Vaibhav Hiremath <vaibhav.hirem...@linaro.org> writes:
> #define _IBMR(i2c) ((i2c)->reg_ibmr)
> @@ -286,6 +287,22 @@ static void i2c_pxa_scream_blue_murder(struct pxa_i2c
> *i2c, const char *why)
> static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
> static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
>
> +/* enable/disable i2c unit */
> +static inline int i2c_pxa_is_enabled(struct pxa_i2c *i2c)
> +{
> + return (readl(_ICR(i2c)) & ICR_IUE);
> +}
> +
> +static inline void i2c_pxa_enable(struct pxa_i2c *i2c, bool enable)
> +{
> + if (enable && !i2c_pxa_is_enabled(i2c)) {
> + writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
> + udelay(100);
> + } else {
> + writel(readl(_ICR(i2c)) & ~ICR_IUE, _ICR(i2c));
> + }
> +}
> +
> static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
> {
> return !(readl(_ICR(i2c)) & ICR_SCLE);
> @@ -482,8 +499,7 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
> i2c_pxa_set_slave(i2c, 0);
>
> /* enable unit */
> - writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
> - udelay(100);
> + i2c_pxa_enable(i2c, true);
> }
>
>
> @@ -840,6 +856,9 @@ static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
> struct pxa_i2c *i2c = adap->algo_data;
> int ret, i;
>
> + /* Enable i2c unit */
> + i2c_pxa_enable(i2c, true);
> +
> /* If the I2C controller is disabled we need to reset it
> (probably due to a suspend/resume destroying state). We do
> this here as we can then avoid worrying about resuming the
> @@ -860,6 +879,11 @@ static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
> ret = -EREMOTEIO;
> out:
> i2c_pxa_set_slave(i2c, ret);
> +
> + /* disable i2c unit */
> + if (i2c->disable_after_xfer)
> + i2c_pxa_enable(i2c, false);
> +
> return ret;
> }
>
> @@ -1075,6 +1099,9 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap,
> struct i2c_msg msgs[], int num
> struct pxa_i2c *i2c = adap->algo_data;
> int ret, i;
>
> + /* Enable i2c unit */
> + i2c_pxa_enable(i2c, true);
Okay, what happens in master mode when we get there on the 2nd xfer :
- i2c is enabled AFAIU.
- as a consequence i2c_pxa_is_enabled() returns true
- as a consequence, i2c_pxa_enable() _disables_ the i2c, right ?
- as a consequence i2c is broken
Is this correct, because if it is the patch needs a rework ?
Cheers.
--
Robert
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
