text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   * Hardware monitoring driver for LM25056 / LM25066 / LM5064 / LM5066
   *
   * Copyright (c) 2011 Ericsson AB.
   * Copyright (c) 2013 Guenter Roeck
   */
  
  #include <linux/bitops.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/i2c.h>
  #include <linux/log2.h>
  #include "pmbus.h"
  
  enum chips { lm25056, lm25066, lm5064, lm5066, lm5066i };
  
  #define LM25066_READ_VAUX		0xd0
  #define LM25066_MFR_READ_IIN		0xd1
  #define LM25066_MFR_READ_PIN		0xd2
  #define LM25066_MFR_IIN_OC_WARN_LIMIT	0xd3
  #define LM25066_MFR_PIN_OP_WARN_LIMIT	0xd4
  #define LM25066_READ_PIN_PEAK		0xd5
  #define LM25066_CLEAR_PIN_PEAK		0xd6
  #define LM25066_DEVICE_SETUP		0xd9
  #define LM25066_READ_AVG_VIN		0xdc
  #define LM25066_SAMPLES_FOR_AVG		0xdb
  #define LM25066_READ_AVG_VOUT		0xdd
  #define LM25066_READ_AVG_IIN		0xde
  #define LM25066_READ_AVG_PIN		0xdf
  
  #define LM25066_DEV_SETUP_CL		BIT(4)	/* Current limit */
  
  #define LM25066_SAMPLES_FOR_AVG_MAX	4096
  
  /* LM25056 only */
  
  #define LM25056_VAUX_OV_WARN_LIMIT	0xe3
  #define LM25056_VAUX_UV_WARN_LIMIT	0xe4
  
  #define LM25056_MFR_STS_VAUX_OV_WARN	BIT(1)
  #define LM25056_MFR_STS_VAUX_UV_WARN	BIT(0)
  
  struct __coeff {
  	short m, b, R;
  };
  
  #define PSC_CURRENT_IN_L	(PSC_NUM_CLASSES)
  #define PSC_POWER_L		(PSC_NUM_CLASSES + 1)
  
  static struct __coeff lm25066_coeff[][PSC_NUM_CLASSES + 2] = {
  	[lm25056] = {
  		[PSC_VOLTAGE_IN] = {
  			.m = 16296,
  			.b = 1343,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN] = {
  			.m = 13797,
  			.b = -1833,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN_L] = {
  			.m = 6726,
  			.b = -537,
  			.R = -2,
  		},
  		[PSC_POWER] = {
  			.m = 5501,
  			.b = -2908,
  			.R = -3,
  		},
  		[PSC_POWER_L] = {
  			.m = 26882,
  			.b = -5646,
  			.R = -4,
  		},
  		[PSC_TEMPERATURE] = {
  			.m = 1580,
  			.b = -14500,
  			.R = -2,
  		},
  	},
  	[lm25066] = {
  		[PSC_VOLTAGE_IN] = {
  			.m = 22070,
  			.b = -1800,
  			.R = -2,
  		},
  		[PSC_VOLTAGE_OUT] = {
  			.m = 22070,
  			.b = -1800,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN] = {
  			.m = 13661,
  			.b = -5200,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN_L] = {
  			.m = 6852,
  			.b = -3100,
  			.R = -2,
  		},
  		[PSC_POWER] = {
  			.m = 736,
  			.b = -3300,
  			.R = -2,
  		},
  		[PSC_POWER_L] = {
  			.m = 369,
  			.b = -1900,
  			.R = -2,
  		},
  		[PSC_TEMPERATURE] = {
  			.m = 16,
  		},
  	},
  	[lm5064] = {
  		[PSC_VOLTAGE_IN] = {
  			.m = 4611,
  			.b = -642,
  			.R = -2,
  		},
  		[PSC_VOLTAGE_OUT] = {
  			.m = 4621,
  			.b = 423,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN] = {
  			.m = 10742,
  			.b = 1552,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN_L] = {
  			.m = 5456,
  			.b = 2118,
  			.R = -2,
  		},
  		[PSC_POWER] = {
  			.m = 1204,
  			.b = 8524,
  			.R = -3,
  		},
  		[PSC_POWER_L] = {
  			.m = 612,
  			.b = 11202,
  			.R = -3,
  		},
  		[PSC_TEMPERATURE] = {
  			.m = 16,
  		},
  	},
  	[lm5066] = {
  		[PSC_VOLTAGE_IN] = {
  			.m = 4587,
  			.b = -1200,
  			.R = -2,
  		},
  		[PSC_VOLTAGE_OUT] = {
  			.m = 4587,
  			.b = -2400,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN] = {
  			.m = 10753,
  			.b = -1200,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN_L] = {
  			.m = 5405,
  			.b = -600,
  			.R = -2,
  		},
  		[PSC_POWER] = {
  			.m = 1204,
  			.b = -6000,
  			.R = -3,
  		},
  		[PSC_POWER_L] = {
  			.m = 605,
  			.b = -8000,
  			.R = -3,
  		},
  		[PSC_TEMPERATURE] = {
  			.m = 16,
  		},
  	},
  	[lm5066i] = {
  		[PSC_VOLTAGE_IN] = {
  			.m = 4617,
  			.b = -140,
  			.R = -2,
  		},
  		[PSC_VOLTAGE_OUT] = {
  			.m = 4602,
  			.b = 500,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN] = {
  			.m = 15076,
  			.b = -504,
  			.R = -2,
  		},
  		[PSC_CURRENT_IN_L] = {
  			.m = 7645,
  			.b = 100,
  			.R = -2,
  		},
  		[PSC_POWER] = {
  			.m = 1701,
  			.b = -4000,
  			.R = -3,
  		},
  		[PSC_POWER_L] = {
  			.m = 861,
  			.b = -965,
  			.R = -3,
  		},
  		[PSC_TEMPERATURE] = {
  			.m = 16,
  		},
  	},
  };
  
  struct lm25066_data {
  	int id;
  	u16 rlimit;			/* Maximum register value */
  	struct pmbus_driver_info info;
  };
  
  #define to_lm25066_data(x)  container_of(x, struct lm25066_data, info)
  
  static const struct i2c_device_id lm25066_id[];
  
  static int lm25066_read_word_data(struct i2c_client *client, int page,
  				  int phase, int reg)
  {
  	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
  	const struct lm25066_data *data = to_lm25066_data(info);
  	int ret;
  
  	switch (reg) {
  	case PMBUS_VIRT_READ_VMON:
  		ret = pmbus_read_word_data(client, 0, 0xff, LM25066_READ_VAUX);
  		if (ret < 0)
  			break;
  		/* Adjust returned value to match VIN coefficients */
  		switch (data->id) {
  		case lm25056:
  			/* VIN: 6.14 mV VAUX: 293 uV LSB */
  			ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
  			break;
  		case lm25066:
  			/* VIN: 4.54 mV VAUX: 283.2 uV LSB */
  			ret = DIV_ROUND_CLOSEST(ret * 2832, 45400);
  			break;
  		case lm5064:
  			/* VIN: 4.53 mV VAUX: 700 uV LSB */
  			ret = DIV_ROUND_CLOSEST(ret * 70, 453);
  			break;
  		case lm5066:
  		case lm5066i:
  			/* VIN: 2.18 mV VAUX: 725 uV LSB */
  			ret = DIV_ROUND_CLOSEST(ret * 725, 2180);
  			break;
  		}
  		break;
  	case PMBUS_READ_IIN:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_MFR_READ_IIN);
  		break;
  	case PMBUS_READ_PIN:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_MFR_READ_PIN);
  		break;
  	case PMBUS_IIN_OC_WARN_LIMIT:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_MFR_IIN_OC_WARN_LIMIT);
  		break;
  	case PMBUS_PIN_OP_WARN_LIMIT:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_MFR_PIN_OP_WARN_LIMIT);
  		break;
  	case PMBUS_VIRT_READ_VIN_AVG:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_READ_AVG_VIN);
  		break;
  	case PMBUS_VIRT_READ_VOUT_AVG:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_READ_AVG_VOUT);
  		break;
  	case PMBUS_VIRT_READ_IIN_AVG:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_READ_AVG_IIN);
  		break;
  	case PMBUS_VIRT_READ_PIN_AVG:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_READ_AVG_PIN);
  		break;
  	case PMBUS_VIRT_READ_PIN_MAX:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25066_READ_PIN_PEAK);
  		break;
  	case PMBUS_VIRT_RESET_PIN_HISTORY:
  		ret = 0;
  		break;
  	case PMBUS_VIRT_SAMPLES:
  		ret = pmbus_read_byte_data(client, 0, LM25066_SAMPLES_FOR_AVG);
  		if (ret < 0)
  			break;
  		ret = 1 << ret;
  		break;
  	default:
  		ret = -ENODATA;
  		break;
  	}
  	return ret;
  }
  
  static int lm25056_read_word_data(struct i2c_client *client, int page,
  				  int phase, int reg)
  {
  	int ret;
  
  	switch (reg) {
  	case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25056_VAUX_UV_WARN_LIMIT);
  		if (ret < 0)
  			break;
  		/* Adjust returned value to match VIN coefficients */
  		ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
  		break;
  	case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
  		ret = pmbus_read_word_data(client, 0, 0xff,
  					   LM25056_VAUX_OV_WARN_LIMIT);
  		if (ret < 0)
  			break;
  		/* Adjust returned value to match VIN coefficients */
  		ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
  		break;
  	default:
  		ret = lm25066_read_word_data(client, page, phase, reg);
  		break;
  	}
  	return ret;
  }
  
  static int lm25056_read_byte_data(struct i2c_client *client, int page, int reg)
  {
  	int ret, s;
  
  	switch (reg) {
  	case PMBUS_VIRT_STATUS_VMON:
  		ret = pmbus_read_byte_data(client, 0,
  					   PMBUS_STATUS_MFR_SPECIFIC);
  		if (ret < 0)
  			break;
  		s = 0;
  		if (ret & LM25056_MFR_STS_VAUX_UV_WARN)
  			s |= PB_VOLTAGE_UV_WARNING;
  		if (ret & LM25056_MFR_STS_VAUX_OV_WARN)
  			s |= PB_VOLTAGE_OV_WARNING;
  		ret = s;
  		break;
  	default:
  		ret = -ENODATA;
  		break;
  	}
  	return ret;
  }
  
  static int lm25066_write_word_data(struct i2c_client *client, int page, int reg,
  				   u16 word)
  {
  	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
  	const struct lm25066_data *data = to_lm25066_data(info);
  	int ret;
  
  	switch (reg) {
  	case PMBUS_POUT_OP_FAULT_LIMIT:
  	case PMBUS_POUT_OP_WARN_LIMIT:
  	case PMBUS_VOUT_UV_WARN_LIMIT:
  	case PMBUS_OT_FAULT_LIMIT:
  	case PMBUS_OT_WARN_LIMIT:
  	case PMBUS_IIN_OC_FAULT_LIMIT:
  	case PMBUS_VIN_UV_WARN_LIMIT:
  	case PMBUS_VIN_UV_FAULT_LIMIT:
  	case PMBUS_VIN_OV_FAULT_LIMIT:
  	case PMBUS_VIN_OV_WARN_LIMIT:
  		word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
  		ret = pmbus_write_word_data(client, 0, reg, word);
  		break;
  	case PMBUS_IIN_OC_WARN_LIMIT:
  		word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
  		ret = pmbus_write_word_data(client, 0,
  					    LM25066_MFR_IIN_OC_WARN_LIMIT,
  					    word);
  		break;
  	case PMBUS_PIN_OP_WARN_LIMIT:
  		word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
  		ret = pmbus_write_word_data(client, 0,
  					    LM25066_MFR_PIN_OP_WARN_LIMIT,
  					    word);
  		break;
  	case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
  		/* Adjust from VIN coefficients (for LM25056) */
  		word = DIV_ROUND_CLOSEST((int)word * 6140, 293);
  		word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
  		ret = pmbus_write_word_data(client, 0,
  					    LM25056_VAUX_UV_WARN_LIMIT, word);
  		break;
  	case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
  		/* Adjust from VIN coefficients (for LM25056) */
  		word = DIV_ROUND_CLOSEST((int)word * 6140, 293);
  		word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
  		ret = pmbus_write_word_data(client, 0,
  					    LM25056_VAUX_OV_WARN_LIMIT, word);
  		break;
  	case PMBUS_VIRT_RESET_PIN_HISTORY:
  		ret = pmbus_write_byte(client, 0, LM25066_CLEAR_PIN_PEAK);
  		break;
  	case PMBUS_VIRT_SAMPLES:
  		word = clamp_val(word, 1, LM25066_SAMPLES_FOR_AVG_MAX);
  		ret = pmbus_write_byte_data(client, 0, LM25066_SAMPLES_FOR_AVG,
  					    ilog2(word));
  		break;
  	default:
  		ret = -ENODATA;
  		break;
  	}
  	return ret;
  }
  
  static int lm25066_probe(struct i2c_client *client)
  {
  	int config;
  	struct lm25066_data *data;
  	struct pmbus_driver_info *info;
  	struct __coeff *coeff;
  
  	if (!i2c_check_functionality(client->adapter,
  				     I2C_FUNC_SMBUS_READ_BYTE_DATA))
  		return -ENODEV;
  
  	data = devm_kzalloc(&client->dev, sizeof(struct lm25066_data),
  			    GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;
  
  	config = i2c_smbus_read_byte_data(client, LM25066_DEVICE_SETUP);
  	if (config < 0)
  		return config;
  
  	data->id = i2c_match_id(lm25066_id, client)->driver_data;
  	info = &data->info;
  
  	info->pages = 1;
  	info->format[PSC_VOLTAGE_IN] = direct;
  	info->format[PSC_VOLTAGE_OUT] = direct;
  	info->format[PSC_CURRENT_IN] = direct;
  	info->format[PSC_TEMPERATURE] = direct;
  	info->format[PSC_POWER] = direct;
  
  	info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VMON
  	  | PMBUS_HAVE_PIN | PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT
  	  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_SAMPLES;
  
  	if (data->id == lm25056) {
  		info->func[0] |= PMBUS_HAVE_STATUS_VMON;
  		info->read_word_data = lm25056_read_word_data;
  		info->read_byte_data = lm25056_read_byte_data;
  		data->rlimit = 0x0fff;
  	} else {
  		info->func[0] |= PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT;
  		info->read_word_data = lm25066_read_word_data;
  		data->rlimit = 0x0fff;
  	}
  	info->write_word_data = lm25066_write_word_data;
  
  	coeff = &lm25066_coeff[data->id][0];
  	info->m[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].m;
  	info->b[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].b;
  	info->R[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].R;
  	info->m[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].m;
  	info->b[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].b;
  	info->R[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].R;
  	info->m[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].m;
  	info->b[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].b;
  	info->R[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].R;
  	info->R[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].R;
  	info->R[PSC_POWER] = coeff[PSC_POWER].R;
  	if (config & LM25066_DEV_SETUP_CL) {
  		info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].m;
  		info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].b;
  		info->m[PSC_POWER] = coeff[PSC_POWER_L].m;
  		info->b[PSC_POWER] = coeff[PSC_POWER_L].b;
  	} else {
  		info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].m;
  		info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].b;
  		info->m[PSC_POWER] = coeff[PSC_POWER].m;
  		info->b[PSC_POWER] = coeff[PSC_POWER].b;
  	}
  
  	return pmbus_do_probe(client, info);
  }
  
  static const struct i2c_device_id lm25066_id[] = {
  	{"lm25056", lm25056},
  	{"lm25066", lm25066},
  	{"lm5064", lm5064},
  	{"lm5066", lm5066},
  	{"lm5066i", lm5066i},
  	{ }
  };
  
  MODULE_DEVICE_TABLE(i2c, lm25066_id);
  
  /* This is the driver that will be inserted */
  static struct i2c_driver lm25066_driver = {
  	.driver = {
  		   .name = "lm25066",
  		   },
  	.probe_new = lm25066_probe,
  	.id_table = lm25066_id,
  };
  
  module_i2c_driver(lm25066_driver);
  
  MODULE_AUTHOR("Guenter Roeck");
  MODULE_DESCRIPTION("PMBus driver for LM25066 and compatible chips");
  MODULE_LICENSE("GPL");
  MODULE_IMPORT_NS(PMBUS);
  