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(&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_mark_last_busy(&mp2_dev->pci_dev->dev);
211	pm_runtime_put_autosuspend(&mp2_dev->pci_dev->dev);
212}
213
214#endif
215