/*
/*
/*Copyright (C) 2015 The Android Open Source Project
/*
/*Licensed under the Apache License, Version 2.0 (the "License");
/*you may not use this file except in compliance with the License.
/*You may obtain a copy of the License at
/*
/* http://www.apache.org/licenses/LICENSE-2.0
/*
/*Unless required by applicable law or agreed to in writing, software
/*distributed under the License is distributed on an "AS IS" BASIS,
/*WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/*See the License for the specific language governing permissions and
/*limitations under the License.
*/
*
* This file was copied from https://github.com/devttys0/libmpsse.git (sha1
* f1a6744b), and modified to suite the Chromium OS project.
*
* Internal functions used by libmpsse.
*
* Craig Heffner
* 27 December 2011
*/
#include <string.h>
#include "trunks/ftdi/support.h"
/* Write data to the FTDI chip */
int raw_write(struct mpsse_context* mpsse, uint8_t* buf, int size) {
int retval = MPSSE_FAIL;
if (mpsse->mode) {
if (ftdi_write_data(&mpsse->ftdi, buf, size) == size) {
retval = MPSSE_OK;
}
}
return retval;
}
/* Read data from the FTDI chip */
int raw_read(struct mpsse_context* mpsse, uint8_t* buf, int size) {
int n = 0, r = 0;
if (mpsse->mode) {
while (n < size) {
r = ftdi_read_data(&mpsse->ftdi, buf, size);
if (r < 0)
break;
n += r;
}
if (mpsse->flush_after_read) {
/*
* Make sure the buffers are cleared after a read or subsequent reads may
*fail.
*
* Is this needed anymore? It slows down repetitive read operations by
*~8%.
*/
ftdi_usb_purge_rx_buffer(&mpsse->ftdi);
}
}
return n;
}
/* Sets the read and write timeout periods for bulk usb data transfers. */
void set_timeouts(struct mpsse_context* mpsse, int timeout) {
if (mpsse->mode) {
mpsse->ftdi.usb_read_timeout = timeout;
mpsse->ftdi.usb_write_timeout = timeout;
}
return;
}
/* Convert a frequency to a clock divisor */
uint16_t freq2div(uint32_t system_clock, uint32_t freq) {
return (((system_clock / freq) / 2) - 1);
}
/* Convert a clock divisor to a frequency */
uint32_t div2freq(uint32_t system_clock, uint16_t div) {
return (system_clock / ((1 + div) * 2));
}
/* Builds a buffer of commands + data blocks */
uint8_t* build_block_buffer(struct mpsse_context* mpsse,
uint8_t cmd,
const uint8_t* data,
int size,
int* buf_size) {
uint8_t* buf = NULL;
int i = 0, j = 0, k = 0, dsize = 0, num_blocks = 0, total_size = 0,
xfer_size = 0;
uint16_t rsize = 0;
*buf_size = 0;
/* Data block size is 1 in I2C, or when in bitmode */
if (mpsse->mode == I2C || (cmd & MPSSE_BITMODE)) {
xfer_size = 1;
} else {
xfer_size = mpsse->xsize;
}
num_blocks = (size / xfer_size);
if (size % xfer_size) {
num_blocks++;
}
/* The total size of the data will be the data size + the write command */
total_size = size + (CMD_SIZE * num_blocks);
/* In I2C we have to add 3 additional commands per data block */
if (mpsse->mode == I2C) {
total_size += (CMD_SIZE * 3 * num_blocks);
}
buf = malloc(total_size);
if (buf) {
memset(buf, 0, total_size);
for (j = 0; j < num_blocks; j++) {
dsize = size - k;
if (dsize > xfer_size) {
dsize = xfer_size;
}
/* The reported size of this block is block size - 1 */
rsize = dsize - 1;
/* For I2C we need to ensure that the clock pin is set low prior to
* clocking out data */
if (mpsse->mode == I2C) {
buf[i++] = SET_BITS_LOW;
buf[i++] = mpsse->pstart & ~SK;
/* On receive, we need to ensure that the data out line is set as an
* input to avoid contention on the bus */
if (cmd == mpsse->rx) {
buf[i++] = mpsse->tris & ~DO;
} else {
buf[i++] = mpsse->tris;
}
}
/* Copy in the command for this block */
buf[i++] = cmd;
buf[i++] = (rsize & 0xFF);
if (!(cmd & MPSSE_BITMODE)) {
buf[i++] = ((rsize >> 8) & 0xFF);
}
/* On a write, copy the data to transmit after the command */
if (cmd == mpsse->tx || cmd == mpsse->txrx) {
memcpy(buf + i, data + k, dsize);
/* i == offset into buf */
i += dsize;
/* k == offset into data */
k += dsize;
}
/* In I2C mode we need to clock one ACK bit after each byte */
if (mpsse->mode == I2C) {
/* If we are receiving data, then we need to clock out an ACK for each
* byte */
if (cmd == mpsse->rx) {
buf[i++] = SET_BITS_LOW;
buf[i++] = mpsse->pstart & ~SK;
buf[i++] = mpsse->tris;
buf[i++] = mpsse->tx | MPSSE_BITMODE;
buf[i++] = 0;
buf[i++] = mpsse->tack;
}
/* If we are sending data, then we need to clock in an ACK for each byte
*/
else if (cmd == mpsse->tx) {
/* Need to make data out an input to avoid contention on the bus when
* the slave sends an ACK */
buf[i++] = SET_BITS_LOW;
buf[i++] = mpsse->pstart & ~SK;
buf[i++] = mpsse->tris & ~DO;
buf[i++] = mpsse->rx | MPSSE_BITMODE;
buf[i++] = 0;
buf[i++] = SEND_IMMEDIATE;
}
}
}
*buf_size = i;
}
return buf;
}
/* Set the low bit pins high/low */
int set_bits_low(struct mpsse_context* mpsse, int port) {
char buf[CMD_SIZE] = {0};
buf[0] = SET_BITS_LOW;
buf[1] = port;
buf[2] = mpsse->tris;
return raw_write(mpsse, (uint8_t*)&buf, sizeof(buf));
}
/* Set the high bit pins high/low */
int set_bits_high(struct mpsse_context* mpsse, int port) {
char buf[CMD_SIZE] = {0};
buf[0] = SET_BITS_HIGH;
buf[1] = port;
buf[2] = mpsse->trish;
return raw_write(mpsse, (uint8_t*)&buf, sizeof(buf));
}
/* Set the GPIO pins high/low */
int gpio_write(struct mpsse_context* mpsse, int pin, int direction) {
int retval = MPSSE_FAIL;
if (mpsse->mode == BITBANG) {
if (direction == HIGH) {
mpsse->bitbang |= (1 << pin);
} else {
mpsse->bitbang &= ~(1 << pin);
}
if (set_bits_high(mpsse, mpsse->bitbang) == MPSSE_OK) {
retval = raw_write(mpsse, (uint8_t*)&mpsse->bitbang, 1);
}
} else {
/* The first four pins can't be changed unless we are in a stopped status */
if (pin < NUM_GPIOL_PINS && mpsse->status == STOPPED) {
/* Convert pin number (0-3) to the corresponding pin bit */
pin = (GPIO0 << pin);
if (direction == HIGH) {
mpsse->pstart |= pin;
mpsse->pidle |= pin;
mpsse->pstop |= pin;
} else {
mpsse->pstart &= ~pin;
mpsse->pidle &= ~pin;
mpsse->pstop &= ~pin;
}
retval = set_bits_low(mpsse, mpsse->pstop);
} else if (pin >= NUM_GPIOL_PINS && pin < NUM_GPIO_PINS) {
/* Convert pin number (4 - 11) to the corresponding pin bit */
pin -= NUM_GPIOL_PINS;
if (direction == HIGH) {
mpsse->gpioh |= (1 << pin);
} else {
mpsse->gpioh &= ~(1 << pin);
}
retval = set_bits_high(mpsse, mpsse->gpioh);
}
}
return retval;
}
/* Checks if a given MPSSE context is valid. */
int is_valid_context(struct mpsse_context* mpsse) {
return mpsse != NULL;
}