HID: usbhid: extend polling interval configuration to joysticks

For mouse devices we can currently change the polling interval
via usbhid.mousepoll. Implement the same thing for joysticks, so
users can reduce input latency this way.

This has been tested with a Logitech RumblePad 2 with jspoll=2,
resulting in a polling rate of 500Hz (verified with evhz).

Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 520af84e0b070d8f9957f4276f6da2ed681898ab..34ecbca8a5bcea5b4cb454ace1c0517fc31feedf 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -4330,6 +4330,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
        usbhid.mousepoll=
                        [USBHID] The interval which mice are to be polled at.
 
+       usbhid.jspoll=
+                       [USBHID] The interval which joysticks are to be polled at.
+
        usb-storage.delay_use=
                        [UMS] The delay in seconds before a new device is
                        scanned for Logical Units (default 1).

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 7838343eb37c541d698a7e78ff265e789fda7c98..22a955c5cc7e2ac83362c2bdc1a247b4776c9c08 100644 (file)
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -53,6 +53,10 @@ static unsigned int hid_mousepoll_interval;
 module_param_named(mousepoll, hid_mousepoll_interval, uint, 0644);
 MODULE_PARM_DESC(mousepoll, "Polling interval of mice");
 
+static unsigned int hid_jspoll_interval;
+module_param_named(jspoll, hid_jspoll_interval, uint, 0644);
+MODULE_PARM_DESC(jspoll, "Polling interval of joysticks");
+
 static unsigned int ignoreled;
 module_param_named(ignoreled, ignoreled, uint, 0644);
 MODULE_PARM_DESC(ignoreled, "Autosuspend with active leds");
@@ -1092,9 +1096,17 @@ static int usbhid_start(struct hid_device *hid)
                               hid->name, endpoint->bInterval, interval);
                }
 
-               /* Change the polling interval of mice. */
-               if (hid->collection->usage == HID_GD_MOUSE && hid_mousepoll_interval > 0)
-                       interval = hid_mousepoll_interval;
+               /* Change the polling interval of mice and joysticks. */
+               switch (hid->collection->usage) {
+               case HID_GD_MOUSE:
+                       if (hid_mousepoll_interval > 0)
+                               interval = hid_mousepoll_interval;
+                       break;
+               case HID_GD_JOYSTICK:
+                       if (hid_jspoll_interval > 0)
+                               interval = hid_jspoll_interval;
+                       break;
+               }
 
                ret = -ENOMEM;
                if (usb_endpoint_dir_in(endpoint)) {