, activity and inactivity events
represent changes in the sensor's power-saving state and are only
triggered upon actual state transitions. Since AC coupling uses separate
bits for activity and inactivity, each can be configured independently.
For instance, ACTIVITY can be linked with INACTIVITY_AC.

If one of the linked events is disabled, the link bit is cleared. In
that case, the remaining event will no longer reflect a state transition
but will instead trigger based on periodic inactivity or whenever the
activity threshold is exceeded.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313_core.c | 214 +++++++++++++++++++++++++++++--
 1 file changed, 200 insertions(+), 14 deletions(-)

diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index df10dc430e1c..c62e669d41e8 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -30,20 +30,38 @@
 #define ADXL313_ACT_XYZ_EN			GENMASK(6, 4)
 #define ADXL313_INACT_XYZ_EN			GENMASK(2, 0)
 
+#define ADXL313_REG_ACT_ACDC_MSK		BIT(7)
+#define ADXL313_REG_INACT_ACDC_MSK		BIT(3)
+#define ADXL313_COUPLING_DC			0
+#define ADXL313_COUPLING_AC			1
+
 /* activity/inactivity */
 enum adxl313_activity_type {
 	ADXL313_ACTIVITY,
 	ADXL313_INACTIVITY,
+	ADXL313_ACTIVITY_AC,
+	ADXL313_INACTIVITY_AC,
 };
 
 static const unsigned int adxl313_act_int_reg[] = {
 	[ADXL313_ACTIVITY] = ADXL313_INT_ACTIVITY,
 	[ADXL313_INACTIVITY] = ADXL313_INT_INACTIVITY,
+	[ADXL313_ACTIVITY_AC] = ADXL313_INT_ACTIVITY,
+	[ADXL313_INACTIVITY_AC] = ADXL313_INT_INACTIVITY,
 };
 
 static const unsigned int adxl313_act_thresh_reg[] = {
 	[ADXL313_ACTIVITY] = ADXL313_REG_THRESH_ACT,
 	[ADXL313_INACTIVITY] = ADXL313_REG_THRESH_INACT,
+	[ADXL313_ACTIVITY_AC] = ADXL313_REG_THRESH_ACT,
+	[ADXL313_INACTIVITY_AC] = ADXL313_REG_THRESH_INACT,
+};
+
+static const unsigned int adxl313_act_acdc_msk[] = {
+	[ADXL313_ACTIVITY] = ADXL313_REG_ACT_ACDC_MSK,
+	[ADXL313_INACTIVITY] = ADXL313_REG_INACT_ACDC_MSK,
+	[ADXL313_ACTIVITY_AC] = ADXL313_REG_ACT_ACDC_MSK,
+	[ADXL313_INACTIVITY_AC] = ADXL313_REG_INACT_ACDC_MSK,
 };
 
 static const struct regmap_range adxl312_readable_reg_range[] = {
@@ -255,6 +273,13 @@ static const struct iio_event_spec adxl313_activity_events[] = {
 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
 	},
+	{
+		/* activity, AC bit set */
+		.type = IIO_EV_TYPE_MAG_ADAPTIVE,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
+	},
 };
 
 static const struct iio_event_spec adxl313_inactivity_events[] = {
@@ -266,6 +291,14 @@ static const struct iio_event_spec adxl313_inactivity_events[] = {
 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_PERIOD),
 	},
+	{
+		/* inactivity, AC bit set */
+		.type = IIO_EV_TYPE_MAG_ADAPTIVE,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
+			BIT(IIO_EV_INFO_PERIOD),
+	},
 };
 
 enum adxl313_chans {
@@ -363,11 +396,72 @@ static int adxl313_set_inact_time_s(struct adxl313_data *data,
 	return regmap_write(data->regmap, ADXL313_REG_TIME_INACT, val);
 }
 
+/**
+ * adxl313_is_act_inact_ac() - Check if AC coupling is enabled.
+ * @data: The device data.
+ * @type: The activity or inactivity type.
+ *
+ * Provide a type of activity or inactivity, combined with either AC coupling
+ * set, or default to DC coupling. This function verifies if the combination is
+ * currently enabled or not.
+ *
+ * Return: if the provided activity type has AC coupling enabled or a negative
+ * error value.
+ */
+static int adxl313_is_act_inact_ac(struct adxl313_data *data,
+				   enum adxl313_activity_type type)
+{
+	unsigned int regval;
+	bool coupling;
+	int ret;
+
+	ret = regmap_read(data->regmap, ADXL313_REG_ACT_INACT_CTL, &regval);
+	if (ret)
+		return ret;
+
+	coupling = adxl313_act_acdc_msk[type] & regval;
+
+	switch (type) {
+	case ADXL313_ACTIVITY:
+	case ADXL313_INACTIVITY:
+		return coupling == ADXL313_COUPLING_DC;
+	case ADXL313_ACTIVITY_AC:
+	case ADXL313_INACTIVITY_AC:
+		return coupling == ADXL313_COUPLING_AC;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxl313_set_act_inact_ac(struct adxl313_data *data,
+				    enum adxl313_activity_type type,
+				    bool cmd_en)
+{
+	unsigned int act_inact_ac;
+
+	switch (type) {
+	case ADXL313_ACTIVITY_AC:
+	case ADXL313_INACTIVITY_AC:
+		act_inact_ac = ADXL313_COUPLING_AC && cmd_en;
+		break;
+	case ADXL313_ACTIVITY:
+	case ADXL313_INACTIVITY:
+		act_inact_ac = ADXL313_COUPLING_DC && cmd_en;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_assign_bits(data->regmap, ADXL313_REG_ACT_INACT_CTL,
+				  adxl313_act_acdc_msk[type], act_inact_ac);
+}
+
 static int adxl313_is_act_inact_en(struct adxl313_data *data,
 				   enum adxl313_activity_type type)
 {
 	unsigned int axis_ctrl;
 	unsigned int regval;
+	bool int_en;
 	int ret;
 
 	ret = regmap_read(data->regmap, ADXL313_REG_ACT_INACT_CTL, &axis_ctrl);
@@ -377,10 +471,12 @@ static int adxl313_is_act_inact_en(struct adxl313_data *data,
 	/* Check if axis for activity are enabled */
 	switch (type) {
 	case ADXL313_ACTIVITY:
+	case ADXL313_ACTIVITY_AC:
 		if (!FIELD_GET(ADXL313_ACT_XYZ_EN, axis_ctrl))
 			return false;
 		break;
 	case ADXL313_INACTIVITY:
+	case ADXL313_INACTIVITY_AC:
 		if (!FIELD_GET(ADXL313_INACT_XYZ_EN, axis_ctrl))
 			return false;
 		break;
@@ -393,21 +489,39 @@ static int adxl313_is_act_inact_en(struct adxl313_data *data,
 	if (ret)
 		return ret;
 
-	return adxl313_act_int_reg[type] & regval;
+	int_en = adxl313_act_int_reg[type] & regval;
+	if (!int_en)
+		return false;
+
+	/* Check if configured coupling matches provided type */
+	return adxl313_is_act_inact_ac(data, type);
 }
 
 static int adxl313_set_act_inact_linkbit(struct adxl313_data *data, bool en)
 {
+	int act_ac_en, inact_ac_en;
 	int act_en, inact_en;
 
 	act_en = adxl313_is_act_inact_en(data, ADXL313_ACTIVITY);
 	if (act_en < 0)
 		return act_en;
 
+	act_ac_en = adxl313_is_act_inact_en(data, ADXL313_ACTIVITY_AC);
+	if (act_ac_en < 0)
+		return act_ac_en;
+
 	inact_en = adxl313_is_act_inact_en(data, ADXL313_INACTIVITY);
 	if (inact_en < 0)
 		return inact_en;
 
+	inact_ac_en = adxl313_is_act_inact_en(data, ADXL313_INACTIVITY_AC);
+	if (inact_ac_en < 0)
+		return inact_ac_en;
+
+	act_en = act_en || act_ac_en;
+
+	inact_en = inact_en || inact_ac_en;
+
 	return regmap_assign_bits(data->regmap, ADXL313_REG_POWER_CTL,
 				  ADXL313_POWER_CTL_AUTO_SLEEP | ADXL313_POWER_CTL_LINK,
 				  en && act_en && inact_en);
@@ -433,7 +547,7 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 			return 0;
 
 		/* When turning on inactivity, check if inact time is valid */
-		if (type == ADXL313_INACTIVITY) {
+		if (type == ADXL313_INACTIVITY || type == ADXL313_INACTIVITY_AC) {
 			ret = regmap_read(data->regmap,
 					  ADXL313_REG_TIME_INACT,
 					  &inact_time_s);
@@ -443,6 +557,16 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 			if (!inact_time_s)
 				return 0;
 		}
+	} else {
+		/*
+		 * When turning off an activity, ensure that the correct
+		 * coupling event is specified. This step helps prevent misuse -
+		 * for example, if an AC-coupled activity is active and the
+		 * current call attempts to turn off a DC-coupled activity, this
+		 * inconsistency should be detected here.
+		 */
+		if (adxl313_is_act_inact_ac(data, type) <= 0)
+			return 0;
 	}
 
 	/* Start modifying configuration registers */
@@ -453,9 +577,11 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	/* Enable axis according to the command */
 	switch (type) {
 	case ADXL313_ACTIVITY:
+	case ADXL313_ACTIVITY_AC:
 		axis_ctrl = ADXL313_ACT_XYZ_EN;
 		break;
 	case ADXL313_INACTIVITY:
+	case ADXL313_INACTIVITY_AC:
 		axis_ctrl = ADXL313_INACT_XYZ_EN;
 		break;
 	default:
@@ -466,6 +592,11 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	if (ret)
 		return ret;
 
+	/* Update AC/DC-coupling according to the command */
+	ret = adxl313_set_act_inact_ac(data, type, cmd_en);
+	if (ret)
+		return ret;
+
 	/* Enable the interrupt line, according to the command */
 	ret = regmap_assign_bits(data->regmap, ADXL313_REG_INT_ENABLE,
 				 adxl313_act_int_reg[type], cmd_en);
@@ -596,6 +727,10 @@ static int adxl313_read_event_config(struct iio_dev *indio_dev,
 		return adxl313_read_mag_config(data, dir,
 					       ADXL313_ACTIVITY,
 					       ADXL313_INACTIVITY);
+	case IIO_EV_TYPE_MAG_ADAPTIVE:
+		return adxl313_read_mag_config(data, dir,
+					       ADXL313_ACTIVITY_AC,
+					       ADXL313_INACTIVITY_AC);
 	default:
 		return -EINVAL;
 	}
@@ -615,6 +750,11 @@ static int adxl313_write_event_config(struct iio_dev *indio_dev,
 						ADXL313_ACTIVITY,
 						ADXL313_INACTIVITY,
 						state);
+	case IIO_EV_TYPE_MAG_ADAPTIVE:
+		return adxl313_write_mag_config(data, dir,
+						ADXL313_ACTIVITY_AC,
+						ADXL313_INACTIVITY_AC,
+						state);
 	default:
 		return -EINVAL;
 	}
@@ -714,6 +854,11 @@ static int adxl313_read_event_value(struct iio_dev *indio_dev,
 					      ADXL313_ACTIVITY,
 					      ADXL313_INACTIVITY,
 					      val, val2);
+	case IIO_EV_TYPE_MAG_ADAPTIVE:
+		return adxl313_read_mag_value(data, dir, info,
+					      ADXL313_ACTIVITY_AC,
+					      ADXL313_INACTIVITY_AC,
+					      val, val2);
 	default:
 		return -EINVAL;
 	}
@@ -734,6 +879,11 @@ static int adxl313_write_event_value(struct iio_dev *indio_dev,
 					       ADXL313_ACTIVITY,
 					       ADXL313_INACTIVITY,
 					       val, val2);
+	case IIO_EV_TYPE_MAG_ADAPTIVE:
+		return adxl313_write_mag_value(data, dir, info,
+					       ADXL313_ACTIVITY_AC,
+					       ADXL313_INACTIVITY_AC,
+					       val, val2);
 	default:
 		return -EINVAL;
 	}
@@ -880,28 +1030,64 @@ static int adxl313_fifo_push(struct iio_dev *indio_dev, int samples)
 static int adxl313_push_events(struct iio_dev *indio_dev, int int_stat)
 {
 	s64 ts = iio_get_time_ns(indio_dev);
+	struct adxl313_data *data = iio_priv(indio_dev);
+	unsigned int regval;
 	int ret = -ENOENT;
 
 	if (FIELD_GET(ADXL313_INT_ACTIVITY, int_stat)) {
-		ret = iio_push_event(indio_dev,
-				     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
-							IIO_MOD_X_OR_Y_OR_Z,
-							IIO_EV_TYPE_MAG,
-							IIO_EV_DIR_RISING),
-				     ts);
+		ret = regmap_read(data->regmap, ADXL313_REG_ACT_INACT_CTL, &regval);
 		if (ret)
 			return ret;
+
+		if (FIELD_GET(ADXL313_REG_ACT_ACDC_MSK, regval)) {
+			/* AC coupled */
+			ret = iio_push_event(indio_dev,
+					     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+								IIO_MOD_X_OR_Y_OR_Z,
+								IIO_EV_TYPE_MAG_ADAPTIVE,
+								IIO_EV_DIR_RISING),
+					     ts);
+			if (ret)
+				return ret;
+		} else {
+			/* DC coupled, relying on THRESH */
+			ret = iio_push_event(indio_dev,
+					     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+								IIO_MOD_X_OR_Y_OR_Z,
+								IIO_EV_TYPE_MAG,
+								IIO_EV_DIR_RISING),
+					     ts);
+			if (ret)
+				return ret;
+		}
 	}
 
 	if (FIELD_GET(ADXL313_INT_INACTIVITY, int_stat)) {
-		ret = iio_push_event(indio_dev,
-				     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
-							IIO_MOD_X_AND_Y_AND_Z,
-							IIO_EV_TYPE_MAG,
-							IIO_EV_DIR_FALLING),
-				     ts);
+		ret = regmap_read(data->regmap, ADXL313_REG_ACT_INACT_CTL, &regval);
 		if (ret)
 			return ret;
+
+		if (FIELD_GET(ADXL313_REG_INACT_ACDC_MSK, regval)) {
+			/* AC coupled */
+			ret = iio_push_event(indio_dev,
+					     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+								IIO_MOD_X_AND_Y_AND_Z,
+								IIO_EV_TYPE_MAG_ADAPTIVE,
+								IIO_EV_DIR_FALLING),
+					     ts);
+			if (ret)
+				return ret;
+		} else {
+			/* DC coupled, relying on THRESH */
+			ret = iio_push_event(indio_dev,
+					     IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
+								IIO_MOD_X_AND_Y_AND_Z,
+								IIO_EV_TYPE_MAG,
+								IIO_EV_DIR_FALLING),
+					     ts);
+			if (ret)
+				return ret;
+		}
 	}
 
 	return ret;
-- 
2.39.5

[PATCH v7 8/8] docs: iio: add ADXL313 accelerometer

[Lothar Rubusch]

Add documentation for the ADXL313 accelerometer driver.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 Documentation/iio/adxl313.rst | 289 ++++++++++++++++++++++++++++++++++
 Documentation/iio/index.rst   |   1 +
 2 files changed, 290 insertions(+)
 create mode 100644 Documentation/iio/adxl313.rst

diff --git a/Documentation/iio/adxl313.rst b/Documentation/iio/adxl313.rst
new file mode 100644
index 000000000000..41b9cc37981c
--- /dev/null
+++ b/Documentation/iio/adxl313.rst
@@ -0,0 +1,289 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===============
+ADXL313 driver
+===============
+
+This driver supports Analog Device's ADXL313 on SPI/I2C bus.
+
+1. Supported devices
+====================
+
+* `ADXL313 <https://www.analog.com/ADXL313>`_
+
+The ADXL313is a low noise density, low power, 3-axis accelerometer with
+selectable measurement ranges. The ADXL313 supports the ±0.5 g, ±1 g, ±2 g and
+±4 g ranges.
+
+2. Device attributes
+====================
+
+Accelerometer measurements are always provided.
+
+Each IIO device, has a device folder under ``/sys/bus/iio/devices/iio:deviceX``,
+where X is the IIO index of the device. Under these folders reside a set of
+device files, depending on the characteristics and features of the hardware
+device in questions. These files are consistently generalized and documented in
+the IIO ABI documentation.
+
+The following tables show the adxl313 related device files, found in the
+specific device folder path ``/sys/bus/iio/devices/iio:deviceX``.
+
++---------------------------------------------------+----------------------------------------------------------+
+| 3-Axis Accelerometer related device files         | Description                                              |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_scale                                    | Scale for the accelerometer channels.                    |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x_calibbias                              | Calibration offset for the X-axis accelerometer channel. |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x_raw                                    | Raw X-axis accelerometer channel value.                  |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_y_calibbias                              | y-axis acceleration offset correction                    |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_y_raw                                    | Raw Y-axis accelerometer channel value.                  |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_z_calibbias                              | Calibration offset for the Z-axis accelerometer channel. |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_z_raw                                    | Raw Z-axis accelerometer channel value.                  |
++---------------------------------------------------+----------------------------------------------------------+
+
++---------------------------------------+----------------------------------------------+
+| Miscellaneous device files            | Description                                  |
++---------------------------------------+----------------------------------------------+
+| name                                  | Name of the IIO device.                      |
++---------------------------------------+----------------------------------------------+
+| in_accel_sampling_frequency           | Currently selected sample rate.              |
++---------------------------------------+----------------------------------------------+
+| in_accel_sampling_frequency_available | Available sampling frequency configurations. |
++---------------------------------------+----------------------------------------------+
+
+The iio event related settings, found in ``/sys/bus/iio/devices/iio:deviceX/events``.
+
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_adaptive_falling_period              | AC coupled inactivity time.                              |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_adaptive_falling_value               | AC coupled inactivity threshold.                         |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_adaptive_rising_value                | AC coupled activity threshold.                           |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_falling_period                       | Inactivity time.                                         |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_falling_value                        | Inactivity threshold.                                    |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_mag_rising_value                         | Activity threshold.                                      |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x\&y\&z_mag_adaptive_falling_en          | Enable or disable AC coupled inactivity events.          |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x\|y\|z_mag_adaptive_rising_en           | Enable or disable AC coupled activity events.            |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x\&y\&z_mag_falling_en                   | Enable or disable inactivity events.                     |
++---------------------------------------------------+----------------------------------------------------------+
+| in_accel_x\|y\|z_mag_rising_en                    | Enable or disable activity events.                       |
++---------------------------------------------------+----------------------------------------------------------+
+
+The default coupling is DC coupled events. In this case the threshold will
+be in place as such, where for the AC coupled case an adaptive threshold
+(described in the datasheet) will be applied by the sensor. In general activity,
+i.e. ``ACTIVITY`` or ``ACTIVITY_AC`` and inactivity i.e. ``INACTIVITY`` or
+``INACTIVITY_AC``, will be linked with auto-sleep enabled when both are enabled.
+This means in particular ``ACTIVITY`` can also be linked to ``INACTIVITY_AC``
+and vice versa, without problem.
+
+Note here, that ``ACTIVITY`` and ``ACTIVITY_AC`` are mutually exclusive. This
+means, that the most recent configuration will be set. For instance, if
+``ACTIVITY`` is enabled, and ``ACTIVITY_AC`` will be enabled, the sensor driver
+will have ``ACTIVITY`` disabled, but ``ACTIVITY_AC`` enabled. The same is valid
+for inactivity. In case of turning off an event, it has to match to what is
+actually enabled, i.e. enabling ``ACTIVITY_AC`` and then disabling ``ACTIVITY``
+is simply ignored as it is already disabled. Or, as if it was any other not
+enabled event, too.
+
+Channels processed values
+-------------------------
+
+A channel value can be read from its _raw attribute. The value returned is the
+raw value as reported by the devices. To get the processed value of the channel,
+apply the following formula:
+
+.. code-block::
+
+        processed value = (_raw + _offset) * _scale
+
+Where _offset and _scale are device attributes. If no _offset attribute is
+present, simply assume its value is 0.
+
+The ADXL313 driver offers data for a single types of channels, the table below
+shows the measurement units for the processed value, which are defined by the
+IIO framework:
+
++-------------------------------------+---------------------------+
+| Channel type                        | Measurement unit          |
++-------------------------------------+---------------------------+
+| Acceleration on X, Y, and Z axis    | Meters per Second squared |
++-------------------------------------+---------------------------+
+
+Usage examples
+--------------
+
+Show device name:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> cat name
+        adxl313
+
+Show accelerometer channels value:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_raw
+        2
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_y_raw
+        -57
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_z_raw
+        2
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_scale
+        0.009576806
+
+The accelerometer values will be:
+
+- X-axis acceleration = in_accel_x_raw * in_accel_scale = 0.0191536 m/s^2
+- Y-axis acceleration = in_accel_y_raw * in_accel_scale = -0.5458779 m/s^2
+- Z-axis acceleration = in_accel_z_raw * in_accel_scale = 0.0191536 m/s^2
+
+Set calibration offset for accelerometer channels. Note, that the calibration
+will be rounded according to the graduation of LSB units:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
+        0
+
+        root:/sys/bus/iio/devices/iio:device0> echo 50 > in_accel_x_calibbias
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
+        48
+
+Set sampling frequency:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_sampling_frequency
+        100.000000
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_sampling_frequency_available
+        6.250000 12.500000 25.000000 50.000000 100.000000 200.000000 400.000000 800.000000 1600.000000 3200.000000
+
+        root:/sys/bus/iio/devices/iio:device0> echo 400 > in_accel_sampling_frequency
+        root:/sys/bus/iio/devices/iio:device0> cat in_accel_sampling_frequency
+        400.000000
+
+3. Device buffers and triggers
+==============================
+
+This driver supports IIO buffers.
+
+All devices support retrieving the raw acceleration measurements using buffers.
+
+Usage examples
+--------------
+
+Select channels for buffer read:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_x_en
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_y_en
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_z_en
+
+Set the number of samples to be stored in the buffer:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> echo 10 > buffer/length
+
+Enable buffer readings:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > buffer/enable
+
+Obtain buffered data:
+
+.. code-block:: bash
+
+        root:/sys/bus/iio/devices/iio:device0> hexdump -C /dev/iio\:device0
+        ...
+        000000d0  01 fc 31 00 c7 ff 03 fc  31 00 c7 ff 04 fc 33 00  |..1.....1.....3.|
+        000000e0  c8 ff 03 fc 32 00 c5 ff  ff fc 32 00 c7 ff 0a fc  |....2.....2.....|
+        000000f0  30 00 c8 ff 06 fc 33 00  c7 ff 01 fc 2f 00 c8 ff  |0.....3...../...|
+        00000100  02 fc 32 00 c6 ff 04 fc  33 00 c8 ff 05 fc 33 00  |..2.....3.....3.|
+        00000110  ca ff 02 fc 31 00 c7 ff  02 fc 30 00 c9 ff 09 fc  |....1.....0.....|
+        00000120  35 00 c9 ff 08 fc 35 00  c8 ff 02 fc 31 00 c5 ff  |5.....5.....1...|
+        00000130  03 fc 32 00 c7 ff 04 fc  32 00 c7 ff 02 fc 31 00  |..2.....2.....1.|
+        00000140  c7 ff 08 fc 30 00 c7 ff  02 fc 32 00 c5 ff ff fc  |....0.....2.....|
+        00000150  31 00 c5 ff 04 fc 31 00  c8 ff 03 fc 32 00 c8 ff  |1.....1.....2...|
+        00000160  01 fc 31 00 c7 ff 05 fc  31 00 c3 ff 04 fc 31 00  |..1.....1.....1.|
+        00000170  c5 ff 04 fc 30 00 c7 ff  03 fc 31 00 c9 ff 03 fc  |....0.....1.....|
+        ...
+
+Enabling activity detection:
+
+.. code-block:: bash
+        root:/sys/bus/iio/devices/iio:device0> echo 1.28125 > ./events/in_accel_mag_rising_value
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > ./events/in_accel_x\|y\|z_mag_rising_en
+
+        root:/sys/bus/iio/devices/iio:device0> iio_event_monitor adxl313
+        Found IIO device with name adxl313 with device number 0
+        <only while moving the sensor>
+        Event: time: 1748795762298351281, type: accel(x|y|z), channel: 0, evtype: mag, direction: rising
+        Event: time: 1748795762302653704, type: accel(x|y|z), channel: 0, evtype: mag, direction: rising
+        Event: time: 1748795762304340726, type: accel(x|y|z), channel: 0, evtype: mag, direction: rising
+        ...
+
+Disabling activity detection:
+
+.. code-block:: bash
+        root:/sys/bus/iio/devices/iio:device0> echo 0 > ./events/in_accel_x\|y\|z_mag_rising_en
+        root:/sys/bus/iio/devices/iio:device0> iio_event_monitor adxl313
+        <nothing>
+
+Enabling inactivity detection:
+
+.. code-block:: bash
+        root:/sys/bus/iio/devices/iio:device0> echo 1.234375 > ./events/in_accel_mag_falling_value
+        root:/sys/bus/iio/devices/iio:device0> echo 5 > ./events/in_accel_mag_falling_period
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > ./events/in_accel_x\&y\&z_mag_falling_en
+
+        root:/sys/bus/iio/devices/iio:device0> iio_event_monitor adxl313
+        Found IIO device with name adxl313 with device number 0
+        Event: time: 1748796324115962975, type: accel(x&y&z), channel: 0, evtype: mag, direction: falling
+        Event: time: 1748796329329981772, type: accel(x&y&z), channel: 0, evtype: mag, direction: falling
+        Event: time: 1748796334543399706, type: accel(x&y&z), channel: 0, evtype: mag, direction: falling
+        ...
+        <every 5s now indicates inactivity>
+
+Now, enabling activity, e.g. the AC coupled counter-part ``ACTIVITY_AC``
+
+.. code-block:: bash
+        root:/sys/bus/iio/devices/iio:device0> echo 1.28125 > ./events/in_accel_mag_rising_value
+        root:/sys/bus/iio/devices/iio:device0> echo 1 > ./events/in_accel_x\|y\|z_mag_rising_en
+
+        root:/sys/bus/iio/devices/iio:device0> iio_event_monitor adxl313
+        Found IIO device with name adxl313 with device number 0
+        <some activity with the sensor>
+        Event: time: 1748796880354686777, type: accel(x|y|z), channel: 0, evtype: mag_adaptive, direction: rising
+        <5s of inactivity, then>
+        Event: time: 1748796885543252017, type: accel(x&y&z), channel: 0, evtype: mag, direction: falling
+        <some other activity detected by accelerating the sensor>
+        Event: time: 1748796887756634678, type: accel(x|y|z), channel: 0, evtype: mag_adaptive, direction: rising
+        <again, 5s of inactivity>
+        Event: time: 1748796892964368352, type: accel(x&y&z), channel: 0, evtype: mag, direction: falling
+        <stays like this until next activity in auto-sleep>
+
+Note, when AC coupling is in place, the event type will be of ``mag_adaptive``.
+AC- or DC-coupled (the default) events are used similarly.
+
+4. IIO Interfacing Tools
+========================
+
+See Documentation/iio/iio_tools.rst for the description of the available IIO
+interfacing tools.
diff --git a/Documentation/iio/index.rst b/Documentation/iio/index.rst
index 2d6afc5a8ed5..c106402a91f7 100644
--- a/Documentation/iio/index.rst
+++ b/Documentation/iio/index.rst
@@ -31,6 +31,7 @@ Industrial I/O Kernel Drivers
    adis16475
    adis16480
    adis16550
+   adxl313
    adxl380
    bno055
    ep93xx_adc
-- 
2.39.5

Re: [PATCH v7 3/8] iio: accel: adxl313: add buffered FIFO watermark with interrupt handling

[Andy Shevchenko]

On Wed, Jul 02, 2025 at 11:08:14PM +0000, Lothar Rubusch wrote:
> Cover the following tasks:
> - Add scan_mask and scan_index to the IIO channel configuration. The
> scan_index sets up buffer usage. According to the datasheet, the ADXL313
> uses a 13-bit wide data field in full-resolution mode. Set the
> signedness, number of storage bits, and endianness accordingly.
> 
> - Parse the devicetree for an optional interrupt line and configure the
> interrupt mapping based on its presence. If no interrupt line is
> specified, keep the FIFO in bypass mode as currently implemented.
> 
> - Set up the interrupt handler. Add register access to detect and
> evaluate interrupts. Implement functions to clear status registers and
> reset the FIFO.
> 
> - Implement FIFO watermark configuration and handling. Allow the
> watermark level to be set, evaluate the corresponding interrupt, read
> the FIFO contents, and push the data to the IIO channel.

...

> +err:

The rule of thumb for naming error labels is an answer to "what does code do
when I goto $LABEL?". In other words name should encode what will be done when
goto. In this case I would make it

err_fifo_reset:

The rationale is that reading the code won't require to "goto" to understand
what 'err' means.

> +	adxl313_fifo_reset(data);
> +
> +	return IRQ_HANDLED;

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v7 0/8] iio: accel: adxl313: add power-save on activity/inactivity

[Andy Shevchenko]

On Wed, Jul 02, 2025 at 11:08:11PM +0000, Lothar Rubusch wrote:
> The patch set covers the following topics:
> - add debug register and regmap cache
> - prepare iio channel scan_type and scan_index
> - prepare interrupt handling
> - implement fifo with watermark
> - add activity/inactivity together with auto-sleep with link bit
> - add ac coupled activity/inactivity, integrate with auto-sleep and link bit
> - documentation
> 
> Sorry for the fuzz: when I was about to rebase for submitting I
> noticed Jonathan actually already applied parts of this. I'd recommend
> to consider v6 rather over v5.
> 
> Since activity and inactivity here are implemented covering all axis, I
> assumed x&y&z and x|y|z, respectively. Thus the driver uses a fake
> channel for activity/inactiviy. AC-coupling is similar to other Analog Device
> accelerometers, so MAG_ADAPTIVE events are chosen. Combinations are
> documented and functionality tested and verified working.

Overall LGTM, one nit-pick somewhere, otherwise feel free to add
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
to the rest of the series (which has no my tag yet).

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v7 0/8] iio: accel: adxl313: add power-save on activity/inactivity

[Jonathan Cameron]

On Thu, 3 Jul 2025 17:40:52 +0300
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> On Wed, Jul 02, 2025 at 11:08:11PM +0000, Lothar Rubusch wrote:
> > The patch set covers the following topics:
> > - add debug register and regmap cache
> > - prepare iio channel scan_type and scan_index
> > - prepare interrupt handling
> > - implement fifo with watermark
> > - add activity/inactivity together with auto-sleep with link bit
> > - add ac coupled activity/inactivity, integrate with auto-sleep and link bit
> > - documentation
> > 
> > Sorry for the fuzz: when I was about to rebase for submitting I
> > noticed Jonathan actually already applied parts of this. I'd recommend
> > to consider v6 rather over v5.
> > 
> > Since activity and inactivity here are implemented covering all axis, I
> > assumed x&y&z and x|y|z, respectively. Thus the driver uses a fake
> > channel for activity/inactiviy. AC-coupling is similar to other Analog Device
> > accelerometers, so MAG_ADAPTIVE events are chosen. Combinations are
> > documented and functionality tested and verified working.  
> 
> Overall LGTM, one nit-pick somewhere, otherwise feel free to add
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> to the rest of the series (which has no my tag yet).
> 

Tweaked as suggested to err_reset_fifo and applied with tag on whole series.

J