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/poll.h>
8 #include <linux/netdevice.h>
9 #include <linux/types.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_XMMRPC: Control protocol for Intel XMM modems
19 *
20 * @WWAN_PORT_MAX: Highest supported port types
21 * @WWAN_PORT_UNKNOWN: Special value to indicate an unknown port type
22 * @__WWAN_PORT_MAX: Internal use
23 */
24 enum wwan_port_type {
25 WWAN_PORT_AT,
26 WWAN_PORT_MBIM,
27 WWAN_PORT_QMI,
28 WWAN_PORT_QCDM,
29 WWAN_PORT_FIREHOSE,
30 WWAN_PORT_XMMRPC,
31
32 /* Add new port types above this line */
33
34 __WWAN_PORT_MAX,
35 WWAN_PORT_MAX = __WWAN_PORT_MAX - 1,
36 WWAN_PORT_UNKNOWN,
37 };
38
39 struct device;
40 struct file;
41 struct netlink_ext_ack;
42 struct sk_buff;
43 struct wwan_port;
44
45 /** struct wwan_port_ops - The WWAN port operations
46 * @start: The routine for starting the WWAN port device.
47 * @stop: The routine for stopping the WWAN port device.
48 * @tx: Non-blocking routine that sends WWAN port protocol data to the device.
49 * @tx_blocking: Optional blocking routine that sends WWAN port protocol data
50 * to the device.
51 * @tx_poll: Optional routine that sets additional TX poll flags.
52 *
53 * The wwan_port_ops structure contains a list of low-level operations
54 * that control a WWAN port device. All functions are mandatory unless specified.
55 */
56 struct wwan_port_ops {
57 int (*start)(struct wwan_port *port);
58 void (*stop)(struct wwan_port *port);
59 int (*tx)(struct wwan_port *port, struct sk_buff *skb);
60
61 /* Optional operations */
62 int (*tx_blocking)(struct wwan_port *port, struct sk_buff *skb);
63 __poll_t (*tx_poll)(struct wwan_port *port, struct file *filp,
64 poll_table *wait);
65 };
66
67 /** struct wwan_port_caps - The WWAN port capbilities
68 * @frag_len: WWAN port TX fragments length
69 * @headroom_len: WWAN port TX fragments reserved headroom length
70 */
71 struct wwan_port_caps {
72 size_t frag_len;
73 unsigned int headroom_len;
74 };
75
76 /**
77 * wwan_create_port - Add a new WWAN port
78 * @parent: Device to use as parent and shared by all WWAN ports
79 * @type: WWAN port type
80 * @ops: WWAN port operations
81 * @caps: WWAN port capabilities
82 * @drvdata: Pointer to caller driver data
83 *
84 * Allocate and register a new WWAN port. The port will be automatically exposed
85 * to user as a character device and attached to the right virtual WWAN device,
86 * based on the parent pointer. The parent pointer is the device shared by all
87 * components of a same WWAN modem (e.g. USB dev, PCI dev, MHI controller...).
88 *
89 * drvdata will be placed in the WWAN port device driver data and can be
90 * retrieved with wwan_port_get_drvdata().
91 *
92 * This function must be balanced with a call to wwan_remove_port().
93 *
94 * Returns a valid pointer to wwan_port on success or PTR_ERR on failure
95 */
96 struct wwan_port *wwan_create_port(struct device *parent,
97 enum wwan_port_type type,
98 const struct wwan_port_ops *ops,
99 struct wwan_port_caps *caps,
100 void *drvdata);
101
102 /**
103 * wwan_remove_port - Remove a WWAN port
104 * @port: WWAN port to remove
105 *
106 * Remove a previously created port.
107 */
108 void wwan_remove_port(struct wwan_port *port);
109
110 /**
111 * wwan_port_rx - Receive data from the WWAN port
112 * @port: WWAN port for which data is received
113 * @skb: Pointer to the rx buffer
114 *
115 * A port driver calls this function upon data reception (MBIM, AT...).
116 */
117 void wwan_port_rx(struct wwan_port *port, struct sk_buff *skb);
118
119 /**
120 * wwan_port_txoff - Stop TX on WWAN port
121 * @port: WWAN port for which TX must be stopped
122 *
123 * Used for TX flow control, a port driver calls this function to indicate TX
124 * is temporary unavailable (e.g. due to ring buffer fullness).
125 */
126 void wwan_port_txoff(struct wwan_port *port);
127
128
129 /**
130 * wwan_port_txon - Restart TX on WWAN port
131 * @port: WWAN port for which TX must be restarted
132 *
133 * Used for TX flow control, a port driver calls this function to indicate TX
134 * is available again.
135 */
136 void wwan_port_txon(struct wwan_port *port);
137
138 /**
139 * wwan_port_get_drvdata - Retrieve driver data from a WWAN port
140 * @port: Related WWAN port
141 */
142 void *wwan_port_get_drvdata(struct wwan_port *port);
143
144 /**
145 * struct wwan_netdev_priv - WWAN core network device private data
146 * @link_id: WWAN device data link id
147 * @drv_priv: driver private data area, size is determined in &wwan_ops
148 */
149 struct wwan_netdev_priv {
150 u32 link_id;
151
152 /* must be last */
153 u8 drv_priv[] __aligned(sizeof(void *));
154 };
155
wwan_netdev_drvpriv(struct net_device * dev)156 static inline void *wwan_netdev_drvpriv(struct net_device *dev)
157 {
158 return ((struct wwan_netdev_priv *)netdev_priv(dev))->drv_priv;
159 }
160
161 /*
162 * Used to indicate that the WWAN core should not create a default network
163 * link.
164 */
165 #define WWAN_NO_DEFAULT_LINK U32_MAX
166
167 /**
168 * struct wwan_ops - WWAN device ops
169 * @priv_size: size of private netdev data area
170 * @setup: set up a new netdev
171 * @newlink: register the new netdev
172 * @dellink: remove the given netdev
173 */
174 struct wwan_ops {
175 unsigned int priv_size;
176 void (*setup)(struct net_device *dev);
177 int (*newlink)(void *ctxt, struct net_device *dev,
178 u32 if_id, struct netlink_ext_ack *extack);
179 void (*dellink)(void *ctxt, struct net_device *dev,
180 struct list_head *head);
181 };
182
183 int wwan_register_ops(struct device *parent, const struct wwan_ops *ops,
184 void *ctxt, u32 def_link_id);
185
186 void wwan_unregister_ops(struct device *parent);
187
188 #ifdef CONFIG_WWAN_DEBUGFS
189 struct dentry *wwan_get_debugfs_dir(struct device *parent);
190 void wwan_put_debugfs_dir(struct dentry *dir);
191 #else
wwan_get_debugfs_dir(struct device * parent)192 static inline struct dentry *wwan_get_debugfs_dir(struct device *parent)
193 {
194 return ERR_PTR(-ENODEV);
195 }
wwan_put_debugfs_dir(struct dentry * dir)196 static inline void wwan_put_debugfs_dir(struct dentry *dir) {}
197 #endif
198
199 #endif /* __WWAN_H */
200