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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/input/keyboard/gpio_keys_polled.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/keyboard/gpio_keys_polled.c')
-rw-r--r--drivers/input/keyboard/gpio_keys_polled.c391
1 files changed, 391 insertions, 0 deletions
diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c
new file mode 100644
index 000000000..c3937d2fc
--- /dev/null
+++ b/drivers/input/keyboard/gpio_keys_polled.c
@@ -0,0 +1,391 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for buttons on GPIO lines not capable of generating interrupts
+ *
+ * Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
+ *
+ * This file was based on: /drivers/input/misc/cobalt_btns.c
+ * Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
+ *
+ * also was based on: /drivers/input/keyboard/gpio_keys.c
+ * Copyright 2005 Phil Blundell
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio_keys.h>
+#include <linux/property.h>
+
+#define DRV_NAME "gpio-keys-polled"
+
+struct gpio_keys_button_data {
+ struct gpio_desc *gpiod;
+ int last_state;
+ int count;
+ int threshold;
+};
+
+struct gpio_keys_polled_dev {
+ struct input_dev *input;
+ struct device *dev;
+ const struct gpio_keys_platform_data *pdata;
+ unsigned long rel_axis_seen[BITS_TO_LONGS(REL_CNT)];
+ unsigned long abs_axis_seen[BITS_TO_LONGS(ABS_CNT)];
+ struct gpio_keys_button_data data[];
+};
+
+static void gpio_keys_button_event(struct input_dev *input,
+ const struct gpio_keys_button *button,
+ int state)
+{
+ struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
+ unsigned int type = button->type ?: EV_KEY;
+
+ if (type == EV_REL) {
+ if (state) {
+ input_event(input, type, button->code, button->value);
+ __set_bit(button->code, bdev->rel_axis_seen);
+ }
+ } else if (type == EV_ABS) {
+ if (state) {
+ input_event(input, type, button->code, button->value);
+ __set_bit(button->code, bdev->abs_axis_seen);
+ }
+ } else {
+ input_event(input, type, button->code, state);
+ input_sync(input);
+ }
+}
+
+static void gpio_keys_polled_check_state(struct input_dev *input,
+ const struct gpio_keys_button *button,
+ struct gpio_keys_button_data *bdata)
+{
+ int state;
+
+ state = gpiod_get_value_cansleep(bdata->gpiod);
+ if (state < 0) {
+ dev_err(input->dev.parent,
+ "failed to get gpio state: %d\n", state);
+ } else {
+ gpio_keys_button_event(input, button, state);
+
+ if (state != bdata->last_state) {
+ bdata->count = 0;
+ bdata->last_state = state;
+ }
+ }
+}
+
+static void gpio_keys_polled_poll(struct input_dev *input)
+{
+ struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
+ const struct gpio_keys_platform_data *pdata = bdev->pdata;
+ int i;
+
+ memset(bdev->rel_axis_seen, 0, sizeof(bdev->rel_axis_seen));
+ memset(bdev->abs_axis_seen, 0, sizeof(bdev->abs_axis_seen));
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+ struct gpio_keys_button_data *bdata = &bdev->data[i];
+
+ if (bdata->count < bdata->threshold) {
+ bdata->count++;
+ gpio_keys_button_event(input, &pdata->buttons[i],
+ bdata->last_state);
+ } else {
+ gpio_keys_polled_check_state(input, &pdata->buttons[i],
+ bdata);
+ }
+ }
+
+ for_each_set_bit(i, input->relbit, REL_CNT) {
+ if (!test_bit(i, bdev->rel_axis_seen))
+ input_event(input, EV_REL, i, 0);
+ }
+
+ for_each_set_bit(i, input->absbit, ABS_CNT) {
+ if (!test_bit(i, bdev->abs_axis_seen))
+ input_event(input, EV_ABS, i, 0);
+ }
+
+ input_sync(input);
+}
+
+static int gpio_keys_polled_open(struct input_dev *input)
+{
+ struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
+ const struct gpio_keys_platform_data *pdata = bdev->pdata;
+
+ if (pdata->enable)
+ pdata->enable(bdev->dev);
+
+ return 0;
+}
+
+static void gpio_keys_polled_close(struct input_dev *input)
+{
+ struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
+ const struct gpio_keys_platform_data *pdata = bdev->pdata;
+
+ if (pdata->disable)
+ pdata->disable(bdev->dev);
+}
+
+static struct gpio_keys_platform_data *
+gpio_keys_polled_get_devtree_pdata(struct device *dev)
+{
+ struct gpio_keys_platform_data *pdata;
+ struct gpio_keys_button *button;
+ struct fwnode_handle *child;
+ int nbuttons;
+
+ nbuttons = device_get_child_node_count(dev);
+ if (nbuttons == 0)
+ return ERR_PTR(-EINVAL);
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * sizeof(*button),
+ GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ button = (struct gpio_keys_button *)(pdata + 1);
+
+ pdata->buttons = button;
+ pdata->nbuttons = nbuttons;
+
+ pdata->rep = device_property_present(dev, "autorepeat");
+ device_property_read_u32(dev, "poll-interval", &pdata->poll_interval);
+
+ device_property_read_string(dev, "label", &pdata->name);
+
+ device_for_each_child_node(dev, child) {
+ if (fwnode_property_read_u32(child, "linux,code",
+ &button->code)) {
+ dev_err(dev, "button without keycode\n");
+ fwnode_handle_put(child);
+ return ERR_PTR(-EINVAL);
+ }
+
+ fwnode_property_read_string(child, "label", &button->desc);
+
+ if (fwnode_property_read_u32(child, "linux,input-type",
+ &button->type))
+ button->type = EV_KEY;
+
+ if (fwnode_property_read_u32(child, "linux,input-value",
+ (u32 *)&button->value))
+ button->value = 1;
+
+ button->wakeup =
+ fwnode_property_read_bool(child, "wakeup-source") ||
+ /* legacy name */
+ fwnode_property_read_bool(child, "gpio-key,wakeup");
+
+ if (fwnode_property_read_u32(child, "debounce-interval",
+ &button->debounce_interval))
+ button->debounce_interval = 5;
+
+ button++;
+ }
+
+ return pdata;
+}
+
+static void gpio_keys_polled_set_abs_params(struct input_dev *input,
+ const struct gpio_keys_platform_data *pdata, unsigned int code)
+{
+ int i, min = 0, max = 0;
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+ const struct gpio_keys_button *button = &pdata->buttons[i];
+
+ if (button->type != EV_ABS || button->code != code)
+ continue;
+
+ if (button->value < min)
+ min = button->value;
+ if (button->value > max)
+ max = button->value;
+ }
+
+ input_set_abs_params(input, code, min, max, 0, 0);
+}
+
+static const struct of_device_id gpio_keys_polled_of_match[] = {
+ { .compatible = "gpio-keys-polled", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
+
+static int gpio_keys_polled_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct fwnode_handle *child = NULL;
+ const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
+ struct gpio_keys_polled_dev *bdev;
+ struct input_dev *input;
+ int error;
+ int i;
+
+ if (!pdata) {
+ pdata = gpio_keys_polled_get_devtree_pdata(dev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ }
+
+ if (!pdata->poll_interval) {
+ dev_err(dev, "missing poll_interval value\n");
+ return -EINVAL;
+ }
+
+ bdev = devm_kzalloc(dev, struct_size(bdev, data, pdata->nbuttons),
+ GFP_KERNEL);
+ if (!bdev) {
+ dev_err(dev, "no memory for private data\n");
+ return -ENOMEM;
+ }
+
+ input = devm_input_allocate_device(dev);
+ if (!input) {
+ dev_err(dev, "no memory for input device\n");
+ return -ENOMEM;
+ }
+
+ input_set_drvdata(input, bdev);
+
+ input->name = pdata->name ?: pdev->name;
+ input->phys = DRV_NAME"/input0";
+
+ input->id.bustype = BUS_HOST;
+ input->id.vendor = 0x0001;
+ input->id.product = 0x0001;
+ input->id.version = 0x0100;
+
+ input->open = gpio_keys_polled_open;
+ input->close = gpio_keys_polled_close;
+
+ __set_bit(EV_KEY, input->evbit);
+ if (pdata->rep)
+ __set_bit(EV_REP, input->evbit);
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+ const struct gpio_keys_button *button = &pdata->buttons[i];
+ struct gpio_keys_button_data *bdata = &bdev->data[i];
+ unsigned int type = button->type ?: EV_KEY;
+
+ if (button->wakeup) {
+ dev_err(dev, DRV_NAME " does not support wakeup\n");
+ fwnode_handle_put(child);
+ return -EINVAL;
+ }
+
+ if (!dev_get_platdata(dev)) {
+ /* No legacy static platform data */
+ child = device_get_next_child_node(dev, child);
+ if (!child) {
+ dev_err(dev, "missing child device node\n");
+ return -EINVAL;
+ }
+
+ bdata->gpiod = devm_fwnode_gpiod_get(dev, child,
+ NULL, GPIOD_IN,
+ button->desc);
+ if (IS_ERR(bdata->gpiod)) {
+ error = PTR_ERR(bdata->gpiod);
+ if (error != -EPROBE_DEFER)
+ dev_err(dev,
+ "failed to get gpio: %d\n",
+ error);
+ fwnode_handle_put(child);
+ return error;
+ }
+ } else if (gpio_is_valid(button->gpio)) {
+ /*
+ * Legacy GPIO number so request the GPIO here and
+ * convert it to descriptor.
+ */
+ unsigned flags = GPIOF_IN;
+
+ if (button->active_low)
+ flags |= GPIOF_ACTIVE_LOW;
+
+ error = devm_gpio_request_one(dev, button->gpio,
+ flags, button->desc ? : DRV_NAME);
+ if (error) {
+ dev_err(dev,
+ "unable to claim gpio %u, err=%d\n",
+ button->gpio, error);
+ return error;
+ }
+
+ bdata->gpiod = gpio_to_desc(button->gpio);
+ if (!bdata->gpiod) {
+ dev_err(dev,
+ "unable to convert gpio %u to descriptor\n",
+ button->gpio);
+ return -EINVAL;
+ }
+ }
+
+ bdata->last_state = -1;
+ bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
+ pdata->poll_interval);
+
+ input_set_capability(input, type, button->code);
+ if (type == EV_ABS)
+ gpio_keys_polled_set_abs_params(input, pdata,
+ button->code);
+ }
+
+ fwnode_handle_put(child);
+
+ bdev->input = input;
+ bdev->dev = dev;
+ bdev->pdata = pdata;
+
+ error = input_setup_polling(input, gpio_keys_polled_poll);
+ if (error) {
+ dev_err(dev, "unable to set up polling, err=%d\n", error);
+ return error;
+ }
+
+ input_set_poll_interval(input, pdata->poll_interval);
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(dev, "unable to register polled device, err=%d\n",
+ error);
+ return error;
+ }
+
+ /* report initial state of the buttons */
+ for (i = 0; i < pdata->nbuttons; i++)
+ gpio_keys_polled_check_state(input, &pdata->buttons[i],
+ &bdev->data[i]);
+
+ input_sync(input);
+
+ return 0;
+}
+
+static struct platform_driver gpio_keys_polled_driver = {
+ .probe = gpio_keys_polled_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = gpio_keys_polled_of_match,
+ },
+};
+module_platform_driver(gpio_keys_polled_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
+MODULE_DESCRIPTION("Polled GPIO Buttons driver");
+MODULE_ALIAS("platform:" DRV_NAME);