1 /* 2 /* 3 /*Copyright (C) 2015 The Android Open Source Project 4 /* 5 /*Licensed under the Apache License, Version 2.0 (the "License"); 6 /*you may not use this file except in compliance with the License. 7 /*You may obtain a copy of the License at 8 /* 9 /* http://www.apache.org/licenses/LICENSE-2.0 10 /* 11 /*Unless required by applicable law or agreed to in writing, software 12 /*distributed under the License is distributed on an "AS IS" BASIS, 13 /*WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 /*See the License for the specific language governing permissions and 15 /*limitations under the License. 16 */ 17 * 18 * This file was copied from https://github.com/devttys0/libmpsse.git (sha1 19 * f1a6744b), and modified to suite the Chromium OS project. 20 * 21 * Internal functions used by libmpsse. 22 * 23 * Craig Heffner 24 * 27 December 2011 25 */ 26 27 #include <string.h> 28 29 #include "trunks/ftdi/support.h" 30 31 /* Write data to the FTDI chip */ 32 int raw_write(struct mpsse_context* mpsse, uint8_t* buf, int size) { 33 int retval = MPSSE_FAIL; 34 35 if (mpsse->mode) { 36 if (ftdi_write_data(&mpsse->ftdi, buf, size) == size) { 37 retval = MPSSE_OK; 38 } 39 } 40 41 return retval; 42 } 43 44 /* Read data from the FTDI chip */ 45 int raw_read(struct mpsse_context* mpsse, uint8_t* buf, int size) { 46 int n = 0, r = 0; 47 48 if (mpsse->mode) { 49 while (n < size) { 50 r = ftdi_read_data(&mpsse->ftdi, buf, size); 51 if (r < 0) 52 break; 53 n += r; 54 } 55 56 if (mpsse->flush_after_read) { 57 /* 58 * Make sure the buffers are cleared after a read or subsequent reads may 59 *fail. 60 * 61 * Is this needed anymore? It slows down repetitive read operations by 62 *~8%. 63 */ 64 ftdi_usb_purge_rx_buffer(&mpsse->ftdi); 65 } 66 } 67 68 return n; 69 } 70 71 /* Sets the read and write timeout periods for bulk usb data transfers. */ 72 void set_timeouts(struct mpsse_context* mpsse, int timeout) { 73 if (mpsse->mode) { 74 mpsse->ftdi.usb_read_timeout = timeout; 75 mpsse->ftdi.usb_write_timeout = timeout; 76 } 77 78 return; 79 } 80 81 /* Convert a frequency to a clock divisor */ 82 uint16_t freq2div(uint32_t system_clock, uint32_t freq) { 83 return (((system_clock / freq) / 2) - 1); 84 } 85 86 /* Convert a clock divisor to a frequency */ 87 uint32_t div2freq(uint32_t system_clock, uint16_t div) { 88 return (system_clock / ((1 + div) * 2)); 89 } 90 91 /* Builds a buffer of commands + data blocks */ 92 uint8_t* build_block_buffer(struct mpsse_context* mpsse, 93 uint8_t cmd, 94 const uint8_t* data, 95 int size, 96 int* buf_size) { 97 uint8_t* buf = NULL; 98 int i = 0, j = 0, k = 0, dsize = 0, num_blocks = 0, total_size = 0, 99 xfer_size = 0; 100 uint16_t rsize = 0; 101 102 *buf_size = 0; 103 104 /* Data block size is 1 in I2C, or when in bitmode */ 105 if (mpsse->mode == I2C || (cmd & MPSSE_BITMODE)) { 106 xfer_size = 1; 107 } else { 108 xfer_size = mpsse->xsize; 109 } 110 111 num_blocks = (size / xfer_size); 112 if (size % xfer_size) { 113 num_blocks++; 114 } 115 116 /* The total size of the data will be the data size + the write command */ 117 total_size = size + (CMD_SIZE * num_blocks); 118 119 /* In I2C we have to add 3 additional commands per data block */ 120 if (mpsse->mode == I2C) { 121 total_size += (CMD_SIZE * 3 * num_blocks); 122 } 123 124 buf = malloc(total_size); 125 if (buf) { 126 memset(buf, 0, total_size); 127 128 for (j = 0; j < num_blocks; j++) { 129 dsize = size - k; 130 if (dsize > xfer_size) { 131 dsize = xfer_size; 132 } 133 134 /* The reported size of this block is block size - 1 */ 135 rsize = dsize - 1; 136 137 /* For I2C we need to ensure that the clock pin is set low prior to 138 * clocking out data */ 139 if (mpsse->mode == I2C) { 140 buf[i++] = SET_BITS_LOW; 141 buf[i++] = mpsse->pstart & ~SK; 142 143 /* On receive, we need to ensure that the data out line is set as an 144 * input to avoid contention on the bus */ 145 if (cmd == mpsse->rx) { 146 buf[i++] = mpsse->tris & ~DO; 147 } else { 148 buf[i++] = mpsse->tris; 149 } 150 } 151 152 /* Copy in the command for this block */ 153 buf[i++] = cmd; 154 buf[i++] = (rsize & 0xFF); 155 if (!(cmd & MPSSE_BITMODE)) { 156 buf[i++] = ((rsize >> 8) & 0xFF); 157 } 158 159 /* On a write, copy the data to transmit after the command */ 160 if (cmd == mpsse->tx || cmd == mpsse->txrx) { 161 memcpy(buf + i, data + k, dsize); 162 163 /* i == offset into buf */ 164 i += dsize; 165 /* k == offset into data */ 166 k += dsize; 167 } 168 169 /* In I2C mode we need to clock one ACK bit after each byte */ 170 if (mpsse->mode == I2C) { 171 /* If we are receiving data, then we need to clock out an ACK for each 172 * byte */ 173 if (cmd == mpsse->rx) { 174 buf[i++] = SET_BITS_LOW; 175 buf[i++] = mpsse->pstart & ~SK; 176 buf[i++] = mpsse->tris; 177 178 buf[i++] = mpsse->tx | MPSSE_BITMODE; 179 buf[i++] = 0; 180 buf[i++] = mpsse->tack; 181 } 182 /* If we are sending data, then we need to clock in an ACK for each byte 183 */ 184 else if (cmd == mpsse->tx) { 185 /* Need to make data out an input to avoid contention on the bus when 186 * the slave sends an ACK */ 187 buf[i++] = SET_BITS_LOW; 188 buf[i++] = mpsse->pstart & ~SK; 189 buf[i++] = mpsse->tris & ~DO; 190 191 buf[i++] = mpsse->rx | MPSSE_BITMODE; 192 buf[i++] = 0; 193 buf[i++] = SEND_IMMEDIATE; 194 } 195 } 196 } 197 198 *buf_size = i; 199 } 200 201 return buf; 202 } 203 204 /* Set the low bit pins high/low */ 205 int set_bits_low(struct mpsse_context* mpsse, int port) { 206 char buf[CMD_SIZE] = {0}; 207 208 buf[0] = SET_BITS_LOW; 209 buf[1] = port; 210 buf[2] = mpsse->tris; 211 212 return raw_write(mpsse, (uint8_t*)&buf, sizeof(buf)); 213 } 214 215 /* Set the high bit pins high/low */ 216 int set_bits_high(struct mpsse_context* mpsse, int port) { 217 char buf[CMD_SIZE] = {0}; 218 219 buf[0] = SET_BITS_HIGH; 220 buf[1] = port; 221 buf[2] = mpsse->trish; 222 223 return raw_write(mpsse, (uint8_t*)&buf, sizeof(buf)); 224 } 225 226 /* Set the GPIO pins high/low */ 227 int gpio_write(struct mpsse_context* mpsse, int pin, int direction) { 228 int retval = MPSSE_FAIL; 229 230 if (mpsse->mode == BITBANG) { 231 if (direction == HIGH) { 232 mpsse->bitbang |= (1 << pin); 233 } else { 234 mpsse->bitbang &= ~(1 << pin); 235 } 236 237 if (set_bits_high(mpsse, mpsse->bitbang) == MPSSE_OK) { 238 retval = raw_write(mpsse, (uint8_t*)&mpsse->bitbang, 1); 239 } 240 } else { 241 /* The first four pins can't be changed unless we are in a stopped status */ 242 if (pin < NUM_GPIOL_PINS && mpsse->status == STOPPED) { 243 /* Convert pin number (0-3) to the corresponding pin bit */ 244 pin = (GPIO0 << pin); 245 246 if (direction == HIGH) { 247 mpsse->pstart |= pin; 248 mpsse->pidle |= pin; 249 mpsse->pstop |= pin; 250 } else { 251 mpsse->pstart &= ~pin; 252 mpsse->pidle &= ~pin; 253 mpsse->pstop &= ~pin; 254 } 255 256 retval = set_bits_low(mpsse, mpsse->pstop); 257 } else if (pin >= NUM_GPIOL_PINS && pin < NUM_GPIO_PINS) { 258 /* Convert pin number (4 - 11) to the corresponding pin bit */ 259 pin -= NUM_GPIOL_PINS; 260 261 if (direction == HIGH) { 262 mpsse->gpioh |= (1 << pin); 263 } else { 264 mpsse->gpioh &= ~(1 << pin); 265 } 266 267 retval = set_bits_high(mpsse, mpsse->gpioh); 268 } 269 } 270 271 return retval; 272 } 273 274 /* Checks if a given MPSSE context is valid. */ 275 int is_valid_context(struct mpsse_context* mpsse) { 276 return mpsse != NULL; 277 } 278