€•oœ      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ&/translations/zh_CN/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/zh_TW/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/it_IT/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/ja_JP/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/ko_KR/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/sp_SP/usb/gadget_printer”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒLinux USB Printer Gadget Driver”h]”hŒLinux USB Printer Gadget Driver”…””}”(hh¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh£hžhhŸŒ@/var/lib/git/docbuild/linux/Documentation/usb/gadget_printer.rst”h KubhŒ	paragraph”“”)”}”(hŒ
06/04/2007”h]”hŒ
06/04/2007”…””}”(hh¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒ4Copyright (C) 2007 Craig W. Nadler <craig@nadler.us>”h]”(hŒ$Copyright (C) 2007 Craig W. Nadler <”…””}”(hhÇhžhhŸNh NubhŒ	reference”“”)”}”(hŒcraig@nadler.us”h]”hŒcraig@nadler.us”…””}”(hhÑhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”Œmailto:craig@nadler.us”uh1hÏhhÇubhŒ>”…””}”(hhÇhžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¢)”}”(hhh]”(h§)”}”(hŒGeneral”h]”hŒGeneral”…””}”(hhîhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hhëhžhhŸh¶h Kubh¸)”}”(hŒ«This driver may be used if you are writing printer firmware using Linux as
the embedded OS. This driver has nothing to do with using a printer with
your Linux host system.”h]”hŒ«This driver may be used if you are writing printer firmware using Linux as
the embedded OS. This driver has nothing to do with using a printer with
your Linux host system.”…””}”(hhühžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khhëhžhubh¸)”}”(hXD  You will need a USB device controller and a Linux driver for it that accepts
a gadget / "device class" driver using the Linux USB Gadget API. After the
USB device controller driver is loaded then load the printer gadget driver.
This will present a printer interface to the USB Host that your USB Device
port is connected to.”h]”hXH  You will need a USB device controller and a Linux driver for it that accepts
a gadget / â€œdevice classâ€ driver using the Linux USB Gadget API. After the
USB device controller driver is loaded then load the printer gadget driver.
This will present a printer interface to the USB Host that your USB Device
port is connected to.”…””}”(hj
  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khhëhžhubh¸)”}”(hXÌ  This driver is structured for printer firmware that runs in user mode. The
user mode printer firmware will read and write data from the kernel mode
printer gadget driver using a device file. The printer returns a printer status
byte when the USB HOST sends a device request to get the printer status.  The
user space firmware can read or write this status byte using a device file
/dev/g_printer . Both blocking and non-blocking read/write calls are supported.”h]”hXÌ  This driver is structured for printer firmware that runs in user mode. The
user mode printer firmware will read and write data from the kernel mode
printer gadget driver using a device file. The printer returns a printer status
byte when the USB HOST sends a device request to get the printer status.  The
user space firmware can read or write this status byte using a device file
/dev/g_printer . Both blocking and non-blocking read/write calls are supported.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khhëhžhubeh}”(h]”Œgeneral”ah ]”h"]”Œgeneral”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kubh¢)”}”(hhh]”(h§)”}”(hŒHowto Use This Driver”h]”hŒHowto Use This Driver”…””}”(hj1  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj.  hžhhŸh¶h K#ubh¸)”}”(hŒ’To load the USB device controller driver and the printer gadget driver. The
following example uses the Netchip 2280 USB device controller driver::”h]”hŒ‘To load the USB device controller driver and the printer gadget driver. The
following example uses the Netchip 2280 USB device controller driver:”…””}”(hj?  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K%hj.  hžhubhŒliteral_block”“”)”}”(hŒ#modprobe net2280
modprobe g_printer”h]”hŒ#modprobe net2280
modprobe g_printer”…””}”hjO  sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1jM  hŸh¶h K(hj.  hžhubh¸)”}”(hŒ‰The follow command line parameter can be used when loading the printer gadget
(ex: modprobe g_printer idVendor=0x0525 idProduct=0xa4a8 ):”h]”hŒ‰The follow command line parameter can be used when loading the printer gadget
(ex: modprobe g_printer idVendor=0x0525 idProduct=0xa4a8 ):”…””}”(hj_  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K,hj.  hžhubhŒdefinition_list”“”)”}”(hhh]”(hŒdefinition_list_item”“”)”}”(hX'  idVendor
This is the Vendor ID used in the device descriptor. The default is
the Netchip vendor id 0x0525. YOU MUST CHANGE TO YOUR OWN VENDOR ID
BEFORE RELEASING A PRODUCT. If you plan to release a product and don't
already have a Vendor ID please see www.usb.org for details on how to
get one.
”h]”(hŒterm”“”)”}”(hŒidVendor”h]”hŒidVendor”…””}”(hjz  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h K4hjt  ubhŒ
definition”“”)”}”(hhh]”h¸)”}”(hX  This is the Vendor ID used in the device descriptor. The default is
the Netchip vendor id 0x0525. YOU MUST CHANGE TO YOUR OWN VENDOR ID
BEFORE RELEASING A PRODUCT. If you plan to release a product and don't
already have a Vendor ID please see www.usb.org for details on how to
get one.”h]”hX  This is the Vendor ID used in the device descriptor. The default is
the Netchip vendor id 0x0525. YOU MUST CHANGE TO YOUR OWN VENDOR ID
BEFORE RELEASING A PRODUCT. If you plan to release a product and donâ€™t
already have a Vendor ID please see www.usb.org for details on how to
get one.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K0hjŠ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hjt  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h K4hjo  ubjs  )”}”(hX  idProduct
This is the Product ID used in the device descriptor. The default
is 0xa4a8, you should change this to an ID that's not used by any of
your other USB products if you have any. It would be a good idea to
start numbering your products starting with say 0x0001.
”h]”(jy  )”}”(hŒ	idProduct”h]”hŒ	idProduct”…””}”(hj«  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h K:hj§  ubj‰  )”}”(hhh]”h¸)”}”(hX  This is the Product ID used in the device descriptor. The default
is 0xa4a8, you should change this to an ID that's not used by any of
your other USB products if you have any. It would be a good idea to
start numbering your products starting with say 0x0001.”h]”hX  This is the Product ID used in the device descriptor. The default
is 0xa4a8, you should change this to an ID thatâ€™s not used by any of
your other USB products if you have any. It would be a good idea to
start numbering your products starting with say 0x0001.”…””}”(hj¼  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K7hj¹  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hj§  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h K:hjo  hžhubjs  )”}”(hŒqbcdDevice
This is the version number of your product. It would be a good idea
to put your firmware version here.
”h]”(jy  )”}”(hŒ	bcdDevice”h]”hŒ	bcdDevice”…””}”(hjÚ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h K>hjÖ  ubj‰  )”}”(hhh]”h¸)”}”(hŒfThis is the version number of your product. It would be a good idea
to put your firmware version here.”h]”hŒfThis is the version number of your product. It would be a good idea
to put your firmware version here.”…””}”(hjë  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K=hjè  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hjÖ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h K>hjo  hžhubjs  )”}”(hŒ:iManufacturer
A string containing the name of the Vendor.
”h]”(jy  )”}”(hŒiManufacturer”h]”hŒiManufacturer”…””}”(hj	  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h KAhj  ubj‰  )”}”(hhh]”h¸)”}”(hŒ+A string containing the name of the Vendor.”h]”hŒ+A string containing the name of the Vendor.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KAhj  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h KAhjo  hžhubjs  )”}”(hŒ/iProduct
A string containing the Product Name.
”h]”(jy  )”}”(hŒiProduct”h]”hŒiProduct”…””}”(hj8  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h KDhj4  ubj‰  )”}”(hhh]”h¸)”}”(hŒ%A string containing the Product Name.”h]”hŒ%A string containing the Product Name.”…””}”(hjI  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KDhjF  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hj4  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h KDhjo  hžhubjs  )”}”(hŒhiSerialNum
A string containing the Serial Number. This should be changed for
each unit of your product.
”h]”(jy  )”}”(hŒ
iSerialNum”h]”hŒ
iSerialNum”…””}”(hjg  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h KHhjc  ubj‰  )”}”(hhh]”h¸)”}”(hŒ\A string containing the Serial Number. This should be changed for
each unit of your product.”h]”hŒ\A string containing the Serial Number. This should be changed for
each unit of your product.”…””}”(hjx  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KGhju  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hjc  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h KHhjo  hžhubjs  )”}”(hŒ¢iPNPstring
The PNP ID string used for this printer. You will want to set
either on the command line or hard code the PNP ID string used for
your printer product.
”h]”(jy  )”}”(hŒ
iPNPstring”h]”hŒ
iPNPstring”…””}”(hj–  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h KMhj’  ubj‰  )”}”(hhh]”h¸)”}”(hŒ–The PNP ID string used for this printer. You will want to set
either on the command line or hard code the PNP ID string used for
your printer product.”h]”hŒ–The PNP ID string used for this printer. You will want to set
either on the command line or hard code the PNP ID string used for
your printer product.”…””}”(hj§  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KKhj¤  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hj’  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h KMhjo  hžhubjs  )”}”(hŒ´qlen
The number of 8k buffers to use per endpoint. The default is 10, you
should tune this for your product. You may also want to tune the
size of each buffer for your product.


”h]”(jy  )”}”(hŒqlen”h]”hŒqlen”…””}”(hjÅ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jx  hŸh¶h KUhjÁ  ubj‰  )”}”(hhh]”h¸)”}”(hŒ«The number of 8k buffers to use per endpoint. The default is 10, you
should tune this for your product. You may also want to tune the
size of each buffer for your product.”h]”hŒ«The number of 8k buffers to use per endpoint. The default is 10, you
should tune this for your product. You may also want to tune the
size of each buffer for your product.”…””}”(hjÖ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KPhjÓ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jˆ  hjÁ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jr  hŸh¶h KUhjo  hžhubeh}”(h]”h ]”h"]”h$]”h&]”uh1jm  hj.  hžhhŸh¶h Nubeh}”(h]”Œhowto-use-this-driver”ah ]”h"]”Œhowto use this driver”ah$]”h&]”uh1h¡hh£hžhhŸh¶h K#ubh¢)”}”(hhh]”(h§)”}”(hŒUsing The Example Code”h]”hŒUsing The Example Code”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjþ  hžhhŸh¶h KXubh¸)”}”(hŒ=This example code talks to stdout, instead of a print engine.”h]”hŒ=This example code talks to stdout, instead of a print engine.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KZhjþ  hžhubh¸)”}”(hŒTo compile the test code below:”h]”hŒTo compile the test code below:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K\hjþ  hžhubhŒenumerated_list”“”)”}”(hhh]”(hŒ	list_item”“”)”}”(hŒ&save it to a file called prn_example.c”h]”h¸)”}”(hj4  h]”hŒ&save it to a file called prn_example.c”…””}”(hj6  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K^hj2  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j0  hj-  hžhhŸh¶h Nubj1  )”}”(hŒUcompile the code with the follow command::

      gcc prn_example.c -o prn_example


”h]”(h¸)”}”(hŒ*compile the code with the follow command::”h]”hŒ)compile the code with the follow command:”…””}”(hjM  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K_hjI  ubjN  )”}”(hŒ gcc prn_example.c -o prn_example”h]”hŒ gcc prn_example.c -o prn_example”…””}”hj[  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h KahjI  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j0  hj-  hžhhŸh¶h Nubeh}”(h]”h ]”h"]”h$]”h&]”Œenumtype”Œarabic”Œprefix”hŒsuffix”Œ)”uh1j+  hjþ  hžhhŸh¶h K^ubh¸)”}”(hŒ.To read printer data from the host to stdout::”h]”hŒ-To read printer data from the host to stdout:”…””}”(hjz  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kehjþ  hžhubjN  )”}”(hŒ# prn_example -read_data”h]”hŒ# prn_example -read_data”…””}”hjˆ  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h Kghjþ  hžhubh¸)”}”(hŒ;To write printer data from a file (data_file) to the host::”h]”hŒ:To write printer data from a file (data_file) to the host:”…””}”(hj–  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kjhjþ  hžhubjN  )”}”(hŒ)# cat data_file | prn_example -write_data”h]”hŒ)# cat data_file | prn_example -write_data”…””}”hj¤  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h Klhjþ  hžhubh¸)”}”(hŒ:To get the current printer status for the gadget driver:::”h]”hŒ9To get the current printer status for the gadget driver::”…””}”(hj²  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kohjþ  hžhubjN  )”}”(hŒl# prn_example -get_status

Printer status is:
     Printer is NOT Selected
     Paper is Out
     Printer OK”h]”hŒl# prn_example -get_status

Printer status is:
     Printer is NOT Selected
     Paper is Out
     Printer OK”…””}”hjÀ  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h Kqhjþ  hžhubh¸)”}”(hŒ$To set printer to Selected/On-line::”h]”hŒ#To set printer to Selected/On-line:”…””}”(hjÎ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kyhjþ  hžhubjN  )”}”(hŒ# prn_example -selected”h]”hŒ# prn_example -selected”…””}”hjÜ  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h K{hjþ  hžhubh¸)”}”(hŒ)To set printer to Not Selected/Off-line::”h]”hŒ(To set printer to Not Selected/Off-line:”…””}”(hjê  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K~hjþ  hžhubjN  )”}”(hŒ# prn_example -not_selected”h]”hŒ# prn_example -not_selected”…””}”hjø  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h K€hjþ  hžhubh¸)”}”(hŒ"To set paper status to paper out::”h]”hŒ!To set paper status to paper out:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kƒhjþ  hžhubjN  )”}”(hŒ# prn_example -paper_out”h]”hŒ# prn_example -paper_out”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h K…hjþ  hžhubh¸)”}”(hŒ%To set paper status to paper loaded::”h]”hŒ$To set paper status to paper loaded:”…””}”(hj"  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kˆhjþ  hžhubjN  )”}”(hŒ# prn_example -paper_loaded”h]”hŒ# prn_example -paper_loaded”…””}”hj0  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h KŠhjþ  hžhubh¸)”}”(hŒ#To set error status to printer OK::”h]”hŒ"To set error status to printer OK:”…””}”(hj>  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjþ  hžhubjN  )”}”(hŒ# prn_example -no_error”h]”hŒ# prn_example -no_error”…””}”hjL  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h Khjþ  hžhubh¸)”}”(hŒTo set error status to ERROR::”h]”hŒTo set error status to ERROR:”…””}”(hjZ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K’hjþ  hžhubjN  )”}”(hŒ# prn_example -error”h]”hŒ# prn_example -error”…””}”hjh  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h K”hjþ  hžhubeh}”(h]”Œusing-the-example-code”ah ]”h"]”Œusing the example code”ah$]”h&]”uh1h¡hh£hžhhŸh¶h KXubh¢)”}”(hhh]”(h§)”}”(hŒExample Code”h]”hŒExample Code”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj~  hžhhŸh¶h KšubjN  )”}”(hXÁ'  #include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <linux/poll.h>
#include <sys/ioctl.h>
#include <linux/usb/g_printer.h>

#define PRINTER_FILE                  "/dev/g_printer"
#define BUF_SIZE                      512


/*
 * 'usage()' - Show program usage.
 */

static void
usage(const char *option)             /* I - Option string or NULL */
{
      if (option) {
              fprintf(stderr,"prn_example: Unknown option \"%s\"!\n",
                              option);
      }

      fputs("\n", stderr);
      fputs("Usage: prn_example -[options]\n", stderr);
      fputs("Options:\n", stderr);
      fputs("\n", stderr);
      fputs("-get_status    Get the current printer status.\n", stderr);
      fputs("-selected      Set the selected status to selected.\n", stderr);
      fputs("-not_selected  Set the selected status to NOT selected.\n",
                      stderr);
      fputs("-error         Set the error status to error.\n", stderr);
      fputs("-no_error      Set the error status to NO error.\n", stderr);
      fputs("-paper_out     Set the paper status to paper out.\n", stderr);
      fputs("-paper_loaded  Set the paper status to paper loaded.\n",
                      stderr);
      fputs("-read_data     Read printer data from driver.\n", stderr);
      fputs("-write_data    Write printer sata to driver.\n", stderr);
      fputs("-NB_read_data  (Non-Blocking) Read printer data from driver.\n",
                      stderr);
      fputs("\n\n", stderr);

      exit(1);
}


static int
read_printer_data()
{
      struct pollfd   fd[1];

      /* Open device file for printer gadget. */
      fd[0].fd = open(PRINTER_FILE, O_RDWR);
      if (fd[0].fd < 0) {
              printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
              close(fd[0].fd);
              return(-1);
      }

      fd[0].events = POLLIN | POLLRDNORM;

      while (1) {
              static char buf[BUF_SIZE];
              int bytes_read;
              int retval;

              /* Wait for up to 1 second for data. */
              retval = poll(fd, 1, 1000);

              if (retval && (fd[0].revents & POLLRDNORM)) {

                      /* Read data from printer gadget driver. */
                      bytes_read = read(fd[0].fd, buf, BUF_SIZE);

                      if (bytes_read < 0) {
                              printf("Error %d reading from %s\n",
                                              fd[0].fd, PRINTER_FILE);
                              close(fd[0].fd);
                              return(-1);
                      } else if (bytes_read > 0) {
                              /* Write data to standard OUTPUT (stdout). */
                              fwrite(buf, 1, bytes_read, stdout);
                              fflush(stdout);
                      }

              }

      }

      /* Close the device file. */
      close(fd[0].fd);

      return 0;
}


static int
write_printer_data()
{
      struct pollfd   fd[1];

      /* Open device file for printer gadget. */
      fd[0].fd = open (PRINTER_FILE, O_RDWR);
      if (fd[0].fd < 0) {
              printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
              close(fd[0].fd);
              return(-1);
      }

      fd[0].events = POLLOUT | POLLWRNORM;

      while (1) {
              int retval;
              static char buf[BUF_SIZE];
              /* Read data from standard INPUT (stdin). */
              int bytes_read = fread(buf, 1, BUF_SIZE, stdin);

              if (!bytes_read) {
                      break;
              }

              while (bytes_read) {

                      /* Wait for up to 1 second to sent data. */
                      retval = poll(fd, 1, 1000);

                      /* Write data to printer gadget driver. */
                      if (retval && (fd[0].revents & POLLWRNORM)) {
                              retval = write(fd[0].fd, buf, bytes_read);
                              if (retval < 0) {
                                      printf("Error %d writing to %s\n",
                                                      fd[0].fd,
                                                      PRINTER_FILE);
                                      close(fd[0].fd);
                                      return(-1);
                              } else {
                                      bytes_read -= retval;
                              }

                      }

              }

      }

      /* Wait until the data has been sent. */
      fsync(fd[0].fd);

      /* Close the device file. */
      close(fd[0].fd);

      return 0;
}


static int
read_NB_printer_data()
{
      int             fd;
      static char     buf[BUF_SIZE];
      int             bytes_read;

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR|O_NONBLOCK);
      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      while (1) {
              /* Read data from printer gadget driver. */
              bytes_read = read(fd, buf, BUF_SIZE);
              if (bytes_read <= 0) {
                      break;
              }

              /* Write data to standard OUTPUT (stdout). */
              fwrite(buf, 1, bytes_read, stdout);
              fflush(stdout);
      }

      /* Close the device file. */
      close(fd);

      return 0;
}


static int
get_printer_status()
{
      int     retval;
      int     fd;

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR);
      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      /* Make the IOCTL call. */
      retval = ioctl(fd, GADGET_GET_PRINTER_STATUS);
      if (retval < 0) {
              fprintf(stderr, "ERROR: Failed to set printer status\n");
              return(-1);
      }

      /* Close the device file. */
      close(fd);

      return(retval);
}


static int
set_printer_status(unsigned char buf, int clear_printer_status_bit)
{
      int     retval;
      int     fd;

      retval = get_printer_status();
      if (retval < 0) {
              fprintf(stderr, "ERROR: Failed to get printer status\n");
              return(-1);
      }

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR);

      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      if (clear_printer_status_bit) {
              retval &= ~buf;
      } else {
              retval |= buf;
      }

      /* Make the IOCTL call. */
      if (ioctl(fd, GADGET_SET_PRINTER_STATUS, (unsigned char)retval)) {
              fprintf(stderr, "ERROR: Failed to set printer status\n");
              return(-1);
      }

      /* Close the device file. */
      close(fd);

      return 0;
}


static int
display_printer_status()
{
      char    printer_status;

      printer_status = get_printer_status();
      if (printer_status < 0) {
              fprintf(stderr, "ERROR: Failed to get printer status\n");
              return(-1);
      }

      printf("Printer status is:\n");
      if (printer_status & PRINTER_SELECTED) {
              printf("     Printer is Selected\n");
      } else {
              printf("     Printer is NOT Selected\n");
      }
      if (printer_status & PRINTER_PAPER_EMPTY) {
              printf("     Paper is Out\n");
      } else {
              printf("     Paper is Loaded\n");
      }
      if (printer_status & PRINTER_NOT_ERROR) {
              printf("     Printer OK\n");
      } else {
              printf("     Printer ERROR\n");
      }

      return(0);
}


int
main(int  argc, char *argv[])
{
      int     i;              /* Looping var */
      int     retval = 0;

      /* No Args */
      if (argc == 1) {
              usage(0);
              exit(0);
      }

      for (i = 1; i < argc && !retval; i ++) {

              if (argv[i][0] != '-') {
                      continue;
              }

              if (!strcmp(argv[i], "-get_status")) {
                      if (display_printer_status()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-paper_loaded")) {
                      if (set_printer_status(PRINTER_PAPER_EMPTY, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-paper_out")) {
                      if (set_printer_status(PRINTER_PAPER_EMPTY, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-selected")) {
                      if (set_printer_status(PRINTER_SELECTED, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-not_selected")) {
                      if (set_printer_status(PRINTER_SELECTED, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-error")) {
                      if (set_printer_status(PRINTER_NOT_ERROR, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-no_error")) {
                      if (set_printer_status(PRINTER_NOT_ERROR, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-read_data")) {
                      if (read_printer_data()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-write_data")) {
                      if (write_printer_data()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-NB_read_data")) {
                      if (read_NB_printer_data()) {
                              retval = 1;
                      }

              } else {
                      usage(argv[i]);
                      retval = 1;
              }
      }

      exit(retval);
}”h]”hXÁ'  #include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <linux/poll.h>
#include <sys/ioctl.h>
#include <linux/usb/g_printer.h>

#define PRINTER_FILE                  "/dev/g_printer"
#define BUF_SIZE                      512


/*
 * 'usage()' - Show program usage.
 */

static void
usage(const char *option)             /* I - Option string or NULL */
{
      if (option) {
              fprintf(stderr,"prn_example: Unknown option \"%s\"!\n",
                              option);
      }

      fputs("\n", stderr);
      fputs("Usage: prn_example -[options]\n", stderr);
      fputs("Options:\n", stderr);
      fputs("\n", stderr);
      fputs("-get_status    Get the current printer status.\n", stderr);
      fputs("-selected      Set the selected status to selected.\n", stderr);
      fputs("-not_selected  Set the selected status to NOT selected.\n",
                      stderr);
      fputs("-error         Set the error status to error.\n", stderr);
      fputs("-no_error      Set the error status to NO error.\n", stderr);
      fputs("-paper_out     Set the paper status to paper out.\n", stderr);
      fputs("-paper_loaded  Set the paper status to paper loaded.\n",
                      stderr);
      fputs("-read_data     Read printer data from driver.\n", stderr);
      fputs("-write_data    Write printer sata to driver.\n", stderr);
      fputs("-NB_read_data  (Non-Blocking) Read printer data from driver.\n",
                      stderr);
      fputs("\n\n", stderr);

      exit(1);
}


static int
read_printer_data()
{
      struct pollfd   fd[1];

      /* Open device file for printer gadget. */
      fd[0].fd = open(PRINTER_FILE, O_RDWR);
      if (fd[0].fd < 0) {
              printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
              close(fd[0].fd);
              return(-1);
      }

      fd[0].events = POLLIN | POLLRDNORM;

      while (1) {
              static char buf[BUF_SIZE];
              int bytes_read;
              int retval;

              /* Wait for up to 1 second for data. */
              retval = poll(fd, 1, 1000);

              if (retval && (fd[0].revents & POLLRDNORM)) {

                      /* Read data from printer gadget driver. */
                      bytes_read = read(fd[0].fd, buf, BUF_SIZE);

                      if (bytes_read < 0) {
                              printf("Error %d reading from %s\n",
                                              fd[0].fd, PRINTER_FILE);
                              close(fd[0].fd);
                              return(-1);
                      } else if (bytes_read > 0) {
                              /* Write data to standard OUTPUT (stdout). */
                              fwrite(buf, 1, bytes_read, stdout);
                              fflush(stdout);
                      }

              }

      }

      /* Close the device file. */
      close(fd[0].fd);

      return 0;
}


static int
write_printer_data()
{
      struct pollfd   fd[1];

      /* Open device file for printer gadget. */
      fd[0].fd = open (PRINTER_FILE, O_RDWR);
      if (fd[0].fd < 0) {
              printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
              close(fd[0].fd);
              return(-1);
      }

      fd[0].events = POLLOUT | POLLWRNORM;

      while (1) {
              int retval;
              static char buf[BUF_SIZE];
              /* Read data from standard INPUT (stdin). */
              int bytes_read = fread(buf, 1, BUF_SIZE, stdin);

              if (!bytes_read) {
                      break;
              }

              while (bytes_read) {

                      /* Wait for up to 1 second to sent data. */
                      retval = poll(fd, 1, 1000);

                      /* Write data to printer gadget driver. */
                      if (retval && (fd[0].revents & POLLWRNORM)) {
                              retval = write(fd[0].fd, buf, bytes_read);
                              if (retval < 0) {
                                      printf("Error %d writing to %s\n",
                                                      fd[0].fd,
                                                      PRINTER_FILE);
                                      close(fd[0].fd);
                                      return(-1);
                              } else {
                                      bytes_read -= retval;
                              }

                      }

              }

      }

      /* Wait until the data has been sent. */
      fsync(fd[0].fd);

      /* Close the device file. */
      close(fd[0].fd);

      return 0;
}


static int
read_NB_printer_data()
{
      int             fd;
      static char     buf[BUF_SIZE];
      int             bytes_read;

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR|O_NONBLOCK);
      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      while (1) {
              /* Read data from printer gadget driver. */
              bytes_read = read(fd, buf, BUF_SIZE);
              if (bytes_read <= 0) {
                      break;
              }

              /* Write data to standard OUTPUT (stdout). */
              fwrite(buf, 1, bytes_read, stdout);
              fflush(stdout);
      }

      /* Close the device file. */
      close(fd);

      return 0;
}


static int
get_printer_status()
{
      int     retval;
      int     fd;

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR);
      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      /* Make the IOCTL call. */
      retval = ioctl(fd, GADGET_GET_PRINTER_STATUS);
      if (retval < 0) {
              fprintf(stderr, "ERROR: Failed to set printer status\n");
              return(-1);
      }

      /* Close the device file. */
      close(fd);

      return(retval);
}


static int
set_printer_status(unsigned char buf, int clear_printer_status_bit)
{
      int     retval;
      int     fd;

      retval = get_printer_status();
      if (retval < 0) {
              fprintf(stderr, "ERROR: Failed to get printer status\n");
              return(-1);
      }

      /* Open device file for printer gadget. */
      fd = open(PRINTER_FILE, O_RDWR);

      if (fd < 0) {
              printf("Error %d opening %s\n", fd, PRINTER_FILE);
              close(fd);
              return(-1);
      }

      if (clear_printer_status_bit) {
              retval &= ~buf;
      } else {
              retval |= buf;
      }

      /* Make the IOCTL call. */
      if (ioctl(fd, GADGET_SET_PRINTER_STATUS, (unsigned char)retval)) {
              fprintf(stderr, "ERROR: Failed to set printer status\n");
              return(-1);
      }

      /* Close the device file. */
      close(fd);

      return 0;
}


static int
display_printer_status()
{
      char    printer_status;

      printer_status = get_printer_status();
      if (printer_status < 0) {
              fprintf(stderr, "ERROR: Failed to get printer status\n");
              return(-1);
      }

      printf("Printer status is:\n");
      if (printer_status & PRINTER_SELECTED) {
              printf("     Printer is Selected\n");
      } else {
              printf("     Printer is NOT Selected\n");
      }
      if (printer_status & PRINTER_PAPER_EMPTY) {
              printf("     Paper is Out\n");
      } else {
              printf("     Paper is Loaded\n");
      }
      if (printer_status & PRINTER_NOT_ERROR) {
              printf("     Printer OK\n");
      } else {
              printf("     Printer ERROR\n");
      }

      return(0);
}


int
main(int  argc, char *argv[])
{
      int     i;              /* Looping var */
      int     retval = 0;

      /* No Args */
      if (argc == 1) {
              usage(0);
              exit(0);
      }

      for (i = 1; i < argc && !retval; i ++) {

              if (argv[i][0] != '-') {
                      continue;
              }

              if (!strcmp(argv[i], "-get_status")) {
                      if (display_printer_status()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-paper_loaded")) {
                      if (set_printer_status(PRINTER_PAPER_EMPTY, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-paper_out")) {
                      if (set_printer_status(PRINTER_PAPER_EMPTY, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-selected")) {
                      if (set_printer_status(PRINTER_SELECTED, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-not_selected")) {
                      if (set_printer_status(PRINTER_SELECTED, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-error")) {
                      if (set_printer_status(PRINTER_NOT_ERROR, 1)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-no_error")) {
                      if (set_printer_status(PRINTER_NOT_ERROR, 0)) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-read_data")) {
                      if (read_printer_data()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-write_data")) {
                      if (write_printer_data()) {
                              retval = 1;
                      }

              } else if (!strcmp(argv[i], "-NB_read_data")) {
                      if (read_NB_printer_data()) {
                              retval = 1;
                      }

              } else {
                      usage(argv[i]);
                      retval = 1;
              }
      }

      exit(retval);
}”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j]  j^  uh1jM  hŸh¶h KŸhj~  hžhubeh}”(h]”Œexample-code”ah ]”h"]”Œexample code”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kšubeh}”(h]”Œlinux-usb-printer-gadget-driver”ah ]”h"]”Œlinux usb printer gadget driver”ah$]”h&]”uh1h¡hhhžhhŸh¶h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h¶uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¦NŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
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