851 строка
21 KiB
C
851 строка
21 KiB
C
/*
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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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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/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.h>
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#include <linux/of_gpio.h>
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#include <linux/acpi.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/sysfs.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 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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AK8975,
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AK8963,
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AK09911,
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AK09912,
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AK_MAX_TYPE
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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 struct ak_def ak_def_array[AK_MAX_TYPE] = {
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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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/*
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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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struct ak_def *def;
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struct attribute_group attrs;
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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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int eoc_gpio;
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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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};
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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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* 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(client, AK09912_REG_WIA1,
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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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default:
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dev_err(&client->dev, "Type %d unknown\n", type);
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}
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return -ENODEV;
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}
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/*
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* Helper function to write to CNTL register.
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*/
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static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
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{
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u8 regval;
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int ret;
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regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) |
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data->def->ctrl_modes[mode];
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ret = i2c_smbus_write_byte_data(data->client,
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data->def->ctrl_regs[CNTL], regval);
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if (ret < 0) {
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return ret;
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}
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data->cntl_cache = regval;
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/* After mode change wait atleast 100us */
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usleep_range(100, 500);
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return 0;
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}
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/*
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* Handle data ready irq
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*/
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static irqreturn_t ak8975_irq_handler(int irq, void *data)
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{
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struct ak8975_data *ak8975 = data;
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set_bit(0, &ak8975->flags);
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wake_up(&ak8975->data_ready_queue);
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return IRQ_HANDLED;
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}
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/*
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* Install data ready interrupt handler
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*/
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static int ak8975_setup_irq(struct ak8975_data *data)
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{
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struct i2c_client *client = data->client;
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int rc;
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int irq;
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if (client->irq)
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irq = client->irq;
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else
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irq = gpio_to_irq(data->eoc_gpio);
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rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
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IRQF_TRIGGER_RISING | IRQF_ONESHOT,
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dev_name(&client->dev), data);
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if (rc < 0) {
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dev_err(&client->dev,
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"irq %d request failed, (gpio %d): %d\n",
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irq, data->eoc_gpio, rc);
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return rc;
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}
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init_waitqueue_head(&data->data_ready_queue);
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clear_bit(0, &data->flags);
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data->eoc_irq = irq;
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return rc;
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}
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/*
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* Perform some start-of-day setup, including reading the asa calibration
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* values and caching them.
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*/
|
|
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(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_gpio > 0 || 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 (gpio_get_value(data->eoc_gpio))
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Emits the raw flux value for 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);
|
|
struct i2c_client *client = data->client;
|
|
int ret;
|
|
|
|
mutex_lock(&data->lock);
|
|
|
|
/* Set up the device for taking a sample. */
|
|
ret = ak8975_set_mode(data, MODE_ONCE);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Error in setting operating mode\n");
|
|
goto exit;
|
|
}
|
|
|
|
/* Wait for the conversion to complete. */
|
|
if (data->eoc_irq)
|
|
ret = wait_conversion_complete_interrupt(data);
|
|
else if (gpio_is_valid(data->eoc_gpio))
|
|
ret = wait_conversion_complete_gpio(data);
|
|
else
|
|
ret = wait_conversion_complete_polled(data);
|
|
if (ret < 0)
|
|
goto exit;
|
|
|
|
/* 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");
|
|
goto exit;
|
|
}
|
|
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);
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
}
|
|
|
|
/* Read the flux value from the appropriate register
|
|
(the register is specified in the iio device attributes). */
|
|
ret = i2c_smbus_read_word_data(client, data->def->data_regs[index]);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Read axis data fails\n");
|
|
goto exit;
|
|
}
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
/* Clamp to valid range. */
|
|
*val = clamp_t(s16, ret, -data->def->range, data->def->range);
|
|
return IIO_VAL_INT;
|
|
|
|
exit:
|
|
mutex_unlock(&data->lock);
|
|
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;
|
|
}
|
|
|
|
#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, \
|
|
}
|
|
|
|
static const struct iio_chan_spec ak8975_channels[] = {
|
|
AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
|
|
};
|
|
|
|
static const struct iio_info ak8975_info = {
|
|
.read_raw = &ak8975_read_raw,
|
|
.driver_module = THIS_MODULE,
|
|
};
|
|
|
|
static const struct acpi_device_id ak_acpi_match[] = {
|
|
{"AK8975", AK8975},
|
|
{"AK8963", AK8963},
|
|
{"INVN6500", AK8963},
|
|
{"AK09911", AK09911},
|
|
{"AK09912", AK09912},
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
|
|
|
|
static const char *ak8975_match_acpi_device(struct device *dev,
|
|
enum asahi_compass_chipset *chipset)
|
|
{
|
|
const struct acpi_device_id *id;
|
|
|
|
id = acpi_match_device(dev->driver->acpi_match_table, dev);
|
|
if (!id)
|
|
return NULL;
|
|
*chipset = (int)id->driver_data;
|
|
|
|
return dev_name(dev);
|
|
}
|
|
|
|
static int ak8975_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct ak8975_data *data;
|
|
struct iio_dev *indio_dev;
|
|
int eoc_gpio;
|
|
int err;
|
|
const char *name = NULL;
|
|
enum asahi_compass_chipset chipset;
|
|
|
|
/* Grab and set up the supplied GPIO. */
|
|
if (client->dev.platform_data)
|
|
eoc_gpio = *(int *)(client->dev.platform_data);
|
|
else if (client->dev.of_node)
|
|
eoc_gpio = of_get_gpio(client->dev.of_node, 0);
|
|
else
|
|
eoc_gpio = -1;
|
|
|
|
if (eoc_gpio == -EPROBE_DEFER)
|
|
return -EPROBE_DEFER;
|
|
|
|
/* We may not have a GPIO based IRQ to scan, that is fine, we will
|
|
poll if so */
|
|
if (gpio_is_valid(eoc_gpio)) {
|
|
err = devm_gpio_request_one(&client->dev, eoc_gpio,
|
|
GPIOF_IN, "ak_8975");
|
|
if (err < 0) {
|
|
dev_err(&client->dev,
|
|
"failed to request GPIO %d, error %d\n",
|
|
eoc_gpio, err);
|
|
return err;
|
|
}
|
|
}
|
|
|
|
/* 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_gpio = eoc_gpio;
|
|
data->eoc_irq = 0;
|
|
|
|
/* id will be NULL when enumerated via ACPI */
|
|
if (id) {
|
|
chipset = (enum asahi_compass_chipset)(id->driver_data);
|
|
name = id->name;
|
|
} else if (ACPI_HANDLE(&client->dev))
|
|
name = ak8975_match_acpi_device(&client->dev, &chipset);
|
|
else
|
|
return -ENOSYS;
|
|
|
|
if (chipset >= AK_MAX_TYPE) {
|
|
dev_err(&client->dev, "AKM device type unsupported: %d\n",
|
|
chipset);
|
|
return -ENODEV;
|
|
}
|
|
|
|
data->def = &ak_def_array[chipset];
|
|
err = ak8975_who_i_am(client, data->def->type);
|
|
if (err < 0) {
|
|
dev_err(&client->dev, "Unexpected device\n");
|
|
return err;
|
|
}
|
|
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);
|
|
return err;
|
|
}
|
|
|
|
mutex_init(&data->lock);
|
|
indio_dev->dev.parent = &client->dev;
|
|
indio_dev->channels = ak8975_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
|
|
indio_dev->info = &ak8975_info;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->name = name;
|
|
return devm_iio_device_register(&client->dev, indio_dev);
|
|
}
|
|
|
|
static const struct i2c_device_id ak8975_id[] = {
|
|
{"ak8975", AK8975},
|
|
{"ak8963", AK8963},
|
|
{"AK8963", AK8963},
|
|
{"ak09911", AK09911},
|
|
{"ak09912", AK09912},
|
|
{}
|
|
};
|
|
|
|
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", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ak8975_of_match);
|
|
|
|
static struct i2c_driver ak8975_driver = {
|
|
.driver = {
|
|
.name = "ak8975",
|
|
.of_match_table = of_match_ptr(ak8975_of_match),
|
|
.acpi_match_table = ACPI_PTR(ak_acpi_match),
|
|
},
|
|
.probe = ak8975_probe,
|
|
.id_table = ak8975_id,
|
|
};
|
|
module_i2c_driver(ak8975_driver);
|
|
|
|
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
|
|
MODULE_DESCRIPTION("AK8975 magnetometer driver");
|
|
MODULE_LICENSE("GPL");
|