Re: [PATCH 5/5] extcon: intel-cht-wc: Add support for monitoring external USB Type-C controller

[Andy Shevchenko <andy.shevchenko@gmail.com>]

+Cc: Heikki,

On Fri, Apr 21, 2017 at 4:01 PM, Hans de Goede <hdegoede@redhat.com> wrote:
> On some boards the Whiskey Cove PMIC is combined with an external USB
> Type-C controller, in this case extcon consumers should use the Type-C
> extcon state, except when the USB Type-C controller detects a current
> limit of 500 mA which may indicate USB-C to USB-A cable at which point
> the extcon consumer should use the Whiskey Cove's BC-1.2 detection's
> state.
>
> Since the Type-C controller info is incomplete and needs to be
> supplemented with the BC1.2 detection result in some cases, this
> commit makes the intel-cht-wc extcon driver monitor the extcon device
> registered by the Type-C controller and report that as our extcon state
> except when BC-1.2 detection should be used. This allows extcon
> consumers on these boards to keep monitoring only the intel-cht-wc extcon
> and then get complete extcon info from that, which combines the Type-C
> and BC-1.2 info.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/extcon/extcon-intel-cht-wc.c | 96 ++++++++++++++++++++++++++++++------
>  1 file changed, 80 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/extcon/extcon-intel-cht-wc.c b/drivers/extcon/extcon-intel-cht-wc.c
> index 684f6b2..e510188 100644
> --- a/drivers/extcon/extcon-intel-cht-wc.c
> +++ b/drivers/extcon/extcon-intel-cht-wc.c
> @@ -15,6 +15,7 @@
>   * more details.
>   */
>
> +#include <linux/acpi.h>
>  #include <linux/extcon.h>
>  #include <linux/interrupt.h>
>  #include <linux/kernel.h>
> @@ -88,6 +89,7 @@ static const unsigned int cht_wc_extcon_cables[] = {
>         EXTCON_CHG_USB_CDP,
>         EXTCON_CHG_USB_DCP,
>         EXTCON_CHG_USB_ACA,
> +       EXTCON_CHG_USB_FAST,
>         EXTCON_NONE,
>  };
>
> @@ -95,6 +97,9 @@ struct cht_wc_extcon_data {
>         struct device *dev;
>         struct regmap *regmap;
>         struct extcon_dev *edev;
> +       struct extcon_dev *usbc;
> +       struct notifier_block usbc_nb;
> +       struct work_struct work;
>         unsigned int previous_cable;
>         bool usb_host;
>  };
> @@ -224,8 +229,32 @@ static void cht_wc_extcon_set_state(struct cht_wc_extcon_data *ext,
>         extcon_set_state_sync(ext->edev, EXTCON_USB_HOST, ext->usb_host);
>  }
>
> -static void cht_wc_extcon_pwrsrc_event(struct cht_wc_extcon_data *ext)
> +static void cht_wc_extcon_usb_c_event(struct work_struct *work)
>  {
> +       struct cht_wc_extcon_data *ext =
> +               container_of(work, struct cht_wc_extcon_data, work);
> +       unsigned int cable = EXTCON_NONE;
> +
> +       if (extcon_get_state(ext->usbc, EXTCON_CHG_USB_SDP) > 0) {
> +               /*
> +                * USB-C to USB-A cable ? Try BC1.2 charger detection from
> +                * WC PMIC, ignore charger detection errors.
> +                */
> +               cable = cht_wc_extcon_get_charger(ext, true);
> +       } else if (extcon_get_state(ext->usbc, EXTCON_CHG_USB_CDP) > 0) {
> +               cable = EXTCON_CHG_USB_CDP;
> +       } else if (extcon_get_state(ext->usbc, EXTCON_CHG_USB_FAST) > 0) {
> +               cable = EXTCON_CHG_USB_FAST;
> +       }
> +
> +       ext->usb_host = (extcon_get_state(ext->usbc, EXTCON_USB_HOST) > 0);
> +       cht_wc_extcon_set_state(ext, cable);
> +}
> +
> +static void cht_wc_extcon_pwrsrc_event(struct work_struct *work)
> +{
> +       struct cht_wc_extcon_data *ext =
> +               container_of(work, struct cht_wc_extcon_data, work);
>         int ret, pwrsrc_sts, id;
>         unsigned int cable = EXTCON_NONE;
>         /* Ignore errors in host mode, as the 5v boost converter is on then */
> @@ -258,7 +287,7 @@ static irqreturn_t cht_wc_extcon_isr(int irq, void *data)
>                 return IRQ_NONE;
>         }
>
> -       cht_wc_extcon_pwrsrc_event(ext);
> +       schedule_work(&ext->work);
>
>         ret = regmap_write(ext->regmap, CHT_WC_PWRSRC_IRQ, irqs);
>         if (ret) {
> @@ -269,6 +298,17 @@ static irqreturn_t cht_wc_extcon_isr(int irq, void *data)
>         return IRQ_HANDLED;
>  }
>
> +static int cht_wc_extcon_usbc_evt(struct notifier_block *nb,
> +                                 unsigned long event, void *param)
> +{
> +       struct cht_wc_extcon_data *ext =
> +               container_of(nb, struct cht_wc_extcon_data, usbc_nb);
> +
> +       schedule_work(&ext->work);
> +
> +       return NOTIFY_OK;
> +}
> +
>  static int cht_wc_extcon_sw_control(struct cht_wc_extcon_data *ext, bool enable)
>  {
>         int ret, mask, val;
> @@ -300,6 +340,15 @@ static int cht_wc_extcon_probe(struct platform_device *pdev)
>         ext->regmap = pmic->regmap;
>         ext->previous_cable = EXTCON_NONE;
>
> +       if (acpi_dev_present("INT33FE", NULL, -1)) {
> +               ext->usbc = extcon_get_extcon_dev("fusb302");
> +               if (!ext->usbc)
> +                       return -EPROBE_DEFER;
> +
> +               dev_info(&pdev->dev,
> +                        "Using FUSB302 extcon for USB Type-C cable info\n");
> +       }
> +
>         /* Initialize extcon device */
>         ext->edev = devm_extcon_dev_allocate(ext->dev, cht_wc_extcon_cables);
>         if (IS_ERR(ext->edev))
> @@ -335,25 +384,40 @@ static int cht_wc_extcon_probe(struct platform_device *pdev)
>         /* Route D+ and D- to PMIC for initial charger detection */
>         cht_wc_extcon_set_phymux(ext, MUX_SEL_PMIC);
>
> -       /* Get initial state */
> -       cht_wc_extcon_pwrsrc_event(ext);
> -
> -       ret = devm_request_threaded_irq(ext->dev, irq, NULL, cht_wc_extcon_isr,
> -                                       IRQF_ONESHOT, pdev->name, ext);
> -       if (ret) {
> -               dev_err(ext->dev, "Error requesting interrupt: %d\n", ret);
> -               goto disable_sw_control;
> -       }
> +       if (ext->usbc) {
> +               INIT_WORK(&ext->work, cht_wc_extcon_usb_c_event);
> +               ext->usbc_nb.notifier_call = cht_wc_extcon_usbc_evt;
> +               ret = devm_extcon_register_notifier_all(&pdev->dev, ext->usbc,
> +                                                       &ext->usbc_nb);
> +               if (ret) {
> +                       dev_err(&pdev->dev,
> +                               "Error registering usbc extcon notifier: %d\n",
> +                               ret);
> +                       goto disable_sw_control;
> +               }
> +       } else {
> +               INIT_WORK(&ext->work, cht_wc_extcon_pwrsrc_event);
> +               ret = devm_request_threaded_irq(ext->dev, irq, NULL,
> +                                               cht_wc_extcon_isr, IRQF_ONESHOT,
> +                                               pdev->name, ext);
> +               if (ret) {
> +                       dev_err(ext->dev, "Error requesting irq: %d\n", ret);
> +                       goto disable_sw_control;
> +               }
>
> -       /* Unmask irqs */
> -       ret = regmap_write(ext->regmap, CHT_WC_PWRSRC_IRQ_MASK,
> +               /* Unmask irqs */
> +               ret = regmap_write(ext->regmap, CHT_WC_PWRSRC_IRQ_MASK,
>                            (int)~(CHT_WC_PWRSRC_VBUS | CHT_WC_PWRSRC_ID_GND |
>                                   CHT_WC_PWRSRC_ID_FLOAT));
> -       if (ret) {
> -               dev_err(ext->dev, "Error writing irq-mask: %d\n", ret);
> -               goto disable_sw_control;
> +               if (ret) {
> +                       dev_err(ext->dev, "Error writing irq-mask: %d\n", ret);
> +                       goto disable_sw_control;
> +               }
>         }
>
> +       /* Get initial state */
> +       schedule_work(&ext->work);
> +
>         platform_set_drvdata(pdev, ext);
>
>         return 0;
> --
> 2.9.3
>



-- 
With Best Regards,
Andy Shevchenko