Re: [PATCH v6 07/15] platform/x86: int3472: Enable I2c daisy chain

Laurent Pinchart
2021-11-25T23:41:30Z

Hi Hans,

Thank you for the patch.

On Thu, Nov 25, 2021 at 05:54:04PM +0100, Hans de Goede wrote:
> From: Daniel Scally <djrscally@gmail.com>
>
> The TPS68470 PMIC has an I2C passthrough mode through which I2C traffic
> can be forwarded to a device connected to the PMIC as though it were
> connected directly to the system bus. Enable this mode when the chip
> is initialised.

Is there any drawback doing this unconditionally, if nothing is
connected to the bus on the other side (including no pull-ups) ?

> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Signed-off-by: Daniel Scally <djrscally@gmail.com>
> ---
> .../x86/intel/int3472/intel_skl_int3472_tps68470.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/platform/x86/intel/int3472/intel_skl_int3472_tps68470.c b/drivers/platform/x86/intel/int3472/intel_skl_int3472_tps68470.c
> index c05b4cf502fe..42e688f4cad4 100644
> --- a/drivers/platform/x86/intel/int3472/intel_skl_int3472_tps68470.c
> +++ b/drivers/platform/x86/intel/int3472/intel_skl_int3472_tps68470.c
> @@ -45,6 +45,13 @@ static int tps68470_chip_init(struct device *dev, struct regmap *regmap)
> return ret;
> }
>
> + /* Enable I2C daisy chain */
> + ret = regmap_write(regmap, TPS68470_REG_S_I2C_CTL, 0x03);
> + if (ret) {
> + dev_err(dev, "Failed to enable i2c daisy chain\n");
> + return ret;
> + }
> +
> dev_info(dev, "TPS68470 REVID: 0x%02x\n", version);
>
> return 0;

--
Regards,

Laurent Pinchart