xref: /linux/drivers/mfd/rohm-bd96801.c (revision b8e4b0529d59a3ccd0b25a31d3cfc8b0f3b34068)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2024 ROHM Semiconductors
4  *
5  * ROHM BD96801 PMIC driver
6  *
7  * This version of the "BD86801 scalable PMIC"'s driver supports only very
8  * basic set of the PMIC features. Most notably, there is no support for
9  * the ERRB interrupt and the configurations which should be done when the
10  * PMIC is in STBY mode.
11  *
12  * Supporting the ERRB interrupt would require dropping the regmap-IRQ
13  * usage or working around (or accepting a presense of) a naming conflict
14  * in debugFS IRQs.
15  *
16  * Being able to reliably do the configurations like changing the
17  * regulator safety limits (like limits for the over/under -voltages, over
18  * current, thermal protection) would require the configuring driver to be
19  * synchronized with entity causing the PMIC state transitions. Eg, one
20  * should be able to ensure the PMIC is in STBY state when the
21  * configurations are applied to the hardware. How and when the PMIC state
22  * transitions are to be done is likely to be very system specific, as will
23  * be the need to configure these safety limits. Hence it's not simple to
24  * come up with a generic solution.
25  *
26  * Users who require the ERRB handling and STBY state configurations can
27  * have a look at the original RFC:
28  * https://lore.kernel.org/all/cover.1712920132.git.mazziesaccount@gmail.com/
29  * which implements a workaround to debugFS naming conflict and some of
30  * the safety limit configurations - but leaves the state change handling
31  * and synchronization to be implemented.
32  *
33  * It would be great to hear (and receive a patch!) if you implement the
34  * STBY configuration support or a proper fix to the debugFS naming
35  * conflict in your downstream driver ;)
36  */
37 
38 #include <linux/i2c.h>
39 #include <linux/interrupt.h>
40 #include <linux/mfd/core.h>
41 #include <linux/module.h>
42 #include <linux/property.h>
43 #include <linux/regmap.h>
44 #include <linux/types.h>
45 
46 #include <linux/mfd/rohm-bd96801.h>
47 #include <linux/mfd/rohm-generic.h>
48 
49 static const struct resource regulator_intb_irqs[] = {
50 	DEFINE_RES_IRQ_NAMED(BD96801_TW_STAT, "bd96801-core-thermal"),
51 
52 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_OCPH_STAT, "bd96801-buck1-overcurr-h"),
53 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_OCPL_STAT, "bd96801-buck1-overcurr-l"),
54 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_OCPN_STAT, "bd96801-buck1-overcurr-n"),
55 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_OVD_STAT, "bd96801-buck1-overvolt"),
56 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_UVD_STAT, "bd96801-buck1-undervolt"),
57 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK1_TW_CH_STAT, "bd96801-buck1-thermal"),
58 
59 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_OCPH_STAT, "bd96801-buck2-overcurr-h"),
60 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_OCPL_STAT, "bd96801-buck2-overcurr-l"),
61 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_OCPN_STAT, "bd96801-buck2-overcurr-n"),
62 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_OVD_STAT, "bd96801-buck2-overvolt"),
63 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_UVD_STAT, "bd96801-buck2-undervolt"),
64 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK2_TW_CH_STAT, "bd96801-buck2-thermal"),
65 
66 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_OCPH_STAT, "bd96801-buck3-overcurr-h"),
67 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_OCPL_STAT, "bd96801-buck3-overcurr-l"),
68 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_OCPN_STAT, "bd96801-buck3-overcurr-n"),
69 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_OVD_STAT, "bd96801-buck3-overvolt"),
70 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_UVD_STAT, "bd96801-buck3-undervolt"),
71 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK3_TW_CH_STAT, "bd96801-buck3-thermal"),
72 
73 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_OCPH_STAT, "bd96801-buck4-overcurr-h"),
74 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_OCPL_STAT, "bd96801-buck4-overcurr-l"),
75 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_OCPN_STAT, "bd96801-buck4-overcurr-n"),
76 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_OVD_STAT, "bd96801-buck4-overvolt"),
77 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_UVD_STAT, "bd96801-buck4-undervolt"),
78 	DEFINE_RES_IRQ_NAMED(BD96801_BUCK4_TW_CH_STAT, "bd96801-buck4-thermal"),
79 
80 	DEFINE_RES_IRQ_NAMED(BD96801_LDO5_OCPH_STAT, "bd96801-ldo5-overcurr"),
81 	DEFINE_RES_IRQ_NAMED(BD96801_LDO5_OVD_STAT, "bd96801-ldo5-overvolt"),
82 	DEFINE_RES_IRQ_NAMED(BD96801_LDO5_UVD_STAT, "bd96801-ldo5-undervolt"),
83 
84 	DEFINE_RES_IRQ_NAMED(BD96801_LDO6_OCPH_STAT, "bd96801-ldo6-overcurr"),
85 	DEFINE_RES_IRQ_NAMED(BD96801_LDO6_OVD_STAT, "bd96801-ldo6-overvolt"),
86 	DEFINE_RES_IRQ_NAMED(BD96801_LDO6_UVD_STAT, "bd96801-ldo6-undervolt"),
87 
88 	DEFINE_RES_IRQ_NAMED(BD96801_LDO7_OCPH_STAT, "bd96801-ldo7-overcurr"),
89 	DEFINE_RES_IRQ_NAMED(BD96801_LDO7_OVD_STAT, "bd96801-ldo7-overvolt"),
90 	DEFINE_RES_IRQ_NAMED(BD96801_LDO7_UVD_STAT, "bd96801-ldo7-undervolt"),
91 };
92 
93 static const struct resource wdg_intb_irqs[] = {
94 	DEFINE_RES_IRQ_NAMED(BD96801_WDT_ERR_STAT, "bd96801-wdg"),
95 };
96 
97 static struct mfd_cell bd96801_cells[] = {
98 	{
99 		.name = "bd96801-wdt",
100 		.resources = wdg_intb_irqs,
101 		.num_resources = ARRAY_SIZE(wdg_intb_irqs),
102 	}, {
103 		.name = "bd96801-regulator",
104 		.resources = regulator_intb_irqs,
105 		.num_resources = ARRAY_SIZE(regulator_intb_irqs),
106 	},
107 };
108 
109 static const struct regmap_range bd96801_volatile_ranges[] = {
110 	/* Status registers */
111 	regmap_reg_range(BD96801_REG_WD_FEED, BD96801_REG_WD_FAILCOUNT),
112 	regmap_reg_range(BD96801_REG_WD_ASK, BD96801_REG_WD_ASK),
113 	regmap_reg_range(BD96801_REG_WD_STATUS, BD96801_REG_WD_STATUS),
114 	regmap_reg_range(BD96801_REG_PMIC_STATE, BD96801_REG_INT_LDO7_INTB),
115 	/* Registers which do not update value unless PMIC is in STBY */
116 	regmap_reg_range(BD96801_REG_SSCG_CTRL, BD96801_REG_SHD_INTB),
117 	regmap_reg_range(BD96801_REG_BUCK_OVP, BD96801_REG_BOOT_OVERTIME),
118 	/*
119 	 * LDO control registers have single bit (LDO MODE) which does not
120 	 * change when we write it unless PMIC is in STBY. It's safer to not
121 	 * cache it.
122 	 */
123 	regmap_reg_range(BD96801_LDO5_VOL_LVL_REG, BD96801_LDO7_VOL_LVL_REG),
124 };
125 
126 static const struct regmap_access_table volatile_regs = {
127 	.yes_ranges = bd96801_volatile_ranges,
128 	.n_yes_ranges = ARRAY_SIZE(bd96801_volatile_ranges),
129 };
130 
131 static const struct regmap_irq bd96801_intb_irqs[] = {
132 	/* STATUS SYSTEM INTB */
133 	REGMAP_IRQ_REG(BD96801_TW_STAT, 0, BD96801_TW_STAT_MASK),
134 	REGMAP_IRQ_REG(BD96801_WDT_ERR_STAT, 0, BD96801_WDT_ERR_STAT_MASK),
135 	REGMAP_IRQ_REG(BD96801_I2C_ERR_STAT, 0, BD96801_I2C_ERR_STAT_MASK),
136 	REGMAP_IRQ_REG(BD96801_CHIP_IF_ERR_STAT, 0, BD96801_CHIP_IF_ERR_STAT_MASK),
137 	/* STATUS BUCK1 INTB */
138 	REGMAP_IRQ_REG(BD96801_BUCK1_OCPH_STAT, 1, BD96801_BUCK_OCPH_STAT_MASK),
139 	REGMAP_IRQ_REG(BD96801_BUCK1_OCPL_STAT, 1, BD96801_BUCK_OCPL_STAT_MASK),
140 	REGMAP_IRQ_REG(BD96801_BUCK1_OCPN_STAT, 1, BD96801_BUCK_OCPN_STAT_MASK),
141 	REGMAP_IRQ_REG(BD96801_BUCK1_OVD_STAT, 1, BD96801_BUCK_OVD_STAT_MASK),
142 	REGMAP_IRQ_REG(BD96801_BUCK1_UVD_STAT, 1, BD96801_BUCK_UVD_STAT_MASK),
143 	REGMAP_IRQ_REG(BD96801_BUCK1_TW_CH_STAT, 1, BD96801_BUCK_TW_CH_STAT_MASK),
144 	/* BUCK 2 INTB */
145 	REGMAP_IRQ_REG(BD96801_BUCK2_OCPH_STAT, 2, BD96801_BUCK_OCPH_STAT_MASK),
146 	REGMAP_IRQ_REG(BD96801_BUCK2_OCPL_STAT, 2, BD96801_BUCK_OCPL_STAT_MASK),
147 	REGMAP_IRQ_REG(BD96801_BUCK2_OCPN_STAT, 2, BD96801_BUCK_OCPN_STAT_MASK),
148 	REGMAP_IRQ_REG(BD96801_BUCK2_OVD_STAT, 2, BD96801_BUCK_OVD_STAT_MASK),
149 	REGMAP_IRQ_REG(BD96801_BUCK2_UVD_STAT, 2, BD96801_BUCK_UVD_STAT_MASK),
150 	REGMAP_IRQ_REG(BD96801_BUCK2_TW_CH_STAT, 2, BD96801_BUCK_TW_CH_STAT_MASK),
151 	/* BUCK 3 INTB */
152 	REGMAP_IRQ_REG(BD96801_BUCK3_OCPH_STAT, 3, BD96801_BUCK_OCPH_STAT_MASK),
153 	REGMAP_IRQ_REG(BD96801_BUCK3_OCPL_STAT, 3, BD96801_BUCK_OCPL_STAT_MASK),
154 	REGMAP_IRQ_REG(BD96801_BUCK3_OCPN_STAT, 3, BD96801_BUCK_OCPN_STAT_MASK),
155 	REGMAP_IRQ_REG(BD96801_BUCK3_OVD_STAT, 3, BD96801_BUCK_OVD_STAT_MASK),
156 	REGMAP_IRQ_REG(BD96801_BUCK3_UVD_STAT, 3, BD96801_BUCK_UVD_STAT_MASK),
157 	REGMAP_IRQ_REG(BD96801_BUCK3_TW_CH_STAT, 3, BD96801_BUCK_TW_CH_STAT_MASK),
158 	/* BUCK 4 INTB */
159 	REGMAP_IRQ_REG(BD96801_BUCK4_OCPH_STAT, 4, BD96801_BUCK_OCPH_STAT_MASK),
160 	REGMAP_IRQ_REG(BD96801_BUCK4_OCPL_STAT, 4, BD96801_BUCK_OCPL_STAT_MASK),
161 	REGMAP_IRQ_REG(BD96801_BUCK4_OCPN_STAT, 4, BD96801_BUCK_OCPN_STAT_MASK),
162 	REGMAP_IRQ_REG(BD96801_BUCK4_OVD_STAT, 4, BD96801_BUCK_OVD_STAT_MASK),
163 	REGMAP_IRQ_REG(BD96801_BUCK4_UVD_STAT, 4, BD96801_BUCK_UVD_STAT_MASK),
164 	REGMAP_IRQ_REG(BD96801_BUCK4_TW_CH_STAT, 4, BD96801_BUCK_TW_CH_STAT_MASK),
165 	/* LDO5 INTB */
166 	REGMAP_IRQ_REG(BD96801_LDO5_OCPH_STAT, 5, BD96801_LDO_OCPH_STAT_MASK),
167 	REGMAP_IRQ_REG(BD96801_LDO5_OVD_STAT, 5, BD96801_LDO_OVD_STAT_MASK),
168 	REGMAP_IRQ_REG(BD96801_LDO5_UVD_STAT, 5, BD96801_LDO_UVD_STAT_MASK),
169 	/* LDO6 INTB */
170 	REGMAP_IRQ_REG(BD96801_LDO6_OCPH_STAT, 6, BD96801_LDO_OCPH_STAT_MASK),
171 	REGMAP_IRQ_REG(BD96801_LDO6_OVD_STAT, 6, BD96801_LDO_OVD_STAT_MASK),
172 	REGMAP_IRQ_REG(BD96801_LDO6_UVD_STAT, 6, BD96801_LDO_UVD_STAT_MASK),
173 	/* LDO7 INTB */
174 	REGMAP_IRQ_REG(BD96801_LDO7_OCPH_STAT, 7, BD96801_LDO_OCPH_STAT_MASK),
175 	REGMAP_IRQ_REG(BD96801_LDO7_OVD_STAT, 7, BD96801_LDO_OVD_STAT_MASK),
176 	REGMAP_IRQ_REG(BD96801_LDO7_UVD_STAT, 7, BD96801_LDO_UVD_STAT_MASK),
177 };
178 
179 static struct regmap_irq_chip bd96801_irq_chip_intb = {
180 	.name = "bd96801-irq-intb",
181 	.main_status = BD96801_REG_INT_MAIN,
182 	.num_main_regs = 1,
183 	.irqs = &bd96801_intb_irqs[0],
184 	.num_irqs = ARRAY_SIZE(bd96801_intb_irqs),
185 	.status_base = BD96801_REG_INT_SYS_INTB,
186 	.mask_base = BD96801_REG_MASK_SYS_INTB,
187 	.ack_base = BD96801_REG_INT_SYS_INTB,
188 	.init_ack_masked = true,
189 	.num_regs = 8,
190 	.irq_reg_stride = 1,
191 };
192 
193 static const struct regmap_config bd96801_regmap_config = {
194 	.reg_bits = 8,
195 	.val_bits = 8,
196 	.volatile_table = &volatile_regs,
197 	.cache_type = REGCACHE_RBTREE,
198 };
199 
200 static int bd96801_i2c_probe(struct i2c_client *i2c)
201 {
202 	struct regmap_irq_chip_data *intb_irq_data;
203 	const struct fwnode_handle *fwnode;
204 	struct irq_domain *intb_domain;
205 	struct regmap *regmap;
206 	int ret, intb_irq;
207 
208 	fwnode = dev_fwnode(&i2c->dev);
209 	if (!fwnode)
210 		return dev_err_probe(&i2c->dev, -EINVAL, "Failed to find fwnode\n");
211 
212 	intb_irq = fwnode_irq_get_byname(fwnode, "intb");
213 	if (intb_irq < 0)
214 		return dev_err_probe(&i2c->dev, intb_irq, "INTB IRQ not configured\n");
215 
216 	regmap = devm_regmap_init_i2c(i2c, &bd96801_regmap_config);
217 	if (IS_ERR(regmap))
218 		return dev_err_probe(&i2c->dev, PTR_ERR(regmap),
219 				    "Regmap initialization failed\n");
220 
221 	ret = regmap_write(regmap, BD96801_LOCK_REG, BD96801_UNLOCK);
222 	if (ret)
223 		return dev_err_probe(&i2c->dev, ret, "Failed to unlock PMIC\n");
224 
225 	ret = devm_regmap_add_irq_chip(&i2c->dev, regmap, intb_irq,
226 				       IRQF_ONESHOT, 0, &bd96801_irq_chip_intb,
227 				       &intb_irq_data);
228 	if (ret)
229 		return dev_err_probe(&i2c->dev, ret, "Failed to add INTB IRQ chip\n");
230 
231 	intb_domain = regmap_irq_get_domain(intb_irq_data);
232 
233 	ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO,
234 				   bd96801_cells,
235 				   ARRAY_SIZE(bd96801_cells), NULL, 0,
236 				   intb_domain);
237 	if (ret)
238 		dev_err(&i2c->dev, "Failed to create subdevices\n");
239 
240 	return ret;
241 }
242 
243 static const struct of_device_id bd96801_of_match[] = {
244 	{ .compatible = "rohm,bd96801",	},
245 	{ }
246 };
247 MODULE_DEVICE_TABLE(of, bd96801_of_match);
248 
249 static struct i2c_driver bd96801_i2c_driver = {
250 	.driver = {
251 		.name = "rohm-bd96801",
252 		.of_match_table = bd96801_of_match,
253 	},
254 	.probe = bd96801_i2c_probe,
255 };
256 
257 static int __init bd96801_i2c_init(void)
258 {
259 	return i2c_add_driver(&bd96801_i2c_driver);
260 }
261 
262 /* Initialise early so consumer devices can complete system boot */
263 subsys_initcall(bd96801_i2c_init);
264 
265 static void __exit bd96801_i2c_exit(void)
266 {
267 	i2c_del_driver(&bd96801_i2c_driver);
268 }
269 module_exit(bd96801_i2c_exit);
270 
271 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
272 MODULE_DESCRIPTION("ROHM BD96801 Power Management IC driver");
273 MODULE_LICENSE("GPL");
274