Commit c70e67590049380875d018b1f29f181837594dbf
2022-11-03T12:37:54
Wait a bit for devices to initialize before trying to enumerate and open them. This works around udev event nodes arriving before hidraw nodes and the controller being opened twice - once using the Linux driver and once by the HIDAPI driver. This also fixes a kernel panic on Steam Link hardware due to trying to open the hidraw device node too early. A delay of 10 ms seems to be a good value, tested on Steam Link hardware.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52
diff --git a/src/joystick/hidapi/SDL_hidapijoystick.c b/src/joystick/hidapi/SDL_hidapijoystick.c
index aab90ed..2ed4aee 100644
--- a/src/joystick/hidapi/SDL_hidapijoystick.c
+++ b/src/joystick/hidapi/SDL_hidapijoystick.c
@@ -368,26 +368,22 @@ HIDAPI_SetupDeviceDriver(SDL_HIDAPI_Device *device, SDL_bool *removed)
*
* See https://github.com/libsdl-org/SDL/issues/6347 for details
*/
- const int MAX_ATTEMPTS = 3;
- int attempt;
int lock_count = 0;
SDL_HIDAPI_Device *curr;
SDL_hid_device *dev;
char *path = SDL_strdup(device->path);
+ /* Wait a little bit for the device to initialize */
+ SDL_Delay(10);
+
SDL_AssertJoysticksLocked();
while (SDL_JoysticksLocked()) {
++lock_count;
SDL_UnlockJoysticks();
}
- for (attempt = 0; attempt < MAX_ATTEMPTS; ++attempt) {
- dev = SDL_hid_open_path(path, 0);
- if (dev != NULL) {
- break;
- }
- /* Wait a bit and try again */
- SDL_Delay(30);
- }
+
+ dev = SDL_hid_open_path(path, 0);
+
while (lock_count > 0) {
--lock_count;
SDL_LockJoysticks();
diff --git a/src/joystick/linux/SDL_sysjoystick.c b/src/joystick/linux/SDL_sysjoystick.c
index 4e3da5d..5d3a994 100644
--- a/src/joystick/linux/SDL_sysjoystick.c
+++ b/src/joystick/linux/SDL_sysjoystick.c
@@ -267,6 +267,10 @@ static void joystick_udev_callback(SDL_UDEV_deviceevent udev_type, int udev_clas
return;
}
}
+
+ /* Wait a bit for the hidraw udev node to initialize */
+ SDL_Delay(10);
+
MaybeAddDevice(devpath);
break;