diff options
Diffstat (limited to 'drivers/i2c/omap24xx_i2c.c')
| -rw-r--r-- | drivers/i2c/omap24xx_i2c.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c index a39b5917ec..0f1e35c460 100644 --- a/drivers/i2c/omap24xx_i2c.c +++ b/drivers/i2c/omap24xx_i2c.c @@ -153,11 +153,60 @@ static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed) return 0; } + +static void omap24_i2c_deblock(struct i2c_adapter *adap) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int i; + u16 systest; + u16 orgsystest; + + /* set test mode ST_EN = 1 */ + orgsystest = readw(&i2c_base->systest); + systest = orgsystest; + /* enable testmode */ + systest |= I2C_SYSTEST_ST_EN; + writew(systest, &i2c_base->systest); + systest &= ~I2C_SYSTEST_TMODE_MASK; + systest |= 3 << I2C_SYSTEST_TMODE_SHIFT; + writew(systest, &i2c_base->systest); + + /* set SCL, SDA = 1 */ + systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O; + writew(systest, &i2c_base->systest); + udelay(10); + + /* toggle scl 9 clocks */ + for (i = 0; i < 9; i++) { + /* SCL = 0 */ + systest &= ~I2C_SYSTEST_SCL_O; + writew(systest, &i2c_base->systest); + udelay(10); + /* SCL = 1 */ + systest |= I2C_SYSTEST_SCL_O; + writew(systest, &i2c_base->systest); + udelay(10); + } + + /* send stop */ + systest &= ~I2C_SYSTEST_SDA_O; + writew(systest, &i2c_base->systest); + udelay(10); + systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O; + writew(systest, &i2c_base->systest); + udelay(10); + + /* restore original mode */ + writew(orgsystest, &i2c_base->systest); +} + static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd) { struct i2c *i2c_base = omap24_get_base(adap); int timeout = I2C_TIMEOUT; + int deblock = 1; +retry: if (readw(&i2c_base->con) & I2C_CON_EN) { writew(0, &i2c_base->con); udelay(50000); @@ -194,6 +243,14 @@ static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd) udelay(1000); flush_fifo(adap); writew(0xFFFF, &i2c_base->stat); + + /* Handle possible failed I2C state */ + if (wait_for_bb(adap)) + if (deblock == 1) { + omap24_i2c_deblock(adap); + deblock = 0; + goto retry; + } } static void flush_fifo(struct i2c_adapter *adap) |
