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path: root/drivers/input/misc/palmas-pwrbutton.c
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-rw-r--r--drivers/input/misc/palmas-pwrbutton.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/input/misc/palmas-pwrbutton.c b/drivers/input/misc/palmas-pwrbutton.c
new file mode 100644
index 000000000000..f505ac3a8d87
--- /dev/null
+++ b/drivers/input/misc/palmas-pwrbutton.c
@@ -0,0 +1,332 @@
+/*
+ * Texas Instruments' Palmas Power Button Input Driver
+ *
+ * Copyright (C) 2012-2014 Texas Instruments Incorporated - http://www.ti.com/
+ * Girish S Ghongdemath
+ * Nishanth Menon
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/palmas.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define PALMAS_LPK_TIME_MASK 0x0c
+#define PALMAS_PWRON_DEBOUNCE_MASK 0x03
+#define PALMAS_PWR_KEY_Q_TIME_MS 20
+
+/**
+ * struct palmas_pwron - Palmas power on data
+ * @palmas: pointer to palmas device
+ * @input_dev: pointer to input device
+ * @input_work: work for detecting release of key
+ * @irq: irq that we are hooked on to
+ */
+struct palmas_pwron {
+ struct palmas *palmas;
+ struct input_dev *input_dev;
+ struct delayed_work input_work;
+ int irq;
+};
+
+/**
+ * struct palmas_pwron_config - configuration of palmas power on
+ * @long_press_time_val: value for long press h/w shutdown event
+ * @pwron_debounce_val: value for debounce of power button
+ */
+struct palmas_pwron_config {
+ u8 long_press_time_val;
+ u8 pwron_debounce_val;
+};
+
+/**
+ * palmas_power_button_work() - Detects the button release event
+ * @work: work item to detect button release
+ */
+static void palmas_power_button_work(struct work_struct *work)
+{
+ struct palmas_pwron *pwron = container_of(work,
+ struct palmas_pwron,
+ input_work.work);
+ struct input_dev *input_dev = pwron->input_dev;
+ unsigned int reg;
+ int error;
+
+ error = palmas_read(pwron->palmas, PALMAS_INTERRUPT_BASE,
+ PALMAS_INT1_LINE_STATE, &reg);
+ if (error) {
+ dev_err(input_dev->dev.parent,
+ "Cannot read palmas PWRON status: %d\n", error);
+ } else if (reg & BIT(1)) {
+ /* The button is released, report event. */
+ input_report_key(input_dev, KEY_POWER, 0);
+ input_sync(input_dev);
+ } else {
+ /* The button is still depressed, keep checking. */
+ schedule_delayed_work(&pwron->input_work,
+ msecs_to_jiffies(PALMAS_PWR_KEY_Q_TIME_MS));
+ }
+}
+
+/**
+ * pwron_irq() - button press isr
+ * @irq: irq
+ * @palmas_pwron: pwron struct
+ *
+ * Return: IRQ_HANDLED
+ */
+static irqreturn_t pwron_irq(int irq, void *palmas_pwron)
+{
+ struct palmas_pwron *pwron = palmas_pwron;
+ struct input_dev *input_dev = pwron->input_dev;
+
+ input_report_key(input_dev, KEY_POWER, 1);
+ pm_wakeup_event(input_dev->dev.parent, 0);
+ input_sync(input_dev);
+
+ mod_delayed_work(system_wq, &pwron->input_work,
+ msecs_to_jiffies(PALMAS_PWR_KEY_Q_TIME_MS));
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * palmas_pwron_params_ofinit() - device tree parameter parser
+ * @dev: palmas button device
+ * @config: configuration params that this fills up
+ */
+static void palmas_pwron_params_ofinit(struct device *dev,
+ struct palmas_pwron_config *config)
+{
+ struct device_node *np;
+ u32 val;
+ int i, error;
+ u8 lpk_times[] = { 6, 8, 10, 12 };
+ int pwr_on_deb_ms[] = { 15, 100, 500, 1000 };
+
+ memset(config, 0, sizeof(*config));
+
+ /* Default config parameters */
+ config->long_press_time_val = ARRAY_SIZE(lpk_times) - 1;
+
+ np = dev->of_node;
+ if (!np)
+ return;
+
+ error = of_property_read_u32(np, "ti,palmas-long-press-seconds", &val);
+ if (!error) {
+ for (i = 0; i < ARRAY_SIZE(lpk_times); i++) {
+ if (val <= lpk_times[i]) {
+ config->long_press_time_val = i;
+ break;
+ }
+ }
+ }
+
+ error = of_property_read_u32(np,
+ "ti,palmas-pwron-debounce-milli-seconds",
+ &val);
+ if (!error) {
+ for (i = 0; i < ARRAY_SIZE(pwr_on_deb_ms); i++) {
+ if (val <= pwr_on_deb_ms[i]) {
+ config->pwron_debounce_val = i;
+ break;
+ }
+ }
+ }
+
+ dev_info(dev, "h/w controlled shutdown duration=%d seconds\n",
+ lpk_times[config->long_press_time_val]);
+}
+
+/**
+ * palmas_pwron_probe() - probe
+ * @pdev: platform device for the button
+ *
+ * Return: 0 for successful probe else appropriate error
+ */
+static int palmas_pwron_probe(struct platform_device *pdev)
+{
+ struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+ struct device *dev = &pdev->dev;
+ struct input_dev *input_dev;
+ struct palmas_pwron *pwron;
+ struct palmas_pwron_config config;
+ int val;
+ int error;
+
+ palmas_pwron_params_ofinit(dev, &config);
+
+ pwron = kzalloc(sizeof(*pwron), GFP_KERNEL);
+ if (!pwron)
+ return -ENOMEM;
+
+ input_dev = input_allocate_device();
+ if (!input_dev) {
+ dev_err(dev, "Can't allocate power button\n");
+ error = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ input_dev->name = "palmas_pwron";
+ input_dev->phys = "palmas_pwron/input0";
+ input_dev->dev.parent = dev;
+
+ input_set_capability(input_dev, EV_KEY, KEY_POWER);
+
+ /*
+ * Setup default hardware shutdown option (long key press)
+ * and debounce.
+ */
+ val = config.long_press_time_val << __ffs(PALMAS_LPK_TIME_MASK);
+ val |= config.pwron_debounce_val << __ffs(PALMAS_PWRON_DEBOUNCE_MASK);
+ error = palmas_update_bits(palmas, PALMAS_PMU_CONTROL_BASE,
+ PALMAS_LONG_PRESS_KEY,
+ PALMAS_LPK_TIME_MASK |
+ PALMAS_PWRON_DEBOUNCE_MASK,
+ val);
+ if (error) {
+ dev_err(dev, "LONG_PRESS_KEY_UPDATE failed: %d\n", error);
+ goto err_free_input;
+ }
+
+ pwron->palmas = palmas;
+ pwron->input_dev = input_dev;
+
+ INIT_DELAYED_WORK(&pwron->input_work, palmas_power_button_work);
+
+ pwron->irq = platform_get_irq(pdev, 0);
+ error = request_threaded_irq(pwron->irq, NULL, pwron_irq,
+ IRQF_TRIGGER_HIGH |
+ IRQF_TRIGGER_LOW |
+ IRQF_ONESHOT,
+ dev_name(dev), pwron);
+ if (error) {
+ dev_err(dev, "Can't get IRQ for pwron: %d\n", error);
+ goto err_free_input;
+ }
+
+ error = input_register_device(input_dev);
+ if (error) {
+ dev_err(dev, "Can't register power button: %d\n", error);
+ goto err_free_irq;
+ }
+
+ platform_set_drvdata(pdev, pwron);
+ device_init_wakeup(dev, true);
+
+ return 0;
+
+err_free_irq:
+ cancel_delayed_work_sync(&pwron->input_work);
+ free_irq(pwron->irq, pwron);
+err_free_input:
+ input_free_device(input_dev);
+err_free_mem:
+ kfree(pwron);
+ return error;
+}
+
+/**
+ * palmas_pwron_remove() - Cleanup on removal
+ * @pdev: platform device for the button
+ *
+ * Return: 0
+ */
+static int palmas_pwron_remove(struct platform_device *pdev)
+{
+ struct palmas_pwron *pwron = platform_get_drvdata(pdev);
+
+ free_irq(pwron->irq, pwron);
+ cancel_delayed_work_sync(&pwron->input_work);
+
+ input_unregister_device(pwron->input_dev);
+ kfree(pwron);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+/**
+ * palmas_pwron_suspend() - suspend handler
+ * @dev: power button device
+ *
+ * Cancel all pending work items for the power button, setup irq for wakeup
+ *
+ * Return: 0
+ */
+static int palmas_pwron_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct palmas_pwron *pwron = platform_get_drvdata(pdev);
+
+ cancel_delayed_work_sync(&pwron->input_work);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(pwron->irq);
+
+ return 0;
+}
+
+/**
+ * palmas_pwron_resume() - resume handler
+ * @dev: power button device
+ *
+ * Just disable the wakeup capability of irq here.
+ *
+ * Return: 0
+ */
+static int palmas_pwron_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct palmas_pwron *pwron = platform_get_drvdata(pdev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(pwron->irq);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(palmas_pwron_pm,
+ palmas_pwron_suspend, palmas_pwron_resume);
+
+#ifdef CONFIG_OF
+static struct of_device_id of_palmas_pwr_match[] = {
+ { .compatible = "ti,palmas-pwrbutton" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, of_palmas_pwr_match);
+#endif
+
+static struct platform_driver palmas_pwron_driver = {
+ .probe = palmas_pwron_probe,
+ .remove = palmas_pwron_remove,
+ .driver = {
+ .name = "palmas_pwrbutton",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(of_palmas_pwr_match),
+ .pm = &palmas_pwron_pm,
+ },
+};
+module_platform_driver(palmas_pwron_driver);
+
+MODULE_ALIAS("platform:palmas-pwrbutton");
+MODULE_DESCRIPTION("Palmas Power Button");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Texas Instruments Inc.");