diff options
Diffstat (limited to 'drivers/staging/iio/accel/sca3000_core.c')
| -rw-r--r-- | drivers/staging/iio/accel/sca3000_core.c | 1509 |
1 files changed, 1509 insertions, 0 deletions
diff --git a/drivers/staging/iio/accel/sca3000_core.c b/drivers/staging/iio/accel/sca3000_core.c new file mode 100644 index 000000000000..e27e3b7d1003 --- /dev/null +++ b/drivers/staging/iio/accel/sca3000_core.c @@ -0,0 +1,1509 @@ +/* + * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk> + * + * See industrialio/accels/sca3000.h for comments. + */ + +#include <linux/interrupt.h> +#include <linux/gpio.h> +#include <linux/fs.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/sysfs.h> +#include "../iio.h" +#include "../sysfs.h" +#include "../ring_generic.h" + +#include "accel.h" +#include "sca3000.h" + +enum sca3000_variant { + d01, + d03, + e02, + e04, + e05, + l01, +}; + +/* 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[] = { + { + .name = "sca3000-d01", + .temp_output = true, + .measurement_mode_freq = 250, + .option_mode_1 = SCA3000_OP_MODE_BYPASS, + .option_mode_1_freq = 250, + }, { + /* No data sheet available - may be the same as the 3100-d03?*/ + .name = "sca3000-d03", + .temp_output = true, + }, { + .name = "sca3000-e02", + .measurement_mode_freq = 125, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 63, + }, { + .name = "sca3000-e04", + .measurement_mode_freq = 100, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 50, + .option_mode_2 = SCA3000_OP_MODE_WIDE, + .option_mode_2_freq = 400, + }, { + .name = "sca3000-e05", + .measurement_mode_freq = 200, + .option_mode_1 = SCA3000_OP_MODE_NARROW, + .option_mode_1_freq = 50, + .option_mode_2 = SCA3000_OP_MODE_WIDE, + .option_mode_2_freq = 400, + }, { + /* No data sheet available. + * Frequencies are unknown. + */ + .name = "sca3000-l01", + .temp_output = true, + .option_mode_1 = SCA3000_OP_MODE_BYPASS, + }, +}; + + +int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val) +{ + struct spi_transfer xfer = { + .bits_per_word = 8, + .len = 2, + .cs_change = 1, + .tx_buf = st->tx, + }; + struct spi_message msg; + + st->tx[0] = SCA3000_WRITE_REG(address); + st->tx[1] = val; + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + + return spi_sync(st->us, &msg); +} + +int sca3000_read_data(struct sca3000_state *st, + uint8_t reg_address_high, + u8 **rx_p, + int len) +{ + int ret; + struct spi_message msg; + struct spi_transfer xfer = { + .bits_per_word = 8, + .len = len + 1, + .cs_change = 1, + .tx_buf = st->tx, + }; + + *rx_p = kmalloc(len + 1, GFP_KERNEL); + if (*rx_p == NULL) { + ret = -ENOMEM; + goto error_ret; + } + xfer.rx_buf = *rx_p; + st->tx[0] = SCA3000_READ_REG(reg_address_high); + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + + ret = spi_sync(st->us, &msg); + + if (ret) { + dev_err(get_device(&st->us->dev), "problem reading register"); + goto error_free_rx; + } + + return 0; +error_free_rx: + kfree(*rx_p); +error_ret: + return ret; + +} +/** + * sca3000_reg_lock_on() test if the ctrl register lock is on + * + * Lock must be held. + **/ +static int sca3000_reg_lock_on(struct sca3000_state *st) +{ + u8 *rx; + int ret; + + ret = sca3000_read_data(st, SCA3000_REG_ADDR_STATUS, &rx, 1); + + if (ret < 0) + return ret; + ret = !(rx[1] & SCA3000_LOCKED); + kfree(rx); + + return ret; +} + +/** + * __sca3000_unlock_reg_lock() unlock the control registers + * + * 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_message msg; + struct spi_transfer xfer[3] = { + { + .bits_per_word = 8, + .len = 2, + .cs_change = 1, + .tx_buf = st->tx, + }, { + .bits_per_word = 8, + .len = 2, + .cs_change = 1, + .tx_buf = st->tx + 2, + }, { + .bits_per_word = 8, + .len = 2, + .cs_change = 1, + .tx_buf = st->tx + 4, + }, + }; + st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK); + st->tx[1] = 0x00; + st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK); + st->tx[3] = 0x50; + st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK); + st->tx[5] = 0xA0; + spi_message_init(&msg); + spi_message_add_tail(&xfer[0], &msg); + spi_message_add_tail(&xfer[1], &msg); + spi_message_add_tail(&xfer[2], &msg); + + return spi_sync(st->us, &msg); +} + +/** + * sca3000_write_ctrl_reg() write to a lock protect ctrl register + * @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, + uint8_t 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_ADDR_CTRL_SEL, sel); + if (ret) + goto error_ret; + + /* Write the actual value into the register */ + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_DATA, val); + +error_ret: + return ret; +} + +/* Crucial that lock is called before calling this */ +/** + * sca3000_read_ctrl_reg() read from lock protected control register. + * + * Lock must be held. + **/ +static int sca3000_read_ctrl_reg(struct sca3000_state *st, + u8 ctrl_reg, + u8 **rx_p) +{ + 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_ADDR_CTRL_SEL, ctrl_reg); + if (ret) + goto error_ret; + ret = sca3000_read_data(st, SCA3000_REG_ADDR_CTRL_DATA, rx_p, 1); + +error_ret: + return ret; +} + +#ifdef SCA3000_DEBUG +/** + * sca3000_check_status() check the status register + * + * Only used for debugging purposes + **/ +static int sca3000_check_status(struct device *dev) +{ + u8 *rx; + int ret; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_STATUS, &rx, 1); + if (ret < 0) + goto error_ret; + if (rx[1] & SCA3000_EEPROM_CS_ERROR) + dev_err(dev, "eeprom error \n"); + if (rx[1] & SCA3000_SPI_FRAME_ERROR) + dev_err(dev, "Previous SPI Frame was corrupt\n"); + kfree(rx); + +error_ret: + mutex_unlock(&st->lock); + return ret; +} +#endif /* SCA3000_DEBUG */ + +/** + * sca3000_read_13bit_signed() sysfs interface to read 13 bit signed registers + * + * These are described as signed 12 bit on the data sheet, which appears + * to be a conventional 2's complement 13 bit. + **/ +static ssize_t sca3000_read_13bit_signed(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + int len = 0, ret; + int val; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + u8 *rx; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, this_attr->address, &rx, 2); + if (ret < 0) + goto error_ret; + val = sca3000_13bit_convert(rx[1], rx[2]); + len += sprintf(buf + len, "%d\n", val); + kfree(rx); +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + + +static ssize_t sca3000_show_name(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct sca3000_state *st = dev_info->dev_data; + return sprintf(buf, "%s\n", st->info->name); +} +/** + * sca3000_show_reg() - sysfs interface to read the chip revision number + **/ +static ssize_t sca3000_show_rev(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + int len = 0, ret; + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct sca3000_state *st = dev_info->dev_data; + + u8 *rx; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_REVID, &rx, 1); + if (ret < 0) + goto error_ret; + len += sprintf(buf + len, + "major=%d, minor=%d\n", + rx[1] & SCA3000_REVID_MAJOR_MASK, + rx[1] & SCA3000_REVID_MINOR_MASK); + kfree(rx); + +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/** + * sca3000_show_available_measurement_modes() display available modes + * + * This is all read from chip specific data in the driver. Not all + * of the sca3000 series support modes other than normal. + **/ +static ssize_t +sca3000_show_available_measurement_modes(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct sca3000_state *st = dev_info->dev_data; + int len = 0; + + len += sprintf(buf + len, "0 - normal mode"); + switch (st->info->option_mode_1) { + case SCA3000_OP_MODE_NARROW: + len += sprintf(buf + len, ", 1 - narrow mode"); + break; + case SCA3000_OP_MODE_BYPASS: + len += sprintf(buf + len, ", 1 - bypass mode"); + break; + }; + switch (st->info->option_mode_2) { + case SCA3000_OP_MODE_WIDE: + len += sprintf(buf + len, ", 2 - wide mode"); + break; + } + /* always supported */ + len += sprintf(buf + len, " 3 - motion detection \n"); + + return len; +} + +/** + * sca3000_show_measurmenet_mode() sysfs read of current mode + **/ +static ssize_t +sca3000_show_measurement_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct sca3000_state *st = dev_info->dev_data; + int len = 0, ret; + u8 *rx; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto error_ret; + /* mask bottom 2 bits - only ones that are relevant */ + rx[1] &= 0x03; + switch (rx[1]) { + case SCA3000_MEAS_MODE_NORMAL: + len += sprintf(buf + len, "0 - normal mode\n"); + break; + case SCA3000_MEAS_MODE_MOT_DET: + len += sprintf(buf + len, "3 - motion detection\n"); + break; + case SCA3000_MEAS_MODE_OP_1: + switch (st->info->option_mode_1) { + case SCA3000_OP_MODE_NARROW: + len += sprintf(buf + len, "1 - narrow mode\n"); + break; + case SCA3000_OP_MODE_BYPASS: + len += sprintf(buf + len, "1 - bypass mode\n"); + break; + }; + break; + case SCA3000_MEAS_MODE_OP_2: + switch (st->info->option_mode_2) { + case SCA3000_OP_MODE_WIDE: + len += sprintf(buf + len, "2 - wide mode\n"); + break; + } + break; + }; + +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/** + * sca3000_store_measurement_mode() set the current mode + **/ +static ssize_t +sca3000_store_measurement_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct sca3000_state *st = dev_info->dev_data; + int ret; + u8 *rx; + int mask = 0x03; + long val; + + mutex_lock(&st->lock); + ret = strict_strtol(buf, 10, &val); + if (ret) + goto error_ret; + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto error_ret; + rx[1] &= ~mask; + rx[1] |= (val & mask); + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, rx[1]); + if (ret) + goto error_free_rx; + mutex_unlock(&st->lock); + + return len; + +error_free_rx: + kfree(rx); +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + + +/* Not even vaguely standard attributes so defined here rather than + * in the relevant IIO core headers + */ +static IIO_DEVICE_ATTR(available_measurement_modes, S_IRUGO, + sca3000_show_available_measurement_modes, + NULL, 0); + +static IIO_DEVICE_ATTR(measurement_mode, S_IRUGO | S_IWUSR, + sca3000_show_measurement_mode, + sca3000_store_measurement_mode, + 0); + +/* More standard attributes */ + +static IIO_DEV_ATTR_NAME(sca3000_show_name); +static IIO_DEV_ATTR_REV(sca3000_show_rev); + +static IIO_DEV_ATTR_ACCEL_X(sca3000_read_13bit_signed, + SCA3000_REG_ADDR_X_MSB); +static IIO_DEV_ATTR_ACCEL_Y(sca3000_read_13bit_signed, + SCA3000_REG_ADDR_Y_MSB); +static IIO_DEV_ATTR_ACCEL_Z(sca3000_read_13bit_signed, + SCA3000_REG_ADDR_Z_MSB); + + +/** + * sca3000_read_av_freq() sysfs function to get available frequencies + * + * 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_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + int len = 0, ret; + u8 *rx; + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + mutex_unlock(&st->lock); + if (ret) + goto error_ret; + rx[1] &= 0x03; + switch (rx[1]) { + case SCA3000_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_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_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; + }; + kfree(rx); + return len; +error_ret: + return ret; +} +/** + * __sca3000_get_base_frequency() obtain mode specific base frequency + * + * 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; + u8 *rx; + + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto error_ret; + switch (0x03 & rx[1]) { + case SCA3000_MEAS_MODE_NORMAL: + *base_freq = info->measurement_mode_freq; + break; + case SCA3000_MEAS_MODE_OP_1: + *base_freq = info->option_mode_1_freq; + break; + case SCA3000_MEAS_MODE_OP_2: + *base_freq = info->option_mode_2_freq; + break; + }; + kfree(rx); +error_ret: + return ret; +} + +/** + * sca3000_read_frequency() sysfs interface to get the current frequency + **/ +static ssize_t sca3000_read_frequency(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + int ret, len = 0, base_freq = 0; + u8 *rx; + mutex_lock(&st->lock); + ret = __sca3000_get_base_freq(st, st->info, &base_freq); + if (ret) + goto error_ret_mut; + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, &rx); + mutex_unlock(&st->lock); + if (ret) + goto error_ret; + if (base_freq > 0) + switch (rx[1]&0x03) { + case 0x00: + case 0x03: + len = sprintf(buf, "%d\n", base_freq); + break; + case 0x01: + len = sprintf(buf, "%d\n", base_freq/2); + break; + case 0x02: + len = sprintf(buf, "%d\n", base_freq/4); + break; + }; + kfree(rx); + return len; +error_ret_mut: + mutex_unlock(&st->lock); +error_ret: + return ret; +} + +/** + * sca3000_set_frequency() sysfs interface to set the current frequency + **/ +static ssize_t sca3000_set_frequency(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + int ret, base_freq = 0; + u8 *rx; + long val; + + ret = strict_strtol(buf, 10, &val); + if (ret) + return ret; + + mutex_lock(&st->lock); + /* What mode are we in? */ + ret = __sca3000_get_base_freq(st, st->info, &base_freq); + if (ret) + goto error_free_lock; + + ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, &rx); + if (ret) + goto error_free_lock; + /* clear the bits */ + rx[1] &= ~0x03; + + if (val == base_freq/2) { + rx[1] |= SCA3000_OUT_CTRL_BUF_DIV_2; + } else if (val == base_freq/4) { + rx[1] |= SCA3000_OUT_CTRL_BUF_DIV_4; + } else if (val != base_freq) { + ret = -EINVAL; + goto error_free_lock; + } + ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, rx[1]); +error_free_lock: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/* 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_AVAIL_SAMP_FREQ(sca3000_read_av_freq); + +static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO, + sca3000_read_frequency, + sca3000_set_frequency); + + +/** + * sca3000_read_temp() sysfs interface to get the temperature when available + * +* The alignment of data in here is downright odd. See data sheet. +* Converting this into a meaningful value is left to inline functions in +* userspace part of header. +**/ +static ssize_t sca3000_read_temp(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + int len = 0, ret; + int val; + u8 *rx; + ret = sca3000_read_data(st, SCA3000_REG_ADDR_TEMP_MSB, &rx, 2); + if (ret < 0) + goto error_ret; + val = ((rx[1]&0x3F) << 3) | ((rx[2] & 0xE0) >> 5); + len += sprintf(buf + len, "%d\n", val); + kfree(rx); + + return len; + +error_ret: + return ret; +} +static IIO_DEV_ATTR_TEMP(sca3000_read_temp); + +/** + * sca3000_show_thresh() sysfs query of a theshold + **/ +static ssize_t sca3000_show_thresh(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int len = 0, ret; + u8 *rx; + + mutex_lock(&st->lock); + ret = sca3000_read_ctrl_reg(st, + this_attr->address, + &rx); + mutex_unlock(&st->lock); + if (ret) + return ret; + len += sprintf(buf + len, "%d\n", rx[1]); + kfree(rx); + + return len; +} + +/** + * sca3000_write_thresh() sysfs control of threshold + **/ +static ssize_t sca3000_write_thresh(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int ret; + long val; + + ret = strict_strtol(buf, 10, &val); + if (ret) + return ret; + mutex_lock(&st->lock); + ret = sca3000_write_ctrl_reg(st, this_attr->address, val); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static IIO_DEV_ATTR_ACCEL_THRESH_X(S_IRUGO | S_IWUSR, + sca3000_show_thresh, + sca3000_write_thresh, + SCA3000_REG_CTRL_SEL_MD_X_TH); +static IIO_DEV_ATTR_ACCEL_THRESH_Y(S_IRUGO | S_IWUSR, + sca3000_show_thresh, + sca3000_write_thresh, + SCA3000_REG_CTRL_SEL_MD_Y_TH); +static IIO_DEV_ATTR_ACCEL_THRESH_Z(S_IRUGO | S_IWUSR, + sca3000_show_thresh, + sca3000_write_thresh, + SCA3000_REG_CTRL_SEL_MD_Z_TH); + +static struct attribute *sca3000_attributes[] = { + &iio_dev_attr_name.dev_attr.attr, + &iio_dev_attr_revision.dev_attr.attr, + &iio_dev_attr_accel_x.dev_attr.attr, + &iio_dev_attr_accel_y.dev_attr.attr, + &iio_dev_attr_accel_z.dev_attr.attr, + &iio_dev_attr_thresh_accel_x.dev_attr.attr, + &iio_dev_attr_thresh_accel_y.dev_attr.attr, + &iio_dev_attr_thresh_accel_z.dev_attr.attr, + &iio_dev_attr_available_measurement_modes.dev_attr.attr, + &iio_dev_attr_measurement_mode.dev_attr.attr, + &iio_dev_attr_available_sampling_frequency.dev_attr.attr, + &iio_dev_attr_sampling_frequency.dev_attr.attr, + NULL, +}; + +static struct attribute *sca3000_attributes_with_temp[] = { + &iio_dev_attr_name.dev_attr.attr, + &iio_dev_attr_revision.dev_attr.attr, + &iio_dev_attr_accel_x.dev_attr.attr, + &iio_dev_attr_accel_y.dev_attr.attr, + &iio_dev_attr_accel_z.dev_attr.attr, + &iio_dev_attr_thresh_accel_x.dev_attr.attr, + &iio_dev_attr_thresh_accel_y.dev_attr.attr, + &iio_dev_attr_thresh_accel_z.dev_attr.attr, + &iio_dev_attr_available_measurement_modes.dev_attr.attr, + &iio_dev_attr_measurement_mode.dev_attr.attr, + &iio_dev_attr_available_sampling_frequency.dev_attr.attr, + &iio_dev_attr_sampling_frequency.dev_attr.attr, + /* Only present if temp sensor is */ + &iio_dev_attr_temp.dev_attr.attr, + NULL, +}; + +static const struct attribute_group sca3000_attribute_group = { + .attrs = sca3000_attributes, +}; + +static const struct attribute_group sca3000_attribute_group_with_temp = { + .attrs = sca3000_attributes_with_temp, +}; + +/* RING RELATED interrupt handler */ +/* depending on event, push to the ring buffer event chrdev or the event one */ + +/** + * sca3000_interrupt_handler_bh() - handling ring and non ring events + * + * 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 void sca3000_interrupt_handler_bh(struct work_struct *work_s) +{ + struct sca3000_state *st + = container_of(work_s, struct sca3000_state, + interrupt_handler_ws); + u8 *rx; + int ret; + + /* Could lead if badly timed to an extra read of status reg, + * but ensures no interrupt is missed. + */ + enable_irq(st->us->irq); + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_STATUS, + &rx, 1); + mutex_unlock(&st->lock); + if (ret) + goto done; + + sca3000_ring_int_process(rx[1], st->indio_dev->ring); + + if (rx[1] & SCA3000_INT_STATUS_FREE_FALL) + iio_push_event(st->indio_dev, 0, + IIO_EVENT_CODE_FREE_FALL, + st->last_timestamp); + + if (rx[1] & SCA3000_INT_STATUS_Y_TRIGGER) + iio_push_event(st->indio_dev, 0, + IIO_EVENT_CODE_ACCEL_Y_HIGH, + st->last_timestamp); + + if (rx[1] & SCA3000_INT_STATUS_X_TRIGGER) + iio_push_event(st->indio_dev, 0, + IIO_EVENT_CODE_ACCEL_X_HIGH, + st->last_timestamp); + + if (rx[1] & SCA3000_INT_STATUS_Z_TRIGGER) + iio_push_event(st->indio_dev, 0, + IIO_EVENT_CODE_ACCEL_Z_HIGH, + st->last_timestamp); + +done: + kfree(rx); + return; +} + +/** + * sca3000_handler_th() handles all interrupt events from device + * + * These devices deploy unified interrupt status registers meaning + * all interrupts must be handled together + **/ +static int sca3000_handler_th(struct iio_dev *dev_info, + int index, + s64 timestamp, + int no_test) +{ + struct sca3000_state *st = dev_info->dev_data; + + st->last_timestamp = timestamp; + schedule_work(&st->interrupt_handler_ws); + + return 0; +} + +/** + * sca3000_query_mo_det() is motion detection enabled for this axis + * + * First queries if motion detection is enabled and then if this axis is + * on. + **/ +static ssize_t sca3000_query_mo_det(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + struct iio_event_attr *this_attr = to_iio_event_attr(attr); + int ret, len = 0; + u8 *rx; + u8 protect_mask = 0x03; + + /* read current value of mode register */ + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto error_ret; + + if ((rx[1]&protect_mask) != SCA3000_MEAS_MODE_MOT_DET) + len += sprintf(buf + len, "0\n"); + else { + kfree(rx); + ret = sca3000_read_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + &rx); + if (ret) + goto error_ret; + /* only supporting logical or's for now */ + len += sprintf(buf + len, "%d\n", + (rx[1] & this_attr->mask) ? 1 : 0); + } + kfree(rx); +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} +/** + * sca3000_query_free_fall_mode() is free fall mode enabled + **/ +static ssize_t sca3000_query_free_fall_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + int ret, len; + u8 *rx; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + mutex_unlock(&st->lock); + if (ret) + return ret; + len = sprintf(buf, "%d\n", + !!(rx[1] & SCA3000_FREE_FALL_DETECT)); + kfree(rx); + + return len; +} +/** + * sca3000_query_ring_int() is the hardware ring status interrupt enabled + **/ +static ssize_t sca3000_query_ring_int(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_event_attr *this_attr = to_iio_event_attr(attr); + int ret, len; + u8 *rx; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1); + mutex_unlock(&st->lock); + if (ret) + return ret; + len = sprintf(buf, "%d\n", (rx[1] & this_attr->mask) ? 1 : 0); + kfree(rx); + + return len; +} +/** + * sca3000_set_ring_int() set state of ring status interrupt + **/ +static ssize_t sca3000_set_ring_int(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + struct iio_event_attr *this_attr = to_iio_event_attr(attr); + + long val; + int ret; + u8 *rx; + + mutex_lock(&st->lock); + ret = strict_strtol(buf, 10, &val); + if (ret) + goto error_ret; + ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1); + if (ret) + goto error_ret; + if (val) + ret = sca3000_write_reg(st, + SCA3000_REG_ADDR_INT_MASK, + rx[1] | this_attr->mask); + else + ret = sca3000_write_reg(st, + SCA3000_REG_ADDR_INT_MASK, + rx[1] & ~this_attr->mask); + kfree(rx); +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/** + * sca3000_set_free_fall_mode() simple on off control for free fall int + * + * In these chips the free fall detector should send an interrupt if + * the device falls more than 25cm. This has not been tested due + * to fragile wiring. + **/ + +static ssize_t sca3000_set_free_fall_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + long val; + int ret; + u8 *rx; + u8 protect_mask = SCA3000_FREE_FALL_DETECT; + + mutex_lock(&st->lock); + ret = strict_strtol(buf, 10, &val); + if (ret) + goto error_ret; + + /* read current value of mode register */ + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto error_ret; + + /*if off and should be on*/ + if (val && !(rx[1] & protect_mask)) + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, + (rx[1] | SCA3000_FREE_FALL_DETECT)); + /* if on and should be off */ + else if (!val && (rx[1]&protect_mask)) + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, + (rx[1] & ~protect_mask)); + + kfree(rx); +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/** + * sca3000_set_mo_det() simple on off control for motion detector + * + * 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 ssize_t sca3000_set_mo_det(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct sca3000_state *st = indio_dev->dev_data; + struct iio_event_attr *this_attr = to_iio_event_attr(attr); + long val; + int ret; + u8 *rx; + u8 protect_mask = 0x03; + ret = strict_strtol(buf, 10, &val); + if (ret) + return ret; + + mutex_lock(&st->lock); + /* 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, + &rx); + if (ret) + goto exit_point; + /* Off and should be on */ + if (val && !(rx[1] & this_attr->mask)) { + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + rx[1] | this_attr->mask); + if (ret) + goto exit_point_free_rx; + st->mo_det_use_count++; + } else if (!val && (rx[1]&this_attr->mask)) { + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + rx[1] & ~(this_attr->mask)); + if (ret) + goto exit_point_free_rx; + st->mo_det_use_count--; + } else /* relies on clean state for device on boot */ + goto exit_point_free_rx; + kfree(rx); + /* read current value of mode register */ + ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1); + if (ret) + goto exit_point; + /*if off and should be on*/ + if ((st->mo_det_use_count) + && ((rx[1]&protect_mask) != SCA3000_MEAS_MODE_MOT_DET)) + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, + (rx[1] & ~protect_mask) + | SCA3000_MEAS_MODE_MOT_DET); + /* if on and should be off */ + else if (!(st->mo_det_use_count) + && ((rx[1]&protect_mask) == SCA3000_MEAS_MODE_MOT_DET)) + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, + (rx[1] & ~protect_mask)); +exit_point_free_rx: + kfree(rx); +exit_point: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +/* Shared event handler for all events as single event status register */ +IIO_EVENT_SH(all, &sca3000_handler_th); + +/* Free fall detector related event attribute */ +IIO_EVENT_ATTR_FREE_FALL_DETECT_SH(iio_event_all, + sca3000_query_free_fall_mode, + sca3000_set_free_fall_mode, + 0) + +/* Motion detector related event attributes */ +IIO_EVENT_ATTR_ACCEL_X_HIGH_SH(iio_event_all, + sca3000_query_mo_det, + sca3000_set_mo_det, + SCA3000_MD_CTRL_OR_X); + +IIO_EVENT_ATTR_ACCEL_Y_HIGH_SH(iio_event_all, + sca3000_query_mo_det, + sca3000_set_mo_det, + SCA3000_MD_CTRL_OR_Y); + +IIO_EVENT_ATTR_ACCEL_Z_HIGH_SH(iio_event_all, + sca3000_query_mo_det, + sca3000_set_mo_det, + SCA3000_MD_CTRL_OR_Z); + +/* Hardware ring buffer related event attributes */ +IIO_EVENT_ATTR_RING_50_FULL_SH(iio_event_all, + sca3000_query_ring_int, + sca3000_set_ring_int, + SCA3000_INT_MASK_RING_HALF); + +IIO_EVENT_ATTR_RING_75_FULL_SH(iio_event_all, + sca3000_query_ring_int, + sca3000_set_ring_int, + SCA3000_INT_MASK_RING_THREE_QUARTER); + +static struct attribute *sca3000_event_attributes[] = { + &iio_event_attr_free_fall.dev_attr.attr, + &iio_event_attr_accel_x_high.dev_attr.attr, + &iio_event_attr_accel_y_high.dev_attr.attr, + &iio_event_attr_accel_z_high.dev_attr.attr, + &iio_event_attr_ring_50_full.dev_attr.attr, + &iio_event_attr_ring_75_full.dev_attr.attr, + NULL, +}; + +static struct attribute_group sca3000_event_attribute_group = { + .attrs = sca3000_event_attributes, +}; + +/** + * sca3000_clean_setup() get the device into a predictable state + * + * 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; + u8 *rx; + + mutex_lock(&st->lock); + /* Ensure all interrupts have been acknowledged */ + ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_STATUS, &rx, 1); + if (ret) + goto error_ret; + kfree(rx); + + /* Turn off all motion detection channels */ + ret = sca3000_read_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + &rx); + if (ret) + goto error_ret; + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_MD_CTRL, + rx[1] & SCA3000_MD_CTRL_PROT_MASK); + kfree(rx); + if (ret) + goto error_ret; + + /* Disable ring buffer */ + sca3000_read_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_OUT_CTRL, + &rx); + /* Frequency of ring buffer sampling deliberately restricted to make + * debugging easier - add control of this later */ + ret = sca3000_write_ctrl_reg(st, + SCA3000_REG_CTRL_SEL_OUT_CTRL, + (rx[1] & SCA3000_OUT_CTRL_PROT_MASK) + | SCA3000_OUT_CTRL_BUF_X_EN + | SCA3000_OUT_CTRL_BUF_Y_EN + | SCA3000_OUT_CTRL_BUF_Z_EN + | SCA3000_OUT_CTRL_BUF_DIV_4); + kfree(rx); + + if (ret) + goto error_ret; + /* Enable interrupts, relevant to mode and set up as active low */ + ret = sca3000_read_data(st, + SCA3000_REG_ADDR_INT_MASK, + &rx, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, + SCA3000_REG_ADDR_INT_MASK, + (rx[1] & SCA3000_INT_MASK_PROT_MASK) + | SCA3000_INT_MASK_ACTIVE_LOW); + kfree(rx); + 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(st, + SCA3000_REG_ADDR_MODE, + &rx, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, + SCA3000_REG_ADDR_MODE, + (rx[1] & SCA3000_MODE_PROT_MASK)); + kfree(rx); + st->bpse = 11; + +error_ret: + mutex_unlock(&st->lock); + return ret; +} + +static int __devinit __sca3000_probe(struct spi_device *spi, + enum sca3000_variant variant) +{ + int ret, regdone = 0; + struct sca3000_state *st; + + st = kzalloc(sizeof(struct sca3000_state), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto error_ret; + } + spi_set_drvdata(spi, st); + + st->tx = kmalloc(sizeof(*st->tx)*6, GFP_KERNEL); + if (st->tx == NULL) { + ret = -ENOMEM; + goto error_clear_st; + } + st->rx = kmalloc(sizeof(*st->rx)*3, GFP_KERNEL); + if (st->rx == NULL) { + ret = -ENOMEM; + goto error_free_tx; + } + st->us = spi; + mutex_init(&st->lock); + st->info = &sca3000_spi_chip_info_tbl[variant]; + + st->indio_dev = iio_allocate_device(); + if (st->indio_dev == NULL) { + ret = -ENOMEM; + goto error_free_rx; + } + + st->indio_dev->dev.parent = &spi->dev; + st->indio_dev->num_interrupt_lines = 1; + st->indio_dev->event_attrs = &sca3000_event_attribute_group; + if (st->info->temp_output) + st->indio_dev->attrs = &sca3000_attribute_group_with_temp; + else + st->indio_dev->attrs = &sca3000_attribute_group; + st->indio_dev->dev_data = (void *)(st); + st->indio_dev->modes = INDIO_DIRECT_MODE; + + sca3000_configure_ring(st->indio_dev); + + ret = iio_device_register(st->indio_dev); + if (ret < 0) + goto error_free_dev; + regdone = 1; + ret = iio_ring_buffer_register(st->indio_dev->ring); + if (ret < 0) + goto error_unregister_dev; + if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) { + INIT_WORK(&st->interrupt_handler_ws, + sca3000_interrupt_handler_bh); + ret = iio_register_interrupt_line(spi->irq, + st->indio_dev, + 0, + IRQF_TRIGGER_FALLING, + "sca3000"); + if (ret) + goto error_unregister_ring; + /* RFC + * Probably a common situation. All interrupts need an ack + * and there is only one handler so the complicated list system + * is overkill. At very least a simpler registration method + * might be worthwhile. + */ + iio_add_event_to_list(iio_event_attr_accel_z_high.listel, + &st->indio_dev + ->interrupts[0]->ev_list); + } + sca3000_register_ring_funcs(st->indio_dev); + ret = sca3000_clean_setup(st); + if (ret) + goto error_unregister_interrupt_line; + return 0; + +error_unregister_interrupt_line: + if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) + iio_unregister_interrupt_line(st->indio_dev, 0); +error_unregister_ring: + iio_ring_buffer_unregister(st->indio_dev->ring); +error_unregister_dev: +error_free_dev: + if (regdone) + iio_device_unregister(st->indio_dev); + else + iio_free_device(st->indio_dev); +error_free_rx: + kfree(st->rx); +error_free_tx: + kfree(st->tx); +error_clear_st: + kfree(st); +error_ret: + return ret; +} + +static int sca3000_stop_all_interrupts(struct sca3000_state *st) +{ + int ret; + u8 *rx; + + mutex_lock(&st->lock); + ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1); + if (ret) + goto error_ret; + ret = sca3000_write_reg(st, SCA3000_REG_ADDR_INT_MASK, + (rx[1] & ~(SCA3000_INT_MASK_RING_THREE_QUARTER + | SCA3000_INT_MASK_RING_HALF + | SCA3000_INT_MASK_ALL_INTS))); +error_ret: + kfree(rx); + return ret; + +} + +static int sca3000_remove(struct spi_device *spi) +{ + struct sca3000_state *st = spi_get_drvdata(spi); + struct iio_dev *indio_dev = st->indio_dev; + int ret; + /* Must ensure no interrupts can be generated after this!*/ + ret = sca3000_stop_all_interrupts(st); + if (ret) + return ret; + if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) + iio_unregister_interrupt_line(indio_dev, 0); + iio_ring_buffer_unregister(indio_dev->ring); + sca3000_unconfigure_ring(indio_dev); + iio_device_unregister(indio_dev); + + kfree(st->tx); + kfree(st->rx); + kfree(st); + + return 0; +} + +/* These macros save on an awful lot of repeated code */ +#define SCA3000_VARIANT_PROBE(_name) \ + static int __devinit \ + sca3000_##_name##_probe(struct spi_device *spi) \ + { \ + return __sca3000_probe(spi, _name); \ + } + +#define SCA3000_VARIANT_SPI_DRIVER(_name) \ + struct spi_driver sca3000_##_name##_driver = { \ + .driver = { \ + .name = "sca3000_" #_name, \ + .owner = THIS_MODULE, \ + }, \ + .probe = sca3000_##_name##_probe, \ + .remove = __devexit_p(sca3000_remove), \ + } + +SCA3000_VARIANT_PROBE(d01); +static SCA3000_VARIANT_SPI_DRIVER(d01); + +SCA3000_VARIANT_PROBE(d03); +static SCA3000_VARIANT_SPI_DRIVER(d03); + +SCA3000_VARIANT_PROBE(e02); +static SCA3000_VARIANT_SPI_DRIVER(e02); + +SCA3000_VARIANT_PROBE(e04); +static SCA3000_VARIANT_SPI_DRIVER(e04); + +SCA3000_VARIANT_PROBE(e05); +static SCA3000_VARIANT_SPI_DRIVER(e05); + +SCA3000_VARIANT_PROBE(l01); +static SCA3000_VARIANT_SPI_DRIVER(l01); + +static __init int sca3000_init(void) +{ + int ret; + + ret = spi_register_driver(&sca3000_d01_driver); + if (ret) + goto error_ret; + ret = spi_register_driver(&sca3000_d03_driver); + if (ret) + goto error_unreg_d01; + ret = spi_register_driver(&sca3000_e02_driver); + if (ret) + goto error_unreg_d03; + ret = spi_register_driver(&sca3000_e04_driver); + if (ret) + goto error_unreg_e02; + ret = spi_register_driver(&sca3000_e05_driver); + if (ret) + goto error_unreg_e04; + ret = spi_register_driver(&sca3000_l01_driver); + if (ret) + goto error_unreg_e05; + + return 0; + +error_unreg_e05: + spi_unregister_driver(&sca3000_e05_driver); +error_unreg_e04: + spi_unregister_driver(&sca3000_e04_driver); +error_unreg_e02: + spi_unregister_driver(&sca3000_e02_driver); +error_unreg_d03: + spi_unregister_driver(&sca3000_d03_driver); +error_unreg_d01: + spi_unregister_driver(&sca3000_d01_driver); +error_ret: + + return ret; +} + +static __exit void sca3000_exit(void) +{ + spi_unregister_driver(&sca3000_l01_driver); + spi_unregister_driver(&sca3000_e05_driver); + spi_unregister_driver(&sca3000_e04_driver); + spi_unregister_driver(&sca3000_e02_driver); + spi_unregister_driver(&sca3000_d03_driver); + spi_unregister_driver(&sca3000_d01_driver); +} + +module_init(sca3000_init); +module_exit(sca3000_exit); + +MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>"); +MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver"); +MODULE_LICENSE("GPL v2"); |