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Diffstat (limited to '')
| -rw-r--r-- | drivers/input/misc/palmas-pwrbutton.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/input/misc/palmas-pwrbutton.c b/drivers/input/misc/palmas-pwrbutton.c new file mode 100644 index 000000000..1e1baed63 --- /dev/null +++ b/drivers/input/misc/palmas-pwrbutton.c @@ -0,0 +1,329 @@ +/* + * 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, ®); + 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; +} + +/** + * 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 __maybe_unused 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 __maybe_unused 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; +} + +static SIMPLE_DEV_PM_OPS(palmas_pwron_pm, + palmas_pwron_suspend, palmas_pwron_resume); + +#ifdef CONFIG_OF +static const 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", + .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."); |