| Message ID | 1436210695-19159-3-git-send-email-vaibhav.hiremath@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Friday 10 July 2015 01:41 PM, Wolfram Sang wrote: > On Tue, Jul 07, 2015 at 12:54:46AM +0530, Vaibhav Hiremath wrote: >> Normally i2c controller works as master, so slave addr is not needed, or it >> will impact some slave device (eg. ST NFC chip) i2c accesses, because it has >> the same i2c address with controller. > > Just to make sure: Does it? As I read the code, slave interrupts are > enabled later only when slave mode is selected? Is that a HW bug? And if > so, can't the code just be moved into this #ifdef block later? > Yes we could, infact I thought about it; but I would break recommended sequence here. As per spec, it only says, The SocC writes this register before it enable TWSI operations. I decided not to break the existing sequence and just fix the code, as I do can not validate slave mode of operation functionally. I do not have slave mode setup with me. Thanks, Vaibhav >> >> Signed-off-by: Jett.Zhou <jtzhou@marvell.com> >> Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org> >> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> >> --- >> drivers/i2c/busses/i2c-pxa.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c >> index f4ac8c5..023e59f 100644 >> --- a/drivers/i2c/busses/i2c-pxa.c >> +++ b/drivers/i2c/busses/i2c-pxa.c >> @@ -459,7 +459,7 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c) >> writel(I2C_ISR_INIT, _ISR(i2c)); >> writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c)); >> >> - if (i2c->reg_isar) >> + if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE)) >> writel(i2c->slave_addr, _ISAR(i2c)); >> >> /* set control register values */ >> -- >> 1.9.1 >> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Friday 10 July 2015 08:26 PM, Wolfram Sang wrote: > On Fri, Jul 10, 2015 at 07:55:31PM +0530, Vaibhav Hiremath wrote: >> >> >> On Friday 10 July 2015 07:44 PM, Wolfram Sang wrote: >>> On Fri, Jul 10, 2015 at 06:08:43PM +0530, Vaibhav Hiremath wrote: >>>> >>>> >>>> On Friday 10 July 2015 01:41 PM, Wolfram Sang wrote: >>>>> On Tue, Jul 07, 2015 at 12:54:46AM +0530, Vaibhav Hiremath wrote: >>>>>> Normally i2c controller works as master, so slave addr is not needed, or it >>>>>> will impact some slave device (eg. ST NFC chip) i2c accesses, because it has >>>>>> the same i2c address with controller. >>>>> >>>>> Just to make sure: Does it? As I read the code, slave interrupts are >>>>> enabled later only when slave mode is selected? Is that a HW bug? And if >>>>> so, can't the code just be moved into this #ifdef block later? >>>>> >>>> >>>> Yes we could, infact I thought about it; >>>> but I would break recommended sequence here. >>> >>> And did you set the "own slave address" to a value which one of your >>> existing i2c slaves also has (without enabling slave mode)? Did it >>> disturb communication? >>> >> >> Since slave and master mode are mutual exclusive, >> I did not try this. > > Ehrm, what I meant was. Did you see the issue mentioned in the above > commit message? Can you reproduce it? You don't need to enable slave > mode for that, no? > Ohh yes, I am able to reproduce this issue. I have pxa1928 based board, where I have only PMIC 88PM860 connected to I2C bus, and whenever I set slave address to 0x30 (PMIC slave address) all I2C transaction for PMIC goes for toss. Thanks, Vaibhav -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index f4ac8c5..023e59f 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -459,7 +459,7 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c) writel(I2C_ISR_INIT, _ISR(i2c)); writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c)); - if (i2c->reg_isar) + if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE)) writel(i2c->slave_addr, _ISAR(i2c)); /* set control register values */