1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * isl28022.c - driver for Renesas ISL28022 power monitor chip monitoring
5  * Copyright (c) 2023 Carsten Spieß <mail@carsten-spiess.de>
42 /* shunt ADC settings */
62 /* shunt voltage range */
66 #define ISL28022_PG_40		0x0	/* +/-40 mV */
67 #define ISL28022_PG_80		0x1	/* +/-80 mV */
68 #define ISL28022_PG_160		0x2	/* +/-160 mV */
69 #define ISL28022_PG_320		0x3	/* +/-3200 mV */
84 	u32			shunt;  member
100 			err = regmap_read(data->regmap,  in isl28022_read_in()
108 			return -EOPNOTSUPP;  in isl28022_read_in()
114 			err = regmap_read(data->regmap,  in isl28022_read_in()
118 			switch (data->gain) {  in isl28022_read_in()
121 				*val = (long)((((u16)regval) & 0x7FFF) -  in isl28022_read_in()
126 				*val = (long)((((u16)regval) & 0x3FFF) -  in isl28022_read_in()
131 				*val = (long)((((u16)regval) & 0x1FFF) -  in isl28022_read_in()
136 				*val = (long)((((u16)regval) & 0x0FFF) -  in isl28022_read_in()
142 			return -EOPNOTSUPP;  in isl28022_read_in()
146 		return -EOPNOTSUPP;  in isl28022_read_in()
160 		err = regmap_read(data->regmap,  in isl28022_read_current()
164 		*val = ((long)regval * 1250L * (long)data->gain) /  in isl28022_read_current()
165 			(long)data->shunt;  in isl28022_read_current()
168 		return -EOPNOTSUPP;  in isl28022_read_current()
182 		err = regmap_read(data->regmap,  in isl28022_read_power()
186 		*val = ((51200000L * ((long)data->gain)) /  in isl28022_read_power()
187 			(long)data->shunt) * (long)regval;  in isl28022_read_power()
190 		return -EOPNOTSUPP;  in isl28022_read_power()
207 		return -EOPNOTSUPP;  in isl28022_read()
249 			   HWMON_I_INPUT),	/* channel 1: shunt voltage (mV) */
311 	struct isl28022_data *data = seqf->private;  in shunt_voltage_show()
315 	err = regmap_read(data->regmap,  in shunt_voltage_show()
320 	/* print shunt voltage in micro volt  */  in shunt_voltage_show()
339 	scnprintf(name, sizeof(name), "%d-%04hx", client->adapter->nr, client->addr);  in isl28022_debugfs_init()
344 	devm_add_action_or_reset(&client->dev, isl28022_debugfs_remove, debugfs);  in isl28022_debugfs_init()
350  * following values for shunt range and resistor are allowed:
351  *   40 mV -> gain 1, shunt min.  800 micro ohms
352  *   80 mV -> gain 2, shunt min. 1600 micro ohms
353  *  160 mV -> gain 4, shunt min. 3200 micro ohms
354  *  320 mV -> gain 8, shunt min. 6400 micro ohms
361 	err = device_property_read_u32(dev, "shunt-resistor-micro-ohms", &val);  in isl28022_read_properties()
362 	if (err == -EINVAL)  in isl28022_read_properties()
366 	data->shunt = val;  in isl28022_read_properties()
368 	err = device_property_read_u32(dev, "renesas,shunt-range-microvolt", &val);  in isl28022_read_properties()
369 	if (err == -EINVAL)  in isl28022_read_properties()
376 		data->gain = 1;  in isl28022_read_properties()
377 		if (data->shunt < 800)  in isl28022_read_properties()
381 		data->gain = 2;  in isl28022_read_properties()
382 		if (data->shunt < 1600)  in isl28022_read_properties()
386 		data->gain = 4;  in isl28022_read_properties()
387 		if (data->shunt < 3200)  in isl28022_read_properties()
391 		data->gain = 8;  in isl28022_read_properties()
392 		if (data->shunt < 6400)  in isl28022_read_properties()
396 		return dev_err_probe(dev, -EINVAL,  in isl28022_read_properties()
397 				     "renesas,shunt-range-microvolt invalid value %d\n",  in isl28022_read_properties()
401 	err = device_property_read_u32(dev, "renesas,average-samples", &val);  in isl28022_read_properties()
402 	if (err == -EINVAL)  in isl28022_read_properties()
407 		return dev_err_probe(dev, -EINVAL,  in isl28022_read_properties()
408 				     "renesas,average-samples invalid value %d\n",  in isl28022_read_properties()
411 	data->average = val;  in isl28022_read_properties()
416 	return dev_err_probe(dev, -EINVAL,  in isl28022_read_properties()
417 			     "renesas,shunt-resistor-microvolt invalid value %d\n",  in isl28022_read_properties()
418 			     data->shunt);  in isl28022_read_properties()
424  * The driver supports only shunt and bus continuous ADC mode at 15bit resolution
426  * Shunt voltage gain 1,2,4 or 8 is allowed.
437 			(__ffs(data->gain) << ISL28022_PG_SHIFT) |  in isl28022_config()
438 			((ISL28022_ADC_15_1 + __ffs(data->average)) << ISL28022_SADC_SHIFT) |  in isl28022_config()
439 			((ISL28022_ADC_15_1 + __ffs(data->average)) << ISL28022_BADC_SHIFT);  in isl28022_config()
441 	calib = data->shunt ? 0x8000 / data->gain : 0;  in isl28022_config()
443 	err = regmap_write(data->regmap, ISL28022_REG_CONFIG, config);  in isl28022_config()
447 	return regmap_write(data->regmap, ISL28022_REG_CALIB, calib);  in isl28022_config()
452 	struct device *dev = &client->dev;  in isl28022_probe()
457 	if (!i2c_check_functionality(client->adapter,  in isl28022_probe()
460 		return -ENODEV;  in isl28022_probe()
464 		return -ENOMEM;  in isl28022_probe()
470 	data->regmap = devm_regmap_init_i2c(client, &isl28022_regmap_config);  in isl28022_probe()
471 	if (IS_ERR(data->regmap))  in isl28022_probe()
472 		return PTR_ERR(data->regmap);  in isl28022_probe()
480 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,  in isl28022_probe()
530 MODULE_AUTHOR("Carsten Spieß <mail@carsten-spiess.de>");