Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Input: rotary_encoder - support binary encoding of states
It's not advisable to use this encoding, but to support existing devices
add support for this to the driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
authored by
Uwe Kleine-König
and committed by
Dmitry Torokhov
d205a218
f712a5a0
+26
-1
+4
Documentation/devicetree/bindings/input/rotary-encoder.txt
+4
Documentation/devicetree/bindings/input/rotary-encoder.txt
···
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2: Half-period mode
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4: Quarter-period mode
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- wakeup-source: Boolean, rotary encoder can wake up the system.
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- rotary-encoder,encoding: String, the method used to encode steps.
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Supported are "gray" (the default and more common) and "binary".
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Deprecated properties:
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- rotary-encoder,half-period: Makes the driver work on half-period mode.
···
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compatible = "rotary-encoder";
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gpios = <&gpio 19 1>, <&gpio 20 0>; /* GPIO19 is inverted */
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linux,axis = <0>; /* REL_X */
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rotary-encoder,encoding = "gray";
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rotary-encoder,relative-axis;
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};
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···
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gpios = <&gpio 21 0>, <&gpio 22 0>;
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linux,axis = <1>; /* ABS_Y */
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rotary-encoder,steps = <24>;
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rotary-encoder,encoding = "binary";
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rotary-encoder,rollover;
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};
+22
-1
drivers/input/misc/rotary_encoder.c
+22
-1
drivers/input/misc/rotary_encoder.c
···
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#define DRV_NAME "rotary-encoder"
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enum rotary_encoder_encoding {
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ROTENC_GRAY,
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ROTENC_BINARY,
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};
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struct rotary_encoder {
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struct input_dev *input;
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···
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u32 axis;
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bool relative_axis;
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bool rollover;
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enum rotary_encoder_encoding encoding;
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unsigned int pos;
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···
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for (i = 0; i < encoder->gpios->ndescs; ++i) {
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int val = gpiod_get_value_cansleep(encoder->gpios->desc[i]);
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/* convert from gray encoding to normal */
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-
if (ret & 1)
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if (encoder->encoding == ROTENC_GRAY && ret & 1)
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val = !val;
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ret = ret << 1 | val;
···
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encoder->rollover =
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device_property_read_bool(dev, "rotary-encoder,rollover");
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if (!device_property_present(dev, "rotary-encoder,encoding") ||
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!device_property_match_string(dev, "rotary-encoder,encoding",
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"gray")) {
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dev_info(dev, "gray");
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encoder->encoding = ROTENC_GRAY;
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} else if (!device_property_match_string(dev, "rotary-encoder,encoding",
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"binary")) {
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dev_info(dev, "binary");
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encoder->encoding = ROTENC_BINARY;
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} else {
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dev_err(dev, "unknown encoding setting\n");
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return -EINVAL;
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}
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device_property_read_u32(dev, "linux,axis", &encoder->axis);
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encoder->relative_axis =