1 // SPDX-License-Identifier: GPL-2.0+ 2 // 3 // Copyright (c) 2010-2024 Analog Devices Inc. 4 // Copyright (c) 2024 Baylibre, SAS 5 6 #include <linux/bitfield.h> 7 #include <linux/device.h> 8 #include <linux/module.h> 9 #include <linux/property.h> 10 #include <linux/regulator/consumer.h> 11 12 #include "ad3552r.h" 13 14 static const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2] = { 15 [AD3552R_CH_OUTPUT_RANGE_0__2P5V] = { 0, 2500 }, 16 [AD3552R_CH_OUTPUT_RANGE_0__5V] = { 0, 5000 }, 17 [AD3552R_CH_OUTPUT_RANGE_0__10V] = { 0, 10000 }, 18 [AD3552R_CH_OUTPUT_RANGE_NEG_5__5V] = { -5000, 5000 }, 19 [AD3552R_CH_OUTPUT_RANGE_NEG_10__10V] = { -10000, 10000 } 20 }; 21 22 static const s32 ad3542r_ch_ranges[AD3542R_MAX_RANGES][2] = { 23 [AD3542R_CH_OUTPUT_RANGE_0__2P5V] = { 0, 2500 }, 24 [AD3542R_CH_OUTPUT_RANGE_0__5V] = { 0, 5000 }, 25 [AD3542R_CH_OUTPUT_RANGE_0__10V] = { 0, 10000 }, 26 [AD3542R_CH_OUTPUT_RANGE_NEG_5__5V] = { -5000, 5000 }, 27 [AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V] = { -2500, 7500 } 28 }; 29 30 /* Gain * AD3552R_GAIN_SCALE */ 31 static const s32 gains_scaling_table[] = { 32 [AD3552R_CH_GAIN_SCALING_1] = 1000, 33 [AD3552R_CH_GAIN_SCALING_0_5] = 500, 34 [AD3552R_CH_GAIN_SCALING_0_25] = 250, 35 [AD3552R_CH_GAIN_SCALING_0_125] = 125 36 }; 37 38 const struct ad3552r_model_data ad3541r_model_data = { 39 .model_name = "ad3541r", 40 .chip_id = AD3541R_ID, 41 .num_hw_channels = 1, 42 .ranges_table = ad3542r_ch_ranges, 43 .num_ranges = ARRAY_SIZE(ad3542r_ch_ranges), 44 .requires_output_range = true, 45 .num_spi_data_lanes = 2, 46 }; 47 EXPORT_SYMBOL_NS_GPL(ad3541r_model_data, "IIO_AD3552R"); 48 49 const struct ad3552r_model_data ad3542r_model_data = { 50 .model_name = "ad3542r", 51 .chip_id = AD3542R_ID, 52 .num_hw_channels = 2, 53 .ranges_table = ad3542r_ch_ranges, 54 .num_ranges = ARRAY_SIZE(ad3542r_ch_ranges), 55 .requires_output_range = true, 56 .num_spi_data_lanes = 2, 57 }; 58 EXPORT_SYMBOL_NS_GPL(ad3542r_model_data, "IIO_AD3552R"); 59 60 const struct ad3552r_model_data ad3551r_model_data = { 61 .model_name = "ad3551r", 62 .chip_id = AD3551R_ID, 63 .num_hw_channels = 1, 64 .ranges_table = ad3552r_ch_ranges, 65 .num_ranges = ARRAY_SIZE(ad3552r_ch_ranges), 66 .requires_output_range = false, 67 .num_spi_data_lanes = 4, 68 }; 69 EXPORT_SYMBOL_NS_GPL(ad3551r_model_data, "IIO_AD3552R"); 70 71 const struct ad3552r_model_data ad3552r_model_data = { 72 .model_name = "ad3552r", 73 .chip_id = AD3552R_ID, 74 .num_hw_channels = 2, 75 .ranges_table = ad3552r_ch_ranges, 76 .num_ranges = ARRAY_SIZE(ad3552r_ch_ranges), 77 .requires_output_range = false, 78 .num_spi_data_lanes = 4, 79 }; 80 EXPORT_SYMBOL_NS_GPL(ad3552r_model_data, "IIO_AD3552R"); 81 82 u16 ad3552r_calc_custom_gain(u8 p, u8 n, s16 goffs) 83 { 84 return FIELD_PREP(AD3552R_MASK_CH_RANGE_OVERRIDE, 1) | 85 FIELD_PREP(AD3552R_MASK_CH_GAIN_SCALING_P, p) | 86 FIELD_PREP(AD3552R_MASK_CH_GAIN_SCALING_N, n) | 87 FIELD_PREP(AD3552R_MASK_CH_OFFSET_BIT_8, abs(goffs)) | 88 FIELD_PREP(AD3552R_MASK_CH_OFFSET_POLARITY, goffs < 0); 89 } 90 EXPORT_SYMBOL_NS_GPL(ad3552r_calc_custom_gain, "IIO_AD3552R"); 91 92 static void ad3552r_get_custom_range(struct ad3552r_ch_data *ch_data, 93 s32 *v_min, s32 *v_max) 94 { 95 s64 vref, tmp, common, offset, gn, gp; 96 /* 97 * From datasheet formula (In Volts): 98 * Vmin = 2.5 + [(GainN + Offset / 1024) * 2.5 * Rfb * 1.03] 99 * Vmax = 2.5 - [(GainP + Offset / 1024) * 2.5 * Rfb * 1.03] 100 * Calculus are converted to milivolts 101 */ 102 vref = 2500; 103 /* 2.5 * 1.03 * 1000 (To mV) */ 104 common = 2575 * ch_data->rfb; 105 offset = ch_data->gain_offset; 106 107 gn = gains_scaling_table[ch_data->n]; 108 tmp = (1024 * gn + AD3552R_GAIN_SCALE * offset) * common; 109 tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE); 110 *v_max = vref + tmp; 111 112 gp = gains_scaling_table[ch_data->p]; 113 tmp = (1024 * gp - AD3552R_GAIN_SCALE * offset) * common; 114 tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE); 115 *v_min = vref - tmp; 116 } 117 118 void ad3552r_calc_gain_and_offset(struct ad3552r_ch_data *ch_data, 119 const struct ad3552r_model_data *model_data) 120 { 121 s32 idx, v_max, v_min, span, rem; 122 s64 tmp; 123 124 if (ch_data->range_override) { 125 ad3552r_get_custom_range(ch_data, &v_min, &v_max); 126 } else { 127 /* Normal range */ 128 idx = ch_data->range; 129 v_min = model_data->ranges_table[idx][0]; 130 v_max = model_data->ranges_table[idx][1]; 131 } 132 133 /* 134 * From datasheet formula: 135 * Vout = Span * (D / 65536) + Vmin 136 * Converted to scale and offset: 137 * Scale = Span / 65536 138 * Offset = 65536 * Vmin / Span 139 * 140 * Reminders are in micros in order to be printed as 141 * IIO_VAL_INT_PLUS_MICRO 142 */ 143 span = v_max - v_min; 144 ch_data->scale_int = div_s64_rem(span, 65536, &rem); 145 /* Do operations in microvolts */ 146 ch_data->scale_dec = DIV_ROUND_CLOSEST((s64)rem * 1000000, 65536); 147 148 ch_data->offset_int = div_s64_rem(v_min * 65536, span, &rem); 149 tmp = (s64)rem * 1000000; 150 ch_data->offset_dec = div_s64(tmp, span); 151 } 152 EXPORT_SYMBOL_NS_GPL(ad3552r_calc_gain_and_offset, "IIO_AD3552R"); 153 154 int ad3552r_get_ref_voltage(struct device *dev, u32 *val) 155 { 156 int voltage; 157 int delta = 100000; 158 159 voltage = devm_regulator_get_enable_read_voltage(dev, "vref"); 160 if (voltage < 0 && voltage != -ENODEV) 161 return dev_err_probe(dev, voltage, 162 "Error getting vref voltage\n"); 163 164 if (voltage == -ENODEV) { 165 if (device_property_read_bool(dev, "adi,vref-out-en")) 166 *val = AD3552R_INTERNAL_VREF_PIN_2P5V; 167 else 168 *val = AD3552R_INTERNAL_VREF_PIN_FLOATING; 169 170 return 0; 171 } 172 173 if (voltage > 2500000 + delta || voltage < 2500000 - delta) { 174 dev_warn(dev, "vref-supply must be 2.5V"); 175 return -EINVAL; 176 } 177 178 *val = AD3552R_EXTERNAL_VREF_PIN_INPUT; 179 180 return 0; 181 } 182 EXPORT_SYMBOL_NS_GPL(ad3552r_get_ref_voltage, "IIO_AD3552R"); 183 184 int ad3552r_get_drive_strength(struct device *dev, u32 *val) 185 { 186 int err; 187 u32 drive_strength; 188 189 err = device_property_read_u32(dev, "adi,sdo-drive-strength", 190 &drive_strength); 191 if (err) 192 return err; 193 194 if (drive_strength > 3) { 195 dev_err_probe(dev, -EINVAL, 196 "adi,sdo-drive-strength must be less than 4\n"); 197 return -EINVAL; 198 } 199 200 *val = drive_strength; 201 202 return 0; 203 } 204 EXPORT_SYMBOL_NS_GPL(ad3552r_get_drive_strength, "IIO_AD3552R"); 205 206 int ad3552r_get_custom_gain(struct device *dev, struct fwnode_handle *child, 207 u8 *gs_p, u8 *gs_n, u16 *rfb, s16 *goffs) 208 { 209 int err; 210 u32 val; 211 struct fwnode_handle *gain_child __free(fwnode_handle) = 212 fwnode_get_named_child_node(child, 213 "custom-output-range-config"); 214 215 if (!gain_child) 216 return dev_err_probe(dev, -EINVAL, 217 "custom-output-range-config mandatory\n"); 218 219 err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-p", &val); 220 if (err) 221 return dev_err_probe(dev, err, 222 "adi,gain-scaling-p mandatory\n"); 223 *gs_p = val; 224 225 err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-n", &val); 226 if (err) 227 return dev_err_probe(dev, err, 228 "adi,gain-scaling-n property mandatory\n"); 229 *gs_n = val; 230 231 err = fwnode_property_read_u32(gain_child, "adi,rfb-ohms", &val); 232 if (err) 233 return dev_err_probe(dev, err, 234 "adi,rfb-ohms mandatory\n"); 235 *rfb = val; 236 237 err = fwnode_property_read_u32(gain_child, "adi,gain-offset", &val); 238 if (err) 239 return dev_err_probe(dev, err, 240 "adi,gain-offset mandatory\n"); 241 *goffs = val; 242 243 return 0; 244 } 245 EXPORT_SYMBOL_NS_GPL(ad3552r_get_custom_gain, "IIO_AD3552R"); 246 247 static int ad3552r_find_range(const struct ad3552r_model_data *model_info, 248 s32 *vals) 249 { 250 int i; 251 252 for (i = 0; i < model_info->num_ranges; i++) 253 if (vals[0] == model_info->ranges_table[i][0] * 1000 && 254 vals[1] == model_info->ranges_table[i][1] * 1000) 255 return i; 256 257 return -EINVAL; 258 } 259 260 int ad3552r_get_output_range(struct device *dev, 261 const struct ad3552r_model_data *model_info, 262 struct fwnode_handle *child, u32 *val) 263 { 264 int ret; 265 s32 vals[2]; 266 267 /* This property is optional, so returning -ENOENT if missing */ 268 if (!fwnode_property_present(child, "adi,output-range-microvolt")) 269 return -ENOENT; 270 271 ret = fwnode_property_read_u32_array(child, 272 "adi,output-range-microvolt", 273 vals, 2); 274 if (ret) 275 return dev_err_probe(dev, ret, 276 "invalid adi,output-range-microvolt\n"); 277 278 ret = ad3552r_find_range(model_info, vals); 279 if (ret < 0) 280 return dev_err_probe(dev, ret, 281 "invalid adi,output-range-microvolt value\n"); 282 283 *val = ret; 284 285 return 0; 286 } 287 EXPORT_SYMBOL_NS_GPL(ad3552r_get_output_range, "IIO_AD3552R"); 288 289 MODULE_DESCRIPTION("ad3552r common functions"); 290 MODULE_LICENSE("GPL"); 291