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path: root/drivers/input/misc/rotary_encoder.c
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Diffstat (limited to 'drivers/input/misc/rotary_encoder.c')
-rw-r--r--drivers/input/misc/rotary_encoder.c403
1 files changed, 153 insertions, 250 deletions
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 8aee71986430..96c486de49e0 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -20,70 +20,78 @@
#include <linux/input.h>
#include <linux/device.h>
#include <linux/platform_device.h>
-#include <linux/gpio.h>
-#include <linux/rotary_encoder.h>
+#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <linux/of.h>
-#include <linux/of_platform.h>
-#include <linux/of_gpio.h>
#include <linux/pm.h>
+#include <linux/property.h>
#define DRV_NAME "rotary-encoder"
struct rotary_encoder {
struct input_dev *input;
- const struct rotary_encoder_platform_data *pdata;
- unsigned int axis;
+ struct mutex access_mutex;
+
+ u32 steps;
+ u32 axis;
+ bool relative_axis;
+ bool rollover;
+
unsigned int pos;
- unsigned int irq_a;
- unsigned int irq_b;
+ struct gpio_descs *gpios;
+
+ 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(const struct rotary_encoder_platform_data *pdata)
+static unsigned rotary_encoder_get_state(struct rotary_encoder *encoder)
{
- int a = !!gpio_get_value(pdata->gpio_a);
- int b = !!gpio_get_value(pdata->gpio_b);
+ int i;
+ unsigned ret = 0;
- a ^= pdata->inverted_a;
- b ^= pdata->inverted_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;
- return ((a << 1) | b);
+ ret = ret << 1 | val;
+ }
+
+ return ret & 3;
}
static void rotary_encoder_report_event(struct rotary_encoder *encoder)
{
- const struct rotary_encoder_platform_data *pdata = encoder->pdata;
-
- if (pdata->relative_axis) {
+ if (encoder->relative_axis) {
input_report_rel(encoder->input,
- pdata->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 (pdata->rollover)
- pos += pdata->steps;
+ if (encoder->rollover)
+ pos += encoder->steps;
if (pos)
pos--;
} else {
/* turning clockwise */
- if (pdata->rollover || pos < pdata->steps)
+ if (encoder->rollover || pos < encoder->steps)
pos++;
}
- if (pdata->rollover)
- pos %= pdata->steps;
+ if (encoder->rollover)
+ pos %= encoder->steps;
encoder->pos = pos;
- input_report_abs(encoder->input, pdata->axis, encoder->pos);
+ input_report_abs(encoder->input, encoder->axis, encoder->pos);
}
input_sync(encoder->input);
@@ -92,9 +100,11 @@ 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;
- state = rotary_encoder_get_state(encoder->pdata);
+ mutex_lock(&encoder->access_mutex);
+
+ state = rotary_encoder_get_state(encoder);
switch (state) {
case 0x0:
@@ -105,334 +115,227 @@ 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;
}
+ mutex_unlock(&encoder->access_mutex);
+
return IRQ_HANDLED;
}
static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
{
struct rotary_encoder *encoder = dev_id;
- int state;
+ unsigned int state;
- state = rotary_encoder_get_state(encoder->pdata);
+ mutex_lock(&encoder->access_mutex);
- switch (state) {
- case 0x00:
- case 0x03:
+ state = rotary_encoder_get_state(encoder);
+
+ 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);
+
return IRQ_HANDLED;
}
static irqreturn_t rotary_encoder_quarter_period_irq(int irq, void *dev_id)
{
struct rotary_encoder *encoder = dev_id;
- unsigned char sum;
- int state;
-
- state = rotary_encoder_get_state(encoder->pdata);
-
- /*
- * 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;
+ unsigned int state;
- case 0x13:
- case 0x01:
- case 0x20:
- case 0x32:
- encoder->dir = 1; /* counter-clockwise */
- break;
+ mutex_lock(&encoder->access_mutex);
- 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.
- */
+ state = rotary_encoder_get_state(encoder);
+
+ 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);
out:
encoder->last_stable = state;
+ mutex_unlock(&encoder->access_mutex);
+
return IRQ_HANDLED;
}
-#ifdef CONFIG_OF
-static const struct of_device_id rotary_encoder_of_match[] = {
- { .compatible = "rotary-encoder", },
- { },
-};
-MODULE_DEVICE_TABLE(of, rotary_encoder_of_match);
-
-static struct rotary_encoder_platform_data *rotary_encoder_parse_dt(struct device *dev)
+static int rotary_encoder_probe(struct platform_device *pdev)
{
- const struct of_device_id *of_id =
- of_match_device(rotary_encoder_of_match, dev);
- struct device_node *np = dev->of_node;
- struct rotary_encoder_platform_data *pdata;
- enum of_gpio_flags flags;
- int error;
-
- if (!of_id || !np)
- return NULL;
-
- pdata = kzalloc(sizeof(struct rotary_encoder_platform_data),
- GFP_KERNEL);
- if (!pdata)
- return ERR_PTR(-ENOMEM);
-
- of_property_read_u32(np, "rotary-encoder,steps", &pdata->steps);
- of_property_read_u32(np, "linux,axis", &pdata->axis);
+ struct device *dev = &pdev->dev;
+ struct rotary_encoder *encoder;
+ struct input_dev *input;
+ irq_handler_t handler;
+ u32 steps_per_period;
+ unsigned int i;
+ int err;
- pdata->gpio_a = of_get_gpio_flags(np, 0, &flags);
- pdata->inverted_a = flags & OF_GPIO_ACTIVE_LOW;
+ encoder = devm_kzalloc(dev, sizeof(struct rotary_encoder), GFP_KERNEL);
+ if (!encoder)
+ return -ENOMEM;
- pdata->gpio_b = of_get_gpio_flags(np, 1, &flags);
- pdata->inverted_b = flags & OF_GPIO_ACTIVE_LOW;
+ mutex_init(&encoder->access_mutex);
- pdata->relative_axis =
- of_property_read_bool(np, "rotary-encoder,relative-axis");
- pdata->rollover = of_property_read_bool(np, "rotary-encoder,rollover");
+ device_property_read_u32(dev, "rotary-encoder,steps", &encoder->steps);
- error = of_property_read_u32(np, "rotary-encoder,steps-per-period",
- &pdata->steps_per_period);
- if (error) {
+ err = device_property_read_u32(dev, "rotary-encoder,steps-per-period",
+ &steps_per_period);
+ if (err) {
/*
- * The 'half-period' property has been deprecated, you must use
- * 'steps-per-period' and set an appropriate value, but we still
- * need to parse it to maintain compatibility.
+ * The 'half-period' property has been deprecated, you must
+ * use 'steps-per-period' and set an appropriate value, but
+ * we still need to parse it to maintain compatibility. If
+ * neither property is present we fall back to the one step
+ * per period behavior.
*/
- if (of_property_read_bool(np, "rotary-encoder,half-period")) {
- pdata->steps_per_period = 2;
- } else {
- /* Fallback to one step per period behavior */
- pdata->steps_per_period = 1;
- }
+ steps_per_period = device_property_read_bool(dev,
+ "rotary-encoder,half-period") ? 2 : 1;
}
- pdata->wakeup_source = of_property_read_bool(np, "wakeup-source");
+ encoder->rollover =
+ device_property_read_bool(dev, "rotary-encoder,rollover");
- return pdata;
-}
-#else
-static inline struct rotary_encoder_platform_data *
-rotary_encoder_parse_dt(struct device *dev)
-{
- return NULL;
-}
-#endif
-
-static int rotary_encoder_probe(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- const struct rotary_encoder_platform_data *pdata = dev_get_platdata(dev);
- struct rotary_encoder *encoder;
- struct input_dev *input;
- irq_handler_t handler;
- int err;
-
- if (!pdata) {
- pdata = rotary_encoder_parse_dt(dev);
- if (IS_ERR(pdata))
- return PTR_ERR(pdata);
+ device_property_read_u32(dev, "linux,axis", &encoder->axis);
+ encoder->relative_axis =
+ device_property_read_bool(dev, "rotary-encoder,relative-axis");
- if (!pdata) {
- dev_err(dev, "missing platform data\n");
- return -EINVAL;
- }
+ 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 = kzalloc(sizeof(struct rotary_encoder), GFP_KERNEL);
- input = input_allocate_device();
- if (!encoder || !input) {
- err = -ENOMEM;
- goto exit_free_mem;
+ if (encoder->gpios->ndescs < 2) {
+ dev_err(dev, "not enough gpios found\n");
+ return -EINVAL;
}
+ input = devm_input_allocate_device(dev);
+ if (!input)
+ return -ENOMEM;
+
encoder->input = input;
- encoder->pdata = pdata;
input->name = pdev->name;
input->id.bustype = BUS_HOST;
input->dev.parent = dev;
- if (pdata->relative_axis) {
- input->evbit[0] = BIT_MASK(EV_REL);
- input->relbit[0] = BIT_MASK(pdata->axis);
- } else {
- input->evbit[0] = BIT_MASK(EV_ABS);
- input_set_abs_params(encoder->input,
- pdata->axis, 0, pdata->steps, 0, 1);
- }
-
- /* request the GPIOs */
- err = gpio_request_one(pdata->gpio_a, GPIOF_IN, dev_name(dev));
- if (err) {
- dev_err(dev, "unable to request GPIO %d\n", pdata->gpio_a);
- goto exit_free_mem;
- }
-
- err = gpio_request_one(pdata->gpio_b, GPIOF_IN, dev_name(dev));
- if (err) {
- dev_err(dev, "unable to request GPIO %d\n", pdata->gpio_b);
- goto exit_free_gpio_a;
- }
-
- encoder->irq_a = gpio_to_irq(pdata->gpio_a);
- encoder->irq_b = gpio_to_irq(pdata->gpio_b);
+ if (encoder->relative_axis)
+ input_set_capability(input, EV_REL, encoder->axis);
+ else
+ input_set_abs_params(input,
+ encoder->axis, 0, encoder->steps, 0, 1);
- switch (pdata->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(pdata);
+ encoder->last_stable = rotary_encoder_get_state(encoder);
break;
case 2:
handler = &rotary_encoder_half_period_irq;
- encoder->last_stable = rotary_encoder_get_state(pdata);
+ encoder->last_stable = rotary_encoder_get_state(encoder);
break;
case 1:
handler = &rotary_encoder_irq;
break;
default:
dev_err(dev, "'%d' is not a valid steps-per-period value\n",
- pdata->steps_per_period);
- err = -EINVAL;
- goto exit_free_gpio_b;
+ steps_per_period);
+ return -EINVAL;
}
- err = request_irq(encoder->irq_a, handler,
- IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
- DRV_NAME, encoder);
- if (err) {
- dev_err(dev, "unable to request IRQ %d\n", encoder->irq_a);
- goto exit_free_gpio_b;
- }
-
- err = request_irq(encoder->irq_b, handler,
- IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
- DRV_NAME, encoder);
- if (err) {
- dev_err(dev, "unable to request IRQ %d\n", encoder->irq_b);
- goto exit_free_irq_a;
+ encoder->irq =
+ devm_kzalloc(dev,
+ sizeof(*encoder->irq) * encoder->gpios->ndescs,
+ GFP_KERNEL);
+ if (!encoder->irq)
+ return -ENOMEM;
+
+ 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 (gpio#%d)\n",
+ encoder->irq[i], i);
+ return err;
+ }
}
err = input_register_device(input);
if (err) {
dev_err(dev, "failed to register input device\n");
- goto exit_free_irq_b;
+ return err;
}
- device_init_wakeup(&pdev->dev, pdata->wakeup_source);
+ device_init_wakeup(dev,
+ device_property_read_bool(dev, "wakeup-source"));
platform_set_drvdata(pdev, encoder);
return 0;
-
-exit_free_irq_b:
- free_irq(encoder->irq_b, encoder);
-exit_free_irq_a:
- free_irq(encoder->irq_a, encoder);
-exit_free_gpio_b:
- gpio_free(pdata->gpio_b);
-exit_free_gpio_a:
- gpio_free(pdata->gpio_a);
-exit_free_mem:
- input_free_device(input);
- kfree(encoder);
- if (!dev_get_platdata(&pdev->dev))
- kfree(pdata);
-
- return err;
}
-static int rotary_encoder_remove(struct platform_device *pdev)
-{
- struct rotary_encoder *encoder = platform_get_drvdata(pdev);
- const struct rotary_encoder_platform_data *pdata = encoder->pdata;
-
- device_init_wakeup(&pdev->dev, false);
-
- free_irq(encoder->irq_a, encoder);
- free_irq(encoder->irq_b, encoder);
- gpio_free(pdata->gpio_a);
- gpio_free(pdata->gpio_b);
-
- input_unregister_device(encoder->input);
- kfree(encoder);
-
- if (!dev_get_platdata(&pdev->dev))
- kfree(pdata);
-
- return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int rotary_encoder_suspend(struct device *dev)
+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;
}
-static int rotary_encoder_resume(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;
}
-#endif
static SIMPLE_DEV_PM_OPS(rotary_encoder_pm_ops,
- rotary_encoder_suspend, rotary_encoder_resume);
+ rotary_encoder_suspend, rotary_encoder_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id rotary_encoder_of_match[] = {
+ { .compatible = "rotary-encoder", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rotary_encoder_of_match);
+#endif
static struct platform_driver rotary_encoder_driver = {
.probe = rotary_encoder_probe,
- .remove = rotary_encoder_remove,
.driver = {
.name = DRV_NAME,
.pm = &rotary_encoder_pm_ops,