Re: [U-Boot] [PATCH 4/5] i2c: omap24xx: Fix high speed trimming calculation

Hello Christophe,

Am 17.01.2016 um 12:09 schrieb Christophe Ricard:

Work based on i2c-omap.c from linux kernel.

fsscll/fssclh and hsscll/hssclh was always negative in high speed.

i2c high speed frequency start after 400Khz.

Signed-off-by: Christophe Ricard christophe-h.ricard@st.com

drivers/i2c/omap24xx_i2c.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c index 48ca446..774edaf 100644 --- a/drivers/i2c/omap24xx_i2c.c +++ b/drivers/i2c/omap24xx_i2c.c @@ -129,7 +129,9 @@ static int omap24_i2c_setspeed(struct udevice *adap, unsigned int speed) i2c_base = i2c_bus->i2c_base; #endif

• if (speed >= OMAP_I2C_HIGH_SPEED) {

• if (speed > 400000) {

Why you remove the define?

• unsigned long scl;
  

• /* High speed */ psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK; psc -= 1;

@@ -139,12 +141,11 @@ static int omap24_i2c_setspeed(struct udevice *adap, unsigned int speed) }

/* For first phase of HS mode */

• fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
  

• scl = I2C_INTERNAL_SAMPLING_CLK / 400000;
  
  

• fssclh = fsscll;
  

• fsscll = scl - (scl / 3) - 7;
  

• fssclh = (scl / 3)  - 5;
  
  

• fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
  

• fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
  

  if (((fsscll < 0) || (fssclh < 0)) || ((fsscll > 255) || (fssclh > 255))) { puts("Error : I2C initializing first phase clock\n");

@@ -152,10 +153,10 @@ static int omap24_i2c_setspeed(struct udevice *adap, unsigned int speed) }

/* For second phase of HS mode */

• hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
  

• scl = I2C_IP_CLK / speed;
  

• hsscll = scl - (scl / 3) - 7;
  

• hssclh = (scl / 3) - 5;
  
  

• hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM;
  

• hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM;
  

  if (((fsscll < 0) || (fssclh < 0)) || ((fsscll > 255) || (fssclh > 255))) { puts("Error : I2C initializing second phase clock\n");

Reviewed-by: Heiko Schocher hs@denx.de

bye, Heiko