1 // SPDX-License-Identifier: GPL-2.0+
3 // Driver for the IMX SNVS ON/OFF Power Key
4 // Copyright (C) 2015 Freescale Semiconductor, Inc. All Rights Reserved.
7 #include <linux/device.h>
9 #include <linux/init.h>
10 #include <linux/input.h>
11 #include <linux/interrupt.h>
13 #include <linux/jiffies.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
17 #include <linux/of_address.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_wakeirq.h>
20 #include <linux/mfd/syscon.h>
21 #include <linux/regmap.h>
23 #define SNVS_HPVIDR1_REG 0xBF8
24 #define SNVS_LPSR_REG 0x4C /* LP Status Register */
25 #define SNVS_LPCR_REG 0x38 /* LP Control Register */
26 #define SNVS_HPSR_REG 0x14
27 #define SNVS_HPSR_BTN BIT(6)
28 #define SNVS_LPSR_SPO BIT(18)
29 #define SNVS_LPCR_DEP_EN BIT(5)
31 #define DEBOUNCE_TIME 30
32 #define REPEAT_INTERVAL 60
34 struct pwrkey_drv_data {
38 int keystate; /* 1:pressed */
40 struct timer_list check_timer;
41 struct input_dev *input;
45 static void imx_imx_snvs_check_for_events(struct timer_list *t)
47 struct pwrkey_drv_data *pdata = from_timer(pdata, t, check_timer);
48 struct input_dev *input = pdata->input;
51 regmap_read(pdata->snvs, SNVS_HPSR_REG, &state);
52 state = state & SNVS_HPSR_BTN ? 1 : 0;
54 /* only report new event if status changed */
55 if (state ^ pdata->keystate) {
56 pdata->keystate = state;
57 input_event(input, EV_KEY, pdata->keycode, state);
59 pm_relax(pdata->input->dev.parent);
62 /* repeat check if pressed long */
64 mod_timer(&pdata->check_timer,
65 jiffies + msecs_to_jiffies(REPEAT_INTERVAL));
69 static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id)
71 struct platform_device *pdev = dev_id;
72 struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
73 struct input_dev *input = pdata->input;
76 pm_wakeup_event(input->dev.parent, 0);
78 regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
79 if (lp_status & SNVS_LPSR_SPO) {
80 if (pdata->minor_rev == 0) {
82 * The first generation i.MX6 SoCs only sends an
83 * interrupt on button release. To mimic power-key
84 * usage, we'll prepend a press event.
86 input_report_key(input, pdata->keycode, 1);
88 input_report_key(input, pdata->keycode, 0);
90 pm_relax(input->dev.parent);
92 mod_timer(&pdata->check_timer,
93 jiffies + msecs_to_jiffies(DEBOUNCE_TIME));
97 /* clear SPO status */
98 regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
103 static void imx_snvs_pwrkey_disable_clk(void *data)
105 clk_disable_unprepare(data);
108 static void imx_snvs_pwrkey_act(void *pdata)
110 struct pwrkey_drv_data *pd = pdata;
112 del_timer_sync(&pd->check_timer);
115 static int imx_snvs_pwrkey_probe(struct platform_device *pdev)
117 struct pwrkey_drv_data *pdata;
118 struct input_dev *input;
119 struct device_node *np;
124 /* Get SNVS register Page */
125 np = pdev->dev.of_node;
129 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
133 pdata->snvs = syscon_regmap_lookup_by_phandle(np, "regmap");
134 if (IS_ERR(pdata->snvs)) {
135 dev_err(&pdev->dev, "Can't get snvs syscon\n");
136 return PTR_ERR(pdata->snvs);
139 if (of_property_read_u32(np, "linux,keycode", &pdata->keycode)) {
140 pdata->keycode = KEY_POWER;
141 dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
144 clk = devm_clk_get_optional(&pdev->dev, NULL);
146 dev_err(&pdev->dev, "Failed to get snvs clock (%pe)\n", clk);
150 error = clk_prepare_enable(clk);
152 dev_err(&pdev->dev, "Failed to enable snvs clock (%pe)\n",
157 error = devm_add_action_or_reset(&pdev->dev,
158 imx_snvs_pwrkey_disable_clk, clk);
161 "Failed to register clock cleanup handler (%pe)\n",
166 pdata->wakeup = of_property_read_bool(np, "wakeup-source");
168 pdata->irq = platform_get_irq(pdev, 0);
172 regmap_read(pdata->snvs, SNVS_HPVIDR1_REG, &vid);
173 pdata->minor_rev = vid & 0xff;
175 regmap_update_bits(pdata->snvs, SNVS_LPCR_REG, SNVS_LPCR_DEP_EN, SNVS_LPCR_DEP_EN);
177 /* clear the unexpected interrupt before driver ready */
178 regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
180 timer_setup(&pdata->check_timer, imx_imx_snvs_check_for_events, 0);
182 input = devm_input_allocate_device(&pdev->dev);
184 dev_err(&pdev->dev, "failed to allocate the input device\n");
188 input->name = pdev->name;
189 input->phys = "snvs-pwrkey/input0";
190 input->id.bustype = BUS_HOST;
192 input_set_capability(input, EV_KEY, pdata->keycode);
194 /* input customer action to cancel release timer */
195 error = devm_add_action(&pdev->dev, imx_snvs_pwrkey_act, pdata);
197 dev_err(&pdev->dev, "failed to register remove action\n");
201 pdata->input = input;
202 platform_set_drvdata(pdev, pdata);
204 error = devm_request_irq(&pdev->dev, pdata->irq,
205 imx_snvs_pwrkey_interrupt,
206 0, pdev->name, pdev);
209 dev_err(&pdev->dev, "interrupt not available.\n");
213 error = input_register_device(input);
215 dev_err(&pdev->dev, "failed to register input device\n");
219 device_init_wakeup(&pdev->dev, pdata->wakeup);
220 error = dev_pm_set_wake_irq(&pdev->dev, pdata->irq);
222 dev_err(&pdev->dev, "irq wake enable failed.\n");
227 static const struct of_device_id imx_snvs_pwrkey_ids[] = {
228 { .compatible = "fsl,sec-v4.0-pwrkey" },
231 MODULE_DEVICE_TABLE(of, imx_snvs_pwrkey_ids);
233 static struct platform_driver imx_snvs_pwrkey_driver = {
235 .name = "snvs_pwrkey",
236 .of_match_table = imx_snvs_pwrkey_ids,
238 .probe = imx_snvs_pwrkey_probe,
240 module_platform_driver(imx_snvs_pwrkey_driver);
242 MODULE_AUTHOR("Freescale Semiconductor");
243 MODULE_DESCRIPTION("i.MX snvs power key Driver");
244 MODULE_LICENSE("GPL");