xref: /openbmc/linux/drivers/mfd/rohm-bd9576.c (revision 9aa2cba7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2021 ROHM Semiconductors
4  *
5  * ROHM BD9576MUF and BD9573MUF PMIC driver
6  */
7 
8 #include <linux/i2c.h>
9 #include <linux/interrupt.h>
10 #include <linux/ioport.h>
11 #include <linux/irq.h>
12 #include <linux/mfd/core.h>
13 #include <linux/mfd/rohm-bd957x.h>
14 #include <linux/mfd/rohm-generic.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/regmap.h>
18 #include <linux/types.h>
19 
20 enum {
21 	BD957X_REGULATOR_CELL,
22 	BD957X_WDT_CELL,
23 };
24 
25 /*
26  * Due to the BD9576MUF nasty IRQ behaviour we don't always populate IRQs.
27  * These will be added to regulator resources only if IRQ information for the
28  * PMIC is populated in device-tree.
29  */
30 static const struct resource bd9576_regulator_irqs[] = {
31 	DEFINE_RES_IRQ_NAMED(BD9576_INT_THERM, "bd9576-temp"),
32 	DEFINE_RES_IRQ_NAMED(BD9576_INT_OVD, "bd9576-ovd"),
33 	DEFINE_RES_IRQ_NAMED(BD9576_INT_UVD, "bd9576-uvd"),
34 };
35 
36 static struct mfd_cell bd9573_mfd_cells[] = {
37 	[BD957X_REGULATOR_CELL]	= { .name = "bd9573-regulator", },
38 	[BD957X_WDT_CELL]	= { .name = "bd9576-wdt", },
39 };
40 
41 static struct mfd_cell bd9576_mfd_cells[] = {
42 	[BD957X_REGULATOR_CELL]	= { .name = "bd9576-regulator", },
43 	[BD957X_WDT_CELL]	= { .name = "bd9576-wdt", },
44 };
45 
46 static const struct regmap_range volatile_ranges[] = {
47 	regmap_reg_range(BD957X_REG_SMRB_ASSERT, BD957X_REG_SMRB_ASSERT),
48 	regmap_reg_range(BD957X_REG_PMIC_INTERNAL_STAT,
49 			 BD957X_REG_PMIC_INTERNAL_STAT),
50 	regmap_reg_range(BD957X_REG_INT_THERM_STAT, BD957X_REG_INT_THERM_STAT),
51 	regmap_reg_range(BD957X_REG_INT_OVP_STAT, BD957X_REG_INT_SYS_STAT),
52 	regmap_reg_range(BD957X_REG_INT_MAIN_STAT, BD957X_REG_INT_MAIN_STAT),
53 };
54 
55 static const struct regmap_access_table volatile_regs = {
56 	.yes_ranges = &volatile_ranges[0],
57 	.n_yes_ranges = ARRAY_SIZE(volatile_ranges),
58 };
59 
60 static struct regmap_config bd957x_regmap = {
61 	.reg_bits = 8,
62 	.val_bits = 8,
63 	.volatile_table = &volatile_regs,
64 	.max_register = BD957X_MAX_REGISTER,
65 	.cache_type = REGCACHE_RBTREE,
66 };
67 
68 static struct regmap_irq bd9576_irqs[] = {
69 	REGMAP_IRQ_REG(BD9576_INT_THERM, 0, BD957X_MASK_INT_MAIN_THERM),
70 	REGMAP_IRQ_REG(BD9576_INT_OVP, 0, BD957X_MASK_INT_MAIN_OVP),
71 	REGMAP_IRQ_REG(BD9576_INT_SCP, 0, BD957X_MASK_INT_MAIN_SCP),
72 	REGMAP_IRQ_REG(BD9576_INT_OCP, 0, BD957X_MASK_INT_MAIN_OCP),
73 	REGMAP_IRQ_REG(BD9576_INT_OVD, 0, BD957X_MASK_INT_MAIN_OVD),
74 	REGMAP_IRQ_REG(BD9576_INT_UVD, 0, BD957X_MASK_INT_MAIN_UVD),
75 	REGMAP_IRQ_REG(BD9576_INT_UVP, 0, BD957X_MASK_INT_MAIN_UVP),
76 	REGMAP_IRQ_REG(BD9576_INT_SYS, 0, BD957X_MASK_INT_MAIN_SYS),
77 };
78 
79 static struct regmap_irq_chip bd9576_irq_chip = {
80 	.name = "bd9576_irq",
81 	.irqs = &bd9576_irqs[0],
82 	.num_irqs = ARRAY_SIZE(bd9576_irqs),
83 	.status_base = BD957X_REG_INT_MAIN_STAT,
84 	.mask_base = BD957X_REG_INT_MAIN_MASK,
85 	.ack_base = BD957X_REG_INT_MAIN_STAT,
86 	.init_ack_masked = true,
87 	.num_regs = 1,
88 	.irq_reg_stride = 1,
89 };
90 
91 static int bd957x_i2c_probe(struct i2c_client *i2c)
92 {
93 	int ret;
94 	struct regmap *regmap;
95 	struct mfd_cell *cells;
96 	int num_cells;
97 	unsigned long chip_type;
98 	struct irq_domain *domain;
99 	bool usable_irqs;
100 
101 	chip_type = (unsigned long)of_device_get_match_data(&i2c->dev);
102 
103 	switch (chip_type) {
104 	case ROHM_CHIP_TYPE_BD9576:
105 		cells = bd9576_mfd_cells;
106 		num_cells = ARRAY_SIZE(bd9576_mfd_cells);
107 		usable_irqs = !!i2c->irq;
108 		break;
109 	case ROHM_CHIP_TYPE_BD9573:
110 		cells = bd9573_mfd_cells;
111 		num_cells = ARRAY_SIZE(bd9573_mfd_cells);
112 		/*
113 		 * BD9573 only supports fatal IRQs which we can not handle
114 		 * because SoC is going to lose the power.
115 		 */
116 		usable_irqs = false;
117 		break;
118 	default:
119 		dev_err(&i2c->dev, "Unknown device type");
120 		return -EINVAL;
121 	}
122 
123 	regmap = devm_regmap_init_i2c(i2c, &bd957x_regmap);
124 	if (IS_ERR(regmap))
125 		return dev_err_probe(&i2c->dev, PTR_ERR(regmap),
126 				     "Failed to initialize Regmap\n");
127 
128 	/*
129 	 * BD9576 behaves badly. It kepts IRQ line asserted for the whole
130 	 * duration of detected HW condition (like over temperature). So we
131 	 * don't require IRQ to be populated.
132 	 * If IRQ information is not given, then we mask all IRQs and do not
133 	 * provide IRQ resources to regulator driver - which then just omits
134 	 * the notifiers.
135 	 */
136 	if (usable_irqs) {
137 		struct regmap_irq_chip_data *irq_data;
138 		struct mfd_cell *regulators;
139 
140 		regulators = &bd9576_mfd_cells[BD957X_REGULATOR_CELL];
141 		regulators->resources = bd9576_regulator_irqs;
142 		regulators->num_resources = ARRAY_SIZE(bd9576_regulator_irqs);
143 
144 		ret = devm_regmap_add_irq_chip(&i2c->dev, regmap, i2c->irq,
145 					       IRQF_ONESHOT, 0,
146 					       &bd9576_irq_chip, &irq_data);
147 		if (ret)
148 			return dev_err_probe(&i2c->dev, ret,
149 					     "Failed to add IRQ chip\n");
150 
151 		domain = regmap_irq_get_domain(irq_data);
152 	} else {
153 		ret = regmap_update_bits(regmap, BD957X_REG_INT_MAIN_MASK,
154 					 BD957X_MASK_INT_ALL,
155 					 BD957X_MASK_INT_ALL);
156 		if (ret)
157 			return ret;
158 		domain = NULL;
159 	}
160 
161 	ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO, cells,
162 				   num_cells, NULL, 0, domain);
163 	if (ret)
164 		dev_err_probe(&i2c->dev, ret, "Failed to create subdevices\n");
165 
166 	return ret;
167 }
168 
169 static const struct of_device_id bd957x_of_match[] = {
170 	{ .compatible = "rohm,bd9576", .data = (void *)ROHM_CHIP_TYPE_BD9576, },
171 	{ .compatible = "rohm,bd9573", .data = (void *)ROHM_CHIP_TYPE_BD9573, },
172 	{ },
173 };
174 MODULE_DEVICE_TABLE(of, bd957x_of_match);
175 
176 static struct i2c_driver bd957x_drv = {
177 	.driver = {
178 		.name = "rohm-bd957x",
179 		.of_match_table = bd957x_of_match,
180 	},
181 	.probe = bd957x_i2c_probe,
182 };
183 module_i2c_driver(bd957x_drv);
184 
185 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
186 MODULE_DESCRIPTION("ROHM BD9576MUF and BD9573MUF Power Management IC driver");
187 MODULE_LICENSE("GPL");
188