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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-24 11:58:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-24 11:58:49 -0700
commit4637f40f200063973553ce3c4c1ac6c247e4535c (patch)
treeff317a0dfb67cae313a208d120edd5102730044d /drivers/input/misc/rotary_encoder.c
parent5129df03d0c44b2d5a5f9d7d52f3b079706b9a8f (diff)
parentb73077eb03f510a84b102fb97640e595a958403c (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (40 commits) Input: ADP5589 - new driver for I2C Keypad Decoder and I/O Expander Input: tsc2007 - add X, Y and Z fuzz factors to platform data Input: tsc2007 - add poll_period parameter to platform data Input: tsc2007 - add poll_delay parameter to platform data Input: tsc2007 - add max_rt parameter to platform data Input: tsc2007 - debounce pressure measurement Input: ad714x - fix captouch wheel option algorithm Input: ad714x - allow platform code to specify irqflags Input: ad714x - fix threshold and completion interrupt masks Input: ad714x - fix up input configuration Input: elantech - remove support for proprietary X driver Input: elantech - report multitouch with proper ABS_MT messages Input: elantech - export pressure and width when supported Input: elantech - describe further the protocol Input: atmel_tsadcc - correct call to input_free_device Input: add driver FSL MPR121 capacitive touch sensor Input: remove useless synchronize_rcu() calls Input: ads7846 - fix gpio_pendown configuration Input: ads7846 - add possibility to use external vref on ads7846 Input: rotary-encoder - add support for half-period encoders ...
Diffstat (limited to 'drivers/input/misc/rotary_encoder.c')
-rw-r--r--drivers/input/misc/rotary_encoder.c119
1 files changed, 83 insertions, 36 deletions
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 7e64d01da2be..2c8b84dd9dac 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -2,6 +2,7 @@
* rotary_encoder.c
*
* (c) 2009 Daniel Mack <daniel@caiaq.de>
+ * Copyright (C) 2011 Johan Hovold <jhovold@gmail.com>
*
* state machine code inspired by code from Tim Ruetz
*
@@ -38,52 +39,66 @@ struct rotary_encoder {
bool armed;
unsigned char dir; /* 0 - clockwise, 1 - CCW */
+
+ char last_stable;
};
-static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
+static int rotary_encoder_get_state(struct rotary_encoder_platform_data *pdata)
{
- struct rotary_encoder *encoder = dev_id;
- struct rotary_encoder_platform_data *pdata = encoder->pdata;
int a = !!gpio_get_value(pdata->gpio_a);
int b = !!gpio_get_value(pdata->gpio_b);
- int state;
a ^= pdata->inverted_a;
b ^= pdata->inverted_b;
- state = (a << 1) | b;
- switch (state) {
+ return ((a << 1) | b);
+}
- case 0x0:
- if (!encoder->armed)
- break;
+static void rotary_encoder_report_event(struct rotary_encoder *encoder)
+{
+ struct rotary_encoder_platform_data *pdata = encoder->pdata;
- if (pdata->relative_axis) {
- input_report_rel(encoder->input, pdata->axis,
- encoder->dir ? -1 : 1);
- } else {
- unsigned int pos = encoder->pos;
-
- if (encoder->dir) {
- /* turning counter-clockwise */
- if (pdata->rollover)
- pos += pdata->steps;
- if (pos)
- pos--;
- } else {
- /* turning clockwise */
- if (pdata->rollover || pos < pdata->steps)
- pos++;
- }
+ if (pdata->relative_axis) {
+ input_report_rel(encoder->input,
+ pdata->axis, encoder->dir ? -1 : 1);
+ } else {
+ unsigned int pos = encoder->pos;
+
+ if (encoder->dir) {
+ /* turning counter-clockwise */
if (pdata->rollover)
- pos %= pdata->steps;
- encoder->pos = pos;
- input_report_abs(encoder->input, pdata->axis,
- encoder->pos);
+ pos += pdata->steps;
+ if (pos)
+ pos--;
+ } else {
+ /* turning clockwise */
+ if (pdata->rollover || pos < pdata->steps)
+ pos++;
}
- input_sync(encoder->input);
- encoder->armed = false;
+ if (pdata->rollover)
+ pos %= pdata->steps;
+
+ encoder->pos = pos;
+ input_report_abs(encoder->input, pdata->axis, encoder->pos);
+ }
+
+ input_sync(encoder->input);
+}
+
+static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
+{
+ struct rotary_encoder *encoder = dev_id;
+ int state;
+
+ state = rotary_encoder_get_state(encoder->pdata);
+
+ switch (state) {
+ case 0x0:
+ if (encoder->armed) {
+ rotary_encoder_report_event(encoder);
+ encoder->armed = false;
+ }
break;
case 0x1:
@@ -100,11 +115,37 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
return IRQ_HANDLED;
}
+static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
+{
+ struct rotary_encoder *encoder = dev_id;
+ int state;
+
+ state = rotary_encoder_get_state(encoder->pdata);
+
+ switch (state) {
+ case 0x00:
+ case 0x03:
+ if (state != encoder->last_stable) {
+ rotary_encoder_report_event(encoder);
+ encoder->last_stable = state;
+ }
+ break;
+
+ case 0x01:
+ case 0x02:
+ encoder->dir = (encoder->last_stable + state) & 0x01;
+ break;
+ }
+
+ return IRQ_HANDLED;
+}
+
static int __devinit rotary_encoder_probe(struct platform_device *pdev)
{
struct rotary_encoder_platform_data *pdata = pdev->dev.platform_data;
struct rotary_encoder *encoder;
struct input_dev *input;
+ irq_handler_t handler;
int err;
if (!pdata) {
@@ -175,7 +216,14 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
}
/* request the IRQs */
- err = request_irq(encoder->irq_a, &rotary_encoder_irq,
+ if (pdata->half_period) {
+ handler = &rotary_encoder_half_period_irq;
+ encoder->last_stable = rotary_encoder_get_state(pdata);
+ } else {
+ handler = &rotary_encoder_irq;
+ }
+
+ err = request_irq(encoder->irq_a, handler,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
DRV_NAME, encoder);
if (err) {
@@ -184,7 +232,7 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
goto exit_free_gpio_b;
}
- err = request_irq(encoder->irq_b, &rotary_encoder_irq,
+ err = request_irq(encoder->irq_b, handler,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
DRV_NAME, encoder);
if (err) {
@@ -252,6 +300,5 @@ module_exit(rotary_encoder_exit);
MODULE_ALIAS("platform:" DRV_NAME);
MODULE_DESCRIPTION("GPIO rotary encoder driver");
-MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>, Johan Hovold");
MODULE_LICENSE("GPL v2");
-