xref: /openbmc/linux/drivers/mfd/atc260x-core.c (revision f3531d1a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Core support for ATC260x PMICs
4  *
5  * Copyright (C) 2019 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
6  * Copyright (C) 2020 Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
7  */
8 
9 #include <linux/interrupt.h>
10 #include <linux/mfd/atc260x/core.h>
11 #include <linux/mfd/core.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/regmap.h>
16 
17 #define ATC260X_CHIP_REV_MAX	31
18 
19 struct atc260x_init_regs {
20 	unsigned int cmu_devrst;
21 	unsigned int cmu_devrst_ints;
22 	unsigned int ints_msk;
23 	unsigned int pad_en;
24 	unsigned int pad_en_extirq;
25 };
26 
27 static void regmap_lock_mutex(void *__mutex)
28 {
29 	struct mutex *mutex = __mutex;
30 
31 	/*
32 	 * Using regmap within an atomic context (e.g. accessing a PMIC when
33 	 * powering system down) is normally allowed only if the regmap type
34 	 * is MMIO and the regcache type is either REGCACHE_NONE or
35 	 * REGCACHE_FLAT. For slow buses like I2C and SPI, the regmap is
36 	 * internally protected by a mutex which is acquired non-atomically.
37 	 *
38 	 * Let's improve this by using a customized locking scheme inspired
39 	 * from I2C atomic transfer. See i2c_in_atomic_xfer_mode() for a
40 	 * starting point.
41 	 */
42 	if (system_state > SYSTEM_RUNNING && irqs_disabled())
43 		mutex_trylock(mutex);
44 	else
45 		mutex_lock(mutex);
46 }
47 
48 static void regmap_unlock_mutex(void *__mutex)
49 {
50 	struct mutex *mutex = __mutex;
51 
52 	mutex_unlock(mutex);
53 }
54 
55 static const struct regmap_config atc2603c_regmap_config = {
56 	.reg_bits = 8,
57 	.val_bits = 16,
58 	.max_register = ATC2603C_SADDR,
59 	.cache_type = REGCACHE_NONE,
60 };
61 
62 static const struct regmap_config atc2609a_regmap_config = {
63 	.reg_bits = 8,
64 	.val_bits = 16,
65 	.max_register = ATC2609A_SADDR,
66 	.cache_type = REGCACHE_NONE,
67 };
68 
69 static const struct regmap_irq atc2603c_regmap_irqs[] = {
70 	REGMAP_IRQ_REG(ATC2603C_IRQ_AUDIO,	0, ATC2603C_INTS_MSK_AUDIO),
71 	REGMAP_IRQ_REG(ATC2603C_IRQ_OV,		0, ATC2603C_INTS_MSK_OV),
72 	REGMAP_IRQ_REG(ATC2603C_IRQ_OC,		0, ATC2603C_INTS_MSK_OC),
73 	REGMAP_IRQ_REG(ATC2603C_IRQ_OT,		0, ATC2603C_INTS_MSK_OT),
74 	REGMAP_IRQ_REG(ATC2603C_IRQ_UV,		0, ATC2603C_INTS_MSK_UV),
75 	REGMAP_IRQ_REG(ATC2603C_IRQ_ALARM,	0, ATC2603C_INTS_MSK_ALARM),
76 	REGMAP_IRQ_REG(ATC2603C_IRQ_ONOFF,	0, ATC2603C_INTS_MSK_ONOFF),
77 	REGMAP_IRQ_REG(ATC2603C_IRQ_SGPIO,	0, ATC2603C_INTS_MSK_SGPIO),
78 	REGMAP_IRQ_REG(ATC2603C_IRQ_IR,		0, ATC2603C_INTS_MSK_IR),
79 	REGMAP_IRQ_REG(ATC2603C_IRQ_REMCON,	0, ATC2603C_INTS_MSK_REMCON),
80 	REGMAP_IRQ_REG(ATC2603C_IRQ_POWER_IN,	0, ATC2603C_INTS_MSK_POWERIN),
81 };
82 
83 static const struct regmap_irq atc2609a_regmap_irqs[] = {
84 	REGMAP_IRQ_REG(ATC2609A_IRQ_AUDIO,	0, ATC2609A_INTS_MSK_AUDIO),
85 	REGMAP_IRQ_REG(ATC2609A_IRQ_OV,		0, ATC2609A_INTS_MSK_OV),
86 	REGMAP_IRQ_REG(ATC2609A_IRQ_OC,		0, ATC2609A_INTS_MSK_OC),
87 	REGMAP_IRQ_REG(ATC2609A_IRQ_OT,		0, ATC2609A_INTS_MSK_OT),
88 	REGMAP_IRQ_REG(ATC2609A_IRQ_UV,		0, ATC2609A_INTS_MSK_UV),
89 	REGMAP_IRQ_REG(ATC2609A_IRQ_ALARM,	0, ATC2609A_INTS_MSK_ALARM),
90 	REGMAP_IRQ_REG(ATC2609A_IRQ_ONOFF,	0, ATC2609A_INTS_MSK_ONOFF),
91 	REGMAP_IRQ_REG(ATC2609A_IRQ_WKUP,	0, ATC2609A_INTS_MSK_WKUP),
92 	REGMAP_IRQ_REG(ATC2609A_IRQ_IR,		0, ATC2609A_INTS_MSK_IR),
93 	REGMAP_IRQ_REG(ATC2609A_IRQ_REMCON,	0, ATC2609A_INTS_MSK_REMCON),
94 	REGMAP_IRQ_REG(ATC2609A_IRQ_POWER_IN,	0, ATC2609A_INTS_MSK_POWERIN),
95 };
96 
97 static const struct regmap_irq_chip atc2603c_regmap_irq_chip = {
98 	.name = "atc2603c",
99 	.irqs = atc2603c_regmap_irqs,
100 	.num_irqs = ARRAY_SIZE(atc2603c_regmap_irqs),
101 	.num_regs = 1,
102 	.status_base = ATC2603C_INTS_PD,
103 	.unmask_base = ATC2603C_INTS_MSK,
104 };
105 
106 static const struct regmap_irq_chip atc2609a_regmap_irq_chip = {
107 	.name = "atc2609a",
108 	.irqs = atc2609a_regmap_irqs,
109 	.num_irqs = ARRAY_SIZE(atc2609a_regmap_irqs),
110 	.num_regs = 1,
111 	.status_base = ATC2609A_INTS_PD,
112 	.unmask_base = ATC2609A_INTS_MSK,
113 };
114 
115 static const struct resource atc2603c_onkey_resources[] = {
116 	DEFINE_RES_IRQ(ATC2603C_IRQ_ONOFF),
117 };
118 
119 static const struct resource atc2609a_onkey_resources[] = {
120 	DEFINE_RES_IRQ(ATC2609A_IRQ_ONOFF),
121 };
122 
123 static const struct mfd_cell atc2603c_mfd_cells[] = {
124 	{ .name = "atc260x-regulator" },
125 	{ .name = "atc260x-pwrc" },
126 	{
127 		.name = "atc260x-onkey",
128 		.num_resources = ARRAY_SIZE(atc2603c_onkey_resources),
129 		.resources = atc2603c_onkey_resources,
130 	},
131 };
132 
133 static const struct mfd_cell atc2609a_mfd_cells[] = {
134 	{ .name = "atc260x-regulator" },
135 	{ .name = "atc260x-pwrc" },
136 	{
137 		.name = "atc260x-onkey",
138 		.num_resources = ARRAY_SIZE(atc2609a_onkey_resources),
139 		.resources = atc2609a_onkey_resources,
140 	},
141 };
142 
143 static const struct atc260x_init_regs atc2603c_init_regs = {
144 	.cmu_devrst = ATC2603C_CMU_DEVRST,
145 	.cmu_devrst_ints = ATC2603C_CMU_DEVRST_INTS,
146 	.ints_msk = ATC2603C_INTS_MSK,
147 	.pad_en = ATC2603C_PAD_EN,
148 	.pad_en_extirq = ATC2603C_PAD_EN_EXTIRQ,
149 };
150 
151 static const struct atc260x_init_regs atc2609a_init_regs = {
152 	.cmu_devrst = ATC2609A_CMU_DEVRST,
153 	.cmu_devrst_ints = ATC2609A_CMU_DEVRST_INTS,
154 	.ints_msk = ATC2609A_INTS_MSK,
155 	.pad_en = ATC2609A_PAD_EN,
156 	.pad_en_extirq = ATC2609A_PAD_EN_EXTIRQ,
157 };
158 
159 static void atc260x_cmu_reset(struct atc260x *atc260x)
160 {
161 	const struct atc260x_init_regs *regs = atc260x->init_regs;
162 
163 	/* Assert reset */
164 	regmap_update_bits(atc260x->regmap, regs->cmu_devrst,
165 			   regs->cmu_devrst_ints, ~regs->cmu_devrst_ints);
166 
167 	/* De-assert reset */
168 	regmap_update_bits(atc260x->regmap, regs->cmu_devrst,
169 			   regs->cmu_devrst_ints, regs->cmu_devrst_ints);
170 }
171 
172 static void atc260x_dev_init(struct atc260x *atc260x)
173 {
174 	const struct atc260x_init_regs *regs = atc260x->init_regs;
175 
176 	/* Initialize interrupt block */
177 	atc260x_cmu_reset(atc260x);
178 
179 	/* Disable all interrupt sources */
180 	regmap_write(atc260x->regmap, regs->ints_msk, 0);
181 
182 	/* Enable EXTIRQ pad */
183 	regmap_update_bits(atc260x->regmap, regs->pad_en,
184 			   regs->pad_en_extirq, regs->pad_en_extirq);
185 }
186 
187 /**
188  * atc260x_match_device(): Setup ATC260x variant related fields
189  *
190  * @atc260x: ATC260x device to setup (.dev field must be set)
191  * @regmap_cfg: regmap config associated with this ATC260x device
192  *
193  * This lets the ATC260x core configure the MFD cells and register maps
194  * for later use.
195  */
196 int atc260x_match_device(struct atc260x *atc260x, struct regmap_config *regmap_cfg)
197 {
198 	struct device *dev = atc260x->dev;
199 	const void *of_data;
200 
201 	of_data = of_device_get_match_data(dev);
202 	if (!of_data)
203 		return -ENODEV;
204 
205 	atc260x->ic_type = (unsigned long)of_data;
206 
207 	switch (atc260x->ic_type) {
208 	case ATC2603C:
209 		*regmap_cfg = atc2603c_regmap_config;
210 		atc260x->regmap_irq_chip = &atc2603c_regmap_irq_chip;
211 		atc260x->cells = atc2603c_mfd_cells;
212 		atc260x->nr_cells = ARRAY_SIZE(atc2603c_mfd_cells);
213 		atc260x->type_name = "atc2603c";
214 		atc260x->rev_reg = ATC2603C_CHIP_VER;
215 		atc260x->init_regs = &atc2603c_init_regs;
216 		break;
217 	case ATC2609A:
218 		*regmap_cfg = atc2609a_regmap_config;
219 		atc260x->regmap_irq_chip = &atc2609a_regmap_irq_chip;
220 		atc260x->cells = atc2609a_mfd_cells;
221 		atc260x->nr_cells = ARRAY_SIZE(atc2609a_mfd_cells);
222 		atc260x->type_name = "atc2609a";
223 		atc260x->rev_reg = ATC2609A_CHIP_VER;
224 		atc260x->init_regs = &atc2609a_init_regs;
225 		break;
226 	default:
227 		dev_err(dev, "Unsupported ATC260x device type: %u\n",
228 			atc260x->ic_type);
229 		return -EINVAL;
230 	}
231 
232 	atc260x->regmap_mutex = devm_kzalloc(dev, sizeof(*atc260x->regmap_mutex),
233 					     GFP_KERNEL);
234 	if (!atc260x->regmap_mutex)
235 		return -ENOMEM;
236 
237 	mutex_init(atc260x->regmap_mutex);
238 
239 	regmap_cfg->lock = regmap_lock_mutex,
240 	regmap_cfg->unlock = regmap_unlock_mutex,
241 	regmap_cfg->lock_arg = atc260x->regmap_mutex;
242 
243 	return 0;
244 }
245 EXPORT_SYMBOL_GPL(atc260x_match_device);
246 
247 /**
248  * atc260x_device_probe(): Probe a configured ATC260x device
249  *
250  * @atc260x: ATC260x device to probe (must be configured)
251  *
252  * This function lets the ATC260x core register the ATC260x MFD devices
253  * and IRQCHIP. The ATC260x device passed in must be fully configured
254  * with atc260x_match_device, its IRQ set, and regmap created.
255  */
256 int atc260x_device_probe(struct atc260x *atc260x)
257 {
258 	struct device *dev = atc260x->dev;
259 	unsigned int chip_rev;
260 	int ret;
261 
262 	if (!atc260x->irq) {
263 		dev_err(dev, "No interrupt support\n");
264 		return -EINVAL;
265 	}
266 
267 	/* Initialize the hardware */
268 	atc260x_dev_init(atc260x);
269 
270 	ret = regmap_read(atc260x->regmap, atc260x->rev_reg, &chip_rev);
271 	if (ret) {
272 		dev_err(dev, "Failed to get chip revision\n");
273 		return ret;
274 	}
275 
276 	if (chip_rev > ATC260X_CHIP_REV_MAX) {
277 		dev_err(dev, "Unknown chip revision: %u\n", chip_rev);
278 		return -EINVAL;
279 	}
280 
281 	atc260x->ic_ver = __ffs(chip_rev + 1U);
282 
283 	dev_info(dev, "Detected chip type %s rev.%c\n",
284 		 atc260x->type_name, 'A' + atc260x->ic_ver);
285 
286 	ret = devm_regmap_add_irq_chip(dev, atc260x->regmap, atc260x->irq, IRQF_ONESHOT,
287 				       -1, atc260x->regmap_irq_chip, &atc260x->irq_data);
288 	if (ret) {
289 		dev_err(dev, "Failed to add IRQ chip: %d\n", ret);
290 		return ret;
291 	}
292 
293 	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
294 				   atc260x->cells, atc260x->nr_cells, NULL, 0,
295 				   regmap_irq_get_domain(atc260x->irq_data));
296 	if (ret) {
297 		dev_err(dev, "Failed to add child devices: %d\n", ret);
298 		regmap_del_irq_chip(atc260x->irq, atc260x->irq_data);
299 	}
300 
301 	return ret;
302 }
303 EXPORT_SYMBOL_GPL(atc260x_device_probe);
304 
305 MODULE_DESCRIPTION("ATC260x PMICs Core support");
306 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
307 MODULE_AUTHOR("Cristian Ciocaltea <cristian.ciocaltea@gmail.com>");
308 MODULE_LICENSE("GPL");
309