1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Battery charger driver for TI's tps65090
4 *
5 * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
6
7 */
8#include <linux/delay.h>
9#include <linux/err.h>
10#include <linux/freezer.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/kernel.h>
14#include <linux/kthread.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/platform_device.h>
18#include <linux/power_supply.h>
19#include <linux/slab.h>
20
21#include <linux/mfd/tps65090.h>
22
23#define TPS65090_CHARGER_ENABLE	BIT(0)
24#define TPS65090_VACG		BIT(1)
25#define TPS65090_NOITERM	BIT(5)
26
27#define POLL_INTERVAL		(HZ * 2)	/* Used when no irq */
28
29struct tps65090_charger {
30	struct	device	*dev;
31	int	ac_online;
32	int	prev_ac_online;
33	int	irq;
34	struct task_struct	*poll_task;
35	bool			passive_mode;
36	struct power_supply	*ac;
37	struct tps65090_platform_data *pdata;
38};
39
40static enum power_supply_property tps65090_ac_props[] = {
41	POWER_SUPPLY_PROP_ONLINE,
42};
43
44static int tps65090_low_chrg_current(struct tps65090_charger *charger)
45{
46	int ret;
47
48	if (charger->passive_mode)
49		return 0;
50
51	ret = tps65090_write(charger->dev->parent, TPS65090_REG_CG_CTRL5,
52			TPS65090_NOITERM);
53	if (ret < 0) {
54		dev_err(charger->dev, "%s(): error reading in register 0x%x\n",
55			__func__, TPS65090_REG_CG_CTRL5);
56		return ret;
57	}
58	return 0;
59}
60
61static int tps65090_enable_charging(struct tps65090_charger *charger)
62{
63	int ret;
64	uint8_t ctrl0 = 0;
65
66	if (charger->passive_mode)
67		return 0;
68
69	ret = tps65090_read(charger->dev->parent, TPS65090_REG_CG_CTRL0,
70			    &ctrl0);
71	if (ret < 0) {
72		dev_err(charger->dev, "%s(): error reading in register 0x%x\n",
73				__func__, TPS65090_REG_CG_CTRL0);
74		return ret;
75	}
76
77	ret = tps65090_write(charger->dev->parent, TPS65090_REG_CG_CTRL0,
78				(ctrl0 | TPS65090_CHARGER_ENABLE));
79	if (ret < 0) {
80		dev_err(charger->dev, "%s(): error writing in register 0x%x\n",
81				__func__, TPS65090_REG_CG_CTRL0);
82		return ret;
83	}
84	return 0;
85}
86
87static int tps65090_config_charger(struct tps65090_charger *charger)
88{
89	uint8_t intrmask = 0;
90	int ret;
91
92	if (charger->passive_mode)
93		return 0;
94
95	if (charger->pdata->enable_low_current_chrg) {
96		ret = tps65090_low_chrg_current(charger);
97		if (ret < 0) {
98			dev_err(charger->dev,
99				"error configuring low charge current\n");
100			return ret;
101		}
102	}
103
104	/* Enable the VACG interrupt for AC power detect */
105	ret = tps65090_read(charger->dev->parent, TPS65090_REG_INTR_MASK,
106			    &intrmask);
107	if (ret < 0) {
108		dev_err(charger->dev, "%s(): error reading in register 0x%x\n",
109			__func__, TPS65090_REG_INTR_MASK);
110		return ret;
111	}
112
113	ret = tps65090_write(charger->dev->parent, TPS65090_REG_INTR_MASK,
114			     (intrmask | TPS65090_VACG));
115	if (ret < 0) {
116		dev_err(charger->dev, "%s(): error writing in register 0x%x\n",
117			__func__, TPS65090_REG_CG_CTRL0);
118		return ret;
119	}
120
121	return 0;
122}
123
124static int tps65090_ac_get_property(struct power_supply *psy,
125			enum power_supply_property psp,
126			union power_supply_propval *val)
127{
128	struct tps65090_charger *charger = power_supply_get_drvdata(psy);
129
130	if (psp == POWER_SUPPLY_PROP_ONLINE) {
131		val->intval = charger->ac_online;
132		charger->prev_ac_online = charger->ac_online;
133		return 0;
134	}
135	return -EINVAL;
136}
137
138static irqreturn_t tps65090_charger_isr(int irq, void *dev_id)
139{
140	struct tps65090_charger *charger = dev_id;
141	int ret;
142	uint8_t status1 = 0;
143	uint8_t intrsts = 0;
144
145	ret = tps65090_read(charger->dev->parent, TPS65090_REG_CG_STATUS1,
146			    &status1);
147	if (ret < 0) {
148		dev_err(charger->dev, "%s(): Error in reading reg 0x%x\n",
149				__func__, TPS65090_REG_CG_STATUS1);
150		return IRQ_HANDLED;
151	}
152	msleep(75);
153	ret = tps65090_read(charger->dev->parent, TPS65090_REG_INTR_STS,
154			    &intrsts);
155	if (ret < 0) {
156		dev_err(charger->dev, "%s(): Error in reading reg 0x%x\n",
157				__func__, TPS65090_REG_INTR_STS);
158		return IRQ_HANDLED;
159	}
160
161	if (intrsts & TPS65090_VACG) {
162		ret = tps65090_enable_charging(charger);
163		if (ret < 0)
164			return IRQ_HANDLED;
165		charger->ac_online = 1;
166	} else {
167		charger->ac_online = 0;
168	}
169
170	/* Clear interrupts. */
171	if (!charger->passive_mode) {
172		ret = tps65090_write(charger->dev->parent,
173				     TPS65090_REG_INTR_STS, 0x00);
174		if (ret < 0) {
175			dev_err(charger->dev,
176				"%s(): Error in writing reg 0x%x\n",
177				__func__, TPS65090_REG_INTR_STS);
178		}
179	}
180
181	if (charger->prev_ac_online != charger->ac_online)
182		power_supply_changed(charger->ac);
183
184	return IRQ_HANDLED;
185}
186
187static struct tps65090_platform_data *
188		tps65090_parse_dt_charger_data(struct platform_device *pdev)
189{
190	struct tps65090_platform_data *pdata;
191	struct device_node *np = pdev->dev.of_node;
192	unsigned int prop;
193
194	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
195	if (!pdata) {
196		dev_err(&pdev->dev, "Memory alloc for tps65090_pdata failed\n");
197		return NULL;
198	}
199
200	prop = of_property_read_bool(np, "ti,enable-low-current-chrg");
201	pdata->enable_low_current_chrg = prop;
202
203	pdata->irq_base = -1;
204
205	return pdata;
206
207}
208
209static int tps65090_charger_poll_task(void *data)
210{
211	set_freezable();
212
213	while (!kthread_should_stop()) {
214		schedule_timeout_interruptible(POLL_INTERVAL);
215		try_to_freeze();
216		tps65090_charger_isr(-1, data);
217	}
218	return 0;
219}
220
221static const struct power_supply_desc tps65090_charger_desc = {
222	.name			= "tps65090-ac",
223	.type			= POWER_SUPPLY_TYPE_MAINS,
224	.get_property		= tps65090_ac_get_property,
225	.properties		= tps65090_ac_props,
226	.num_properties		= ARRAY_SIZE(tps65090_ac_props),
227};
228
229static int tps65090_charger_probe(struct platform_device *pdev)
230{
231	struct tps65090_charger *cdata;
232	struct tps65090_platform_data *pdata;
233	struct power_supply_config psy_cfg = {};
234	uint8_t status1 = 0;
235	int ret;
236	int irq;
237
238	pdata = dev_get_platdata(pdev->dev.parent);
239
240	if (IS_ENABLED(CONFIG_OF) && !pdata && pdev->dev.of_node)
241		pdata = tps65090_parse_dt_charger_data(pdev);
242
243	if (!pdata) {
244		dev_err(&pdev->dev, "%s():no platform data available\n",
245				__func__);
246		return -ENODEV;
247	}
248
249	cdata = devm_kzalloc(&pdev->dev, sizeof(*cdata), GFP_KERNEL);
250	if (!cdata) {
251		dev_err(&pdev->dev, "failed to allocate memory status\n");
252		return -ENOMEM;
253	}
254
255	platform_set_drvdata(pdev, cdata);
256
257	cdata->dev			= &pdev->dev;
258	cdata->pdata			= pdata;
259
260	psy_cfg.supplied_to		= pdata->supplied_to;
261	psy_cfg.num_supplicants		= pdata->num_supplicants;
262	psy_cfg.of_node			= pdev->dev.of_node;
263	psy_cfg.drv_data		= cdata;
264
265	cdata->ac = devm_power_supply_register(&pdev->dev, &tps65090_charger_desc,
266			&psy_cfg);
267	if (IS_ERR(cdata->ac)) {
268		dev_err(&pdev->dev, "failed: power supply register\n");
269		return PTR_ERR(cdata->ac);
270	}
271
272	irq = platform_get_irq(pdev, 0);
273	if (irq < 0)
274		irq = -ENXIO;
275	cdata->irq = irq;
276
277	ret = tps65090_config_charger(cdata);
278	if (ret < 0) {
279		dev_err(&pdev->dev, "charger config failed, err %d\n", ret);
280		return ret;
281	}
282
283	/* Check for charger presence */
284	ret = tps65090_read(cdata->dev->parent, TPS65090_REG_CG_STATUS1,
285			&status1);
286	if (ret < 0) {
287		dev_err(cdata->dev, "%s(): Error in reading reg 0x%x", __func__,
288			TPS65090_REG_CG_STATUS1);
289		return ret;
290	}
291
292	if (status1 != 0) {
293		ret = tps65090_enable_charging(cdata);
294		if (ret < 0) {
295			dev_err(cdata->dev, "error enabling charger\n");
296			return ret;
297		}
298		cdata->ac_online = 1;
299		power_supply_changed(cdata->ac);
300	}
301
302	if (irq != -ENXIO) {
303		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
304			tps65090_charger_isr, IRQF_ONESHOT, "tps65090-charger", cdata);
305		if (ret) {
306			dev_err(cdata->dev,
307				"Unable to register irq %d err %d\n", irq,
308				ret);
309			return ret;
310		}
311	} else {
312		cdata->poll_task = kthread_run(tps65090_charger_poll_task,
313					      cdata, "ktps65090charger");
314		cdata->passive_mode = true;
315		if (IS_ERR(cdata->poll_task)) {
316			ret = PTR_ERR(cdata->poll_task);
317			dev_err(cdata->dev,
318				"Unable to run kthread err %d\n", ret);
319			return ret;
320		}
321	}
322
323	return 0;
324}
325
326static void tps65090_charger_remove(struct platform_device *pdev)
327{
328	struct tps65090_charger *cdata = platform_get_drvdata(pdev);
329
330	if (cdata->irq == -ENXIO)
331		kthread_stop(cdata->poll_task);
332}
333
334static const struct of_device_id of_tps65090_charger_match[] = {
335	{ .compatible = "ti,tps65090-charger", },
336	{ /* end */ }
337};
338MODULE_DEVICE_TABLE(of, of_tps65090_charger_match);
339
340static struct platform_driver tps65090_charger_driver = {
341	.driver	= {
342		.name	= "tps65090-charger",
343		.of_match_table = of_tps65090_charger_match,
344	},
345	.probe	= tps65090_charger_probe,
346	.remove_new = tps65090_charger_remove,
347};
348module_platform_driver(tps65090_charger_driver);
349
350MODULE_LICENSE("GPL v2");
351MODULE_AUTHOR("Syed Rafiuddin <srafiuddin@nvidia.com>");
352MODULE_DESCRIPTION("tps65090 battery charger driver");
353