Hi
2021. május 3., hétfő 1:28 keltezéssel, Emmanuel Gil Peyrot írta:
> On my DRC the values only go between 142 (battery LED blinking red
> before shutdown) and 178 (charge LED stopping), it seems to be the same
> on other units according to other testers.
>
> A spinlock is used to avoid the battery level and status from being
> reported unsynchronised.
>
> Signed-off-by: Emmanuel Gil Peyrot <linkmauve@xxxxxxxxxxxx>
> ---
> drivers/hid/hid-wiiu-drc.c | 107 +++++++++++++++++++++++++++++++++++++
> 1 file changed, 107 insertions(+)
>
> diff --git a/drivers/hid/hid-wiiu-drc.c b/drivers/hid/hid-wiiu-drc.c
> index 80faaaad2bb5..119d55542e31 100644
> --- a/drivers/hid/hid-wiiu-drc.c
> +++ b/drivers/hid/hid-wiiu-drc.c
> @@ -15,6 +15,8 @@
> #include <linux/device.h>
> #include <linux/hid.h>
> #include <linux/module.h>
> +#include <linux/power_supply.h>
> +#include <linux/spinlock.h>
> #include "hid-ids.h"
>
> #define DEVICE_NAME "Nintendo Wii U gamepad"
> @@ -69,6 +71,11 @@
> #define MAGNET_MIN ACCEL_MIN
> #define MAGNET_MAX ACCEL_MAX
>
> +/* Battery constants */
> +#define BATTERY_MIN 142
> +#define BATTERY_MAX 178
> +#define BATTERY_CAPACITY(val) ((val - BATTERY_MIN) * 100 / (BATTERY_MAX - BATTERY_MIN))
There's `fixp_linear_interpolate()` in linux/fixp-arithmetic.h,
you could use that.
> +
> /*
> * The device is setup with multiple input devices:
> * - A joypad with the buttons and sticks.
> @@ -77,10 +84,17 @@
> */
>
> struct drc {
> + spinlock_t lock;
I believe a `spin_lock_init()` call is missing from the code.
> +
> struct input_dev *joy_input_dev;
> struct input_dev *touch_input_dev;
> struct input_dev *accel_input_dev;
> struct hid_device *hdev;
> + struct power_supply *battery;
> + struct power_supply_desc battery_desc;
> +
> + u8 battery_energy;
> + int battery_status;
> };
>
> static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
> @@ -89,6 +103,7 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
> struct drc *drc = hid_get_drvdata(hdev);
> int i, x, y, z, pressure, base;
> u32 buttons;
> + unsigned long flags;
>
> if (len != 128)
> return 0;
> @@ -206,6 +221,17 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
> input_report_abs(drc->accel_input_dev, ABS_WHEEL, (int16_t)z);
> input_sync(drc->accel_input_dev);
>
> + /* battery */
> + spin_lock_irqsave(&drc->lock, flags);
> + drc->battery_energy = data[5];
> + if (drc->battery_energy == BATTERY_MAX)
> + drc->battery_status = POWER_SUPPLY_STATUS_FULL;
> + else if ((data[4] & 0x40) != 0)
Maybe `if (data[4] & BIT(BATTERY_CHARGING))` or `if (data[4] & BATTERY_CHARGING_BIT)`
would be better.
> + drc->battery_status = POWER_SUPPLY_STATUS_CHARGING;
> + else
> + drc->battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
> + spin_unlock_irqrestore(&drc->lock, flags);
> +
> /* let hidraw and hiddev handle the report */
> return 0;
> }
> @@ -309,10 +335,67 @@ static bool drc_setup_accel(struct drc *drc,
> return true;
> }
>
> +static enum power_supply_property drc_battery_props[] = {
> + POWER_SUPPLY_PROP_PRESENT,
> + POWER_SUPPLY_PROP_CAPACITY,
> + POWER_SUPPLY_PROP_SCOPE,
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_ENERGY_NOW,
> + POWER_SUPPLY_PROP_ENERGY_EMPTY,
> + POWER_SUPPLY_PROP_ENERGY_FULL,
> +};
> +
> +static int drc_battery_get_property(struct power_supply *psy,
> + enum power_supply_property psp,
> + union power_supply_propval *val)
> +{
> + struct drc *drc = power_supply_get_drvdata(psy);
> + unsigned long flags;
> + int ret = 0;
> + u8 battery_energy;
> + int battery_status;
> +
> + spin_lock_irqsave(&drc->lock, flags);
> + battery_energy = drc->battery_energy;
> + battery_status = drc->battery_status;
> + spin_unlock_irqrestore(&drc->lock, flags);
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_PRESENT:
> + val->intval = 1;
> + break;
> + case POWER_SUPPLY_PROP_SCOPE:
> + val->intval = POWER_SUPPLY_SCOPE_DEVICE;
> + break;
> + case POWER_SUPPLY_PROP_CAPACITY:
> + val->intval = BATTERY_CAPACITY(battery_energy);
> + break;
> + case POWER_SUPPLY_PROP_STATUS:
> + val->intval = battery_status;
> + break;
> + case POWER_SUPPLY_PROP_ENERGY_NOW:
> + val->intval = battery_energy;
> + break;
> + case POWER_SUPPLY_PROP_ENERGY_EMPTY:
> + val->intval = BATTERY_MIN;
> + break;
> + case POWER_SUPPLY_PROP_ENERGY_FULL:
> + val->intval = BATTERY_MAX;
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + return ret;
> +}
> +
> static bool drc_setup_joypad(struct drc *drc,
> struct hid_device *hdev)
> {
> struct input_dev *input_dev;
> + struct power_supply_config psy_cfg = { .drv_data = drc, };
> + int ret;
> + static uint8_t drc_num = 0;
You probably need an atomic integer here and use `atomic_fetch_inc()`
in the `devm_kasprintf()` call.
>
> input_dev = allocate_and_setup(hdev, DEVICE_NAME " Joypad");
> if (!input_dev)
> @@ -350,6 +433,30 @@ static bool drc_setup_joypad(struct drc *drc,
>
> drc->joy_input_dev = input_dev;
>
> + drc->battery_desc.properties = drc_battery_props;
> + drc->battery_desc.num_properties = ARRAY_SIZE(drc_battery_props);
> + drc->battery_desc.get_property = drc_battery_get_property;
> + drc->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
> + drc->battery_desc.use_for_apm = 0;
> +
> + /*
> + * TODO: It might be better to use the interface number as the drc_num,
> + * but I don’t know how to fetch it from here. In userland it is
> + * /sys/devices/platform/latte/d140000.usb/usb3/3-1/3-1:1.?/bInterfaceNumber
> + */
The interface number is not globally unique in any way as far as I can tell,
maybe the combination of the bus, port, device, interface numbers is.
> + drc->battery_desc.name = devm_kasprintf(&hdev->dev, GFP_KERNEL, "wiiu-drc-%i-battery", drc_num++);
> + if (!drc->battery_desc.name)
> + return -ENOMEM;
The function returns `bool`. You might want to change it to `int` and return
a proper errno.
> +
> + drc->battery = devm_power_supply_register(&hdev->dev, &drc->battery_desc, &psy_cfg);
> + if (IS_ERR(drc->battery)) {
> + ret = PTR_ERR(drc->battery);
> + hid_err(hdev, "Unable to register battery device\n");
> + return ret;
> + }
> +
> + power_supply_powers(drc->battery, &hdev->dev);
> +
> return true;
> }
>
> --
> 2.31.1
Regards,
Barnabás Pőcze
