From 6560cfcfb46511d47893d6e3994ce1d3c58ddf7f Mon Sep 17 00:00:00 2001 From: Chris Morgan Date: Fri, 19 Jan 2024 00:19:08 -0800 Subject: [PATCH] Input: adc-joystick - handle inverted axes When one or more axes are inverted, (where min > max), normalize the data so that min < max and invert the values reported to the input stack. This ensures we can continue defining the device correctly in the device tree while not breaking downstream assumptions that min is always less than max. Signed-off-by: Chris Morgan Acked-by: Artur Rojek Link: https://lore.kernel.org/r/20240115192752.266367-1-macroalpha82@gmail.com Signed-off-by: Dmitry Torokhov --- drivers/input/joystick/adc-joystick.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c index c0deff5d4282..916e78e4dc9f 100644 --- a/drivers/input/joystick/adc-joystick.c +++ b/drivers/input/joystick/adc-joystick.c @@ -18,6 +18,7 @@ struct adc_joystick_axis { s32 range[2]; s32 fuzz; s32 flat; + bool inverted; }; struct adc_joystick { @@ -29,6 +30,15 @@ struct adc_joystick { bool polled; }; +static int adc_joystick_invert(struct input_dev *dev, + unsigned int axis, int val) +{ + int min = input_abs_get_min(dev, axis); + int max = input_abs_get_max(dev, axis); + + return (max + min) - val; +} + static void adc_joystick_poll(struct input_dev *input) { struct adc_joystick *joy = input_get_drvdata(input); @@ -38,6 +48,8 @@ static void adc_joystick_poll(struct input_dev *input) ret = iio_read_channel_raw(&joy->chans[i], &val); if (ret < 0) return; + if (joy->axes[i].inverted) + val = adc_joystick_invert(input, i, val); input_report_abs(input, joy->axes[i].code, val); } input_sync(input); @@ -86,6 +98,8 @@ static int adc_joystick_handle(const void *data, void *private) val = sign_extend32(val, msb); else val &= GENMASK(msb, 0); + if (joy->axes[i].inverted) + val = adc_joystick_invert(joy->input, i, val); input_report_abs(joy->input, joy->axes[i].code, val); } @@ -168,6 +182,12 @@ static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) goto err_fwnode_put; } + if (axes[i].range[0] > axes[i].range[1]) { + dev_dbg(dev, "abs-axis %d inverted\n", i); + axes[i].inverted = true; + swap(axes[i].range[0], axes[i].range[1]); + } + fwnode_property_read_u32(child, "abs-fuzz", &axes[i].fuzz); fwnode_property_read_u32(child, "abs-flat", &axes[i].flat);