Re: [PATCH 5/7] Input: xpad: disconnect all Wireless controllers at init

["Pierre-Loup A. Griffais" <pgriffais@valvesoftware.com>]

There's apparently a packet you can send to the receiver that prompts it 
to immediately send feedback about all the paired controllers that would 
be ideal as a replacement for this kludge. I will test it and send out a 
replacement patch for 5/7 in that series if it turns out to work well. 
Thanks a lot to Zachary Lund for pointing this out.

On 01/31/2014 05:03 AM, Greg Kroah-Hartman wrote:
> From: "Pierre-Loup A. Griffais" <pgriffais@valvesoftware.com>
>
> We initializing the driver/device, we really don't know how many
> controllers are connected.  So send a "disconnect all" command to the
> base-station, and let the user pair the controllers in the order in
> which they want them assigned.
>
> Note, this means we now do not "preallocate" all 4 devices when a single
> wireless base station is seen, but require the device to be properly
> connected to the base station before that can happen.  The allocation of
> the device happens in the next patch, not here, so in a way, this patch
> breaks all wireless devices...
>
> Because we want to talk to the device, we have to set up the output urbs
> no matter if we have CONFIG_JOYSTICK_XPAD_FF or
> CONFIG_JOYSTICK_XPAD_LEDS enabled not, so take out the code that allows
> those variables and code to be disabled (it's so small it should never
> matter...)
>
> Signed-off-by: "Pierre-Loup A. Griffais" <pgriffais@valvesoftware.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>   drivers/input/joystick/xpad.c | 46 ++++++++++++++++++++++++++++++++-----------
>   1 file changed, 34 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/input/joystick/xpad.c b/drivers/input/joystick/xpad.c
> index 7997ae89a877..7a07b95790d7 100644
> --- a/drivers/input/joystick/xpad.c
> +++ b/drivers/input/joystick/xpad.c
> @@ -278,12 +278,10 @@ struct usb_xpad {
>   	struct urb *bulk_out;
>   	unsigned char *bdata;
>
> -#if defined(CONFIG_JOYSTICK_XPAD_FF) || defined(CONFIG_JOYSTICK_XPAD_LEDS)
>   	struct urb *irq_out;		/* urb for interrupt out report */
>   	unsigned char *odata;		/* output data */
>   	dma_addr_t odata_dma;
>   	struct mutex odata_mutex;
> -#endif
>
>   #if defined(CONFIG_JOYSTICK_XPAD_LEDS)
>   	struct xpad_led *led;
> @@ -537,7 +535,6 @@ static void xpad_bulk_out(struct urb *urb)
>   	}
>   }
>
> -#if defined(CONFIG_JOYSTICK_XPAD_FF) || defined(CONFIG_JOYSTICK_XPAD_LEDS)
>   static void xpad_irq_out(struct urb *urb)
>   {
>   	struct usb_xpad *xpad = urb->context;
> @@ -623,11 +620,6 @@ static void xpad_deinit_output(struct usb_xpad *xpad)
>   				xpad->odata, xpad->odata_dma);
>   	}
>   }
> -#else
> -static int xpad_init_output(struct usb_interface *intf, struct usb_xpad *xpad) { return 0; }
> -static void xpad_deinit_output(struct usb_xpad *xpad) {}
> -static void xpad_stop_output(struct usb_xpad *xpad) {}
> -#endif
>
>   #ifdef CONFIG_JOYSTICK_XPAD_FF
>   static int xpad_play_effect(struct input_dev *dev, void *data, struct ff_effect *effect)
> @@ -1091,11 +1083,41 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
>   			usb_kill_urb(xpad->irq_in);
>   			goto fail9;
>   		}
> +
> +		/*
> +		 * We don't know how to check the controller state at driver
> +		 * load, so just disconnect them all, requiring the user to
> +		 * repair the device in the order they want them used.  Good
> +		 * point is that we don't connect devices in "random" order,
> +		 * but the extra step seems a bit harsh as other operating
> +		 * systems don't require this at the moment.
> +		 *
> +		 * Power-off packet information came from an OS-X
> +		 * reverse-engineered driver located at:
> +		 * http://tattiebogle.net/index.php/ProjectRoot/Xbox360Controller/OsxDriver#toc1
> +		 */
> +		mutex_lock(&xpad->odata_mutex);
> +		xpad->odata[0] = 0x00;
> +		xpad->odata[1] = 0x00;
> +		xpad->odata[2] = 0x08;
> +		xpad->odata[3] = 0xC0;
> +		xpad->odata[4] = 0x00;
> +		xpad->odata[5] = 0x00;
> +		xpad->odata[6] = 0x00;
> +		xpad->odata[7] = 0x00;
> +		xpad->odata[8] = 0x00;
> +		xpad->odata[9] = 0x00;
> +		xpad->odata[10] = 0x00;
> +		xpad->odata[11] = 0x00;
> +		xpad->irq_out->transfer_buffer_length = 12;
> +		usb_submit_urb(xpad->irq_out, GFP_KERNEL);
> +		mutex_unlock(&xpad->odata_mutex);
> +	} else {
> +		xpad->pad_present = 1;
> +		error = xpad_init_input(xpad);
> +		if (error)
> +			goto fail9;
>   	}
> -	xpad->pad_present = 1;
> -	error = xpad_init_input(xpad);
> -	if (error)
> -		goto fail9;
>
>   	return 0;
>
>