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 * @WWAN_PORT_FASTBOOT: Fastboot protocol control
20 *
21 * @WWAN_PORT_MAX: Highest supported port types
22 * @WWAN_PORT_UNKNOWN: Special value to indicate an unknown port type
23 * @__WWAN_PORT_MAX: Internal use
24 */
25 enum wwan_port_type {
26 WWAN_PORT_AT,
27 WWAN_PORT_MBIM,
28 WWAN_PORT_QMI,
29 WWAN_PORT_QCDM,
30 WWAN_PORT_FIREHOSE,
31 WWAN_PORT_XMMRPC,
32 WWAN_PORT_FASTBOOT,
33
34 /* Add new port types above this line */
35
36 __WWAN_PORT_MAX,
37 WWAN_PORT_MAX = __WWAN_PORT_MAX - 1,
38 WWAN_PORT_UNKNOWN,
39 };
40
41 struct device;
42 struct file;
43 struct netlink_ext_ack;
44 struct sk_buff;
45 struct wwan_port;
46
47 /** struct wwan_port_ops - The WWAN port operations
48 * @start: The routine for starting the WWAN port device.
49 * @stop: The routine for stopping the WWAN port device.
50 * @tx: Non-blocking routine that sends WWAN port protocol data to the device.
51 * @tx_blocking: Optional blocking routine that sends WWAN port protocol data
52 * to the device.
53 * @tx_poll: Optional routine that sets additional TX poll flags.
54 *
55 * The wwan_port_ops structure contains a list of low-level operations
56 * that control a WWAN port device. All functions are mandatory unless specified.
57 */
58 struct wwan_port_ops {
59 int (*start)(struct wwan_port *port);
60 void (*stop)(struct wwan_port *port);
61 int (*tx)(struct wwan_port *port, struct sk_buff *skb);
62
63 /* Optional operations */
64 int (*tx_blocking)(struct wwan_port *port, struct sk_buff *skb);
65 __poll_t (*tx_poll)(struct wwan_port *port, struct file *filp,
66 poll_table *wait);
67 };
68
69 /** struct wwan_port_caps - The WWAN port capbilities
70 * @frag_len: WWAN port TX fragments length
71 * @headroom_len: WWAN port TX fragments reserved headroom length
72 */
73 struct wwan_port_caps {
74 size_t frag_len;
75 unsigned int headroom_len;
76 };
77
78 /**
79 * wwan_create_port - Add a new WWAN port
80 * @parent: Device to use as parent and shared by all WWAN ports
81 * @type: WWAN port type
82 * @ops: WWAN port operations
83 * @caps: WWAN port capabilities
84 * @drvdata: Pointer to caller driver data
85 *
86 * Allocate and register a new WWAN port. The port will be automatically exposed
87 * to user as a character device and attached to the right virtual WWAN device,
88 * based on the parent pointer. The parent pointer is the device shared by all
89 * components of a same WWAN modem (e.g. USB dev, PCI dev, MHI controller...).
90 *
91 * drvdata will be placed in the WWAN port device driver data and can be
92 * retrieved with wwan_port_get_drvdata().
93 *
94 * This function must be balanced with a call to wwan_remove_port().
95 *
96 * Returns a valid pointer to wwan_port on success or PTR_ERR on failure
97 */
98 struct wwan_port *wwan_create_port(struct device *parent,
99 enum wwan_port_type type,
100 const struct wwan_port_ops *ops,
101 struct wwan_port_caps *caps,
102 void *drvdata);
103
104 /**
105 * wwan_remove_port - Remove a WWAN port
106 * @port: WWAN port to remove
107 *
108 * Remove a previously created port.
109 */
110 void wwan_remove_port(struct wwan_port *port);
111
112 /**
113 * wwan_port_rx - Receive data from the WWAN port
114 * @port: WWAN port for which data is received
115 * @skb: Pointer to the rx buffer
116 *
117 * A port driver calls this function upon data reception (MBIM, AT...).
118 */
119 void wwan_port_rx(struct wwan_port *port, struct sk_buff *skb);
120
121 /**
122 * wwan_port_txoff - Stop TX on WWAN port
123 * @port: WWAN port for which TX must be stopped
124 *
125 * Used for TX flow control, a port driver calls this function to indicate TX
126 * is temporary unavailable (e.g. due to ring buffer fullness).
127 */
128 void wwan_port_txoff(struct wwan_port *port);
129
130
131 /**
132 * wwan_port_txon - Restart TX on WWAN port
133 * @port: WWAN port for which TX must be restarted
134 *
135 * Used for TX flow control, a port driver calls this function to indicate TX
136 * is available again.
137 */
138 void wwan_port_txon(struct wwan_port *port);
139
140 /**
141 * wwan_port_get_drvdata - Retrieve driver data from a WWAN port
142 * @port: Related WWAN port
143 */
144 void *wwan_port_get_drvdata(struct wwan_port *port);
145
146 /**
147 * struct wwan_netdev_priv - WWAN core network device private data
148 * @link_id: WWAN device data link id
149 * @drv_priv: driver private data area, size is determined in &wwan_ops
150 */
151 struct wwan_netdev_priv {
152 u32 link_id;
153
154 /* must be last */
155 u8 drv_priv[] __aligned(sizeof(void *));
156 };
157
wwan_netdev_drvpriv(struct net_device * dev)158 static inline void *wwan_netdev_drvpriv(struct net_device *dev)
159 {
160 return ((struct wwan_netdev_priv *)netdev_priv(dev))->drv_priv;
161 }
162
163 /*
164 * Used to indicate that the WWAN core should not create a default network
165 * link.
166 */
167 #define WWAN_NO_DEFAULT_LINK U32_MAX
168
169 /**
170 * struct wwan_ops - WWAN device ops
171 * @priv_size: size of private netdev data area
172 * @setup: set up a new netdev
173 * @newlink: register the new netdev
174 * @dellink: remove the given netdev
175 */
176 struct wwan_ops {
177 unsigned int priv_size;
178 void (*setup)(struct net_device *dev);
179 int (*newlink)(void *ctxt, struct net_device *dev,
180 u32 if_id, struct netlink_ext_ack *extack);
181 void (*dellink)(void *ctxt, struct net_device *dev,
182 struct list_head *head);
183 };
184
185 int wwan_register_ops(struct device *parent, const struct wwan_ops *ops,
186 void *ctxt, u32 def_link_id);
187
188 void wwan_unregister_ops(struct device *parent);
189
190 #ifdef CONFIG_WWAN_DEBUGFS
191 struct dentry *wwan_get_debugfs_dir(struct device *parent);
192 void wwan_put_debugfs_dir(struct dentry *dir);
193 #else
wwan_get_debugfs_dir(struct device * parent)194 static inline struct dentry *wwan_get_debugfs_dir(struct device *parent)
195 {
196 return ERR_PTR(-ENODEV);
197 }
wwan_put_debugfs_dir(struct dentry * dir)198 static inline void wwan_put_debugfs_dir(struct dentry *dir) {}
199 #endif
200
201 #endif /* __WWAN_H */
202