diff options
Diffstat (limited to 'drivers/input/misc/rotary_encoder.c')
-rw-r--r-- | drivers/input/misc/rotary_encoder.c | 403 |
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, |