xref: /linux-6.15/include/linux/wwan.h (revision e5432cc7)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* Copyright (c) 2021, Linaro Ltd <[email protected]> */
3 
4 #ifndef __WWAN_H
5 #define __WWAN_H
6 
7 #include <linux/device.h>
8 #include <linux/kernel.h>
9 #include <linux/skbuff.h>
10 
11 /**
12  * enum wwan_port_type - WWAN port types
13  * @WWAN_PORT_AT: AT commands
14  * @WWAN_PORT_MBIM: Mobile Broadband Interface Model control
15  * @WWAN_PORT_QMI: Qcom modem/MSM interface for modem control
16  * @WWAN_PORT_QCDM: Qcom Modem diagnostic interface
17  * @WWAN_PORT_FIREHOSE: XML based command protocol
18  * @WWAN_PORT_UNKNOWN: Unknown port type
19  * @WWAN_PORT_MAX: Number of supported port types
20  */
21 enum wwan_port_type {
22 	WWAN_PORT_AT,
23 	WWAN_PORT_MBIM,
24 	WWAN_PORT_QMI,
25 	WWAN_PORT_QCDM,
26 	WWAN_PORT_FIREHOSE,
27 	WWAN_PORT_UNKNOWN,
28 	WWAN_PORT_MAX = WWAN_PORT_UNKNOWN,
29 };
30 
31 struct wwan_port;
32 
33 /** struct wwan_port_ops - The WWAN port operations
34  * @start: The routine for starting the WWAN port device.
35  * @stop: The routine for stopping the WWAN port device.
36  * @tx: The routine that sends WWAN port protocol data to the device.
37  *
38  * The wwan_port_ops structure contains a list of low-level operations
39  * that control a WWAN port device. All functions are mandatory.
40  */
41 struct wwan_port_ops {
42 	int (*start)(struct wwan_port *port);
43 	void (*stop)(struct wwan_port *port);
44 	int (*tx)(struct wwan_port *port, struct sk_buff *skb);
45 };
46 
47 /**
48  * wwan_create_port - Add a new WWAN port
49  * @parent: Device to use as parent and shared by all WWAN ports
50  * @type: WWAN port type
51  * @ops: WWAN port operations
52  * @drvdata: Pointer to caller driver data
53  *
54  * Allocate and register a new WWAN port. The port will be automatically exposed
55  * to user as a character device and attached to the right virtual WWAN device,
56  * based on the parent pointer. The parent pointer is the device shared by all
57  * components of a same WWAN modem (e.g. USB dev, PCI dev, MHI controller...).
58  *
59  * drvdata will be placed in the WWAN port device driver data and can be
60  * retrieved with wwan_port_get_drvdata().
61  *
62  * This function must be balanced with a call to wwan_remove_port().
63  *
64  * Returns a valid pointer to wwan_port on success or PTR_ERR on failure
65  */
66 struct wwan_port *wwan_create_port(struct device *parent,
67 				   enum wwan_port_type type,
68 				   const struct wwan_port_ops *ops,
69 				   void *drvdata);
70 
71 /**
72  * wwan_remove_port - Remove a WWAN port
73  * @port: WWAN port to remove
74  *
75  * Remove a previously created port.
76  */
77 void wwan_remove_port(struct wwan_port *port);
78 
79 /**
80  * wwan_port_rx - Receive data from the WWAN port
81  * @port: WWAN port for which data is received
82  * @skb: Pointer to the rx buffer
83  *
84  * A port driver calls this function upon data reception (MBIM, AT...).
85  */
86 void wwan_port_rx(struct wwan_port *port, struct sk_buff *skb);
87 
88 /**
89  * wwan_port_txoff - Stop TX on WWAN port
90  * @port: WWAN port for which TX must be stopped
91  *
92  * Used for TX flow control, a port driver calls this function to indicate TX
93  * is temporary unavailable (e.g. due to ring buffer fullness).
94  */
95 void wwan_port_txoff(struct wwan_port *port);
96 
97 
98 /**
99  * wwan_port_txon - Restart TX on WWAN port
100  * @port: WWAN port for which TX must be restarted
101  *
102  * Used for TX flow control, a port driver calls this function to indicate TX
103  * is available again.
104  */
105 void wwan_port_txon(struct wwan_port *port);
106 
107 /**
108  * wwan_port_get_drvdata - Retrieve driver data from a WWAN port
109  * @port: Related WWAN port
110  */
111 void *wwan_port_get_drvdata(struct wwan_port *port);
112 
113 #endif /* __WWAN_H */
114