1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *
4  * Includes for cdc-acm.c
5  *
6  * Mainly take from usbnet's cdc-ether part
7  *
8  */
9 
10 /*
11  * Major and minor numbers.
12  */
13 
14 #define ACM_TTY_MAJOR		166
15 #define ACM_TTY_MINORS		256
16 
17 #define ACM_MINOR_INVALID	ACM_TTY_MINORS
18 
19 /*
20  * Requests.
21  */
22 
23 #define USB_RT_ACM		(USB_TYPE_CLASS | USB_RECIP_INTERFACE)
24 
25 /*
26  * Internal driver structures.
27  */
28 
29 /*
30  * The only reason to have several buffers is to accommodate assumptions
31  * in line disciplines. They ask for empty space amount, receive our URB size,
32  * and proceed to issue several 1-character writes, assuming they will fit.
33  * The very first write takes a complete URB. Fortunately, this only happens
34  * when processing onlcr, so we only need 2 buffers. These values must be
35  * powers of 2.
36  */
37 #define ACM_NW  16
38 #define ACM_NR  16
39 
40 struct acm_wb {
41 	u8 *buf;
42 	dma_addr_t dmah;
43 	unsigned int len;
44 	struct urb		*urb;
45 	struct acm		*instance;
46 	bool use;
47 };
48 
49 struct acm_rb {
50 	int			size;
51 	unsigned char		*base;
52 	dma_addr_t		dma;
53 	int			index;
54 	struct acm		*instance;
55 };
56 
57 struct acm {
58 	struct usb_device *dev;				/* the corresponding usb device */
59 	struct usb_interface *control;			/* control interface */
60 	struct usb_interface *data;			/* data interface */
61 	unsigned in, out;				/* i/o pipes */
62 	struct tty_port port;			 	/* our tty port data */
63 	struct urb *ctrlurb;				/* urbs */
64 	u8 *ctrl_buffer;				/* buffers of urbs */
65 	dma_addr_t ctrl_dma;				/* dma handles of buffers */
66 	u8 *country_codes;				/* country codes from device */
67 	unsigned int country_code_size;			/* size of this buffer */
68 	unsigned int country_rel_date;			/* release date of version */
69 	struct acm_wb wb[ACM_NW];
70 	unsigned long read_urbs_free;
71 	struct urb *read_urbs[ACM_NR];
72 	struct acm_rb read_buffers[ACM_NR];
73 	int rx_buflimit;
74 	spinlock_t read_lock;
75 	u8 *notification_buffer;			/* to reassemble fragmented notifications */
76 	unsigned int nb_index;
77 	unsigned int nb_size;
78 	int transmitting;
79 	spinlock_t write_lock;
80 	struct mutex mutex;
81 	bool disconnected;
82 	unsigned long flags;
83 #		define EVENT_TTY_WAKEUP	0
84 #		define EVENT_RX_STALL	1
85 #		define ACM_THROTTLED	2
86 #		define ACM_ERROR_DELAY	3
87 	unsigned long urbs_in_error_delay;		/* these need to be restarted after a delay */
88 	struct usb_cdc_line_coding line;		/* bits, stop, parity */
89 	struct delayed_work dwork;		        /* work queue entry for various purposes */
90 	unsigned int ctrlin;				/* input control lines (DCD, DSR, RI, break, overruns) */
91 	unsigned int ctrlout;				/* output control lines (DTR, RTS) */
92 	struct async_icount iocount;			/* counters for control line changes */
93 	struct async_icount oldcount;			/* for comparison of counter */
94 	wait_queue_head_t wioctl;			/* for ioctl */
95 	unsigned int writesize;				/* max packet size for the output bulk endpoint */
96 	unsigned int readsize,ctrlsize;			/* buffer sizes for freeing */
97 	unsigned int minor;				/* acm minor number */
98 	unsigned char clocal;				/* termios CLOCAL */
99 	unsigned int ctrl_caps;				/* control capabilities from the class specific header */
100 	unsigned int susp_count;			/* number of suspended interfaces */
101 	unsigned int combined_interfaces:1;		/* control and data collapsed */
102 	u8 bInterval;
103 	struct usb_anchor delayed;			/* writes queued for a device about to be woken */
104 	unsigned long quirks;
105 };
106 
107 /* constants describing various quirks and errors */
108 #define NO_UNION_NORMAL			BIT(0)
109 #define SINGLE_RX_URB			BIT(1)
110 #define NO_CAP_LINE			BIT(2)
111 #define IGNORE_DEVICE			BIT(3)
112 #define QUIRK_CONTROL_LINE_STATE	BIT(4)
113 #define CLEAR_HALT_CONDITIONS		BIT(5)
114 #define SEND_ZERO_PACKET		BIT(6)
115 #define DISABLE_ECHO			BIT(7)
116