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1066 lines
27 KiB
1066 lines
27 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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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 <[email protected]> |
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* Author: Linus Walleij <[email protected]> |
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*/ |
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#include <linux/module.h> |
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#include <linux/mod_devicetable.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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|
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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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/* |
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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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|
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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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|
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#define AK8974_INFO 0x0D |
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|
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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_WHOAMI_VALUE_HSCDTD008A 0x49 |
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|
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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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|
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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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|
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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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|
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/* AMI306-specific control register */ |
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#define AMI306_CTRL4 0x5C |
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|
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/* AMI306 factory calibration data */ |
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|
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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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|
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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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|
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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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|
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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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|
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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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/* HSCDTD008A-specific control register */ |
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#define HSCDTD008A_CTRL4 0x1E |
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#define HSCDTD008A_CTRL4_MMD BIT(7) /* must be set to 1 */ |
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#define HSCDTD008A_CTRL4_RANGE BIT(4) /* 0 = 14-bit output; 1 = 15-bit output */ |
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#define HSCDTD008A_CTRL4_RESDEF (HSCDTD008A_CTRL4_MMD | HSCDTD008A_CTRL4_RANGE) |
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|
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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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|
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#define AK8974_MAX_RANGE 2048 |
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|
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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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|
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#define AK8974_MEASTIME 3 |
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|
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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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/** |
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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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* @scan: timestamps |
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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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/* Ensure timestamp is naturally aligned */ |
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struct { |
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__le16 channels[3]; |
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s64 ts __aligned(8); |
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} scan; |
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}; |
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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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|
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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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|
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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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|
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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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|
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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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|
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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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if (ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A) { |
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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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} else { |
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ret = regmap_write(ak8974->map, HSCDTD008A_CTRL4, |
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HSCDTD008A_CTRL4_RESDEF); |
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if (ret) |
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return ret; |
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} |
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|
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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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if (ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A) |
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return 0; |
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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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|
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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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|
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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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|
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if (!ak8974->drdy_active_low) |
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val |= AK8974_CTRL2_DRDY_POL; |
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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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fallthrough; |
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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; |
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fw &= 0x7f; /* only bits 0 thru 6 valid */ |
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ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn); |
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if (ret) |
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return ret; |
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add_device_randomness(&sn, sizeof(sn)); |
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dev_info(&ak8974->i2c->dev, |
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"detected %s, FW ver %02x, S/N: %04x\n", |
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name, fw, sn); |
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break; |
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case AK8974_WHOAMI_VALUE_AK8974: |
|
name = "ak8974"; |
|
dev_info(&ak8974->i2c->dev, "detected AK8974\n"); |
|
break; |
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case AK8974_WHOAMI_VALUE_HSCDTD008A: |
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name = "hscdtd008a"; |
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dev_info(&ak8974->i2c->dev, "detected hscdtd008a\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_measure_channel(struct ak8974 *ak8974, unsigned long address, |
|
int *val) |
|
{ |
|
__le16 hw_values[3]; |
|
int ret; |
|
|
|
pm_runtime_get_sync(&ak8974->i2c->dev); |
|
mutex_lock(&ak8974->lock); |
|
|
|
/* |
|
* We read all axes and discard all but one, for optimized |
|
* reading, use the triggered buffer. |
|
*/ |
|
ret = ak8974_trigmeas(ak8974); |
|
if (ret) |
|
goto out_unlock; |
|
ret = ak8974_getresult(ak8974, hw_values); |
|
if (ret) |
|
goto out_unlock; |
|
/* |
|
* This explicit cast to (s16) is necessary as the measurement |
|
* is done in 2's complement with positive and negative values. |
|
* The follwing assignment to *val will then convert the signed |
|
* s16 value to a signed int value. |
|
*/ |
|
*val = (s16)le16_to_cpu(hw_values[address]); |
|
out_unlock: |
|
mutex_unlock(&ak8974->lock); |
|
pm_runtime_mark_last_busy(&ak8974->i2c->dev); |
|
pm_runtime_put_autosuspend(&ak8974->i2c->dev); |
|
|
|
return ret; |
|
} |
|
|
|
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); |
|
int ret; |
|
|
|
switch (mask) { |
|
case IIO_CHAN_INFO_RAW: |
|
if (chan->address > 2) { |
|
dev_err(&ak8974->i2c->dev, "faulty channel address\n"); |
|
return -EIO; |
|
} |
|
ret = ak8974_measure_channel(ak8974, chan->address, val); |
|
if (ret) |
|
return ret; |
|
return IIO_VAL_INT; |
|
case IIO_CHAN_INFO_SCALE: |
|
switch (ak8974->variant) { |
|
case AK8974_WHOAMI_VALUE_AMI306: |
|
case AK8974_WHOAMI_VALUE_AMI305: |
|
/* |
|
* The datasheet for AMI305 and AMI306, page 6 |
|
* specifies the range of the sensor to be |
|
* +/- 12 Gauss. |
|
*/ |
|
*val = 12; |
|
/* |
|
* 12 bits are used, +/- 2^11 |
|
* [ -2048 .. 2047 ] (manual page 20) |
|
* [ 0xf800 .. 0x07ff ] |
|
*/ |
|
*val2 = 11; |
|
return IIO_VAL_FRACTIONAL_LOG2; |
|
case AK8974_WHOAMI_VALUE_HSCDTD008A: |
|
/* |
|
* The datasheet for HSCDTF008A, page 3 specifies the |
|
* range of the sensor as +/- 2.4 mT per axis, which |
|
* corresponds to +/- 2400 uT = +/- 24 Gauss. |
|
*/ |
|
*val = 24; |
|
/* |
|
* 15 bits are used (set up in CTRL4), +/- 2^14 |
|
* [ -16384 .. 16383 ] (manual page 24) |
|
* [ 0xc000 .. 0x3fff ] |
|
*/ |
|
*val2 = 14; |
|
return IIO_VAL_FRACTIONAL_LOG2; |
|
default: |
|
/* GUESSING +/- 12 Gauss */ |
|
*val = 12; |
|
/* GUESSING 12 bits ADC +/- 2^11 */ |
|
*val2 = 11; |
|
return IIO_VAL_FRACTIONAL_LOG2; |
|
} |
|
break; |
|
default: |
|
/* Unknown request */ |
|
break; |
|
} |
|
|
|
return -EINVAL; |
|
} |
|
|
|
static void ak8974_fill_buffer(struct iio_dev *indio_dev) |
|
{ |
|
struct ak8974 *ak8974 = iio_priv(indio_dev); |
|
int ret; |
|
|
|
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, ak8974->scan.channels); |
|
if (ret) { |
|
dev_err(&ak8974->i2c->dev, "error getting measures\n"); |
|
goto out_unlock; |
|
} |
|
|
|
iio_push_to_buffers_with_timestamp(indio_dev, &ak8974->scan, |
|
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, bits) \ |
|
{ \ |
|
.type = IIO_MAGN, \ |
|
.modified = 1, \ |
|
.channel2 = IIO_MOD_##axis, \ |
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ |
|
BIT(IIO_CHAN_INFO_SCALE), \ |
|
.ext_info = ak8974_ext_info, \ |
|
.address = index, \ |
|
.scan_index = index, \ |
|
.scan_type = { \ |
|
.sign = 's', \ |
|
.realbits = bits, \ |
|
.storagebits = 16, \ |
|
.endianness = IIO_LE \ |
|
}, \ |
|
} |
|
|
|
/* |
|
* We have no datasheet for the AK8974 but we guess that its |
|
* ADC is 12 bits. The AMI305 and AMI306 certainly has 12bit |
|
* ADC. |
|
*/ |
|
static const struct iio_chan_spec ak8974_12_bits_channels[] = { |
|
AK8974_AXIS_CHANNEL(X, 0, 12), |
|
AK8974_AXIS_CHANNEL(Y, 1, 12), |
|
AK8974_AXIS_CHANNEL(Z, 2, 12), |
|
IIO_CHAN_SOFT_TIMESTAMP(3), |
|
}; |
|
|
|
/* |
|
* The HSCDTD008A has 15 bits resolution the way we set it up |
|
* in CTRL4. |
|
*/ |
|
static const struct iio_chan_spec ak8974_15_bits_channels[] = { |
|
AK8974_AXIS_CHANNEL(X, 0, 15), |
|
AK8974_AXIS_CHANNEL(Y, 1, 15), |
|
AK8974_AXIS_CHANNEL(Z, 2, 15), |
|
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: |
|
return true; |
|
case AK8974_PRESET: |
|
case AK8974_PRESET + 1: |
|
return ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A; |
|
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: |
|
return ak8974->variant == AK8974_WHOAMI_VALUE_AK8974 || |
|
ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A; |
|
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 = 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) |
|
return dev_err_probe(&i2c->dev, ret, "cannot get regulators\n"); |
|
|
|
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"); |
|
pm_runtime_put_noidle(&i2c->dev); |
|
pm_runtime_disable(&i2c->dev); |
|
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 disable_pm; |
|
} |
|
|
|
ret = ak8974_detect(ak8974); |
|
if (ret) { |
|
dev_err(&i2c->dev, "neither AK8974 nor AMI30x found\n"); |
|
goto disable_pm; |
|
} |
|
|
|
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 disable_pm; |
|
} |
|
|
|
switch (ak8974->variant) { |
|
case AK8974_WHOAMI_VALUE_AMI306: |
|
case AK8974_WHOAMI_VALUE_AMI305: |
|
indio_dev->channels = ak8974_12_bits_channels; |
|
indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels); |
|
break; |
|
case AK8974_WHOAMI_VALUE_HSCDTD008A: |
|
indio_dev->channels = ak8974_15_bits_channels; |
|
indio_dev->num_channels = ARRAY_SIZE(ak8974_15_bits_channels); |
|
break; |
|
default: |
|
indio_dev->channels = ak8974_12_bits_channels; |
|
indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels); |
|
break; |
|
} |
|
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; |
|
} |
|
|
|
pm_runtime_set_autosuspend_delay(&i2c->dev, |
|
AK8974_AUTOSUSPEND_DELAY); |
|
pm_runtime_use_autosuspend(&i2c->dev); |
|
pm_runtime_put(&i2c->dev); |
|
|
|
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); |
|
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 }, |
|
{"hscdtd008a", 0 }, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(i2c, ak8974_id); |
|
|
|
static const struct of_device_id ak8974_of_match[] = { |
|
{ .compatible = "asahi-kasei,ak8974", }, |
|
{ .compatible = "alps,hscdtd008a", }, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(of, ak8974_of_match); |
|
|
|
static struct i2c_driver ak8974_driver = { |
|
.driver = { |
|
.name = "ak8974", |
|
.pm = &ak8974_dev_pm_ops, |
|
.of_match_table = 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"); |
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MODULE_LICENSE("GPL v2");
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