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Diffstat (limited to 'Documentation/serial/serial-iso7816.txt')
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diff --git a/Documentation/serial/serial-iso7816.txt b/Documentation/serial/serial-iso7816.txt deleted file mode 100644 index 3193d24a2b0f..000000000000 --- a/Documentation/serial/serial-iso7816.txt +++ /dev/null @@ -1,83 +0,0 @@ - ISO7816 SERIAL COMMUNICATIONS - -1. INTRODUCTION - - ISO/IEC7816 is a series of standards specifying integrated circuit cards (ICC) - also known as smart cards. - -2. HARDWARE-RELATED CONSIDERATIONS - - Some CPUs/UARTs (e.g., Microchip AT91) contain a built-in mode capable of - handling communication with a smart card. - - For these microcontrollers, the Linux driver should be made capable of - working in both modes, and proper ioctls (see later) should be made - available at user-level to allow switching from one mode to the other, and - vice versa. - -3. DATA STRUCTURES ALREADY AVAILABLE IN THE KERNEL - - The Linux kernel provides the serial_iso7816 structure (see [1]) to handle - ISO7816 communications. This data structure is used to set and configure - ISO7816 parameters in ioctls. - - Any driver for devices capable of working both as RS232 and ISO7816 should - implement the iso7816_config callback in the uart_port structure. The - serial_core calls iso7816_config to do the device specific part in response - to TIOCGISO7816 and TIOCSISO7816 ioctls (see below). The iso7816_config - callback receives a pointer to struct serial_iso7816. - -4. USAGE FROM USER-LEVEL - - From user-level, ISO7816 configuration can be get/set using the previous - ioctls. For instance, to set ISO7816 you can use the following code: - - #include <linux/serial.h> - - /* Include definition for ISO7816 ioctls: TIOCSISO7816 and TIOCGISO7816 */ - #include <sys/ioctl.h> - - /* Open your specific device (e.g., /dev/mydevice): */ - int fd = open ("/dev/mydevice", O_RDWR); - if (fd < 0) { - /* Error handling. See errno. */ - } - - struct serial_iso7816 iso7816conf; - - /* Reserved fields as to be zeroed */ - memset(&iso7816conf, 0, sizeof(iso7816conf)); - - /* Enable ISO7816 mode: */ - iso7816conf.flags |= SER_ISO7816_ENABLED; - - /* Select the protocol: */ - /* T=0 */ - iso7816conf.flags |= SER_ISO7816_T(0); - /* or T=1 */ - iso7816conf.flags |= SER_ISO7816_T(1); - - /* Set the guard time: */ - iso7816conf.tg = 2; - - /* Set the clock frequency*/ - iso7816conf.clk = 3571200; - - /* Set transmission factors: */ - iso7816conf.sc_fi = 372; - iso7816conf.sc_di = 1; - - if (ioctl(fd_usart, TIOCSISO7816, &iso7816conf) < 0) { - /* Error handling. See errno. */ - } - - /* Use read() and write() syscalls here... */ - - /* Close the device when finished: */ - if (close (fd) < 0) { - /* Error handling. See errno. */ - } - -5. REFERENCES - - [1] include/uapi/linux/serial.h |