Add DM320 I²C driver, although not (yet) enabled in the sources.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17050 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 116 insertions, 42 deletions

diff --git a/firmware/target/arm/tms320dm320/i2c-dm320.c b/firmware/target/arm/tms320dm320/i2c-dm320.c
index 4ca5eb7118..cb6411e412 100755
--- a/firmware/target/arm/tms320dm320/i2c-dm320.c
+++ b/firmware/target/arm/tms320dm320/i2c-dm320.c
@@ -7,7 +7,9 @@
  *                     \/            \/     \/    \/            \/
  * $Id$
  *
- * Copyright (C) 2007 by Karl Kurbjun
+ * Copyright (C) 2008 by Maurus Cuelenaere
+ *
+ * DM320 I²C driver
  *
  * All files in this archive are subject to the GNU General Public License.
  * See the file COPYING in the source tree root for full license agreement.
@@ -17,39 +19,133 @@
  *
  ****************************************************************************/
 #include "system.h"
+#include "thread.h"
 #include "i2c-dm320.h"
 
-#if 0
-static int i2c_getack(void)
+#define I2C_SCS_COND_START  0x0001
+#define I2C_SCS_COND_STOP   0x0002
+#define I2C_SCS_XMIT        0x0004
+
+#define I2C_TX_ACK          (1 << 20)
+
+static struct mutex i2c_mtx;
+
+static inline void i2c_begin(void)
 {
-    return 0;
+    mutex_lock(&i2c_mtx);
 }
 
-static int i2c_start(void)
+static inline void i2c_end(void)
 {
-    return 0;
+    mutex_unlock(&i2c_mtx);
 }
 
-static void i2c_stop(void)
+static inline bool i2c_getack(void)
 {
+    return (IO_I2C_RXDATA & 0x100)>>8;
+}
+
+#define WAIT_FOR_I2C    if(IO_I2C_SCS & 0x4){ \
+                            while(IO_I2C_SCS & 0x4) { \
+                                asm volatile("nop"); \
+                            } \
+                        } \
 
+static inline void i2c_start(void)
+{
+    IO_I2C_SCS |= I2C_SCS_XMIT;
+    return;
 }
 
-static int i2c_outb(unsigned char byte)
+int i2c_write(unsigned short address, const unsigned char *buf, int count)
 {
-    (void) byte;
-    return 0;
+    int i;
+    int ret=0;
+    i2c_begin();
+    IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | (address>0x7F ? 0 : 1 ) | I2C_TX_ACK;
+    IO_I2C_SCS &= ~0x3; //clear conditions
+    IO_I2C_SCS |= I2C_SCS_COND_START; // write 'start condition'
+    i2c_start();
+    WAIT_FOR_I2C;
+    /* experimental */
+    if(address>0x7F){ // check if it is 10-bit instead of 7-bit
+        IO_I2C_TXDATA = ( (address >> 7) & 0xFF) | I2C_TX_ACK;
+        IO_I2C_SCS &= ~0x3; //normal transfer
+        i2c_start();
+        WAIT_FOR_I2C;
+        IO_I2C_TXDATA = ( (address << 1) & 0xFF) | 1 | I2C_TX_ACK;
+        IO_I2C_SCS &= ~0x3; //clear conditions
+        IO_I2C_SCS |= I2C_SCS_COND_START; //write 'start condition'
+        i2c_start();
+        WAIT_FOR_I2C;
+    }
+
+    for(i=0; i<count; i++){
+        IO_I2C_TXDATA = buf[i] | I2C_TX_ACK;
+        IO_I2C_SCS &= ~0x3; //normal transfer
+        i2c_start();
+        WAIT_FOR_I2C;
+        if(!i2c_getack())
+            ret = -1;
+    }
+    IO_I2C_SCS &= ~0x3; //clear conditions
+    IO_I2C_SCS |= I2C_SCS_COND_STOP; //write 'stop condition'
+    i2c_start();
+    WAIT_FOR_I2C;
+    i2c_end();
+    return ret;
 }
-#endif
 
-void i2c_write(int addr, const unsigned char *buf, int count)
+int i2c_read(unsigned short address, unsigned char* buf, int count)
 {
-    (void) addr;
-    (void) buf;
-    (void) count;
+    int i;
+    int ack=0;
+    i2c_begin();
+    IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | (address>0x7F ? 0 : 1 ) | I2C_TX_ACK;
+    IO_I2C_SCS &= ~0x3; //clear conditions
+    IO_I2C_SCS |= I2C_SCS_COND_START; // write 'start condition'
+    i2c_start();
+    WAIT_FOR_I2C;
+    /* experimental */
+    if(address>0x7F){ // check if it is 10-bit instead of 7-bit
+        IO_I2C_TXDATA = ( (address >> 7) & 0xFF ) | I2C_TX_ACK;
+        IO_I2C_SCS &= ~0x3; //normal transfer
+        i2c_start();
+        WAIT_FOR_I2C;
+        IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | 1 | I2C_TX_ACK;
+        IO_I2C_SCS &= ~0x3; //clear conditions
+        IO_I2C_SCS |= I2C_SCS_COND_START; //write 'start condition'
+        i2c_start();
+        WAIT_FOR_I2C;
+    }
+
+    for(i=0; i<count; i++){
+        unsigned short temp;
+        IO_I2C_TXDATA = 0xFF | ( (count-1)==i ? I2C_TX_ACK : 0);
+        IO_I2C_SCS &= ~0x3; //normal transfer
+        i2c_start();
+        WAIT_FOR_I2C;
+        temp = IO_I2C_RXDATA;
+        buf[i] = temp & 0xFF;
+        ack = (temp & 0x100) >> 8;
+    }
+    IO_I2C_SCS &= ~0x3; //clear conditions
+    IO_I2C_SCS |= I2C_SCS_COND_STOP; //write 'stop condition'
+    i2c_start();
+    WAIT_FOR_I2C;
+    i2c_end();
+    return ack;
 }
 
 void i2c_init(void)
 {
-
+#if 0 //TODO: mimic OF I2C clock settings; currently this is done by the bootloader
+    IO_CLK_MOD2 &= ~CLK_MOD2_I2C; // turn I²C clock off (just to be sure)
+    IO_CLK_LPCTL1 &= ~1; // set Powerdown mode to off
+    IO_CLK_SEL0 &= ~0x800; // set I²C clock to PLLA
+    IO_CLK_DIV4 &= ~0x1F; // I²C clock division = 1
+    IO_CLK_MOD2 |= CLK_MOD2_I2C; // enable I²C clock
+#endif
+    IO_I2C_SCS &= ~0x8; //set clock to 100 kHz
+    IO_INTC_EINT2 &= ~INTR_EINT2_I2C; // disable I²C interrupt
 }
diff --git a/firmware/target/arm/tms320dm320/i2c-dm320.h b/firmware/target/arm/tms320dm320/i2c-dm320.h
index aa7ced1119..d73a334eb4 100755
--- a/firmware/target/arm/tms320dm320/i2c-dm320.h
+++ b/firmware/target/arm/tms320dm320/i2c-dm320.h
@@ -5,9 +5,9 @@
  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
  *                     \/            \/     \/    \/            \/
- * $Id: i2c-meg-fx.h 13720 2007-06-26 02:11:30Z jethead71 $
+ * $Id$
  *
- * Copyright (C) 2007 by Michael Sevakis
+ * Copyright (C) 2008 by Maurus Cuelenaere
  *
  * All files in this archive are subject to the GNU General Public License.
  * See the file COPYING in the source tree root for full license agreement.
@@ -17,28 +17,6 @@
  *
  ****************************************************************************/
 
-/* chip-specific i2c functions */
-
-/* IICCON */
-#define I2C_ACKGEN          (1 << 7)
-#define I2C_TXCLK_512       (1 << 6)
-#define I2C_TXRX_INTENB     (1 << 5)
-#define I2C_TXRX_INTPND     (1 << 4)
-
-/* IICSTAT */
-#define I2C_MODE_MASTER     (2 << 6)
-#define I2C_MODE_TX         (1 << 6)
-#define I2C_BUSY            (1 << 5)
-#define I2C_START           (1 << 5)
-#define I2C_RXTX_ENB        (1 << 4)
-#define I2C_BUS_ARB_FAILED  (1 << 3)
-#define I2C_S_ADDR_STAT     (1 << 2)
-#define I2C_S_ADDR_MATCH    (1 << 1)
-#define I2C_ACK_L           (1 << 0)
-
-/* IICLC */
-#define I2C_FLT_ENB         (1 << 2)
-
 void i2c_init(void);
-void i2c_write(int addr, const unsigned char *data, int count);
-
+int i2c_write(unsigned short address, const unsigned char *data, int count);
+int i2c_read(unsigned short address, unsigned char* buf, int count);