xref: /openbmc/linux/drivers/usb/storage/usb.h (revision cfbb9be8)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for USB Mass Storage compliant devices
4  * Main Header File
5  *
6  * Current development and maintenance by:
7  *   (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
8  *
9  * Initial work by:
10  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
11  *
12  * This driver is based on the 'USB Mass Storage Class' document. This
13  * describes in detail the protocol used to communicate with such
14  * devices.  Clearly, the designers had SCSI and ATAPI commands in
15  * mind when they created this document.  The commands are all very
16  * similar to commands in the SCSI-II and ATAPI specifications.
17  *
18  * It is important to note that in a number of cases this class
19  * exhibits class-specific exemptions from the USB specification.
20  * Notably the usage of NAK, STALL and ACK differs from the norm, in
21  * that they are used to communicate wait, failed and OK on commands.
22  *
23  * Also, for certain devices, the interrupt endpoint is used to convey
24  * status of a command.
25  */
26 
27 #ifndef _USB_H_
28 #define _USB_H_
29 
30 #include <linux/usb.h>
31 #include <linux/usb_usual.h>
32 #include <linux/blkdev.h>
33 #include <linux/completion.h>
34 #include <linux/mutex.h>
35 #include <linux/workqueue.h>
36 #include <scsi/scsi_host.h>
37 
38 struct us_data;
39 struct scsi_cmnd;
40 
41 /*
42  * Unusual device list definitions
43  */
44 
45 struct us_unusual_dev {
46 	const char* vendorName;
47 	const char* productName;
48 	__u8  useProtocol;
49 	__u8  useTransport;
50 	int (*initFunction)(struct us_data *);
51 };
52 
53 
54 /* Dynamic bitflag definitions (us->dflags): used in set_bit() etc. */
55 #define US_FLIDX_URB_ACTIVE	0	/* current_urb is in use    */
56 #define US_FLIDX_SG_ACTIVE	1	/* current_sg is in use     */
57 #define US_FLIDX_ABORTING	2	/* abort is in progress     */
58 #define US_FLIDX_DISCONNECTING	3	/* disconnect in progress   */
59 #define US_FLIDX_RESETTING	4	/* device reset in progress */
60 #define US_FLIDX_TIMED_OUT	5	/* SCSI midlayer timed out  */
61 #define US_FLIDX_SCAN_PENDING	6	/* scanning not yet done    */
62 #define US_FLIDX_REDO_READ10	7	/* redo READ(10) command    */
63 #define US_FLIDX_READ10_WORKED	8	/* previous READ(10) succeeded */
64 
65 #define USB_STOR_STRING_LEN 32
66 
67 /*
68  * We provide a DMA-mapped I/O buffer for use with small USB transfers.
69  * It turns out that CB[I] needs a 12-byte buffer and Bulk-only needs a
70  * 31-byte buffer.  But Freecom needs a 64-byte buffer, so that's the
71  * size we'll allocate.
72  */
73 
74 #define US_IOBUF_SIZE		64	/* Size of the DMA-mapped I/O buffer */
75 #define US_SENSE_SIZE		18	/* Size of the autosense data buffer */
76 
77 typedef int (*trans_cmnd)(struct scsi_cmnd *, struct us_data*);
78 typedef int (*trans_reset)(struct us_data*);
79 typedef void (*proto_cmnd)(struct scsi_cmnd*, struct us_data*);
80 typedef void (*extra_data_destructor)(void *);	/* extra data destructor */
81 typedef void (*pm_hook)(struct us_data *, int);	/* power management hook */
82 
83 #define US_SUSPEND	0
84 #define US_RESUME	1
85 
86 /* we allocate one of these for every device that we remember */
87 struct us_data {
88 	/*
89 	 * The device we're working with
90 	 * It's important to note:
91 	 *    (o) you must hold dev_mutex to change pusb_dev
92 	 */
93 	struct mutex		dev_mutex;	 /* protect pusb_dev */
94 	struct usb_device	*pusb_dev;	 /* this usb_device */
95 	struct usb_interface	*pusb_intf;	 /* this interface */
96 	struct us_unusual_dev   *unusual_dev;	 /* device-filter entry     */
97 	unsigned long		fflags;		 /* fixed flags from filter */
98 	unsigned long		dflags;		 /* dynamic atomic bitflags */
99 	unsigned int		send_bulk_pipe;	 /* cached pipe values */
100 	unsigned int		recv_bulk_pipe;
101 	unsigned int		send_ctrl_pipe;
102 	unsigned int		recv_ctrl_pipe;
103 	unsigned int		recv_intr_pipe;
104 
105 	/* information about the device */
106 	char			*transport_name;
107 	char			*protocol_name;
108 	__le32			bcs_signature;
109 	u8			subclass;
110 	u8			protocol;
111 	u8			max_lun;
112 
113 	u8			ifnum;		 /* interface number   */
114 	u8			ep_bInterval;	 /* interrupt interval */
115 
116 	/* function pointers for this device */
117 	trans_cmnd		transport;	 /* transport function	   */
118 	trans_reset		transport_reset; /* transport device reset */
119 	proto_cmnd		proto_handler;	 /* protocol handler	   */
120 
121 	/* SCSI interfaces */
122 	struct scsi_cmnd	*srb;		 /* current srb		*/
123 	unsigned int		tag;		 /* current dCBWTag	*/
124 	char			scsi_name[32];	 /* scsi_host name	*/
125 
126 	/* control and bulk communications data */
127 	struct urb		*current_urb;	 /* USB requests	 */
128 	struct usb_ctrlrequest	*cr;		 /* control requests	 */
129 	struct usb_sg_request	current_sg;	 /* scatter-gather req.  */
130 	unsigned char		*iobuf;		 /* I/O buffer		 */
131 	dma_addr_t		iobuf_dma;	 /* buffer DMA addresses */
132 	struct task_struct	*ctl_thread;	 /* the control thread   */
133 
134 	/* mutual exclusion and synchronization structures */
135 	struct completion	cmnd_ready;	 /* to sleep thread on	    */
136 	struct completion	notify;		 /* thread begin/end	    */
137 	wait_queue_head_t	delay_wait;	 /* wait during reset	    */
138 	struct delayed_work	scan_dwork;	 /* for async scanning      */
139 
140 	/* subdriver information */
141 	void			*extra;		 /* Any extra data          */
142 	extra_data_destructor	extra_destructor;/* extra data destructor   */
143 #ifdef CONFIG_PM
144 	pm_hook			suspend_resume_hook;
145 #endif
146 
147 	/* hacks for READ CAPACITY bug handling */
148 	int			use_last_sector_hacks;
149 	int			last_sector_retries;
150 };
151 
152 /* Convert between us_data and the corresponding Scsi_Host */
153 static inline struct Scsi_Host *us_to_host(struct us_data *us) {
154 	return container_of((void *) us, struct Scsi_Host, hostdata);
155 }
156 static inline struct us_data *host_to_us(struct Scsi_Host *host) {
157 	return (struct us_data *) host->hostdata;
158 }
159 
160 /* Function to fill an inquiry response. See usb.c for details */
161 extern void fill_inquiry_response(struct us_data *us,
162 	unsigned char *data, unsigned int data_len);
163 
164 /*
165  * The scsi_lock() and scsi_unlock() macros protect the sm_state and the
166  * single queue element srb for write access
167  */
168 #define scsi_unlock(host)	spin_unlock_irq(host->host_lock)
169 #define scsi_lock(host)		spin_lock_irq(host->host_lock)
170 
171 /* General routines provided by the usb-storage standard core */
172 #ifdef CONFIG_PM
173 extern int usb_stor_suspend(struct usb_interface *iface, pm_message_t message);
174 extern int usb_stor_resume(struct usb_interface *iface);
175 extern int usb_stor_reset_resume(struct usb_interface *iface);
176 #else
177 #define usb_stor_suspend	NULL
178 #define usb_stor_resume		NULL
179 #define usb_stor_reset_resume	NULL
180 #endif
181 
182 extern int usb_stor_pre_reset(struct usb_interface *iface);
183 extern int usb_stor_post_reset(struct usb_interface *iface);
184 
185 extern int usb_stor_probe1(struct us_data **pus,
186 		struct usb_interface *intf,
187 		const struct usb_device_id *id,
188 		struct us_unusual_dev *unusual_dev,
189 		struct scsi_host_template *sht);
190 extern int usb_stor_probe2(struct us_data *us);
191 extern void usb_stor_disconnect(struct usb_interface *intf);
192 
193 extern void usb_stor_adjust_quirks(struct usb_device *dev,
194 		unsigned long *fflags);
195 
196 #define module_usb_stor_driver(__driver, __sht, __name) \
197 static int __init __driver##_init(void) \
198 { \
199 	usb_stor_host_template_init(&(__sht), __name, THIS_MODULE); \
200 	return usb_register(&(__driver)); \
201 } \
202 module_init(__driver##_init); \
203 static void __exit __driver##_exit(void) \
204 { \
205 	usb_deregister(&(__driver)); \
206 } \
207 module_exit(__driver##_exit)
208 
209 #endif
210