1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* Copyright (c) 2021, Linaro Ltd <loic.poulain@linaro.org> */
3
4 #ifndef __WWAN_H
5 #define __WWAN_H
6
7 #include <linux/device.h>
8 #include <linux/kernel.h>
9 #include <linux/poll.h>
10 #include <linux/skbuff.h>
11 #include <linux/netlink.h>
12 #include <linux/netdevice.h>
13
14 /**
15 * enum wwan_port_type - WWAN port types
16 * @WWAN_PORT_AT: AT commands
17 * @WWAN_PORT_MBIM: Mobile Broadband Interface Model control
18 * @WWAN_PORT_QMI: Qcom modem/MSM interface for modem control
19 * @WWAN_PORT_QCDM: Qcom Modem diagnostic interface
20 * @WWAN_PORT_FIREHOSE: XML based command protocol
21 *
22 * @WWAN_PORT_MAX: Highest supported port types
23 * @WWAN_PORT_UNKNOWN: Special value to indicate an unknown port type
24 * @__WWAN_PORT_MAX: Internal use
25 */
26 enum wwan_port_type {
27 WWAN_PORT_AT,
28 WWAN_PORT_MBIM,
29 WWAN_PORT_QMI,
30 WWAN_PORT_QCDM,
31 WWAN_PORT_FIREHOSE,
32
33 /* Add new port types above this line */
34
35 __WWAN_PORT_MAX,
36 WWAN_PORT_MAX = __WWAN_PORT_MAX - 1,
37 WWAN_PORT_UNKNOWN,
38 };
39
40 struct wwan_port;
41
42 /** struct wwan_port_ops - The WWAN port operations
43 * @start: The routine for starting the WWAN port device.
44 * @stop: The routine for stopping the WWAN port device.
45 * @tx: Non-blocking routine that sends WWAN port protocol data to the device.
46 * @tx_blocking: Optional blocking routine that sends WWAN port protocol data
47 * to the device.
48 * @tx_poll: Optional routine that sets additional TX poll flags.
49 *
50 * The wwan_port_ops structure contains a list of low-level operations
51 * that control a WWAN port device. All functions are mandatory unless specified.
52 */
53 struct wwan_port_ops {
54 int (*start)(struct wwan_port *port);
55 void (*stop)(struct wwan_port *port);
56 int (*tx)(struct wwan_port *port, struct sk_buff *skb);
57
58 /* Optional operations */
59 int (*tx_blocking)(struct wwan_port *port, struct sk_buff *skb);
60 __poll_t (*tx_poll)(struct wwan_port *port, struct file *filp,
61 poll_table *wait);
62 };
63
64 /**
65 * wwan_create_port - Add a new WWAN port
66 * @parent: Device to use as parent and shared by all WWAN ports
67 * @type: WWAN port type
68 * @ops: WWAN port operations
69 * @drvdata: Pointer to caller driver data
70 *
71 * Allocate and register a new WWAN port. The port will be automatically exposed
72 * to user as a character device and attached to the right virtual WWAN device,
73 * based on the parent pointer. The parent pointer is the device shared by all
74 * components of a same WWAN modem (e.g. USB dev, PCI dev, MHI controller...).
75 *
76 * drvdata will be placed in the WWAN port device driver data and can be
77 * retrieved with wwan_port_get_drvdata().
78 *
79 * This function must be balanced with a call to wwan_remove_port().
80 *
81 * Returns a valid pointer to wwan_port on success or PTR_ERR on failure
82 */
83 struct wwan_port *wwan_create_port(struct device *parent,
84 enum wwan_port_type type,
85 const struct wwan_port_ops *ops,
86 void *drvdata);
87
88 /**
89 * wwan_remove_port - Remove a WWAN port
90 * @port: WWAN port to remove
91 *
92 * Remove a previously created port.
93 */
94 void wwan_remove_port(struct wwan_port *port);
95
96 /**
97 * wwan_port_rx - Receive data from the WWAN port
98 * @port: WWAN port for which data is received
99 * @skb: Pointer to the rx buffer
100 *
101 * A port driver calls this function upon data reception (MBIM, AT...).
102 */
103 void wwan_port_rx(struct wwan_port *port, struct sk_buff *skb);
104
105 /**
106 * wwan_port_txoff - Stop TX on WWAN port
107 * @port: WWAN port for which TX must be stopped
108 *
109 * Used for TX flow control, a port driver calls this function to indicate TX
110 * is temporary unavailable (e.g. due to ring buffer fullness).
111 */
112 void wwan_port_txoff(struct wwan_port *port);
113
114
115 /**
116 * wwan_port_txon - Restart TX on WWAN port
117 * @port: WWAN port for which TX must be restarted
118 *
119 * Used for TX flow control, a port driver calls this function to indicate TX
120 * is available again.
121 */
122 void wwan_port_txon(struct wwan_port *port);
123
124 /**
125 * wwan_port_get_drvdata - Retrieve driver data from a WWAN port
126 * @port: Related WWAN port
127 */
128 void *wwan_port_get_drvdata(struct wwan_port *port);
129
130 /**
131 * struct wwan_netdev_priv - WWAN core network device private data
132 * @link_id: WWAN device data link id
133 * @drv_priv: driver private data area, size is determined in &wwan_ops
134 */
135 struct wwan_netdev_priv {
136 u32 link_id;
137
138 /* must be last */
139 u8 drv_priv[] __aligned(sizeof(void *));
140 };
141
wwan_netdev_drvpriv(struct net_device * dev)142 static inline void *wwan_netdev_drvpriv(struct net_device *dev)
143 {
144 return ((struct wwan_netdev_priv *)netdev_priv(dev))->drv_priv;
145 }
146
147 /*
148 * Used to indicate that the WWAN core should not create a default network
149 * link.
150 */
151 #define WWAN_NO_DEFAULT_LINK U32_MAX
152
153 /**
154 * struct wwan_ops - WWAN device ops
155 * @priv_size: size of private netdev data area
156 * @setup: set up a new netdev
157 * @newlink: register the new netdev
158 * @dellink: remove the given netdev
159 */
160 struct wwan_ops {
161 unsigned int priv_size;
162 void (*setup)(struct net_device *dev);
163 int (*newlink)(void *ctxt, struct net_device *dev,
164 u32 if_id, struct netlink_ext_ack *extack);
165 void (*dellink)(void *ctxt, struct net_device *dev,
166 struct list_head *head);
167 };
168
169 int wwan_register_ops(struct device *parent, const struct wwan_ops *ops,
170 void *ctxt, u32 def_link_id);
171
172 void wwan_unregister_ops(struct device *parent);
173
174 #endif /* __WWAN_H */
175