For detachable or lock-able joysticks the ADC lanes might be biased to GND or AVDD when the joystick is detached/locked. One such kind of joystick is found in the Ritmix RZX-50 device. The joystick is non-detachable, although ADC lane biased to power supply when the "Hold" switch is activated. To avoid reporting old/broken measurements valid-range is used. When measured value is outside valid-range the driver reports safe center position for corresponding axis. Signed-off-by: Siarhei Volkau <lis8215@xxxxxxxxx> --- drivers/input/joystick/adc-joystick.c | 58 ++++++++++++++++++++++++++- 1 file changed, 57 insertions(+), 1 deletion(-) diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c index c0deff5d4..6a143dc38 100644 --- a/drivers/input/joystick/adc-joystick.c +++ b/drivers/input/joystick/adc-joystick.c @@ -18,6 +18,8 @@ struct adc_joystick_axis { s32 range[2]; s32 fuzz; s32 flat; + s32 valid[2]; + s32 center; }; struct adc_joystick { @@ -29,6 +31,14 @@ struct adc_joystick { bool polled; }; +static inline bool is_in_range(const s32 *range, int val) +{ + s32 min = range[0]; + s32 max = range[1]; + + return (min == 0 && max == 0) || (val >= min && val <= max); +} + static void adc_joystick_poll(struct input_dev *input) { struct adc_joystick *joy = input_get_drvdata(input); @@ -38,6 +48,10 @@ static void adc_joystick_poll(struct input_dev *input) ret = iio_read_channel_raw(&joy->chans[i], &val); if (ret < 0) return; + + if (!is_in_range(joy->axes[i].valid, val)) + val = joy->axes[i].center; + input_report_abs(input, joy->axes[i].code, val); } input_sync(input); @@ -86,6 +100,10 @@ static int adc_joystick_handle(const void *data, void *private) val = sign_extend32(val, msb); else val &= GENMASK(msb, 0); + + if (!is_in_range(joy->axes[i].valid, val)) + val = joy->axes[i].center; + input_report_abs(joy->input, joy->axes[i].code, val); } @@ -119,6 +137,21 @@ static void adc_joystick_cleanup(void *data) iio_channel_release_all_cb(data); } +static bool valid_range_covers_abs_range(struct adc_joystick_axis *axis) +{ + s32 abs_min, abs_max; + + if (axis->range[0] > axis->range[1]) { + abs_min = axis->range[1]; + abs_max = axis->range[0]; + } else { + abs_min = axis->range[0]; + abs_max = axis->range[1]; + } + + return axis->valid[0] <= abs_min && axis->valid[1] >= abs_max; +} + static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) { struct adc_joystick_axis *axes; @@ -137,7 +170,7 @@ static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) return -EINVAL; } - axes = devm_kmalloc_array(dev, num_axes, sizeof(*axes), GFP_KERNEL); + axes = devm_kcalloc(dev, num_axes, sizeof(*axes), GFP_KERNEL); if (!axes) return -ENOMEM; @@ -167,10 +200,33 @@ static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) dev_err(dev, "abs-range invalid or missing\n"); goto err_fwnode_put; } + axes[i].center = (axes[i].range[0] + axes[i].range[1]) / 2; fwnode_property_read_u32(child, "abs-fuzz", &axes[i].fuzz); fwnode_property_read_u32(child, "abs-flat", &axes[i].flat); + if (fwnode_property_present(child, "valid-range")) { + error = fwnode_property_read_u32_array(child, + "valid-range", + axes[i].valid, 2); + if (error) { + dev_err(dev, "valid-range invalid\n"); + goto err_fwnode_put; + } + + if (axes[i].valid[0] > axes[i].valid[1]) { + dev_err(dev, + "valid-range invalid (min > max)\n"); + goto err_fwnode_put; + } + + if (!valid_range_covers_abs_range(&axes[i])) { + dev_err(dev, + "valid-range must cover abs-range\n"); + goto err_fwnode_put; + } + } + input_set_abs_params(joy->input, axes[i].code, axes[i].range[0], axes[i].range[1], axes[i].fuzz, axes[i].flat); -- 2.36.1