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-rw-r--r--Documentation/devicetree/bindings/input/rotary-encoder.txt2
-rw-r--r--drivers/input/misc/rotary_encoder.c156
2 files changed, 65 insertions, 93 deletions
diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
index de99cbbbf6da..6c9f0c8a846c 100644
--- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
+++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
@@ -1,7 +1,7 @@
Rotary encoder DT bindings
Required properties:
-- gpios: a spec for two GPIOs to be used
+- gpios: a spec for at least two GPIOs to be used, most significant first
Optional properties:
- linux,axis: the input subsystem axis to map to this rotary encoder.
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 5a4e1d69c4af..96c486de49e0 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -40,35 +40,42 @@ struct rotary_encoder {
unsigned int pos;
- struct gpio_desc *gpio_a;
- struct gpio_desc *gpio_b;
+ struct gpio_descs *gpios;
- unsigned int irq_a;
- unsigned int irq_b;
+ unsigned int *irq;
bool armed;
- unsigned char dir; /* 0 - clockwise, 1 - CCW */
+ signed char dir; /* 1 - clockwise, -1 - CCW */
- char last_stable;
+ unsigned last_stable;
};
-static int rotary_encoder_get_state(struct rotary_encoder *encoder)
+static unsigned rotary_encoder_get_state(struct rotary_encoder *encoder)
{
- int a = !!gpiod_get_value_cansleep(encoder->gpio_a);
- int b = !!gpiod_get_value_cansleep(encoder->gpio_b);
+ int i;
+ unsigned ret = 0;
- return ((a << 1) | b);
+ for (i = 0; i < encoder->gpios->ndescs; ++i) {
+ int val = gpiod_get_value_cansleep(encoder->gpios->desc[i]);
+ /* convert from gray encoding to normal */
+ if (ret & 1)
+ val = !val;
+
+ ret = ret << 1 | val;
+ }
+
+ return ret & 3;
}
static void rotary_encoder_report_event(struct rotary_encoder *encoder)
{
if (encoder->relative_axis) {
input_report_rel(encoder->input,
- encoder->axis, encoder->dir ? -1 : 1);
+ encoder->axis, encoder->dir);
} else {
unsigned int pos = encoder->pos;
- if (encoder->dir) {
+ if (encoder->dir < 0) {
/* turning counter-clockwise */
if (encoder->rollover)
pos += encoder->steps;
@@ -93,7 +100,7 @@ static void rotary_encoder_report_event(struct rotary_encoder *encoder)
static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
{
struct rotary_encoder *encoder = dev_id;
- int state;
+ unsigned state;
mutex_lock(&encoder->access_mutex);
@@ -108,12 +115,12 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
break;
case 0x1:
- case 0x2:
+ case 0x3:
if (encoder->armed)
- encoder->dir = state - 1;
+ encoder->dir = 2 - state;
break;
- case 0x3:
+ case 0x2:
encoder->armed = true;
break;
}
@@ -126,25 +133,19 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
{
struct rotary_encoder *encoder = dev_id;
- int state;
+ unsigned int state;
mutex_lock(&encoder->access_mutex);
state = rotary_encoder_get_state(encoder);
- switch (state) {
- case 0x00:
- case 0x03:
+ if (state & 1) {
+ encoder->dir = ((encoder->last_stable - state + 1) % 4) - 1;
+ } else {
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;
}
mutex_unlock(&encoder->access_mutex);
@@ -155,46 +156,18 @@ static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
static irqreturn_t rotary_encoder_quarter_period_irq(int irq, void *dev_id)
{
struct rotary_encoder *encoder = dev_id;
- unsigned char sum;
- int state;
+ unsigned int state;
mutex_lock(&encoder->access_mutex);
state = rotary_encoder_get_state(encoder);
- /*
- * We encode the previous and the current state using a byte.
- * The previous state in the MSB nibble, the current state in the LSB
- * nibble. Then use a table to decide the direction of the turn.
- */
- sum = (encoder->last_stable << 4) + state;
- switch (sum) {
- case 0x31:
- case 0x10:
- case 0x02:
- case 0x23:
- encoder->dir = 0; /* clockwise */
- break;
-
- case 0x13:
- case 0x01:
- case 0x20:
- case 0x32:
- encoder->dir = 1; /* counter-clockwise */
- break;
-
- default:
- /*
- * Ignore all other values. This covers the case when the
- * state didn't change (a spurious interrupt) and the
- * cases where the state changed by two steps, making it
- * impossible to tell the direction.
- *
- * In either case, don't report any event and save the
- * state for later.
- */
+ if ((encoder->last_stable + 1) % 4 == state)
+ encoder->dir = 1;
+ else if (encoder->last_stable == (state + 1) % 4)
+ encoder->dir = -1;
+ else
goto out;
- }
rotary_encoder_report_event(encoder);
@@ -212,6 +185,7 @@ static int rotary_encoder_probe(struct platform_device *pdev)
struct input_dev *input;
irq_handler_t handler;
u32 steps_per_period;
+ unsigned int i;
int err;
encoder = devm_kzalloc(dev, sizeof(struct rotary_encoder), GFP_KERNEL);
@@ -243,24 +217,16 @@ static int rotary_encoder_probe(struct platform_device *pdev)
encoder->relative_axis =
device_property_read_bool(dev, "rotary-encoder,relative-axis");
- encoder->gpio_a = devm_gpiod_get_index(dev, NULL, 0, GPIOD_IN);
- if (IS_ERR(encoder->gpio_a)) {
- err = PTR_ERR(encoder->gpio_a);
- dev_err(dev, "unable to get GPIO at index 0: %d\n", err);
- return err;
+ encoder->gpios = devm_gpiod_get_array(dev, NULL, GPIOD_IN);
+ if (IS_ERR(encoder->gpios)) {
+ dev_err(dev, "unable to get gpios\n");
+ return PTR_ERR(encoder->gpios);
}
-
- encoder->irq_a = gpiod_to_irq(encoder->gpio_a);
-
- encoder->gpio_b = devm_gpiod_get_index(dev, NULL, 1, GPIOD_IN);
- if (IS_ERR(encoder->gpio_b)) {
- err = PTR_ERR(encoder->gpio_b);
- dev_err(dev, "unable to get GPIO at index 1: %d\n", err);
- return err;
+ if (encoder->gpios->ndescs < 2) {
+ dev_err(dev, "not enough gpios found\n");
+ return -EINVAL;
}
- encoder->irq_b = gpiod_to_irq(encoder->gpio_b);
-
input = devm_input_allocate_device(dev);
if (!input)
return -ENOMEM;
@@ -277,7 +243,7 @@ static int rotary_encoder_probe(struct platform_device *pdev)
input_set_abs_params(input,
encoder->axis, 0, encoder->steps, 0, 1);
- switch (steps_per_period) {
+ switch (steps_per_period >> (encoder->gpios->ndescs - 2)) {
case 4:
handler = &rotary_encoder_quarter_period_irq;
encoder->last_stable = rotary_encoder_get_state(encoder);
@@ -295,22 +261,26 @@ static int rotary_encoder_probe(struct platform_device *pdev)
return -EINVAL;
}
- err = devm_request_threaded_irq(dev, encoder->irq_a, NULL, handler,
- IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
- IRQF_ONESHOT,
- DRV_NAME, encoder);
- if (err) {
- dev_err(dev, "unable to request IRQ %d\n", encoder->irq_a);
- return err;
- }
+ encoder->irq =
+ devm_kzalloc(dev,
+ sizeof(*encoder->irq) * encoder->gpios->ndescs,
+ GFP_KERNEL);
+ if (!encoder->irq)
+ return -ENOMEM;
- err = devm_request_threaded_irq(dev, encoder->irq_b, NULL, handler,
+ for (i = 0; i < encoder->gpios->ndescs; ++i) {
+ encoder->irq[i] = gpiod_to_irq(encoder->gpios->desc[i]);
+
+ err = devm_request_threaded_irq(dev, encoder->irq[i],
+ NULL, handler,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
DRV_NAME, encoder);
- if (err) {
- dev_err(dev, "unable to request IRQ %d\n", encoder->irq_b);
- return err;
+ if (err) {
+ dev_err(dev, "unable to request IRQ %d (gpio#%d)\n",
+ encoder->irq[i], i);
+ return err;
+ }
}
err = input_register_device(input);
@@ -330,10 +300,11 @@ static int rotary_encoder_probe(struct platform_device *pdev)
static int __maybe_unused rotary_encoder_suspend(struct device *dev)
{
struct rotary_encoder *encoder = dev_get_drvdata(dev);
+ unsigned int i;
if (device_may_wakeup(dev)) {
- enable_irq_wake(encoder->irq_a);
- enable_irq_wake(encoder->irq_b);
+ for (i = 0; i < encoder->gpios->ndescs; ++i)
+ enable_irq_wake(encoder->irq[i]);
}
return 0;
@@ -342,10 +313,11 @@ static int __maybe_unused rotary_encoder_suspend(struct device *dev)
static int __maybe_unused rotary_encoder_resume(struct device *dev)
{
struct rotary_encoder *encoder = dev_get_drvdata(dev);
+ unsigned int i;
if (device_may_wakeup(dev)) {
- disable_irq_wake(encoder->irq_a);
- disable_irq_wake(encoder->irq_b);
+ for (i = 0; i < encoder->gpios->ndescs; ++i)
+ disable_irq_wake(encoder->irq[i]);
}
return 0;
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-10 13:35:15 +0000