@@ -760,12 +760,31 @@ static int joycon_read_stick_calibration(struct joycon_ctlr *ctlr, u16 cal_addr,
cal_y->max = cal_y->center + y_max_above;
cal_y->min = cal_y->center - y_min_below;
- return 0;
+ /* check if values are plausible */
+ if (cal_x->min == cal_x->center || cal_x->center == cal_x->max ||
+ cal_y->min == cal_y->center || cal_y->center == cal_y->max)
+ ret = -EINVAL;
+
+ return ret;
}
static const u16 DFLT_STICK_CAL_CEN = 2000;
static const u16 DFLT_STICK_CAL_MAX = 3500;
static const u16 DFLT_STICK_CAL_MIN = 500;
+static void joycon_use_default_calibration(struct hid_device *hdev,
+ struct joycon_stick_cal *cal_x,
+ struct joycon_stick_cal *cal_y,
+ const char *stick, int ret)
+{
+ hid_warn(hdev,
+ "Failed to read %s stick cal, using defaults; e=%d\n", stick,
+ ret);
+
+ cal_x->center = cal_y->center = DFLT_STICK_CAL_CEN;
+ cal_x->max = cal_y->max = DFLT_STICK_CAL_MAX;
+ cal_x->min = cal_y->min = DFLT_STICK_CAL_MIN;
+}
+
static int joycon_request_calibration(struct joycon_ctlr *ctlr)
{
u16 left_stick_addr = JC_CAL_FCT_DATA_LEFT_ADDR;
@@ -793,38 +812,24 @@ static int joycon_request_calibration(struct joycon_ctlr *ctlr)
&ctlr->left_stick_cal_x,
&ctlr->left_stick_cal_y,
true);
- if (ret) {
- hid_warn(ctlr->hdev,
- "Failed to read left stick cal, using dflts; e=%d\n",
- ret);
-
- ctlr->left_stick_cal_x.center = DFLT_STICK_CAL_CEN;
- ctlr->left_stick_cal_x.max = DFLT_STICK_CAL_MAX;
- ctlr->left_stick_cal_x.min = DFLT_STICK_CAL_MIN;
- ctlr->left_stick_cal_y.center = DFLT_STICK_CAL_CEN;
- ctlr->left_stick_cal_y.max = DFLT_STICK_CAL_MAX;
- ctlr->left_stick_cal_y.min = DFLT_STICK_CAL_MIN;
- }
+ if (ret)
+ joycon_use_default_calibration(ctlr->hdev,
+ &ctlr->left_stick_cal_x,
+ &ctlr->left_stick_cal_y,
+ "left", ret);
/* read the right stick calibration data */
ret = joycon_read_stick_calibration(ctlr, right_stick_addr,
&ctlr->right_stick_cal_x,
&ctlr->right_stick_cal_y,
false);
- if (ret) {
- hid_warn(ctlr->hdev,
- "Failed to read right stick cal, using dflts; e=%d\n",
- ret);
-
- ctlr->right_stick_cal_x.center = DFLT_STICK_CAL_CEN;
- ctlr->right_stick_cal_x.max = DFLT_STICK_CAL_MAX;
- ctlr->right_stick_cal_x.min = DFLT_STICK_CAL_MIN;
- ctlr->right_stick_cal_y.center = DFLT_STICK_CAL_CEN;
- ctlr->right_stick_cal_y.max = DFLT_STICK_CAL_MAX;
- ctlr->right_stick_cal_y.min = DFLT_STICK_CAL_MIN;
- }
+ if (ret)
+ joycon_use_default_calibration(ctlr->hdev,
+ &ctlr->right_stick_cal_x,
+ &ctlr->right_stick_cal_y,
+ "right", ret);
hid_dbg(ctlr->hdev, "calibration:\n"
"l_x_c=%d l_x_max=%d l_x_min=%d\n"
Arne Wendt writes: Cheap clone controllers may (falsely) report as having a user calibration for the analog sticks in place, but return wrong/impossible values for the actual calibration data. In the present case at mine, the controller reports having a user calibration in place and successfully executes the read commands. The reported user calibration however is min = center = max = 0. This pull request addresses problems of this kind by checking the provided user calibration-data for plausibility (min < center < max) and falling back to the default values if implausible. I'll note that I was experiencing a crash because of this bug when using the GuliKit KingKong 2 controller. The crash manifests as a divide by zero error in the kernel logs: kernel: divide error: 0000 [#1] PREEMPT SMP NOPTI Changes in v2: - Move the plausibility check to joycon_read_stick_calibration() and have that function return -EINVAL if the check fails. - In the plausibility check, change >= to ==. hid_field_extract() never returns a negative value, so a scenario involving min > center or center > max is impossible. - To reduce code duplication, move the code for setting default calibration values into a single function called joycon_use_default_calibration(). Changes in v3: - Unbreak warning string to conform to coding style. - Change joycon_use_default_calibration() to accept a struct hid_device pointer instead of a struct joycon_ctlr pointer. Link: https://github.com/nicman23/dkms-hid-nintendo/pull/25 Link: https://github.com/DanielOgorchock/linux/issues/36 Co-authored-by: Arne Wendt <arne.wendt@tuhh.de> Signed-off-by: Johnothan King <johnothanking@protonmail.com> --- drivers/hid/hid-nintendo.c | 55 +++++++++++++++++++++----------------- 1 file changed, 30 insertions(+), 25 deletions(-)