1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * The GE HealthCare PMC ADC is a 16-Channel (Voltage and current), 16-Bit 4 * ADC with an I2C Interface. 5 * 6 * Copyright (C) 2024, GE HealthCare 7 * 8 * Authors: 9 * Herve Codina <herve.codina@bootlin.com> 10 */ 11 #include <dt-bindings/iio/adc/gehc,pmc-adc.h> 12 #include <linux/bitops.h> 13 #include <linux/clk.h> 14 #include <linux/i2c.h> 15 #include <linux/iio/iio.h> 16 #include <linux/module.h> 17 #include <linux/regulator/consumer.h> 18 #include <linux/slab.h> 19 20 struct pmc_adc { 21 struct i2c_client *client; 22 }; 23 24 #define PMC_ADC_CMD_REQUEST_PROTOCOL_VERSION 0x01 25 #define PMC_ADC_CMD_READ_VOLTAGE(_ch) (0x10 | (_ch)) 26 #define PMC_ADC_CMD_READ_CURRENT(_ch) (0x20 | (_ch)) 27 28 #define PMC_ADC_VOLTAGE_CHANNEL(_ch, _ds_name) { \ 29 .type = IIO_VOLTAGE, \ 30 .indexed = 1, \ 31 .channel = (_ch), \ 32 .address = PMC_ADC_CMD_READ_VOLTAGE(_ch), \ 33 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ 34 .datasheet_name = (_ds_name), \ 35 } 36 37 #define PMC_ADC_CURRENT_CHANNEL(_ch, _ds_name) { \ 38 .type = IIO_CURRENT, \ 39 .indexed = 1, \ 40 .channel = (_ch), \ 41 .address = PMC_ADC_CMD_READ_CURRENT(_ch), \ 42 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ 43 .datasheet_name = (_ds_name), \ 44 } 45 46 static const struct iio_chan_spec pmc_adc_channels[] = { 47 PMC_ADC_VOLTAGE_CHANNEL(0, "CH0_V"), 48 PMC_ADC_VOLTAGE_CHANNEL(1, "CH1_V"), 49 PMC_ADC_VOLTAGE_CHANNEL(2, "CH2_V"), 50 PMC_ADC_VOLTAGE_CHANNEL(3, "CH3_V"), 51 PMC_ADC_VOLTAGE_CHANNEL(4, "CH4_V"), 52 PMC_ADC_VOLTAGE_CHANNEL(5, "CH5_V"), 53 PMC_ADC_VOLTAGE_CHANNEL(6, "CH6_V"), 54 PMC_ADC_VOLTAGE_CHANNEL(7, "CH7_V"), 55 PMC_ADC_VOLTAGE_CHANNEL(8, "CH8_V"), 56 PMC_ADC_VOLTAGE_CHANNEL(9, "CH9_V"), 57 PMC_ADC_VOLTAGE_CHANNEL(10, "CH10_V"), 58 PMC_ADC_VOLTAGE_CHANNEL(11, "CH11_V"), 59 PMC_ADC_VOLTAGE_CHANNEL(12, "CH12_V"), 60 PMC_ADC_VOLTAGE_CHANNEL(13, "CH13_V"), 61 PMC_ADC_VOLTAGE_CHANNEL(14, "CH14_V"), 62 PMC_ADC_VOLTAGE_CHANNEL(15, "CH15_V"), 63 64 PMC_ADC_CURRENT_CHANNEL(0, "CH0_I"), 65 PMC_ADC_CURRENT_CHANNEL(1, "CH1_I"), 66 PMC_ADC_CURRENT_CHANNEL(2, "CH2_I"), 67 PMC_ADC_CURRENT_CHANNEL(3, "CH3_I"), 68 PMC_ADC_CURRENT_CHANNEL(4, "CH4_I"), 69 PMC_ADC_CURRENT_CHANNEL(5, "CH5_I"), 70 PMC_ADC_CURRENT_CHANNEL(6, "CH6_I"), 71 PMC_ADC_CURRENT_CHANNEL(7, "CH7_I"), 72 PMC_ADC_CURRENT_CHANNEL(8, "CH8_I"), 73 PMC_ADC_CURRENT_CHANNEL(9, "CH9_I"), 74 PMC_ADC_CURRENT_CHANNEL(10, "CH10_I"), 75 PMC_ADC_CURRENT_CHANNEL(11, "CH11_I"), 76 PMC_ADC_CURRENT_CHANNEL(12, "CH12_I"), 77 PMC_ADC_CURRENT_CHANNEL(13, "CH13_I"), 78 PMC_ADC_CURRENT_CHANNEL(14, "CH14_I"), 79 PMC_ADC_CURRENT_CHANNEL(15, "CH15_I"), 80 }; 81 82 static int pmc_adc_read_raw_ch(struct pmc_adc *pmc_adc, u8 cmd, int *val) 83 { 84 s32 ret; 85 86 ret = i2c_smbus_read_word_swapped(pmc_adc->client, cmd); 87 if (ret < 0) { 88 dev_err(&pmc_adc->client->dev, "i2c read word failed (%d)\n", ret); 89 return ret; 90 } 91 92 *val = sign_extend32(ret, 15); 93 return 0; 94 } 95 96 static int pmc_adc_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, 97 int *val, int *val2, long mask) 98 { 99 struct pmc_adc *pmc_adc = iio_priv(indio_dev); 100 int ret; 101 102 switch (mask) { 103 case IIO_CHAN_INFO_PROCESSED: 104 /* Values are directly read in mV or mA */ 105 ret = pmc_adc_read_raw_ch(pmc_adc, chan->address, val); 106 if (ret) 107 return ret; 108 return IIO_VAL_INT; 109 } 110 111 return -EINVAL; 112 } 113 114 static int pmc_adc_fwnode_xlate(struct iio_dev *indio_dev, 115 const struct fwnode_reference_args *iiospec) 116 { 117 enum iio_chan_type expected_type; 118 unsigned int i; 119 120 /* 121 * args[0]: Acquisition type (i.e. voltage or current) 122 * args[1]: PMC ADC channel number 123 */ 124 if (iiospec->nargs != 2) 125 return -EINVAL; 126 127 switch (iiospec->args[0]) { 128 case GEHC_PMC_ADC_VOLTAGE: 129 expected_type = IIO_VOLTAGE; 130 break; 131 case GEHC_PMC_ADC_CURRENT: 132 expected_type = IIO_CURRENT; 133 break; 134 default: 135 dev_err(&indio_dev->dev, "Invalid channel type %llu\n", 136 iiospec->args[0]); 137 return -EINVAL; 138 } 139 140 for (i = 0; i < indio_dev->num_channels; i++) 141 if (indio_dev->channels[i].type == expected_type && 142 indio_dev->channels[i].channel == iiospec->args[1]) 143 return i; 144 145 dev_err(&indio_dev->dev, "Invalid channel type %llu number %llu\n", 146 iiospec->args[0], iiospec->args[1]); 147 return -EINVAL; 148 } 149 150 static const struct iio_info pmc_adc_info = { 151 .read_raw = pmc_adc_read_raw, 152 .fwnode_xlate = pmc_adc_fwnode_xlate, 153 }; 154 155 static const char *const pmc_adc_regulator_names[] = { 156 "vdd", 157 "vdda", 158 "vddio", 159 "vref", 160 }; 161 162 static int pmc_adc_probe(struct i2c_client *client) 163 { 164 struct iio_dev *indio_dev; 165 struct pmc_adc *pmc_adc; 166 struct clk *clk; 167 s32 val; 168 int ret; 169 170 ret = devm_regulator_bulk_get_enable(&client->dev, ARRAY_SIZE(pmc_adc_regulator_names), 171 pmc_adc_regulator_names); 172 if (ret) 173 return dev_err_probe(&client->dev, ret, "Failed to get regulators\n"); 174 175 clk = devm_clk_get_optional_enabled(&client->dev, "osc"); 176 if (IS_ERR(clk)) 177 return dev_err_probe(&client->dev, PTR_ERR(clk), "Failed to get osc clock\n"); 178 179 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*pmc_adc)); 180 if (!indio_dev) 181 return -ENOMEM; 182 183 pmc_adc = iio_priv(indio_dev); 184 pmc_adc->client = client; 185 186 val = i2c_smbus_read_byte_data(pmc_adc->client, PMC_ADC_CMD_REQUEST_PROTOCOL_VERSION); 187 if (val < 0) 188 return dev_err_probe(&client->dev, val, "Failed to get protocol version\n"); 189 190 if (val != 0x01) 191 return dev_err_probe(&client->dev, -EINVAL, 192 "Unsupported protocol version 0x%02x\n", val); 193 194 indio_dev->name = "pmc_adc"; 195 indio_dev->info = &pmc_adc_info; 196 indio_dev->modes = INDIO_DIRECT_MODE; 197 indio_dev->channels = pmc_adc_channels; 198 indio_dev->num_channels = ARRAY_SIZE(pmc_adc_channels); 199 200 return devm_iio_device_register(&client->dev, indio_dev); 201 } 202 203 static const struct of_device_id pmc_adc_of_match[] = { 204 { .compatible = "gehc,pmc-adc"}, 205 { } 206 }; 207 MODULE_DEVICE_TABLE(of, pmc_adc_of_match); 208 209 static const struct i2c_device_id pmc_adc_id_table[] = { 210 { "pmc-adc" }, 211 { } 212 }; 213 MODULE_DEVICE_TABLE(i2c, pmc_adc_id_table); 214 215 static struct i2c_driver pmc_adc_i2c_driver = { 216 .driver = { 217 .name = "pmc-adc", 218 .of_match_table = pmc_adc_of_match, 219 }, 220 .id_table = pmc_adc_id_table, 221 .probe = pmc_adc_probe, 222 }; 223 224 module_i2c_driver(pmc_adc_i2c_driver); 225 226 MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>"); 227 MODULE_DESCRIPTION("GE HealthCare PMC ADC driver"); 228 MODULE_LICENSE("GPL"); 229