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15#include <linux/delay.h>
16#include <linux/errno.h>
17#include <linux/input.h>
18#include <linux/interrupt.h>
19#include <linux/kernel.h>
20#include <linux/log2.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/platform_device.h>
24#include <linux/reboot.h>
25#include <linux/regmap.h>
26
27#define PON_REV2 0x01
28
29#define PON_RT_STS 0x10
30#define PON_KPDPWR_N_SET BIT(0)
31
32#define PON_PS_HOLD_RST_CTL 0x5a
33#define PON_PS_HOLD_RST_CTL2 0x5b
34#define PON_PS_HOLD_ENABLE BIT(7)
35#define PON_PS_HOLD_TYPE_MASK 0x0f
36#define PON_PS_HOLD_TYPE_SHUTDOWN 4
37#define PON_PS_HOLD_TYPE_HARD_RESET 7
38
39#define PON_PULL_CTL 0x70
40#define PON_KPDPWR_PULL_UP BIT(1)
41
42#define PON_DBC_CTL 0x71
43#define PON_DBC_DELAY_MASK 0x7
44
45
46struct pm8941_pwrkey {
47 struct device *dev;
48 int irq;
49 u32 baseaddr;
50 struct regmap *regmap;
51 struct input_dev *input;
52
53 unsigned int revision;
54 struct notifier_block reboot_notifier;
55};
56
57static int pm8941_reboot_notify(struct notifier_block *nb,
58 unsigned long code, void *unused)
59{
60 struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
61 reboot_notifier);
62 unsigned int enable_reg;
63 unsigned int reset_type;
64 int error;
65
66
67 if (pwrkey->revision == 0)
68 enable_reg = PON_PS_HOLD_RST_CTL;
69 else
70 enable_reg = PON_PS_HOLD_RST_CTL2;
71
72 error = regmap_update_bits(pwrkey->regmap,
73 pwrkey->baseaddr + enable_reg,
74 PON_PS_HOLD_ENABLE,
75 0);
76 if (error)
77 dev_err(pwrkey->dev,
78 "unable to clear ps hold reset enable: %d\n",
79 error);
80
81
82
83
84
85 usleep_range(100, 1000);
86
87 switch (code) {
88 case SYS_HALT:
89 case SYS_POWER_OFF:
90 reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
91 break;
92 case SYS_RESTART:
93 default:
94 reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
95 break;
96 }
97
98 error = regmap_update_bits(pwrkey->regmap,
99 pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
100 PON_PS_HOLD_TYPE_MASK,
101 reset_type);
102 if (error)
103 dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
104 error);
105
106 error = regmap_update_bits(pwrkey->regmap,
107 pwrkey->baseaddr + enable_reg,
108 PON_PS_HOLD_ENABLE,
109 PON_PS_HOLD_ENABLE);
110 if (error)
111 dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
112
113 return NOTIFY_DONE;
114}
115
116static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
117{
118 struct pm8941_pwrkey *pwrkey = _data;
119 unsigned int sts;
120 int error;
121
122 error = regmap_read(pwrkey->regmap,
123 pwrkey->baseaddr + PON_RT_STS, &sts);
124 if (error)
125 return IRQ_HANDLED;
126
127 input_report_key(pwrkey->input, KEY_POWER, !!(sts & PON_KPDPWR_N_SET));
128 input_sync(pwrkey->input);
129
130 return IRQ_HANDLED;
131}
132
133static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
134{
135 struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
136
137 if (device_may_wakeup(dev))
138 enable_irq_wake(pwrkey->irq);
139
140 return 0;
141}
142
143static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
144{
145 struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
146
147 if (device_may_wakeup(dev))
148 disable_irq_wake(pwrkey->irq);
149
150 return 0;
151}
152
153static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
154 pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
155
156static int pm8941_pwrkey_probe(struct platform_device *pdev)
157{
158 struct pm8941_pwrkey *pwrkey;
159 bool pull_up;
160 u32 req_delay;
161 int error;
162
163 if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
164 req_delay = 15625;
165
166 if (req_delay > 2000000 || req_delay == 0) {
167 dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
168 return -EINVAL;
169 }
170
171 pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
172
173 pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
174 if (!pwrkey)
175 return -ENOMEM;
176
177 pwrkey->dev = &pdev->dev;
178
179 pwrkey->regmap = dev_get_regmap(pdev->dev.parent, NULL);
180 if (!pwrkey->regmap) {
181 dev_err(&pdev->dev, "failed to locate regmap\n");
182 return -ENODEV;
183 }
184
185 pwrkey->irq = platform_get_irq(pdev, 0);
186 if (pwrkey->irq < 0) {
187 dev_err(&pdev->dev, "failed to get irq\n");
188 return pwrkey->irq;
189 }
190
191 error = of_property_read_u32(pdev->dev.of_node, "reg",
192 &pwrkey->baseaddr);
193 if (error)
194 return error;
195
196 error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
197 &pwrkey->revision);
198 if (error) {
199 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
200 return error;
201 }
202
203 pwrkey->input = devm_input_allocate_device(&pdev->dev);
204 if (!pwrkey->input) {
205 dev_dbg(&pdev->dev, "unable to allocate input device\n");
206 return -ENOMEM;
207 }
208
209 input_set_capability(pwrkey->input, EV_KEY, KEY_POWER);
210
211 pwrkey->input->name = "pm8941_pwrkey";
212 pwrkey->input->phys = "pm8941_pwrkey/input0";
213
214 req_delay = (req_delay << 6) / USEC_PER_SEC;
215 req_delay = ilog2(req_delay);
216
217 error = regmap_update_bits(pwrkey->regmap,
218 pwrkey->baseaddr + PON_DBC_CTL,
219 PON_DBC_DELAY_MASK,
220 req_delay);
221 if (error) {
222 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
223 return error;
224 }
225
226 error = regmap_update_bits(pwrkey->regmap,
227 pwrkey->baseaddr + PON_PULL_CTL,
228 PON_KPDPWR_PULL_UP,
229 pull_up ? PON_KPDPWR_PULL_UP : 0);
230 if (error) {
231 dev_err(&pdev->dev, "failed to set pull: %d\n", error);
232 return error;
233 }
234
235 error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
236 NULL, pm8941_pwrkey_irq,
237 IRQF_ONESHOT,
238 "pm8941_pwrkey", pwrkey);
239 if (error) {
240 dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
241 return error;
242 }
243
244 error = input_register_device(pwrkey->input);
245 if (error) {
246 dev_err(&pdev->dev, "failed to register input device: %d\n",
247 error);
248 return error;
249 }
250
251 pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,
252 error = register_reboot_notifier(&pwrkey->reboot_notifier);
253 if (error) {
254 dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
255 error);
256 return error;
257 }
258
259 platform_set_drvdata(pdev, pwrkey);
260 device_init_wakeup(&pdev->dev, 1);
261
262 return 0;
263}
264
265static int pm8941_pwrkey_remove(struct platform_device *pdev)
266{
267 struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
268
269 device_init_wakeup(&pdev->dev, 0);
270 unregister_reboot_notifier(&pwrkey->reboot_notifier);
271
272 return 0;
273}
274
275static const struct of_device_id pm8941_pwr_key_id_table[] = {
276 { .compatible = "qcom,pm8941-pwrkey" },
277 { }
278};
279MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
280
281static struct platform_driver pm8941_pwrkey_driver = {
282 .probe = pm8941_pwrkey_probe,
283 .remove = pm8941_pwrkey_remove,
284 .driver = {
285 .name = "pm8941-pwrkey",
286 .pm = &pm8941_pwr_key_pm_ops,
287 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
288 },
289};
290module_platform_driver(pm8941_pwrkey_driver);
291
292MODULE_DESCRIPTION("PM8941 Power Key driver");
293MODULE_LICENSE("GPL v2");
294
