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soft_i2c: Add CFG_I2C_INIT_BOARD option 

This patch adds the option for a boardspecific
I2C deblocking mechanism for the soft i2c driver.

Signed-off-by: Heiko Schocher <hs@denx.de>
This commit is contained in:
Heiko Schocher 2008-10-15 09:38:38 +02:00 committed by Wolfgang Denk
parent e5e4edd9f1
commit 4ca107effe
1 changed files with 11 additions and 0 deletions
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11
drivers/i2c/soft_i2c.c
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@ -75,13 +75,16 @@ static unsigned int i2c_bus_num __attribute__ ((section ("data"))) = 0;
/*----------------------------------------------------------------------- /*-----------------------------------------------------------------------
* Local functions * Local functions
*/ */
#if !defined(CFG_I2C_INIT_BOARD)
static void send_reset (void); static void send_reset (void);
#endif
static void send_start (void); static void send_start (void);
static void send_stop (void); static void send_stop (void);
static void send_ack (int); static void send_ack (int);
static int write_byte (uchar byte); static int write_byte (uchar byte);
static uchar read_byte (int); static uchar read_byte (int);
#if !defined(CFG_I2C_INIT_BOARD)
/*----------------------------------------------------------------------- /*-----------------------------------------------------------------------
* Send a reset sequence consisting of 9 clocks with the data signal high * Send a reset sequence consisting of 9 clocks with the data signal high
* to clock any confused device back into an idle state. Also send a * to clock any confused device back into an idle state. Also send a
@ -109,6 +112,7 @@ static void send_reset(void)
send_stop(); send_stop();
I2C_TRISTATE; I2C_TRISTATE;
} }
#endif
/*----------------------------------------------------------------------- /*-----------------------------------------------------------------------
* START: High -> Low on SDA while SCL is High * START: High -> Low on SDA while SCL is High
@ -280,6 +284,12 @@ static uchar read_byte(int ack)
*/ */
void i2c_init (int speed, int slaveaddr) void i2c_init (int speed, int slaveaddr)
{ {
#if defined(CFG_I2C_INIT_BOARD)
/* call board specific i2c bus reset routine before accessing the */
/* environment, which might be in a chip on that bus. For details */
/* about this problem see doc/I2C_Edge_Conditions. */
i2c_init_board();
#else
/* /*
* WARNING: Do NOT save speed in a static variable: if the * WARNING: Do NOT save speed in a static variable: if the
* I2C routines are called before RAM is initialized (to read * I2C routines are called before RAM is initialized (to read
@ -287,6 +297,7 @@ void i2c_init (int speed, int slaveaddr)
* system will crash. * system will crash.
*/ */
send_reset (); send_reset ();
#endif
} }
/*----------------------------------------------------------------------- /*-----------------------------------------------------------------------