Re: [PATCH v2 16/20] extcon: intel-cht-wc: Use new intel_cht_wc_get_model() helper

Chanwoo Choi
2021-11-17T06:47:09Z

On 21. 11. 15. 오전 2:03, Hans de Goede wrote:
> The CHT_WC_VBUS_GPIO_CTLO GPIO actually driving an external 5V Vboost
> converter for Vbus depends on the board on which the Cherry Trail -
> Whiskey Cove PMIC is actually used.
>
> Since the information about the exact PMIC setup is necessary in other
> places too, the drivers/mfd/intel_soc_pmic_chtwc.c code now has a new
> intel_cht_wc_get_model() helper.
>
> Only poke the CHT_WC_VBUS_GPIO_CTLO GPIO if this new helper returns
> INTEL_CHT_WC_GPD_WIN_POCKET, which indicates the Type-C (with PD and
> DP-altmode) setup used on the GPD pocket and GPD win; and on which
> this GPIO actually controls an external 5V Vboost converter.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> drivers/extcon/extcon-intel-cht-wc.c | 35 +++++++++++++++++-----------
> 1 file changed, 21 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/extcon/extcon-intel-cht-wc.c b/drivers/extcon/extcon-intel-cht-wc.c
> index 771f6f4cf92e..a5aeeecc44fb 100644
> --- a/drivers/extcon/extcon-intel-cht-wc.c
> +++ b/drivers/extcon/extcon-intel-cht-wc.c
> @@ -14,6 +14,7 @@
> #include <linux/module.h>
> #include <linux/mod_devicetable.h>
> #include <linux/platform_device.h>
> +#include <linux/property.h>
> #include <linux/regmap.h>
> #include <linux/slab.h>
>
> @@ -358,20 +359,26 @@ static int cht_wc_extcon_probe(struct platform_device *pdev)
> if (IS_ERR(ext->edev))
> return PTR_ERR(ext->edev);
>
> - /*
> - * When a host-cable is detected the BIOS enables an external 5v boost
> - * converter to power connected devices there are 2 problems with this:
> - * 1) This gets seen by the external battery charger as a valid Vbus
> - * supply and it then tries to feed Vsys from this creating a
> - * feedback loop which causes aprox. 300 mA extra battery drain
> - * (and unless we drive the external-charger-disable pin high it
> - * also tries to charge the battery causing even more feedback).
> - * 2) This gets seen by the pwrsrc block as a SDP USB Vbus supply
> - * Since the external battery charger has its own 5v boost converter
> - * which does not have these issues, we simply turn the separate
> - * external 5v boost converter off and leave it off entirely.
> - */
> - cht_wc_extcon_set_5v_boost(ext, false);
> + switch (intel_cht_wc_get_model()) {

intel_cht_wc_get_model() is defined in driver/mfd/intel_soc_pmic_chtwc.c

Usually, mfd drivers share the data structure such as struct
intel_soc_pmic. But, didn't call the exported function for only
specific driver between linux kernel framework (extcon vs. mfd).

So that I think that you better to update the mode information
to 'struct intel_soc_pmic' data structure and then use it
instead of using the exported function which may make the confusion.

> + case INTEL_CHT_WC_GPD_WIN_POCKET:
> + /*
> + * When a host-cable is detected the BIOS enables an external 5v boost
> + * converter to power connected devices there are 2 problems with this:
> + * 1) This gets seen by the external battery charger as a valid Vbus
> + * supply and it then tries to feed Vsys from this creating a
> + * feedback loop which causes aprox. 300 mA extra battery drain
> + * (and unless we drive the external-charger-disable pin high it
> + * also tries to charge the battery causing even more feedback).
> + * 2) This gets seen by the pwrsrc block as a SDP USB Vbus supply
> + * Since the external battery charger has its own 5v boost converter
> + * which does not have these issues, we simply turn the separate
> + * external 5v boost converter off and leave it off entirely.
> + */
> + cht_wc_extcon_set_5v_boost(ext, false);
> + break;
> + default:
> + break;
> + }
>
> /* Enable sw control */
> ret = cht_wc_extcon_sw_control(ext, true);
>

--
Best Regards,
Samsung Electronics
Chanwoo Choi