RE: [PATCH 1/1] Input: joydev - blacklist ds3/ds4/udraw motion sensors

["Colenbrander, Roelof" <Roderick.Colenbrander@xxxxxxxx>]

Hi Dmitry,

Thanks for your suggestions the feedback looks good. Just got back to office after a long weekend, then was surprised to see you already made a few changes to the series. The changes look. Thanks for the assistance!

Thanks,
Roderick
________________________________________
From: Dmitry Torokhov [dmitry.torokhov@xxxxxxxxx]
Sent: Saturday, October 07, 2017 11:44 AM
To: roderick@xxxxxxxxxx
Cc: linux-input@xxxxxxxxxxxxxxx; Benjamin Tissoires; Jiri Kosina; Colenbrander, Roelof; stable@xxxxxxxxxxxxxxx
Subject: Re: [PATCH 1/1] Input: joydev - blacklist ds3/ds4/udraw motion sensors

Hi Roderick,

On Thu, Oct 05, 2017 at 06:03:33PM -0700, Roderick Colenbrander wrote:
> From: Roderick Colenbrander <roderick.colenbrander@xxxxxxxx>
>
> Introduce a device table used for blacklisting devices. We currently
> blacklist the motion sensor subdevice of THQ Udraw and Sony ds3/ds4.
>
> Signed-off-by: Roderick Colenbrander <roderick.colenbrander@xxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
>  drivers/input/joydev.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 57 insertions(+)
>
> diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c
> index 29d677c714d2..e2a0f63d5656 100644
> --- a/drivers/input/joydev.c
> +++ b/drivers/input/joydev.c
> @@ -70,6 +70,40 @@ struct joydev_client {
>       struct list_head node;
>  };
>
> +/* These codes are copied from from hid-ids.h, unfortunately there is no common
> + * usb_ids/bt_ids.h header.
> + */
> +#define USB_VENDOR_ID_SONY 0x54c
> +#define USB_VENDOR_ID_THQ            0x20d6
> +#define USB_DEVICE_ID_SONY_PS3_CONTROLLER    0x0268
> +#define USB_DEVICE_ID_SONY_PS4_CONTROLLER    0x05c4
> +#define USB_DEVICE_ID_SONY_PS4_CONTROLLER_2  0x09cc
> +#define USB_DEVICE_ID_SONY_PS4_CONTROLLER_DONGLE     0x0ba0
> +#define USB_DEVICE_ID_THQ_PS3_UDRAW  0xcb17
> +
> +/* List of devices blacklisted from joydev. A reason for blacklisting a
> + * device is to support (legacy) software supporting joydev, but which will
> + * never get updated to support these devices or features. An example would
> + * be handling of motion sensors, which these applications could not handle
> + * resulting in undefined behavior.
> + */
> +static const struct joydev_blacklist {
> +     __u16 bustype;
> +     __u16 vendor;
> +     __u16 product;
> +     unsigned long propbit; /* Allow for filtering based on device properties. */
> +} joydev_blacklist[] = {
> +     { BUS_BLUETOOTH, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS3_CONTROLLER, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_BLUETOOTH, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_BLUETOOTH, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER_2, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_USB, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS3_CONTROLLER, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_USB, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_USB, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER_2, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_USB, USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER_DONGLE, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { BUS_USB, USB_VENDOR_ID_THQ, USB_DEVICE_ID_THQ_PS3_UDRAW, BIT(INPUT_PROP_ACCELEROMETER) },
> +     { 0, 0, 0, 0}

I would assume that regardless of connection (USB, BT, SPI, I2C, the
accelerometer in PS4 controller should not be handled by joydev.  I
wonder if we should not factor out input device id matching from
input_match_device(), add propbit handling to input device id and use it
here? Then your blacklist would be:

#define ACCEL_DEV(vendor, product)                              \
        {                                                               \
                .flags          = INPUT_DEVICE_ID_MATCH_VENDOR |        \
                                        INPUT_DEVICE_ID_MATCH_PRODUCT | \
                                        INPUT_DEVICE_ID_MATCH_PROPBIT,  \
                .vendor         = (vendor),                             \
                .product        = (product),                            \
                .propbit[0]     = BIT(INPUT_PROP_ACCELEROMETER),        \
        }

static const struct input_device_id joydev_blacklist {
        ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS3_CONTROLLER),
        ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER),
        ...
        { }
};

> +};
> +
>  static int joydev_correct(int value, struct js_corr *corr)
>  {
>       switch (corr->type) {
> @@ -805,6 +839,25 @@ static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
>       return true;
>  }
>
> +
> +static bool joydev_dev_is_blacklisted(struct input_dev *dev)
> +{
> +     int i;
> +
> +     for (i = 0; joydev_blacklist[i].vendor; i++) {
> +             if (dev->id.bustype == joydev_blacklist[i].bustype &&
> +                 dev->id.vendor == joydev_blacklist[i].vendor &&
> +                 dev->id.product == joydev_blacklist[i].product &&
> +                 dev->propbit[0] == joydev_blacklist[i].propbit)

You probably want "&" and not strict match?

> +             {
> +                     dev_info(&dev->dev, "joydev: Blacklisting '%s'\n", dev->name);
> +                     return true;
> +             }
> +     }
> +
> +     return false;
> +}
> +
>  static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
>  {
>       /* Avoid touchpads and touchscreens */
> @@ -819,6 +872,10 @@ static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
>       if (joydev_dev_is_absolute_mouse(dev))
>               return false;
>
> +     /* Disable blacklisted devices */
> +     if (joydev_dev_is_blacklisted(dev))
> +             return false;
> +
>       return true;
>  }
>
> --
> 2.13.6
>

Thanks.

--
Dmitry