1123 строки
27 KiB
C
1123 строки
27 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* A sensor driver for the magnetometer AK8975.
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*
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* Magnetic compass sensor driver for monitoring magnetic flux information.
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*
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* Copyright (c) 2010, NVIDIA Corporation.
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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/slab.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.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/gpio/consumer.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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* Register definitions, as well as various shifts and masks to get at the
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* individual fields of the registers.
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*/
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#define AK8975_REG_WIA 0x00
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#define AK8975_DEVICE_ID 0x48
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#define AK8975_REG_INFO 0x01
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#define AK8975_REG_ST1 0x02
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#define AK8975_REG_ST1_DRDY_SHIFT 0
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#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT)
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#define AK8975_REG_HXL 0x03
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#define AK8975_REG_HXH 0x04
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#define AK8975_REG_HYL 0x05
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#define AK8975_REG_HYH 0x06
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#define AK8975_REG_HZL 0x07
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#define AK8975_REG_HZH 0x08
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#define AK8975_REG_ST2 0x09
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#define AK8975_REG_ST2_DERR_SHIFT 2
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#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT)
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#define AK8975_REG_ST2_HOFL_SHIFT 3
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#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT)
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#define AK8975_REG_CNTL 0x0A
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#define AK8975_REG_CNTL_MODE_SHIFT 0
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#define AK8975_REG_CNTL_MODE_MASK (0xF << AK8975_REG_CNTL_MODE_SHIFT)
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#define AK8975_REG_CNTL_MODE_POWER_DOWN 0x00
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#define AK8975_REG_CNTL_MODE_ONCE 0x01
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#define AK8975_REG_CNTL_MODE_SELF_TEST 0x08
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#define AK8975_REG_CNTL_MODE_FUSE_ROM 0x0F
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#define AK8975_REG_RSVC 0x0B
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#define AK8975_REG_ASTC 0x0C
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#define AK8975_REG_TS1 0x0D
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#define AK8975_REG_TS2 0x0E
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#define AK8975_REG_I2CDIS 0x0F
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#define AK8975_REG_ASAX 0x10
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#define AK8975_REG_ASAY 0x11
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#define AK8975_REG_ASAZ 0x12
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#define AK8975_MAX_REGS AK8975_REG_ASAZ
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/*
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* AK09912 Register definitions
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*/
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#define AK09912_REG_WIA1 0x00
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#define AK09912_REG_WIA2 0x01
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#define AK09916_DEVICE_ID 0x09
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#define AK09912_DEVICE_ID 0x04
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#define AK09911_DEVICE_ID 0x05
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#define AK09911_REG_INFO1 0x02
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#define AK09911_REG_INFO2 0x03
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#define AK09912_REG_ST1 0x10
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#define AK09912_REG_ST1_DRDY_SHIFT 0
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#define AK09912_REG_ST1_DRDY_MASK (1 << AK09912_REG_ST1_DRDY_SHIFT)
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#define AK09912_REG_HXL 0x11
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#define AK09912_REG_HXH 0x12
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#define AK09912_REG_HYL 0x13
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#define AK09912_REG_HYH 0x14
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#define AK09912_REG_HZL 0x15
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#define AK09912_REG_HZH 0x16
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#define AK09912_REG_TMPS 0x17
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#define AK09912_REG_ST2 0x18
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#define AK09912_REG_ST2_HOFL_SHIFT 3
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#define AK09912_REG_ST2_HOFL_MASK (1 << AK09912_REG_ST2_HOFL_SHIFT)
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#define AK09912_REG_CNTL1 0x30
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#define AK09912_REG_CNTL2 0x31
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#define AK09912_REG_CNTL_MODE_POWER_DOWN 0x00
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#define AK09912_REG_CNTL_MODE_ONCE 0x01
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#define AK09912_REG_CNTL_MODE_SELF_TEST 0x10
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#define AK09912_REG_CNTL_MODE_FUSE_ROM 0x1F
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#define AK09912_REG_CNTL2_MODE_SHIFT 0
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#define AK09912_REG_CNTL2_MODE_MASK (0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
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#define AK09912_REG_CNTL3 0x32
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#define AK09912_REG_TS1 0x33
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#define AK09912_REG_TS2 0x34
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#define AK09912_REG_TS3 0x35
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#define AK09912_REG_I2CDIS 0x36
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#define AK09912_REG_TS4 0x37
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#define AK09912_REG_ASAX 0x60
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#define AK09912_REG_ASAY 0x61
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#define AK09912_REG_ASAZ 0x62
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#define AK09912_MAX_REGS AK09912_REG_ASAZ
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/*
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* Miscellaneous values.
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*/
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#define AK8975_MAX_CONVERSION_TIMEOUT 500
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#define AK8975_CONVERSION_DONE_POLL_TIME 10
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#define AK8975_DATA_READY_TIMEOUT ((100*HZ)/1000)
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/*
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* Precalculate scale factor (in Gauss units) for each axis and
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* store in the device data.
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*
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* This scale factor is axis-dependent, and is derived from 3 calibration
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* factors ASA(x), ASA(y), and ASA(z).
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*
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* These ASA values are read from the sensor device at start of day, and
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* cached in the device context struct.
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*
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* Adjusting the flux value with the sensitivity adjustment value should be
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* done via the following formula:
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*
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* Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
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* where H is the raw value, ASA is the sensitivity adjustment, and Hadj
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* is the resultant adjusted value.
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*
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* We reduce the formula to:
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*
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* Hadj = H * (ASA + 128) / 256
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*
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* H is in the range of -4096 to 4095. The magnetometer has a range of
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* +-1229uT. To go from the raw value to uT is:
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*
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* HuT = H * 1229/4096, or roughly, 3/10.
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*
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* Since 1uT = 0.01 gauss, our final scale factor becomes:
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*
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* Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
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* Hadj = H * ((ASA + 128) * 0.003) / 256
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*
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* Since ASA doesn't change, we cache the resultant scale factor into the
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* device context in ak8975_setup().
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*
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* Given we use IIO_VAL_INT_PLUS_MICRO bit when displaying the scale, we
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* multiply the stored scale value by 1e6.
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*/
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static long ak8975_raw_to_gauss(u16 data)
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{
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return (((long)data + 128) * 3000) / 256;
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}
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/*
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* For AK8963 and AK09911, same calculation, but the device is less sensitive:
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*
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* H is in the range of +-8190. The magnetometer has a range of
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* +-4912uT. To go from the raw value to uT is:
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*
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* HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
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*/
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static long ak8963_09911_raw_to_gauss(u16 data)
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{
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return (((long)data + 128) * 6000) / 256;
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}
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/*
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* For AK09912, same calculation, except the device is more sensitive:
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*
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* H is in the range of -32752 to 32752. The magnetometer has a range of
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* +-4912uT. To go from the raw value to uT is:
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*
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* HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
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*/
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static long ak09912_raw_to_gauss(u16 data)
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{
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return (((long)data + 128) * 1500) / 256;
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}
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/* Compatible Asahi Kasei Compass parts */
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enum asahi_compass_chipset {
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AKXXXX = 0,
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AK8975,
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AK8963,
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AK09911,
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AK09912,
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AK09916,
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};
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enum ak_ctrl_reg_addr {
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ST1,
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ST2,
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CNTL,
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ASA_BASE,
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MAX_REGS,
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REGS_END,
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};
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enum ak_ctrl_reg_mask {
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ST1_DRDY,
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ST2_HOFL,
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ST2_DERR,
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CNTL_MODE,
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MASK_END,
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};
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enum ak_ctrl_mode {
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POWER_DOWN,
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MODE_ONCE,
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SELF_TEST,
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FUSE_ROM,
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MODE_END,
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};
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struct ak_def {
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enum asahi_compass_chipset type;
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long (*raw_to_gauss)(u16 data);
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u16 range;
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u8 ctrl_regs[REGS_END];
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u8 ctrl_masks[MASK_END];
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u8 ctrl_modes[MODE_END];
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u8 data_regs[3];
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};
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static const struct ak_def ak_def_array[] = {
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{
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.type = AK8975,
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.raw_to_gauss = ak8975_raw_to_gauss,
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.range = 4096,
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.ctrl_regs = {
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AK8975_REG_ST1,
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AK8975_REG_ST2,
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AK8975_REG_CNTL,
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AK8975_REG_ASAX,
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AK8975_MAX_REGS},
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.ctrl_masks = {
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AK8975_REG_ST1_DRDY_MASK,
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AK8975_REG_ST2_HOFL_MASK,
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AK8975_REG_ST2_DERR_MASK,
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AK8975_REG_CNTL_MODE_MASK},
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.ctrl_modes = {
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AK8975_REG_CNTL_MODE_POWER_DOWN,
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AK8975_REG_CNTL_MODE_ONCE,
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AK8975_REG_CNTL_MODE_SELF_TEST,
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AK8975_REG_CNTL_MODE_FUSE_ROM},
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.data_regs = {
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AK8975_REG_HXL,
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AK8975_REG_HYL,
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AK8975_REG_HZL},
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},
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{
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.type = AK8963,
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.raw_to_gauss = ak8963_09911_raw_to_gauss,
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.range = 8190,
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.ctrl_regs = {
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AK8975_REG_ST1,
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AK8975_REG_ST2,
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AK8975_REG_CNTL,
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AK8975_REG_ASAX,
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AK8975_MAX_REGS},
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.ctrl_masks = {
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AK8975_REG_ST1_DRDY_MASK,
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AK8975_REG_ST2_HOFL_MASK,
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0,
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AK8975_REG_CNTL_MODE_MASK},
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.ctrl_modes = {
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AK8975_REG_CNTL_MODE_POWER_DOWN,
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AK8975_REG_CNTL_MODE_ONCE,
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AK8975_REG_CNTL_MODE_SELF_TEST,
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AK8975_REG_CNTL_MODE_FUSE_ROM},
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.data_regs = {
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AK8975_REG_HXL,
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AK8975_REG_HYL,
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AK8975_REG_HZL},
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},
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{
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.type = AK09911,
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.raw_to_gauss = ak8963_09911_raw_to_gauss,
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.range = 8192,
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.ctrl_regs = {
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AK09912_REG_ST1,
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AK09912_REG_ST2,
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AK09912_REG_CNTL2,
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AK09912_REG_ASAX,
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AK09912_MAX_REGS},
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.ctrl_masks = {
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AK09912_REG_ST1_DRDY_MASK,
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AK09912_REG_ST2_HOFL_MASK,
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0,
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AK09912_REG_CNTL2_MODE_MASK},
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.ctrl_modes = {
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AK09912_REG_CNTL_MODE_POWER_DOWN,
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AK09912_REG_CNTL_MODE_ONCE,
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AK09912_REG_CNTL_MODE_SELF_TEST,
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AK09912_REG_CNTL_MODE_FUSE_ROM},
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.data_regs = {
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AK09912_REG_HXL,
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AK09912_REG_HYL,
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AK09912_REG_HZL},
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},
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{
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.type = AK09912,
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.raw_to_gauss = ak09912_raw_to_gauss,
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.range = 32752,
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.ctrl_regs = {
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AK09912_REG_ST1,
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AK09912_REG_ST2,
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AK09912_REG_CNTL2,
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AK09912_REG_ASAX,
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AK09912_MAX_REGS},
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.ctrl_masks = {
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AK09912_REG_ST1_DRDY_MASK,
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AK09912_REG_ST2_HOFL_MASK,
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0,
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AK09912_REG_CNTL2_MODE_MASK},
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.ctrl_modes = {
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AK09912_REG_CNTL_MODE_POWER_DOWN,
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AK09912_REG_CNTL_MODE_ONCE,
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AK09912_REG_CNTL_MODE_SELF_TEST,
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AK09912_REG_CNTL_MODE_FUSE_ROM},
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.data_regs = {
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AK09912_REG_HXL,
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AK09912_REG_HYL,
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AK09912_REG_HZL},
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},
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{
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.type = AK09916,
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.raw_to_gauss = ak09912_raw_to_gauss,
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.range = 32752,
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.ctrl_regs = {
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AK09912_REG_ST1,
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AK09912_REG_ST2,
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AK09912_REG_CNTL2,
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AK09912_REG_ASAX,
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AK09912_MAX_REGS},
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.ctrl_masks = {
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AK09912_REG_ST1_DRDY_MASK,
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AK09912_REG_ST2_HOFL_MASK,
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0,
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AK09912_REG_CNTL2_MODE_MASK},
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.ctrl_modes = {
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AK09912_REG_CNTL_MODE_POWER_DOWN,
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AK09912_REG_CNTL_MODE_ONCE,
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AK09912_REG_CNTL_MODE_SELF_TEST,
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AK09912_REG_CNTL_MODE_FUSE_ROM},
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.data_regs = {
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AK09912_REG_HXL,
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AK09912_REG_HYL,
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AK09912_REG_HZL},
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}
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};
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/*
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* Per-instance context data for the device.
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*/
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struct ak8975_data {
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struct i2c_client *client;
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const struct ak_def *def;
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struct mutex lock;
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u8 asa[3];
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long raw_to_gauss[3];
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struct gpio_desc *eoc_gpiod;
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struct gpio_desc *reset_gpiod;
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int eoc_irq;
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wait_queue_head_t data_ready_queue;
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unsigned long flags;
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u8 cntl_cache;
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struct iio_mount_matrix orientation;
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struct regulator *vdd;
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struct regulator *vid;
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/* Ensure natural alignment of timestamp */
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struct {
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s16 channels[3];
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s64 ts __aligned(8);
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} scan;
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};
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/* Enable attached power regulator if any. */
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static int ak8975_power_on(const struct ak8975_data *data)
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{
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int ret;
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ret = regulator_enable(data->vdd);
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if (ret) {
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dev_warn(&data->client->dev,
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"Failed to enable specified Vdd supply\n");
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return ret;
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}
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ret = regulator_enable(data->vid);
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if (ret) {
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dev_warn(&data->client->dev,
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"Failed to enable specified Vid supply\n");
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return ret;
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}
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gpiod_set_value_cansleep(data->reset_gpiod, 0);
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/*
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* According to the datasheet the power supply rise time is 200us
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* and the minimum wait time before mode setting is 100us, in
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* total 300us. Add some margin and say minimum 500us here.
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*/
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usleep_range(500, 1000);
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return 0;
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}
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/* Disable attached power regulator if any. */
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static void ak8975_power_off(const struct ak8975_data *data)
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{
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gpiod_set_value_cansleep(data->reset_gpiod, 1);
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regulator_disable(data->vid);
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regulator_disable(data->vdd);
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}
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/*
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* Return 0 if the i2c device is the one we expect.
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* return a negative error number otherwise
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*/
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static int ak8975_who_i_am(struct i2c_client *client,
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enum asahi_compass_chipset type)
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{
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u8 wia_val[2];
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int ret;
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/*
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* Signature for each device:
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* Device | WIA1 | WIA2
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* AK09916 | DEVICE_ID_| AK09916_DEVICE_ID
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* AK09912 | DEVICE_ID | AK09912_DEVICE_ID
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* AK09911 | DEVICE_ID | AK09911_DEVICE_ID
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* AK8975 | DEVICE_ID | NA
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* AK8963 | DEVICE_ID | NA
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*/
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ret = i2c_smbus_read_i2c_block_data_or_emulated(
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client, AK09912_REG_WIA1, 2, wia_val);
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if (ret < 0) {
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dev_err(&client->dev, "Error reading WIA\n");
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return ret;
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}
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if (wia_val[0] != AK8975_DEVICE_ID)
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return -ENODEV;
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switch (type) {
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case AK8975:
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case AK8963:
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return 0;
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case AK09911:
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if (wia_val[1] == AK09911_DEVICE_ID)
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return 0;
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break;
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case AK09912:
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if (wia_val[1] == AK09912_DEVICE_ID)
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return 0;
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break;
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case AK09916:
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if (wia_val[1] == AK09916_DEVICE_ID)
|
|
return 0;
|
|
break;
|
|
default:
|
|
dev_err(&client->dev, "Type %d unknown\n", type);
|
|
}
|
|
return -ENODEV;
|
|
}
|
|
|
|
/*
|
|
* Helper function to write to CNTL register.
|
|
*/
|
|
static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
|
|
{
|
|
u8 regval;
|
|
int ret;
|
|
|
|
regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) |
|
|
data->def->ctrl_modes[mode];
|
|
ret = i2c_smbus_write_byte_data(data->client,
|
|
data->def->ctrl_regs[CNTL], regval);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
data->cntl_cache = regval;
|
|
/* After mode change wait atleast 100us */
|
|
usleep_range(100, 500);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Handle data ready irq
|
|
*/
|
|
static irqreturn_t ak8975_irq_handler(int irq, void *data)
|
|
{
|
|
struct ak8975_data *ak8975 = data;
|
|
|
|
set_bit(0, &ak8975->flags);
|
|
wake_up(&ak8975->data_ready_queue);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* Install data ready interrupt handler
|
|
*/
|
|
static int ak8975_setup_irq(struct ak8975_data *data)
|
|
{
|
|
struct i2c_client *client = data->client;
|
|
int rc;
|
|
int irq;
|
|
|
|
init_waitqueue_head(&data->data_ready_queue);
|
|
clear_bit(0, &data->flags);
|
|
if (client->irq)
|
|
irq = client->irq;
|
|
else
|
|
irq = gpiod_to_irq(data->eoc_gpiod);
|
|
|
|
rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
|
|
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
|
|
dev_name(&client->dev), data);
|
|
if (rc < 0) {
|
|
dev_err(&client->dev, "irq %d request failed: %d\n", irq, rc);
|
|
return rc;
|
|
}
|
|
|
|
data->eoc_irq = irq;
|
|
|
|
return rc;
|
|
}
|
|
|
|
|
|
/*
|
|
* Perform some start-of-day setup, including reading the asa calibration
|
|
* values and caching them.
|
|
*/
|
|
static int ak8975_setup(struct i2c_client *client)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
/* Write the fused rom access mode. */
|
|
ret = ak8975_set_mode(data, FUSE_ROM);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting fuse access mode\n");
|
|
return ret;
|
|
}
|
|
|
|
/* Get asa data and store in the device data. */
|
|
ret = i2c_smbus_read_i2c_block_data_or_emulated(
|
|
client, data->def->ctrl_regs[ASA_BASE],
|
|
3, data->asa);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Not able to read asa data\n");
|
|
return ret;
|
|
}
|
|
|
|
/* After reading fuse ROM data set power-down mode */
|
|
ret = ak8975_set_mode(data, POWER_DOWN);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting power-down mode\n");
|
|
return ret;
|
|
}
|
|
|
|
if (data->eoc_gpiod || client->irq > 0) {
|
|
ret = ak8975_setup_irq(data);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev,
|
|
"Error setting data ready interrupt\n");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
data->raw_to_gauss[0] = data->def->raw_to_gauss(data->asa[0]);
|
|
data->raw_to_gauss[1] = data->def->raw_to_gauss(data->asa[1]);
|
|
data->raw_to_gauss[2] = data->def->raw_to_gauss(data->asa[2]);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int wait_conversion_complete_gpio(struct ak8975_data *data)
|
|
{
|
|
struct i2c_client *client = data->client;
|
|
u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT;
|
|
int ret;
|
|
|
|
/* Wait for the conversion to complete. */
|
|
while (timeout_ms) {
|
|
msleep(AK8975_CONVERSION_DONE_POLL_TIME);
|
|
if (gpiod_get_value(data->eoc_gpiod))
|
|
break;
|
|
timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
|
|
}
|
|
if (!timeout_ms) {
|
|
dev_err(&client->dev, "Conversion timeout happened\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST1]);
|
|
if (ret < 0)
|
|
dev_err(&client->dev, "Error in reading ST1\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wait_conversion_complete_polled(struct ak8975_data *data)
|
|
{
|
|
struct i2c_client *client = data->client;
|
|
u8 read_status;
|
|
u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT;
|
|
int ret;
|
|
|
|
/* Wait for the conversion to complete. */
|
|
while (timeout_ms) {
|
|
msleep(AK8975_CONVERSION_DONE_POLL_TIME);
|
|
ret = i2c_smbus_read_byte_data(client,
|
|
data->def->ctrl_regs[ST1]);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in reading ST1\n");
|
|
return ret;
|
|
}
|
|
read_status = ret;
|
|
if (read_status)
|
|
break;
|
|
timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
|
|
}
|
|
if (!timeout_ms) {
|
|
dev_err(&client->dev, "Conversion timeout happened\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return read_status;
|
|
}
|
|
|
|
/* Returns 0 if the end of conversion interrupt occured or -ETIME otherwise */
|
|
static int wait_conversion_complete_interrupt(struct ak8975_data *data)
|
|
{
|
|
int ret;
|
|
|
|
ret = wait_event_timeout(data->data_ready_queue,
|
|
test_bit(0, &data->flags),
|
|
AK8975_DATA_READY_TIMEOUT);
|
|
clear_bit(0, &data->flags);
|
|
|
|
return ret > 0 ? 0 : -ETIME;
|
|
}
|
|
|
|
static int ak8975_start_read_axis(struct ak8975_data *data,
|
|
const struct i2c_client *client)
|
|
{
|
|
/* Set up the device for taking a sample. */
|
|
int ret = ak8975_set_mode(data, MODE_ONCE);
|
|
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting operating mode\n");
|
|
return ret;
|
|
}
|
|
|
|
/* Wait for the conversion to complete. */
|
|
if (data->eoc_irq)
|
|
ret = wait_conversion_complete_interrupt(data);
|
|
else if (data->eoc_gpiod)
|
|
ret = wait_conversion_complete_gpio(data);
|
|
else
|
|
ret = wait_conversion_complete_polled(data);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* This will be executed only for non-interrupt based waiting case */
|
|
if (ret & data->def->ctrl_masks[ST1_DRDY]) {
|
|
ret = i2c_smbus_read_byte_data(client,
|
|
data->def->ctrl_regs[ST2]);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in reading ST2\n");
|
|
return ret;
|
|
}
|
|
if (ret & (data->def->ctrl_masks[ST2_DERR] |
|
|
data->def->ctrl_masks[ST2_HOFL])) {
|
|
dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Retrieve raw flux value for one of the x, y, or z axis. */
|
|
static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
|
|
{
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
const struct i2c_client *client = data->client;
|
|
const struct ak_def *def = data->def;
|
|
__le16 rval;
|
|
u16 buff;
|
|
int ret;
|
|
|
|
pm_runtime_get_sync(&data->client->dev);
|
|
|
|
mutex_lock(&data->lock);
|
|
|
|
ret = ak8975_start_read_axis(data, client);
|
|
if (ret)
|
|
goto exit;
|
|
|
|
ret = i2c_smbus_read_i2c_block_data_or_emulated(
|
|
client, def->data_regs[index],
|
|
sizeof(rval), (u8*)&rval);
|
|
if (ret < 0)
|
|
goto exit;
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
pm_runtime_mark_last_busy(&data->client->dev);
|
|
pm_runtime_put_autosuspend(&data->client->dev);
|
|
|
|
/* Swap bytes and convert to valid range. */
|
|
buff = le16_to_cpu(rval);
|
|
*val = clamp_t(s16, buff, -def->range, def->range);
|
|
return IIO_VAL_INT;
|
|
|
|
exit:
|
|
mutex_unlock(&data->lock);
|
|
dev_err(&client->dev, "Error in reading axis\n");
|
|
return ret;
|
|
}
|
|
|
|
static int ak8975_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2,
|
|
long mask)
|
|
{
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_RAW:
|
|
return ak8975_read_axis(indio_dev, chan->address, val);
|
|
case IIO_CHAN_INFO_SCALE:
|
|
*val = 0;
|
|
*val2 = data->raw_to_gauss[chan->address];
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static const struct iio_mount_matrix *
|
|
ak8975_get_mount_matrix(const struct iio_dev *indio_dev,
|
|
const struct iio_chan_spec *chan)
|
|
{
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
|
|
return &data->orientation;
|
|
}
|
|
|
|
static const struct iio_chan_spec_ext_info ak8975_ext_info[] = {
|
|
IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8975_get_mount_matrix),
|
|
{ }
|
|
};
|
|
|
|
#define AK8975_CHANNEL(axis, index) \
|
|
{ \
|
|
.type = IIO_MAGN, \
|
|
.modified = 1, \
|
|
.channel2 = IIO_MOD_##axis, \
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
|
|
BIT(IIO_CHAN_INFO_SCALE), \
|
|
.address = index, \
|
|
.scan_index = index, \
|
|
.scan_type = { \
|
|
.sign = 's', \
|
|
.realbits = 16, \
|
|
.storagebits = 16, \
|
|
.endianness = IIO_CPU \
|
|
}, \
|
|
.ext_info = ak8975_ext_info, \
|
|
}
|
|
|
|
static const struct iio_chan_spec ak8975_channels[] = {
|
|
AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
|
|
IIO_CHAN_SOFT_TIMESTAMP(3),
|
|
};
|
|
|
|
static const unsigned long ak8975_scan_masks[] = { 0x7, 0 };
|
|
|
|
static const struct iio_info ak8975_info = {
|
|
.read_raw = &ak8975_read_raw,
|
|
};
|
|
|
|
static const struct acpi_device_id ak_acpi_match[] = {
|
|
{"AK8975", AK8975},
|
|
{"AK8963", AK8963},
|
|
{"INVN6500", AK8963},
|
|
{"AK009911", AK09911},
|
|
{"AK09911", AK09911},
|
|
{"AKM9911", AK09911},
|
|
{"AK09912", AK09912},
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
|
|
|
|
static void ak8975_fill_buffer(struct iio_dev *indio_dev)
|
|
{
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
const struct i2c_client *client = data->client;
|
|
const struct ak_def *def = data->def;
|
|
int ret;
|
|
__le16 fval[3];
|
|
|
|
mutex_lock(&data->lock);
|
|
|
|
ret = ak8975_start_read_axis(data, client);
|
|
if (ret)
|
|
goto unlock;
|
|
|
|
/*
|
|
* For each axis, read the flux value from the appropriate register
|
|
* (the register is specified in the iio device attributes).
|
|
*/
|
|
ret = i2c_smbus_read_i2c_block_data_or_emulated(client,
|
|
def->data_regs[0],
|
|
3 * sizeof(fval[0]),
|
|
(u8 *)fval);
|
|
if (ret < 0)
|
|
goto unlock;
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
/* Clamp to valid range. */
|
|
data->scan.channels[0] = clamp_t(s16, le16_to_cpu(fval[0]), -def->range, def->range);
|
|
data->scan.channels[1] = clamp_t(s16, le16_to_cpu(fval[1]), -def->range, def->range);
|
|
data->scan.channels[2] = clamp_t(s16, le16_to_cpu(fval[2]), -def->range, def->range);
|
|
|
|
iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
|
|
iio_get_time_ns(indio_dev));
|
|
|
|
return;
|
|
|
|
unlock:
|
|
mutex_unlock(&data->lock);
|
|
dev_err(&client->dev, "Error in reading axes block\n");
|
|
}
|
|
|
|
static irqreturn_t ak8975_handle_trigger(int irq, void *p)
|
|
{
|
|
const struct iio_poll_func *pf = p;
|
|
struct iio_dev *indio_dev = pf->indio_dev;
|
|
|
|
ak8975_fill_buffer(indio_dev);
|
|
iio_trigger_notify_done(indio_dev->trig);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int ak8975_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct ak8975_data *data;
|
|
struct iio_dev *indio_dev;
|
|
struct gpio_desc *eoc_gpiod;
|
|
struct gpio_desc *reset_gpiod;
|
|
const void *match;
|
|
unsigned int i;
|
|
int err;
|
|
enum asahi_compass_chipset chipset;
|
|
const char *name = NULL;
|
|
|
|
/*
|
|
* Grab and set up the supplied GPIO.
|
|
* We may not have a GPIO based IRQ to scan, that is fine, we will
|
|
* poll if so.
|
|
*/
|
|
eoc_gpiod = devm_gpiod_get_optional(&client->dev, NULL, GPIOD_IN);
|
|
if (IS_ERR(eoc_gpiod))
|
|
return PTR_ERR(eoc_gpiod);
|
|
if (eoc_gpiod)
|
|
gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
|
|
|
|
/*
|
|
* According to AK09911 datasheet, if reset GPIO is provided then
|
|
* deassert reset on ak8975_power_on() and assert reset on
|
|
* ak8975_power_off().
|
|
*/
|
|
reset_gpiod = devm_gpiod_get_optional(&client->dev,
|
|
"reset", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(reset_gpiod))
|
|
return PTR_ERR(reset_gpiod);
|
|
|
|
/* Register with IIO */
|
|
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
|
|
if (indio_dev == NULL)
|
|
return -ENOMEM;
|
|
|
|
data = iio_priv(indio_dev);
|
|
i2c_set_clientdata(client, indio_dev);
|
|
|
|
data->client = client;
|
|
data->eoc_gpiod = eoc_gpiod;
|
|
data->reset_gpiod = reset_gpiod;
|
|
data->eoc_irq = 0;
|
|
|
|
err = iio_read_mount_matrix(&client->dev, &data->orientation);
|
|
if (err)
|
|
return err;
|
|
|
|
/* id will be NULL when enumerated via ACPI */
|
|
match = device_get_match_data(&client->dev);
|
|
if (match) {
|
|
chipset = (uintptr_t)match;
|
|
name = dev_name(&client->dev);
|
|
} else if (id) {
|
|
chipset = (enum asahi_compass_chipset)(id->driver_data);
|
|
name = id->name;
|
|
} else
|
|
return -ENOSYS;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(ak_def_array); i++)
|
|
if (ak_def_array[i].type == chipset)
|
|
break;
|
|
|
|
if (i == ARRAY_SIZE(ak_def_array)) {
|
|
dev_err(&client->dev, "AKM device type unsupported: %d\n",
|
|
chipset);
|
|
return -ENODEV;
|
|
}
|
|
|
|
data->def = &ak_def_array[i];
|
|
|
|
/* Fetch the regulators */
|
|
data->vdd = devm_regulator_get(&client->dev, "vdd");
|
|
if (IS_ERR(data->vdd))
|
|
return PTR_ERR(data->vdd);
|
|
data->vid = devm_regulator_get(&client->dev, "vid");
|
|
if (IS_ERR(data->vid))
|
|
return PTR_ERR(data->vid);
|
|
|
|
err = ak8975_power_on(data);
|
|
if (err)
|
|
return err;
|
|
|
|
err = ak8975_who_i_am(client, data->def->type);
|
|
if (err < 0) {
|
|
dev_err(&client->dev, "Unexpected device\n");
|
|
goto power_off;
|
|
}
|
|
dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
|
|
|
|
/* Perform some basic start-of-day setup of the device. */
|
|
err = ak8975_setup(client);
|
|
if (err < 0) {
|
|
dev_err(&client->dev, "%s initialization fails\n", name);
|
|
goto power_off;
|
|
}
|
|
|
|
mutex_init(&data->lock);
|
|
indio_dev->channels = ak8975_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
|
|
indio_dev->info = &ak8975_info;
|
|
indio_dev->available_scan_masks = ak8975_scan_masks;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->name = name;
|
|
|
|
err = iio_triggered_buffer_setup(indio_dev, NULL, ak8975_handle_trigger,
|
|
NULL);
|
|
if (err) {
|
|
dev_err(&client->dev, "triggered buffer setup failed\n");
|
|
goto power_off;
|
|
}
|
|
|
|
err = iio_device_register(indio_dev);
|
|
if (err) {
|
|
dev_err(&client->dev, "device register failed\n");
|
|
goto cleanup_buffer;
|
|
}
|
|
|
|
/* Enable runtime PM */
|
|
pm_runtime_get_noresume(&client->dev);
|
|
pm_runtime_set_active(&client->dev);
|
|
pm_runtime_enable(&client->dev);
|
|
/*
|
|
* The device comes online in 500us, so add two orders of magnitude
|
|
* of delay before autosuspending: 50 ms.
|
|
*/
|
|
pm_runtime_set_autosuspend_delay(&client->dev, 50);
|
|
pm_runtime_use_autosuspend(&client->dev);
|
|
pm_runtime_put(&client->dev);
|
|
|
|
return 0;
|
|
|
|
cleanup_buffer:
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
power_off:
|
|
ak8975_power_off(data);
|
|
return err;
|
|
}
|
|
|
|
static int ak8975_remove(struct i2c_client *client)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
|
|
pm_runtime_get_sync(&client->dev);
|
|
pm_runtime_put_noidle(&client->dev);
|
|
pm_runtime_disable(&client->dev);
|
|
iio_device_unregister(indio_dev);
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
ak8975_set_mode(data, POWER_DOWN);
|
|
ak8975_power_off(data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ak8975_runtime_suspend(struct device *dev)
|
|
{
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
/* Set the device in power down if it wasn't already */
|
|
ret = ak8975_set_mode(data, POWER_DOWN);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting power-down mode\n");
|
|
return ret;
|
|
}
|
|
/* Next cut the regulators */
|
|
ak8975_power_off(data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ak8975_runtime_resume(struct device *dev)
|
|
{
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct ak8975_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
/* Take up the regulators */
|
|
ak8975_power_on(data);
|
|
/*
|
|
* We come up in powered down mode, the reading routines will
|
|
* put us in the mode to read values later.
|
|
*/
|
|
ret = ak8975_set_mode(data, POWER_DOWN);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting power-down mode\n");
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static DEFINE_RUNTIME_DEV_PM_OPS(ak8975_dev_pm_ops, ak8975_runtime_suspend,
|
|
ak8975_runtime_resume, NULL);
|
|
|
|
static const struct i2c_device_id ak8975_id[] = {
|
|
{"ak8975", AK8975},
|
|
{"ak8963", AK8963},
|
|
{"AK8963", AK8963},
|
|
{"ak09911", AK09911},
|
|
{"ak09912", AK09912},
|
|
{"ak09916", AK09916},
|
|
{}
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(i2c, ak8975_id);
|
|
|
|
static const struct of_device_id ak8975_of_match[] = {
|
|
{ .compatible = "asahi-kasei,ak8975", },
|
|
{ .compatible = "ak8975", },
|
|
{ .compatible = "asahi-kasei,ak8963", },
|
|
{ .compatible = "ak8963", },
|
|
{ .compatible = "asahi-kasei,ak09911", },
|
|
{ .compatible = "ak09911", },
|
|
{ .compatible = "asahi-kasei,ak09912", },
|
|
{ .compatible = "ak09912", },
|
|
{ .compatible = "asahi-kasei,ak09916", },
|
|
{ .compatible = "ak09916", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ak8975_of_match);
|
|
|
|
static struct i2c_driver ak8975_driver = {
|
|
.driver = {
|
|
.name = "ak8975",
|
|
.pm = pm_ptr(&ak8975_dev_pm_ops),
|
|
.of_match_table = ak8975_of_match,
|
|
.acpi_match_table = ak_acpi_match,
|
|
},
|
|
.probe = ak8975_probe,
|
|
.remove = ak8975_remove,
|
|
.id_table = ak8975_id,
|
|
};
|
|
module_i2c_driver(ak8975_driver);
|
|
|
|
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
|
|
MODULE_DESCRIPTION("AK8975 magnetometer driver");
|
|
MODULE_LICENSE("GPL");
|