diff options
Diffstat (limited to 'drivers/iio/accel/sca3000.c')
-rw-r--r-- | drivers/iio/accel/sca3000.c | 1568 |
1 files changed, 1568 insertions, 0 deletions
diff --git a/drivers/iio/accel/sca3000.c b/drivers/iio/accel/sca3000.c new file mode 100644 index 000000000..194738660 --- /dev/null +++ b/drivers/iio/accel/sca3000.c @@ -0,0 +1,1568 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI + * + * Copyright (c) 2009 Jonathan Cameron <jic23@kernel.org> + * + * See industrialio/accels/sca3000.h for comments. + */ + +#include <linux/interrupt.h> +#include <linux/fs.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/sysfs.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/events.h> +#include <linux/iio/buffer.h> +#include <linux/iio/kfifo_buf.h> + +#define SCA3000_WRITE_REG(a) (((a) << 2) | 0x02) +#define SCA3000_READ_REG(a) ((a) << 2) + +#define SCA3000_REG_REVID_ADDR 0x00 +#define SCA3000_REG_REVID_MAJOR_MASK GENMASK(8, 4) +#define SCA3000_REG_REVID_MINOR_MASK GENMASK(3, 0) + +#define SCA3000_REG_STATUS_ADDR 0x02 +#define SCA3000_LOCKED BIT(5) +#define SCA3000_EEPROM_CS_ERROR BIT(1) +#define SCA3000_SPI_FRAME_ERROR BIT(0) + +/* All reads done using register decrement so no need to directly access LSBs */ +#define SCA3000_REG_X_MSB_ADDR 0x05 +#define SCA3000_REG_Y_MSB_ADDR 0x07 +#define SCA3000_REG_Z_MSB_ADDR 0x09 + +#define SCA3000_REG_RING_OUT_ADDR 0x0f + +/* Temp read untested - the e05 doesn't have the sensor */ +#define SCA3000_REG_TEMP_MSB_ADDR 0x13 + +#define SCA3000_REG_MODE_ADDR 0x14 +#define SCA3000_MODE_PROT_MASK 0x28 +#define SCA3000_REG_MODE_RING_BUF_ENABLE BIT(7) +#define SCA3000_REG_MODE_RING_BUF_8BIT BIT(6) + +/* + * Free fall detection triggers an interrupt if the acceleration + * is below a threshold for equivalent of 25cm drop + */ +#define SCA3000_REG_MODE_FREE_FALL_DETECT BIT(4) +#define SCA3000_REG_MODE_MEAS_MODE_NORMAL 0x00 +#define SCA3000_REG_MODE_MEAS_MODE_OP_1 0x01 +#define SCA3000_REG_MODE_MEAS_MODE_OP_2 0x02 + +/* + * In motion detection mode the accelerations are band pass filtered + * (approx 1 - 25Hz) and then a programmable threshold used to trigger + * and interrupt. + */ +#define SCA3000_REG_MODE_MEAS_MODE_MOT_DET 0x03 +#define SCA3000_REG_MODE_MODE_MASK 0x03 + +#define SCA3000_REG_BUF_COUNT_ADDR 0x15 + +#define SCA3000_REG_INT_STATUS_ADDR 0x16 +#define SCA3000_REG_INT_STATUS_THREE_QUARTERS BIT(7) +#define SCA3000_REG_INT_STATUS_HALF BIT(6) + +#define SCA3000_INT_STATUS_FREE_FALL BIT(3) +#define SCA3000_INT_STATUS_Y_TRIGGER BIT(2) +#define SCA3000_INT_STATUS_X_TRIGGER BIT(1) +#define SCA3000_INT_STATUS_Z_TRIGGER BIT(0) + +/* Used to allow access to multiplexed registers */ +#define SCA3000_REG_CTRL_SEL_ADDR 0x18 +/* Only available for SCA3000-D03 and SCA3000-D01 */ +#define SCA3000_REG_CTRL_SEL_I2C_DISABLE 0x01 +#define SCA3000_REG_CTRL_SEL_MD_CTRL 0x02 +#define SCA3000_REG_CTRL_SEL_MD_Y_TH 0x03 +#define SCA3000_REG_CTRL_SEL_MD_X_TH 0x04 +#define SCA3000_REG_CTRL_SEL_MD_Z_TH 0x05 +/* + * BE VERY CAREFUL WITH THIS, IF 3 BITS ARE NOT SET the device + * will not function + */ +#define SCA3000_REG_CTRL_SEL_OUT_CTRL 0x0B + +#define SCA3000_REG_OUT_CTRL_PROT_MASK 0xE0 +#define SCA3000_REG_OUT_CTRL_BUF_X_EN 0x10 +#define SCA3000_REG_OUT_CTRL_BUF_Y_EN 0x08 +#define SCA3000_REG_OUT_CTRL_BUF_Z_EN 0x04 +#define SCA3000_REG_OUT_CTRL_BUF_DIV_MASK 0x03 +#define SCA3000_REG_OUT_CTRL_BUF_DIV_4 0x02 +#define SCA3000_REG_OUT_CTRL_BUF_DIV_2 0x01 + + +/* + * Control which motion detector interrupts are on. + * For now only OR combinations are supported. + */ +#define SCA3000_MD_CTRL_PROT_MASK 0xC0 +#define SCA3000_MD_CTRL_OR_Y BIT(0) +#define SCA3000_MD_CTRL_OR_X BIT(1) +#define SCA3000_MD_CTRL_OR_Z BIT(2) +/* Currently unsupported */ +#define SCA3000_MD_CTRL_AND_Y BIT(3) +#define SCA3000_MD_CTRL_AND_X BIT(4) +#define SCA3000_MD_CTRL_AND_Z BIT(5) + +/* + * Some control registers of complex access methods requiring this register to + * be used to remove a lock. + */ +#define SCA3000_REG_UNLOCK_ADDR 0x1e + +#define SCA3000_REG_INT_MASK_ADDR 0x21 +#define SCA3000_REG_INT_MASK_PROT_MASK 0x1C + +#define SCA3000_REG_INT_MASK_RING_THREE_QUARTER BIT(7) +#define SCA3000_REG_INT_MASK_RING_HALF BIT(6) + +#define SCA3000_REG_INT_MASK_ALL_INTS 0x02 +#define SCA3000_REG_INT_MASK_ACTIVE_HIGH 0x01 +#define SCA3000_REG_INT_MASK_ACTIVE_LOW 0x00 +/* Values of multiplexed registers (write to ctrl_data after select) */ +#define SCA3000_REG_CTRL_DATA_ADDR 0x22 + +/* + * Measurement modes available on some sca3000 series chips. Code assumes others + * may become available in the future. + * + * Bypass - Bypass the low-pass filter in the signal channel so as to increase + * signal bandwidth. + * + * Narrow - Narrow low-pass filtering of the signal channel and half output + * data rate by decimation. + * + * Wide - Widen low-pass filtering of signal channel to increase bandwidth + */ +#define SCA3000_OP_MODE_BYPASS 0x01 +#define SCA3000_OP_MODE_NARROW 0x02 +#define SCA3000_OP_MODE_WIDE 0x04 +#define SCA3000_MAX_TX 6 +#define SCA3000_MAX_RX 2 + +/** + * struct sca3000_state - device instance state information + * @us: the associated spi device + * @info: chip variant information + * @last_timestamp: the timestamp of the last event + * @mo_det_use_count: reference counter for the motion detection unit + * @lock: lock used to protect elements of sca3000_state + * and the underlying device state. + * @tx: dma-able transmit buffer + * @rx: dma-able receive buffer + **/ +struct sca3000_state { + struct spi_device *us; + const struct sca3000_chip_info *info; + s64 last_timestamp; + int mo_det_use_count; + struct mutex lock; + /* Can these share a cacheline ? */ + u8 rx[384] ____cacheline_aligned; + u8 tx[6] ____cacheline_aligned; +}; + +/** + * struct sca3000_chip_info - model dependent parameters + * @scale: scale * 10^-6 + * @temp_output: some devices have temperature sensors. + * @measurement_mode_freq: normal mode sampling frequency + * @measurement_mode_3db_freq: 3db cutoff frequency of the low pass filter for + * the normal measurement mode. + * @option_mode_1: first optional mode. Not all models have one + * @option_mode_1_freq: option mode 1 sampling frequency + * @option_mode_1_3db_freq: 3db cutoff frequency of the low pass filter for + * the first option mode. + * @option_mode_2: second optional mode. Not all chips have one + * @option_mode_2_freq: option mode 2 sampling frequency + * @option_mode_2_3db_freq: 3db cutoff frequency of the low pass filter for + * the second option mode. + * @mot_det_mult_xz: Bit wise multipliers to calculate the threshold + * for motion detection in the x and z axis. + * @mot_det_mult_y: Bit wise multipliers to calculate the threshold + * for motion detection in the y axis. + * + * This structure is used to hold information about the functionality of a given + * sca3000 variant. + **/ +struct sca3000_chip_info { + unsigned int scale; + bool temp_output; + int measurement_mode_freq; + int measurement_mode_3db_freq; + int option_mode_1; + int option_mode_1_freq; + int option_mode_1_3db_freq; + int option_mode_2; + int option_mode_2_freq; + int option_mode_2_3db_freq; + int mot_det_mult_xz[6]; + int mot_det_mult_y[7]; +}; + +enum sca3000_variant { + d01, + e02, + e04, + e05, +}; + +/* + * Note where option modes are not defined, the chip simply does not + * support any. + * Other chips in the sca3000 series use i2c and are not included here. + * + * Some of these devices are only listed in the family data sheet and + * do not actually appear to be available. + */ +static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = { + [d01] = { + .scale = 7357, + .temp_output = true, + .measurement_mode_freq = 250, + .measurement_mode_3db_freq = 45, + .option_mode_1 = SCA3000_OP_MODE_BYPASS, + .option_mode_1_freq = 250, + .option_mode_1_3db_freq = 70, + .mot_det_mult_xz = {50, 100, 200, 350, 650, 1300}, + .mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750}, + }, + [e02] = { + .scale = 9810, + .measurement_mode_freq = 125, + .measurement_mode_3db_freq = 40, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 63, + .option_mode_1_3db_freq = 11, + .mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050}, + .mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700}, + }, + [e04] = { + .scale = 19620, + .measurement_mode_freq = 100, + .measurement_mode_3db_freq = 38, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 50, + .option_mode_1_3db_freq = 9, + .option_mode_2 = SCA3000_OP_MODE_WIDE, + .option_mode_2_freq = 400, + .option_mode_2_3db_freq = 70, + .mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100}, + .mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000}, + }, + [e05] = { + .scale = 61313, + .measurement_mode_freq = 200, + .measurement_mode_3db_freq = 60, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 50, + .option_mode_1_3db_freq = 9, + .option_mode_2 = SCA3000_OP_MODE_WIDE, + .option_mode_2_freq = 400, + .option_mode_2_3db_freq = 75, + .mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900}, + .mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600}, + }, +}; + +static int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val) +{ + st->tx[0] = SCA3000_WRITE_REG(address); + st->tx[1] = val; + return spi_write(st->us, st->tx, 2); +} + +static int sca3000_read_data_short(struct sca3000_state *st, + u8 reg_address_high, + int len) +{ + struct spi_transfer xfer[2] = { + { + .len = 1, + .tx_buf = st->tx, + }, { + .len = len, + .rx_buf = st->rx, + } + }; + st->tx[0] = SCA3000_READ_REG(reg_address_high); + + return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer)); +} + +/** + * sca3000_reg_lock_on() - test if the ctrl register lock is on + * @st: Driver specific device instance data. + * + * Lock must be held. + **/ +static int sca3000_reg_lock_on(struct sca3000_state *st) +{ + int ret; + + ret = sca3000_read_data_short(st, SCA3000_REG_STATUS_ADDR, 1); + if (ret < 0) + return ret; + + return !(st->rx[0] & SCA3000_LOCKED); +} + +/** + * __sca3000_unlock_reg_lock() - unlock the control registers + * @st: Driver specific device instance data. + * + * Note the device does not appear to support doing this in a single transfer. + * This should only ever be used as part of ctrl reg read. + * Lock must be held before calling this + */ +static int __sca3000_unlock_reg_lock(struct sca3000_state *st) +{ + struct spi_transfer xfer[3] = { + { + .len = 2, + .cs_change = 1, + .tx_buf = st->tx, + }, { + .len = 2, + .cs_change = 1, + .tx_buf = st->tx + 2, + }, { + .len = 2, + .tx_buf = st->tx + 4, + }, + }; + st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR); + st->tx[1] = 0x00; + st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR); + st->tx[3] = 0x50; + st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR); + st->tx[5] = 0xA0; + + return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer)); +} + +/** + * sca3000_write_ctrl_reg() write to a lock protect ctrl register + * @st: Driver specific device instance data. + * @sel: selects which registers we wish to write to + * @val: the value to be written + * + * Certain control registers are protected against overwriting by the lock + * register and use a shared write address. This function allows writing of + * these registers. + * Lock must be held. + */ +static int sca3000_write_ctrl_reg(struct sca3000_state *st, + u8 sel, + uint8_t val) +{ + int ret; + + ret = sca3000_reg_lock_on(st); + if (ret < 0) + goto error_ret; + if (ret) { + ret = __sca3000_unlock_reg_lock(st); + if (ret) + goto error_ret; + } + + /* Set the control select register */ + ret = sca3000_write_reg(st, SCA3000_REG_CTRL_SEL_ADDR, sel); + if (ret) + goto error_ret; + + /* Write the actual value into the register */ + ret = sca3000_write_reg(st, SCA3000_REG_CTRL_DATA_ADDR, val); + +error_ret: + return ret; +} + +/** + * sca3000_read_ctrl_reg() read from lock protected control register. + * @st: Driver specific device instance data. + * @ctrl_reg: Which ctrl register do we want to read. + * + * Lock must be held. + */ +static int sca3000_read_ctrl_reg(struct sca3000_state *st, + u8 ctrl_reg) +{ + int ret; + + ret = sca3000_reg_lock_on(st); + if (ret < 0) + goto error_ret; + if (ret) { + ret = __sca3000_unlock_reg_lock(st); + if (ret) + goto error_ret; + } + /* Set the control select register */ + ret = sca3000_write_reg(st, SCA3000_REG_CTRL_SEL_ADDR, ctrl_reg); + if (ret) + goto error_ret; + ret = sca3000_read_data_short(st, SCA3000_REG_CTRL_DATA_ADDR, 1); + if (ret) + goto error_ret; + return st->rx[0]; +error_ret: + return ret; +} + +/** + * sca3000_show_rev() - sysfs interface to read the chip revision number + * @indio_dev: Device instance specific generic IIO data. + * Driver specific device instance data can be obtained via + * via iio_priv(indio_dev) + */ +static int sca3000_print_rev(struct iio_dev *indio_dev) +{ + int ret; + struct sca3000_state *st = iio_priv(indio_dev); + + mutex_lock(&st->lock); + ret = sca3000_read_data_short(st, SCA3000_REG_REVID_ADDR, 1); + if (ret < 0) + goto error_ret; + dev_info(&indio_dev->dev, + "sca3000 revision major=%lu, minor=%lu\n", + st->rx[0] & SCA3000_REG_REVID_MAJOR_MASK, + st->rx[0] & SCA3000_REG_REVID_MINOR_MASK); +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + +static ssize_t +sca3000_show_available_3db_freqs(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct sca3000_state *st = iio_priv(indio_dev); + int len; + + len = sprintf(buf, "%d", st->info->measurement_mode_3db_freq); + if (st->info->option_mode_1) + len += sprintf(buf + len, " %d", + st->info->option_mode_1_3db_freq); + if (st->info->option_mode_2) + len += sprintf(buf + len, " %d", + st->info->option_mode_2_3db_freq); + len += sprintf(buf + len, "\n"); + + return len; +} + +static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available, + S_IRUGO, sca3000_show_available_3db_freqs, + NULL, 0); + +static const struct iio_event_spec sca3000_event = { + .type = IIO_EV_TYPE_MAG, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE), +}; + +/* + * Note the hack in the number of bits to pretend we have 2 more than + * we do in the fifo. + */ +#define SCA3000_CHAN(index, mod) \ + { \ + .type = IIO_ACCEL, \ + .modified = 1, \ + .channel2 = mod, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |\ + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),\ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\ + .address = index, \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 13, \ + .storagebits = 16, \ + .shift = 3, \ + .endianness = IIO_BE, \ + }, \ + .event_spec = &sca3000_event, \ + .num_event_specs = 1, \ + } + +static const struct iio_event_spec sca3000_freefall_event_spec = { + .type = IIO_EV_TYPE_MAG, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_PERIOD), +}; + +static const struct iio_chan_spec sca3000_channels[] = { + SCA3000_CHAN(0, IIO_MOD_X), + SCA3000_CHAN(1, IIO_MOD_Y), + SCA3000_CHAN(2, IIO_MOD_Z), + { + .type = IIO_ACCEL, + .modified = 1, + .channel2 = IIO_MOD_X_AND_Y_AND_Z, + .scan_index = -1, /* Fake channel */ + .event_spec = &sca3000_freefall_event_spec, + .num_event_specs = 1, + }, +}; + +static const struct iio_chan_spec sca3000_channels_with_temp[] = { + SCA3000_CHAN(0, IIO_MOD_X), + SCA3000_CHAN(1, IIO_MOD_Y), + SCA3000_CHAN(2, IIO_MOD_Z), + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + /* No buffer support */ + .scan_index = -1, + }, + { + .type = IIO_ACCEL, + .modified = 1, + .channel2 = IIO_MOD_X_AND_Y_AND_Z, + .scan_index = -1, /* Fake channel */ + .event_spec = &sca3000_freefall_event_spec, + .num_event_specs = 1, + }, +}; + +static u8 sca3000_addresses[3][3] = { + [0] = {SCA3000_REG_X_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_X_TH, + SCA3000_MD_CTRL_OR_X}, + [1] = {SCA3000_REG_Y_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_Y_TH, + SCA3000_MD_CTRL_OR_Y}, + [2] = {SCA3000_REG_Z_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_Z_TH, + SCA3000_MD_CTRL_OR_Z}, +}; + +/** + * __sca3000_get_base_freq() - obtain mode specific base frequency + * @st: Private driver specific device instance specific state. + * @info: chip type specific information. + * @base_freq: Base frequency for the current measurement mode. + * + * lock must be held + */ +static inline int __sca3000_get_base_freq(struct sca3000_state *st, + const struct sca3000_chip_info *info, + int *base_freq) +{ + int ret; + + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + goto error_ret; + switch (SCA3000_REG_MODE_MODE_MASK & st->rx[0]) { + case SCA3000_REG_MODE_MEAS_MODE_NORMAL: + *base_freq = info->measurement_mode_freq; + break; + case SCA3000_REG_MODE_MEAS_MODE_OP_1: + *base_freq = info->option_mode_1_freq; + break; + case SCA3000_REG_MODE_MEAS_MODE_OP_2: + *base_freq = info->option_mode_2_freq; + break; + default: + ret = -EINVAL; + } +error_ret: + return ret; +} + +/** + * sca3000_read_raw_samp_freq() - read_raw handler for IIO_CHAN_INFO_SAMP_FREQ + * @st: Private driver specific device instance specific state. + * @val: The frequency read back. + * + * lock must be held + **/ +static int sca3000_read_raw_samp_freq(struct sca3000_state *st, int *val) +{ + int ret; + + ret = __sca3000_get_base_freq(st, st->info, val); + if (ret) + return ret; + + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL); + if (ret < 0) + return ret; + + if (*val > 0) { + ret &= SCA3000_REG_OUT_CTRL_BUF_DIV_MASK; + switch (ret) { + case SCA3000_REG_OUT_CTRL_BUF_DIV_2: + *val /= 2; + break; + case SCA3000_REG_OUT_CTRL_BUF_DIV_4: + *val /= 4; + break; + } + } + + return 0; +} + +/** + * sca3000_write_raw_samp_freq() - write_raw handler for IIO_CHAN_INFO_SAMP_FREQ + * @st: Private driver specific device instance specific state. + * @val: The frequency desired. + * + * lock must be held + */ +static int sca3000_write_raw_samp_freq(struct sca3000_state *st, int val) +{ + int ret, base_freq, ctrlval; + + ret = __sca3000_get_base_freq(st, st->info, &base_freq); + if (ret) + return ret; + + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL); + if (ret < 0) + return ret; + + ctrlval = ret & ~SCA3000_REG_OUT_CTRL_BUF_DIV_MASK; + + if (val == base_freq / 2) + ctrlval |= SCA3000_REG_OUT_CTRL_BUF_DIV_2; + if (val == base_freq / 4) + ctrlval |= SCA3000_REG_OUT_CTRL_BUF_DIV_4; + else if (val != base_freq) + return -EINVAL; + + return sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, + ctrlval); +} + +static int sca3000_read_3db_freq(struct sca3000_state *st, int *val) +{ + int ret; + + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + return ret; + + /* mask bottom 2 bits - only ones that are relevant */ + st->rx[0] &= SCA3000_REG_MODE_MODE_MASK; + switch (st->rx[0]) { + case SCA3000_REG_MODE_MEAS_MODE_NORMAL: + *val = st->info->measurement_mode_3db_freq; + return IIO_VAL_INT; + case SCA3000_REG_MODE_MEAS_MODE_MOT_DET: + return -EBUSY; + case SCA3000_REG_MODE_MEAS_MODE_OP_1: + *val = st->info->option_mode_1_3db_freq; + return IIO_VAL_INT; + case SCA3000_REG_MODE_MEAS_MODE_OP_2: + *val = st->info->option_mode_2_3db_freq; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int sca3000_write_3db_freq(struct sca3000_state *st, int val) +{ + int ret; + int mode; + + if (val == st->info->measurement_mode_3db_freq) + mode = SCA3000_REG_MODE_MEAS_MODE_NORMAL; + else if (st->info->option_mode_1 && + (val == st->info->option_mode_1_3db_freq)) + mode = SCA3000_REG_MODE_MEAS_MODE_OP_1; + else if (st->info->option_mode_2 && + (val == st->info->option_mode_2_3db_freq)) + mode = SCA3000_REG_MODE_MEAS_MODE_OP_2; + else + return -EINVAL; + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + return ret; + + st->rx[0] &= ~SCA3000_REG_MODE_MODE_MASK; + st->rx[0] |= (mode & SCA3000_REG_MODE_MODE_MASK); + + return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, st->rx[0]); +} + +static int sca3000_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + u8 address; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + if (chan->type == IIO_ACCEL) { + if (st->mo_det_use_count) { + mutex_unlock(&st->lock); + return -EBUSY; + } + address = sca3000_addresses[chan->address][0]; + ret = sca3000_read_data_short(st, address, 2); + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + *val = (be16_to_cpup((__be16 *)st->rx) >> 3) & 0x1FFF; + *val = ((*val) << (sizeof(*val) * 8 - 13)) >> + (sizeof(*val) * 8 - 13); + } else { + /* get the temperature when available */ + ret = sca3000_read_data_short(st, + SCA3000_REG_TEMP_MSB_ADDR, + 2); + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + *val = ((st->rx[0] & 0x3F) << 3) | + ((st->rx[1] & 0xE0) >> 5); + } + mutex_unlock(&st->lock); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = 0; + if (chan->type == IIO_ACCEL) + *val2 = st->info->scale; + else /* temperature */ + *val2 = 555556; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_OFFSET: + *val = -214; + *val2 = 600000; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SAMP_FREQ: + mutex_lock(&st->lock); + ret = sca3000_read_raw_samp_freq(st, val); + mutex_unlock(&st->lock); + return ret ? ret : IIO_VAL_INT; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + mutex_lock(&st->lock); + ret = sca3000_read_3db_freq(st, val); + mutex_unlock(&st->lock); + return ret; + default: + return -EINVAL; + } +} + +static int sca3000_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + if (val2) + return -EINVAL; + mutex_lock(&st->lock); + ret = sca3000_write_raw_samp_freq(st, val); + mutex_unlock(&st->lock); + return ret; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + if (val2) + return -EINVAL; + mutex_lock(&st->lock); + ret = sca3000_write_3db_freq(st, val); + mutex_unlock(&st->lock); + return ret; + default: + return -EINVAL; + } + + return ret; +} + +/** + * sca3000_read_av_freq() - sysfs function to get available frequencies + * @dev: Device structure for this device. + * @attr: Description of the attribute. + * @buf: Incoming string + * + * The later modes are only relevant to the ring buffer - and depend on current + * mode. Note that data sheet gives rather wide tolerances for these so integer + * division will give good enough answer and not all chips have them specified + * at all. + **/ +static ssize_t sca3000_read_av_freq(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct sca3000_state *st = iio_priv(indio_dev); + int len = 0, ret, val; + + mutex_lock(&st->lock); + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + val = st->rx[0]; + mutex_unlock(&st->lock); + if (ret) + goto error_ret; + + switch (val & SCA3000_REG_MODE_MODE_MASK) { + case SCA3000_REG_MODE_MEAS_MODE_NORMAL: + len += sprintf(buf + len, "%d %d %d\n", + st->info->measurement_mode_freq, + st->info->measurement_mode_freq / 2, + st->info->measurement_mode_freq / 4); + break; + case SCA3000_REG_MODE_MEAS_MODE_OP_1: + len += sprintf(buf + len, "%d %d %d\n", + st->info->option_mode_1_freq, + st->info->option_mode_1_freq / 2, + st->info->option_mode_1_freq / 4); + break; + case SCA3000_REG_MODE_MEAS_MODE_OP_2: + len += sprintf(buf + len, "%d %d %d\n", + st->info->option_mode_2_freq, + st->info->option_mode_2_freq / 2, + st->info->option_mode_2_freq / 4); + break; + } + return len; +error_ret: + return ret; +} + +/* + * Should only really be registered if ring buffer support is compiled in. + * Does no harm however and doing it right would add a fair bit of complexity + */ +static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sca3000_read_av_freq); + +/* + * sca3000_read_event_value() - query of a threshold or period + */ +static int sca3000_read_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + enum iio_event_info info, + int *val, int *val2) +{ + struct sca3000_state *st = iio_priv(indio_dev); + long ret; + int i; + + switch (info) { + case IIO_EV_INFO_VALUE: + mutex_lock(&st->lock); + ret = sca3000_read_ctrl_reg(st, + sca3000_addresses[chan->address][1]); + mutex_unlock(&st->lock); + if (ret < 0) + return ret; + *val = 0; + if (chan->channel2 == IIO_MOD_Y) + for_each_set_bit(i, &ret, + ARRAY_SIZE(st->info->mot_det_mult_y)) + *val += st->info->mot_det_mult_y[i]; + else + for_each_set_bit(i, &ret, + ARRAY_SIZE(st->info->mot_det_mult_xz)) + *val += st->info->mot_det_mult_xz[i]; + + return IIO_VAL_INT; + case IIO_EV_INFO_PERIOD: + *val = 0; + *val2 = 226000; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +/** + * sca3000_write_value() - control of threshold and period + * @indio_dev: Device instance specific IIO information. + * @chan: Description of the channel for which the event is being + * configured. + * @type: The type of event being configured, here magnitude rising + * as everything else is read only. + * @dir: Direction of the event (here rising) + * @info: What information about the event are we configuring. + * Here the threshold only. + * @val: Integer part of the value being written.. + * @val2: Non integer part of the value being written. Here always 0. + */ +static int sca3000_write_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + enum iio_event_info info, + int val, int val2) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + int i; + u8 nonlinear = 0; + + if (chan->channel2 == IIO_MOD_Y) { + i = ARRAY_SIZE(st->info->mot_det_mult_y); + while (i > 0) + if (val >= st->info->mot_det_mult_y[--i]) { + nonlinear |= (1 << i); + val -= st->info->mot_det_mult_y[i]; + } + } else { + i = ARRAY_SIZE(st->info->mot_det_mult_xz); + while (i > 0) + if (val >= st->info->mot_det_mult_xz[--i]) { + nonlinear |= (1 << i); + val -= st->info->mot_det_mult_xz[i]; + } + } + + mutex_lock(&st->lock); + ret = sca3000_write_ctrl_reg(st, + sca3000_addresses[chan->address][1], + nonlinear); + mutex_unlock(&st->lock); + + return ret; +} + +static struct attribute *sca3000_attributes[] = { + &iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr, + &iio_dev_attr_sampling_frequency_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group sca3000_attribute_group = { + .attrs = sca3000_attributes, +}; + +static int sca3000_read_data(struct sca3000_state *st, + u8 reg_address_high, + u8 *rx, + int len) +{ + int ret; + struct spi_transfer xfer[2] = { + { + .len = 1, + .tx_buf = st->tx, + }, { + .len = len, + .rx_buf = rx, + } + }; + + st->tx[0] = SCA3000_READ_REG(reg_address_high); + ret = spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer)); + if (ret) { + dev_err(&st->us->dev, "problem reading register\n"); + return ret; + } + + return 0; +} + +/** + * sca3000_ring_int_process() - ring specific interrupt handling. + * @val: Value of the interrupt status register. + * @indio_dev: Device instance specific IIO device structure. + */ +static void sca3000_ring_int_process(u8 val, struct iio_dev *indio_dev) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret, i, num_available; + + mutex_lock(&st->lock); + + if (val & SCA3000_REG_INT_STATUS_HALF) { + ret = sca3000_read_data_short(st, SCA3000_REG_BUF_COUNT_ADDR, + 1); + if (ret) + goto error_ret; + num_available = st->rx[0]; + /* + * num_available is the total number of samples available + * i.e. number of time points * number of channels. + */ + ret = sca3000_read_data(st, SCA3000_REG_RING_OUT_ADDR, st->rx, + num_available * 2); + if (ret) + goto error_ret; + for (i = 0; i < num_available / 3; i++) { + /* + * Dirty hack to cover for 11 bit in fifo, 13 bit + * direct reading. + * + * In theory the bottom two bits are undefined. + * In reality they appear to always be 0. + */ + iio_push_to_buffers(indio_dev, st->rx + i * 3 * 2); + } + } +error_ret: + mutex_unlock(&st->lock); +} + +/** + * sca3000_event_handler() - handling ring and non ring events + * @irq: The irq being handled. + * @private: struct iio_device pointer for the device. + * + * Ring related interrupt handler. Depending on event, push to + * the ring buffer event chrdev or the event one. + * + * This function is complicated by the fact that the devices can signify ring + * and non ring events via the same interrupt line and they can only + * be distinguished via a read of the relevant status register. + */ +static irqreturn_t sca3000_event_handler(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct sca3000_state *st = iio_priv(indio_dev); + int ret, val; + s64 last_timestamp = iio_get_time_ns(indio_dev); + + /* + * Could lead if badly timed to an extra read of status reg, + * but ensures no interrupt is missed. + */ + mutex_lock(&st->lock); + ret = sca3000_read_data_short(st, SCA3000_REG_INT_STATUS_ADDR, 1); + val = st->rx[0]; + mutex_unlock(&st->lock); + if (ret) + goto done; + + sca3000_ring_int_process(val, indio_dev); + + if (val & SCA3000_INT_STATUS_FREE_FALL) + iio_push_event(indio_dev, + IIO_MOD_EVENT_CODE(IIO_ACCEL, + 0, + IIO_MOD_X_AND_Y_AND_Z, + IIO_EV_TYPE_MAG, + IIO_EV_DIR_FALLING), + last_timestamp); + + if (val & SCA3000_INT_STATUS_Y_TRIGGER) + iio_push_event(indio_dev, + IIO_MOD_EVENT_CODE(IIO_ACCEL, + 0, + IIO_MOD_Y, + IIO_EV_TYPE_MAG, + IIO_EV_DIR_RISING), + last_timestamp); + + if (val & SCA3000_INT_STATUS_X_TRIGGER) + iio_push_event(indio_dev, + IIO_MOD_EVENT_CODE(IIO_ACCEL, + 0, + IIO_MOD_X, + IIO_EV_TYPE_MAG, + IIO_EV_DIR_RISING), + last_timestamp); + + if (val & SCA3000_INT_STATUS_Z_TRIGGER) + iio_push_event(indio_dev, + IIO_MOD_EVENT_CODE(IIO_ACCEL, + 0, + IIO_MOD_Z, + IIO_EV_TYPE_MAG, + IIO_EV_DIR_RISING), + last_timestamp); + +done: + return IRQ_HANDLED; +} + +/* + * sca3000_read_event_config() what events are enabled + */ +static int sca3000_read_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + /* read current value of mode register */ + mutex_lock(&st->lock); + + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + goto error_ret; + + switch (chan->channel2) { + case IIO_MOD_X_AND_Y_AND_Z: + ret = !!(st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT); + break; + case IIO_MOD_X: + case IIO_MOD_Y: + case IIO_MOD_Z: + /* + * Motion detection mode cannot run at the same time as + * acceleration data being read. + */ + if ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK) + != SCA3000_REG_MODE_MEAS_MODE_MOT_DET) { + ret = 0; + } else { + ret = sca3000_read_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL); + if (ret < 0) + goto error_ret; + /* only supporting logical or's for now */ + ret = !!(ret & sca3000_addresses[chan->address][2]); + } + break; + default: + ret = -EINVAL; + } + +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + +static int sca3000_freefall_set_state(struct iio_dev *indio_dev, int state) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + + /* read current value of mode register */ + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + return ret; + + /* if off and should be on */ + if (state && !(st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT)) + return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, + st->rx[0] | SCA3000_REG_MODE_FREE_FALL_DETECT); + /* if on and should be off */ + else if (!state && (st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT)) + return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, + st->rx[0] & ~SCA3000_REG_MODE_FREE_FALL_DETECT); + else + return 0; +} + +static int sca3000_motion_detect_set_state(struct iio_dev *indio_dev, int axis, + int state) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret, ctrlval; + + /* + * First read the motion detector config to find out if + * this axis is on + */ + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL); + if (ret < 0) + return ret; + ctrlval = ret; + /* if off and should be on */ + if (state && !(ctrlval & sca3000_addresses[axis][2])) { + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + ctrlval | + sca3000_addresses[axis][2]); + if (ret) + return ret; + st->mo_det_use_count++; + } else if (!state && (ctrlval & sca3000_addresses[axis][2])) { + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + ctrlval & + ~(sca3000_addresses[axis][2])); + if (ret) + return ret; + st->mo_det_use_count--; + } + + /* read current value of mode register */ + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + return ret; + /* if off and should be on */ + if ((st->mo_det_use_count) && + ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK) + != SCA3000_REG_MODE_MEAS_MODE_MOT_DET)) + return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, + (st->rx[0] & ~SCA3000_REG_MODE_MODE_MASK) + | SCA3000_REG_MODE_MEAS_MODE_MOT_DET); + /* if on and should be off */ + else if (!(st->mo_det_use_count) && + ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK) + == SCA3000_REG_MODE_MEAS_MODE_MOT_DET)) + return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, + st->rx[0] & SCA3000_REG_MODE_MODE_MASK); + else + return 0; +} + +/** + * sca3000_write_event_config() - simple on off control for motion detector + * @indio_dev: IIO device instance specific structure. Data specific to this + * particular driver may be accessed via iio_priv(indio_dev). + * @chan: Description of the channel whose event we are configuring. + * @type: The type of event. + * @dir: The direction of the event. + * @state: Desired state of event being configured. + * + * This is a per axis control, but enabling any will result in the + * motion detector unit being enabled. + * N.B. enabling motion detector stops normal data acquisition. + * There is a complexity in knowing which mode to return to when + * this mode is disabled. Currently normal mode is assumed. + **/ +static int sca3000_write_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + int state) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + switch (chan->channel2) { + case IIO_MOD_X_AND_Y_AND_Z: + ret = sca3000_freefall_set_state(indio_dev, state); + break; + + case IIO_MOD_X: + case IIO_MOD_Y: + case IIO_MOD_Z: + ret = sca3000_motion_detect_set_state(indio_dev, + chan->address, + state); + break; + default: + ret = -EINVAL; + break; + } + mutex_unlock(&st->lock); + + return ret; +} + +static int sca3000_configure_ring(struct iio_dev *indio_dev) +{ + struct iio_buffer *buffer; + + buffer = devm_iio_kfifo_allocate(&indio_dev->dev); + if (!buffer) + return -ENOMEM; + + iio_device_attach_buffer(indio_dev, buffer); + indio_dev->modes |= INDIO_BUFFER_SOFTWARE; + + return 0; +} + +static inline +int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state) +{ + struct sca3000_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + goto error_ret; + if (state) { + dev_info(&indio_dev->dev, "supposedly enabling ring buffer\n"); + ret = sca3000_write_reg(st, + SCA3000_REG_MODE_ADDR, + (st->rx[0] | SCA3000_REG_MODE_RING_BUF_ENABLE)); + } else + ret = sca3000_write_reg(st, + SCA3000_REG_MODE_ADDR, + (st->rx[0] & ~SCA3000_REG_MODE_RING_BUF_ENABLE)); +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + +/** + * sca3000_hw_ring_preenable() - hw ring buffer preenable function + * @indio_dev: structure representing the IIO device. Device instance + * specific state can be accessed via iio_priv(indio_dev). + * + * Very simple enable function as the chip will allows normal reads + * during ring buffer operation so as long as it is indeed running + * before we notify the core, the precise ordering does not matter. + */ +static int sca3000_hw_ring_preenable(struct iio_dev *indio_dev) +{ + int ret; + struct sca3000_state *st = iio_priv(indio_dev); + + mutex_lock(&st->lock); + + /* Enable the 50% full interrupt */ + ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1); + if (ret) + goto error_unlock; + ret = sca3000_write_reg(st, + SCA3000_REG_INT_MASK_ADDR, + st->rx[0] | SCA3000_REG_INT_MASK_RING_HALF); + if (ret) + goto error_unlock; + + mutex_unlock(&st->lock); + + return __sca3000_hw_ring_state_set(indio_dev, 1); + +error_unlock: + mutex_unlock(&st->lock); + + return ret; +} + +static int sca3000_hw_ring_postdisable(struct iio_dev *indio_dev) +{ + int ret; + struct sca3000_state *st = iio_priv(indio_dev); + + ret = __sca3000_hw_ring_state_set(indio_dev, 0); + if (ret) + return ret; + + /* Disable the 50% full interrupt */ + mutex_lock(&st->lock); + + ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1); + if (ret) + goto unlock; + ret = sca3000_write_reg(st, + SCA3000_REG_INT_MASK_ADDR, + st->rx[0] & ~SCA3000_REG_INT_MASK_RING_HALF); +unlock: + mutex_unlock(&st->lock); + return ret; +} + +static const struct iio_buffer_setup_ops sca3000_ring_setup_ops = { + .preenable = &sca3000_hw_ring_preenable, + .postdisable = &sca3000_hw_ring_postdisable, +}; + +/** + * sca3000_clean_setup() - get the device into a predictable state + * @st: Device instance specific private data structure + * + * Devices use flash memory to store many of the register values + * and hence can come up in somewhat unpredictable states. + * Hence reset everything on driver load. + */ +static int sca3000_clean_setup(struct sca3000_state *st) +{ + int ret; + + mutex_lock(&st->lock); + /* Ensure all interrupts have been acknowledged */ + ret = sca3000_read_data_short(st, SCA3000_REG_INT_STATUS_ADDR, 1); + if (ret) + goto error_ret; + + /* Turn off all motion detection channels */ + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL); + if (ret < 0) + goto error_ret; + ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL, + ret & SCA3000_MD_CTRL_PROT_MASK); + if (ret) + goto error_ret; + + /* Disable ring buffer */ + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL); + if (ret < 0) + goto error_ret; + ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, + (ret & SCA3000_REG_OUT_CTRL_PROT_MASK) + | SCA3000_REG_OUT_CTRL_BUF_X_EN + | SCA3000_REG_OUT_CTRL_BUF_Y_EN + | SCA3000_REG_OUT_CTRL_BUF_Z_EN + | SCA3000_REG_OUT_CTRL_BUF_DIV_4); + if (ret) + goto error_ret; + /* Enable interrupts, relevant to mode and set up as active low */ + ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, + SCA3000_REG_INT_MASK_ADDR, + (ret & SCA3000_REG_INT_MASK_PROT_MASK) + | SCA3000_REG_INT_MASK_ACTIVE_LOW); + if (ret) + goto error_ret; + /* + * Select normal measurement mode, free fall off, ring off + * Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5 + * as that occurs in one of the example on the datasheet + */ + ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, + (st->rx[0] & SCA3000_MODE_PROT_MASK)); + +error_ret: + mutex_unlock(&st->lock); + return ret; +} + +static const struct iio_info sca3000_info = { + .attrs = &sca3000_attribute_group, + .read_raw = &sca3000_read_raw, + .write_raw = &sca3000_write_raw, + .read_event_value = &sca3000_read_event_value, + .write_event_value = &sca3000_write_event_value, + .read_event_config = &sca3000_read_event_config, + .write_event_config = &sca3000_write_event_config, +}; + +static int sca3000_probe(struct spi_device *spi) +{ + int ret; + struct sca3000_state *st; + struct iio_dev *indio_dev; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + st->us = spi; + mutex_init(&st->lock); + st->info = &sca3000_spi_chip_info_tbl[spi_get_device_id(spi) + ->driver_data]; + + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->info = &sca3000_info; + if (st->info->temp_output) { + indio_dev->channels = sca3000_channels_with_temp; + indio_dev->num_channels = + ARRAY_SIZE(sca3000_channels_with_temp); + } else { + indio_dev->channels = sca3000_channels; + indio_dev->num_channels = ARRAY_SIZE(sca3000_channels); + } + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = sca3000_configure_ring(indio_dev); + if (ret) + return ret; + + if (spi->irq) { + ret = request_threaded_irq(spi->irq, + NULL, + &sca3000_event_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + "sca3000", + indio_dev); + if (ret) + return ret; + } + indio_dev->setup_ops = &sca3000_ring_setup_ops; + ret = sca3000_clean_setup(st); + if (ret) + goto error_free_irq; + + ret = sca3000_print_rev(indio_dev); + if (ret) + goto error_free_irq; + + return iio_device_register(indio_dev); + +error_free_irq: + if (spi->irq) + free_irq(spi->irq, indio_dev); + + return ret; +} + +static int sca3000_stop_all_interrupts(struct sca3000_state *st) +{ + int ret; + + mutex_lock(&st->lock); + ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, SCA3000_REG_INT_MASK_ADDR, + (st->rx[0] & + ~(SCA3000_REG_INT_MASK_RING_THREE_QUARTER | + SCA3000_REG_INT_MASK_RING_HALF | + SCA3000_REG_INT_MASK_ALL_INTS))); +error_ret: + mutex_unlock(&st->lock); + return ret; +} + +static int sca3000_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct sca3000_state *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + /* Must ensure no interrupts can be generated after this! */ + sca3000_stop_all_interrupts(st); + if (spi->irq) + free_irq(spi->irq, indio_dev); + + return 0; +} + +static const struct spi_device_id sca3000_id[] = { + {"sca3000_d01", d01}, + {"sca3000_e02", e02}, + {"sca3000_e04", e04}, + {"sca3000_e05", e05}, + {} +}; +MODULE_DEVICE_TABLE(spi, sca3000_id); + +static struct spi_driver sca3000_driver = { + .driver = { + .name = "sca3000", + }, + .probe = sca3000_probe, + .remove = sca3000_remove, + .id_table = sca3000_id, +}; +module_spi_driver(sca3000_driver); + +MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); +MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver"); +MODULE_LICENSE("GPL v2"); |