xref: /linux/drivers/mfd/smpro-core.c (revision cdd5b5a9761fd66d17586e4f4ba6588c70e640ea)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Ampere Altra Family SMPro core driver
4  * Copyright (c) 2022, Ampere Computing LLC
5  */
6 
7 #include <linux/i2c.h>
8 #include <linux/kernel.h>
9 #include <linux/mfd/core.h>
10 #include <linux/module.h>
11 #include <linux/of_platform.h>
12 #include <linux/regmap.h>
13 
14 /* Identification Registers */
15 #define MANUFACTURER_ID_REG     0x02
16 #define AMPERE_MANUFACTURER_ID  0xCD3A
17 
18 #define CORE_CE_ERR_DATA        0x82
19 #define CORE_UE_ERR_DATA        0x85
20 #define MEM_CE_ERR_DATA         0x92
21 #define MEM_UE_ERR_DATA         0x95
22 #define PCIE_CE_ERR_DATA        0xC2
23 #define PCIE_UE_ERR_DATA        0xC5
24 #define OTHER_CE_ERR_DATA       0xD2
25 #define OTHER_UE_ERR_DATA       0xDA
26 
smpro_core_write(void * context,const void * data,size_t count)27 static int smpro_core_write(void *context, const void *data, size_t count)
28 {
29 	struct device *dev = context;
30 	struct i2c_client *i2c = to_i2c_client(dev);
31 	int ret;
32 
33 	ret = i2c_master_send(i2c, data, count);
34 	if (unlikely(ret != count))
35 		return (ret < 0) ? ret : -EIO;
36 
37 	return 0;
38 }
39 
smpro_core_read(void * context,const void * reg,size_t reg_size,void * val,size_t val_size)40 static int smpro_core_read(void *context, const void *reg, size_t reg_size,
41 			   void *val, size_t val_size)
42 {
43 	struct device *dev = context;
44 	struct i2c_client *i2c = to_i2c_client(dev);
45 	struct i2c_msg xfer[2];
46 	unsigned char buf[2];
47 	int ret;
48 
49 	xfer[0].addr = i2c->addr;
50 	xfer[0].flags = 0;
51 
52 	buf[0] = *(u8 *)reg;
53 	buf[1] = val_size;
54 	xfer[0].len = 2;
55 	xfer[0].buf = buf;
56 
57 	xfer[1].addr = i2c->addr;
58 	xfer[1].flags = I2C_M_RD;
59 	xfer[1].len = val_size;
60 	xfer[1].buf = val;
61 
62 	ret = i2c_transfer(i2c->adapter, xfer, 2);
63 	if (unlikely(ret != 2))
64 		return (ret < 0) ? ret : -EIO;
65 
66 	return 0;
67 }
68 
69 static const struct regmap_bus smpro_regmap_bus = {
70 	.read = smpro_core_read,
71 	.write = smpro_core_write,
72 	.val_format_endian_default = REGMAP_ENDIAN_BIG,
73 };
74 
smpro_core_readable_noinc_reg(struct device * dev,unsigned int reg)75 static bool smpro_core_readable_noinc_reg(struct device *dev, unsigned int reg)
76 {
77 	return  (reg == CORE_CE_ERR_DATA || reg == CORE_UE_ERR_DATA ||
78 		 reg == MEM_CE_ERR_DATA || reg == MEM_UE_ERR_DATA ||
79 		 reg == PCIE_CE_ERR_DATA || reg == PCIE_UE_ERR_DATA ||
80 		 reg == OTHER_CE_ERR_DATA || reg == OTHER_UE_ERR_DATA);
81 }
82 
83 static const struct regmap_config smpro_regmap_config = {
84 	.reg_bits = 8,
85 	.val_bits = 16,
86 	.readable_noinc_reg = smpro_core_readable_noinc_reg,
87 };
88 
89 static const struct mfd_cell smpro_devs[] = {
90 	MFD_CELL_NAME("smpro-hwmon"),
91 	MFD_CELL_NAME("smpro-errmon"),
92 	MFD_CELL_NAME("smpro-misc"),
93 };
94 
smpro_core_probe(struct i2c_client * i2c)95 static int smpro_core_probe(struct i2c_client *i2c)
96 {
97 	const struct regmap_config *config;
98 	struct regmap *regmap;
99 	unsigned int val;
100 	int ret;
101 
102 	config = device_get_match_data(&i2c->dev);
103 	if (!config)
104 		return -EINVAL;
105 
106 	regmap = devm_regmap_init(&i2c->dev, &smpro_regmap_bus, &i2c->dev, config);
107 	if (IS_ERR(regmap))
108 		return PTR_ERR(regmap);
109 
110 	ret = regmap_read(regmap, MANUFACTURER_ID_REG, &val);
111 	if (ret)
112 		return ret;
113 
114 	if (val != AMPERE_MANUFACTURER_ID)
115 		return -ENODEV;
116 
117 	return devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO,
118 				    smpro_devs, ARRAY_SIZE(smpro_devs), NULL, 0, NULL);
119 }
120 
121 static const struct of_device_id smpro_core_of_match[] = {
122 	{ .compatible = "ampere,smpro", .data = &smpro_regmap_config },
123 	{}
124 };
125 MODULE_DEVICE_TABLE(of, smpro_core_of_match);
126 
127 static struct i2c_driver smpro_core_driver = {
128 	.probe = smpro_core_probe,
129 	.driver = {
130 		.name = "smpro-core",
131 		.of_match_table = smpro_core_of_match,
132 	},
133 };
134 module_i2c_driver(smpro_core_driver);
135 
136 MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
137 MODULE_DESCRIPTION("SMPRO CORE - I2C driver");
138 MODULE_LICENSE("GPL");
139