~ruther/qmk_firmware

e7a5c006d9777a4009da934f408961aa2d2e6fb1 — Joel Challis 4 years ago 2d66352
Refactor use of legacy i2c implementation (#14341)

6 files changed, 25 insertions(+), 421 deletions(-)

D keyboards/sx60/i2cmaster.h
M keyboards/sx60/matrix.c
M keyboards/sx60/rules.mk
M keyboards/sx60/sx60.c
M keyboards/sx60/sx60.h
D keyboards/sx60/twimaster.c
D keyboards/sx60/i2cmaster.h => keyboards/sx60/i2cmaster.h +0 -178
@@ 1,178 0,0 @@
#ifndef _I2CMASTER_H
#define _I2CMASTER_H   1
/************************************************************************* 
* Title:    C include file for the I2C master interface 
*           (i2cmaster.S or twimaster.c)
* Author:   Peter Fleury <pfleury@gmx.ch>  http://jump.to/fleury
* File:     $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
* Target:   any AVR device
* Usage:    see Doxygen manual
**************************************************************************/

#ifdef DOXYGEN
/**
 @defgroup pfleury_ic2master I2C Master library
 @code #include <i2cmaster.h> @endcode
  
 @brief I2C (TWI) Master Software Library

 Basic routines for communicating with I2C slave devices. This single master 
 implementation is limited to one bus master on the I2C bus. 

 This I2c library is implemented as a compact assembler software implementation of the I2C protocol 
 which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
 Since the API for these two implementations is exactly the same, an application can be linked either against the
 software I2C implementation or the hardware I2C implementation.

 Use 4.7k pull-up resistor on the SDA and SCL pin.
 
 Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module 
 i2cmaster.S to your target when using the software I2C implementation ! 
 
 Adjust the  CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.

 @note 
    The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted 
    to GNU assembler and AVR-GCC C call interface.
    Replaced the incorrect quarter period delays found in AVR300 with 
    half period delays. 
    
 @author Peter Fleury pfleury@gmx.ch  http://jump.to/fleury

 @par API Usage Example
  The following code shows typical usage of this library, see example test_i2cmaster.c

 @code

 #include <i2cmaster.h>


 #define Dev24C02  0xA2      // device address of EEPROM 24C02, see datasheet

 int main(void)
 {
     unsigned char ret;

     i2c_init();                             // initialize I2C library

     // write 0x75 to EEPROM address 5 (Byte Write) 
     i2c_start_wait(Dev24C02+I2C_WRITE);     // set device address and write mode
     i2c_write(0x05);                        // write address = 5
     i2c_write(0x75);                        // write value 0x75 to EEPROM
     i2c_stop();                             // set stop conditon = release bus


     // read previously written value back from EEPROM address 5 
     i2c_start_wait(Dev24C02+I2C_WRITE);     // set device address and write mode

     i2c_write(0x05);                        // write address = 5
     i2c_rep_start(Dev24C02+I2C_READ);       // set device address and read mode

     ret = i2c_readNak();                    // read one byte from EEPROM
     i2c_stop();

     for(;;);
 }
 @endcode

*/
#endif /* DOXYGEN */

/**@{*/

#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
#endif

#include <avr/io.h>

/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
#define I2C_READ    1

/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
#define I2C_WRITE   0


/**
 @brief initialize the I2C master interace. Need to be called only once 
 @param  void
 @return none
 */
extern void i2c_init(void);


/** 
 @brief Terminates the data transfer and releases the I2C bus 
 @param void
 @return none
 */
extern void i2c_stop(void);


/** 
 @brief Issues a start condition and sends address and transfer direction 
  
 @param    addr address and transfer direction of I2C device
 @retval   0   device accessible 
 @retval   1   failed to access device 
 */
extern unsigned char i2c_start(unsigned char addr);


/**
 @brief Issues a repeated start condition and sends address and transfer direction 

 @param   addr address and transfer direction of I2C device
 @retval  0 device accessible
 @retval  1 failed to access device
 */
extern unsigned char i2c_rep_start(unsigned char addr);


/**
 @brief Issues a start condition and sends address and transfer direction 
   
 If device is busy, use ack polling to wait until device ready 
 @param    addr address and transfer direction of I2C device
 @return   none
 */
extern void i2c_start_wait(unsigned char addr);

 
/**
 @brief Send one byte to I2C device
 @param    data  byte to be transfered
 @retval   0 write successful
 @retval   1 write failed
 */
extern unsigned char i2c_write(unsigned char data);


/**
 @brief    read one byte from the I2C device, request more data from device 
 @return   byte read from I2C device
 */
extern unsigned char i2c_readAck(void);

/**
 @brief    read one byte from the I2C device, read is followed by a stop condition 
 @return   byte read from I2C device
 */
extern unsigned char i2c_readNak(void);

/** 
 @brief    read one byte from the I2C device
 
 Implemented as a macro, which calls either i2c_readAck or i2c_readNak
 
 @param    ack 1 send ack, request more data from device<br>
               0 send nak, read is followed by a stop condition 
 @return   byte read from I2C device
 */
extern unsigned char i2c_read(unsigned char ack);
#define i2c_read(ack)  (ack) ? i2c_readAck() : i2c_readNak(); 


/**@}*/
#endif

M keyboards/sx60/matrix.c => keyboards/sx60/matrix.c +7 -14
@@ 243,15 243,11 @@ static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
        /* if there was an error */
        return 0;
    } else {
        uint16_t data = 0;
        mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
        mcp23018_status = i2c_write(GPIOA);             if (mcp23018_status) goto out;
        mcp23018_status = i2c_start(I2C_ADDR_READ);     if (mcp23018_status) goto out;
        data = i2c_readNak();
        data = ~data;
    out:
        i2c_stop();
        current_matrix[current_row] |= (data << 8);
        uint8_t data = 0;
        mcp23018_status = i2c_readReg(I2C_ADDR, GPIOA, &data, 1, I2C_TIMEOUT);
        if (!mcp23018_status) {
            current_matrix[current_row] |= (~((uint16_t)data) << 8);
        }
    }

    /* For each col... */


@@ 278,11 274,8 @@ static void select_row(uint8_t row)
        /* set active row low  : 0
           set active row output : 1
           set other rows hi-Z : 1 */
        mcp23018_status = i2c_start(I2C_ADDR_WRITE);   if (mcp23018_status) goto out;
        mcp23018_status = i2c_write(GPIOB);            if (mcp23018_status) goto out;
        mcp23018_status = i2c_write(0xFF & ~(1<<abs(row-4))); if (mcp23018_status) goto out;
    out:
        i2c_stop();
        uint8_t port = 0xFF & ~(1<<abs(row-4));
        mcp23018_status = i2c_writeReg(I2C_ADDR, GPIOB, &port, 1, I2C_TIMEOUT);
    }

    uint8_t pin = row_pins[row];

M keyboards/sx60/rules.mk => keyboards/sx60/rules.mk +2 -2
@@ 27,5 27,5 @@ RGBLIGHT_ENABLE = no
CUSTOM_MATRIX = yes

# project specific files
SRC =  twimaster.c \
  matrix.c
QUANTUM_LIB_SRC += i2c_master.c
SRC += matrix.c

M keyboards/sx60/sx60.c => keyboards/sx60/sx60.c +14 -17
@@ 1,5 1,5 @@
#include "sx60.h"
#include "i2cmaster.h"
#include "i2c_master.h"


bool i2c_initialized = 0;


@@ 18,21 18,18 @@ uint8_t init_mcp23018(void) {

    /* B Pins are Row, A pins are Columns 
       Set them to output */
    mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
    mcp23018_status = i2c_write(IODIRA);            if (mcp23018_status) goto out;
    mcp23018_status = i2c_write(0b11111111);        if (mcp23018_status) goto out;
    /* Now write to IODIRB */
    mcp23018_status = i2c_write(0b00000000);        if (mcp23018_status) goto out;
    i2c_stop();

    mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
    mcp23018_status = i2c_write(GPPUA);             if (mcp23018_status) goto out;
    mcp23018_status = i2c_write(0b11111111);        if (mcp23018_status) goto out;
    /* Now write to GPPUB */
    mcp23018_status = i2c_write(0b00000000);        if (mcp23018_status) goto out;

out:
    i2c_stop();

    static uint8_t direction[2] = {
        0b11111111,
        0b00000000,
    };
    static uint8_t pullup[2] = {
        0b11111111,
        0b00000000,
    };

    mcp23018_status = i2c_writeReg(I2C_ADDR, IODIRA, direction, 2, I2C_TIMEOUT);
    if (mcp23018_status) return mcp23018_status;

    mcp23018_status = i2c_writeReg(I2C_ADDR, GPPUA, pullup, 2, I2C_TIMEOUT);
    return mcp23018_status;
}

M keyboards/sx60/sx60.h => keyboards/sx60/sx60.h +2 -3
@@ 4,13 4,12 @@
#include "quantum.h"
#include <stdint.h>
#include <stdbool.h>
#include "i2cmaster.h"
#include "i2c_master.h"
#include <util/delay.h>

/* I2C aliases and register addresses (see "mcp23018.md") */
#define I2C_ADDR        0b0100000
#define I2C_ADDR_WRITE  ( (I2C_ADDR<<1) | I2C_WRITE )
#define I2C_ADDR_READ   ( (I2C_ADDR<<1) | I2C_READ  )
#define I2C_TIMEOUT     100
#define IODIRA          0x00            /* i/o direction register */
#define IODIRB          0x01
#define GPPUA           0x0C            /* GPIO pull-up resistor register */

D keyboards/sx60/twimaster.c => keyboards/sx60/twimaster.c +0 -207
@@ 1,207 0,0 @@
/*************************************************************************
* Title:    I2C master library using hardware TWI interface
* Author:   Peter Fleury <pfleury@gmx.ch>  http://jump.to/fleury
* File:     $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $
* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
* Target:   any AVR device with hardware TWI
* Usage:    API compatible with I2C Software Library i2cmaster.h
**************************************************************************/
#include <inttypes.h>
#include <compat/twi.h>

#include <i2cmaster.h>

/* define CPU frequency in Hz here if not defined in Makefile */
#ifndef F_CPU
#define F_CPU 16000000UL
#endif

/* I2C clock in Hz */
#define SCL_CLOCK  400000L


/*************************************************************************
 Initialization of the I2C bus interface. Need to be called only once
*************************************************************************/
void i2c_init(void)
{
  /* initialize TWI clock
   * minimal values in Bit Rate Register (TWBR) and minimal Prescaler
   * bits in the TWI Status Register should give us maximal possible
   * I2C bus speed - about 444 kHz
   *
   * for more details, see 20.5.2 in ATmega16/32 secification
   */

  TWSR = 0;     /* no prescaler */
  TWBR = 10;    /* must be >= 10 for stable operation */

}/* i2c_init */


/*************************************************************************
  Issues a start condition and sends address and transfer direction.
  return 0 = device accessible, 1= failed to access device
*************************************************************************/
unsigned char i2c_start(unsigned char address)
{
    uint8_t   twst;

  /* send START condition */
  TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
 
  /* wait until transmission completed */
  while(!(TWCR & (1<<TWINT)));

  /* check value of TWI Status Register. Mask prescaler bits. */
  twst = TW_STATUS & 0xF8;
  if ( (twst != TW_START) && (twst != TW_REP_START)) return 1;

  /* send device address */
  TWDR = address;
  TWCR = (1<<TWINT) | (1<<TWEN);

  /* wail until transmission completed and ACK/NACK has been received */
  while(!(TWCR & (1<<TWINT)));

  /* check value of TWI Status Register. Mask prescaler bits. */
  twst = TW_STATUS & 0xF8;
  if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;

  return 0;

}/* i2c_start */


/*************************************************************************
 Issues a start condition and sends address and transfer direction.
 If device is busy, use ack polling to wait until device is ready

 Input:   address and transfer direction of I2C device
*************************************************************************/
void i2c_start_wait(unsigned char address)
{
    uint8_t   twst;


    while ( 1 )
    {
      /* send START condition */
      TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);

      /* wait until transmission completed */
      while(!(TWCR & (1<<TWINT)));

      /* check value of TWI Status Register. Mask prescaler bits. */
      twst = TW_STATUS & 0xF8;
      if ( (twst != TW_START) && (twst != TW_REP_START)) continue;

      /* send device address */
      TWDR = address;
      TWCR = (1<<TWINT) | (1<<TWEN);

      /* wail until transmission completed */
      while(!(TWCR & (1<<TWINT)));

      /* check value of TWI Status Register. Mask prescaler bits. */
      twst = TW_STATUS & 0xF8;
      if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
      {
          /* device busy, send stop condition to terminate write operation */
          TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);

          /* wait until stop condition is executed and bus released */
          while(TWCR & (1<<TWSTO));

          continue;
      }
      
      break;
     }

}/* i2c_start_wait */


/*************************************************************************
 Issues a repeated start condition and sends address and transfer direction

 Input:   address and transfer direction of I2C device

 Return:  0 device accessible
          1 failed to access device
*************************************************************************/
unsigned char i2c_rep_start(unsigned char address)
{
    return i2c_start( address );

}/* i2c_rep_start */


/*************************************************************************
 Terminates the data transfer and releases the I2C bus
*************************************************************************/
void i2c_stop(void)
{
  /* send stop condition */
  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);

  /* wait until stop condition is executed and bus released */
  while(TWCR & (1<<TWSTO));

}/* i2c_stop */


/*************************************************************************
  Send one byte to I2C device

  Input:    byte to be transfered
  Return:   0 write successful
            1 write failed
*************************************************************************/
unsigned char i2c_write( unsigned char data )
{
    uint8_t   twst;

  /* send data to the previously addressed device */
  TWDR = data;
  TWCR = (1<<TWINT) | (1<<TWEN);

  /* wait until transmission completed */
  while(!(TWCR & (1<<TWINT)));

  /* check value of TWI Status Register. Mask prescaler bits */
  twst = TW_STATUS & 0xF8;
  if( twst != TW_MT_DATA_ACK) return 1;
  return 0;

}/* i2c_write */


/*************************************************************************
 Read one byte from the I2C device, request more data from device

 Return:  byte read from I2C device
*************************************************************************/
unsigned char i2c_readAck(void)
{
  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
  while(!(TWCR & (1<<TWINT)));

  return TWDR;

}/* i2c_readAck */


/*************************************************************************
 Read one byte from the I2C device, read is followed by a stop condition

 Return:  byte read from I2C device
*************************************************************************/
unsigned char i2c_readNak(void)
{
  TWCR = (1<<TWINT) | (1<<TWEN);
  while(!(TWCR & (1<<TWINT)));

  return TWDR;

}/* i2c_readNak */