1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   * Copyright (c) 2023, Intel Corporation. All rights reserved.
4   */
5  #ifndef _LINUX_USB_LJCA_H_
6  #define _LINUX_USB_LJCA_H_
7  
8  #include <linux/auxiliary_bus.h>
9  #include <linux/list.h>
10  #include <linux/spinlock.h>
11  #include <linux/types.h>
12  
13  #define LJCA_MAX_GPIO_NUM 64
14  
15  #define auxiliary_dev_to_ljca_client(auxiliary_dev)			\
16  		container_of(auxiliary_dev, struct ljca_client, auxdev)
17  
18  struct ljca_adapter;
19  
20  /**
21   * typedef ljca_event_cb_t - event callback function signature
22   *
23   * @context: the execution context of who registered this callback
24   * @cmd: the command from device for this event
25   * @evt_data: the event data payload
26   * @len: the event data payload length
27   *
28   * The callback function is called in interrupt context and the data payload is
29   * only valid during the call. If the user needs later access of the data, it
30   * must copy it.
31   */
32  typedef void (*ljca_event_cb_t)(void *context, u8 cmd, const void *evt_data, int len);
33  
34  /**
35   * struct ljca_client - represent a ljca client device
36   *
37   * @type: ljca client type
38   * @id: ljca client id within same client type
39   * @link: ljca client on the same ljca adapter
40   * @auxdev: auxiliary device object
41   * @adapter: ljca adapter the ljca client sit on
42   * @context: the execution context of the event callback
43   * @event_cb: ljca client driver register this callback to get
44   *	firmware asynchronous rx buffer pending notifications
45   * @event_cb_lock: spinlock to protect event callback
46   */
47  struct ljca_client {
48  	u8 type;
49  	u8 id;
50  	struct list_head link;
51  	struct auxiliary_device auxdev;
52  	struct ljca_adapter *adapter;
53  
54  	void *context;
55  	ljca_event_cb_t event_cb;
56  	/* lock to protect event_cb */
57  	spinlock_t event_cb_lock;
58  };
59  
60  /**
61   * struct ljca_gpio_info - ljca gpio client device info
62   *
63   * @num: ljca gpio client device pin number
64   * @valid_pin_map: ljca gpio client device valid pin mapping
65   */
66  struct ljca_gpio_info {
67  	unsigned int num;
68  	DECLARE_BITMAP(valid_pin_map, LJCA_MAX_GPIO_NUM);
69  };
70  
71  /**
72   * struct ljca_i2c_info - ljca i2c client device info
73   *
74   * @id: ljca i2c client device identification number
75   * @capacity: ljca i2c client device capacity
76   * @intr_pin: ljca i2c client device interrupt pin number if exists
77   */
78  struct ljca_i2c_info {
79  	u8 id;
80  	u8 capacity;
81  	u8 intr_pin;
82  };
83  
84  /**
85   * struct ljca_spi_info - ljca spi client device info
86   *
87   * @id: ljca spi client device identification number
88   * @capacity: ljca spi client device capacity
89   */
90  struct ljca_spi_info {
91  	u8 id;
92  	u8 capacity;
93  };
94  
95  /**
96   * ljca_register_event_cb - register a callback function to receive events
97   *
98   * @client: ljca client device
99   * @event_cb: callback function
100   * @context: execution context of event callback
101   *
102   * Return: 0 in case of success, negative value in case of error
103   */
104  int ljca_register_event_cb(struct ljca_client *client, ljca_event_cb_t event_cb, void *context);
105  
106  /**
107   * ljca_unregister_event_cb - unregister the callback function for an event
108   *
109   * @client: ljca client device
110   */
111  void ljca_unregister_event_cb(struct ljca_client *client);
112  
113  /**
114   * ljca_transfer - issue a LJCA command and wait for a response
115   *
116   * @client: ljca client device
117   * @cmd: the command to be sent to the device
118   * @obuf: the buffer to be sent to the device; it can be NULL if the user
119   *	doesn't need to transmit data with this command
120   * @obuf_len: the size of the buffer to be sent to the device; it should
121   *	be 0 when obuf is NULL
122   * @ibuf: any data associated with the response will be copied here; it can be
123   *	NULL if the user doesn't need the response data
124   * @ibuf_len: must be initialized to the input buffer size
125   *
126   * Return: the actual length of response data for success, negative value for errors
127   */
128  int ljca_transfer(struct ljca_client *client, u8 cmd, const u8 *obuf,
129  		  u8 obuf_len, u8 *ibuf, u8 ibuf_len);
130  
131  /**
132   * ljca_transfer_noack - issue a LJCA command without a response
133   *
134   * @client: ljca client device
135   * @cmd: the command to be sent to the device
136   * @obuf: the buffer to be sent to the device; it can be NULL if the user
137   *	doesn't need to transmit data with this command
138   * @obuf_len: the size of the buffer to be sent to the device
139   *
140   * Return: 0 for success, negative value for errors
141   */
142  int ljca_transfer_noack(struct ljca_client *client, u8 cmd, const u8 *obuf,
143  			u8 obuf_len);
144  
145  #endif
146