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authorMartin Braun <martin.braun@ettus.com>2014-10-07 09:39:25 +0200
committerMartin Braun <martin.braun@ettus.com>2014-10-07 09:39:25 +0200
commit5bd58bc309e959537e3e820abfa39ee629b140a5 (patch)
tree81e3a611134e02d9118f0aa846b7146234849fe8 /firmware/zpu/lib/i2c_async.c
parent9f6a11173aef5e661100268bd746963d713adb91 (diff)
downloaduhd-5bd58bc309e959537e3e820abfa39ee629b140a5.tar.gz
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Reorganized firmware/ subdirectory (x300->usrp3, zpu->usrp2)
Diffstat (limited to 'firmware/zpu/lib/i2c_async.c')
-rw-r--r--firmware/zpu/lib/i2c_async.c206
1 files changed, 0 insertions, 206 deletions
diff --git a/firmware/zpu/lib/i2c_async.c b/firmware/zpu/lib/i2c_async.c
deleted file mode 100644
index 05c4c3a09..000000000
--- a/firmware/zpu/lib/i2c_async.c
+++ /dev/null
@@ -1,206 +0,0 @@
-//
-// Copyright 2010 Ettus Research LLC
-//
-/*
- * Copyright 2007,2008 Free Software Foundation, Inc.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
- //i2c_async.c: asynchronous (interrupt-driven) routines for I2C.
- //separated out here so we can have a small I2C lib for bootloader and
- //retain interrupt-driven I2C for the main app.
-
-#include "memory_map.h"
-#include "stdint.h"
-#include <string.h>
-#include "pic.h"
-#include "nonstdio.h"
-#include "i2c_async.h"
-
- //asynchronous (interrupt-driven) i2c state variables
-volatile uint8_t i2c_buf[17]; //tx/rx data transfer buffer
-volatile uint8_t *volatile i2c_bufptr = i2c_buf; //ptr to current position
-volatile uint8_t i2c_len = 0; //length remaining in current transfer
-volatile i2c_state_t i2c_state = I2C_STATE_IDLE; //current I2C transfer state
-i2c_dir_t i2c_dir; //I2C transfer direction
-
-void (*volatile i2c_callback)(void); //function pointer to i2c callback to be called when transaction is complete
-static void i2c_irq_handler(unsigned irq);
-inline void i2c_async_err(void);
-
-void i2c_register_handler(void) {
- pic_register_handler(IRQ_I2C, i2c_irq_handler);
-}
-
-
-static void i2c_irq_handler(unsigned irq) {
-//i2c state machine.
-
- //printf("I2C irq handler\n");
- //first let's make sure nothing is f'ed up
- //TODO: uncomment this error checking when we have some way to handle errors
-// if(((i2c_regs->cmd_status & I2C_ST_RXACK) != 0) && i2c_dir == I2C_DIR_WRITE) { //we got a NACK and we didn't send it
-// printf("\tNACK received\n");
-// i2c_async_err();
-// return;
-// }// else printf("\tACK received, proceeding\n");
-
- if(i2c_regs->cmd_status & I2C_ST_AL) {
- printf("\tArbitration lost!\n");
- i2c_async_err();
- return;
- }
-
- if(i2c_regs->cmd_status & I2C_ST_TIP) {
- //printf("\tI2C still busy in interrupt\n");
- return;
- }
-
- //now decide what to do
- switch(i2c_state) {
-
- case I2C_STATE_IDLE:
- //this is an error. in idle state, we shouldn't be transferring data, and the fact that the IRQ fired is terrible bad.
- printf("AAAAAHHHHH INTERRUPT IN THE IDLE STATE AAAHHHHHHHHH\n");
- i2c_async_err();
- break;
-
- case I2C_STATE_CONTROL_BYTE_SENT: //here we've sent the control byte, and we're either clocking data in or out now, but we haven't received a byte yet.
- case I2C_STATE_DATA: //here we're sending/receiving data and if we're receiving there's data in the data reg
-
- //if(i2c_state == I2C_STATE_DATA) printf("\tI2C in state DATA with dir=%d and len=%d\n", i2c_dir, i2c_len);
- //else printf("\tI2C in state CONTROL_BYTE_SENT with dir=%d and len=%d\n", i2c_dir, i2c_len);
-
- if(i2c_dir == I2C_DIR_READ) {
- if(i2c_state == I2C_STATE_DATA) *(i2c_bufptr++) = i2c_regs->data;
- //printf("\tRead %x\n", *(i2c_bufptr-1));
- //set up another data byte
- if(i2c_len > 1) //only one more byte to transfer
- i2c_regs->cmd_status = I2C_CMD_RD;
- else
- i2c_regs->cmd_status = I2C_CMD_RD | I2C_CMD_NACK | I2C_CMD_STOP;
- }
- else if(i2c_dir == I2C_DIR_WRITE) {
- //write a byte
- //printf("\tWriting %x\n", *i2c_bufptr);
- i2c_regs->data = *(i2c_bufptr++);
- if(i2c_len > 1)
- i2c_regs->cmd_status = I2C_CMD_WR;
- else {
- //printf("\tGenerating STOP\n");
- i2c_regs->cmd_status = I2C_CMD_WR | I2C_CMD_STOP;
- }
- };
- i2c_len--;
- if(i2c_len == 0) i2c_state = I2C_STATE_LAST_BYTE;
- else i2c_state = I2C_STATE_DATA; //takes care of the addr_sent->data transition
- break;
-
-
- case I2C_STATE_LAST_BYTE: //here we've already sent the last read request and the last data is waiting for us.
- //printf("\tI2C in state LAST BYTE\n");
-
- if(i2c_dir == I2C_DIR_READ) {
- *(i2c_bufptr++) = i2c_regs->data;
- //printf("\tRead %x\n", *(i2c_bufptr-1));
- i2c_state = I2C_STATE_DATA_READY;
- } else {
- i2c_state = I2C_STATE_IDLE;
- }
- i2c_regs->ctrl &= ~I2C_CTRL_IE; //disable interrupts until next time
-
- if(i2c_callback) {
- i2c_callback(); //if we registered a callback, call it!
- }
-
- break;
-
-
- default: //terrible things have happened.
- break;
- }
-
-}
-
-void i2c_register_callback(void (*volatile callback)(void)) {
- i2c_callback = callback;
-}
-
-inline void i2c_async_err(void) {
- i2c_state = I2C_STATE_IDLE;
- i2c_regs->ctrl &= ~I2C_CTRL_IE;
- printf("I2C error\n");
-//TODO: set an error flag instead of just dropping things on the floor
- i2c_regs->cmd_status = I2C_CMD_STOP;
-}
-
-bool i2c_async_read(uint8_t addr, unsigned int len) {
- //printf("Starting async read\n");
- if(i2c_state != I2C_STATE_IDLE) return false; //sorry mario but your i2c is in another castle
- if(len == 0) return true; //just idiot-proofing
- if(len > sizeof(i2c_buf)) return false;
-
- //disable I2C interrupts and clear pending interrupts on the I2C device
- i2c_regs->ctrl &= ~I2C_CTRL_IE;
- i2c_regs->cmd_status |= I2C_CMD_IACK;
-
- i2c_len = len;
- i2c_dir = I2C_DIR_READ;
- i2c_bufptr = i2c_buf;
- //then set up the transfer by issuing the control byte
- i2c_regs->ctrl |= I2C_CTRL_IE;
- i2c_regs->data = (addr << 1) | 0x01; //7 bit addr and read bit
- i2c_regs->cmd_status = I2C_CMD_WR | I2C_CMD_START; //generate start & start writing addr
- //update the state so the irq handler knows what's going on
- i2c_state = I2C_STATE_CONTROL_BYTE_SENT;
- return true;
-}
-
-bool i2c_async_write(uint8_t addr, const uint8_t *buf, unsigned int len) {
- //printf("Starting async write\n");
- if(i2c_state != I2C_STATE_IDLE) return false; //sorry mario but your i2c is in another castle
- if(len > sizeof(i2c_buf)) return false;
-
- //disable I2C interrupts and clear pending interrupts on the I2C device
- i2c_regs->ctrl &= ~I2C_CTRL_IE;
- i2c_regs->cmd_status |= I2C_CMD_IACK;
-
- //copy the buffer into our own if writing
- memcpy((void *)i2c_buf, buf, len);
-
- i2c_len = len;
- i2c_dir = I2C_DIR_WRITE;
- i2c_bufptr = i2c_buf;
- //then set up the transfer by issuing the control byte
- i2c_regs->ctrl |= I2C_CTRL_IE;
- i2c_regs->data = (addr << 1) | 0x00; //7 bit addr and read bit
- i2c_regs->cmd_status = I2C_CMD_WR | I2C_CMD_START; //generate start & start writing addr
- //update the state so the irq handler knows what's going on
- i2c_state = I2C_STATE_CONTROL_BYTE_SENT;
-
- return true;
-}
-
-//TODO: determine if it's better to read sequentially into the user's buffer, copy on transfer complete, or copy on request (shown below). probably best to copy on request.
-bool i2c_async_data_ready(void *buf) {
- if(i2c_state == I2C_STATE_DATA_READY) {
- i2c_state = I2C_STATE_IDLE;
- memcpy(buf, (void *)i2c_buf, (i2c_bufptr - i2c_buf)); //TODO: not really comfortable with this
- //printf("Copying %d bytes to user buffer\n", i2c_bufptr-i2c_buf);
- return true;
- }
- return false;
-}
-