From 682555faac8a67deff5688b956165cd1c39389cb Mon Sep 17 00:00:00 2001
From: Jack Humbert <jack.humb@gmail.com>
Date: Tue, 15 May 2018 22:30:58 -0400
Subject: [PATCH] i2c fix

---
 drivers/avr/i2c_master.c          | 42 +++++++++++++++++--------------
 drivers/avr/is31fl3731.c          |  7 ++++--
 keyboards/ergodox_ez/ergodox_ez.c |  4 +--
 keyboards/ergodox_ez/ergodox_ez.h |  2 +-
 keyboards/ergodox_ez/matrix.c     |  3 +--
 keyboards/ergodox_ez/rules.mk     |  4 +--
 6 files changed, 33 insertions(+), 29 deletions(-)

diff --git a/drivers/avr/i2c_master.c b/drivers/avr/i2c_master.c
index f4a4bb7b0b..bcf92153c5 100755
--- a/drivers/avr/i2c_master.c
+++ b/drivers/avr/i2c_master.c
@@ -13,32 +13,34 @@
 
 void i2c_init(void)
 {
+  TWSR = 0;     /* no prescaler */
 	TWBR = (uint8_t)TWBR_val;
+  //TWBR = 10;
 }
 
 uint8_t i2c_start(uint8_t address)
 {
 	// reset TWI control register
-	TWCR = 0;
-	// transmit START condition 
+	//TWCR = 0;
+	// transmit START condition
 	TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
 	// wait for end of transmission
 	while( !(TWCR & (1<<TWINT)) );
-	
+
 	// check if the start condition was successfully transmitted
-	if((TWSR & 0xF8) != TW_START){ return 1; }
-	
+	if(((TW_STATUS & 0xF8) != TW_START) && ((TW_STATUS & 0xF8) != TW_REP_START)){ return 1; }
+
 	// load slave address into data register
 	TWDR = address;
 	// start transmission of address
 	TWCR = (1<<TWINT) | (1<<TWEN);
 	// wait for end of transmission
 	while( !(TWCR & (1<<TWINT)) );
-	
+
 	// check if the device has acknowledged the READ / WRITE mode
 	uint8_t twst = TW_STATUS & 0xF8;
 	if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
-	
+
 	return 0;
 }
 
@@ -50,17 +52,17 @@ uint8_t i2c_write(uint8_t data)
 	TWCR = (1<<TWINT) | (1<<TWEN);
 	// wait for end of transmission
 	while( !(TWCR & (1<<TWINT)) );
-	
-	if( (TWSR & 0xF8) != TW_MT_DATA_ACK ){ return 1; }
-	
+
+	if( (TW_STATUS & 0xF8) != TW_MT_DATA_ACK ){ return 1; }
+
 	return 0;
 }
 
 uint8_t i2c_read_ack(void)
 {
-	
+
 	// start TWI module and acknowledge data after reception
-	TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA); 
+	TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
 	// wait for end of transmission
 	while( !(TWCR & (1<<TWINT)) );
 	// return received data from TWDR
@@ -69,7 +71,7 @@ uint8_t i2c_read_ack(void)
 
 uint8_t i2c_read_nack(void)
 {
-	
+
 	// start receiving without acknowledging reception
 	TWCR = (1<<TWINT) | (1<<TWEN);
 	// wait for end of transmission
@@ -81,29 +83,29 @@ uint8_t i2c_read_nack(void)
 uint8_t i2c_transmit(uint8_t address, uint8_t* data, uint16_t length)
 {
 	if (i2c_start(address | I2C_WRITE)) return 1;
-	
+
 	for (uint16_t i = 0; i < length; i++)
 	{
 		if (i2c_write(data[i])) return 1;
 	}
-	
+
 	i2c_stop();
-	
+
 	return 0;
 }
 
 uint8_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length)
 {
 	if (i2c_start(address | I2C_READ)) return 1;
-	
+
 	for (uint16_t i = 0; i < (length-1); i++)
 	{
 		data[i] = i2c_read_ack();
 	}
 	data[(length-1)] = i2c_read_nack();
-	
+
 	i2c_stop();
-	
+
 	return 0;
 }
 
@@ -146,4 +148,6 @@ void i2c_stop(void)
 {
 	// transmit STOP condition
 	TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+  // wait until stop condition is executed and bus released
+  while(TWCR & (1<<TWSTO));
 }
diff --git a/drivers/avr/is31fl3731.c b/drivers/avr/is31fl3731.c
index c7a99e3a3d..13dfe6eaf6 100644
--- a/drivers/avr/is31fl3731.c
+++ b/drivers/avr/is31fl3731.c
@@ -84,7 +84,8 @@ void IS31FL3731_write_register( uint8_t addr, uint8_t reg, uint8_t data )
 	g_twi_transfer_buffer[1] = data;
 
 	//Transmit data until succesful
-	while(i2c_transmit(addr << 1, g_twi_transfer_buffer,2) != 0); 
+  //while(i2c_transmit(addr << 1, g_twi_transfer_buffer,2) != 0);
+  i2c_transmit(addr << 1, g_twi_transfer_buffer,2);
 }
 
 void IS31FL3731_write_pwm_buffer( uint8_t addr, uint8_t *pwm_buffer )
@@ -108,7 +109,9 @@ void IS31FL3731_write_pwm_buffer( uint8_t addr, uint8_t *pwm_buffer )
 		}
 
 		//Transmit buffer until succesful
-		while(i2c_transmit(addr << 1, g_twi_transfer_buffer,17) != 0);
+		//while(i2c_transmit(addr << 1, g_twi_transfer_buffer,17) != 0);
+    i2c_transmit(addr << 1, g_twi_transfer_buffer,17);
+
 	}
 }
 
diff --git a/keyboards/ergodox_ez/ergodox_ez.c b/keyboards/ergodox_ez/ergodox_ez.c
index 21854ef77e..36eb58a3c7 100644
--- a/keyboards/ergodox_ez/ergodox_ez.c
+++ b/keyboards/ergodox_ez/ergodox_ez.c
@@ -1,6 +1,4 @@
 #include QMK_KEYBOARD_H
-#include "i2cmaster.h"
-
 
 extern inline void ergodox_board_led_on(void);
 extern inline void ergodox_right_led_1_on(void);
@@ -329,7 +327,7 @@ const rgb_led g_rgb_leds[DRIVER_LED_TOTAL] = {
     {{3|(9<<4)},   {24.9*0, 16*2}, 0}, // LED 20
 
     {{4|(6<<4)},   {24.9*3, 16*2}, 0}, // LED 21
-    {{4|(7<<4)},   {24.9*3, 16*2}, 0}, // LED 22
+    {{4|(7<<4)},   {24.9*2, 16*2}, 0}, // LED 22
     {{4|(8<<4)},   {24.9*1, 16*2}, 0}, // LED 23
     {{4|(9<<4)},   {24.9*0, 16*2}, 0}, // LED 24
 };
diff --git a/keyboards/ergodox_ez/ergodox_ez.h b/keyboards/ergodox_ez/ergodox_ez.h
index eda6d767cf..3ffc32553c 100644
--- a/keyboards/ergodox_ez/ergodox_ez.h
+++ b/keyboards/ergodox_ez/ergodox_ez.h
@@ -4,7 +4,7 @@
 #include "quantum.h"
 #include <stdint.h>
 #include <stdbool.h>
-#include "i2cmaster.h"
+#include "i2c_master.h"
 #include <util/delay.h>
 
 #define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
diff --git a/keyboards/ergodox_ez/matrix.c b/keyboards/ergodox_ez/matrix.c
index e101711334..2aad997817 100644
--- a/keyboards/ergodox_ez/matrix.c
+++ b/keyboards/ergodox_ez/matrix.c
@@ -34,7 +34,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "util.h"
 #include "matrix.h"
 #include QMK_KEYBOARD_H
-#include "i2cmaster.h"
 #ifdef DEBUG_MATRIX_SCAN_RATE
 #include  "timer.h"
 #endif
@@ -297,7 +296,7 @@ static matrix_row_t read_cols(uint8_t row)
             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_start(I2C_ADDR_READ);     if (mcp23018_status) goto out;
-            data = i2c_readNak();
+            data = i2c_read_nack();
             data = ~data;
         out:
             i2c_stop();
diff --git a/keyboards/ergodox_ez/rules.mk b/keyboards/ergodox_ez/rules.mk
index a3b2ba5cab..0e0b3cdefd 100644
--- a/keyboards/ergodox_ez/rules.mk
+++ b/keyboards/ergodox_ez/rules.mk
@@ -15,8 +15,8 @@
 #----------------------------------------------------------------------------
 
 # # project specific files
-SRC = twimaster.c \
-	  matrix.c
+SRC = matrix.c \
+  i2c_master.c
 
 # MCU name
 MCU = atmega32u4