[PATCH 1/2] drivers: hid: adjust gyro calibration data

From: Henry Castro
Date: Thu Oct 06 2022 - 09:36:35 EST


For some reason my DualShock 4 get the calibration
data values equal:

gyro_pitch_plus == gyro_pitch_minus

Probably due to some defect in the DS4 hardware, and cause
a CPU division exception to crash the linux kernel.

At least with the patch, I can continue play Retroarch
without using the Gyroscope :)

Signed-off-by: Henry Castro <hcvcastro@xxxxxxxxx>
---

>> Hm, I'm not the biggest fan. Is this an official DS4 or a clone
>> device? It sounds like it is some type of clone (some look real).

Sorry it happens in my DS4 clone:

I have the log values:

gyro_pitch_plus = 8704
giro_pitch_minus = 8704

Then the division exception:

mult_frac(x, y, 0)



drivers/hid/hid-sony.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/hid/hid-sony.c b/drivers/hid/hid-sony.c
index 87b538656f64..656caa07b25f 100644
--- a/drivers/hid/hid-sony.c
+++ b/drivers/hid/hid-sony.c
@@ -1823,6 +1823,15 @@ static int dualshock4_get_calibration_data(struct sony_sc *sc)
acc_z_plus = get_unaligned_le16(&buf[31]);
acc_z_minus = get_unaligned_le16(&buf[33]);

+ if (gyro_pitch_plus == gyro_pitch_minus)
+ gyro_pitch_minus *= -1;
+
+ if (gyro_yaw_plus == gyro_yaw_minus)
+ gyro_yaw_minus *= -1;
+
+ if (gyro_roll_plus == gyro_roll_minus)
+ gyro_roll_minus *= -1;
+
/* Set gyroscope calibration and normalization parameters.
* Data values will be normalized to 1/DS4_GYRO_RES_PER_DEG_S degree/s.
*/
--
2.20.1