xref: /linux/include/linux/usb/typec_altmode.h (revision c17ee635fd3a482b2ad2bf5e269755c2eae5f25e)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef __USB_TYPEC_ALTMODE_H
4 #define __USB_TYPEC_ALTMODE_H
5 
6 #include <linux/mod_devicetable.h>
7 #include <linux/usb/typec.h>
8 #include <linux/device.h>
9 
10 #define MODE_DISCOVERY_MAX	6
11 
12 extern const struct device_type typec_port_altmode_dev_type;
13 extern const struct device_type typec_plug_altmode_dev_type;
14 extern const struct device_type typec_partner_altmode_dev_type;
15 
16 #define is_typec_port_altmode(dev) ((dev)->type == &typec_port_altmode_dev_type)
17 #define is_typec_plug_altmode(dev) ((dev)->type == &typec_plug_altmode_dev_type)
18 #define is_typec_partner_altmode(dev) ((dev)->type == &typec_partner_altmode_dev_type)
19 
20 struct typec_altmode_ops;
21 
22 /**
23  * struct typec_altmode - USB Type-C alternate mode device
24  * @dev: Driver model's view of this device
25  * @svid: Standard or Vendor ID (SVID) of the alternate mode
26  * @mode: Index of the Mode
27  * @vdo: VDO returned by Discover Modes USB PD command
28  * @active: Tells has the mode been entered or not
29  * @desc: Optional human readable description of the mode
30  * @ops: Operations vector from the driver
31  * @cable_ops: Cable operations vector from the driver.
32  */
33 struct typec_altmode {
34 	struct device			dev;
35 	u16				svid;
36 	int				mode;
37 	u32				vdo;
38 	unsigned int			active:1;
39 	u8				priority;
40 	bool			mode_selection;
41 
42 	char				*desc;
43 	const struct typec_altmode_ops	*ops;
44 	const struct typec_cable_ops	*cable_ops;
45 };
46 
47 #define to_typec_altmode(d) container_of(d, struct typec_altmode, dev)
48 
49 static inline void typec_altmode_set_drvdata(struct typec_altmode *altmode,
50 					     void *data)
51 {
52 	dev_set_drvdata(&altmode->dev, data);
53 }
54 
55 static inline void *typec_altmode_get_drvdata(struct typec_altmode *altmode)
56 {
57 	return dev_get_drvdata(&altmode->dev);
58 }
59 
60 /**
61  * struct typec_altmode_ops - Alternate mode specific operations vector
62  * @enter: Operations to be executed with Enter Mode Command
63  * @exit: Operations to be executed with Exit Mode Command
64  * @attention: Callback for Attention Command
65  * @vdm: Callback for SVID specific commands
66  * @notify: Communication channel for platform and the alternate mode
67  * @activate: User callback for Enter/Exit Mode
68  */
69 struct typec_altmode_ops {
70 	int (*enter)(struct typec_altmode *altmode, u32 *vdo);
71 	int (*exit)(struct typec_altmode *altmode);
72 	void (*attention)(struct typec_altmode *altmode, u32 vdo);
73 	int (*vdm)(struct typec_altmode *altmode, const u32 hdr,
74 		   const u32 *vdo, int cnt);
75 	int (*notify)(struct typec_altmode *altmode, unsigned long conf,
76 		      void *data);
77 	int (*activate)(struct typec_altmode *altmode, int activate);
78 };
79 
80 int typec_altmode_enter(struct typec_altmode *altmode, u32 *vdo);
81 int typec_altmode_exit(struct typec_altmode *altmode);
82 int typec_altmode_attention(struct typec_altmode *altmode, u32 vdo);
83 int typec_altmode_vdm(struct typec_altmode *altmode,
84 		      const u32 header, const u32 *vdo, int count);
85 int typec_altmode_notify(struct typec_altmode *altmode, unsigned long conf,
86 			 void *data);
87 const struct typec_altmode *
88 typec_altmode_get_partner(struct typec_altmode *altmode);
89 
90 /**
91  * struct typec_cable_ops - Cable alternate mode operations vector
92  * @enter: Operations to be executed with Enter Mode Command
93  * @exit: Operations to be executed with Exit Mode Command
94  * @vdm: Callback for SVID specific commands
95  */
96 struct typec_cable_ops {
97 	int (*enter)(struct typec_altmode *altmode, enum typec_plug_index sop, u32 *vdo);
98 	int (*exit)(struct typec_altmode *altmode, enum typec_plug_index sop);
99 	int (*vdm)(struct typec_altmode *altmode, enum typec_plug_index sop,
100 		   const u32 hdr, const u32 *vdo, int cnt);
101 };
102 
103 int typec_cable_altmode_enter(struct typec_altmode *altmode, enum typec_plug_index sop, u32 *vdo);
104 int typec_cable_altmode_exit(struct typec_altmode *altmode, enum typec_plug_index sop);
105 int typec_cable_altmode_vdm(struct typec_altmode *altmode, enum typec_plug_index sop,
106 			    const u32 header, const u32 *vdo, int count);
107 
108 /**
109  * typec_altmode_get_cable_svdm_version - Get negotiated SVDM version for cable plug
110  * @altmode: Handle to the alternate mode
111  */
112 static inline int
113 typec_altmode_get_cable_svdm_version(struct typec_altmode *altmode)
114 {
115 	return typec_get_cable_svdm_version(typec_altmode2port(altmode));
116 }
117 
118 /*
119  * These are the connector states (USB, Safe and Alt Mode) defined in USB Type-C
120  * Specification. SVID specific connector states are expected to follow and
121  * start from the value TYPEC_STATE_MODAL.
122  */
123 enum {
124 	TYPEC_STATE_SAFE,	/* USB Safe State */
125 	TYPEC_STATE_USB,	/* USB Operation */
126 	TYPEC_STATE_MODAL,	/* Alternate Modes */
127 };
128 
129 /*
130  * For the muxes there is no difference between Accessory Modes and Alternate
131  * Modes, so the Accessory Modes are supplied with specific modal state values
132  * here. Unlike with Alternate Modes, where the mux will be linked with the
133  * alternate mode device, the mux for Accessory Modes will be linked with the
134  * port device instead.
135  *
136  * Port drivers can use TYPEC_MODE_AUDIO and TYPEC_MODE_DEBUG as the mode
137  * value for typec_set_mode() when accessory modes are supported.
138  *
139  * USB4 also requires that the pins on the connector are repurposed, just like
140  * Alternate Modes. USB4 mode is however not entered with the Enter Mode Command
141  * like the Alternate Modes are, but instead with a special Enter_USB Message.
142  * The Enter_USB Message can also be used for setting to connector to operate in
143  * USB 3.2 or in USB 2.0 mode instead of USB4.
144  *
145  * The Enter_USB specific "USB Modes" are also supplied here as special modal
146  * state values, just like the Accessory Modes.
147  */
148 enum {
149 	TYPEC_MODE_USB2 = TYPEC_STATE_MODAL,	/* USB 2.0 mode */
150 	TYPEC_MODE_USB3,			/* USB 3.2 mode */
151 	TYPEC_MODE_USB4,			/* USB4 mode */
152 	TYPEC_MODE_AUDIO,			/* Audio Accessory */
153 	TYPEC_MODE_DEBUG,			/* Debug Accessory */
154 };
155 
156 #define TYPEC_MODAL_STATE(_state_)	((_state_) + TYPEC_STATE_MODAL)
157 
158 struct typec_altmode *typec_altmode_get_plug(struct typec_altmode *altmode,
159 					     enum typec_plug_index index);
160 void typec_altmode_put_plug(struct typec_altmode *plug);
161 
162 struct typec_altmode *typec_match_altmode(struct typec_altmode **altmodes,
163 					  size_t n, u16 svid, u8 mode);
164 
165 /**
166  * typec_altmode_get_orientation - Get cable plug orientation
167  * @altmode: Handle to the alternate mode
168  */
169 static inline enum typec_orientation
170 typec_altmode_get_orientation(struct typec_altmode *altmode)
171 {
172 	return typec_get_orientation(typec_altmode2port(altmode));
173 }
174 
175 /**
176  * typec_altmode_get_svdm_version - Get negotiated SVDM version
177  * @altmode: Handle to the alternate mode
178  */
179 static inline int
180 typec_altmode_get_svdm_version(struct typec_altmode *altmode)
181 {
182 	return typec_get_negotiated_svdm_version(typec_altmode2port(altmode));
183 }
184 
185 /**
186  * typec_altmode_get_data_role - Get port data role
187  * @altmode: Handle to the alternate mode
188  *
189  * Alt Mode drivers should only issue Enter Mode through the port if they are
190  * the DFP.
191  */
192 static inline enum typec_data_role
193 typec_altmode_get_data_role(struct typec_altmode *altmode)
194 {
195 	return typec_get_data_role(typec_altmode2port(altmode));
196 }
197 
198 /**
199  * struct typec_altmode_driver - USB Type-C alternate mode device driver
200  * @id_table: Null terminated array of SVIDs
201  * @probe: Callback for device binding
202  * @remove: Callback for device unbinding
203  * @driver: Device driver model driver
204  *
205  * These drivers will be bind to the partner alternate mode devices. They will
206  * handle all SVID specific communication.
207  */
208 struct typec_altmode_driver {
209 	const struct typec_device_id *id_table;
210 	int (*probe)(struct typec_altmode *altmode);
211 	void (*remove)(struct typec_altmode *altmode);
212 	struct device_driver driver;
213 };
214 
215 #define to_altmode_driver(d) container_of(d, struct typec_altmode_driver, \
216 					  driver)
217 
218 /**
219  * typec_altmode_register_driver - registers a USB Type-C alternate mode
220  * 				   device driver
221  * @drv: pointer to struct typec_altmode_driver
222  *
223  * These drivers will be bind to the partner alternate mode devices. They will
224  * handle all SVID specific communication.
225  */
226 #define typec_altmode_register_driver(drv) \
227 		__typec_altmode_register_driver(drv, THIS_MODULE)
228 int __typec_altmode_register_driver(struct typec_altmode_driver *drv,
229 				    struct module *module);
230 /**
231  * typec_altmode_unregister_driver - unregisters a USB Type-C alternate mode
232  * 				     device driver
233  * @drv: pointer to struct typec_altmode_driver
234  *
235  * These drivers will be bind to the partner alternate mode devices. They will
236  * handle all SVID specific communication.
237  */
238 void typec_altmode_unregister_driver(struct typec_altmode_driver *drv);
239 
240 #define module_typec_altmode_driver(__typec_altmode_driver) \
241 	module_driver(__typec_altmode_driver, typec_altmode_register_driver, \
242 		      typec_altmode_unregister_driver)
243 
244 /**
245  * typec_mode_selection_start - Start an alternate mode selection process
246  * @partner: Handle to the Type-C partner device
247  * @delay: Delay between mode entry/exit attempts, ms
248  * @timeout: Timeout for a mode entry attempt, ms
249  *
250  * This function initiates the process of attempting to enter an Alternate Mode
251  * supported by the connected Type-C partner.
252  * Returns 0 on success, or a negative error code on failure.
253  */
254 int typec_mode_selection_start(struct typec_partner *partner,
255 			       const unsigned int delay, const unsigned int timeout);
256 
257 /**
258  * typec_altmode_state_update - Report the current status of an Alternate Mode
259  * negotiation
260  * @partner: Handle to the Type-C partner device
261  * @svid: Standard or Vendor ID of the Alternate Mode. A value of 0 should be
262  * passed if no mode is currently active
263  * @result: Result of the entry operation. This should be 0 on success, or a
264  * negative error code if the negotiation failed
265  *
266  * This function should be called by an Alternate Mode driver to report the
267  * result of an asynchronous alternate mode entry request. It signals what the
268  * current active SVID is (or 0 if none) and the success or failure status of
269  * the last attempt.
270  */
271 void typec_altmode_state_update(struct typec_partner *partner, const u16 svid,
272 				const int result);
273 
274 /**
275  * typec_mode_selection_delete - Delete an alternate mode selection instance
276  * @partner: Handle to the Type-C partner device.
277  *
278  * This function cancels a pending alternate mode selection request that was
279  * previously started with typec_mode_selection_start().
280  * This is typically called when the partner disconnects.
281  */
282 void typec_mode_selection_delete(struct typec_partner *partner);
283 
284 #endif /* __USB_TYPEC_ALTMODE_H */
285