xref: /openbmc/linux/drivers/mfd/altera-a10sr.c (revision 3dc4b6fb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Altera Arria10 DevKit System Resource MFD Driver
4  *
5  * Author: Thor Thayer <tthayer@opensource.altera.com>
6  *
7  * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
8  *
9  * SPI access for Altera Arria10 MAX5 System Resource Chip
10  *
11  * Adapted from DA9052
12  */
13 
14 #include <linux/mfd/altera-a10sr.h>
15 #include <linux/mfd/core.h>
16 #include <linux/init.h>
17 #include <linux/of.h>
18 #include <linux/spi/spi.h>
19 
20 static const struct mfd_cell altr_a10sr_subdev_info[] = {
21 	{
22 		.name = "altr_a10sr_gpio",
23 		.of_compatible = "altr,a10sr-gpio",
24 	},
25 	{
26 		.name = "altr_a10sr_reset",
27 		.of_compatible = "altr,a10sr-reset",
28 	},
29 };
30 
31 static bool altr_a10sr_reg_readable(struct device *dev, unsigned int reg)
32 {
33 	switch (reg) {
34 	case ALTR_A10SR_VERSION_READ:
35 	case ALTR_A10SR_LED_REG:
36 	case ALTR_A10SR_PBDSW_REG:
37 	case ALTR_A10SR_PBDSW_IRQ_REG:
38 	case ALTR_A10SR_PWR_GOOD1_REG:
39 	case ALTR_A10SR_PWR_GOOD2_REG:
40 	case ALTR_A10SR_PWR_GOOD3_REG:
41 	case ALTR_A10SR_FMCAB_REG:
42 	case ALTR_A10SR_HPS_RST_REG:
43 	case ALTR_A10SR_USB_QSPI_REG:
44 	case ALTR_A10SR_SFPA_REG:
45 	case ALTR_A10SR_SFPB_REG:
46 	case ALTR_A10SR_I2C_M_REG:
47 	case ALTR_A10SR_WARM_RST_REG:
48 	case ALTR_A10SR_WR_KEY_REG:
49 	case ALTR_A10SR_PMBUS_REG:
50 		return true;
51 	default:
52 		return false;
53 	}
54 }
55 
56 static bool altr_a10sr_reg_writeable(struct device *dev, unsigned int reg)
57 {
58 	switch (reg) {
59 	case ALTR_A10SR_LED_REG:
60 	case ALTR_A10SR_PBDSW_IRQ_REG:
61 	case ALTR_A10SR_FMCAB_REG:
62 	case ALTR_A10SR_HPS_RST_REG:
63 	case ALTR_A10SR_USB_QSPI_REG:
64 	case ALTR_A10SR_SFPA_REG:
65 	case ALTR_A10SR_SFPB_REG:
66 	case ALTR_A10SR_WARM_RST_REG:
67 	case ALTR_A10SR_WR_KEY_REG:
68 	case ALTR_A10SR_PMBUS_REG:
69 		return true;
70 	default:
71 		return false;
72 	}
73 }
74 
75 static bool altr_a10sr_reg_volatile(struct device *dev, unsigned int reg)
76 {
77 	switch (reg) {
78 	case ALTR_A10SR_PBDSW_REG:
79 	case ALTR_A10SR_PBDSW_IRQ_REG:
80 	case ALTR_A10SR_PWR_GOOD1_REG:
81 	case ALTR_A10SR_PWR_GOOD2_REG:
82 	case ALTR_A10SR_PWR_GOOD3_REG:
83 	case ALTR_A10SR_HPS_RST_REG:
84 	case ALTR_A10SR_I2C_M_REG:
85 	case ALTR_A10SR_WARM_RST_REG:
86 	case ALTR_A10SR_WR_KEY_REG:
87 	case ALTR_A10SR_PMBUS_REG:
88 		return true;
89 	default:
90 		return false;
91 	}
92 }
93 
94 static const struct regmap_config altr_a10sr_regmap_config = {
95 	.reg_bits = 8,
96 	.val_bits = 8,
97 
98 	.cache_type = REGCACHE_NONE,
99 
100 	.use_single_read = true,
101 	.use_single_write = true,
102 	.read_flag_mask = 1,
103 	.write_flag_mask = 0,
104 
105 	.max_register = ALTR_A10SR_WR_KEY_REG,
106 	.readable_reg = altr_a10sr_reg_readable,
107 	.writeable_reg = altr_a10sr_reg_writeable,
108 	.volatile_reg = altr_a10sr_reg_volatile,
109 
110 };
111 
112 static int altr_a10sr_spi_probe(struct spi_device *spi)
113 {
114 	int ret;
115 	struct altr_a10sr *a10sr;
116 
117 	a10sr = devm_kzalloc(&spi->dev, sizeof(*a10sr),
118 			     GFP_KERNEL);
119 	if (!a10sr)
120 		return -ENOMEM;
121 
122 	spi->mode = SPI_MODE_3;
123 	spi->bits_per_word = 8;
124 	spi_setup(spi);
125 
126 	a10sr->dev = &spi->dev;
127 
128 	spi_set_drvdata(spi, a10sr);
129 
130 	a10sr->regmap = devm_regmap_init_spi(spi, &altr_a10sr_regmap_config);
131 	if (IS_ERR(a10sr->regmap)) {
132 		ret = PTR_ERR(a10sr->regmap);
133 		dev_err(&spi->dev, "Failed to allocate register map: %d\n",
134 			ret);
135 		return ret;
136 	}
137 
138 	ret = devm_mfd_add_devices(a10sr->dev, PLATFORM_DEVID_AUTO,
139 				   altr_a10sr_subdev_info,
140 				   ARRAY_SIZE(altr_a10sr_subdev_info),
141 				   NULL, 0, NULL);
142 	if (ret)
143 		dev_err(a10sr->dev, "Failed to register sub-devices: %d\n",
144 			ret);
145 
146 	return ret;
147 }
148 
149 static const struct of_device_id altr_a10sr_spi_of_match[] = {
150 	{ .compatible = "altr,a10sr" },
151 	{ },
152 };
153 
154 static struct spi_driver altr_a10sr_spi_driver = {
155 	.probe = altr_a10sr_spi_probe,
156 	.driver = {
157 		.name = "altr_a10sr",
158 		.of_match_table = of_match_ptr(altr_a10sr_spi_of_match),
159 	},
160 };
161 builtin_driver(altr_a10sr_spi_driver, spi_register_driver)
162