alistair23-linux/include/uapi/linux/pg.h
Greg Kroah-Hartman e2be04c7f9 License cleanup: add SPDX license identifier to uapi header files with a license
Many user space API headers have licensing information, which is either
incomplete, badly formatted or just a shorthand for referring to the
license under which the file is supposed to be.  This makes it hard for
compliance tools to determine the correct license.

Update these files with an SPDX license identifier.  The identifier was
chosen based on the license information in the file.

GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license
identifier with the added 'WITH Linux-syscall-note' exception, which is
the officially assigned exception identifier for the kernel syscall
exception:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

This exception makes it possible to include GPL headers into non GPL
code, without confusing license compliance tools.

Headers which have either explicit dual licensing or are just licensed
under a non GPL license are updated with the corresponding SPDX
identifier and the GPLv2 with syscall exception identifier.  The format
is:
        ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE)

SPDX license identifiers are a legally binding shorthand, which can be
used instead of the full boiler plate text.  The update does not remove
existing license information as this has to be done on a case by case
basis and the copyright holders might have to be consulted. This will
happen in a separate step.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:20:11 +01:00

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C

/* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */
/* pg.h (c) 1998 Grant R. Guenther <grant@torque.net>
Under the terms of the GNU General Public License
pg.h defines the user interface to the generic ATAPI packet
command driver for parallel port ATAPI devices (pg). The
driver is loosely modelled after the generic SCSI driver, sg,
although the actual interface is different.
The pg driver provides a simple character device interface for
sending ATAPI commands to a device. With the exception of the
ATAPI reset operation, all operations are performed by a pair
of read and write operations to the appropriate /dev/pgN device.
A write operation delivers a command and any outbound data in
a single buffer. Normally, the write will succeed unless the
device is offline or malfunctioning, or there is already another
command pending. If the write succeeds, it should be followed
immediately by a read operation, to obtain any returned data and
status information. A read will fail if there is no operation
in progress.
As a special case, the device can be reset with a write operation,
and in this case, no following read is expected, or permitted.
There are no ioctl() operations. Any single operation
may transfer at most PG_MAX_DATA bytes. Note that the driver must
copy the data through an internal buffer. In keeping with all
current ATAPI devices, command packets are assumed to be exactly
12 bytes in length.
To permit future changes to this interface, the headers in the
read and write buffers contain a single character "magic" flag.
Currently this flag must be the character "P".
*/
#define PG_MAGIC 'P'
#define PG_RESET 'Z'
#define PG_COMMAND 'C'
#define PG_MAX_DATA 32768
struct pg_write_hdr {
char magic; /* == PG_MAGIC */
char func; /* PG_RESET or PG_COMMAND */
int dlen; /* number of bytes expected to transfer */
int timeout; /* number of seconds before timeout */
char packet[12]; /* packet command */
};
struct pg_read_hdr {
char magic; /* == PG_MAGIC */
char scsi; /* "scsi" status == sense key */
int dlen; /* size of device transfer request */
int duration; /* time in seconds command took */
char pad[12]; /* not used */
};
/* end of pg.h */