1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  4 * Copyright (c) 2014, Sony Mobile Communications Inc.
  5 */
  6
  7#include <linux/delay.h>
  8#include <linux/errno.h>
  9#include <linux/input.h>
 10#include <linux/interrupt.h>
 11#include <linux/kernel.h>
 12#include <linux/log2.h>
 13#include <linux/module.h>
 14#include <linux/of.h>
 15#include <linux/of_device.h>
 16#include <linux/platform_device.h>
 17#include <linux/reboot.h>
 18#include <linux/regmap.h>
 19
 20#define PON_REV2			0x01
 21
 22#define PON_RT_STS			0x10
 23#define  PON_KPDPWR_N_SET		BIT(0)
 24#define  PON_RESIN_N_SET		BIT(1)
 25
 26#define PON_PS_HOLD_RST_CTL		0x5a
 27#define PON_PS_HOLD_RST_CTL2		0x5b
 28#define  PON_PS_HOLD_ENABLE		BIT(7)
 29#define  PON_PS_HOLD_TYPE_MASK		0x0f
 30#define  PON_PS_HOLD_TYPE_SHUTDOWN	4
 31#define  PON_PS_HOLD_TYPE_HARD_RESET	7
 32
 33#define PON_PULL_CTL			0x70
 34#define  PON_KPDPWR_PULL_UP		BIT(1)
 35#define  PON_RESIN_PULL_UP		BIT(0)
 36
 37#define PON_DBC_CTL			0x71
 38#define  PON_DBC_DELAY_MASK		0x7
 39
 40struct pm8941_data {
 41	unsigned int pull_up_bit;
 42	unsigned int status_bit;
 43};
 44
 45struct pm8941_pwrkey {
 46	struct device *dev;
 47	int irq;
 48	u32 baseaddr;
 49	struct regmap *regmap;
 50	struct input_dev *input;
 51
 52	unsigned int revision;
 53	struct notifier_block reboot_notifier;
 54
 55	u32 code;
 56	const struct pm8941_data *data;
 57};
 58
 59static int pm8941_reboot_notify(struct notifier_block *nb,
 60				unsigned long code, void *unused)
 61{
 62	struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
 63						    reboot_notifier);
 64	unsigned int enable_reg;
 65	unsigned int reset_type;
 66	int error;
 67
 68	/* PMICs with revision 0 have the enable bit in same register as ctrl */
 69	if (pwrkey->revision == 0)
 70		enable_reg = PON_PS_HOLD_RST_CTL;
 71	else
 72		enable_reg = PON_PS_HOLD_RST_CTL2;
 73
 74	error = regmap_update_bits(pwrkey->regmap,
 75				   pwrkey->baseaddr + enable_reg,
 76				   PON_PS_HOLD_ENABLE,
 77				   0);
 78	if (error)
 79		dev_err(pwrkey->dev,
 80			"unable to clear ps hold reset enable: %d\n",
 81			error);
 82
 83	/*
 84	 * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
 85	 * writes.
 86	 */
 87	usleep_range(100, 1000);
 88
 89	switch (code) {
 90	case SYS_HALT:
 91	case SYS_POWER_OFF:
 92		reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
 93		break;
 94	case SYS_RESTART:
 95	default:
 96		reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
 97		break;
 98	}
 99
100	error = regmap_update_bits(pwrkey->regmap,
101				   pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
102				   PON_PS_HOLD_TYPE_MASK,
103				   reset_type);
104	if (error)
105		dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
106			error);
107
108	error = regmap_update_bits(pwrkey->regmap,
109				   pwrkey->baseaddr + enable_reg,
110				   PON_PS_HOLD_ENABLE,
111				   PON_PS_HOLD_ENABLE);
112	if (error)
113		dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
114
115	return NOTIFY_DONE;
116}
117
118static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
119{
120	struct pm8941_pwrkey *pwrkey = _data;
121	unsigned int sts;
122	int error;
123
124	error = regmap_read(pwrkey->regmap,
125			    pwrkey->baseaddr + PON_RT_STS, &sts);
126	if (error)
127		return IRQ_HANDLED;
128
129	input_report_key(pwrkey->input, pwrkey->code,
130			 sts & pwrkey->data->status_bit);
131	input_sync(pwrkey->input);
132
133	return IRQ_HANDLED;
134}
135
136static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
137{
138	struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
139
140	if (device_may_wakeup(dev))
141		enable_irq_wake(pwrkey->irq);
142
143	return 0;
144}
145
146static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
147{
148	struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
149
150	if (device_may_wakeup(dev))
151		disable_irq_wake(pwrkey->irq);
152
153	return 0;
154}
155
156static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
157			 pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
158
159static int pm8941_pwrkey_probe(struct platform_device *pdev)
160{
161	struct pm8941_pwrkey *pwrkey;
162	bool pull_up;
163	struct device *parent;
164	u32 req_delay;
165	int error;
166
167	if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
168		req_delay = 15625;
169
170	if (req_delay > 2000000 || req_delay == 0) {
171		dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
172		return -EINVAL;
173	}
174
175	pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
176
177	pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
178	if (!pwrkey)
179		return -ENOMEM;
180
181	pwrkey->dev = &pdev->dev;
182	pwrkey->data = of_device_get_match_data(&pdev->dev);
183
184	parent = pdev->dev.parent;
185	pwrkey->regmap = dev_get_regmap(parent, NULL);
186	if (!pwrkey->regmap) {
187		/*
188		 * We failed to get regmap for parent. Let's see if we are
189		 * a child of pon node and read regmap and reg from its
190		 * parent.
191		 */
192		pwrkey->regmap = dev_get_regmap(parent->parent, NULL);
193		if (!pwrkey->regmap) {
194			dev_err(&pdev->dev, "failed to locate regmap\n");
195			return -ENODEV;
196		}
197
198		error = of_property_read_u32(parent->of_node,
199					     "reg", &pwrkey->baseaddr);
200	} else {
201		error = of_property_read_u32(pdev->dev.of_node, "reg",
202					     &pwrkey->baseaddr);
203	}
204	if (error)
205		return error;
206
207	pwrkey->irq = platform_get_irq(pdev, 0);
208	if (pwrkey->irq < 0)
209		return pwrkey->irq;
210
211	error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
212			    &pwrkey->revision);
213	if (error) {
214		dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
215		return error;
216	}
217
218	error = of_property_read_u32(pdev->dev.of_node, "linux,code",
219				     &pwrkey->code);
220	if (error) {
221		dev_dbg(&pdev->dev,
222			"no linux,code assuming power (%d)\n", error);
223		pwrkey->code = KEY_POWER;
224	}
225
226	pwrkey->input = devm_input_allocate_device(&pdev->dev);
227	if (!pwrkey->input) {
228		dev_dbg(&pdev->dev, "unable to allocate input device\n");
229		return -ENOMEM;
230	}
231
232	input_set_capability(pwrkey->input, EV_KEY, pwrkey->code);
233
234	pwrkey->input->name = "pm8941_pwrkey";
235	pwrkey->input->phys = "pm8941_pwrkey/input0";
236
237	req_delay = (req_delay << 6) / USEC_PER_SEC;
238	req_delay = ilog2(req_delay);
239
240	error = regmap_update_bits(pwrkey->regmap,
241				   pwrkey->baseaddr + PON_DBC_CTL,
242				   PON_DBC_DELAY_MASK,
243				   req_delay);
244	if (error) {
245		dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
246		return error;
247	}
248
249	error = regmap_update_bits(pwrkey->regmap,
250				   pwrkey->baseaddr + PON_PULL_CTL,
251				   pwrkey->data->pull_up_bit,
252				   pull_up ? pwrkey->data->pull_up_bit : 0);
253	if (error) {
254		dev_err(&pdev->dev, "failed to set pull: %d\n", error);
255		return error;
256	}
257
258	error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
259					  NULL, pm8941_pwrkey_irq,
260					  IRQF_ONESHOT,
261					  "pm8941_pwrkey", pwrkey);
262	if (error) {
263		dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
264		return error;
265	}
266
267	error = input_register_device(pwrkey->input);
268	if (error) {
269		dev_err(&pdev->dev, "failed to register input device: %d\n",
270			error);
271		return error;
272	}
273
274	pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,
275	error = register_reboot_notifier(&pwrkey->reboot_notifier);
276	if (error) {
277		dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
278			error);
279		return error;
280	}
281
282	platform_set_drvdata(pdev, pwrkey);
283	device_init_wakeup(&pdev->dev, 1);
284
285	return 0;
286}
287
288static int pm8941_pwrkey_remove(struct platform_device *pdev)
289{
290	struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
291
292	unregister_reboot_notifier(&pwrkey->reboot_notifier);
293
294	return 0;
295}
296
297static const struct pm8941_data pwrkey_data = {
298	.pull_up_bit = PON_KPDPWR_PULL_UP,
299	.status_bit = PON_KPDPWR_N_SET,
300};
301
302static const struct pm8941_data resin_data = {
303	.pull_up_bit = PON_RESIN_PULL_UP,
304	.status_bit = PON_RESIN_N_SET,
305};
306
307static const struct of_device_id pm8941_pwr_key_id_table[] = {
308	{ .compatible = "qcom,pm8941-pwrkey", .data = &pwrkey_data },
309	{ .compatible = "qcom,pm8941-resin", .data = &resin_data },
310	{ }
311};
312MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
313
314static struct platform_driver pm8941_pwrkey_driver = {
315	.probe = pm8941_pwrkey_probe,
316	.remove = pm8941_pwrkey_remove,
317	.driver = {
318		.name = "pm8941-pwrkey",
319		.pm = &pm8941_pwr_key_pm_ops,
320		.of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
321	},
322};
323module_platform_driver(pm8941_pwrkey_driver);
324
325MODULE_DESCRIPTION("PM8941 Power Key driver");
326MODULE_LICENSE("GPL v2");