--- /dev/null
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7280a.h"
+
+/* Registers */
+#define AD7280A_CELL_VOLTAGE_1 0x0 /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_2 0x1 /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_3 0x2 /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_4 0x3 /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_5 0x4 /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_6 0x5 /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_1 0x6 /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_2 0x7 /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_3 0x8 /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_4 0x9 /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_5 0xA /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_6 0xB /* D11 to D0, Read only */
+#define AD7280A_SELF_TEST 0xC /* D11 to D0, Read only */
+#define AD7280A_CONTROL_HB 0xD /* D15 to D8, Read/write */
+#define AD7280A_CONTROL_LB 0xE /* D7 to D0, Read/write */
+#define AD7280A_CELL_OVERVOLTAGE 0xF /* D7 to D0, Read/write */
+#define AD7280A_CELL_UNDERVOLTAGE 0x10 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_OVERVOLTAGE 0x11 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_UNDERVOLTAGE 0x12 /* D7 to D0, Read/write */
+#define AD7280A_ALERT 0x13 /* D7 to D0, Read/write */
+#define AD7280A_CELL_BALANCE 0x14 /* D7 to D0, Read/write */
+#define AD7280A_CB1_TIMER 0x15 /* D7 to D0, Read/write */
+#define AD7280A_CB2_TIMER 0x16 /* D7 to D0, Read/write */
+#define AD7280A_CB3_TIMER 0x17 /* D7 to D0, Read/write */
+#define AD7280A_CB4_TIMER 0x18 /* D7 to D0, Read/write */
+#define AD7280A_CB5_TIMER 0x19 /* D7 to D0, Read/write */
+#define AD7280A_CB6_TIMER 0x1A /* D7 to D0, Read/write */
+#define AD7280A_PD_TIMER 0x1B /* D7 to D0, Read/write */
+#define AD7280A_READ 0x1C /* D7 to D0, Read/write */
+#define AD7280A_CNVST_CONTROL 0x1D /* D7 to D0, Read/write */
+
+/* Bits and Masks */
+#define AD7280A_CTRL_HB_CONV_INPUT_ALL (0 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4 (1 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL (2 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST (3 << 6)
+#define AD7280A_CTRL_HB_CONV_RES_READ_ALL (0 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4 (1 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL (2 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_NO (3 << 4)
+#define AD7280A_CTRL_HB_CONV_START_CNVST (0 << 3)
+#define AD7280A_CTRL_HB_CONV_START_CS (1 << 3)
+#define AD7280A_CTRL_HB_CONV_AVG_DIS (0 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_2 (1 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_4 (2 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_8 (3 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG(x) ((x) << 1)
+#define AD7280A_CTRL_HB_PWRDN_SW (1 << 0)
+
+#define AD7280A_CTRL_LB_SWRST (1 << 7)
+#define AD7280A_CTRL_LB_ACQ_TIME_400ns (0 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_800ns (1 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1200ns (2 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1600ns (3 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME(x) ((x) << 5)
+#define AD7280A_CTRL_LB_MUST_SET (1 << 4)
+#define AD7280A_CTRL_LB_THERMISTOR_EN (1 << 3)
+#define AD7280A_CTRL_LB_LOCK_DEV_ADDR (1 << 2)
+#define AD7280A_CTRL_LB_INC_DEV_ADDR (1 << 1)
+#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN (1 << 0)
+
+#define AD7280A_ALERT_GEN_STATIC_HIGH (1 << 6)
+#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN (3 << 6)
+
+#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 - \
+ AD7280A_CELL_VOLTAGE_1 + 1)
+
+#define AD7280A_DEVADDR_MASTER 0
+#define AD7280A_DEVADDR_ALL 0x1F
+/* 5-bit device address is sent LSB first */
+#define AD7280A_DEVADDR(addr) (((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
+ (addr & 0x4) | ((addr & 0x8) >> 3) | \
+ ((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
+#define POLYNOM_ORDER 8
+#define HIGHBIT 1 << (POLYNOM_ORDER - 1);
+
+struct ad7280_state {
+ struct spi_device *spi;
+ struct iio_chan_spec *channels;
+ struct iio_dev_attr *iio_attr;
+ int slave_num;
+ int scan_cnt;
+ int readback_delay_us;
+ unsigned char crc_tab[256];
+ unsigned char ctrl_hb;
+ 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];
+};
+
+static void ad7280_crc8_build_table(unsigned char *crc_tab)
+{
+ unsigned char bit, crc;
+ int cnt, i;
+
+ for (cnt = 0; cnt < 256; cnt++) {
+ crc = cnt;
+ for (i = 0; i < 8; i++) {
+ bit = crc & HIGHBIT;
+ crc <<= 1;
+ if (bit)
+ crc ^= POLYNOM;
+ }
+ crc_tab[cnt] = crc;
+ }
+}
+
+static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned 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 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..30 us
+ * however depending an the number of devices in the daisy chain and 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
+ msleep(1);
+}
+
+static int __ad7280_read32(struct spi_device *spi, unsigned *val)
+{
+ unsigned rx_buf, tx_buf = cpu_to_be32(AD7280A_READ_TXVAL);
+ int ret;
+
+ struct spi_transfer t = {
+ .tx_buf = &tx_buf,
+ .rx_buf = &rx_buf,
+ .len = 4,
+ };
+ struct spi_message m;
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+
+ ret = spi_sync(spi, &m);
+ if (ret)
+ return ret;
+
+ *val = be32_to_cpu(rx_buf);
+
+ return 0;
+}
+
+static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
+ unsigned addr, bool all, unsigned val)
+{
+ unsigned reg = (devaddr << 27 | addr << 21 |
+ (val & 0xFF) << 13 | all << 12);
+
+ reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
+ reg = cpu_to_be32(reg);
+
+ return spi_write(st->spi, ®, 4);
+}
+
+static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
+ unsigned addr)
+{
+ int ret;
+ unsigned tmp;
+
+ /* turns off the read operation on all parts */
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+ AD7280A_CTRL_HB_CONV_INPUT_ALL |
+ AD7280A_CTRL_HB_CONV_RES_READ_NO |
+ st->ctrl_hb);
+ if (ret)
+ return ret;
+
+ /* turns on the read operation on the addressed part */
+ ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+ AD7280A_CTRL_HB_CONV_INPUT_ALL |
+ AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+ st->ctrl_hb);
+ if (ret)
+ return ret;
+
+ /* Set register address on the part to be read from */
+ ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+ if (ret)
+ return ret;
+
+ __ad7280_read32(st->spi, &tmp);
+
+ if (ad7280_check_crc(st, tmp))
+ return -EIO;
+
+ if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
+ return -EFAULT;
+
+ return (tmp >> 13) & 0xFF;
+}
+
+static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
+ unsigned addr)
+{
+ int ret;
+ unsigned tmp;
+
+ ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+ if (ret)
+ return ret;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+ AD7280A_CTRL_HB_CONV_INPUT_ALL |
+ AD7280A_CTRL_HB_CONV_RES_READ_NO |
+ st->ctrl_hb);
+ if (ret)
+ return ret;
+
+ ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+ AD7280A_CTRL_HB_CONV_INPUT_ALL |
+ AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+ AD7280A_CTRL_HB_CONV_START_CS |
+ st->ctrl_hb);
+ if (ret)
+ return ret;
+
+ ad7280_delay(st);
+
+ __ad7280_read32(st->spi, &tmp);
+
+ if (ad7280_check_crc(st, tmp))
+ return -EIO;
+
+ if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
+ return -EFAULT;
+
+ return (tmp >> 11) & 0xFFF;
+}
+
+static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
+ unsigned *array)
+{
+ int i, ret;
+ unsigned tmp, sum = 0;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+ AD7280A_CELL_VOLTAGE_1 << 2);
+ if (ret)
+ return ret;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+ AD7280A_CTRL_HB_CONV_INPUT_ALL |
+ AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+ AD7280A_CTRL_HB_CONV_START_CS |
+ st->ctrl_hb);
+ if (ret)
+ return ret;
+
+ ad7280_delay(st);
+
+ for (i = 0; i < cnt; i++) {
+ __ad7280_read32(st->spi, &tmp);
+
+ if (ad7280_check_crc(st, tmp))
+ return -EIO;
+
+ if (array)
+ array[i] = tmp;
+ /* only sum cell voltages */
+ if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
+ sum += ((tmp >> 11) & 0xFFF);
+ }
+
+ return sum;
+}
+
+static int ad7280_chain_setup(struct ad7280_state *st)
+{
+ unsigned val, n;
+ int ret;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+ AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+ AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+ AD7280A_CTRL_LB_MUST_SET |
+ AD7280A_CTRL_LB_SWRST |
+ st->ctrl_lb);
+ if (ret)
+ return ret;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+ AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+ AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+ AD7280A_CTRL_LB_MUST_SET |
+ st->ctrl_lb);
+ if (ret)
+ return ret;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+ AD7280A_CONTROL_LB << 2);
+ if (ret)
+ return ret;
+
+ for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
+ __ad7280_read32(st->spi, &val);
+ if (val == 0)
+ return n - 1;
+
+ if (ad7280_check_crc(st, val))
+ return -EIO;
+
+ if (n != AD7280A_DEVADDR(val >> 27))
+ return -EIO;
+ }
+
+ return -EFAULT;
+}
+
+static ssize_t ad7280_show_balance_sw(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+ return sprintf(buf, "%d\n",
+ !!(st->cb_mask[this_attr->address >> 8] &
+ (1 << ((this_attr->address & 0xFF) + 2))));
+}
+
+static ssize_t ad7280_store_balance_sw(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ bool readin;
+ int ret;
+ unsigned devaddr, ch;
+
+ ret = strtobool(buf, &readin);
+ if (ret)
+ return ret;
+
+ devaddr = this_attr->address >> 8;
+ ch = this_attr->address & 0xFF;
+
+ mutex_lock(&dev_info->mlock);
+ if (readin)
+ st->cb_mask[devaddr] |= 1 << (ch + 2);
+ else
+ st->cb_mask[devaddr] &= ~(1 << (ch + 2));
+
+ ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
+ 0, st->cb_mask[devaddr]);
+ mutex_unlock(&dev_info->mlock);
+
+ return ret ? ret : len;
+}
+
+static ssize_t ad7280_show_balance_timer(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int ret;
+ unsigned msecs;
+
+ mutex_lock(&dev_info->mlock);
+ ret = ad7280_read(st, this_attr->address >> 8,
+ this_attr->address & 0xFF);
+ mutex_unlock(&dev_info->mlock);
+
+ if (ret < 0)
+ return ret;
+
+ msecs = (ret >> 3) * 71500;
+
+ return sprintf(buf, "%d\n", msecs);
+}
+
+static ssize_t ad7280_store_balance_timer(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ long val;
+ int ret;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ val /= 71500;
+
+ if (val > 31)
+ return -EINVAL;
+
+ mutex_lock(&dev_info->mlock);
+ ret = ad7280_write(st, this_attr->address >> 8,
+ this_attr->address & 0xFF,
+ 0, (val & 0x1F) << 3);
+ mutex_unlock(&dev_info->mlock);
+
+ return ret ? ret : len;
+}
+
+static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
+ AD7280A_CELLS_PER_DEV * 2 + 1];
+
+static struct attribute_group ad7280_attrs_group = {
+ .attrs = ad7280_attributes,
+};
+
+static int ad7280_channel_init(struct ad7280_state *st)
+{
+ int dev, ch, cnt;
+
+ st->channels = kzalloc(sizeof(*st->channels) *
+ ((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
+ if (st->channels == NULL)
+ return -ENOMEM;
+
+ for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+ for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
+ cnt++) {
+ if (ch < AD7280A_AUX_ADC_1) {
+ st->channels[cnt].type = IIO_IN_DIFF;
+ st->channels[cnt].channel = (dev * 6) + ch;
+ st->channels[cnt].channel2 =
+ st->channels[cnt].channel + 1;
+ } else {
+ st->channels[cnt].type = IIO_TEMP;
+ st->channels[cnt].channel = (dev * 6) + ch - 6;
+ }
+ st->channels[cnt].indexed = 1;
+ st->channels[cnt].info_mask =
+ (1 << IIO_CHAN_INFO_SCALE_SHARED);
+ st->channels[cnt].address =
+ AD7280A_DEVADDR(dev) << 8 | ch;
+ st->channels[cnt].scan_index = cnt;
+ st->channels[cnt].scan_type.sign = 'u';
+ st->channels[cnt].scan_type.realbits = 12;
+ st->channels[cnt].scan_type.storagebits = 32;
+ st->channels[cnt].scan_type.shift = 0;
+ }
+
+ st->channels[cnt].type = IIO_IN_DIFF;
+ st->channels[cnt].channel = 0;
+ st->channels[cnt].channel2 = dev * 6;
+ st->channels[cnt].address = AD7280A_ALL_CELLS;
+ st->channels[cnt].indexed = 1;
+ st->channels[cnt].info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED);
+ st->channels[cnt].scan_index = cnt;
+ st->channels[cnt].scan_type.sign = 'u';
+ st->channels[cnt].scan_type.realbits = 32;
+ st->channels[cnt].scan_type.storagebits = 32;
+ st->channels[cnt].scan_type.shift = 0;
+ cnt++;
+ st->channels[cnt].type = IIO_TIMESTAMP;
+ st->channels[cnt].channel = -1;
+ st->channels[cnt].scan_index = cnt;
+ st->channels[cnt].scan_type.sign = 's';
+ st->channels[cnt].scan_type.realbits = 64;
+ st->channels[cnt].scan_type.storagebits = 64;
+ st->channels[cnt].scan_type.shift = 0;
+
+ return cnt + 1;
+}
+
+static int ad7280_attr_init(struct ad7280_state *st)
+{
+ int dev, ch, cnt;
+
+ st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
+ AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
+ if (st->iio_attr == NULL)
+ return -ENOMEM;
+
+ for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+ for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
+ ch++, cnt++) {
+ st->iio_attr[cnt].address =
+ AD7280A_DEVADDR(dev) << 8 | ch;
+ st->iio_attr[cnt].dev_attr.attr.mode =
+ S_IWUSR | S_IRUGO;
+ st->iio_attr[cnt].dev_attr.show =
+ ad7280_show_balance_sw;
+ st->iio_attr[cnt].dev_attr.store =
+ ad7280_store_balance_sw;
+ st->iio_attr[cnt].dev_attr.attr.name =
+ kasprintf(GFP_KERNEL,
+ "in%d-in%d_balance_switch_en",
+ (dev * AD7280A_CELLS_PER_DEV) + ch,
+ (dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+ ad7280_attributes[cnt] =
+ &st->iio_attr[cnt].dev_attr.attr;
+ cnt++;
+ st->iio_attr[cnt].address =
+ AD7280A_DEVADDR(dev) << 8 |
+ (AD7280A_CB1_TIMER + ch);
+ st->iio_attr[cnt].dev_attr.attr.mode =
+ S_IWUSR | S_IRUGO;
+ st->iio_attr[cnt].dev_attr.show =
+ ad7280_show_balance_timer;
+ st->iio_attr[cnt].dev_attr.store =
+ ad7280_store_balance_timer;
+ st->iio_attr[cnt].dev_attr.attr.name =
+ kasprintf(GFP_KERNEL, "in%d-in%d_balance_timer",
+ (dev * AD7280A_CELLS_PER_DEV) + ch,
+ (dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+ ad7280_attributes[cnt] =
+ &st->iio_attr[cnt].dev_attr.attr;
+ }
+
+ ad7280_attributes[cnt] = NULL;
+
+ return 0;
+}
+
+static ssize_t ad7280_read_channel_config(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ unsigned val;
+
+ switch (this_attr->address) {
+ case AD7280A_CELL_OVERVOLTAGE:
+ val = 1000 + (st->cell_threshhigh * 1568) / 100;
+ break;
+ case AD7280A_CELL_UNDERVOLTAGE:
+ val = 1000 + (st->cell_threshlow * 1568) / 100;
+ break;
+ case AD7280A_AUX_ADC_OVERVOLTAGE:
+ val = (st->aux_threshhigh * 196) / 10;
+ break;
+ case AD7280A_AUX_ADC_UNDERVOLTAGE:
+ val = (st->aux_threshlow * 196) / 10;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t ad7280_write_channel_config(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7280_state *st = iio_priv(dev_info);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+ long val;
+ int ret;
+
+ ret = strict_strtol(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ switch (this_attr->address) {
+ case AD7280A_CELL_OVERVOLTAGE:
+ case AD7280A_CELL_UNDERVOLTAGE:
+ val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
+ break;
+ case AD7280A_AUX_ADC_OVERVOLTAGE:
+ case AD7280A_AUX_ADC_UNDERVOLTAGE:
+ val = (val * 10) / 196; /* LSB 19.6mV */
+ break;
+ default:
+ return -EFAULT;
+ }
+
+ val = clamp(val, 0L, 0xFFL);
+
+ mutex_lock(&dev_info->mlock);
+ switch (this_attr->address) {
+ case AD7280A_CELL_OVERVOLTAGE:
+ st->cell_threshhigh = val;
+ break;
+ case AD7280A_CELL_UNDERVOLTAGE:
+ st->cell_threshlow = val;
+ break;
+ case AD7280A_AUX_ADC_OVERVOLTAGE:
+ st->aux_threshhigh = val;
+ break;
+ case AD7280A_AUX_ADC_UNDERVOLTAGE:
+ st->aux_threshlow = val;
+ break;
+ }
+
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+ this_attr->address, 1, val);
+
+ mutex_unlock(&dev_info->mlock);
+
+ return ret ? ret : len;
+}
+
+static irqreturn_t ad7280_event_handler(int irq, void *private)
+{
+ struct iio_dev *dev_info = private;
+ struct ad7280_state *st = iio_priv(dev_info);
+ unsigned *channels;
+ int i, ret;
+
+ channels = kzalloc(sizeof(*channels) * st->scan_cnt, GFP_KERNEL);
+ if (channels == NULL)
+ return IRQ_HANDLED;
+
+ ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
+ if (ret < 0)
+ return IRQ_HANDLED;
+
+ for (i = 0; i < st->scan_cnt; i++) {
+ if (((channels[i] >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6) {
+ if (((channels[i] >> 11) & 0xFFF) >=
+ st->cell_threshhigh)
+ iio_push_event(dev_info, 0,
+ IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+ 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ iio_get_time_ns());
+ else if (((channels[i] >> 11) & 0xFFF) <=
+ st->cell_threshlow)
+ iio_push_event(dev_info, 0,
+ IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+ 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_FALLING),
+ iio_get_time_ns());
+ } else {
+ if (((channels[i] >> 11) & 0xFFF) >= st->aux_threshhigh)
+ iio_push_event(dev_info, 0,
+ IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+ 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ iio_get_time_ns());
+ else if (((channels[i] >> 11) & 0xFFF) <=
+ st->aux_threshlow)
+ iio_push_event(dev_info, 0,
+ IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+ 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_FALLING),
+ iio_get_time_ns());
+ }
+ }
+
+ kfree(channels);
+
+ return IRQ_HANDLED;
+}
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_low_value,
+ in-in_thresh_low_value,
+ S_IRUGO | S_IWUSR,
+ ad7280_read_channel_config,
+ ad7280_write_channel_config,
+ AD7280A_CELL_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_high_value,
+ in-in_thresh_high_value,
+ S_IRUGO | S_IWUSR,
+ ad7280_read_channel_config,
+ ad7280_write_channel_config,
+ AD7280A_CELL_OVERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_low_value,
+ S_IRUGO | S_IWUSR,
+ ad7280_read_channel_config,
+ ad7280_write_channel_config,
+ AD7280A_AUX_ADC_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_high_value,
+ S_IRUGO | S_IWUSR,
+ ad7280_read_channel_config,
+ ad7280_write_channel_config,
+ AD7280A_AUX_ADC_OVERVOLTAGE);
+
+
+static struct attribute *ad7280_event_attributes[] = {
+ &iio_dev_attr_in_thresh_low_value.dev_attr.attr,
+ &iio_dev_attr_in_thresh_high_value.dev_attr.attr,
+ &iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
+ &iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
+ NULL,
+};
+
+static struct attribute_group ad7280_event_attrs_group = {
+ .attrs = ad7280_event_attributes,
+};
+
+static int ad7280_read_raw(struct iio_dev *dev_info,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ struct ad7280_state *st = iio_priv(dev_info);
+ unsigned int scale_uv;
+ int ret;
+
+ switch (m) {
+ case 0:
+ mutex_lock(&dev_info->mlock);
+ 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(&dev_info->mlock);
+
+ if (ret < 0)
+ return ret;
+
+ *val = ret;
+
+ return IIO_VAL_INT;
+ case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+ if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
+ scale_uv = (4000 * 1000) >> AD7280A_BITS;
+ else
+ scale_uv = (5000 * 1000) >> AD7280A_BITS;
+
+ *val = scale_uv / 1000;
+ *val2 = (scale_uv % 1000) * 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ return -EINVAL;
+}
+
+static const struct iio_info ad7280_info = {
+ .read_raw = &ad7280_read_raw,
+ .num_interrupt_lines = 1,
+ .event_attrs = &ad7280_event_attrs_group,
+ .attrs = &ad7280_attrs_group,
+ .driver_module = THIS_MODULE,
+};
+
+static const struct ad7280_platform_data ad7793_default_pdata = {
+ .acquisition_time = AD7280A_ACQ_TIME_400ns,
+ .conversion_averaging = AD7280A_CONV_AVG_DIS,
+ .thermistor_term_en = true,
+};
+
+static int __devinit ad7280_probe(struct spi_device *spi)
+{
+ const struct ad7280_platform_data *pdata = spi->dev.platform_data;
+ struct ad7280_state *st;
+ int ret, regdone = 0;
+ const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
+ const unsigned short nAVG[4] = {1, 2, 4, 8};
+ struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
+
+ if (indio_dev == NULL)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ spi_set_drvdata(spi, indio_dev);
+ st->spi = spi;
+
+ if (!pdata)
+ pdata = &ad7793_default_pdata;
+
+ ad7280_crc8_build_table(st->crc_tab);
+
+ st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
+ st->spi->mode = SPI_MODE_1;
+ spi_setup(st->spi);
+
+ st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
+ st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
+ & 0x3) | (pdata->thermistor_term_en ?
+ AD7280A_CTRL_LB_THERMISTOR_EN : 0);
+
+ ret = ad7280_chain_setup(st);
+ if (ret < 0)
+ goto error_free_device;
+
+ st->slave_num = ret;
+ st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
+ st->cell_threshhigh = 0xFF;
+ st->aux_threshhigh = 0xFF;
+
+ /*
+ * Total Conversion Time = ((tACQ + tCONV) *
+ * (Number of Conversions per Part)) −
+ * tACQ + ((N - 1) * tDELAY)
+ *
+ * Readback Delay = Total Conversion Time + tWAIT
+ */
+
+ st->readback_delay_us =
+ ((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
+ (AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
+ - tACQ_ns[pdata->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 */
+
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = ad7280_channel_init(st);
+ if (ret < 0)
+ goto error_free_device;
+
+ indio_dev->num_channels = ret;
+ indio_dev->channels = st->channels;
+ indio_dev->info = &ad7280_info;
+
+ ret = ad7280_attr_init(st);
+ if (ret < 0)
+ goto error_free_channels;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_free_attr;
+ regdone = 1;
+
+ if (spi->irq > 0) {
+ ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+ AD7280A_ALERT, 1,
+ AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
+ if (ret)
+ goto error_free_attr;
+
+ ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
+ AD7280A_ALERT, 0,
+ AD7280A_ALERT_GEN_STATIC_HIGH |
+ (pdata->chain_last_alert_ignore & 0xF));
+ if (ret)
+ goto error_free_attr;
+
+ ret = request_threaded_irq(spi->irq,
+ NULL,
+ ad7280_event_handler,
+ IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ indio_dev->name,
+ indio_dev);
+ if (ret)
+ goto error_free_attr;
+ }
+
+ return 0;
+
+error_free_attr:
+ kfree(st->iio_attr);
+
+error_free_channels:
+ kfree(st->channels);
+
+error_free_device:
+ if (regdone)
+ iio_device_unregister(indio_dev);
+ else
+ iio_free_device(indio_dev);
+
+ return ret;
+}
+
+static int __devexit ad7280_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad7280_state *st = iio_priv(indio_dev);
+
+ if (spi->irq > 0)
+ free_irq(spi->irq, indio_dev);
+
+ ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+ AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
+
+ kfree(st->channels);
+ kfree(st->iio_attr);
+ iio_device_unregister(indio_dev);
+
+ return 0;
+}
+
+static const struct spi_device_id ad7280_id[] = {
+ {"ad7280a", 0},
+ {}
+};
+
+static struct spi_driver ad7280_driver = {
+ .driver = {
+ .name = "ad7280",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+ .probe = ad7280_probe,
+ .remove = __devexit_p(ad7280_remove),
+ .id_table = ad7280_id,
+};
+
+static int __init ad7280_init(void)
+{
+ return spi_register_driver(&ad7280_driver);
+}
+module_init(ad7280_init);
+
+static void __exit ad7280_exit(void)
+{
+ spi_unregister_driver(&ad7280_driver);
+}
+module_exit(ad7280_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7280A");
+MODULE_LICENSE("GPL v2");