1/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
2/*
3 * AMD MP2 I2C adapter driver
4 *
5 * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
6 * Elie Morisse <syniurge@gmail.com>
7 */
8
9#ifndef I2C_AMD_PCI_MP2_H
10#define I2C_AMD_PCI_MP2_H
11
12#include <linux/i2c.h>
13#include <linux/pci.h>
14#include <linux/pm_runtime.h>
15
16#define PCI_DEVICE_ID_AMD_MP2 0x15E6
17
18struct amd_i2c_common;
19struct amd_mp2_dev;
20
21enum {
22 /* MP2 C2P Message Registers */
23 AMD_C2P_MSG0 = 0x10500, /* MP2 Message for I2C0 */
24 AMD_C2P_MSG1 = 0x10504, /* MP2 Message for I2C1 */
25 AMD_C2P_MSG2 = 0x10508, /* DRAM Address Lo / Data 0 */
26 AMD_C2P_MSG3 = 0x1050c, /* DRAM Address HI / Data 1 */
27 AMD_C2P_MSG4 = 0x10510, /* Data 2 */
28 AMD_C2P_MSG5 = 0x10514, /* Data 3 */
29 AMD_C2P_MSG6 = 0x10518, /* Data 4 */
30 AMD_C2P_MSG7 = 0x1051c, /* Data 5 */
31 AMD_C2P_MSG8 = 0x10520, /* Data 6 */
32 AMD_C2P_MSG9 = 0x10524, /* Data 7 */
33
34 /* MP2 P2C Message Registers */
35 AMD_P2C_MSG0 = 0x10680, /* Do not use */
36 AMD_P2C_MSG1 = 0x10684, /* I2C0 interrupt register */
37 AMD_P2C_MSG2 = 0x10688, /* I2C1 interrupt register */
38 AMD_P2C_MSG3 = 0x1068C, /* MP2 debug info */
39 AMD_P2C_MSG_INTEN = 0x10690, /* MP2 interrupt gen register */
40 AMD_P2C_MSG_INTSTS = 0x10694, /* Interrupt status */
41};
42
43/* Command register data structures */
44
45#define i2c_none (-1)
46enum i2c_cmd {
47 i2c_read = 0,
48 i2c_write,
49 i2c_enable,
50 i2c_disable,
51 number_of_sensor_discovered,
52 is_mp2_active,
53 invalid_cmd = 0xF,
54};
55
56enum speed_enum {
57 speed100k = 0,
58 speed400k = 1,
59 speed1000k = 2,
60 speed1400k = 3,
61 speed3400k = 4
62};
63
64enum mem_type {
65 use_dram = 0,
66 use_c2pmsg = 1,
67};
68
69/**
70 * union i2c_cmd_base : bit access of C2P commands
71 * @i2c_cmd: bit 0..3 i2c R/W command
72 * @bus_id: bit 4..7 i2c bus index
73 * @slave_addr: bit 8..15 slave address
74 * @length: bit 16..27 read/write length
75 * @i2c_speed: bit 28..30 bus speed
76 * @mem_type: bit 31 0-DRAM; 1-C2P msg o/p
77 */
78union i2c_cmd_base {
79 u32 ul;
80 struct {
81 enum i2c_cmd i2c_cmd : 4;
82 u8 bus_id : 4;
83 u32 slave_addr : 8;
84 u32 length : 12;
85 enum speed_enum i2c_speed : 3;
86 enum mem_type mem_type : 1;
87 } s;
88};
89
90enum response_type {
91 invalid_response = 0,
92 command_success = 1,
93 command_failed = 2,
94};
95
96enum status_type {
97 i2c_readcomplete_event = 0,
98 i2c_readfail_event = 1,
99 i2c_writecomplete_event = 2,
100 i2c_writefail_event = 3,
101 i2c_busenable_complete = 4,
102 i2c_busenable_failed = 5,
103 i2c_busdisable_complete = 6,
104 i2c_busdisable_failed = 7,
105 invalid_data_length = 8,
106 invalid_slave_address = 9,
107 invalid_i2cbus_id = 10,
108 invalid_dram_addr = 11,
109 invalid_command = 12,
110 mp2_active = 13,
111 numberof_sensors_discovered_resp = 14,
112 i2c_bus_notinitialized
113};
114
115/**
116 * union i2c_event : bit access of P2C events
117 * @response: bit 0..1 i2c response type
118 * @status: bit 2..6 status_type
119 * @mem_type: bit 7 0-DRAM; 1-C2P msg o/p
120 * @bus_id: bit 8..11 i2c bus id
121 * @length: bit 12..23 message length
122 * @slave_addr: bit 24-31 slave address
123 */
124union i2c_event {
125 u32 ul;
126 struct {
127 enum response_type response : 2;
128 enum status_type status : 5;
129 enum mem_type mem_type : 1;
130 u8 bus_id : 4;
131 u32 length : 12;
132 u32 slave_addr : 8;
133 } r;
134};
135
136/**
137 * struct amd_i2c_common - per bus/i2c adapter context, shared
138 * between the pci and the platform driver
139 * @eventval: MP2 event value set by the IRQ handler
140 * @mp2_dev: MP2 pci device this adapter is part of
141 * @msg: i2c message
142 * @cmd_completion: function called by the IRQ handler to signal
143 * the platform driver
144 * @reqcmd: requested i2c command type
145 * @cmd_success: set to true if the MP2 responded to a command with
146 * the expected status and response type
147 * @bus_id: bus index
148 * @i2c_speed: i2c bus speed determined by the slowest slave
149 * @dma_buf: if msg length > 32, holds the DMA buffer virtual address
150 * @dma_addr: if msg length > 32, holds the DMA buffer address
151 */
152struct amd_i2c_common {
153 union i2c_event eventval;
154 struct amd_mp2_dev *mp2_dev;
155 struct i2c_msg *msg;
156 void (*cmd_completion)(struct amd_i2c_common *i2c_common);
157 enum i2c_cmd reqcmd;
158 u8 cmd_success;
159 u8 bus_id;
160 enum speed_enum i2c_speed;
161 u8 *dma_buf;
162 dma_addr_t dma_addr;
163#ifdef CONFIG_PM
164 int (*suspend)(struct amd_i2c_common *i2c_common);
165 int (*resume)(struct amd_i2c_common *i2c_common);
166#endif /* CONFIG_PM */
167};
168
169/**
170 * struct amd_mp2_dev - per PCI device context
171 * @pci_dev: PCI driver node
172 * @busses: MP2 devices may have up to two busses,
173 * each bus corresponding to an i2c adapter
174 * @mmio: iommapped registers
175 * @c2p_lock: controls access to the C2P mailbox shared between
176 * the two adapters
177 * @c2p_lock_busid: id of the adapter which locked c2p_lock
178 */
179struct amd_mp2_dev {
180 struct pci_dev *pci_dev;
181 struct amd_i2c_common *busses[2];
182 void __iomem *mmio;
183 struct mutex c2p_lock;
184 u8 c2p_lock_busid;
185 unsigned int probed;
186 int dev_irq;
187};
188
189/* PCIe communication driver */
190
191int amd_mp2_rw(struct amd_i2c_common *i2c_common, enum i2c_cmd reqcmd);
192int amd_mp2_bus_enable_set(struct amd_i2c_common *i2c_common, bool enable);
193
194void amd_mp2_process_event(struct amd_i2c_common *i2c_common);
195
196void amd_mp2_rw_timeout(struct amd_i2c_common *i2c_common);
197
198int amd_mp2_register_cb(struct amd_i2c_common *i2c_common);
199int amd_mp2_unregister_cb(struct amd_i2c_common *i2c_common);
200
201struct amd_mp2_dev *amd_mp2_find_device(void);
202
203static inline void amd_mp2_pm_runtime_get(struct amd_mp2_dev *mp2_dev)
204{
205 pm_runtime_get_sync(dev: &mp2_dev->pci_dev->dev);
206}
207
208static inline void amd_mp2_pm_runtime_put(struct amd_mp2_dev *mp2_dev)
209{
210 pm_runtime_put_autosuspend(dev: &mp2_dev->pci_dev->dev);
211}
212
213#endif
214

source code of linux/drivers/i2c/busses/i2c-amd-mp2.h