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1// SPDX-License-Identifier: GPL-2.02/*3 * AD7280A Lithium Ion Battery Monitoring System4 *5 * Copyright 2011 Analog Devices Inc.6 */7 8#include <linux/bitfield.h>9#include <linux/bits.h>10#include <linux/cleanup.h>11#include <linux/crc8.h>12#include <linux/delay.h>13#include <linux/device.h>14#include <linux/err.h>15#include <linux/interrupt.h>16#include <linux/kernel.h>17#include <linux/module.h>18#include <linux/mod_devicetable.h>19#include <linux/mutex.h>20#include <linux/slab.h>21#include <linux/sysfs.h>22#include <linux/spi/spi.h>23 24#include <linux/iio/events.h>25#include <linux/iio/iio.h>26 27/* Registers */28 29#define AD7280A_CELL_VOLTAGE_1_REG		0x0  /* D11 to D0, Read only */30#define AD7280A_CELL_VOLTAGE_2_REG		0x1  /* D11 to D0, Read only */31#define AD7280A_CELL_VOLTAGE_3_REG		0x2  /* D11 to D0, Read only */32#define AD7280A_CELL_VOLTAGE_4_REG		0x3  /* D11 to D0, Read only */33#define AD7280A_CELL_VOLTAGE_5_REG		0x4  /* D11 to D0, Read only */34#define AD7280A_CELL_VOLTAGE_6_REG		0x5  /* D11 to D0, Read only */35#define AD7280A_AUX_ADC_1_REG			0x6  /* D11 to D0, Read only */36#define AD7280A_AUX_ADC_2_REG			0x7  /* D11 to D0, Read only */37#define AD7280A_AUX_ADC_3_REG			0x8  /* D11 to D0, Read only */38#define AD7280A_AUX_ADC_4_REG			0x9  /* D11 to D0, Read only */39#define AD7280A_AUX_ADC_5_REG			0xA  /* D11 to D0, Read only */40#define AD7280A_AUX_ADC_6_REG			0xB  /* D11 to D0, Read only */41#define AD7280A_SELF_TEST_REG			0xC  /* D11 to D0, Read only */42 43#define AD7280A_CTRL_HB_REG			0xD  /* D15 to D8, Read/write */44#define   AD7280A_CTRL_HB_CONV_INPUT_MSK		GENMASK(7, 6)45#define     AD7280A_CTRL_HB_CONV_INPUT_ALL			046#define     AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_5		147#define     AD7280A_CTRL_HB_CONV_INPUT_6CELL			248#define     AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		349#define   AD7280A_CTRL_HB_CONV_RREAD_MSK		GENMASK(5, 4)50#define     AD7280A_CTRL_HB_CONV_RREAD_ALL			051#define     AD7280A_CTRL_HB_CONV_RREAD_6CELL_AUX1_3_5		152#define     AD7280A_CTRL_HB_CONV_RREAD_6CELL			253#define     AD7280A_CTRL_HB_CONV_RREAD_NO		        354#define   AD7280A_CTRL_HB_CONV_START_MSK		BIT(3)55#define     AD7280A_CTRL_HB_CONV_START_CNVST			056#define     AD7280A_CTRL_HB_CONV_START_CS			157#define   AD7280A_CTRL_HB_CONV_AVG_MSK			GENMASK(2, 1)58#define     AD7280A_CTRL_HB_CONV_AVG_DIS			059#define     AD7280A_CTRL_HB_CONV_AVG_2				160#define     AD7280A_CTRL_HB_CONV_AVG_4			        261#define     AD7280A_CTRL_HB_CONV_AVG_8			        362#define   AD7280A_CTRL_HB_PWRDN_SW			BIT(0)63 64#define AD7280A_CTRL_LB_REG			0xE  /* D7 to D0, Read/write */65#define   AD7280A_CTRL_LB_SWRST_MSK			BIT(7)66#define   AD7280A_CTRL_LB_ACQ_TIME_MSK			GENMASK(6, 5)67#define     AD7280A_CTRL_LB_ACQ_TIME_400ns			068#define     AD7280A_CTRL_LB_ACQ_TIME_800ns			169#define     AD7280A_CTRL_LB_ACQ_TIME_1200ns			270#define     AD7280A_CTRL_LB_ACQ_TIME_1600ns			371#define   AD7280A_CTRL_LB_MUST_SET			BIT(4)72#define   AD7280A_CTRL_LB_THERMISTOR_MSK		BIT(3)73#define   AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK		BIT(2)74#define   AD7280A_CTRL_LB_INC_DEV_ADDR_MSK		BIT(1)75#define   AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK		BIT(0)76 77#define AD7280A_CELL_OVERVOLTAGE_REG		0xF  /* D7 to D0, Read/write */78#define AD7280A_CELL_UNDERVOLTAGE_REG		0x10 /* D7 to D0, Read/write */79#define AD7280A_AUX_ADC_OVERVOLTAGE_REG		0x11 /* D7 to D0, Read/write */80#define AD7280A_AUX_ADC_UNDERVOLTAGE_REG	0x12 /* D7 to D0, Read/write */81 82#define AD7280A_ALERT_REG			0x13 /* D7 to D0, Read/write */83#define   AD7280A_ALERT_REMOVE_MSK			GENMASK(3, 0)84#define     AD7280A_ALERT_REMOVE_AUX5			BIT(0)85#define     AD7280A_ALERT_REMOVE_AUX3_AUX5		BIT(1)86#define     AD7280A_ALERT_REMOVE_VIN5			BIT(2)87#define     AD7280A_ALERT_REMOVE_VIN4_VIN5		BIT(3)88#define   AD7280A_ALERT_GEN_STATIC_HIGH			BIT(6)89#define   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(BIT(7) | BIT(6))90 91#define AD7280A_CELL_BALANCE_REG		0x14 /* D7 to D0, Read/write */92#define  AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK		GENMASK(7, 2)93#define AD7280A_CB1_TIMER_REG			0x15 /* D7 to D0, Read/write */94#define  AD7280A_CB_TIMER_VAL_MSK			GENMASK(7, 3)95#define AD7280A_CB2_TIMER_REG			0x16 /* D7 to D0, Read/write */96#define AD7280A_CB3_TIMER_REG			0x17 /* D7 to D0, Read/write */97#define AD7280A_CB4_TIMER_REG			0x18 /* D7 to D0, Read/write */98#define AD7280A_CB5_TIMER_REG			0x19 /* D7 to D0, Read/write */99#define AD7280A_CB6_TIMER_REG			0x1A /* D7 to D0, Read/write */100#define AD7280A_PD_TIMER_REG			0x1B /* D7 to D0, Read/write */101#define AD7280A_READ_REG			0x1C /* D7 to D0, Read/write */102#define   AD7280A_READ_ADDR_MSK				GENMASK(7, 2)103#define AD7280A_CNVST_CTRL_REG			0x1D /* D7 to D0, Read/write */104 105/* Transfer fields */106#define AD7280A_TRANS_WRITE_DEVADDR_MSK		GENMASK(31, 27)107#define AD7280A_TRANS_WRITE_ADDR_MSK		GENMASK(26, 21)108#define AD7280A_TRANS_WRITE_VAL_MSK		GENMASK(20, 13)109#define AD7280A_TRANS_WRITE_ALL_MSK		BIT(12)110#define AD7280A_TRANS_WRITE_CRC_MSK		GENMASK(10, 3)111#define AD7280A_TRANS_WRITE_RES_PATTERN		0x2112 113/* Layouts differ for channel vs other registers */114#define AD7280A_TRANS_READ_DEVADDR_MSK		GENMASK(31, 27)115#define AD7280A_TRANS_READ_CONV_CHANADDR_MSK	GENMASK(26, 23)116#define AD7280A_TRANS_READ_CONV_DATA_MSK	GENMASK(22, 11)117#define AD7280A_TRANS_READ_REG_REGADDR_MSK	GENMASK(26, 21)118#define AD7280A_TRANS_READ_REG_DATA_MSK		GENMASK(20, 13)119#define AD7280A_TRANS_READ_WRITE_ACK_MSK	BIT(10)120#define AD7280A_TRANS_READ_CRC_MSK		GENMASK(9, 2)121 122/* Magic value used to indicate this special case */123#define AD7280A_ALL_CELLS				(0xAD << 16)124 125#define AD7280A_MAX_SPI_CLK_HZ		700000 /* < 1MHz */126#define AD7280A_MAX_CHAIN		8127#define AD7280A_CELLS_PER_DEV		6128#define AD7280A_BITS			12129#define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6_REG - \130					AD7280A_CELL_VOLTAGE_1_REG + 1)131 132#define AD7280A_CALC_VOLTAGE_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \133					     (c))134#define AD7280A_CALC_TEMP_CHAN_NUM(d, c)    (((d) * AD7280A_CELLS_PER_DEV) + \135					     (c) - AD7280A_CELLS_PER_DEV)136 137#define AD7280A_DEVADDR_MASTER		0138#define AD7280A_DEVADDR_ALL		0x1F139 140static const unsigned short ad7280a_n_avg[4] = {1, 2, 4, 8};141static const unsigned short ad7280a_t_acq_ns[4] = {470, 1030, 1510, 1945};142 143/* 5-bit device address is sent LSB first */144static unsigned int ad7280a_devaddr(unsigned int addr)145{146	return ((addr & 0x1) << 4) |147	       ((addr & 0x2) << 2) |148	       (addr & 0x4) |149	       ((addr & 0x8) >> 2) |150	       ((addr & 0x10) >> 4);151}152 153/*154 * During a read a valid write is mandatory.155 * So writing to the highest available address (Address 0x1F) and setting the156 * address all parts bit to 0 is recommended.157 * So the TXVAL is AD7280A_DEVADDR_ALL + CRC158 */159#define AD7280A_READ_TXVAL	0xF800030A160 161/*162 * AD7280 CRC163 *164 * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F165 */166#define POLYNOM		0x2F167 168struct ad7280_state {169	struct spi_device		*spi;170	struct iio_chan_spec		*channels;171	unsigned int			chain_last_alert_ignore;172	bool				thermistor_term_en;173	int				slave_num;174	int				scan_cnt;175	int				readback_delay_us;176	unsigned char			crc_tab[CRC8_TABLE_SIZE];177	u8				oversampling_ratio;178	u8				acquisition_time;179	unsigned char			ctrl_lb;180	unsigned char			cell_threshhigh;181	unsigned char			cell_threshlow;182	unsigned char			aux_threshhigh;183	unsigned char			aux_threshlow;184	unsigned char			cb_mask[AD7280A_MAX_CHAIN];185	struct mutex			lock; /* protect sensor state */186 187	__be32				tx __aligned(IIO_DMA_MINALIGN);188	__be32				rx;189};190 191static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned int val)192{193	unsigned char crc;194 195	crc = crc_tab[val >> 16 & 0xFF];196	crc = crc_tab[crc ^ (val >> 8 & 0xFF)];197 198	return crc ^ (val & 0xFF);199}200 201static int ad7280_check_crc(struct ad7280_state *st, unsigned int val)202{203	unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);204 205	if (crc != ((val >> 2) & 0xFF))206		return -EIO;207 208	return 0;209}210 211/*212 * After initiating a conversion sequence we need to wait until the conversion213 * is done. The delay is typically in the range of 15..30us however depending on214 * the number of devices in the daisy chain, the number of averages taken,215 * conversion delays and acquisition time options it may take up to 250us, in216 * this case we better sleep instead of busy wait.217 */218 219static void ad7280_delay(struct ad7280_state *st)220{221	if (st->readback_delay_us < 50)222		udelay(st->readback_delay_us);223	else224		usleep_range(250, 500);225}226 227static int __ad7280_read32(struct ad7280_state *st, unsigned int *val)228{229	int ret;230	struct spi_transfer t = {231		.tx_buf	= &st->tx,232		.rx_buf = &st->rx,233		.len = sizeof(st->tx),234	};235 236	st->tx = cpu_to_be32(AD7280A_READ_TXVAL);237 238	ret = spi_sync_transfer(st->spi, &t, 1);239	if (ret)240		return ret;241 242	*val = be32_to_cpu(st->rx);243 244	return 0;245}246 247static int ad7280_write(struct ad7280_state *st, unsigned int devaddr,248			unsigned int addr, bool all, unsigned int val)249{250	unsigned int reg = FIELD_PREP(AD7280A_TRANS_WRITE_DEVADDR_MSK, devaddr) |251		FIELD_PREP(AD7280A_TRANS_WRITE_ADDR_MSK, addr) |252		FIELD_PREP(AD7280A_TRANS_WRITE_VAL_MSK, val) |253		FIELD_PREP(AD7280A_TRANS_WRITE_ALL_MSK, all);254 255	reg |= FIELD_PREP(AD7280A_TRANS_WRITE_CRC_MSK,256			ad7280_calc_crc8(st->crc_tab, reg >> 11));257	/* Reserved b010 pattern not included crc calc */258	reg |= AD7280A_TRANS_WRITE_RES_PATTERN;259 260	st->tx = cpu_to_be32(reg);261 262	return spi_write(st->spi, &st->tx, sizeof(st->tx));263}264 265static int ad7280_read_reg(struct ad7280_state *st, unsigned int devaddr,266			   unsigned int addr)267{268	int ret;269	unsigned int tmp;270 271	/* turns off the read operation on all parts */272	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,273			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,274				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |275			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,276				      AD7280A_CTRL_HB_CONV_RREAD_NO) |277			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,278				      st->oversampling_ratio));279	if (ret)280		return ret;281 282	/* turns on the read operation on the addressed part */283	ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,284			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,285				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |286			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,287				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |288			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,289				      st->oversampling_ratio));290	if (ret)291		return ret;292 293	/* Set register address on the part to be read from */294	ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,295			   FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));296	if (ret)297		return ret;298 299	ret = __ad7280_read32(st, &tmp);300	if (ret)301		return ret;302 303	if (ad7280_check_crc(st, tmp))304		return -EIO;305 306	if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||307	    (FIELD_GET(AD7280A_TRANS_READ_REG_REGADDR_MSK, tmp) != addr))308		return -EFAULT;309 310	return FIELD_GET(AD7280A_TRANS_READ_REG_DATA_MSK, tmp);311}312 313static int ad7280_read_channel(struct ad7280_state *st, unsigned int devaddr,314			       unsigned int addr)315{316	int ret;317	unsigned int tmp;318 319	ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,320			   FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));321	if (ret)322		return ret;323 324	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,325			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,326				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |327			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,328				      AD7280A_CTRL_HB_CONV_RREAD_NO) |329			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,330				      st->oversampling_ratio));331	if (ret)332		return ret;333 334	ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,335			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,336				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |337			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,338				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |339			   FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,340				      AD7280A_CTRL_HB_CONV_START_CS) |341			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,342				      st->oversampling_ratio));343	if (ret)344		return ret;345 346	ad7280_delay(st);347 348	ret = __ad7280_read32(st, &tmp);349	if (ret)350		return ret;351 352	if (ad7280_check_crc(st, tmp))353		return -EIO;354 355	if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||356	    (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) != addr))357		return -EFAULT;358 359	return FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);360}361 362static int ad7280_read_all_channels(struct ad7280_state *st, unsigned int cnt,363				    unsigned int *array)364{365	int i, ret;366	unsigned int tmp, sum = 0;367 368	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,369			   AD7280A_CELL_VOLTAGE_1_REG << 2);370	if (ret)371		return ret;372 373	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,374			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,375				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |376			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,377				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |378			   FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,379				      AD7280A_CTRL_HB_CONV_START_CS) |380			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,381				      st->oversampling_ratio));382	if (ret)383		return ret;384 385	ad7280_delay(st);386 387	for (i = 0; i < cnt; i++) {388		ret = __ad7280_read32(st, &tmp);389		if (ret)390			return ret;391 392		if (ad7280_check_crc(st, tmp))393			return -EIO;394 395		if (array)396			array[i] = tmp;397		/* only sum cell voltages */398		if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) <=399		    AD7280A_CELL_VOLTAGE_6_REG)400			sum += FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);401	}402 403	return sum;404}405 406static void ad7280_sw_power_down(void *data)407{408	struct ad7280_state *st = data;409 410	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,411		     AD7280A_CTRL_HB_PWRDN_SW |412		     FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));413}414 415static int ad7280_chain_setup(struct ad7280_state *st)416{417	unsigned int val, n;418	int ret;419 420	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,421			   FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |422			   FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |423			   AD7280A_CTRL_LB_MUST_SET |424			   FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 1) |425			   st->ctrl_lb);426	if (ret)427		return ret;428 429	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,430			   FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |431			   FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |432			   AD7280A_CTRL_LB_MUST_SET |433			   FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 0) |434			   st->ctrl_lb);435	if (ret)436		goto error_power_down;437 438	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,439			   FIELD_PREP(AD7280A_READ_ADDR_MSK, AD7280A_CTRL_LB_REG));440	if (ret)441		goto error_power_down;442 443	for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {444		ret = __ad7280_read32(st, &val);445		if (ret)446			goto error_power_down;447 448		if (val == 0)449			return n - 1;450 451		if (ad7280_check_crc(st, val)) {452			ret = -EIO;453			goto error_power_down;454		}455 456		if (n != ad7280a_devaddr(FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, val))) {457			ret = -EIO;458			goto error_power_down;459		}460	}461	ret = -EFAULT;462 463error_power_down:464	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,465		     AD7280A_CTRL_HB_PWRDN_SW |466		     FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));467 468	return ret;469}470 471static ssize_t ad7280_show_balance_sw(struct iio_dev *indio_dev,472				      uintptr_t private,473				      const struct iio_chan_spec *chan, char *buf)474{475	struct ad7280_state *st = iio_priv(indio_dev);476 477	return sysfs_emit(buf, "%d\n",478			  !!(st->cb_mask[chan->address >> 8] &479			     BIT(chan->address & 0xFF)));480}481 482static ssize_t ad7280_store_balance_sw(struct iio_dev *indio_dev,483				       uintptr_t private,484				       const struct iio_chan_spec *chan,485				       const char *buf, size_t len)486{487	struct ad7280_state *st = iio_priv(indio_dev);488	unsigned int devaddr, ch;489	bool readin;490	int ret;491 492	ret = kstrtobool(buf, &readin);493	if (ret)494		return ret;495 496	devaddr = chan->address >> 8;497	ch = chan->address & 0xFF;498 499	mutex_lock(&st->lock);500	if (readin)501		st->cb_mask[devaddr] |= BIT(ch);502	else503		st->cb_mask[devaddr] &= ~BIT(ch);504 505	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE_REG, 0,506			   FIELD_PREP(AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK,507				      st->cb_mask[devaddr]));508	mutex_unlock(&st->lock);509 510	return ret ? ret : len;511}512 513static ssize_t ad7280_show_balance_timer(struct iio_dev *indio_dev,514					 uintptr_t private,515					 const struct iio_chan_spec *chan,516					 char *buf)517{518	struct ad7280_state *st = iio_priv(indio_dev);519	unsigned int msecs;520	int ret;521 522	mutex_lock(&st->lock);523	ret = ad7280_read_reg(st, chan->address >> 8,524			      (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG);525	mutex_unlock(&st->lock);526 527	if (ret < 0)528		return ret;529 530	msecs = FIELD_GET(AD7280A_CB_TIMER_VAL_MSK, ret) * 71500;531 532	return sysfs_emit(buf, "%u.%u\n", msecs / 1000, msecs % 1000);533}534 535static ssize_t ad7280_store_balance_timer(struct iio_dev *indio_dev,536					  uintptr_t private,537					  const struct iio_chan_spec *chan,538					  const char *buf, size_t len)539{540	struct ad7280_state *st = iio_priv(indio_dev);541	int val, val2;542	int ret;543 544	ret = iio_str_to_fixpoint(buf, 1000, &val, &val2);545	if (ret)546		return ret;547 548	val = val * 1000 + val2;549	val /= 71500;550 551	if (val > 31)552		return -EINVAL;553 554	mutex_lock(&st->lock);555	ret = ad7280_write(st, chan->address >> 8,556			   (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG, 0,557			   FIELD_PREP(AD7280A_CB_TIMER_VAL_MSK, val));558	mutex_unlock(&st->lock);559 560	return ret ? ret : len;561}562 563static const struct iio_chan_spec_ext_info ad7280_cell_ext_info[] = {564	{565		.name = "balance_switch_en",566		.read = ad7280_show_balance_sw,567		.write = ad7280_store_balance_sw,568		.shared = IIO_SEPARATE,569	}, {570		.name = "balance_switch_timer",571		.read = ad7280_show_balance_timer,572		.write = ad7280_store_balance_timer,573		.shared = IIO_SEPARATE,574	},575	{}576};577 578static const struct iio_event_spec ad7280_events[] = {579	{580		.type = IIO_EV_TYPE_THRESH,581		.dir = IIO_EV_DIR_RISING,582		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),583	}, {584		.type = IIO_EV_TYPE_THRESH,585		.dir = IIO_EV_DIR_FALLING,586		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),587	},588};589 590static void ad7280_voltage_channel_init(struct iio_chan_spec *chan, int i,591					bool irq_present)592{593	chan->type = IIO_VOLTAGE;594	chan->differential = 1;595	chan->channel = i;596	chan->channel2 = chan->channel + 1;597	if (irq_present) {598		chan->event_spec = ad7280_events;599		chan->num_event_specs = ARRAY_SIZE(ad7280_events);600	}601	chan->ext_info = ad7280_cell_ext_info;602}603 604static void ad7280_temp_channel_init(struct iio_chan_spec *chan, int i,605				     bool irq_present)606{607	chan->type = IIO_TEMP;608	chan->channel = i;609	if (irq_present) {610		chan->event_spec = ad7280_events;611		chan->num_event_specs = ARRAY_SIZE(ad7280_events);612	}613}614 615static void ad7280_common_fields_init(struct iio_chan_spec *chan, int addr,616				      int cnt)617{618	chan->indexed = 1;619	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);620	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);621	chan->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);622	chan->address = addr;623	chan->scan_index = cnt;624	chan->scan_type.sign = 'u';625	chan->scan_type.realbits = 12;626	chan->scan_type.storagebits = 32;627}628 629static void ad7280_total_voltage_channel_init(struct iio_chan_spec *chan,630					      int cnt, int dev)631{632	chan->type = IIO_VOLTAGE;633	chan->differential = 1;634	chan->channel = 0;635	chan->channel2 = dev * AD7280A_CELLS_PER_DEV;636	chan->address = AD7280A_ALL_CELLS;637	chan->indexed = 1;638	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);639	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);640	chan->scan_index = cnt;641	chan->scan_type.sign = 'u';642	chan->scan_type.realbits = 32;643	chan->scan_type.storagebits = 32;644}645 646static void ad7280_init_dev_channels(struct ad7280_state *st, int dev, int *cnt,647				     bool irq_present)648{649	int addr, ch, i;650	struct iio_chan_spec *chan;651 652	for (ch = AD7280A_CELL_VOLTAGE_1_REG; ch <= AD7280A_AUX_ADC_6_REG; ch++) {653		chan = &st->channels[*cnt];654 655		if (ch < AD7280A_AUX_ADC_1_REG) {656			i = AD7280A_CALC_VOLTAGE_CHAN_NUM(dev, ch);657			ad7280_voltage_channel_init(chan, i, irq_present);658		} else {659			i = AD7280A_CALC_TEMP_CHAN_NUM(dev, ch);660			ad7280_temp_channel_init(chan, i, irq_present);661		}662 663		addr = ad7280a_devaddr(dev) << 8 | ch;664		ad7280_common_fields_init(chan, addr, *cnt);665 666		(*cnt)++;667	}668}669 670static int ad7280_channel_init(struct ad7280_state *st, bool irq_present)671{672	int dev, cnt = 0;673 674	st->channels = devm_kcalloc(&st->spi->dev, (st->slave_num + 1) * 12 + 1,675				    sizeof(*st->channels), GFP_KERNEL);676	if (!st->channels)677		return -ENOMEM;678 679	for (dev = 0; dev <= st->slave_num; dev++)680		ad7280_init_dev_channels(st, dev, &cnt, irq_present);681 682	ad7280_total_voltage_channel_init(&st->channels[cnt], cnt, dev);683 684	return cnt + 1;685}686 687static int ad7280a_read_thresh(struct iio_dev *indio_dev,688			       const struct iio_chan_spec *chan,689			       enum iio_event_type type,690			       enum iio_event_direction dir,691			       enum iio_event_info info, int *val, int *val2)692{693	struct ad7280_state *st = iio_priv(indio_dev);694 695	switch (chan->type) {696	case IIO_VOLTAGE:697		switch (dir) {698		case IIO_EV_DIR_RISING:699			*val = 1000 + (st->cell_threshhigh * 1568L) / 100;700			return IIO_VAL_INT;701		case IIO_EV_DIR_FALLING:702			*val = 1000 + (st->cell_threshlow * 1568L) / 100;703			return IIO_VAL_INT;704		default:705			return -EINVAL;706		}707		break;708	case IIO_TEMP:709		switch (dir) {710		case IIO_EV_DIR_RISING:711			*val = ((st->aux_threshhigh) * 196L) / 10;712			return IIO_VAL_INT;713		case IIO_EV_DIR_FALLING:714			*val = (st->aux_threshlow * 196L) / 10;715			return IIO_VAL_INT;716		default:717			return -EINVAL;718		}719		break;720	default:721		return -EINVAL;722	}723}724 725static int ad7280a_write_thresh(struct iio_dev *indio_dev,726				const struct iio_chan_spec *chan,727				enum iio_event_type type,728				enum iio_event_direction dir,729				enum iio_event_info info,730				int val, int val2)731{732	struct ad7280_state *st = iio_priv(indio_dev);733	unsigned int addr;734	long value;735	int ret;736 737	if (val2 != 0)738		return -EINVAL;739 740	mutex_lock(&st->lock);741	switch (chan->type) {742	case IIO_VOLTAGE:743		value = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */744		value = clamp(value, 0L, 0xFFL);745		switch (dir) {746		case IIO_EV_DIR_RISING:747			addr = AD7280A_CELL_OVERVOLTAGE_REG;748			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,749					   1, value);750			if (ret)751				break;752			st->cell_threshhigh = value;753			break;754		case IIO_EV_DIR_FALLING:755			addr = AD7280A_CELL_UNDERVOLTAGE_REG;756			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,757					   1, value);758			if (ret)759				break;760			st->cell_threshlow = value;761			break;762		default:763			ret = -EINVAL;764			goto err_unlock;765		}766		break;767	case IIO_TEMP:768		value = (val * 10) / 196; /* LSB 19.6mV */769		value = clamp(value, 0L, 0xFFL);770		switch (dir) {771		case IIO_EV_DIR_RISING:772			addr = AD7280A_AUX_ADC_OVERVOLTAGE_REG;773			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,774					   1, value);775			if (ret)776				break;777			st->aux_threshhigh = value;778			break;779		case IIO_EV_DIR_FALLING:780			addr = AD7280A_AUX_ADC_UNDERVOLTAGE_REG;781			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,782					   1, value);783			if (ret)784				break;785			st->aux_threshlow = value;786			break;787		default:788			ret = -EINVAL;789			goto err_unlock;790		}791		break;792	default:793		ret = -EINVAL;794		goto err_unlock;795	}796 797err_unlock:798	mutex_unlock(&st->lock);799 800	return ret;801}802 803static irqreturn_t ad7280_event_handler(int irq, void *private)804{805	struct iio_dev *indio_dev = private;806	struct ad7280_state *st = iio_priv(indio_dev);807	int i, ret;808 809	unsigned int *channels __free(kfree) = kcalloc(st->scan_cnt, sizeof(*channels),810						       GFP_KERNEL);811	if (!channels)812		return IRQ_HANDLED;813 814	ret = ad7280_read_all_channels(st, st->scan_cnt, channels);815	if (ret < 0)816		return IRQ_HANDLED;817 818	for (i = 0; i < st->scan_cnt; i++) {819		unsigned int val;820 821		val = FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, channels[i]);822		if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, channels[i]) <=823		    AD7280A_CELL_VOLTAGE_6_REG) {824			if (val >= st->cell_threshhigh) {825				u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,826							 IIO_EV_DIR_RISING,827							 IIO_EV_TYPE_THRESH,828							 0, 0, 0);829				iio_push_event(indio_dev, tmp,830					       iio_get_time_ns(indio_dev));831			} else if (val <= st->cell_threshlow) {832				u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,833							 IIO_EV_DIR_FALLING,834							 IIO_EV_TYPE_THRESH,835							 0, 0, 0);836				iio_push_event(indio_dev, tmp,837					       iio_get_time_ns(indio_dev));838			}839		} else {840			if (val >= st->aux_threshhigh) {841				u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,842							IIO_EV_TYPE_THRESH,843							IIO_EV_DIR_RISING);844				iio_push_event(indio_dev, tmp,845					       iio_get_time_ns(indio_dev));846			} else if (val <= st->aux_threshlow) {847				u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,848							IIO_EV_TYPE_THRESH,849							IIO_EV_DIR_FALLING);850				iio_push_event(indio_dev, tmp,851					       iio_get_time_ns(indio_dev));852			}853		}854	}855 856	return IRQ_HANDLED;857}858 859static void ad7280_update_delay(struct ad7280_state *st)860{861	/*862	 * Total Conversion Time = ((tACQ + tCONV) *863	 *			   (Number of Conversions per Part)) −864	 *			   tACQ + ((N - 1) * tDELAY)865	 *866	 * Readback Delay = Total Conversion Time + tWAIT867	 */868 869	st->readback_delay_us =870		((ad7280a_t_acq_ns[st->acquisition_time & 0x3] + 720) *871			(AD7280A_NUM_CH * ad7280a_n_avg[st->oversampling_ratio & 0x3])) -872		ad7280a_t_acq_ns[st->acquisition_time & 0x3] + st->slave_num * 250;873 874	/* Convert to usecs */875	st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);876	st->readback_delay_us += 5; /* Add tWAIT */877}878 879static int ad7280_read_raw(struct iio_dev *indio_dev,880			   struct iio_chan_spec const *chan,881			   int *val,882			   int *val2,883			   long m)884{885	struct ad7280_state *st = iio_priv(indio_dev);886	int ret;887 888	switch (m) {889	case IIO_CHAN_INFO_RAW:890		mutex_lock(&st->lock);891		if (chan->address == AD7280A_ALL_CELLS)892			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);893		else894			ret = ad7280_read_channel(st, chan->address >> 8,895						  chan->address & 0xFF);896		mutex_unlock(&st->lock);897 898		if (ret < 0)899			return ret;900 901		*val = ret;902 903		return IIO_VAL_INT;904	case IIO_CHAN_INFO_SCALE:905		if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6_REG)906			*val = 4000;907		else908			*val = 5000;909 910		*val2 = AD7280A_BITS;911		return IIO_VAL_FRACTIONAL_LOG2;912	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:913		*val = ad7280a_n_avg[st->oversampling_ratio];914		return IIO_VAL_INT;915	}916	return -EINVAL;917}918 919static int ad7280_write_raw(struct iio_dev *indio_dev,920			    struct iio_chan_spec const *chan,921			    int val, int val2, long mask)922{923	struct ad7280_state *st = iio_priv(indio_dev);924	int i;925 926	switch (mask) {927	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:928		if (val2 != 0)929			return -EINVAL;930		for (i = 0; i < ARRAY_SIZE(ad7280a_n_avg); i++) {931			if (val == ad7280a_n_avg[i]) {932				st->oversampling_ratio = i;933				ad7280_update_delay(st);934				return 0;935			}936		}937		return -EINVAL;938	default:939		return -EINVAL;940	}941}942 943static const struct iio_info ad7280_info = {944	.read_raw = ad7280_read_raw,945	.write_raw = ad7280_write_raw,946	.read_event_value = &ad7280a_read_thresh,947	.write_event_value = &ad7280a_write_thresh,948};949 950static const struct iio_info ad7280_info_no_irq = {951	.read_raw = ad7280_read_raw,952	.write_raw = ad7280_write_raw,953};954 955static int ad7280_probe(struct spi_device *spi)956{957	struct device *dev = &spi->dev;958	struct ad7280_state *st;959	int ret;960	struct iio_dev *indio_dev;961 962	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));963	if (!indio_dev)964		return -ENOMEM;965 966	st = iio_priv(indio_dev);967	spi_set_drvdata(spi, indio_dev);968	st->spi = spi;969	mutex_init(&st->lock);970 971	st->thermistor_term_en =972		device_property_read_bool(dev, "adi,thermistor-termination");973 974	if (device_property_present(dev, "adi,acquisition-time-ns")) {975		u32 val;976 977		ret = device_property_read_u32(dev, "adi,acquisition-time-ns", &val);978		if (ret)979			return ret;980 981		switch (val) {982		case 400:983			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;984			break;985		case 800:986			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_800ns;987			break;988		case 1200:989			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1200ns;990			break;991		case 1600:992			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1600ns;993			break;994		default:995			dev_err(dev, "Firmware provided acquisition time is invalid\n");996			return -EINVAL;997		}998	} else {999		st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;1000	}1001 1002	/* Alert masks are intended for when particular inputs are not wired up */1003	if (device_property_present(dev, "adi,voltage-alert-last-chan")) {1004		u32 val;1005 1006		ret = device_property_read_u32(dev, "adi,voltage-alert-last-chan", &val);1007		if (ret)1008			return ret;1009 1010		switch (val) {1011		case 3:1012			st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN4_VIN5;1013			break;1014		case 4:1015			st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN5;1016			break;1017		case 5:1018			break;1019		default:1020			dev_err(dev,1021				"Firmware provided last voltage alert channel invalid\n");1022			break;1023		}1024	}1025	crc8_populate_msb(st->crc_tab, POLYNOM);1026 1027	st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_HZ;1028	st->spi->mode = SPI_MODE_1;1029	spi_setup(st->spi);1030 1031	st->ctrl_lb = FIELD_PREP(AD7280A_CTRL_LB_ACQ_TIME_MSK, st->acquisition_time) |1032		FIELD_PREP(AD7280A_CTRL_LB_THERMISTOR_MSK, st->thermistor_term_en);1033	st->oversampling_ratio = 0; /* No oversampling */1034 1035	ret = ad7280_chain_setup(st);1036	if (ret < 0)1037		return ret;1038 1039	st->slave_num = ret;1040	st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;1041	st->cell_threshhigh = 0xFF;1042	st->aux_threshhigh = 0xFF;1043 1044	ret = devm_add_action_or_reset(dev, ad7280_sw_power_down, st);1045	if (ret)1046		return ret;1047 1048	ad7280_update_delay(st);1049 1050	indio_dev->name = spi_get_device_id(spi)->name;1051	indio_dev->modes = INDIO_DIRECT_MODE;1052 1053	ret = ad7280_channel_init(st, spi->irq > 0);1054	if (ret < 0)1055		return ret;1056 1057	indio_dev->num_channels = ret;1058	indio_dev->channels = st->channels;1059	if (spi->irq > 0) {1060		ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,1061				   AD7280A_ALERT_REG, 1,1062				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);1063		if (ret)1064			return ret;1065 1066		ret = ad7280_write(st, ad7280a_devaddr(st->slave_num),1067				   AD7280A_ALERT_REG, 0,1068				   AD7280A_ALERT_GEN_STATIC_HIGH |1069				   FIELD_PREP(AD7280A_ALERT_REMOVE_MSK,1070					      st->chain_last_alert_ignore));1071		if (ret)1072			return ret;1073 1074		ret = devm_request_threaded_irq(dev, spi->irq,1075						NULL,1076						ad7280_event_handler,1077						IRQF_TRIGGER_FALLING |1078						IRQF_ONESHOT,1079						indio_dev->name,1080						indio_dev);1081		if (ret)1082			return ret;1083 1084		indio_dev->info = &ad7280_info;1085	} else {1086		indio_dev->info = &ad7280_info_no_irq;1087	}1088 1089	return devm_iio_device_register(dev, indio_dev);1090}1091 1092static const struct spi_device_id ad7280_id[] = {1093	{ "ad7280a", 0 },1094	{ }1095};1096MODULE_DEVICE_TABLE(spi, ad7280_id);1097 1098static struct spi_driver ad7280_driver = {1099	.driver = {1100		.name	= "ad7280",1101	},1102	.probe		= ad7280_probe,1103	.id_table	= ad7280_id,1104};1105module_spi_driver(ad7280_driver);1106 1107MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");1108MODULE_DESCRIPTION("Analog Devices AD7280A");1109MODULE_LICENSE("GPL v2");1110