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