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-rw-r--r--drivers/iio/adc/ad7280a.c1111
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 0000000000..d4a4e15c82
--- /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 __aligned(IIO_DMA_MINALIGN);
+ __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 = kstrtobool(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, value);
+ 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, value);
+ 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, value);
+ if (ret)
+ break;
+ st->aux_threshhigh = value;
+ break;
+ case IIO_EV_DIR_FALLING:
+ addr = AD7280A_AUX_ADC_UNDERVOLTAGE_REG;
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
+ 1, value);
+ if (ret)
+ break;
+ st->aux_threshlow = value;
+ 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");