Merge tag 'iio-for-6.4a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into char-misc-next

Jonathan writes:

1st set of IIO new device support, features and cleanups for the 6.4 cycle.

New device support
* bosch,bmp280
  - Add support for BMP580 - includes significant refactoring and general
    driver cleanup + support for non-volatile memory for trimming and config
    parameters.
* rohm BU27034
  - New driver for this 3 channel ambient light sensor.
  - New support library for devices where both integration time and
    amplifier gain are configurable.  In these cases a scale change
    may require changing bother underlying values. This library module
    provides code to help with this.
* st,accel
  - Add support for IIS328DQ (ID only as compatible wtih LIS331DL)
* st,lsm6dsx
  - Add support for ASM330LHB automotive MEMS sensor.
* ti,ads1100, ads1000
  - New driver for these 16 bit ADCs.
* ti,tmp117
  - Add support for older tmp116 device. Includes some general driver cleanup.

Staging driver drops
* adi,ade7854
  - Driver was a very long way from compliant with IIO infrastructure and ABI.
    If anyone wants a non staging version of this driver they are better off
    starting from scratch. Hence drop it and the associated meter.h header.

Features
* adi,ad7441r
  - Add DT binding to set sink current for digital input.
* semtech,sx9324,9360
  - Support older register mapping from firmware designed for windows.

Core improvements.
* Move iio_trigger_poll() docs to next to the implementation and add a note
  on expected caller context.
* Rename iio_trigger_poll_chained() to iio_trigger_poll_nested() so
  as to use more standard / common terminology.
* Improve main ABI docs references to offset and scale for raw values by
  making them consistent and clear.

Cleanups and minor fixes:
* adi,ad5592r
  - Add GPIO names - useful for debug.
* adi,ad7441r
  - Fix current input, loop powered mode configuration setup.
* adi,adis16475
  - Fix wrong commented value for minimum advised lower rate.
* adi,admv1013
  - Use devm_clk_get_enabled() to reduce boilerplate.
* adi,ads1210
  - Fix wrong bits for writing config register (late fix and has
    been broken a long time so not rushed upstream)
* amlogic,meson-saradc
  - Improve cleanup in error handling if BL30 handshake fails.
* apex-embedded,stx104
  - Migrate to regmap and use regmap_read_poll_timeout() to neatly handle
    retries.
  - Add local mutex to close various races.
  - Use define U16_MAX rather than value for limit.
  - Improve code readability with minor reorganization.
* atmel,ad91-sama5d2
  - Drop trivial dead code.
* kionix,kx022a
  - Drop unused structure element.
* linear,ltc2983
  - Reorganize bindings doc to enable unevaluatedProperties to be set
    in one place for all child nodes.
  - Make binding for adi,custom-thermocouple accept signed values.
* maxim,max44000
  - Add OF Device matching (of_match_table was not correctly set).
* maxim,max5522
  - Missing static
* measurement-computing,cio-dac
  - Fix wrong part name in comments.
  - Migrate to regmap.
  - Improve includes by replacing bitops.h with more direct bits.h
* qcom,pm8xxx-xoadc
  - Remove a check that can never fail.
* renesas,rcar-gyroadc
  - DT binding documentation improvements.
  - Tidy up an unused warning with __maybe_unused.
* semtech,sx_common
  - Drop docs for a structure element that doesn't exist.
* semtech,sx9500
  - Drop ACPI_PTR() and of_match_ptr() protections that just complicate
    the code / block some firmware registration types that would otherwise
    work.
* sensiron,sps30
  - Comment formatting tidy up.
* st,sensors
  - Drop duplicate text in DT binding.
* st,stm32-adc
  - Add some missing static markings.
* ti,ads1100
  - Use correct return code in dev_err_probe() call.
* x-powers,axp20x_adc - precursor series to simplify addition of AXP192.
  - General code cleanup / minor refactoring for better readabilty of code.
  - Switch from boolean value to mask for adc_en2 field to avoid hard coding
    a mask that will be different in AXP192

* tag 'iio-for-6.4a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (63 commits)
  MAINTAINERS: Add ROHM BU27034
  iio: light: ROHM BU27034 Ambient Light Sensor
  dt-bindings: iio: light: Support ROHM BU27034
  MAINTAINERS: Add IIO gain-time-scale helpers
  iio: light: Add gain-time-scale helpers
  doc: Make sysfs-bus-iio doc more exact
  iio: dac: set variable max5522_channels storage-class-specifier to static
  dt-bindings: iio: temperature: ltc2983: Make 'adi,custom-thermocouple' signed
  dt-bindings: iio: temperature: ltc2983: Fix child node unevaluated properties
  iio: addac: stx104: Use regmap_read_poll_timeout() for conversion poll
  iio: addac: stx104: Migrate to the regmap API
  iio: addac: stx104: Improve indentation in stx104_write_raw()
  iio: addac: stx104: Use define rather than hardcoded limit for write val
  iio: addac: stx104: Fix race condition when converting analog-to-digital
  iio: addac: stx104: Fix race condition for stx104_write_raw()
  dt-bindings: iio: st-sensors: Fix repeated text
  staging: iio: resolver: ads1210: fix config mode
  iio: adc: ti-ads1100: fix error code in probe()
  iio: accel: add support for IIS328DQ variant
  dt-bindings: iio: st-sensors: Add IIS328DQ accelerometer
  ...

2 files changed, 207 insertions, 7 deletions

diff --git a/include/linux/iio/iio-gts-helper.h b/include/linux/iio/iio-gts-helper.h
new file mode 100644
index 000000000000..dd64e544a3da
--- /dev/null
+++ b/include/linux/iio/iio-gts-helper.h
@@ -0,0 +1,206 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* gain-time-scale conversion helpers for IIO light sensors
+ *
+ * Copyright (c) 2023 Matti Vaittinen <mazziesaccount@gmail.com>
+ */
+
+#ifndef __IIO_GTS_HELPER__
+#define __IIO_GTS_HELPER__
+
+#include <linux/types.h>
+
+struct device;
+
+/**
+ * struct iio_gain_sel_pair - gain - selector values
+ *
+ * In many cases devices like light sensors allow setting signal amplification
+ * (gain) using a register interface. This structure describes amplification
+ * and corresponding selector (register value)
+ *
+ * @gain:	Gain (multiplication) value. Gain must be positive, negative
+ *		values are reserved for error handling.
+ * @sel:	Selector (usually register value) used to indicate this gain.
+ *		NOTE: Only selectors >= 0 supported.
+ */
+struct iio_gain_sel_pair {
+	int gain;
+	int sel;
+};
+
+/**
+ * struct iio_itime_sel_mul - integration time description
+ *
+ * In many cases devices like light sensors allow setting the duration of
+ * collecting data. Typically this duration has also an impact to the magnitude
+ * of measured values (gain). This structure describes the relation of
+ * integration time and amplification as well as corresponding selector
+ * (register value).
+ *
+ * An example could be a sensor allowing 50, 100, 200 and 400 mS times. The
+ * respective multiplication values could be 50 mS => 1, 100 mS => 2,
+ * 200 mS => 4 and 400 mS => 8 assuming the impact of integration time would be
+ * linear in a way that when collecting data for 50 mS caused value X, doubling
+ * the data collection time caused value 2X etc.
+ *
+ * @time_us:	Integration time in microseconds. Time values must be positive,
+ *		negative values are reserved for error handling.
+ * @sel:	Selector (usually register value) used to indicate this time
+ *		NOTE: Only selectors >= 0 supported.
+ * @mul:	Multiplication to the values caused by this time.
+ *		NOTE: Only multipliers > 0 supported.
+ */
+struct iio_itime_sel_mul {
+	int time_us;
+	int sel;
+	int mul;
+};
+
+struct iio_gts {
+	u64 max_scale;
+	const struct iio_gain_sel_pair *hwgain_table;
+	int num_hwgain;
+	const struct iio_itime_sel_mul *itime_table;
+	int num_itime;
+	int **per_time_avail_scale_tables;
+	int *avail_all_scales_table;
+	int num_avail_all_scales;
+	int *avail_time_tables;
+	int num_avail_time_tables;
+};
+
+#define GAIN_SCALE_GAIN(_gain, _sel)			\
+{							\
+	.gain = (_gain),				\
+	.sel = (_sel),					\
+}
+
+#define GAIN_SCALE_ITIME_US(_itime, _sel, _mul)		\
+{							\
+	.time_us = (_itime),				\
+	.sel = (_sel),					\
+	.mul = (_mul),					\
+}
+
+static inline const struct iio_itime_sel_mul *
+iio_gts_find_itime_by_time(struct iio_gts *gts, int time)
+{
+	int i;
+
+	if (!gts->num_itime)
+		return NULL;
+
+	for (i = 0; i < gts->num_itime; i++)
+		if (gts->itime_table[i].time_us == time)
+			return &gts->itime_table[i];
+
+	return NULL;
+}
+
+static inline const struct iio_itime_sel_mul *
+iio_gts_find_itime_by_sel(struct iio_gts *gts, int sel)
+{
+	int i;
+
+	for (i = 0; i < gts->num_itime; i++)
+		if (gts->itime_table[i].sel == sel)
+			return &gts->itime_table[i];
+
+	return NULL;
+}
+
+int devm_iio_init_iio_gts(struct device *dev, int max_scale_int, int max_scale_nano,
+			  const struct iio_gain_sel_pair *gain_tbl, int num_gain,
+			  const struct iio_itime_sel_mul *tim_tbl, int num_times,
+			  struct iio_gts *gts);
+/**
+ * iio_gts_find_int_time_by_sel - find integration time matching a selector
+ * @gts:	Gain time scale descriptor
+ * @sel:	selector for which matching integration time is searched for
+ *
+ * Return:	integration time matching given selector or -EINVAL if
+ *		integration time was not found.
+ */
+static inline int iio_gts_find_int_time_by_sel(struct iio_gts *gts, int sel)
+{
+	const struct iio_itime_sel_mul *itime;
+
+	itime = iio_gts_find_itime_by_sel(gts, sel);
+	if (!itime)
+		return -EINVAL;
+
+	return itime->time_us;
+}
+
+/**
+ * iio_gts_find_sel_by_int_time - find selector matching integration time
+ * @gts:	Gain time scale descriptor
+ * @gain:	HW-gain for which matching selector is searched for
+ *
+ * Return:	a selector matching given integration time or -EINVAL if
+ *		selector was not found.
+ */
+static inline int iio_gts_find_sel_by_int_time(struct iio_gts *gts, int time)
+{
+	const struct iio_itime_sel_mul *itime;
+
+	itime = iio_gts_find_itime_by_time(gts, time);
+	if (!itime)
+		return -EINVAL;
+
+	return itime->sel;
+}
+
+/**
+ * iio_gts_valid_time - check if given integration time is valid
+ * @gts:	Gain time scale descriptor
+ * @time_us:	Integration time to check
+ *
+ * Return:	True if given time is supported by device. False if not.
+ */
+static inline bool iio_gts_valid_time(struct iio_gts *gts, int time_us)
+{
+	return iio_gts_find_itime_by_time(gts, time_us) != NULL;
+}
+
+int iio_gts_find_sel_by_gain(struct iio_gts *gts, int gain);
+
+/**
+ * iio_gts_valid_gain - check if given HW-gain is valid
+ * @gts:	Gain time scale descriptor
+ * @gain:	HW-gain to check
+ *
+ * Return:	True if given time is supported by device. False if not.
+ */
+static inline bool iio_gts_valid_gain(struct iio_gts *gts, int gain)
+{
+	return iio_gts_find_sel_by_gain(gts, gain) >= 0;
+}
+
+int iio_find_closest_gain_low(struct iio_gts *gts, int gain, bool *in_range);
+int iio_gts_find_gain_by_sel(struct iio_gts *gts, int sel);
+int iio_gts_get_min_gain(struct iio_gts *gts);
+int iio_gts_find_int_time_by_sel(struct iio_gts *gts, int sel);
+int iio_gts_find_sel_by_int_time(struct iio_gts *gts, int time);
+
+int iio_gts_total_gain_to_scale(struct iio_gts *gts, int total_gain,
+				int *scale_int, int *scale_nano);
+int iio_gts_find_gain_sel_for_scale_using_time(struct iio_gts *gts, int time_sel,
+					       int scale_int, int scale_nano,
+					       int *gain_sel);
+int iio_gts_get_scale(struct iio_gts *gts, int gain, int time, int *scale_int,
+		      int *scale_nano);
+int iio_gts_find_new_gain_sel_by_old_gain_time(struct iio_gts *gts,
+					       int old_gain, int old_time_sel,
+					       int new_time_sel, int *new_gain);
+int iio_gts_find_new_gain_by_old_gain_time(struct iio_gts *gts, int old_gain,
+					   int old_time, int new_time,
+					   int *new_gain);
+int iio_gts_avail_times(struct iio_gts *gts,  const int **vals, int *type,
+			int *length);
+int iio_gts_all_avail_scales(struct iio_gts *gts, const int **vals, int *type,
+			     int *length);
+int iio_gts_avail_scales_for_time(struct iio_gts *gts, int time,
+				  const int **vals, int *type, int *length);
+
+#endif
diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h
index f6360d9a492d..51f52c5c6092 100644
--- a/include/linux/iio/trigger.h
+++ b/include/linux/iio/trigger.h
@@ -151,14 +151,8 @@ void iio_trigger_unregister(struct iio_trigger *trig_info);
  **/
 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
 
-/**
- * iio_trigger_poll() - called on a trigger occurring
- * @trig:	trigger which occurred
- *
- * Typically called in relevant hardware interrupt handler.
- **/
 void iio_trigger_poll(struct iio_trigger *trig);
-void iio_trigger_poll_chained(struct iio_trigger *trig);
+void iio_trigger_poll_nested(struct iio_trigger *trig);
 
 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);