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	<3609d98d4603efab7b2e50635efa9e36f64017a8.1458822334.git.baolin.wang@linaro.org>
Date: Sun, 27 Mar 2016 10:22:37 +0200
Message-ID: <CAMuHMdVUwbp4bJDYWjw6QyfngxYJgJCBe4=DN53tpFhjxUagcA@mail.gmail.com>
Subject: Re: [PATCH v8 4/4] power: wm831x_power: Support USB charger current
 limit management
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Baolin Wang <baolin.wang@linaro.org>
Cc: Felipe Balbi <balbi@kernel.org>, Greg KH <gregkh@linuxfoundation.org>,
        Sebastian Reichel <sre@kernel.org>,
        Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>,
        David Woodhouse <dwmw2@infradead.org>,
        Peter Chen <peter.chen@freescale.com>,
        Alan Stern <stern@rowland.harvard.edu>, r.baldyga@samsung.com,
        Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
        Lee Jones <lee.jones@linaro.org>, Mark Brown <broonie@kernel.org>,
        Charles Keepax <ckeepax@opensource.wolfsonmicro.com>,
        patches@opensource.wolfsonmicro.com,
        Linux PM list <linux-pm@vger.kernel.org>,
        USB list <linux-usb@vger.kernel.org>,
        device-mainlining@lists.linuxfoundation.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Thu, Mar 24, 2016 at 1:35 PM, Baolin Wang <baolin.wang@linaro.org> wrote:
> --- a/drivers/power/wm831x_power.c
> +++ b/drivers/power/wm831x_power.c
> @@ -13,6 +13,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/power_supply.h>
>  #include <linux/slab.h>
> +#include <linux/usb/usb_charger.h>
>
>  #include <linux/mfd/wm831x/core.h>
>  #include <linux/mfd/wm831x/auxadc.h>
> @@ -31,6 +32,8 @@ struct wm831x_power {
>         char usb_name[20];
>         char battery_name[20];
>         bool have_battery;
> +       struct usb_charger *usb_charger;
> +       struct notifier_block usb_notify;
>  };
>
>  static int wm831x_power_check_online(struct wm831x *wm831x, int supply,
> @@ -125,6 +128,43 @@ static enum power_supply_property wm831x_usb_props[] = {
>         POWER_SUPPLY_PROP_VOLTAGE_NOW,
>  };
>
> +/* In milliamps */
> +static unsigned int wm831x_usb_limits[] = {

const

> +       0,
> +       2,
> +       100,
> +       500,
> +       900,
> +       1500,
> +       1800,
> +       550,
> +};
> +
> +static int wm831x_usb_limit_change(struct notifier_block *nb,
> +                                  unsigned long limit, void *data)
> +{
> +       struct wm831x_power *wm831x_power = container_of(nb,
> +                                                        struct wm831x_power,
> +                                                        usb_notify);
> +       int i, best;

unsigned int

> +
> +       /* Find the highest supported limit */
> +       best = 0;
> +       for (i = 0; i < ARRAY_SIZE(wm831x_usb_limits); i++) {
> +               if (limit >= wm831x_usb_limits[i] &&
> +                   wm831x_usb_limits[best] < wm831x_usb_limits[i])
> +                       best = i;
> +       }
> +
> +       dev_dbg(wm831x_power->wm831x->dev,
> +               "Limiting USB current to %dmA", wm831x_usb_limits[best]);

%u

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds