xref: /linux/drivers/mfd/motorola-cpcap.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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 
27 struct cpcap_ddata {
28 	struct spi_device *spi;
29 	struct regmap_irq *irqs;
30 	struct regmap_irq_chip_data *irqdata[CPCAP_NR_IRQ_CHIPS];
31 	const struct regmap_config *regmap_conf;
32 	struct regmap *regmap;
33 };
34 
35 static int cpcap_check_revision(struct cpcap_ddata *cpcap)
36 {
37 	u16 vendor, rev;
38 	int ret;
39 
40 	ret = cpcap_get_vendor(&cpcap->spi->dev, cpcap->regmap, &vendor);
41 	if (ret)
42 		return ret;
43 
44 	ret = cpcap_get_revision(&cpcap->spi->dev, cpcap->regmap, &rev);
45 	if (ret)
46 		return ret;
47 
48 	dev_info(&cpcap->spi->dev, "CPCAP vendor: %s rev: %i.%i (%x)\n",
49 		 vendor == CPCAP_VENDOR_ST ? "ST" : "TI",
50 		 CPCAP_REVISION_MAJOR(rev), CPCAP_REVISION_MINOR(rev),
51 		 rev);
52 
53 	if (rev < CPCAP_REVISION_2_1) {
54 		dev_info(&cpcap->spi->dev,
55 			 "Please add old CPCAP revision support as needed\n");
56 		return -ENODEV;
57 	}
58 
59 	return 0;
60 }
61 
62 /*
63  * First two irq chips are the two private macro interrupt chips, the third
64  * irq chip is for register banks 1 - 4 and is available for drivers to use.
65  */
66 static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
67 	{
68 		.name = "cpcap-m2",
69 		.num_regs = 1,
70 		.status_base = CPCAP_REG_MI1,
71 		.ack_base = CPCAP_REG_MI1,
72 		.mask_base = CPCAP_REG_MIM1,
73 		.use_ack = true,
74 	},
75 	{
76 		.name = "cpcap-m2",
77 		.num_regs = 1,
78 		.status_base = CPCAP_REG_MI2,
79 		.ack_base = CPCAP_REG_MI2,
80 		.mask_base = CPCAP_REG_MIM2,
81 		.use_ack = true,
82 	},
83 	{
84 		.name = "cpcap1-4",
85 		.num_regs = 4,
86 		.status_base = CPCAP_REG_INT1,
87 		.ack_base = CPCAP_REG_INT1,
88 		.mask_base = CPCAP_REG_INTM1,
89 		.type_base = CPCAP_REG_INTS1,
90 		.use_ack = true,
91 	},
92 };
93 
94 static void cpcap_init_one_regmap_irq(struct cpcap_ddata *cpcap,
95 				      struct regmap_irq *rirq,
96 				      int irq_base, int irq)
97 {
98 	unsigned int reg_offset;
99 	unsigned int bit, mask;
100 
101 	reg_offset = irq - irq_base;
102 	reg_offset /= cpcap->regmap_conf->val_bits;
103 	reg_offset *= cpcap->regmap_conf->reg_stride;
104 
105 	bit = irq % cpcap->regmap_conf->val_bits;
106 	mask = (1 << bit);
107 
108 	rirq->reg_offset = reg_offset;
109 	rirq->mask = mask;
110 }
111 
112 static int cpcap_init_irq_chip(struct cpcap_ddata *cpcap, int irq_chip,
113 			       int irq_start, int nr_irqs)
114 {
115 	struct regmap_irq_chip *chip = &cpcap_irq_chip[irq_chip];
116 	int i, ret;
117 
118 	for (i = irq_start; i < irq_start + nr_irqs; i++) {
119 		struct regmap_irq *rirq = &cpcap->irqs[i];
120 
121 		cpcap_init_one_regmap_irq(cpcap, rirq, irq_start, i);
122 	}
123 	chip->irqs = &cpcap->irqs[irq_start];
124 	chip->num_irqs = nr_irqs;
125 	chip->irq_drv_data = cpcap;
126 
127 	ret = devm_regmap_add_irq_chip(&cpcap->spi->dev, cpcap->regmap,
128 				       cpcap->spi->irq,
129 				       IRQF_TRIGGER_RISING |
130 				       IRQF_SHARED, -1,
131 				       chip, &cpcap->irqdata[irq_chip]);
132 	if (ret) {
133 		dev_err(&cpcap->spi->dev, "could not add irq chip %i: %i\n",
134 			irq_chip, ret);
135 		return ret;
136 	}
137 
138 	return 0;
139 }
140 
141 static int cpcap_init_irq(struct cpcap_ddata *cpcap)
142 {
143 	int ret;
144 
145 	cpcap->irqs = devm_kzalloc(&cpcap->spi->dev,
146 				   sizeof(*cpcap->irqs) *
147 				   CPCAP_NR_IRQ_REG_BANKS *
148 				   cpcap->regmap_conf->val_bits,
149 				   GFP_KERNEL);
150 	if (!cpcap->irqs)
151 		return -ENOMEM;
152 
153 	ret = cpcap_init_irq_chip(cpcap, 0, 0, 16);
154 	if (ret)
155 		return ret;
156 
157 	ret = cpcap_init_irq_chip(cpcap, 1, 16, 16);
158 	if (ret)
159 		return ret;
160 
161 	ret = cpcap_init_irq_chip(cpcap, 2, 32, 64);
162 	if (ret)
163 		return ret;
164 
165 	enable_irq_wake(cpcap->spi->irq);
166 
167 	return 0;
168 }
169 
170 static const struct of_device_id cpcap_of_match[] = {
171 	{ .compatible = "motorola,cpcap", },
172 	{ .compatible = "st,6556002", },
173 	{},
174 };
175 MODULE_DEVICE_TABLE(of, cpcap_of_match);
176 
177 static const struct regmap_config cpcap_regmap_config = {
178 	.reg_bits = 16,
179 	.reg_stride = 4,
180 	.pad_bits = 0,
181 	.val_bits = 16,
182 	.write_flag_mask = 0x8000,
183 	.max_register = CPCAP_REG_ST_TEST2,
184 	.cache_type = REGCACHE_NONE,
185 	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
186 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
187 };
188 
189 static int cpcap_probe(struct spi_device *spi)
190 {
191 	const struct of_device_id *match;
192 	struct cpcap_ddata *cpcap;
193 	int ret;
194 
195 	match = of_match_device(of_match_ptr(cpcap_of_match), &spi->dev);
196 	if (!match)
197 		return -ENODEV;
198 
199 	cpcap = devm_kzalloc(&spi->dev, sizeof(*cpcap), GFP_KERNEL);
200 	if (!cpcap)
201 		return -ENOMEM;
202 
203 	cpcap->spi = spi;
204 	spi_set_drvdata(spi, cpcap);
205 
206 	spi->bits_per_word = 16;
207 	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
208 
209 	ret = spi_setup(spi);
210 	if (ret)
211 		return ret;
212 
213 	cpcap->regmap_conf = &cpcap_regmap_config;
214 	cpcap->regmap = devm_regmap_init_spi(spi, &cpcap_regmap_config);
215 	if (IS_ERR(cpcap->regmap)) {
216 		ret = PTR_ERR(cpcap->regmap);
217 		dev_err(&cpcap->spi->dev, "Failed to initialize regmap: %d\n",
218 			ret);
219 
220 		return ret;
221 	}
222 
223 	ret = cpcap_check_revision(cpcap);
224 	if (ret) {
225 		dev_err(&cpcap->spi->dev, "Failed to detect CPCAP: %i\n", ret);
226 		return ret;
227 	}
228 
229 	ret = cpcap_init_irq(cpcap);
230 	if (ret)
231 		return ret;
232 
233 	return of_platform_populate(spi->dev.of_node, NULL, NULL,
234 				    &cpcap->spi->dev);
235 }
236 
237 static int cpcap_remove(struct spi_device *pdev)
238 {
239 	struct cpcap_ddata *cpcap = spi_get_drvdata(pdev);
240 
241 	of_platform_depopulate(&cpcap->spi->dev);
242 
243 	return 0;
244 }
245 
246 static struct spi_driver cpcap_driver = {
247 	.driver = {
248 		.name = "cpcap-core",
249 		.of_match_table = cpcap_of_match,
250 	},
251 	.probe = cpcap_probe,
252 	.remove = cpcap_remove,
253 };
254 module_spi_driver(cpcap_driver);
255 
256 MODULE_ALIAS("platform:cpcap");
257 MODULE_DESCRIPTION("CPCAP driver");
258 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
259 MODULE_LICENSE("GPL v2");
260