hw/sensor/dps310.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2017-2021 Joel Stanley <joel@jms.id.au>, IBM Corporation
   4  *
   5  * Infineon DPS310 temperature and humidity sensor
   6  *
   7  * https://www.infineon.com/cms/en/product/sensor/pressure-sensors/pressure-sensors-for-iot/dps310/
   8  */
   9
  10 #include "qemu/osdep.h"
  11 #include "qemu/log.h"
  12 #include "hw/i2c/i2c.h"
  13 #include "qapi/error.h"
  14 #include "qapi/visitor.h"
  15 #include "migration/vmstate.h"
  16
  17 #define NUM_REGISTERS   0x33
  18
  19 typedef struct DPS310State {
  20     /*< private >*/
  21     I2CSlave i2c;
  22
  23     /*< public >*/
  24     uint8_t regs[NUM_REGISTERS];
  25
  26     uint8_t len;
  27     uint8_t pointer;
  28
  29 } DPS310State;
  30
  31 #define TYPE_DPS310 "dps310"
  32 #define DPS310(obj) OBJECT_CHECK(DPS310State, (obj), TYPE_DPS310)
  33
  34 #define DPS310_PRS_B2           0x00
  35 #define DPS310_PRS_B1           0x01
  36 #define DPS310_PRS_B0           0x02
  37 #define DPS310_TMP_B2           0x03
  38 #define DPS310_TMP_B1           0x04
  39 #define DPS310_TMP_B0           0x05
  40 #define DPS310_PRS_CFG          0x06
  41 #define DPS310_TMP_CFG          0x07
  42 #define  DPS310_TMP_RATE_BITS   (0x70)
  43 #define DPS310_MEAS_CFG         0x08
  44 #define  DPS310_MEAS_CTRL_BITS  (0x07)
  45 #define   DPS310_PRESSURE_EN    BIT(0)
  46 #define   DPS310_TEMP_EN        BIT(1)
  47 #define   DPS310_BACKGROUND     BIT(2)
  48 #define  DPS310_PRS_RDY         BIT(4)
  49 #define  DPS310_TMP_RDY         BIT(5)
  50 #define  DPS310_SENSOR_RDY      BIT(6)
  51 #define  DPS310_COEF_RDY        BIT(7)
  52 #define DPS310_CFG_REG          0x09
  53 #define DPS310_RESET            0x0c
  54 #define  DPS310_RESET_MAGIC     (BIT(0) | BIT(3))
  55 #define DPS310_COEF_BASE        0x10
  56 #define DPS310_COEF_LAST        0x21
  57 #define DPS310_COEF_SRC         0x28
  58
  59 static void dps310_reset(DeviceState *dev)
  60 {
  61     DPS310State *s = DPS310(dev);
  62
  63     static const uint8_t regs_reset_state[sizeof(s->regs)] = {
  64         0xfe, 0x2f, 0xee, 0x02, 0x69, 0xa6, 0x00, 0x80, 0xc7, 0x00, 0x00, 0x00,
  65         0x00, 0x10, 0x00, 0x00, 0x0e, 0x1e, 0xdd, 0x13, 0xca, 0x5f, 0x21, 0x52,
  66         0xf9, 0xc6, 0x04, 0xd1, 0xdb, 0x47, 0x00, 0x5b, 0xfb, 0x3a, 0x00, 0x00,
  67         0x20, 0x49, 0x4e, 0xa5, 0x90, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  68         0x60, 0x15, 0x02
  69     };
  70
  71     memcpy(s->regs, regs_reset_state, sizeof(s->regs));
  72     s->pointer = 0;
  73
  74     /* TODO: assert these after some timeout ? */
  75     s->regs[DPS310_MEAS_CFG] = DPS310_COEF_RDY | DPS310_SENSOR_RDY
  76         | DPS310_TMP_RDY | DPS310_PRS_RDY;
  77 }
  78
  79 static uint8_t dps310_read(DPS310State *s, uint8_t reg)
  80 {
  81     if (reg >= sizeof(s->regs)) {
  82         qemu_log_mask(LOG_GUEST_ERROR, "%s: register 0x%02x out of bounds\n",
  83                       __func__, s->pointer);
  84         return 0xFF;
  85     }
  86
  87     switch (reg) {
  88     case DPS310_PRS_B2:
  89     case DPS310_PRS_B1:
  90     case DPS310_PRS_B0:
  91     case DPS310_TMP_B2:
  92     case DPS310_TMP_B1:
  93     case DPS310_TMP_B0:
  94     case DPS310_PRS_CFG:
  95     case DPS310_TMP_CFG:
  96     case DPS310_MEAS_CFG:
  97     case DPS310_CFG_REG:
  98     case DPS310_COEF_BASE...DPS310_COEF_LAST:
  99     case DPS310_COEF_SRC:
 100     case 0x32: /* Undocumented register to indicate workaround not required */
 101         return s->regs[reg];
 102     default:
 103         qemu_log_mask(LOG_UNIMP, "%s: register 0x%02x unimplemented\n",
 104                       __func__, reg);
 105         return 0xFF;
 106     }
 107 }
 108
 109 static void dps310_write(DPS310State *s, uint8_t reg, uint8_t data)
 110 {
 111     if (reg >= sizeof(s->regs)) {
 112         qemu_log_mask(LOG_GUEST_ERROR, "%s: register %d out of bounds\n",
 113                       __func__, s->pointer);
 114         return;
 115     }
 116
 117     switch (reg) {
 118     case DPS310_RESET:
 119         if (data == DPS310_RESET_MAGIC) {
 120             device_cold_reset(DEVICE(s));
 121         }
 122         break;
 123     case DPS310_PRS_CFG:
 124     case DPS310_TMP_CFG:
 125     case DPS310_MEAS_CFG:
 126     case DPS310_CFG_REG:
 127         s->regs[reg] = data;
 128         break;
 129     default:
 130         qemu_log_mask(LOG_UNIMP, "%s: register 0x%02x unimplemented\n",
 131                       __func__, reg);
 132         return;
 133     }
 134 }
 135
 136 static uint8_t dps310_rx(I2CSlave *i2c)
 137 {
 138     DPS310State *s = DPS310(i2c);
 139
 140     if (s->len == 1) {
 141         return dps310_read(s, s->pointer++);
 142     } else {
 143         return 0xFF;
 144     }
 145 }
 146
 147 static int dps310_tx(I2CSlave *i2c, uint8_t data)
 148 {
 149     DPS310State *s = DPS310(i2c);
 150
 151     if (s->len == 0) {
 152         /*
 153          * first byte is the register pointer for a read or write
 154          * operation
 155          */
 156         s->pointer = data;
 157         s->len++;
 158     } else if (s->len == 1) {
 159         dps310_write(s, s->pointer++, data);
 160     }
 161
 162     return 0;
 163 }
 164
 165 static int dps310_event(I2CSlave *i2c, enum i2c_event event)
 166 {
 167     DPS310State *s = DPS310(i2c);
 168
 169     switch (event) {
 170     case I2C_START_SEND:
 171         s->pointer = 0xFF;
 172         s->len = 0;
 173         break;
 174     case I2C_START_RECV:
 175         if (s->len != 1) {
 176             qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid recv sequence\n",
 177                           __func__);
 178         }
 179         break;
 180     default:
 181         break;
 182     }
 183
 184     return 0;
 185 }
 186
 187 static const VMStateDescription vmstate_dps310 = {
 188     .name = "DPS310",
 189     .version_id = 0,
 190     .minimum_version_id = 0,
 191     .fields = (VMStateField[]) {
 192         VMSTATE_UINT8(len, DPS310State),
 193         VMSTATE_UINT8_ARRAY(regs, DPS310State, NUM_REGISTERS),
 194         VMSTATE_UINT8(pointer, DPS310State),
 195         VMSTATE_I2C_SLAVE(i2c, DPS310State),
 196         VMSTATE_END_OF_LIST()
 197     }
 198 };
 199
 200 static void dps310_class_init(ObjectClass *klass, void *data)
 201 {
 202     DeviceClass *dc = DEVICE_CLASS(klass);
 203     I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
 204
 205     k->event = dps310_event;
 206     k->recv = dps310_rx;
 207     k->send = dps310_tx;
 208     dc->reset = dps310_reset;
 209     dc->vmsd = &vmstate_dps310;
 210 }
 211
 212 static const TypeInfo dps310_info = {
 213     .name          = TYPE_DPS310,
 214     .parent        = TYPE_I2C_SLAVE,
 215     .instance_size = sizeof(DPS310State),
 216     .class_init    = dps310_class_init,
 217 };
 218
 219 static void dps310_register_types(void)
 220 {
 221     type_register_static(&dps310_info);
 222 }
 223
 224 type_init(dps310_register_types)