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