xref: /openbmc/linux/drivers/soundwire/bus.h (revision e3b9f1e8)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-17 Intel Corporation.
3 
4 #ifndef __SDW_BUS_H
5 #define __SDW_BUS_H
6 
7 #if IS_ENABLED(CONFIG_ACPI)
8 int sdw_acpi_find_slaves(struct sdw_bus *bus);
9 #else
10 static inline int sdw_acpi_find_slaves(struct sdw_bus *bus)
11 {
12 	return -ENOTSUPP;
13 }
14 #endif
15 
16 void sdw_extract_slave_id(struct sdw_bus *bus,
17 			u64 addr, struct sdw_slave_id *id);
18 
19 enum {
20 	SDW_MSG_FLAG_READ = 0,
21 	SDW_MSG_FLAG_WRITE,
22 };
23 
24 /**
25  * struct sdw_msg - Message structure
26  * @addr: Register address accessed in the Slave
27  * @len: number of messages
28  * @dev_num: Slave device number
29  * @addr_page1: SCP address page 1 Slave register
30  * @addr_page2: SCP address page 2 Slave register
31  * @flags: transfer flags, indicate if xfer is read or write
32  * @buf: message data buffer
33  * @ssp_sync: Send message at SSP (Stream Synchronization Point)
34  * @page: address requires paging
35  */
36 struct sdw_msg {
37 	u16 addr;
38 	u16 len;
39 	u8 dev_num;
40 	u8 addr_page1;
41 	u8 addr_page2;
42 	u8 flags;
43 	u8 *buf;
44 	bool ssp_sync;
45 	bool page;
46 };
47 
48 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg);
49 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
50 				struct sdw_defer *defer);
51 
52 #define SDW_READ_INTR_CLEAR_RETRY	10
53 
54 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
55 		u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf);
56 
57 /* Read-Modify-Write Slave register */
58 static inline int
59 sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
60 {
61 	int tmp;
62 
63 	tmp = sdw_read(slave, addr);
64 	if (tmp < 0)
65 		return tmp;
66 
67 	tmp = (tmp & ~mask) | val;
68 	return sdw_write(slave, addr, tmp);
69 }
70 
71 #endif /* __SDW_BUS_H */
72