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