955 lines
24 KiB
C
955 lines
24 KiB
C
/*
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* Driver for the Asahi Kasei EMD Corporation AK8974
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* and Aichi Steel AMI305 magnetometer chips.
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* Based on a patch from Samu Onkalo and the AK8975 IIO driver.
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*
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* Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
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* Copyright (c) 2010 NVIDIA Corporation.
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* Copyright (C) 2016 Linaro Ltd.
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*
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* Author: Samu Onkalo <samu.p.onkalo@nokia.com>
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* Author: Linus Walleij <linus.walleij@linaro.org>
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h> /* For irq_get_irq_data() */
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#include <linux/completion.h>
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#include <linux/err.h>
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#include <linux/mutex.h>
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#include <linux/delay.h>
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#include <linux/bitops.h>
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#include <linux/random.h>
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#include <linux/regmap.h>
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#include <linux/regulator/consumer.h>
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#include <linux/pm_runtime.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/sysfs.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/trigger.h>
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#include <linux/iio/trigger_consumer.h>
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#include <linux/iio/triggered_buffer.h>
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/*
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* 16-bit registers are little-endian. LSB is at the address defined below
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* and MSB is at the next higher address.
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*/
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/* These registers are common for AK8974 and AMI30x */
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#define AK8974_SELFTEST 0x0C
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#define AK8974_SELFTEST_IDLE 0x55
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#define AK8974_SELFTEST_OK 0xAA
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#define AK8974_INFO 0x0D
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#define AK8974_WHOAMI 0x0F
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#define AK8974_WHOAMI_VALUE_AMI306 0x46
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#define AK8974_WHOAMI_VALUE_AMI305 0x47
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#define AK8974_WHOAMI_VALUE_AK8974 0x48
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#define AK8974_DATA_X 0x10
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#define AK8974_DATA_Y 0x12
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#define AK8974_DATA_Z 0x14
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#define AK8974_INT_SRC 0x16
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#define AK8974_STATUS 0x18
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#define AK8974_INT_CLEAR 0x1A
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#define AK8974_CTRL1 0x1B
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#define AK8974_CTRL2 0x1C
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#define AK8974_CTRL3 0x1D
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#define AK8974_INT_CTRL 0x1E
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#define AK8974_INT_THRES 0x26 /* Absolute any axis value threshold */
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#define AK8974_PRESET 0x30
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/* AK8974-specific offsets */
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#define AK8974_OFFSET_X 0x20
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#define AK8974_OFFSET_Y 0x22
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#define AK8974_OFFSET_Z 0x24
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/* AMI305-specific offsets */
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#define AMI305_OFFSET_X 0x6C
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#define AMI305_OFFSET_Y 0x72
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#define AMI305_OFFSET_Z 0x78
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/* Different temperature registers */
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#define AK8974_TEMP 0x31
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#define AMI305_TEMP 0x60
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/* AMI306-specific control register */
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#define AMI306_CTRL4 0x5C
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/* AMI306 factory calibration data */
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/* fine axis sensitivity */
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#define AMI306_FINEOUTPUT_X 0x90
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#define AMI306_FINEOUTPUT_Y 0x92
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#define AMI306_FINEOUTPUT_Z 0x94
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/* axis sensitivity */
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#define AMI306_SENS_X 0x96
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#define AMI306_SENS_Y 0x98
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#define AMI306_SENS_Z 0x9A
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/* axis cross-interference */
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#define AMI306_GAIN_PARA_XZ 0x9C
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#define AMI306_GAIN_PARA_XY 0x9D
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#define AMI306_GAIN_PARA_YZ 0x9E
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#define AMI306_GAIN_PARA_YX 0x9F
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#define AMI306_GAIN_PARA_ZY 0xA0
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#define AMI306_GAIN_PARA_ZX 0xA1
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/* offset at ZERO magnetic field */
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#define AMI306_OFFZERO_X 0xF8
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#define AMI306_OFFZERO_Y 0xFA
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#define AMI306_OFFZERO_Z 0xFC
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#define AK8974_INT_X_HIGH BIT(7) /* Axis over +threshold */
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#define AK8974_INT_Y_HIGH BIT(6)
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#define AK8974_INT_Z_HIGH BIT(5)
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#define AK8974_INT_X_LOW BIT(4) /* Axis below -threshold */
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#define AK8974_INT_Y_LOW BIT(3)
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#define AK8974_INT_Z_LOW BIT(2)
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#define AK8974_INT_RANGE BIT(1) /* Range overflow (any axis) */
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#define AK8974_STATUS_DRDY BIT(6) /* Data ready */
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#define AK8974_STATUS_OVERRUN BIT(5) /* Data overrun */
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#define AK8974_STATUS_INT BIT(4) /* Interrupt occurred */
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#define AK8974_CTRL1_POWER BIT(7) /* 0 = standby; 1 = active */
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#define AK8974_CTRL1_RATE BIT(4) /* 0 = 10 Hz; 1 = 20 Hz */
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#define AK8974_CTRL1_FORCE_EN BIT(1) /* 0 = normal; 1 = force */
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#define AK8974_CTRL1_MODE2 BIT(0) /* 0 */
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#define AK8974_CTRL2_INT_EN BIT(4) /* 1 = enable interrupts */
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#define AK8974_CTRL2_DRDY_EN BIT(3) /* 1 = enable data ready signal */
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#define AK8974_CTRL2_DRDY_POL BIT(2) /* 1 = data ready active high */
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#define AK8974_CTRL2_RESDEF (AK8974_CTRL2_DRDY_POL)
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#define AK8974_CTRL3_RESET BIT(7) /* Software reset */
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#define AK8974_CTRL3_FORCE BIT(6) /* Start forced measurement */
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#define AK8974_CTRL3_SELFTEST BIT(4) /* Set selftest register */
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#define AK8974_CTRL3_RESDEF 0x00
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#define AK8974_INT_CTRL_XEN BIT(7) /* Enable interrupt for this axis */
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#define AK8974_INT_CTRL_YEN BIT(6)
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#define AK8974_INT_CTRL_ZEN BIT(5)
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#define AK8974_INT_CTRL_XYZEN (BIT(7)|BIT(6)|BIT(5))
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#define AK8974_INT_CTRL_POL BIT(3) /* 0 = active low; 1 = active high */
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#define AK8974_INT_CTRL_PULSE BIT(1) /* 0 = latched; 1 = pulse (50 usec) */
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#define AK8974_INT_CTRL_RESDEF (AK8974_INT_CTRL_XYZEN | AK8974_INT_CTRL_POL)
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/* The AMI305 has elaborate FW version and serial number registers */
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#define AMI305_VER 0xE8
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#define AMI305_SN 0xEA
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#define AK8974_MAX_RANGE 2048
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#define AK8974_POWERON_DELAY 50
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#define AK8974_ACTIVATE_DELAY 1
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#define AK8974_SELFTEST_DELAY 1
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/*
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* Set the autosuspend to two orders of magnitude larger than the poweron
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* delay to make sane reasonable power tradeoff savings (5 seconds in
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* this case).
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*/
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#define AK8974_AUTOSUSPEND_DELAY 5000
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#define AK8974_MEASTIME 3
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#define AK8974_PWR_ON 1
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#define AK8974_PWR_OFF 0
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/**
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* struct ak8974 - state container for the AK8974 driver
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* @i2c: parent I2C client
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* @orientation: mounting matrix, flipped axis etc
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* @map: regmap to access the AK8974 registers over I2C
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* @regs: the avdd and dvdd power regulators
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* @name: the name of the part
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* @variant: the whoami ID value (for selecting code paths)
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* @lock: locks the magnetometer for exclusive use during a measurement
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* @drdy_irq: uses the DRDY IRQ line
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* @drdy_complete: completion for DRDY
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* @drdy_active_low: the DRDY IRQ is active low
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*/
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struct ak8974 {
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struct i2c_client *i2c;
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struct iio_mount_matrix orientation;
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struct regmap *map;
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struct regulator_bulk_data regs[2];
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const char *name;
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u8 variant;
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struct mutex lock;
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bool drdy_irq;
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struct completion drdy_complete;
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bool drdy_active_low;
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};
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static const char ak8974_reg_avdd[] = "avdd";
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static const char ak8974_reg_dvdd[] = "dvdd";
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static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val)
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{
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int ret;
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__le16 bulk;
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ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2);
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if (ret)
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return ret;
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*val = le16_to_cpu(bulk);
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return 0;
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}
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static int ak8974_set_u16_val(struct ak8974 *ak8974, u8 reg, u16 val)
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{
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__le16 bulk = cpu_to_le16(val);
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return regmap_bulk_write(ak8974->map, reg, &bulk, 2);
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}
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static int ak8974_set_power(struct ak8974 *ak8974, bool mode)
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{
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int ret;
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u8 val;
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val = mode ? AK8974_CTRL1_POWER : 0;
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val |= AK8974_CTRL1_FORCE_EN;
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ret = regmap_write(ak8974->map, AK8974_CTRL1, val);
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if (ret < 0)
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return ret;
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if (mode)
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msleep(AK8974_ACTIVATE_DELAY);
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return 0;
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}
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static int ak8974_reset(struct ak8974 *ak8974)
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{
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int ret;
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/* Power on to get register access. Sets CTRL1 reg to reset state */
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ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
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if (ret)
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return ret;
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ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_RESDEF);
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if (ret)
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return ret;
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ret = regmap_write(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_RESDEF);
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if (ret)
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return ret;
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ret = regmap_write(ak8974->map, AK8974_INT_CTRL,
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AK8974_INT_CTRL_RESDEF);
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if (ret)
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return ret;
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/* After reset, power off is default state */
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return ak8974_set_power(ak8974, AK8974_PWR_OFF);
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}
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static int ak8974_configure(struct ak8974 *ak8974)
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{
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int ret;
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ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_DRDY_EN |
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AK8974_CTRL2_INT_EN);
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if (ret)
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return ret;
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ret = regmap_write(ak8974->map, AK8974_CTRL3, 0);
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if (ret)
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return ret;
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if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI306) {
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/* magic from datasheet: set high-speed measurement mode */
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ret = ak8974_set_u16_val(ak8974, AMI306_CTRL4, 0xA07E);
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if (ret)
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return ret;
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}
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ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_POL);
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if (ret)
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return ret;
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return regmap_write(ak8974->map, AK8974_PRESET, 0);
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}
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static int ak8974_trigmeas(struct ak8974 *ak8974)
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{
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unsigned int clear;
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u8 mask;
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u8 val;
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int ret;
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/* Clear any previous measurement overflow status */
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ret = regmap_read(ak8974->map, AK8974_INT_CLEAR, &clear);
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if (ret)
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return ret;
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/* If we have a DRDY IRQ line, use it */
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if (ak8974->drdy_irq) {
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mask = AK8974_CTRL2_INT_EN |
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AK8974_CTRL2_DRDY_EN |
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AK8974_CTRL2_DRDY_POL;
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val = AK8974_CTRL2_DRDY_EN;
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if (!ak8974->drdy_active_low)
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val |= AK8974_CTRL2_DRDY_POL;
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init_completion(&ak8974->drdy_complete);
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ret = regmap_update_bits(ak8974->map, AK8974_CTRL2,
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mask, val);
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if (ret)
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return ret;
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}
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/* Force a measurement */
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return regmap_update_bits(ak8974->map,
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AK8974_CTRL3,
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AK8974_CTRL3_FORCE,
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AK8974_CTRL3_FORCE);
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}
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static int ak8974_await_drdy(struct ak8974 *ak8974)
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{
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int timeout = 2;
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unsigned int val;
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int ret;
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if (ak8974->drdy_irq) {
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ret = wait_for_completion_timeout(&ak8974->drdy_complete,
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1 + msecs_to_jiffies(1000));
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if (!ret) {
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dev_err(&ak8974->i2c->dev,
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"timeout waiting for DRDY IRQ\n");
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return -ETIMEDOUT;
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}
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return 0;
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}
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/* Default delay-based poll loop */
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do {
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msleep(AK8974_MEASTIME);
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ret = regmap_read(ak8974->map, AK8974_STATUS, &val);
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if (ret < 0)
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return ret;
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if (val & AK8974_STATUS_DRDY)
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return 0;
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} while (--timeout);
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dev_err(&ak8974->i2c->dev, "timeout waiting for DRDY\n");
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return -ETIMEDOUT;
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}
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static int ak8974_getresult(struct ak8974 *ak8974, __le16 *result)
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{
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unsigned int src;
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int ret;
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ret = ak8974_await_drdy(ak8974);
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if (ret)
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return ret;
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ret = regmap_read(ak8974->map, AK8974_INT_SRC, &src);
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if (ret < 0)
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return ret;
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/* Out of range overflow! Strong magnet close? */
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if (src & AK8974_INT_RANGE) {
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dev_err(&ak8974->i2c->dev,
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"range overflow in sensor\n");
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return -ERANGE;
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}
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ret = regmap_bulk_read(ak8974->map, AK8974_DATA_X, result, 6);
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if (ret)
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return ret;
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return ret;
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}
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static irqreturn_t ak8974_drdy_irq(int irq, void *d)
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{
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struct ak8974 *ak8974 = d;
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if (!ak8974->drdy_irq)
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return IRQ_NONE;
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/* TODO: timestamp here to get good measurement stamps */
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return IRQ_WAKE_THREAD;
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}
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static irqreturn_t ak8974_drdy_irq_thread(int irq, void *d)
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{
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struct ak8974 *ak8974 = d;
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unsigned int val;
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int ret;
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/* Check if this was a DRDY from us */
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ret = regmap_read(ak8974->map, AK8974_STATUS, &val);
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if (ret < 0) {
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dev_err(&ak8974->i2c->dev, "error reading DRDY status\n");
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return IRQ_HANDLED;
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}
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if (val & AK8974_STATUS_DRDY) {
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/* Yes this was our IRQ */
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complete(&ak8974->drdy_complete);
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return IRQ_HANDLED;
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}
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/* We may be on a shared IRQ, let the next client check */
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return IRQ_NONE;
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}
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static int ak8974_selftest(struct ak8974 *ak8974)
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{
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struct device *dev = &ak8974->i2c->dev;
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unsigned int val;
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int ret;
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ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
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if (ret)
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return ret;
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if (val != AK8974_SELFTEST_IDLE) {
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dev_err(dev, "selftest not idle before test\n");
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return -EIO;
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}
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/* Trigger self-test */
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ret = regmap_update_bits(ak8974->map,
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AK8974_CTRL3,
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AK8974_CTRL3_SELFTEST,
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AK8974_CTRL3_SELFTEST);
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if (ret) {
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dev_err(dev, "could not write CTRL3\n");
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return ret;
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}
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msleep(AK8974_SELFTEST_DELAY);
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ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
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if (ret)
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return ret;
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if (val != AK8974_SELFTEST_OK) {
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dev_err(dev, "selftest result NOT OK (%02x)\n", val);
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return -EIO;
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}
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ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
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if (ret)
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return ret;
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if (val != AK8974_SELFTEST_IDLE) {
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dev_err(dev, "selftest not idle after test (%02x)\n", val);
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return -EIO;
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}
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dev_dbg(dev, "passed self-test\n");
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return 0;
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}
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static void ak8974_read_calib_data(struct ak8974 *ak8974, unsigned int reg,
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__le16 *tab, size_t tab_size)
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{
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int ret = regmap_bulk_read(ak8974->map, reg, tab, tab_size);
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if (ret) {
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memset(tab, 0xFF, tab_size);
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dev_warn(&ak8974->i2c->dev,
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"can't read calibration data (regs %u..%zu): %d\n",
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reg, reg + tab_size - 1, ret);
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} else {
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add_device_randomness(tab, tab_size);
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}
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}
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static int ak8974_detect(struct ak8974 *ak8974)
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{
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unsigned int whoami;
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const char *name;
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int ret;
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unsigned int fw;
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u16 sn;
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ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami);
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if (ret)
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return ret;
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name = "ami305";
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switch (whoami) {
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case AK8974_WHOAMI_VALUE_AMI306:
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name = "ami306";
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/* fall-through */
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case AK8974_WHOAMI_VALUE_AMI305:
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ret = regmap_read(ak8974->map, AMI305_VER, &fw);
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if (ret)
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return ret;
|
|
fw &= 0x7f; /* only bits 0 thru 6 valid */
|
|
ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn);
|
|
if (ret)
|
|
return ret;
|
|
add_device_randomness(&sn, sizeof(sn));
|
|
dev_info(&ak8974->i2c->dev,
|
|
"detected %s, FW ver %02x, S/N: %04x\n",
|
|
name, fw, sn);
|
|
break;
|
|
case AK8974_WHOAMI_VALUE_AK8974:
|
|
name = "ak8974";
|
|
dev_info(&ak8974->i2c->dev, "detected AK8974\n");
|
|
break;
|
|
default:
|
|
dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ",
|
|
whoami);
|
|
return -ENODEV;
|
|
}
|
|
|
|
ak8974->name = name;
|
|
ak8974->variant = whoami;
|
|
|
|
if (whoami == AK8974_WHOAMI_VALUE_AMI306) {
|
|
__le16 fab_data1[9], fab_data2[3];
|
|
int i;
|
|
|
|
ak8974_read_calib_data(ak8974, AMI306_FINEOUTPUT_X,
|
|
fab_data1, sizeof(fab_data1));
|
|
ak8974_read_calib_data(ak8974, AMI306_OFFZERO_X,
|
|
fab_data2, sizeof(fab_data2));
|
|
|
|
for (i = 0; i < 3; ++i) {
|
|
static const char axis[3] = "XYZ";
|
|
static const char pgaxis[6] = "ZYZXYX";
|
|
unsigned offz = le16_to_cpu(fab_data2[i]) & 0x7F;
|
|
unsigned fine = le16_to_cpu(fab_data1[i]);
|
|
unsigned sens = le16_to_cpu(fab_data1[i + 3]);
|
|
unsigned pgain1 = le16_to_cpu(fab_data1[i + 6]);
|
|
unsigned pgain2 = pgain1 >> 8;
|
|
|
|
pgain1 &= 0xFF;
|
|
|
|
dev_info(&ak8974->i2c->dev,
|
|
"factory calibration for axis %c: offz=%u sens=%u fine=%u pga%c=%u pga%c=%u\n",
|
|
axis[i], offz, sens, fine, pgaxis[i * 2],
|
|
pgain1, pgaxis[i * 2 + 1], pgain2);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ak8974_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2,
|
|
long mask)
|
|
{
|
|
struct ak8974 *ak8974 = iio_priv(indio_dev);
|
|
__le16 hw_values[3];
|
|
int ret = -EINVAL;
|
|
|
|
pm_runtime_get_sync(&ak8974->i2c->dev);
|
|
mutex_lock(&ak8974->lock);
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_RAW:
|
|
if (chan->address > 2) {
|
|
dev_err(&ak8974->i2c->dev, "faulty channel address\n");
|
|
ret = -EIO;
|
|
goto out_unlock;
|
|
}
|
|
ret = ak8974_trigmeas(ak8974);
|
|
if (ret)
|
|
goto out_unlock;
|
|
ret = ak8974_getresult(ak8974, hw_values);
|
|
if (ret)
|
|
goto out_unlock;
|
|
|
|
/*
|
|
* We read all axes and discard all but one, for optimized
|
|
* reading, use the triggered buffer.
|
|
*/
|
|
*val = le16_to_cpu(hw_values[chan->address]);
|
|
|
|
ret = IIO_VAL_INT;
|
|
}
|
|
|
|
out_unlock:
|
|
mutex_unlock(&ak8974->lock);
|
|
pm_runtime_mark_last_busy(&ak8974->i2c->dev);
|
|
pm_runtime_put_autosuspend(&ak8974->i2c->dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void ak8974_fill_buffer(struct iio_dev *indio_dev)
|
|
{
|
|
struct ak8974 *ak8974 = iio_priv(indio_dev);
|
|
int ret;
|
|
__le16 hw_values[8]; /* Three axes + 64bit padding */
|
|
|
|
pm_runtime_get_sync(&ak8974->i2c->dev);
|
|
mutex_lock(&ak8974->lock);
|
|
|
|
ret = ak8974_trigmeas(ak8974);
|
|
if (ret) {
|
|
dev_err(&ak8974->i2c->dev, "error triggering measure\n");
|
|
goto out_unlock;
|
|
}
|
|
ret = ak8974_getresult(ak8974, hw_values);
|
|
if (ret) {
|
|
dev_err(&ak8974->i2c->dev, "error getting measures\n");
|
|
goto out_unlock;
|
|
}
|
|
|
|
iio_push_to_buffers_with_timestamp(indio_dev, hw_values,
|
|
iio_get_time_ns(indio_dev));
|
|
|
|
out_unlock:
|
|
mutex_unlock(&ak8974->lock);
|
|
pm_runtime_mark_last_busy(&ak8974->i2c->dev);
|
|
pm_runtime_put_autosuspend(&ak8974->i2c->dev);
|
|
}
|
|
|
|
static irqreturn_t ak8974_handle_trigger(int irq, void *p)
|
|
{
|
|
const struct iio_poll_func *pf = p;
|
|
struct iio_dev *indio_dev = pf->indio_dev;
|
|
|
|
ak8974_fill_buffer(indio_dev);
|
|
iio_trigger_notify_done(indio_dev->trig);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static const struct iio_mount_matrix *
|
|
ak8974_get_mount_matrix(const struct iio_dev *indio_dev,
|
|
const struct iio_chan_spec *chan)
|
|
{
|
|
struct ak8974 *ak8974 = iio_priv(indio_dev);
|
|
|
|
return &ak8974->orientation;
|
|
}
|
|
|
|
static const struct iio_chan_spec_ext_info ak8974_ext_info[] = {
|
|
IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8974_get_mount_matrix),
|
|
{ },
|
|
};
|
|
|
|
#define AK8974_AXIS_CHANNEL(axis, index) \
|
|
{ \
|
|
.type = IIO_MAGN, \
|
|
.modified = 1, \
|
|
.channel2 = IIO_MOD_##axis, \
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
|
|
.ext_info = ak8974_ext_info, \
|
|
.address = index, \
|
|
.scan_index = index, \
|
|
.scan_type = { \
|
|
.sign = 's', \
|
|
.realbits = 16, \
|
|
.storagebits = 16, \
|
|
.endianness = IIO_LE \
|
|
}, \
|
|
}
|
|
|
|
static const struct iio_chan_spec ak8974_channels[] = {
|
|
AK8974_AXIS_CHANNEL(X, 0),
|
|
AK8974_AXIS_CHANNEL(Y, 1),
|
|
AK8974_AXIS_CHANNEL(Z, 2),
|
|
IIO_CHAN_SOFT_TIMESTAMP(3),
|
|
};
|
|
|
|
static const unsigned long ak8974_scan_masks[] = { 0x7, 0 };
|
|
|
|
static const struct iio_info ak8974_info = {
|
|
.read_raw = &ak8974_read_raw,
|
|
};
|
|
|
|
static bool ak8974_writeable_reg(struct device *dev, unsigned int reg)
|
|
{
|
|
struct i2c_client *i2c = to_i2c_client(dev);
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
|
|
struct ak8974 *ak8974 = iio_priv(indio_dev);
|
|
|
|
switch (reg) {
|
|
case AK8974_CTRL1:
|
|
case AK8974_CTRL2:
|
|
case AK8974_CTRL3:
|
|
case AK8974_INT_CTRL:
|
|
case AK8974_INT_THRES:
|
|
case AK8974_INT_THRES + 1:
|
|
case AK8974_PRESET:
|
|
case AK8974_PRESET + 1:
|
|
return true;
|
|
case AK8974_OFFSET_X:
|
|
case AK8974_OFFSET_X + 1:
|
|
case AK8974_OFFSET_Y:
|
|
case AK8974_OFFSET_Y + 1:
|
|
case AK8974_OFFSET_Z:
|
|
case AK8974_OFFSET_Z + 1:
|
|
if (ak8974->variant == AK8974_WHOAMI_VALUE_AK8974)
|
|
return true;
|
|
return false;
|
|
case AMI305_OFFSET_X:
|
|
case AMI305_OFFSET_X + 1:
|
|
case AMI305_OFFSET_Y:
|
|
case AMI305_OFFSET_Y + 1:
|
|
case AMI305_OFFSET_Z:
|
|
case AMI305_OFFSET_Z + 1:
|
|
return ak8974->variant == AK8974_WHOAMI_VALUE_AMI305 ||
|
|
ak8974->variant == AK8974_WHOAMI_VALUE_AMI306;
|
|
case AMI306_CTRL4:
|
|
case AMI306_CTRL4 + 1:
|
|
return ak8974->variant == AK8974_WHOAMI_VALUE_AMI306;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
static bool ak8974_precious_reg(struct device *dev, unsigned int reg)
|
|
{
|
|
return reg == AK8974_INT_CLEAR;
|
|
}
|
|
|
|
static const struct regmap_config ak8974_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
.max_register = 0xff,
|
|
.writeable_reg = ak8974_writeable_reg,
|
|
.precious_reg = ak8974_precious_reg,
|
|
};
|
|
|
|
static int ak8974_probe(struct i2c_client *i2c,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct iio_dev *indio_dev;
|
|
struct ak8974 *ak8974;
|
|
unsigned long irq_trig;
|
|
int irq = i2c->irq;
|
|
int ret;
|
|
|
|
/* Register with IIO */
|
|
indio_dev = devm_iio_device_alloc(&i2c->dev, sizeof(*ak8974));
|
|
if (indio_dev == NULL)
|
|
return -ENOMEM;
|
|
|
|
ak8974 = iio_priv(indio_dev);
|
|
i2c_set_clientdata(i2c, indio_dev);
|
|
ak8974->i2c = i2c;
|
|
mutex_init(&ak8974->lock);
|
|
|
|
ret = of_iio_read_mount_matrix(&i2c->dev,
|
|
"mount-matrix",
|
|
&ak8974->orientation);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ak8974->regs[0].supply = ak8974_reg_avdd;
|
|
ak8974->regs[1].supply = ak8974_reg_dvdd;
|
|
|
|
ret = devm_regulator_bulk_get(&i2c->dev,
|
|
ARRAY_SIZE(ak8974->regs),
|
|
ak8974->regs);
|
|
if (ret < 0) {
|
|
dev_err(&i2c->dev, "cannot get regulators\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
if (ret < 0) {
|
|
dev_err(&i2c->dev, "cannot enable regulators\n");
|
|
return ret;
|
|
}
|
|
|
|
/* Take runtime PM online */
|
|
pm_runtime_get_noresume(&i2c->dev);
|
|
pm_runtime_set_active(&i2c->dev);
|
|
pm_runtime_enable(&i2c->dev);
|
|
|
|
ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config);
|
|
if (IS_ERR(ak8974->map)) {
|
|
dev_err(&i2c->dev, "failed to allocate register map\n");
|
|
return PTR_ERR(ak8974->map);
|
|
}
|
|
|
|
ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "could not power on\n");
|
|
goto power_off;
|
|
}
|
|
|
|
ret = ak8974_detect(ak8974);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "neither AK8974 nor AMI30x found\n");
|
|
goto power_off;
|
|
}
|
|
|
|
ret = ak8974_selftest(ak8974);
|
|
if (ret)
|
|
dev_err(&i2c->dev, "selftest failed (continuing anyway)\n");
|
|
|
|
ret = ak8974_reset(ak8974);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "AK8974 reset failed\n");
|
|
goto power_off;
|
|
}
|
|
|
|
pm_runtime_set_autosuspend_delay(&i2c->dev,
|
|
AK8974_AUTOSUSPEND_DELAY);
|
|
pm_runtime_use_autosuspend(&i2c->dev);
|
|
pm_runtime_put(&i2c->dev);
|
|
|
|
indio_dev->dev.parent = &i2c->dev;
|
|
indio_dev->channels = ak8974_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(ak8974_channels);
|
|
indio_dev->info = &ak8974_info;
|
|
indio_dev->available_scan_masks = ak8974_scan_masks;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->name = ak8974->name;
|
|
|
|
ret = iio_triggered_buffer_setup(indio_dev, NULL,
|
|
ak8974_handle_trigger,
|
|
NULL);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "triggered buffer setup failed\n");
|
|
goto disable_pm;
|
|
}
|
|
|
|
/* If we have a valid DRDY IRQ, make use of it */
|
|
if (irq > 0) {
|
|
irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
|
|
if (irq_trig == IRQF_TRIGGER_RISING) {
|
|
dev_info(&i2c->dev, "enable rising edge DRDY IRQ\n");
|
|
} else if (irq_trig == IRQF_TRIGGER_FALLING) {
|
|
ak8974->drdy_active_low = true;
|
|
dev_info(&i2c->dev, "enable falling edge DRDY IRQ\n");
|
|
} else {
|
|
irq_trig = IRQF_TRIGGER_RISING;
|
|
}
|
|
irq_trig |= IRQF_ONESHOT;
|
|
irq_trig |= IRQF_SHARED;
|
|
|
|
ret = devm_request_threaded_irq(&i2c->dev,
|
|
irq,
|
|
ak8974_drdy_irq,
|
|
ak8974_drdy_irq_thread,
|
|
irq_trig,
|
|
ak8974->name,
|
|
ak8974);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "unable to request DRDY IRQ "
|
|
"- proceeding without IRQ\n");
|
|
goto no_irq;
|
|
}
|
|
ak8974->drdy_irq = true;
|
|
}
|
|
|
|
no_irq:
|
|
ret = iio_device_register(indio_dev);
|
|
if (ret) {
|
|
dev_err(&i2c->dev, "device register failed\n");
|
|
goto cleanup_buffer;
|
|
}
|
|
|
|
return 0;
|
|
|
|
cleanup_buffer:
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
disable_pm:
|
|
pm_runtime_put_noidle(&i2c->dev);
|
|
pm_runtime_disable(&i2c->dev);
|
|
ak8974_set_power(ak8974, AK8974_PWR_OFF);
|
|
power_off:
|
|
regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int ak8974_remove(struct i2c_client *i2c)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
|
|
struct ak8974 *ak8974 = iio_priv(indio_dev);
|
|
|
|
iio_device_unregister(indio_dev);
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
pm_runtime_get_sync(&i2c->dev);
|
|
pm_runtime_put_noidle(&i2c->dev);
|
|
pm_runtime_disable(&i2c->dev);
|
|
ak8974_set_power(ak8974, AK8974_PWR_OFF);
|
|
regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused ak8974_runtime_suspend(struct device *dev)
|
|
{
|
|
struct ak8974 *ak8974 =
|
|
iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
|
|
ak8974_set_power(ak8974, AK8974_PWR_OFF);
|
|
regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused ak8974_runtime_resume(struct device *dev)
|
|
{
|
|
struct ak8974 *ak8974 =
|
|
iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
int ret;
|
|
|
|
ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
if (ret)
|
|
return ret;
|
|
msleep(AK8974_POWERON_DELAY);
|
|
ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
|
|
if (ret)
|
|
goto out_regulator_disable;
|
|
|
|
ret = ak8974_configure(ak8974);
|
|
if (ret)
|
|
goto out_disable_power;
|
|
|
|
return 0;
|
|
|
|
out_disable_power:
|
|
ak8974_set_power(ak8974, AK8974_PWR_OFF);
|
|
out_regulator_disable:
|
|
regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct dev_pm_ops ak8974_dev_pm_ops = {
|
|
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
|
|
pm_runtime_force_resume)
|
|
SET_RUNTIME_PM_OPS(ak8974_runtime_suspend,
|
|
ak8974_runtime_resume, NULL)
|
|
};
|
|
|
|
static const struct i2c_device_id ak8974_id[] = {
|
|
{"ami305", 0 },
|
|
{"ami306", 0 },
|
|
{"ak8974", 0 },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ak8974_id);
|
|
|
|
static const struct of_device_id ak8974_of_match[] = {
|
|
{ .compatible = "asahi-kasei,ak8974", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ak8974_of_match);
|
|
|
|
static struct i2c_driver ak8974_driver = {
|
|
.driver = {
|
|
.name = "ak8974",
|
|
.pm = &ak8974_dev_pm_ops,
|
|
.of_match_table = of_match_ptr(ak8974_of_match),
|
|
},
|
|
.probe = ak8974_probe,
|
|
.remove = ak8974_remove,
|
|
.id_table = ak8974_id,
|
|
};
|
|
module_i2c_driver(ak8974_driver);
|
|
|
|
MODULE_DESCRIPTION("AK8974 and AMI30x 3-axis magnetometer driver");
|
|
MODULE_AUTHOR("Samu Onkalo");
|
|
MODULE_AUTHOR("Linus Walleij");
|
|
MODULE_LICENSE("GPL v2");
|