xref: /netbsd-src/sys/dev/usb/usbnet.h (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: usbnet.h,v 1.20 2021/03/01 22:59:52 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 2019 Matthew R. Green
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #ifndef _DEV_USB_USBNET_H
32 #define _DEV_USB_USBNET_H
33 
34 /*
35  * Common code/data shared by all USB ethernet drivers (using these routines.)
36  *
37  * This framework provides the following features for USB ethernet drivers:
38  *
39  * - USB endpoint pipe handling
40  * - rx and tx chain handling
41  * - generic handlers or support for several struct ifnet callbacks
42  * - MII bus locking
43  * - interrupt handling
44  * - partial autoconf handling
45  *
46  * Consumers of this interface need to:
47  *
48  * - replace most softc members with "struct usbnet" usage, in particular
49  *   use usbnet pointer for ifp->if_softc, and device_private (real softc
50  *   can be stored in un_sc member)
51  * - use MII bus lock / access methods
52  * - usbnet_attach() to initialise and allocate rx/tx chains
53  * - usbnet_attach_ifp() to attach the interface, and either ether_ifattach()
54  *   for ethernet devices, or if_alloc_sadl()/bpf_attach() pair otherwise.
55  * - usbnet_detach() to clean them up
56  * - usbnet_activate() for autoconf
57  * - interface ioctl and start have direct frontends with callbacks for
58  *   device specific handling:
59  *   - ioctl can use either a device-specific override (useful for special
60  *     cases), but provides a normal handler with callback to handle
61  *     ENETRESET conditions that should be sufficient for most users
62  *   - start uses usbnet send callback
63  * - interface init and stop have helper functions
64  *   - device specific init should use usbnet_init_rx_tx() to open pipes
65  *     to the device and setup the rx/tx chains for use after any device
66  *     specific setup
67  *   - usbnet_stop() must be called with the un_lock held, and will
68  *     call the device-specific usbnet stop callback, which enables the
69  *     standard init calls stop idiom.
70  * - interrupt handling:
71  *   - for rx, usbnet_init_rx_tx() will enable the receive pipes and
72  *     call the rx_loop callback to handle device specific processing of
73  *     packets, which can use usbnet_enqueue() to provide data to the
74  *     higher layers
75  *   - for tx, usbnet_start (if_start) will pull entries out of the
76  *     transmit queue and use the send callback for the given mbuf.
77  *     the usb callback will use usbnet_txeof() for the transmit
78  *     completion function (internal to usbnet)
79  *   - there is special interrupt pipe handling
80  * - timer/tick:
81  *   - the uno_tick callback will be called once a second if present.
82  */
83 
84 #include <sys/device.h>
85 #include <sys/mbuf.h>
86 #include <sys/rndsource.h>
87 #include <sys/mutex.h>
88 #include <sys/module.h>
89 
90 #include <net/bpf.h>
91 #include <net/if.h>
92 #include <net/if_arp.h>
93 #include <net/if_dl.h>
94 #include <net/if_ether.h>
95 #include <net/if_media.h>
96 
97 #include <dev/mii/mii.h>
98 #include <dev/mii/miivar.h>
99 
100 #include <dev/usb/usb.h>
101 #include <dev/usb/usbdi.h>
102 #include <dev/usb/usbdivar.h>
103 #include <dev/usb/usbdi_util.h>
104 #include <dev/usb/usbdevs.h>
105 
106 /*
107  * Per-transfer data.
108  *
109  * Front-end must set un_rx_list_cnt and un_tx_list_cnt before
110  * calling usbnet_attach(), and then call usbnet_rx_tx_init()
111  * which will allocate the chain arrays, and must be NULL to
112  * indicate the first call.
113  */
114 struct usbnet;
115 struct usbnet_chain {
116 	struct usbnet		*unc_un;
117 	struct usbd_xfer	*unc_xfer;
118 	uint8_t			*unc_buf;
119 };
120 
121 /*
122  * Extend this as necessary.  axe(4) claims to want 6 total, but
123  * does not implement them.
124  */
125 enum usbnet_ep {
126 	USBNET_ENDPT_RX,
127 	USBNET_ENDPT_TX,
128 	USBNET_ENDPT_INTR,
129 	USBNET_ENDPT_MAX,
130 };
131 
132 /* Interface stop callback. */
133 typedef void (*usbnet_stop_cb)(struct ifnet *, int);
134 /* Interface ioctl callback. */
135 typedef int (*usbnet_ioctl_cb)(struct ifnet *, u_long, void *);
136 /* Initialise device callback. */
137 typedef int (*usbnet_init_cb)(struct ifnet *);
138 
139 /* MII read register callback. */
140 typedef int (*usbnet_mii_read_reg_cb)(struct usbnet *, int reg,
141 				      int phy, uint16_t *val);
142 /* MII write register callback. */
143 typedef int (*usbnet_mii_write_reg_cb)(struct usbnet *, int reg,
144 				       int phy, uint16_t val);
145 /* MII status change callback. */
146 typedef void (*usbnet_mii_statchg_cb)(struct ifnet *);
147 
148 /* Prepare packet to send callback, returns length. */
149 typedef unsigned (*usbnet_tx_prepare_cb)(struct usbnet *, struct mbuf *,
150 					 struct usbnet_chain *);
151 /* Receive some packets callback. */
152 typedef void (*usbnet_rx_loop_cb)(struct usbnet *, struct usbnet_chain *,
153 				  uint32_t);
154 /* Tick callback. */
155 typedef void (*usbnet_tick_cb)(struct usbnet *);
156 /* Interrupt pipe callback. */
157 typedef void (*usbnet_intr_cb)(struct usbnet *, usbd_status);
158 
159 /*
160  * LOCKING
161  * =======
162  *
163  * The following annotations indicate which locks are held when
164  * usbnet_ops functions are invoked:
165  *
166  * I -> IFNET_LOCK (if_ioctl_lock)
167  * C -> CORE_LOCK (usbnet core_lock)
168  * T -> TX_LOCK (usbnet tx_lock)
169  * R -> RX_LOCK (usbnet rx_lock)
170  * n -> no locks held
171  *
172  * Note that when CORE_LOCK is held, IFNET_LOCK may or may not also
173  * be held.
174  *
175  * Note that the IFNET_LOCK **may not be held** for some ioctl
176  * operations (add/delete multicast addresses, for example).
177  *
178  * Busy reference counts are maintained across calls to: uno_stop,
179  * uno_read_reg, uno_write_reg, uno_statchg, and uno_tick.
180  */
181 struct usbnet_ops {
182 	usbnet_stop_cb		uno_stop;		/* C */
183 	usbnet_ioctl_cb		uno_ioctl;		/* I (maybe) */
184 	usbnet_ioctl_cb		uno_override_ioctl;	/* I (maybe) */
185 	usbnet_init_cb		uno_init;		/* I */
186 	usbnet_mii_read_reg_cb	uno_read_reg;		/* C */
187 	usbnet_mii_write_reg_cb uno_write_reg;		/* C */
188 	usbnet_mii_statchg_cb	uno_statchg;		/* C */
189 	usbnet_tx_prepare_cb	uno_tx_prepare;		/* T */
190 	usbnet_rx_loop_cb	uno_rx_loop;		/* R */
191 	usbnet_tick_cb		uno_tick;		/* n */
192 	usbnet_intr_cb		uno_intr;		/* n */
193 };
194 
195 /*
196  * USB interrupt pipe support.  Use this if usbd_open_pipe_intr() should
197  * be used for the interrupt pipe.
198  */
199 struct usbnet_intr {
200 	/*
201 	 * Point un_intr to this structure to use usbd_open_pipe_intr() not
202 	 * usbd_open_pipe() for USBNET_ENDPT_INTR, with this buffer, size,
203 	 * and interval.
204 	 */
205 	void			*uni_buf;
206 	unsigned		uni_bufsz;
207 	unsigned		uni_interval;
208 };
209 
210 /*
211  * Structure to setup MII.  Use the USBNET_MII_DECL_DEFAULT() macro for
212  * sane default.  Pass a copy to usbnet_attach_ifp().  Not used
213  * after the usbnet_attach_ifp() function returns.
214  */
215 struct usbnet_mii {
216 	int			un_mii_flags;
217 	int			un_mii_capmask;
218 	int			un_mii_phyloc;
219 	int			un_mii_offset;
220 };
221 
222 #define USBNET_MII_DECL(name, capmask, loc, off, flags)	\
223 	struct usbnet_mii name = {			\
224 		.un_mii_capmask = capmask,		\
225 		.un_mii_phyloc = loc,			\
226 		.un_mii_offset = off,			\
227 		.un_mii_flags = flags,			\
228 	}
229 #define USBNET_MII_DECL_DEFAULT(name)				\
230 	USBNET_MII_DECL(name, 0xffffffff, MII_PHY_ANY, MII_OFFSET_ANY, 0)
231 
232 /*
233  * Generic USB ethernet structure.  Use this as ifp->if_softc and set as
234  * device_private() in attach unless already using struct usbnet here.
235  *
236  * Devices without MII should call usbnet_attach_ifp() with have_mii set
237  * to true, and should ensure that the un_statchg_cb callback sets the
238  * un_link member.  Devices without MII have this forced to true.
239  */
240 struct usbnet_private;
241 struct usbnet {
242 	/*
243 	 * This section should be filled in before calling
244 	 * usbnet_attach().
245 	 */
246 	void			*un_sc;			/* real softc */
247 	device_t		un_dev;
248 	struct usbd_interface	*un_iface;
249 	struct usbd_device	*un_udev;
250 	const struct usbnet_ops	*un_ops;
251 	struct usbnet_intr	*un_intr;
252 
253 	/* Inputs for rx/tx chain control. */
254 	unsigned		un_rx_bufsz;
255 	unsigned		un_tx_bufsz;
256 	unsigned		un_rx_list_cnt;
257 	unsigned		un_tx_list_cnt;
258 	int			un_rx_xfer_flags;
259 	int			un_tx_xfer_flags;
260 
261 	/*
262 	 * This section should be filled in before calling
263 	 * usbnet_attach_ifp().
264 	 *
265 	 * XXX This should be of type "uByte".  enum usbnet_ep
266 	 * is the index.  Fix this in a kernel version bump.
267 	 */
268 	enum usbnet_ep		un_ed[USBNET_ENDPT_MAX];
269 
270 	/* MII specific. Not used without MII. */
271 	int			un_phyno;
272 	/* Ethernet specific. All zeroes indicates non-Ethernet. */
273 	uint8_t			un_eaddr[ETHER_ADDR_LEN];
274 
275 	/*
276 	 * This section is for driver to use, not touched by usbnet.
277 	 */
278 	unsigned		un_flags;
279 
280 	/*
281 	 * This section is private to usbnet. Don't touch.
282 	 */
283 	struct usbnet_private	*un_pri;
284 };
285 
286 /* Various accessors. */
287 
288 void usbnet_set_link(struct usbnet *, bool);
289 void usbnet_set_dying(struct usbnet *, bool);
290 
291 struct ifnet *usbnet_ifp(struct usbnet *);
292 struct ethercom *usbnet_ec(struct usbnet *);
293 struct mii_data *usbnet_mii(struct usbnet *);
294 krndsource_t *usbnet_rndsrc(struct usbnet *);
295 void *usbnet_softc(struct usbnet *);
296 
297 bool usbnet_havelink(struct usbnet *);
298 bool usbnet_isdying(struct usbnet *);
299 
300 
301 /*
302  * Locking.  Note that the isowned() are implemented here so that
303  * empty-KASSERT() causes them to be elided for non-DIAG builds.
304  */
305 void	usbnet_lock_core(struct usbnet *);
306 void	usbnet_unlock_core(struct usbnet *);
307 kmutex_t *usbnet_mutex_core(struct usbnet *);
308 static __inline__ void
309 usbnet_isowned_core(struct usbnet *un)
310 {
311 	KASSERT(mutex_owned(usbnet_mutex_core(un)));
312 }
313 
314 void	usbnet_busy(struct usbnet *);
315 void	usbnet_unbusy(struct usbnet *);
316 
317 void	usbnet_lock_rx(struct usbnet *);
318 void	usbnet_unlock_rx(struct usbnet *);
319 kmutex_t *usbnet_mutex_rx(struct usbnet *);
320 static __inline__ void
321 usbnet_isowned_rx(struct usbnet *un)
322 {
323 	KASSERT(mutex_owned(usbnet_mutex_rx(un)));
324 }
325 
326 void	usbnet_lock_tx(struct usbnet *);
327 void	usbnet_unlock_tx(struct usbnet *);
328 kmutex_t *usbnet_mutex_tx(struct usbnet *);
329 static __inline__ void
330 usbnet_isowned_tx(struct usbnet *un)
331 {
332 	KASSERT(mutex_owned(usbnet_mutex_tx(un)));
333 }
334 
335 /*
336  * Endpoint / rx/tx chain management:
337  *
338  * usbnet_attach() initialises usbnet and allocates rx and tx chains
339  * usbnet_init_rx_tx() open pipes, initialises the rx/tx chains for use
340  * usbnet_stop() stops pipes, cleans (not frees) rx/tx chains, locked
341  *               version assumes un_lock is held
342  * usbnet_detach() frees the rx/tx chains
343  *
344  * Setup un_ed[] with valid end points before calling usbnet_attach().
345  * Call usbnet_init_rx_tx() to initialise pipes, which will be open
346  * upon success.
347  */
348 int	usbnet_init_rx_tx(struct usbnet * const);
349 
350 /* MII. */
351 int	usbnet_mii_readreg(device_t, int, int, uint16_t *);
352 int	usbnet_mii_writereg(device_t, int, int, uint16_t);
353 void	usbnet_mii_statchg(struct ifnet *);
354 
355 /* interrupt handling */
356 void	usbnet_enqueue(struct usbnet * const, uint8_t *, size_t, int,
357 		       uint32_t, int);
358 void	usbnet_input(struct usbnet * const, uint8_t *, size_t);
359 
360 /* autoconf */
361 void	usbnet_attach(struct usbnet *un, const char *);
362 void	usbnet_attach_ifp(struct usbnet *, unsigned, unsigned,
363 			  const struct usbnet_mii *);
364 int	usbnet_detach(device_t, int);
365 int	usbnet_activate(device_t, devact_t);
366 
367 /* stop backend */
368 void	usbnet_stop(struct usbnet *, struct ifnet *, int);
369 
370 /* module hook up */
371 
372 #ifdef _MODULE
373 #define USBNET_INIT(name)						\
374 	error = config_init_component(cfdriver_ioconf_##name,		\
375 	    cfattach_ioconf_##name, cfdata_ioconf_##name);
376 #define USBNET_FINI(name)						\
377 	error = config_fini_component(cfdriver_ioconf_##name,		\
378 	    cfattach_ioconf_##name, cfdata_ioconf_##name);
379 #else
380 #define USBNET_INIT(name)
381 #define USBNET_FINI(name)
382 #endif
383 
384 #define USBNET_MODULE(name)						\
385 									\
386 MODULE(MODULE_CLASS_DRIVER, if_##name, "usbnet");			\
387 									\
388 static int								\
389 if_##name##_modcmd(modcmd_t cmd, void *aux)				\
390 {									\
391 	int error = 0;							\
392 									\
393 	switch (cmd) {							\
394 	case MODULE_CMD_INIT:						\
395 		USBNET_INIT(name)					\
396 		return error;						\
397 	case MODULE_CMD_FINI:						\
398 		USBNET_FINI(name)					\
399 		return error;						\
400 	default:							\
401 		return ENOTTY;						\
402 	}								\
403 }
404 
405 #endif /* _DEV_USB_USBNET_H */
406