xref: /openbmc/linux/drivers/mfd/motorola-cpcap.c (revision 2359ccdd)
1 /*
2  * Motorola CPCAP PMIC core driver
3  *
4  * Copyright (C) 2016 Tony Lindgren <tony@atomide.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/of_device.h>
18 #include <linux/regmap.h>
19 #include <linux/sysfs.h>
20 
21 #include <linux/mfd/motorola-cpcap.h>
22 #include <linux/spi/spi.h>
23 
24 #define CPCAP_NR_IRQ_REG_BANKS	6
25 #define CPCAP_NR_IRQ_CHIPS	3
26 #define CPCAP_REGISTER_SIZE	4
27 #define CPCAP_REGISTER_BITS	16
28 
29 struct cpcap_ddata {
30 	struct spi_device *spi;
31 	struct regmap_irq *irqs;
32 	struct regmap_irq_chip_data *irqdata[CPCAP_NR_IRQ_CHIPS];
33 	const struct regmap_config *regmap_conf;
34 	struct regmap *regmap;
35 };
36 
37 static int cpcap_sense_irq(struct regmap *regmap, int irq)
38 {
39 	int regnum = irq / CPCAP_REGISTER_BITS;
40 	int mask = BIT(irq % CPCAP_REGISTER_BITS);
41 	int reg = CPCAP_REG_INTS1 + (regnum * CPCAP_REGISTER_SIZE);
42 	int err, val;
43 
44 	if (reg < CPCAP_REG_INTS1 || reg > CPCAP_REG_INTS4)
45 		return -EINVAL;
46 
47 	err = regmap_read(regmap, reg, &val);
48 	if (err)
49 		return err;
50 
51 	return !!(val & mask);
52 }
53 
54 int cpcap_sense_virq(struct regmap *regmap, int virq)
55 {
56 	struct regmap_irq_chip_data *d = irq_get_chip_data(virq);
57 	int irq_base = regmap_irq_chip_get_base(d);
58 
59 	return cpcap_sense_irq(regmap, virq - irq_base);
60 }
61 EXPORT_SYMBOL_GPL(cpcap_sense_virq);
62 
63 static int cpcap_check_revision(struct cpcap_ddata *cpcap)
64 {
65 	u16 vendor, rev;
66 	int ret;
67 
68 	ret = cpcap_get_vendor(&cpcap->spi->dev, cpcap->regmap, &vendor);
69 	if (ret)
70 		return ret;
71 
72 	ret = cpcap_get_revision(&cpcap->spi->dev, cpcap->regmap, &rev);
73 	if (ret)
74 		return ret;
75 
76 	dev_info(&cpcap->spi->dev, "CPCAP vendor: %s rev: %i.%i (%x)\n",
77 		 vendor == CPCAP_VENDOR_ST ? "ST" : "TI",
78 		 CPCAP_REVISION_MAJOR(rev), CPCAP_REVISION_MINOR(rev),
79 		 rev);
80 
81 	if (rev < CPCAP_REVISION_2_1) {
82 		dev_info(&cpcap->spi->dev,
83 			 "Please add old CPCAP revision support as needed\n");
84 		return -ENODEV;
85 	}
86 
87 	return 0;
88 }
89 
90 /*
91  * First two irq chips are the two private macro interrupt chips, the third
92  * irq chip is for register banks 1 - 4 and is available for drivers to use.
93  */
94 static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
95 	{
96 		.name = "cpcap-m2",
97 		.num_regs = 1,
98 		.status_base = CPCAP_REG_MI1,
99 		.ack_base = CPCAP_REG_MI1,
100 		.mask_base = CPCAP_REG_MIM1,
101 		.use_ack = true,
102 		.ack_invert = true,
103 	},
104 	{
105 		.name = "cpcap-m2",
106 		.num_regs = 1,
107 		.status_base = CPCAP_REG_MI2,
108 		.ack_base = CPCAP_REG_MI2,
109 		.mask_base = CPCAP_REG_MIM2,
110 		.use_ack = true,
111 		.ack_invert = true,
112 	},
113 	{
114 		.name = "cpcap1-4",
115 		.num_regs = 4,
116 		.status_base = CPCAP_REG_INT1,
117 		.ack_base = CPCAP_REG_INT1,
118 		.mask_base = CPCAP_REG_INTM1,
119 		.use_ack = true,
120 		.ack_invert = true,
121 	},
122 };
123 
124 static void cpcap_init_one_regmap_irq(struct cpcap_ddata *cpcap,
125 				      struct regmap_irq *rirq,
126 				      int irq_base, int irq)
127 {
128 	unsigned int reg_offset;
129 	unsigned int bit, mask;
130 
131 	reg_offset = irq - irq_base;
132 	reg_offset /= cpcap->regmap_conf->val_bits;
133 	reg_offset *= cpcap->regmap_conf->reg_stride;
134 
135 	bit = irq % cpcap->regmap_conf->val_bits;
136 	mask = (1 << bit);
137 
138 	rirq->reg_offset = reg_offset;
139 	rirq->mask = mask;
140 }
141 
142 static int cpcap_init_irq_chip(struct cpcap_ddata *cpcap, int irq_chip,
143 			       int irq_start, int nr_irqs)
144 {
145 	struct regmap_irq_chip *chip = &cpcap_irq_chip[irq_chip];
146 	int i, ret;
147 
148 	for (i = irq_start; i < irq_start + nr_irqs; i++) {
149 		struct regmap_irq *rirq = &cpcap->irqs[i];
150 
151 		cpcap_init_one_regmap_irq(cpcap, rirq, irq_start, i);
152 	}
153 	chip->irqs = &cpcap->irqs[irq_start];
154 	chip->num_irqs = nr_irqs;
155 	chip->irq_drv_data = cpcap;
156 
157 	ret = devm_regmap_add_irq_chip(&cpcap->spi->dev, cpcap->regmap,
158 				       cpcap->spi->irq,
159 				       irq_get_trigger_type(cpcap->spi->irq) |
160 				       IRQF_SHARED, -1,
161 				       chip, &cpcap->irqdata[irq_chip]);
162 	if (ret) {
163 		dev_err(&cpcap->spi->dev, "could not add irq chip %i: %i\n",
164 			irq_chip, ret);
165 		return ret;
166 	}
167 
168 	return 0;
169 }
170 
171 static int cpcap_init_irq(struct cpcap_ddata *cpcap)
172 {
173 	int ret;
174 
175 	cpcap->irqs = devm_kzalloc(&cpcap->spi->dev,
176 				   sizeof(*cpcap->irqs) *
177 				   CPCAP_NR_IRQ_REG_BANKS *
178 				   cpcap->regmap_conf->val_bits,
179 				   GFP_KERNEL);
180 	if (!cpcap->irqs)
181 		return -ENOMEM;
182 
183 	ret = cpcap_init_irq_chip(cpcap, 0, 0, 16);
184 	if (ret)
185 		return ret;
186 
187 	ret = cpcap_init_irq_chip(cpcap, 1, 16, 16);
188 	if (ret)
189 		return ret;
190 
191 	ret = cpcap_init_irq_chip(cpcap, 2, 32, 64);
192 	if (ret)
193 		return ret;
194 
195 	enable_irq_wake(cpcap->spi->irq);
196 
197 	return 0;
198 }
199 
200 static const struct of_device_id cpcap_of_match[] = {
201 	{ .compatible = "motorola,cpcap", },
202 	{ .compatible = "st,6556002", },
203 	{},
204 };
205 MODULE_DEVICE_TABLE(of, cpcap_of_match);
206 
207 static const struct regmap_config cpcap_regmap_config = {
208 	.reg_bits = 16,
209 	.reg_stride = 4,
210 	.pad_bits = 0,
211 	.val_bits = 16,
212 	.write_flag_mask = 0x8000,
213 	.max_register = CPCAP_REG_ST_TEST2,
214 	.cache_type = REGCACHE_NONE,
215 	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
216 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
217 };
218 
219 static int cpcap_probe(struct spi_device *spi)
220 {
221 	const struct of_device_id *match;
222 	struct cpcap_ddata *cpcap;
223 	int ret;
224 
225 	match = of_match_device(of_match_ptr(cpcap_of_match), &spi->dev);
226 	if (!match)
227 		return -ENODEV;
228 
229 	cpcap = devm_kzalloc(&spi->dev, sizeof(*cpcap), GFP_KERNEL);
230 	if (!cpcap)
231 		return -ENOMEM;
232 
233 	cpcap->spi = spi;
234 	spi_set_drvdata(spi, cpcap);
235 
236 	spi->bits_per_word = 16;
237 	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
238 
239 	ret = spi_setup(spi);
240 	if (ret)
241 		return ret;
242 
243 	cpcap->regmap_conf = &cpcap_regmap_config;
244 	cpcap->regmap = devm_regmap_init_spi(spi, &cpcap_regmap_config);
245 	if (IS_ERR(cpcap->regmap)) {
246 		ret = PTR_ERR(cpcap->regmap);
247 		dev_err(&cpcap->spi->dev, "Failed to initialize regmap: %d\n",
248 			ret);
249 
250 		return ret;
251 	}
252 
253 	ret = cpcap_check_revision(cpcap);
254 	if (ret) {
255 		dev_err(&cpcap->spi->dev, "Failed to detect CPCAP: %i\n", ret);
256 		return ret;
257 	}
258 
259 	ret = cpcap_init_irq(cpcap);
260 	if (ret)
261 		return ret;
262 
263 	return devm_of_platform_populate(&cpcap->spi->dev);
264 }
265 
266 static struct spi_driver cpcap_driver = {
267 	.driver = {
268 		.name = "cpcap-core",
269 		.of_match_table = cpcap_of_match,
270 	},
271 	.probe = cpcap_probe,
272 };
273 module_spi_driver(cpcap_driver);
274 
275 MODULE_ALIAS("platform:cpcap");
276 MODULE_DESCRIPTION("CPCAP driver");
277 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
278 MODULE_LICENSE("GPL v2");
279