From: Johnothan King <johnothanking@xxxxxxxxxxxxxx> [ Upstream commit 50503e360eeb968a3d00234c9cc4057d774c3e9a ] 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 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@xxxxxxx> Signed-off-by: Johnothan King <johnothanking@xxxxxxxxxxxxxx> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> Link: https://lore.kernel.org/r/gvpL2G6VwXGJPvxX5KRiu9pVjvTivgayug_jdKDY6zfuAaAqncP9BkKLosjwUXNlgVVTMfJSKfwPF1K79cKAkwGComyC21vCV3q9B3EXNkE=@protonmail.com Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/hid/hid-nintendo.c | 55 +++++++++++++++++++++----------------- 1 file changed, 30 insertions(+), 25 deletions(-) diff --git a/drivers/hid/hid-nintendo.c b/drivers/hid/hid-nintendo.c index 6028af3c3aae..c3774a468b22 100644 --- a/drivers/hid/hid-nintendo.c +++ b/drivers/hid/hid-nintendo.c @@ -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 calibration 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" -- 2.35.1
