xref: /openbmc/linux/drivers/mfd/altera-a10sr.c (revision 65417d9f)
1 /*
2  * Altera Arria10 DevKit System Resource MFD Driver
3  *
4  * Author: Thor Thayer <tthayer@opensource.altera.com>
5  *
6  * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2, as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program.  If not, see <http://www.gnu.org/licenses/>.
19  *
20  * SPI access for Altera Arria10 MAX5 System Resource Chip
21  *
22  * Adapted from DA9052
23  */
24 
25 #include <linux/mfd/altera-a10sr.h>
26 #include <linux/mfd/core.h>
27 #include <linux/init.h>
28 #include <linux/of.h>
29 #include <linux/spi/spi.h>
30 
31 static const struct mfd_cell altr_a10sr_subdev_info[] = {
32 	{
33 		.name = "altr_a10sr_gpio",
34 		.of_compatible = "altr,a10sr-gpio",
35 	},
36 	{
37 		.name = "altr_a10sr_reset",
38 		.of_compatible = "altr,a10sr-reset",
39 	},
40 };
41 
42 static bool altr_a10sr_reg_readable(struct device *dev, unsigned int reg)
43 {
44 	switch (reg) {
45 	case ALTR_A10SR_VERSION_READ:
46 	case ALTR_A10SR_LED_REG:
47 	case ALTR_A10SR_PBDSW_REG:
48 	case ALTR_A10SR_PBDSW_IRQ_REG:
49 	case ALTR_A10SR_PWR_GOOD1_REG:
50 	case ALTR_A10SR_PWR_GOOD2_REG:
51 	case ALTR_A10SR_PWR_GOOD3_REG:
52 	case ALTR_A10SR_FMCAB_REG:
53 	case ALTR_A10SR_HPS_RST_REG:
54 	case ALTR_A10SR_USB_QSPI_REG:
55 	case ALTR_A10SR_SFPA_REG:
56 	case ALTR_A10SR_SFPB_REG:
57 	case ALTR_A10SR_I2C_M_REG:
58 	case ALTR_A10SR_WARM_RST_REG:
59 	case ALTR_A10SR_WR_KEY_REG:
60 	case ALTR_A10SR_PMBUS_REG:
61 		return true;
62 	default:
63 		return false;
64 	}
65 }
66 
67 static bool altr_a10sr_reg_writeable(struct device *dev, unsigned int reg)
68 {
69 	switch (reg) {
70 	case ALTR_A10SR_LED_REG:
71 	case ALTR_A10SR_PBDSW_IRQ_REG:
72 	case ALTR_A10SR_FMCAB_REG:
73 	case ALTR_A10SR_HPS_RST_REG:
74 	case ALTR_A10SR_USB_QSPI_REG:
75 	case ALTR_A10SR_SFPA_REG:
76 	case ALTR_A10SR_SFPB_REG:
77 	case ALTR_A10SR_WARM_RST_REG:
78 	case ALTR_A10SR_WR_KEY_REG:
79 	case ALTR_A10SR_PMBUS_REG:
80 		return true;
81 	default:
82 		return false;
83 	}
84 }
85 
86 static bool altr_a10sr_reg_volatile(struct device *dev, unsigned int reg)
87 {
88 	switch (reg) {
89 	case ALTR_A10SR_PBDSW_REG:
90 	case ALTR_A10SR_PBDSW_IRQ_REG:
91 	case ALTR_A10SR_PWR_GOOD1_REG:
92 	case ALTR_A10SR_PWR_GOOD2_REG:
93 	case ALTR_A10SR_PWR_GOOD3_REG:
94 	case ALTR_A10SR_HPS_RST_REG:
95 	case ALTR_A10SR_I2C_M_REG:
96 	case ALTR_A10SR_WARM_RST_REG:
97 	case ALTR_A10SR_WR_KEY_REG:
98 	case ALTR_A10SR_PMBUS_REG:
99 		return true;
100 	default:
101 		return false;
102 	}
103 }
104 
105 static const struct regmap_config altr_a10sr_regmap_config = {
106 	.reg_bits = 8,
107 	.val_bits = 8,
108 
109 	.cache_type = REGCACHE_NONE,
110 
111 	.use_single_rw = true,
112 	.read_flag_mask = 1,
113 	.write_flag_mask = 0,
114 
115 	.max_register = ALTR_A10SR_WR_KEY_REG,
116 	.readable_reg = altr_a10sr_reg_readable,
117 	.writeable_reg = altr_a10sr_reg_writeable,
118 	.volatile_reg = altr_a10sr_reg_volatile,
119 
120 };
121 
122 static int altr_a10sr_spi_probe(struct spi_device *spi)
123 {
124 	int ret;
125 	struct altr_a10sr *a10sr;
126 
127 	a10sr = devm_kzalloc(&spi->dev, sizeof(*a10sr),
128 			     GFP_KERNEL);
129 	if (!a10sr)
130 		return -ENOMEM;
131 
132 	spi->mode = SPI_MODE_3;
133 	spi->bits_per_word = 8;
134 	spi_setup(spi);
135 
136 	a10sr->dev = &spi->dev;
137 
138 	spi_set_drvdata(spi, a10sr);
139 
140 	a10sr->regmap = devm_regmap_init_spi(spi, &altr_a10sr_regmap_config);
141 	if (IS_ERR(a10sr->regmap)) {
142 		ret = PTR_ERR(a10sr->regmap);
143 		dev_err(&spi->dev, "Failed to allocate register map: %d\n",
144 			ret);
145 		return ret;
146 	}
147 
148 	ret = devm_mfd_add_devices(a10sr->dev, PLATFORM_DEVID_AUTO,
149 				   altr_a10sr_subdev_info,
150 				   ARRAY_SIZE(altr_a10sr_subdev_info),
151 				   NULL, 0, NULL);
152 	if (ret)
153 		dev_err(a10sr->dev, "Failed to register sub-devices: %d\n",
154 			ret);
155 
156 	return ret;
157 }
158 
159 static const struct of_device_id altr_a10sr_spi_of_match[] = {
160 	{ .compatible = "altr,a10sr" },
161 	{ },
162 };
163 
164 static struct spi_driver altr_a10sr_spi_driver = {
165 	.probe = altr_a10sr_spi_probe,
166 	.driver = {
167 		.name = "altr_a10sr",
168 		.of_match_table = of_match_ptr(altr_a10sr_spi_of_match),
169 	},
170 };
171 builtin_driver(altr_a10sr_spi_driver, spi_register_driver)
172