Documentation/usb/gadget_printer.rst

14 This driver may be used if you are writing printer firmware using Linux as
15 the embedded OS. This driver has nothing to do with using a printer with
20 USB device controller driver is loaded then load the printer gadget driver.
21 This will present a printer interface to the USB Host that your USB Device
24 This driver is structured for printer firmware that runs in user mode. The
25 user mode printer firmware will read and write data from the kernel mode
26 printer gadget driver using a device file. The printer returns a printer status
27 byte when the USB HOST sends a device request to get the printer status.  The
37 To load the USB device controller driver and the printer gadget driver. The
44 The follow command line parameter can be used when loading the printer gadget
75 	The PNP ID string used for this printer. You will want to set
77 	your printer product.
101 To read printer data from the host to stdout::
106 To write printer data from a file (data_file) to the host::
111 To get the current printer status for the gadget driver:::
121 To set printer to Selected/On-line::
126 To set printer to Not Selected/Off-line::
141 To set error status to printer OK::
186 	fputs("-get_status    Get the current printer status.\n", stderr);
195 	fputs("-read_data     Read printer data from driver.\n", stderr);
196 	fputs("-write_data    Write printer sata to driver.\n", stderr);
197 	fputs("-NB_read_data  (Non-Blocking) Read printer data from driver.\n",
210 	/* Open device file for printer gadget. */
230 			/* Read data from printer gadget driver. */
260 	/* Open device file for printer gadget. */
285 			/* Write data to printer gadget driver. */
321 	/* Open device file for printer gadget. */
330 		/* Read data from printer gadget driver. */
354 	/* Open device file for printer gadget. */
365 		fprintf(stderr, "ERROR: Failed to set printer status\n");
384 		fprintf(stderr, "ERROR: Failed to get printer status\n");
388 	/* Open device file for printer gadget. */
405 		fprintf(stderr, "ERROR: Failed to set printer status\n");
423 		fprintf(stderr, "ERROR: Failed to get printer status\n");