1 // SPDX-License-Identifier: GPL-2.0-only
3  * mcp4725.c - Support for Microchip MCP4725/6
9  * driver for the Microchip I2C 12-bit digital-to-analog converter (DAC)
10  * (7-bit I2C slave address 0x60, the three LSBs can be configured in
25 #include <linux/iio/dac/mcp4725.h>
55 	outbuf[0] = (data->powerdown_mode + 1) << 4;  in mcp4725_suspend()
57 	data->powerdown = true;  in mcp4725_suspend()
59 	ret = i2c_master_send(data->client, outbuf, 2);  in mcp4725_suspend()
63 		return -EIO;  in mcp4725_suspend()
74 	/* restore previous DAC value */  in mcp4725_resume()
75 	outbuf[0] = (data->dac_value >> 8) & 0xf;  in mcp4725_resume()
76 	outbuf[1] = data->dac_value & 0xff;  in mcp4725_resume()
77 	data->powerdown = false;  in mcp4725_resume()
79 	ret = i2c_master_send(data->client, outbuf, 2);  in mcp4725_resume()
83 		return -EIO;  in mcp4725_resume()
107 	inoutbuf[0] |= data->ref_mode << 3;  in mcp4725_store_eeprom()
108 	inoutbuf[0] |= data->powerdown ? ((data->powerdown_mode + 1) << 1) : 0;  in mcp4725_store_eeprom()
109 	inoutbuf[1] = data->dac_value >> 4;  in mcp4725_store_eeprom()
110 	inoutbuf[2] = (data->dac_value & 0xf) << 4;  in mcp4725_store_eeprom()
112 	ret = i2c_master_send(data->client, inoutbuf, 3);  in mcp4725_store_eeprom()
116 		return -EIO;  in mcp4725_store_eeprom()
119 	while (tries--) {  in mcp4725_store_eeprom()
121 		ret = i2c_master_recv(data->client, inoutbuf, 3);  in mcp4725_store_eeprom()
125 			return -EIO;  in mcp4725_store_eeprom()
132 		dev_err(&data->client->dev,  in mcp4725_store_eeprom()
134 		return -EIO;  in mcp4725_store_eeprom()
168 	return data->powerdown_mode;  in mcp4725_get_powerdown_mode()
172 	const struct iio_chan_spec *chan, unsigned mode)  in mcp4725_set_powerdown_mode()  argument
176 	data->powerdown_mode = mode;  in mcp4725_set_powerdown_mode()
186 	return sysfs_emit(buf, "%d\n", data->powerdown);  in mcp4725_read_powerdown()
202 		ret = mcp4725_suspend(&data->client->dev);  in mcp4725_write_powerdown()
204 		ret = mcp4725_resume(&data->client->dev);  in mcp4725_write_powerdown()
287 		return -EINVAL;  in mcp4725_set_value()
292 	ret = i2c_master_send(data->client, outbuf, 2);  in mcp4725_set_value()
296 		return -EIO;  in mcp4725_set_value()
308 	outbuf[0] |= data->ref_mode << 3;  in mcp4726_set_cfg()
309 	if (data->powerdown)  in mcp4726_set_cfg()
310 		outbuf[0] |= data->powerdown << 1;  in mcp4726_set_cfg()
311 	outbuf[1] = data->dac_value >> 4;  in mcp4726_set_cfg()
312 	outbuf[2] = (data->dac_value & 0xf) << 4;  in mcp4726_set_cfg()
314 	ret = i2c_master_send(data->client, outbuf, 3);  in mcp4726_set_cfg()
318 		return -EIO;  in mcp4726_set_cfg()
325 			   int *val, int *val2, long mask)  in mcp4725_read_raw()  argument
330 	switch (mask) {  in mcp4725_read_raw()
332 		*val = data->dac_value;  in mcp4725_read_raw()
335 		if (data->ref_mode == MCP472X_REF_VDD)  in mcp4725_read_raw()
336 			ret = regulator_get_voltage(data->vdd_reg);  in mcp4725_read_raw()
338 			ret = regulator_get_voltage(data->vref_reg);  in mcp4725_read_raw()
347 	return -EINVAL;  in mcp4725_read_raw()
352 			       int val, int val2, long mask)  in mcp4725_write_raw()  argument
357 	switch (mask) {  in mcp4725_write_raw()
360 		data->dac_value = val;  in mcp4725_write_raw()
363 		ret = -EINVAL;  in mcp4725_write_raw()
379 	/* check if is the vref-supply defined */  in mcp4725_probe_dt()
380 	pdata->use_vref = device_property_present(dev, "vref-supply");  in mcp4725_probe_dt()
381 	pdata->vref_buffered =  in mcp4725_probe_dt()
382 		device_property_read_bool(dev, "microchip,vref-buffered");  in mcp4725_probe_dt()
399 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));  in mcp4725_probe()
401 		return -ENOMEM;  in mcp4725_probe()
404 	data->client = client;  in mcp4725_probe()
406 	pdata = dev_get_platdata(&client->dev);  in mcp4725_probe()
409 		err = mcp4725_probe_dt(&client->dev, &pdata_dt);  in mcp4725_probe()
411 			dev_err(&client->dev,  in mcp4725_probe()
418 	if (info->use_ext_ref_voltage && pdata->use_vref) {  in mcp4725_probe()
419 		dev_err(&client->dev,  in mcp4725_probe()
421 		return -EINVAL;  in mcp4725_probe()
424 	if (!pdata->use_vref && pdata->vref_buffered) {  in mcp4725_probe()
425 		dev_err(&client->dev,  in mcp4725_probe()
427 		return -EINVAL;  in mcp4725_probe()
430 	if (!pdata->use_vref)  in mcp4725_probe()
431 		data->ref_mode = MCP472X_REF_VDD;  in mcp4725_probe()
433 		data->ref_mode = pdata->vref_buffered ?  in mcp4725_probe()
437 	data->vdd_reg = devm_regulator_get(&client->dev, "vdd");  in mcp4725_probe()
438 	if (IS_ERR(data->vdd_reg))  in mcp4725_probe()
439 		return PTR_ERR(data->vdd_reg);  in mcp4725_probe()
441 	err = regulator_enable(data->vdd_reg);  in mcp4725_probe()
445 	if (pdata->use_vref) {  in mcp4725_probe()
446 		data->vref_reg = devm_regulator_get(&client->dev, "vref");  in mcp4725_probe()
447 		if (IS_ERR(data->vref_reg)) {  in mcp4725_probe()
448 			err = PTR_ERR(data->vref_reg);  in mcp4725_probe()
452 		err = regulator_enable(data->vref_reg);  in mcp4725_probe()
457 	indio_dev->name = id->name;  in mcp4725_probe()
458 	indio_dev->info = &mcp4725_info;  in mcp4725_probe()
459 	indio_dev->channels = info->chan_spec;  in mcp4725_probe()
460 	indio_dev->num_channels = 1;  in mcp4725_probe()
461 	indio_dev->modes = INDIO_DIRECT_MODE;  in mcp4725_probe()
463 	/* read current DAC value and settings */  in mcp4725_probe()
464 	err = i2c_master_recv(client, inbuf, info->dac_reg_offset);  in mcp4725_probe()
467 		dev_err(&client->dev, "failed to read DAC value");  in mcp4725_probe()
471 	data->powerdown = pd > 0;  in mcp4725_probe()
472 	data->powerdown_mode = pd ? pd - 1 : 2; /* largest resistor to gnd */  in mcp4725_probe()
473 	data->dac_value = (inbuf[1] << 4) | (inbuf[2] >> 4);  in mcp4725_probe()
474 	if (!info->use_ext_ref_voltage)  in mcp4725_probe()
477 	if (!info->use_ext_ref_voltage && ref != data->ref_mode) {  in mcp4725_probe()
478 		dev_info(&client->dev,  in mcp4725_probe()
479 			"voltage reference mode differs (conf: %u, eeprom: %u), setting %u",  in mcp4725_probe()
480 			data->ref_mode, ref, data->ref_mode);  in mcp4725_probe()
493 	if (data->vref_reg)  in mcp4725_probe()
494 		regulator_disable(data->vref_reg);  in mcp4725_probe()
497 	regulator_disable(data->vdd_reg);  in mcp4725_probe()
509 	if (data->vref_reg)  in mcp4725_remove()
510 		regulator_disable(data->vref_reg);  in mcp4725_remove()
511 	regulator_disable(data->vdd_reg);  in mcp4725_remove()
558 MODULE_DESCRIPTION("MCP4725/6 12-bit DAC");