illumos: manual page: usbprn.4d

USBPRN(4D) Devices USBPRN(4D)

NAME

usbprn - USB printer class driver

SYNOPSIS

#include <sys/usb/clients/printer/usb_printer.h>

#include <sys/ecppio.h>

usbprn@unit-address

DESCRIPTION

The usbprn driver is a USBA (Solaris USB Architecture) compliant client
driver that supports the USB Printer Class 1.0 specification. The usbprn
driver supports a subset of the ecpp(4D) parallel port driver
functionality. However, unlike the STREAMS-based ecpp driver, usbprn is a
character driver.

The usbprn driver supports all USB printer-class compliant printers.

The usbrpn driver includes support for communicating with many different
printers. To use these printers, it may be necessary to install and
configure additional format conversion packages.

UGEN (Generic USB)
The usbprn driver also supports a ugen(4D) interface allowing raw access
to the device, for example by libusb applications, by passing the drivers
bound to each interface. Because a libusb application might change the
state of the device, you should not access the device through the child
interface drivers.

DEFAULT OPERATION

With certain minor exceptions (outlined in the Notes sections below), the
usbprn driver supports a subset of the ecpp(4D) ioctl interfaces:

Configuration variables are set to their default values each time the USB
printer device is attached. The write_timeout period (defined in the
ECPPIOC_SETPARMS ioctl description below) is set to 90 seconds. The mode
is set to centronics mode (ECPP_CENTRONICS). Parameters can be changed
through the ECPPIOC_SETPARMS ioctl and read through the ECPPIOC_GETPARMS
ioctl. Each time the USB printer device is opened, the device is marked
as busy and all further opens will return EBUSY. Once the device is open,
applications can write to the device and the driver can send data and
obtain device id and status.

Note -

Unlike the ecpp(4D) driver, usbprn resets configuration variables to
their default values with each attach(9E). (The ecpp(4D) driver resets
configuration variables with each open(2).)

WRITE OPERATION

A write(2) operation returns the number of bytes successfully written to
the device. If a failure occurs while a driver is transferring data to
printer, the contents of the status bits are captured at the time of the
error and can be retrieved by the application program using the
ECPPIOC_GETERR ioctl(2) call. The captured status information is
overwritten each time an ECPPIOC_TESTIO ioctl(2) occurs.

IOCTLS

The usbprn driver supports prnio(4I) interfaces. Note that the
PRNIOC_RESET command has no effect on USB printers.

The following ioctl(2) calls are supported for backward compatibility and
are not recommended for new applications.

ECPPIOC_GETPARMS
Gets current transfer parameters. The argument is a
pointer to struct ecpp_transfer_parms. If parameters
are not configured after the device is opened, the
structure will be set to its default configuration.

Note -

Unlike the ecpp(4D) driver, only the
ECPP_CENTRONICS mode is currently supported in
usbprn.

ECPPIOC_SETPARMS
Sets transfer parameters. The argument is a pointer
to a struct ecpp_transfer_parms. If a parameter is
out of range, EINVAL is returned. If the peripheral
or host device cannot support the requested mode,
EPROTONOSUPPORT is returned.

The transfer parameters structure is defined in
<sys/ecppio.h>:

struct ecpp_transfer_parms {
int write_timeout;
int mode;
};

The write_timeout field, which specifies how long the
driver will take to transfer 8192 bytes of data to
the device, is set to a default value of 90 seconds.
The write_timeout field must be greater than one
second and less than 300 seconds (five minutes.)

Note -

Unlike the ecpp(4D) driver, only the
ECPP_CENTRONICS mode is currently supported in
usbprn. Also, the semantics of write_timeout in
usbprn differ from ecpp(4D). Refer to ecpp(4D) for
information.

BPPIOC_TESTIO
Tests the transfer readiness of a print device and
checks status bits to determine if a write(2) will
succeed. If status bits are set, a transfer will
fail. If a transfer will succeed, zero is returned.
If a transfer fails, the driver returns EIO and the
state of the status bits are captured. The captured
status can be retrieved using the BPPIOC_GETERR
ioctl(2) call.

Note -

Unlike the ecpp(4D) driver, only the
ECPP_CENTRONICS mode is currently supported in
usbprn. Additionally, bus_error and
timeout_occurred fields are not used in the usbprn
interface. (In ecpp(4D), timeout_occurred is used.)

BPPIOC_GETERR
Get last error status. The argument is a pointer to a
struct bpp_error_status. This structure indicates the
status of all the appropriate status bits at the time
of the most recent error condition during a write(2)
call, or the status of the bits at the most recent
BPPIOC_TESTIO ioctl(2) call.

struct bpp_error_status {
char timeout_occurred; /* not used */
char bus_error; /* not used */
uchar_t pin_status; /* status of pins which
/* could cause error */
};

The pin_status field indicates possible error
conditions. The error status structure
bpp_error_status is defined in the include file
<sys/bpp_io.h>. The valid bits for pin_status can be
BPP_ERR_ERR, BPP_SLCT_ERR, and BPP_PE_ERR. A set bit
indicates that the associated pin is asserted.

Note -

Unlike the ecpp(4D) driver, only the
ECPP_CENTRONICS mode is currently supported in
usbprn. Additionally, the bus_error and
timeout_occurred fields are not used in the usbprn
interface. (In ecpp(4D), timeout_occurred is used.)
Unlike ecpp(4D), the BPP_BUSY_ERR status bit is not
supported by USB printers.

ECPPIOC_GETDEVID
Gets the IEEE 1284 device ID from the peripheral. The
argument is a pointer to a struct ecpp_device_id.
Applications should set mode to ECPP_CENTRONICS. If
another mode is used, the driver will return
EPROTONOSUPPORT. len is the length of the buffer
pointed to by addr. rlen is the actual length of the
device ID string returned from the peripheral. If the
returned rlen is greater than len, the application
should call ECPPIOC_GETDEVID a second time with a
buffer length equal to rlen.

The 1284 device ID structure:

struct ecpp_device_id {
int mode; /* mode to use for reading device id */
int len; /* length of buffer */
int rlen; /* actual length of device id string */
char *addr; /* buffer address */

Note -

Unlike ecpp(4D), only the ECPP_CENTRONICS mode is
currently supported in usbprn.

READ OPERATION

The read operation is not supported and returns EIO.

ERRORS

EBUSY
The device has been opened and another open is
attempted. An attempt has been made to unload the
driver while one of the units is open.

EINVAL
An unsupported IOCTL has been received. A
ECPPIOC_SETPARMS ioctl(2) is attempted with an out of
range value in the ecpp_transfer_parms structure.

EIO
The driver has received an unrecoverable device error,
or the device is not responding, or the device has
stalled when attempting an access. A write(2) or
ioctl(2) did not complete due to a peripheral access.
A read(2) system call has been issued.

ENXIO
The driver has received an open(2) request for a unit
for which the attach failed.

ENODEV
The driver has received an open(2) request for a
device that has been disconnected.

EPROTONOSUPPORT
The driver has received a ECPPIOC_SETPARMS ioctl(2)
for a mode argument other than ECPP_CENTRONICS in the
ecpp_transfer_parms structure.

FILES

/kernel/drv/usbprn
32-bit x86 ELF kernel module

/kernel/drv/amd64/usbprn
64-bit x86 ELF kernel module

/kernel/drv/sparcv9/usbprn
64-bit SPARC ELF kernel module

/dev/usb/*/*/*
ugen(4D) nodes.

/dev/printers/n
Character special files

ATTRIBUTES

DIAGNOSTICS

In addition to being logged, the following messages may appear on the
system console. All messages are formatted in the following manner:

Warning: <device path> (usbprn<instance num>): Error Message...

Device was disconnected while open. Data may have been lost.

The device has been hot-removed or powered off while it was open and
a possible data transfer was in progress. The job may be aborted.

Cannot access <device>. Please reconnect.

There was an error in accessing the printer during reconnect. Please
reconnect the device.

Device is not identical to the previous one on this port. Please
disconnect and reconnect.

A USB printer was hot-removed while open. A new device was hot-
inserted which is not identical to the original USB printer. Please
disconnect the USB device and reconnect the printer to the same port.

Printer has been reconnected but data may have been lost.

The printer that was hot-removed from its USB port has been re-
inserted again to the same port. It is available for access but the
job that was running prior to the hot-removal may be lost.

NOTES

The USB printer will be power managed if the device is closed.

If a printer is hot-removed before a job completes, the job is terminated
and the driver will return EIO. All subsequent opens will return ENODEV.
If a printer is hot-removed, an LP reconfiguration may not be needed if a
printer is re-inserted on the same port. If re-inserted on a different
port, an LP reconfiguration may be required.

The USB Parallel Printer Adapter is not hotpluggable. The printer should
be connected to USB Parallel Printer Adapter before plugging the USB
cable into host or hub port and should be removed only after
disconnecting the USB cable of USB Parallel Printer Adapter from the host
or hub port.

March 12, 2023 USBPRN(4D)