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From:   Roderick Colenbrander <thunderbird2k@gmail.com>
Date:   Mon, 27 Jan 2020 14:07:43 -0800
Message-ID: <CAEc3jaDjVZF_Z7Guj1YUo5J5C_-GEOYTH=LKARKccCwQAwuZnQ@mail.gmail.com>
Subject: Re: [PATCH] HID: Sony: Add support for Gasia controllers
To:     Martyn Welch <martyn@welchs.me.uk>
Cc:     Jiri Kosina <jikos@kernel.org>,
        Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        linux-input <linux-input@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        "Conn O'Griofa" <connogriofa@gmail.com>,
        "Colenbrander, Roelof" <roderick.colenbrander@sony.com>
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Hi Martyn,

Thanks for sharing your patch. Though I must say with my Sony hat on,
I don't really like supporting clone devices (they hijack our device
ids.. etcetera) and we support hid-sony in an official capacity now
across various devices. Though thischange  all relates to PS3
generation, which is not that important anymore so it shouldn't matter
that much.

Thanks,
Roderick

On Sun, Jan 26, 2020 at 12:28 PM Martyn Welch <martyn@welchs.me.uk> wrote:
>
> There seems to be a number of subtly different firmwares for the
> Playstation controllers made by "Gasia Co.,Ltd". Whilst such controllers
> are easily detectable when attached via USB that is not always the case
> via Bluetooth. Some controllers are named "PLAYSTATION(R)3 Controller"
> where as the official Sony controllers are named
> "Sony PLAYSTATION(R)3 Controller", however some versions of firmware use
> the exact name used by the official controllers. The only way I've been
> able to distinguish these versions of the controller (when connected via
> Bluetooth) is that the Bluetooth Class of Device incorrectly reports the
> controller as a keyboard rather than a gamepad. I've so far failed to work
> out how to access this information from a HID driver.
>
> The Gasia controllers need output reports to be configured in the same way
> as the Shanwan controllers. In order to ensure both types of Gasia firmware
> will work, this patch adds a quirk for those devices it can detect and
> reworks `sixaxis_send_output_report()` to attempt `hid_hw_output_report()`
> should `hid_hw_raw_request()` be known to be the wrong option (as is the
> case with the Shanwan controllers) or fails.
>
> This has got all the controllers I have working, with the slight
> anoyance that the Gasia controllers that don't currently get marked with
> a quirk require the call to `hid_hw_raw_request()` to fail before the
> controller finishes initialising (which adds a significant extra delay
> before the controller is ready).
>
> This patch is based on the following patch by Conn O'Griofa:
>
> https://github.com/RetroPie/RetroPie-Setup/pull/2263/commits/017f00f6e15f04b3272ff1abae8742dc4c47b608
>
> Cc: Conn O'Griofa <connogriofa@gmail.com>
> Signed-off-by: Martyn Welch <martyn@welchs.me.uk>
> ---
>  drivers/hid/hid-sony.c | 31 +++++++++++++++++++++++++------
>  1 file changed, 25 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/hid/hid-sony.c b/drivers/hid/hid-sony.c
> index 4c6ed6ef31f1..d1088a85cb59 100644
> --- a/drivers/hid/hid-sony.c
> +++ b/drivers/hid/hid-sony.c
> @@ -56,6 +56,7 @@
>  #define NSG_MR5U_REMOTE_BT        BIT(14)
>  #define NSG_MR7U_REMOTE_BT        BIT(15)
>  #define SHANWAN_GAMEPAD           BIT(16)
> +#define GASIA_GAMEPAD             BIT(17)
>
>  #define SIXAXIS_CONTROLLER (SIXAXIS_CONTROLLER_USB | SIXAXIS_CONTROLLER_BT)
>  #define MOTION_CONTROLLER (MOTION_CONTROLLER_USB | MOTION_CONTROLLER_BT)
> @@ -2067,6 +2068,7 @@ static void sixaxis_send_output_report(struct sony_sc *sc)
>         struct sixaxis_output_report *report =
>                 (struct sixaxis_output_report *)sc->output_report_dmabuf;
>         int n;
> +       int ret = -1;
>
>         /* Initialize the report with default values */
>         memcpy(report, &default_report, sizeof(struct sixaxis_output_report));
> @@ -2101,14 +2103,23 @@ static void sixaxis_send_output_report(struct sony_sc *sc)
>                 }
>         }
>
> -       /* SHANWAN controllers require output reports via intr channel */
> -       if (sc->quirks & SHANWAN_GAMEPAD)
> -               hid_hw_output_report(sc->hdev, (u8 *)report,
> -                               sizeof(struct sixaxis_output_report));
> -       else
> -               hid_hw_raw_request(sc->hdev, report->report_id, (u8 *)report,
> +       /*
> +        * SHANWAN & GASIA controllers require output reports via intr channel.
> +        * Some of the Gasia controllers are basically indistinguishable from
> +        * the official ones and thus try hid_hw_output_report() should
> +        * hid_hw_raw_request() fail.
> +        */
> +       if (!(sc->quirks & (SHANWAN_GAMEPAD | GASIA_GAMEPAD)))
> +               ret = hid_hw_raw_request(sc->hdev, report->report_id,
> +                               (u8 *)report,
>                                 sizeof(struct sixaxis_output_report),
>                                 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
> +
> +       if (ret >= 0)
> +               return;

I don't like this pattern so much. We only need this "ret" check for
SHANWAN and GASIA. I would just do:

if (!(sc->quirks & (SHANWAN_GAMEPAD | GASIA_GAMEPAD))) {
    int ret = hid_hw_raw_request(....);
    if (ret >= 0)
       return;
}

hid_hw_output_report(....)

> +
> +       hid_hw_output_report(sc->hdev, (u8 *)report,
> +                       sizeof(struct sixaxis_output_report));
>  }
>
>  static void dualshock4_send_output_report(struct sony_sc *sc)
> @@ -2833,6 +2844,14 @@ static int sony_probe(struct hid_device *hdev, const struct hid_device_id *id)
>         if (!strcmp(hdev->name, "SHANWAN PS3 GamePad"))
>                 quirks |= SHANWAN_GAMEPAD;
>
> +       /*
> +        * Some Gasia controllers are named "PLAYSTATION(R)3 Controller"
> +        * where as the official Sony controllers are named
> +        * "Sony PLAYSTATION(R)3 Controller".
> +        */
> +       if (!strcmp(hdev->name, "PLAYSTATION(R)3 Controller"))
> +               quirks |= GASIA_GAMEPAD;
> +
>         sc = devm_kzalloc(&hdev->dev, sizeof(*sc), GFP_KERNEL);
>         if (sc == NULL) {
>                 hid_err(hdev, "can't alloc sony descriptor\n");
> --
> 2.20.1
>