From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Mon, 18 Jan 2016 06:59:43 +0100 Subject: [U-Boot] [PATCH 2/5] i2c: omap24xx: Fix waitdelay value for I2C HS In-Reply-To: <1453028992-14220-3-git-send-email-christophe-h.ricard@st.com> References: <1453028992-14220-1-git-send-email-christophe-h.ricard@st.com> <1453028992-14220-3-git-send-email-christophe-h.ricard@st.com> Message-ID: <569C7F4F.5050407@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Christophe, Am 17.01.2016 um 12:09 schrieb Christophe Ricard: > After several testings and experiment, it appears that waitdelay calculation > formula was giving different behavior on the i2c status registers. > > Experiment shows waitdelay needs to be extended at least 4 times to get > proper results. > > Signed-off-by: Christophe Ricard > --- > > drivers/i2c/omap24xx_i2c.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c > index f3a4d96..d6e5fe9 100644 > --- a/drivers/i2c/omap24xx_i2c.c > +++ b/drivers/i2c/omap24xx_i2c.c > @@ -168,6 +168,13 @@ static int omap24_i2c_setspeed(struct udevice *adap, unsigned int speed) > scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll; > sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh; > > +#ifdef CONFIG_SYS_I2C > + adap->speed = speed; > + adap->waitdelay = (10000000 / speed) * 8; /* wait for 20 clkperiods */ > +#else > + i2c_bus->clock_frequency = speed; > + i2c_bus->waitdelay = (10000000 / speed) * 8; /* wait for 20 clkperiods */ > +#endif > } else { > /* Standard and fast speed */ > psc = omap24_i2c_findpsc(&scll, &sclh, speed); > @@ -175,15 +182,15 @@ static int omap24_i2c_setspeed(struct udevice *adap, unsigned int speed) > puts("Error : I2C initializing clock\n"); > return -1; > } > - } > > #ifdef CONFIG_SYS_I2C > - adap->speed = speed; > - adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */ > + adap->speed = speed; > + adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */ > #else > - i2c_bus->clock_frequency = speed; > - i2c_bus->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */ > + i2c_bus->clock_frequency = speed; > + i2c_bus->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */ > #endif > + } You change here only the "speed >= OMAP_I2C_HIGH_SPEED" case ... Is this your intention? If so, please add this info in your commit message. Beside of this nitpick: Acked-by: Heiko Schocher bye, Heiko > > writew(0, &i2c_base->con); > writew(psc, &i2c_base->psc); > @@ -467,7 +474,6 @@ static int omap24_i2c_read(struct udevice *adap, uchar chip, uint addr, > i2c_bus = dev_get_priv(adap); > i2c_base = i2c_bus->i2c_base; > #endif > - > if (alen < 0) { > puts("I2C read: addr len < 0\n"); > return 1; > -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany