diff options
Diffstat (limited to 'Documentation/serial')
| -rw-r--r-- | Documentation/serial/00-INDEX | 16 | ||||
| -rw-r--r-- | Documentation/serial/driver | 2 | ||||
| -rw-r--r-- | Documentation/serial/serial-iso7816.txt | 83 |
3 files changed, 84 insertions, 17 deletions
diff --git a/Documentation/serial/00-INDEX b/Documentation/serial/00-INDEX deleted file mode 100644 index 8021a9f29fc5..000000000000 --- a/Documentation/serial/00-INDEX +++ /dev/null @@ -1,16 +0,0 @@ -00-INDEX - - this file. -README.cycladesZ - - info on Cyclades-Z firmware loading. -driver - - intro to the low level serial driver. -moxa-smartio - - file with info on installing/using Moxa multiport serial driver. -n_gsm.txt - - GSM 0710 tty multiplexer howto. -rocket.txt - - info on the Comtrol RocketPort multiport serial driver. -serial-rs485.txt - - info about RS485 structures and support in the kernel. -tty.txt - - guide to the locking policies of the tty layer. diff --git a/Documentation/serial/driver b/Documentation/serial/driver index da193e092fc3..86e47c19a924 100644 --- a/Documentation/serial/driver +++ b/Documentation/serial/driver @@ -7,7 +7,7 @@ This document is meant as a brief overview of some aspects of the new serial driver. It is not complete, any questions you have should be directed to <rmk@arm.linux.org.uk> -The reference implementation is contained within amba_pl011.c. +The reference implementation is contained within amba-pl011.c. diff --git a/Documentation/serial/serial-iso7816.txt b/Documentation/serial/serial-iso7816.txt new file mode 100644 index 000000000000..3193d24a2b0f --- /dev/null +++ b/Documentation/serial/serial-iso7816.txt @@ -0,0 +1,83 @@ + 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 |