Harald Welte | c3f170d | 2019-02-24 09:06:59 +0100 | [diff] [blame] | 1 | /* Access functions for the per-SIM-slot NCN8025 chip card interface, |
| 2 | * which is controlled via (half) a SX1503 I2C GPIO expander. |
| 3 | * |
| 4 | * (C) 2019 by Harald Welte <laforge@gnumonks.org> |
| 5 | * |
| 6 | * SPDX-License-Identifier: GPL-2.0-or-later |
| 7 | */ |
| 8 | |
| 9 | #include <stdint.h> |
| 10 | #include <string.h> |
| 11 | #include <utils_assert.h> |
| 12 | #include <utils.h> |
| 13 | #include "octsim_i2c.h" |
| 14 | #include "ncn8025.h" |
| 15 | |
| 16 | #define SX1503_ADDR 0x20 |
| 17 | |
| 18 | /*! translate from ncn8025_settings into SX1503 register value */ |
| 19 | static uint8_t ncn8025_encode(const struct ncn8025_settings *set) |
| 20 | { |
| 21 | uint8_t reg = 0; |
| 22 | if (set->rstin) |
| 23 | reg |= 0x01; |
| 24 | if (!set->cmdvcc) |
| 25 | reg |= 0x02; |
| 26 | if (set->clkdiv & 1) |
| 27 | reg |= 0x04; |
| 28 | if (set->clkdiv & 2) |
| 29 | reg |= 0x08; |
| 30 | if (set->vsel & 1) |
| 31 | reg |= 0x10; |
| 32 | if (set->vsel & 2) |
| 33 | reg |= 0x20; |
| 34 | if (set->led) |
| 35 | reg |= 0x80; |
| 36 | return reg; |
| 37 | } |
| 38 | |
| 39 | /*! translate from register value to ncn8025_settings */ |
| 40 | static int ncn8025_decode(uint8_t reg, struct ncn8025_settings *set) |
| 41 | { |
| 42 | memset(set, 0, sizeof(*set)); |
| 43 | |
| 44 | if (reg & 0x01) |
| 45 | set->rstin = true; |
| 46 | if (!(reg & 0x02)) |
| 47 | set->cmdvcc = true; |
| 48 | if (reg & 0x04) |
| 49 | set->clkdiv |= 0x01; |
| 50 | if (reg & 0x08) |
| 51 | set->clkdiv |= 0x02; |
| 52 | if (reg & 0x10) |
| 53 | set->vsel |= 0x01; |
| 54 | if (reg & 0x20) |
| 55 | set->vsel |= 0x02; |
| 56 | if (!(reg & 0x40)) |
| 57 | set->simpres = true; |
| 58 | if ((reg & 0x80)) |
| 59 | set->led = true; |
| 60 | |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | static const struct i2c_adapter *slot2adapter(unsigned int slot) |
| 65 | { |
| 66 | unsigned int idx = slot / 2; |
| 67 | ASSERT(idx < ARRAY_SIZE(i2c)); |
| 68 | return &i2c[idx]; |
| 69 | } |
| 70 | |
| 71 | |
| 72 | static const uint8_t slot2data_reg(unsigned int slot) |
| 73 | { |
| 74 | if (slot & 1) |
| 75 | return 0x00; |
| 76 | else |
| 77 | return 0x01; |
| 78 | } |
| 79 | |
| 80 | static const uint8_t slot2dir_reg(unsigned int slot) |
| 81 | { |
| 82 | if (slot & 1) |
| 83 | return 0x02; |
| 84 | else |
| 85 | return 0x03; |
| 86 | } |
| 87 | |
| 88 | |
| 89 | /*! Set a given NCN8025 as described in 'set'. |
| 90 | * \param[in] slot Slot number (0..7) |
| 91 | * \param[in] set Settings that shall be written |
| 92 | * \returns 0 on success; negative on error */ |
| 93 | int ncn8025_set(uint8_t slot, const struct ncn8025_settings *set) |
| 94 | { |
| 95 | const struct i2c_adapter *adap = slot2adapter(slot); |
| 96 | uint8_t reg = slot2data_reg(slot); |
| 97 | uint8_t raw = ncn8025_encode(set); |
| 98 | return i2c_write_reg(adap, SX1503_ADDR, reg, raw); |
| 99 | } |
| 100 | |
| 101 | /*! Get a given NCN8025 state from the chip. |
| 102 | * \param[in] slot Slot number (0..7) |
| 103 | * \param[out] set Settings that are retrieved |
| 104 | * \returns 0 on success; negative on error */ |
| 105 | int ncn8025_get(uint8_t slot, struct ncn8025_settings *set) |
| 106 | { |
| 107 | const struct i2c_adapter *adap = slot2adapter(slot); |
| 108 | uint8_t reg = slot2data_reg(slot); |
| 109 | int rc; |
| 110 | rc = i2c_read_reg(adap, SX1503_ADDR, reg); |
| 111 | if (rc < 0) |
| 112 | return rc; |
| 113 | return ncn8025_decode(rc, set); |
| 114 | } |
| 115 | |
| 116 | /*! default settings we use at start-up: powered off, in reset, slowest clock, 3V */ |
| 117 | static const struct ncn8025_settings def_settings = { |
| 118 | .rstin = true, |
| 119 | .cmdvcc = false, |
| 120 | .led = false, |
| 121 | .clkdiv = SIM_CLKDIV_8, |
| 122 | .vsel = SIM_VOLT_3V0, |
| 123 | }; |
| 124 | |
| 125 | /*! Initialize a given NCN8025/slot. */ |
| 126 | int ncn8025_init(unsigned int slot) |
| 127 | { |
| 128 | const struct i2c_adapter *adap = slot2adapter(slot); |
| 129 | uint8_t reg = slot2dir_reg(slot); |
| 130 | int rc; |
| 131 | /* IO6 of each bank is input (!PRESENT), rest are outputs */ |
| 132 | rc = i2c_write_reg(adap, SX1503_ADDR, reg, 0x40); |
| 133 | if (rc < 0) |
| 134 | return rc; |
| 135 | return ncn8025_set(slot, &def_settings); |
| 136 | } |