diff options
Diffstat (limited to 'drivers/iio/adc/ad7280a.c')
| -rw-r--r-- | drivers/iio/adc/ad7280a.c | 1111 |
1 files changed, 1111 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad7280a.c b/drivers/iio/adc/ad7280a.c new file mode 100644 index 000000000000..ef9d27759961 --- /dev/null +++ b/drivers/iio/adc/ad7280a.c @@ -0,0 +1,1111 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AD7280A Lithium Ion Battery Monitoring System + * + * Copyright 2011 Analog Devices Inc. + */ + +#include <linux/bitfield.h> +#include <linux/bits.h> +#include <linux/crc8.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/spi/spi.h> + +#include <linux/iio/events.h> +#include <linux/iio/iio.h> + +/* Registers */ + +#define AD7280A_CELL_VOLTAGE_1_REG 0x0 /* D11 to D0, Read only */ +#define AD7280A_CELL_VOLTAGE_2_REG 0x1 /* D11 to D0, Read only */ +#define AD7280A_CELL_VOLTAGE_3_REG 0x2 /* D11 to D0, Read only */ +#define AD7280A_CELL_VOLTAGE_4_REG 0x3 /* D11 to D0, Read only */ +#define AD7280A_CELL_VOLTAGE_5_REG 0x4 /* D11 to D0, Read only */ +#define AD7280A_CELL_VOLTAGE_6_REG 0x5 /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_1_REG 0x6 /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_2_REG 0x7 /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_3_REG 0x8 /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_4_REG 0x9 /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_5_REG 0xA /* D11 to D0, Read only */ +#define AD7280A_AUX_ADC_6_REG 0xB /* D11 to D0, Read only */ +#define AD7280A_SELF_TEST_REG 0xC /* D11 to D0, Read only */ + +#define AD7280A_CTRL_HB_REG 0xD /* D15 to D8, Read/write */ +#define AD7280A_CTRL_HB_CONV_INPUT_MSK GENMASK(7, 6) +#define AD7280A_CTRL_HB_CONV_INPUT_ALL 0 +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_5 1 +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL 2 +#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST 3 +#define AD7280A_CTRL_HB_CONV_RREAD_MSK GENMASK(5, 4) +#define AD7280A_CTRL_HB_CONV_RREAD_ALL 0 +#define AD7280A_CTRL_HB_CONV_RREAD_6CELL_AUX1_3_5 1 +#define AD7280A_CTRL_HB_CONV_RREAD_6CELL 2 +#define AD7280A_CTRL_HB_CONV_RREAD_NO 3 +#define AD7280A_CTRL_HB_CONV_START_MSK BIT(3) +#define AD7280A_CTRL_HB_CONV_START_CNVST 0 +#define AD7280A_CTRL_HB_CONV_START_CS 1 +#define AD7280A_CTRL_HB_CONV_AVG_MSK GENMASK(2, 1) +#define AD7280A_CTRL_HB_CONV_AVG_DIS 0 +#define AD7280A_CTRL_HB_CONV_AVG_2 1 +#define AD7280A_CTRL_HB_CONV_AVG_4 2 +#define AD7280A_CTRL_HB_CONV_AVG_8 3 +#define AD7280A_CTRL_HB_PWRDN_SW BIT(0) + +#define AD7280A_CTRL_LB_REG 0xE /* D7 to D0, Read/write */ +#define AD7280A_CTRL_LB_SWRST_MSK BIT(7) +#define AD7280A_CTRL_LB_ACQ_TIME_MSK GENMASK(6, 5) +#define AD7280A_CTRL_LB_ACQ_TIME_400ns 0 +#define AD7280A_CTRL_LB_ACQ_TIME_800ns 1 +#define AD7280A_CTRL_LB_ACQ_TIME_1200ns 2 +#define AD7280A_CTRL_LB_ACQ_TIME_1600ns 3 +#define AD7280A_CTRL_LB_MUST_SET BIT(4) +#define AD7280A_CTRL_LB_THERMISTOR_MSK BIT(3) +#define AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK BIT(2) +#define AD7280A_CTRL_LB_INC_DEV_ADDR_MSK BIT(1) +#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK BIT(0) + +#define AD7280A_CELL_OVERVOLTAGE_REG 0xF /* D7 to D0, Read/write */ +#define AD7280A_CELL_UNDERVOLTAGE_REG 0x10 /* D7 to D0, Read/write */ +#define AD7280A_AUX_ADC_OVERVOLTAGE_REG 0x11 /* D7 to D0, Read/write */ +#define AD7280A_AUX_ADC_UNDERVOLTAGE_REG 0x12 /* D7 to D0, Read/write */ + +#define AD7280A_ALERT_REG 0x13 /* D7 to D0, Read/write */ +#define AD7280A_ALERT_REMOVE_MSK GENMASK(3, 0) +#define AD7280A_ALERT_REMOVE_AUX5 BIT(0) +#define AD7280A_ALERT_REMOVE_AUX3_AUX5 BIT(1) +#define AD7280A_ALERT_REMOVE_VIN5 BIT(2) +#define AD7280A_ALERT_REMOVE_VIN4_VIN5 BIT(3) +#define AD7280A_ALERT_GEN_STATIC_HIGH BIT(6) +#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN (BIT(7) | BIT(6)) + +#define AD7280A_CELL_BALANCE_REG 0x14 /* D7 to D0, Read/write */ +#define AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK GENMASK(7, 2) +#define AD7280A_CB1_TIMER_REG 0x15 /* D7 to D0, Read/write */ +#define AD7280A_CB_TIMER_VAL_MSK GENMASK(7, 3) +#define AD7280A_CB2_TIMER_REG 0x16 /* D7 to D0, Read/write */ +#define AD7280A_CB3_TIMER_REG 0x17 /* D7 to D0, Read/write */ +#define AD7280A_CB4_TIMER_REG 0x18 /* D7 to D0, Read/write */ +#define AD7280A_CB5_TIMER_REG 0x19 /* D7 to D0, Read/write */ +#define AD7280A_CB6_TIMER_REG 0x1A /* D7 to D0, Read/write */ +#define AD7280A_PD_TIMER_REG 0x1B /* D7 to D0, Read/write */ +#define AD7280A_READ_REG 0x1C /* D7 to D0, Read/write */ +#define AD7280A_READ_ADDR_MSK GENMASK(7, 2) +#define AD7280A_CNVST_CTRL_REG 0x1D /* D7 to D0, Read/write */ + +/* Transfer fields */ +#define AD7280A_TRANS_WRITE_DEVADDR_MSK GENMASK(31, 27) +#define AD7280A_TRANS_WRITE_ADDR_MSK GENMASK(26, 21) +#define AD7280A_TRANS_WRITE_VAL_MSK GENMASK(20, 13) +#define AD7280A_TRANS_WRITE_ALL_MSK BIT(12) +#define AD7280A_TRANS_WRITE_CRC_MSK GENMASK(10, 3) +#define AD7280A_TRANS_WRITE_RES_PATTERN 0x2 + +/* Layouts differ for channel vs other registers */ +#define AD7280A_TRANS_READ_DEVADDR_MSK GENMASK(31, 27) +#define AD7280A_TRANS_READ_CONV_CHANADDR_MSK GENMASK(26, 23) +#define AD7280A_TRANS_READ_CONV_DATA_MSK GENMASK(22, 11) +#define AD7280A_TRANS_READ_REG_REGADDR_MSK GENMASK(26, 21) +#define AD7280A_TRANS_READ_REG_DATA_MSK GENMASK(20, 13) +#define AD7280A_TRANS_READ_WRITE_ACK_MSK BIT(10) +#define AD7280A_TRANS_READ_CRC_MSK GENMASK(9, 2) + +/* Magic value used to indicate this special case */ +#define AD7280A_ALL_CELLS (0xAD << 16) + +#define AD7280A_MAX_SPI_CLK_HZ 700000 /* < 1MHz */ +#define AD7280A_MAX_CHAIN 8 +#define AD7280A_CELLS_PER_DEV 6 +#define AD7280A_BITS 12 +#define AD7280A_NUM_CH (AD7280A_AUX_ADC_6_REG - \ + AD7280A_CELL_VOLTAGE_1_REG + 1) + +#define AD7280A_CALC_VOLTAGE_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \ + (c)) +#define AD7280A_CALC_TEMP_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \ + (c) - AD7280A_CELLS_PER_DEV) + +#define AD7280A_DEVADDR_MASTER 0 +#define AD7280A_DEVADDR_ALL 0x1F + +static const unsigned short ad7280a_n_avg[4] = {1, 2, 4, 8}; +static const unsigned short ad7280a_t_acq_ns[4] = {470, 1030, 1510, 1945}; + +/* 5-bit device address is sent LSB first */ +static unsigned int ad7280a_devaddr(unsigned int addr) +{ + return ((addr & 0x1) << 4) | + ((addr & 0x2) << 2) | + (addr & 0x4) | + ((addr & 0x8) >> 2) | + ((addr & 0x10) >> 4); +} + +/* + * During a read a valid write is mandatory. + * So writing to the highest available address (Address 0x1F) and setting the + * address all parts bit to 0 is recommended. + * So the TXVAL is AD7280A_DEVADDR_ALL + CRC + */ +#define AD7280A_READ_TXVAL 0xF800030A + +/* + * AD7280 CRC + * + * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F + */ +#define POLYNOM 0x2F + +struct ad7280_state { + struct spi_device *spi; + struct iio_chan_spec *channels; + unsigned int chain_last_alert_ignore; + bool thermistor_term_en; + int slave_num; + int scan_cnt; + int readback_delay_us; + unsigned char crc_tab[CRC8_TABLE_SIZE]; + u8 oversampling_ratio; + u8 acquisition_time; + unsigned char ctrl_lb; + unsigned char cell_threshhigh; + unsigned char cell_threshlow; + unsigned char aux_threshhigh; + unsigned char aux_threshlow; + unsigned char cb_mask[AD7280A_MAX_CHAIN]; + struct mutex lock; /* protect sensor state */ + + __be32 tx ____cacheline_aligned; + __be32 rx; +}; + +static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned int val) +{ + unsigned char crc; + + crc = crc_tab[val >> 16 & 0xFF]; + crc = crc_tab[crc ^ (val >> 8 & 0xFF)]; + + return crc ^ (val & 0xFF); +} + +static int ad7280_check_crc(struct ad7280_state *st, unsigned int val) +{ + unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10); + + if (crc != ((val >> 2) & 0xFF)) + return -EIO; + + return 0; +} + +/* + * After initiating a conversion sequence we need to wait until the conversion + * is done. The delay is typically in the range of 15..30us however depending on + * the number of devices in the daisy chain, the number of averages taken, + * conversion delays and acquisition time options it may take up to 250us, in + * this case we better sleep instead of busy wait. + */ + +static void ad7280_delay(struct ad7280_state *st) +{ + if (st->readback_delay_us < 50) + udelay(st->readback_delay_us); + else + usleep_range(250, 500); +} + +static int __ad7280_read32(struct ad7280_state *st, unsigned int *val) +{ + int ret; + struct spi_transfer t = { + .tx_buf = &st->tx, + .rx_buf = &st->rx, + .len = sizeof(st->tx), + }; + + st->tx = cpu_to_be32(AD7280A_READ_TXVAL); + + ret = spi_sync_transfer(st->spi, &t, 1); + if (ret) + return ret; + + *val = be32_to_cpu(st->rx); + + return 0; +} + +static int ad7280_write(struct ad7280_state *st, unsigned int devaddr, + unsigned int addr, bool all, unsigned int val) +{ + unsigned int reg = FIELD_PREP(AD7280A_TRANS_WRITE_DEVADDR_MSK, devaddr) | + FIELD_PREP(AD7280A_TRANS_WRITE_ADDR_MSK, addr) | + FIELD_PREP(AD7280A_TRANS_WRITE_VAL_MSK, val) | + FIELD_PREP(AD7280A_TRANS_WRITE_ALL_MSK, all); + + reg |= FIELD_PREP(AD7280A_TRANS_WRITE_CRC_MSK, + ad7280_calc_crc8(st->crc_tab, reg >> 11)); + /* Reserved b010 pattern not included crc calc */ + reg |= AD7280A_TRANS_WRITE_RES_PATTERN; + + st->tx = cpu_to_be32(reg); + + return spi_write(st->spi, &st->tx, sizeof(st->tx)); +} + +static int ad7280_read_reg(struct ad7280_state *st, unsigned int devaddr, + unsigned int addr) +{ + int ret; + unsigned int tmp; + + /* turns off the read operation on all parts */ + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1, + FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK, + AD7280A_CTRL_HB_CONV_INPUT_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK, + AD7280A_CTRL_HB_CONV_RREAD_NO) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, + st->oversampling_ratio)); + if (ret) + return ret; + + /* turns on the read operation on the addressed part */ + ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0, + FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK, + AD7280A_CTRL_HB_CONV_INPUT_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK, + AD7280A_CTRL_HB_CONV_RREAD_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, + st->oversampling_ratio)); + if (ret) + return ret; + + /* Set register address on the part to be read from */ + ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0, + FIELD_PREP(AD7280A_READ_ADDR_MSK, addr)); + if (ret) + return ret; + + ret = __ad7280_read32(st, &tmp); + if (ret) + return ret; + + if (ad7280_check_crc(st, tmp)) + return -EIO; + + if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) || + (FIELD_GET(AD7280A_TRANS_READ_REG_REGADDR_MSK, tmp) != addr)) + return -EFAULT; + + return FIELD_GET(AD7280A_TRANS_READ_REG_DATA_MSK, tmp); +} + +static int ad7280_read_channel(struct ad7280_state *st, unsigned int devaddr, + unsigned int addr) +{ + int ret; + unsigned int tmp; + + ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0, + FIELD_PREP(AD7280A_READ_ADDR_MSK, addr)); + if (ret) + return ret; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1, + FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK, + AD7280A_CTRL_HB_CONV_INPUT_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK, + AD7280A_CTRL_HB_CONV_RREAD_NO) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, + st->oversampling_ratio)); + if (ret) + return ret; + + ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0, + FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK, + AD7280A_CTRL_HB_CONV_INPUT_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK, + AD7280A_CTRL_HB_CONV_RREAD_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK, + AD7280A_CTRL_HB_CONV_START_CS) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, + st->oversampling_ratio)); + if (ret) + return ret; + + ad7280_delay(st); + + ret = __ad7280_read32(st, &tmp); + if (ret) + return ret; + + if (ad7280_check_crc(st, tmp)) + return -EIO; + + if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) || + (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) != addr)) + return -EFAULT; + + return FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp); +} + +static int ad7280_read_all_channels(struct ad7280_state *st, unsigned int cnt, + unsigned int *array) +{ + int i, ret; + unsigned int tmp, sum = 0; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1, + AD7280A_CELL_VOLTAGE_1_REG << 2); + if (ret) + return ret; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1, + FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK, + AD7280A_CTRL_HB_CONV_INPUT_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK, + AD7280A_CTRL_HB_CONV_RREAD_ALL) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK, + AD7280A_CTRL_HB_CONV_START_CS) | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, + st->oversampling_ratio)); + if (ret) + return ret; + + ad7280_delay(st); + + for (i = 0; i < cnt; i++) { + ret = __ad7280_read32(st, &tmp); + if (ret) + return ret; + + if (ad7280_check_crc(st, tmp)) + return -EIO; + + if (array) + array[i] = tmp; + /* only sum cell voltages */ + if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) <= + AD7280A_CELL_VOLTAGE_6_REG) + sum += FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp); + } + + return sum; +} + +static void ad7280_sw_power_down(void *data) +{ + struct ad7280_state *st = data; + + ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1, + AD7280A_CTRL_HB_PWRDN_SW | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio)); +} + +static int ad7280_chain_setup(struct ad7280_state *st) +{ + unsigned int val, n; + int ret; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1, + FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) | + FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) | + AD7280A_CTRL_LB_MUST_SET | + FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 1) | + st->ctrl_lb); + if (ret) + return ret; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1, + FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) | + FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) | + AD7280A_CTRL_LB_MUST_SET | + FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 0) | + st->ctrl_lb); + if (ret) + goto error_power_down; + + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1, + FIELD_PREP(AD7280A_READ_ADDR_MSK, AD7280A_CTRL_LB_REG)); + if (ret) + goto error_power_down; + + for (n = 0; n <= AD7280A_MAX_CHAIN; n++) { + ret = __ad7280_read32(st, &val); + if (ret) + goto error_power_down; + + if (val == 0) + return n - 1; + + if (ad7280_check_crc(st, val)) { + ret = -EIO; + goto error_power_down; + } + + if (n != ad7280a_devaddr(FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, val))) { + ret = -EIO; + goto error_power_down; + } + } + ret = -EFAULT; + +error_power_down: + ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1, + AD7280A_CTRL_HB_PWRDN_SW | + FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio)); + + return ret; +} + +static ssize_t ad7280_show_balance_sw(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, char *buf) +{ + struct ad7280_state *st = iio_priv(indio_dev); + + return sysfs_emit(buf, "%d\n", + !!(st->cb_mask[chan->address >> 8] & + BIT(chan->address & 0xFF))); +} + +static ssize_t ad7280_store_balance_sw(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct ad7280_state *st = iio_priv(indio_dev); + unsigned int devaddr, ch; + bool readin; + int ret; + + ret = strtobool(buf, &readin); + if (ret) + return ret; + + devaddr = chan->address >> 8; + ch = chan->address & 0xFF; + + mutex_lock(&st->lock); + if (readin) + st->cb_mask[devaddr] |= BIT(ch); + else + st->cb_mask[devaddr] &= ~BIT(ch); + + ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE_REG, 0, + FIELD_PREP(AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK, + st->cb_mask[devaddr])); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static ssize_t ad7280_show_balance_timer(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct ad7280_state *st = iio_priv(indio_dev); + unsigned int msecs; + int ret; + + mutex_lock(&st->lock); + ret = ad7280_read_reg(st, chan->address >> 8, + (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG); + mutex_unlock(&st->lock); + + if (ret < 0) + return ret; + + msecs = FIELD_GET(AD7280A_CB_TIMER_VAL_MSK, ret) * 71500; + + return sysfs_emit(buf, "%u.%u\n", msecs / 1000, msecs % 1000); +} + +static ssize_t ad7280_store_balance_timer(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct ad7280_state *st = iio_priv(indio_dev); + int val, val2; + int ret; + + ret = iio_str_to_fixpoint(buf, 1000, &val, &val2); + if (ret) + return ret; + + val = val * 1000 + val2; + val /= 71500; + + if (val > 31) + return -EINVAL; + + mutex_lock(&st->lock); + ret = ad7280_write(st, chan->address >> 8, + (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG, 0, + FIELD_PREP(AD7280A_CB_TIMER_VAL_MSK, val)); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static const struct iio_chan_spec_ext_info ad7280_cell_ext_info[] = { + { + .name = "balance_switch_en", + .read = ad7280_show_balance_sw, + .write = ad7280_store_balance_sw, + .shared = IIO_SEPARATE, + }, { + .name = "balance_switch_timer", + .read = ad7280_show_balance_timer, + .write = ad7280_store_balance_timer, + .shared = IIO_SEPARATE, + }, + {} +}; + +static const struct iio_event_spec ad7280_events[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_FALLING, + .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE), + }, +}; + +static void ad7280_voltage_channel_init(struct iio_chan_spec *chan, int i, + bool irq_present) +{ + chan->type = IIO_VOLTAGE; + chan->differential = 1; + chan->channel = i; + chan->channel2 = chan->channel + 1; + if (irq_present) { + chan->event_spec = ad7280_events; + chan->num_event_specs = ARRAY_SIZE(ad7280_events); + } + chan->ext_info = ad7280_cell_ext_info; +} + +static void ad7280_temp_channel_init(struct iio_chan_spec *chan, int i, + bool irq_present) +{ + chan->type = IIO_TEMP; + chan->channel = i; + if (irq_present) { + chan->event_spec = ad7280_events; + chan->num_event_specs = ARRAY_SIZE(ad7280_events); + } +} + +static void ad7280_common_fields_init(struct iio_chan_spec *chan, int addr, + int cnt) +{ + chan->indexed = 1; + chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE); + chan->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO); + chan->address = addr; + chan->scan_index = cnt; + chan->scan_type.sign = 'u'; + chan->scan_type.realbits = 12; + chan->scan_type.storagebits = 32; +} + +static void ad7280_total_voltage_channel_init(struct iio_chan_spec *chan, + int cnt, int dev) +{ + chan->type = IIO_VOLTAGE; + chan->differential = 1; + chan->channel = 0; + chan->channel2 = dev * AD7280A_CELLS_PER_DEV; + chan->address = AD7280A_ALL_CELLS; + chan->indexed = 1; + chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE); + chan->scan_index = cnt; + chan->scan_type.sign = 'u'; + chan->scan_type.realbits = 32; + chan->scan_type.storagebits = 32; +} + +static void ad7280_init_dev_channels(struct ad7280_state *st, int dev, int *cnt, + bool irq_present) +{ + int addr, ch, i; + struct iio_chan_spec *chan; + + for (ch = AD7280A_CELL_VOLTAGE_1_REG; ch <= AD7280A_AUX_ADC_6_REG; ch++) { + chan = &st->channels[*cnt]; + + if (ch < AD7280A_AUX_ADC_1_REG) { + i = AD7280A_CALC_VOLTAGE_CHAN_NUM(dev, ch); + ad7280_voltage_channel_init(chan, i, irq_present); + } else { + i = AD7280A_CALC_TEMP_CHAN_NUM(dev, ch); + ad7280_temp_channel_init(chan, i, irq_present); + } + + addr = ad7280a_devaddr(dev) << 8 | ch; + ad7280_common_fields_init(chan, addr, *cnt); + + (*cnt)++; + } +} + +static int ad7280_channel_init(struct ad7280_state *st, bool irq_present) +{ + int dev, cnt = 0; + + st->channels = devm_kcalloc(&st->spi->dev, (st->slave_num + 1) * 12 + 1, + sizeof(*st->channels), GFP_KERNEL); + if (!st->channels) + return -ENOMEM; + + for (dev = 0; dev <= st->slave_num; dev++) + ad7280_init_dev_channels(st, dev, &cnt, irq_present); + + ad7280_total_voltage_channel_init(&st->channels[cnt], cnt, dev); + + return cnt + 1; +} + +static int ad7280a_read_thresh(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 ad7280_state *st = iio_priv(indio_dev); + + switch (chan->type) { + case IIO_VOLTAGE: + switch (dir) { + case IIO_EV_DIR_RISING: + *val = 1000 + (st->cell_threshhigh * 1568L) / 100; + return IIO_VAL_INT; + case IIO_EV_DIR_FALLING: + *val = 1000 + (st->cell_threshlow * 1568L) / 100; + return IIO_VAL_INT; + default: + return -EINVAL; + } + break; + case IIO_TEMP: + switch (dir) { + case IIO_EV_DIR_RISING: + *val = ((st->aux_threshhigh) * 196L) / 10; + return IIO_VAL_INT; + case IIO_EV_DIR_FALLING: + *val = (st->aux_threshlow * 196L) / 10; + return IIO_VAL_INT; + default: + return -EINVAL; + } + break; + default: + return -EINVAL; + } +} + +static int ad7280a_write_thresh(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 ad7280_state *st = iio_priv(indio_dev); + unsigned int addr; + long value; + int ret; + + if (val2 != 0) + return -EINVAL; + + mutex_lock(&st->lock); + switch (chan->type) { + case IIO_VOLTAGE: + value = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */ + value = clamp(value, 0L, 0xFFL); + switch (dir) { + case IIO_EV_DIR_RISING: + addr = AD7280A_CELL_OVERVOLTAGE_REG; + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr, + 1, val); + if (ret) + break; + st->cell_threshhigh = value; + break; + case IIO_EV_DIR_FALLING: + addr = AD7280A_CELL_UNDERVOLTAGE_REG; + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr, + 1, val); + if (ret) + break; + st->cell_threshlow = value; + break; + default: + ret = -EINVAL; + goto err_unlock; + } + break; + case IIO_TEMP: + value = (val * 10) / 196; /* LSB 19.6mV */ + value = clamp(value, 0L, 0xFFL); + switch (dir) { + case IIO_EV_DIR_RISING: + addr = AD7280A_AUX_ADC_OVERVOLTAGE_REG; + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr, + 1, val); + if (ret) + break; + st->aux_threshhigh = val; + break; + case IIO_EV_DIR_FALLING: + addr = AD7280A_AUX_ADC_UNDERVOLTAGE_REG; + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr, + 1, val); + if (ret) + break; + st->aux_threshlow = val; + break; + default: + ret = -EINVAL; + goto err_unlock; + } + break; + default: + ret = -EINVAL; + goto err_unlock; + } + +err_unlock: + mutex_unlock(&st->lock); + + return ret; +} + +static irqreturn_t ad7280_event_handler(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct ad7280_state *st = iio_priv(indio_dev); + unsigned int *channels; + int i, ret; + + channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL); + if (!channels) + return IRQ_HANDLED; + + ret = ad7280_read_all_channels(st, st->scan_cnt, channels); + if (ret < 0) + goto out; + + for (i = 0; i < st->scan_cnt; i++) { + unsigned int val; + + val = FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, channels[i]); + if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, channels[i]) <= + AD7280A_CELL_VOLTAGE_6_REG) { + if (val >= st->cell_threshhigh) { + u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0, + IIO_EV_DIR_RISING, + IIO_EV_TYPE_THRESH, + 0, 0, 0); + iio_push_event(indio_dev, tmp, + iio_get_time_ns(indio_dev)); + } else if (val <= st->cell_threshlow) { + u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0, + IIO_EV_DIR_FALLING, + IIO_EV_TYPE_THRESH, + 0, 0, 0); + iio_push_event(indio_dev, tmp, + iio_get_time_ns(indio_dev)); + } + } else { + if (val >= st->aux_threshhigh) { + u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0, + IIO_EV_TYPE_THRESH, + IIO_EV_DIR_RISING); + iio_push_event(indio_dev, tmp, + iio_get_time_ns(indio_dev)); + } else if (val <= st->aux_threshlow) { + u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0, + IIO_EV_TYPE_THRESH, + IIO_EV_DIR_FALLING); + iio_push_event(indio_dev, tmp, + iio_get_time_ns(indio_dev)); + } + } + } + +out: + kfree(channels); + + return IRQ_HANDLED; +} + +static void ad7280_update_delay(struct ad7280_state *st) +{ + /* + * Total Conversion Time = ((tACQ + tCONV) * + * (Number of Conversions per Part)) − + * tACQ + ((N - 1) * tDELAY) + * + * Readback Delay = Total Conversion Time + tWAIT + */ + + st->readback_delay_us = + ((ad7280a_t_acq_ns[st->acquisition_time & 0x3] + 720) * + (AD7280A_NUM_CH * ad7280a_n_avg[st->oversampling_ratio & 0x3])) - + ad7280a_t_acq_ns[st->acquisition_time & 0x3] + st->slave_num * 250; + + /* Convert to usecs */ + st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000); + st->readback_delay_us += 5; /* Add tWAIT */ +} + +static int ad7280_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct ad7280_state *st = iio_priv(indio_dev); + int ret; + + switch (m) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + if (chan->address == AD7280A_ALL_CELLS) + ret = ad7280_read_all_channels(st, st->scan_cnt, NULL); + else + ret = ad7280_read_channel(st, chan->address >> 8, + chan->address & 0xFF); + mutex_unlock(&st->lock); + + if (ret < 0) + return ret; + + *val = ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6_REG) + *val = 4000; + else + *val = 5000; + + *val2 = AD7280A_BITS; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = ad7280a_n_avg[st->oversampling_ratio]; + return IIO_VAL_INT; + } + return -EINVAL; +} + +static int ad7280_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct ad7280_state *st = iio_priv(indio_dev); + int i; + + switch (mask) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + if (val2 != 0) + return -EINVAL; + for (i = 0; i < ARRAY_SIZE(ad7280a_n_avg); i++) { + if (val == ad7280a_n_avg[i]) { + st->oversampling_ratio = i; + ad7280_update_delay(st); + return 0; + } + } + return -EINVAL; + default: + return -EINVAL; + } +} + +static const struct iio_info ad7280_info = { + .read_raw = ad7280_read_raw, + .write_raw = ad7280_write_raw, + .read_event_value = &ad7280a_read_thresh, + .write_event_value = &ad7280a_write_thresh, +}; + +static const struct iio_info ad7280_info_no_irq = { + .read_raw = ad7280_read_raw, + .write_raw = ad7280_write_raw, +}; + +static int ad7280_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct ad7280_state *st; + int ret; + struct iio_dev *indio_dev; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + st->spi = spi; + mutex_init(&st->lock); + + st->thermistor_term_en = + device_property_read_bool(dev, "adi,thermistor-termination"); + + if (device_property_present(dev, "adi,acquisition-time-ns")) { + u32 val; + + ret = device_property_read_u32(dev, "adi,acquisition-time-ns", &val); + if (ret) + return ret; + + switch (val) { + case 400: + st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns; + break; + case 800: + st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_800ns; + break; + case 1200: + st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1200ns; + break; + case 1600: + st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1600ns; + break; + default: + dev_err(dev, "Firmware provided acquisition time is invalid\n"); + return -EINVAL; + } + } else { + st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns; + } + + /* Alert masks are intended for when particular inputs are not wired up */ + if (device_property_present(dev, "adi,voltage-alert-last-chan")) { + u32 val; + + ret = device_property_read_u32(dev, "adi,voltage-alert-last-chan", &val); + if (ret) + return ret; + + switch (val) { + case 3: + st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN4_VIN5; + break; + case 4: + st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN5; + break; + case 5: + break; + default: + dev_err(dev, + "Firmware provided last voltage alert channel invalid\n"); + break; + } + } + crc8_populate_msb(st->crc_tab, POLYNOM); + + st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_HZ; + st->spi->mode = SPI_MODE_1; + spi_setup(st->spi); + + st->ctrl_lb = FIELD_PREP(AD7280A_CTRL_LB_ACQ_TIME_MSK, st->acquisition_time) | + FIELD_PREP(AD7280A_CTRL_LB_THERMISTOR_MSK, st->thermistor_term_en); + st->oversampling_ratio = 0; /* No oversampling */ + + ret = ad7280_chain_setup(st); + if (ret < 0) + return ret; + + st->slave_num = ret; + st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH; + st->cell_threshhigh = 0xFF; + st->aux_threshhigh = 0xFF; + + ret = devm_add_action_or_reset(dev, ad7280_sw_power_down, st); + if (ret) + return ret; + + ad7280_update_delay(st); + + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = ad7280_channel_init(st, spi->irq > 0); + if (ret < 0) + return ret; + + indio_dev->num_channels = ret; + indio_dev->channels = st->channels; + if (spi->irq > 0) { + ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, + AD7280A_ALERT_REG, 1, + AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN); + if (ret) + return ret; + + ret = ad7280_write(st, ad7280a_devaddr(st->slave_num), + AD7280A_ALERT_REG, 0, + AD7280A_ALERT_GEN_STATIC_HIGH | + FIELD_PREP(AD7280A_ALERT_REMOVE_MSK, + st->chain_last_alert_ignore)); + if (ret) + return ret; + + ret = devm_request_threaded_irq(dev, spi->irq, + NULL, + ad7280_event_handler, + IRQF_TRIGGER_FALLING | + IRQF_ONESHOT, + indio_dev->name, + indio_dev); + if (ret) + return ret; + + indio_dev->info = &ad7280_info; + } else { + indio_dev->info = &ad7280_info_no_irq; + } + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct spi_device_id ad7280_id[] = { + {"ad7280a", 0}, + {} +}; +MODULE_DEVICE_TABLE(spi, ad7280_id); + +static struct spi_driver ad7280_driver = { + .driver = { + .name = "ad7280", + }, + .probe = ad7280_probe, + .id_table = ad7280_id, +}; +module_spi_driver(ad7280_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Analog Devices AD7280A"); +MODULE_LICENSE("GPL v2"); |