1
2
3
4#include <linux/device.h>
5#include <linux/errno.h>
6#include <linux/fsi-occ.h>
7#include <linux/i2c.h>
8#include <linux/jiffies.h>
9#include <linux/module.h>
10#include <linux/sched.h>
11#include <asm/unaligned.h>
12
13#include "common.h"
14
15#define OCC_TIMEOUT_MS 1000
16#define OCC_CMD_IN_PRG_WAIT_MS 50
17
18
19#define OCB_DATA1 0x6B035
20#define OCB_ADDR 0x6B070
21#define OCB_DATA3 0x6B075
22
23
24#define OCC_SRAM_ADDR_CMD 0xFFFF6000
25#define OCC_SRAM_ADDR_RESP 0xFFFF7000
26
27#define OCC_DATA_ATTN 0x20010000
28
29struct p8_i2c_occ {
30 struct occ occ;
31 struct i2c_client *client;
32};
33
34#define to_p8_i2c_occ(x) container_of((x), struct p8_i2c_occ, occ)
35
36static int p8_i2c_occ_getscom(struct i2c_client *client, u32 address, u8 *data)
37{
38 ssize_t rc;
39 __be64 buf;
40 struct i2c_msg msgs[2];
41
42
43 address <<= 1;
44
45 msgs[0].addr = client->addr;
46 msgs[0].flags = client->flags & I2C_M_TEN;
47 msgs[0].len = sizeof(u32);
48
49 msgs[0].buf = (char *)&address;
50
51
52 msgs[1].addr = client->addr;
53 msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
54 msgs[1].len = sizeof(u64);
55 msgs[1].buf = (char *)&buf;
56
57 rc = i2c_transfer(client->adapter, msgs, 2);
58 if (rc < 0)
59 return rc;
60
61 *(u64 *)data = be64_to_cpu(buf);
62
63 return 0;
64}
65
66static int p8_i2c_occ_putscom(struct i2c_client *client, u32 address, u8 *data)
67{
68 u32 buf[3];
69 ssize_t rc;
70
71
72 address <<= 1;
73
74
75 buf[0] = address;
76 memcpy(&buf[1], &data[4], sizeof(u32));
77 memcpy(&buf[2], data, sizeof(u32));
78
79 rc = i2c_master_send(client, (const char *)buf, sizeof(buf));
80 if (rc < 0)
81 return rc;
82 else if (rc != sizeof(buf))
83 return -EIO;
84
85 return 0;
86}
87
88static int p8_i2c_occ_putscom_u32(struct i2c_client *client, u32 address,
89 u32 data0, u32 data1)
90{
91 u8 buf[8];
92
93 memcpy(buf, &data0, 4);
94 memcpy(buf + 4, &data1, 4);
95
96 return p8_i2c_occ_putscom(client, address, buf);
97}
98
99static int p8_i2c_occ_putscom_be(struct i2c_client *client, u32 address,
100 u8 *data)
101{
102 __be32 data0, data1;
103
104 memcpy(&data0, data, 4);
105 memcpy(&data1, data + 4, 4);
106
107 return p8_i2c_occ_putscom_u32(client, address, be32_to_cpu(data0),
108 be32_to_cpu(data1));
109}
110
111static int p8_i2c_occ_send_cmd(struct occ *occ, u8 *cmd)
112{
113 int i, rc;
114 unsigned long start;
115 u16 data_length;
116 const unsigned long timeout = msecs_to_jiffies(OCC_TIMEOUT_MS);
117 const long wait_time = msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
118 struct p8_i2c_occ *ctx = to_p8_i2c_occ(occ);
119 struct i2c_client *client = ctx->client;
120 struct occ_response *resp = &occ->resp;
121
122 start = jiffies;
123
124
125 rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR, OCC_SRAM_ADDR_CMD, 0);
126 if (rc)
127 return rc;
128
129
130 rc = p8_i2c_occ_putscom_be(client, OCB_DATA3, cmd);
131 if (rc)
132 return rc;
133
134
135 rc = p8_i2c_occ_putscom_u32(client, OCB_DATA1, OCC_DATA_ATTN, 0);
136 if (rc)
137 return rc;
138
139 do {
140
141 rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR,
142 OCC_SRAM_ADDR_RESP, 0);
143 if (rc)
144 return rc;
145
146 rc = p8_i2c_occ_getscom(client, OCB_DATA3, (u8 *)resp);
147 if (rc)
148 return rc;
149
150
151 if (resp->return_status == OCC_RESP_CMD_IN_PRG) {
152 rc = -EALREADY;
153
154 if (time_after(jiffies, start + timeout))
155 break;
156
157 set_current_state(TASK_INTERRUPTIBLE);
158 schedule_timeout(wait_time);
159 }
160 } while (rc);
161
162
163 switch (resp->return_status) {
164 case OCC_RESP_CMD_IN_PRG:
165 rc = -ETIMEDOUT;
166 break;
167 case OCC_RESP_SUCCESS:
168 rc = 0;
169 break;
170 case OCC_RESP_CMD_INVAL:
171 case OCC_RESP_CMD_LEN_INVAL:
172 case OCC_RESP_DATA_INVAL:
173 case OCC_RESP_CHKSUM_ERR:
174 rc = -EINVAL;
175 break;
176 case OCC_RESP_INT_ERR:
177 case OCC_RESP_BAD_STATE:
178 case OCC_RESP_CRIT_EXCEPT:
179 case OCC_RESP_CRIT_INIT:
180 case OCC_RESP_CRIT_WATCHDOG:
181 case OCC_RESP_CRIT_OCB:
182 case OCC_RESP_CRIT_HW:
183 rc = -EREMOTEIO;
184 break;
185 default:
186 rc = -EPROTO;
187 }
188
189 if (rc < 0)
190 return rc;
191
192 data_length = get_unaligned_be16(&resp->data_length);
193 if (data_length > OCC_RESP_DATA_BYTES)
194 return -EMSGSIZE;
195
196
197 for (i = 8; i < data_length + 7; i += 8) {
198 rc = p8_i2c_occ_getscom(client, OCB_DATA3, ((u8 *)resp) + i);
199 if (rc)
200 return rc;
201 }
202
203 return 0;
204}
205
206static int p8_i2c_occ_probe(struct i2c_client *client,
207 const struct i2c_device_id *id)
208{
209 struct occ *occ;
210 struct p8_i2c_occ *ctx = devm_kzalloc(&client->dev, sizeof(*ctx),
211 GFP_KERNEL);
212 if (!ctx)
213 return -ENOMEM;
214
215 ctx->client = client;
216 occ = &ctx->occ;
217 occ->bus_dev = &client->dev;
218 dev_set_drvdata(&client->dev, occ);
219
220 occ->powr_sample_time_us = 250;
221 occ->poll_cmd_data = 0x10;
222 occ->send_cmd = p8_i2c_occ_send_cmd;
223
224 return occ_setup(occ, "p8_occ");
225}
226
227static int p8_i2c_occ_remove(struct i2c_client *client)
228{
229 struct occ *occ = dev_get_drvdata(&client->dev);
230
231 occ_shutdown(occ);
232
233 return 0;
234}
235
236static const struct of_device_id p8_i2c_occ_of_match[] = {
237 { .compatible = "ibm,p8-occ-hwmon" },
238 {}
239};
240MODULE_DEVICE_TABLE(of, p8_i2c_occ_of_match);
241
242static struct i2c_driver p8_i2c_occ_driver = {
243 .class = I2C_CLASS_HWMON,
244 .driver = {
245 .name = "occ-hwmon",
246 .of_match_table = p8_i2c_occ_of_match,
247 },
248 .probe = p8_i2c_occ_probe,
249 .remove = p8_i2c_occ_remove,
250};
251
252module_i2c_driver(p8_i2c_occ_driver);
253
254MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
255MODULE_DESCRIPTION("BMC P8 OCC hwmon driver");
256MODULE_LICENSE("GPL");
257
