1 // SPDX-License-Identifier: GPL-2.0+
3 * Driver for USB Mass Storage compliant devices
6 * Current development and maintenance by:
7 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
10 * (c) 1999 Michael Gee (michael@linuxspecific.com)
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.
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.
23 * Also, for certain devices, the interrupt endpoint is used to convey
24 * status of a command.
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>
42 * Unusual device list definitions
45 struct us_unusual_dev {
46 const char* vendorName;
47 const char* productName;
50 int (*initFunction)(struct us_data *);
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 */
65 #define USB_STOR_STRING_LEN 32
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.
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 */
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 */
86 /* we allocate one of these for every device that we remember */
89 * The device we're working with
90 * It's important to note:
91 * (o) you must hold dev_mutex to change pusb_dev
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 const struct us_unusual_dev *unusual_dev;
97 /* device-filter entry */
98 unsigned long fflags; /* fixed flags from filter */
99 unsigned long dflags; /* dynamic atomic bitflags */
100 unsigned int send_bulk_pipe; /* cached pipe values */
101 unsigned int recv_bulk_pipe;
102 unsigned int send_ctrl_pipe;
103 unsigned int recv_ctrl_pipe;
104 unsigned int recv_intr_pipe;
106 /* information about the device */
107 char *transport_name;
109 __le32 bcs_signature;
114 u8 ifnum; /* interface number */
115 u8 ep_bInterval; /* interrupt interval */
117 /* function pointers for this device */
118 trans_cmnd transport; /* transport function */
119 trans_reset transport_reset; /* transport device reset */
120 proto_cmnd proto_handler; /* protocol handler */
122 /* SCSI interfaces */
123 struct scsi_cmnd *srb; /* current srb */
124 unsigned int tag; /* current dCBWTag */
125 char scsi_name[32]; /* scsi_host name */
127 /* control and bulk communications data */
128 struct urb *current_urb; /* USB requests */
129 struct usb_ctrlrequest *cr; /* control requests */
130 struct usb_sg_request current_sg; /* scatter-gather req. */
131 unsigned char *iobuf; /* I/O buffer */
132 dma_addr_t iobuf_dma; /* buffer DMA addresses */
133 struct task_struct *ctl_thread; /* the control thread */
135 /* mutual exclusion and synchronization structures */
136 struct completion cmnd_ready; /* to sleep thread on */
137 struct completion notify; /* thread begin/end */
138 wait_queue_head_t delay_wait; /* wait during reset */
139 struct delayed_work scan_dwork; /* for async scanning */
141 /* subdriver information */
142 void *extra; /* Any extra data */
143 extra_data_destructor extra_destructor;/* extra data destructor */
145 pm_hook suspend_resume_hook;
148 /* hacks for READ CAPACITY bug handling */
149 int use_last_sector_hacks;
150 int last_sector_retries;
153 /* Convert between us_data and the corresponding Scsi_Host */
154 static inline struct Scsi_Host *us_to_host(struct us_data *us) {
155 return container_of((void *) us, struct Scsi_Host, hostdata);
157 static inline struct us_data *host_to_us(struct Scsi_Host *host) {
158 return (struct us_data *) host->hostdata;
161 /* Function to fill an inquiry response. See usb.c for details */
162 extern void fill_inquiry_response(struct us_data *us,
163 unsigned char *data, unsigned int data_len);
166 * The scsi_lock() and scsi_unlock() macros protect the sm_state and the
167 * single queue element srb for write access
169 #define scsi_unlock(host) spin_unlock_irq(host->host_lock)
170 #define scsi_lock(host) spin_lock_irq(host->host_lock)
172 /* General routines provided by the usb-storage standard core */
174 extern int usb_stor_suspend(struct usb_interface *iface, pm_message_t message);
175 extern int usb_stor_resume(struct usb_interface *iface);
176 extern int usb_stor_reset_resume(struct usb_interface *iface);
178 #define usb_stor_suspend NULL
179 #define usb_stor_resume NULL
180 #define usb_stor_reset_resume NULL
183 extern int usb_stor_pre_reset(struct usb_interface *iface);
184 extern int usb_stor_post_reset(struct usb_interface *iface);
186 extern int usb_stor_probe1(struct us_data **pus,
187 struct usb_interface *intf,
188 const struct usb_device_id *id,
189 const struct us_unusual_dev *unusual_dev,
190 struct scsi_host_template *sht);
191 extern int usb_stor_probe2(struct us_data *us);
192 extern void usb_stor_disconnect(struct usb_interface *intf);
194 extern void usb_stor_adjust_quirks(struct usb_device *dev,
195 unsigned long *fflags);
197 #define module_usb_stor_driver(__driver, __sht, __name) \
198 static int __init __driver##_init(void) \
200 usb_stor_host_template_init(&(__sht), __name, THIS_MODULE); \
201 return usb_register(&(__driver)); \
203 module_init(__driver##_init); \
204 static void __exit __driver##_exit(void) \
206 usb_deregister(&(__driver)); \
208 module_exit(__driver##_exit)