2 * Driver for the IMX SNVS ON/OFF Power Key
3 * Copyright (C) 2015 Freescale Semiconductor, Inc. All Rights Reserved.
5 * The code contained herein is licensed under the GNU General Public
6 * License. You may obtain a copy of the GNU General Public License
7 * Version 2 or later at the following locations:
9 * http://www.opensource.org/licenses/gpl-license.html
10 * http://www.gnu.org/copyleft/gpl.html
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/input.h>
17 #include <linux/interrupt.h>
19 #include <linux/jiffies.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
23 #include <linux/of_address.h>
24 #include <linux/platform_device.h>
25 #include <linux/mfd/syscon.h>
26 #include <linux/regmap.h>
28 #define SNVS_LPSR_REG 0x4C /* LP Status Register */
29 #define SNVS_LPCR_REG 0x38 /* LP Control Register */
30 #define SNVS_HPSR_REG 0x14
31 #define SNVS_HPSR_BTN BIT(6)
32 #define SNVS_LPSR_SPO BIT(18)
33 #define SNVS_LPCR_DEP_EN BIT(5)
35 #define DEBOUNCE_TIME 30
36 #define REPEAT_INTERVAL 60
38 struct pwrkey_drv_data {
42 int keystate; /* 1:pressed */
44 struct timer_list check_timer;
45 struct input_dev *input;
48 static void imx_imx_snvs_check_for_events(unsigned long data)
50 struct pwrkey_drv_data *pdata = (struct pwrkey_drv_data *) data;
51 struct input_dev *input = pdata->input;
54 regmap_read(pdata->snvs, SNVS_HPSR_REG, &state);
55 state = state & SNVS_HPSR_BTN ? 1 : 0;
57 /* only report new event if status changed */
58 if (state ^ pdata->keystate) {
59 pdata->keystate = state;
60 input_event(input, EV_KEY, pdata->keycode, state);
62 pm_relax(pdata->input->dev.parent);
65 /* repeat check if pressed long */
67 mod_timer(&pdata->check_timer,
68 jiffies + msecs_to_jiffies(REPEAT_INTERVAL));
72 static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id)
74 struct platform_device *pdev = dev_id;
75 struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
78 pm_wakeup_event(pdata->input->dev.parent, 0);
80 regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
81 if (lp_status & SNVS_LPSR_SPO)
82 mod_timer(&pdata->check_timer, jiffies + msecs_to_jiffies(DEBOUNCE_TIME));
84 /* clear SPO status */
85 regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
90 static void imx_snvs_pwrkey_act(void *pdata)
92 struct pwrkey_drv_data *pd = pdata;
94 del_timer_sync(&pd->check_timer);
97 static int imx_snvs_pwrkey_probe(struct platform_device *pdev)
99 struct pwrkey_drv_data *pdata = NULL;
100 struct input_dev *input = NULL;
101 struct device_node *np;
104 /* Get SNVS register Page */
105 np = pdev->dev.of_node;
109 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
113 pdata->snvs = syscon_regmap_lookup_by_phandle(np, "regmap");;
116 dev_err(&pdev->dev, "Can't get snvs syscon\n");
120 if (of_property_read_u32(np, "linux,keycode", &pdata->keycode)) {
121 pdata->keycode = KEY_POWER;
122 dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
125 pdata->wakeup = of_property_read_bool(np, "wakeup-source");
127 pdata->irq = platform_get_irq(pdev, 0);
128 if (pdata->irq < 0) {
129 dev_err(&pdev->dev, "no irq defined in platform data\n");
133 regmap_update_bits(pdata->snvs, SNVS_LPCR_REG, SNVS_LPCR_DEP_EN, SNVS_LPCR_DEP_EN);
135 /* clear the unexpected interrupt before driver ready */
136 regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
138 setup_timer(&pdata->check_timer,
139 imx_imx_snvs_check_for_events, (unsigned long) pdata);
141 input = devm_input_allocate_device(&pdev->dev);
143 dev_err(&pdev->dev, "failed to allocate the input device\n");
147 input->name = pdev->name;
148 input->phys = "snvs-pwrkey/input0";
149 input->id.bustype = BUS_HOST;
151 input_set_capability(input, EV_KEY, pdata->keycode);
153 /* input customer action to cancel release timer */
154 error = devm_add_action(&pdev->dev, imx_snvs_pwrkey_act, pdata);
156 dev_err(&pdev->dev, "failed to register remove action\n");
160 error = devm_request_irq(&pdev->dev, pdata->irq,
161 imx_snvs_pwrkey_interrupt,
162 0, pdev->name, pdev);
165 dev_err(&pdev->dev, "interrupt not available.\n");
169 error = input_register_device(input);
171 dev_err(&pdev->dev, "failed to register input device\n");
172 input_free_device(input);
176 pdata->input = input;
177 platform_set_drvdata(pdev, pdata);
179 device_init_wakeup(&pdev->dev, pdata->wakeup);
184 static int imx_snvs_pwrkey_suspend(struct device *dev)
186 struct platform_device *pdev = to_platform_device(dev);
187 struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
189 if (device_may_wakeup(&pdev->dev))
190 enable_irq_wake(pdata->irq);
195 static int imx_snvs_pwrkey_resume(struct device *dev)
197 struct platform_device *pdev = to_platform_device(dev);
198 struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
200 if (device_may_wakeup(&pdev->dev))
201 disable_irq_wake(pdata->irq);
206 static const struct of_device_id imx_snvs_pwrkey_ids[] = {
207 { .compatible = "fsl,sec-v4.0-pwrkey" },
210 MODULE_DEVICE_TABLE(of, imx_snvs_pwrkey_ids);
212 static SIMPLE_DEV_PM_OPS(imx_snvs_pwrkey_pm_ops, imx_snvs_pwrkey_suspend,
213 imx_snvs_pwrkey_resume);
215 static struct platform_driver imx_snvs_pwrkey_driver = {
217 .name = "snvs_pwrkey",
218 .pm = &imx_snvs_pwrkey_pm_ops,
219 .of_match_table = imx_snvs_pwrkey_ids,
221 .probe = imx_snvs_pwrkey_probe,
223 module_platform_driver(imx_snvs_pwrkey_driver);
225 MODULE_AUTHOR("Freescale Semiconductor");
226 MODULE_DESCRIPTION("i.MX snvs power key Driver");
227 MODULE_LICENSE("GPL");