From: Nicolas Ferre Date: Wed, 26 Sep 2018 12:58:47 +0000 (+0200) Subject: tty/serial_core: add ISO7816 infrastructure X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ad8c0eaa0a418ae8ef3f9217638bb86439399eac;p=openwrt%2Fstaging%2Fblogic.git tty/serial_core: add ISO7816 infrastructure Add the ISO7816 ioctl and associated accessors and data structure. Drivers can then use this common implementation to handle ISO7816 (smart cards). Signed-off-by: Nicolas Ferre [ludovic.desroches@microchip.com: squash and rebase, removal of gpios, checkpatch fixes] Signed-off-by: Ludovic Desroches Signed-off-by: Greg Kroah-Hartman --- 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 + + /* Include definition for ISO7816 ioctls: TIOCSISO7816 and TIOCGISO7816 */ + #include + + /* 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 diff --git a/arch/alpha/include/uapi/asm/ioctls.h b/arch/alpha/include/uapi/asm/ioctls.h index 3729d92d3fa8..1e9121c9b3c7 100644 --- a/arch/alpha/include/uapi/asm/ioctls.h +++ b/arch/alpha/include/uapi/asm/ioctls.h @@ -102,6 +102,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define TIOCSERCONFIG 0x5453 #define TIOCSERGWILD 0x5454 diff --git a/arch/mips/include/uapi/asm/ioctls.h b/arch/mips/include/uapi/asm/ioctls.h index 890245a9f0c4..16aa8a766aec 100644 --- a/arch/mips/include/uapi/asm/ioctls.h +++ b/arch/mips/include/uapi/asm/ioctls.h @@ -93,6 +93,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) /* I hope the range from 0x5480 on is free ... */ #define TIOCSCTTY 0x5480 /* become controlling tty */ diff --git a/arch/parisc/include/uapi/asm/ioctls.h b/arch/parisc/include/uapi/asm/ioctls.h index aafb1c0ca0af..82d1148c6379 100644 --- a/arch/parisc/include/uapi/asm/ioctls.h +++ b/arch/parisc/include/uapi/asm/ioctls.h @@ -62,6 +62,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define FIONCLEX 0x5450 /* these numbers need to be adjusted. */ #define FIOCLEX 0x5451 diff --git a/arch/powerpc/include/uapi/asm/ioctls.h b/arch/powerpc/include/uapi/asm/ioctls.h index 41b1a5c15734..2c145da3b774 100644 --- a/arch/powerpc/include/uapi/asm/ioctls.h +++ b/arch/powerpc/include/uapi/asm/ioctls.h @@ -102,6 +102,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define TIOCSERCONFIG 0x5453 #define TIOCSERGWILD 0x5454 diff --git a/arch/sh/include/uapi/asm/ioctls.h b/arch/sh/include/uapi/asm/ioctls.h index cc62f6f98103..11866d4f60e1 100644 --- a/arch/sh/include/uapi/asm/ioctls.h +++ b/arch/sh/include/uapi/asm/ioctls.h @@ -95,6 +95,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define TIOCSERCONFIG _IO('T', 83) /* 0x5453 */ #define TIOCSERGWILD _IOR('T', 84, int) /* 0x5454 */ diff --git a/arch/sparc/include/uapi/asm/ioctls.h b/arch/sparc/include/uapi/asm/ioctls.h index 2df52711e170..7fd2f5873c9e 100644 --- a/arch/sparc/include/uapi/asm/ioctls.h +++ b/arch/sparc/include/uapi/asm/ioctls.h @@ -27,6 +27,8 @@ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGRS485 _IOR('T', 0x41, struct serial_rs485) #define TIOCSRS485 _IOWR('T', 0x42, struct serial_rs485) +#define TIOCGISO7816 _IOR('T', 0x43, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x44, struct serial_iso7816) /* Note that all the ioctls that are not available in Linux have a * double underscore on the front to: a) avoid some programs to diff --git a/arch/xtensa/include/uapi/asm/ioctls.h b/arch/xtensa/include/uapi/asm/ioctls.h index ec43609cbfc5..6d4a87296c95 100644 --- a/arch/xtensa/include/uapi/asm/ioctls.h +++ b/arch/xtensa/include/uapi/asm/ioctls.h @@ -107,6 +107,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define TIOCSERCONFIG _IO('T', 83) #define TIOCSERGWILD _IOR('T', 84, int) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index ed0133395cc7..0a4e6eeb5ff3 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1308,6 +1308,58 @@ static int uart_set_rs485_config(struct uart_port *port, return 0; } +static int uart_get_iso7816_config(struct uart_port *port, + struct serial_iso7816 __user *iso7816) +{ + unsigned long flags; + struct serial_iso7816 aux; + + if (!port->iso7816_config) + return -ENOIOCTLCMD; + + spin_lock_irqsave(&port->lock, flags); + aux = port->iso7816; + spin_unlock_irqrestore(&port->lock, flags); + + if (copy_to_user(iso7816, &aux, sizeof(aux))) + return -EFAULT; + + return 0; +} + +static int uart_set_iso7816_config(struct uart_port *port, + struct serial_iso7816 __user *iso7816_user) +{ + struct serial_iso7816 iso7816; + int i, ret; + unsigned long flags; + + if (!port->iso7816_config) + return -ENOIOCTLCMD; + + if (copy_from_user(&iso7816, iso7816_user, sizeof(*iso7816_user))) + return -EFAULT; + + /* + * There are 5 words reserved for future use. Check that userspace + * doesn't put stuff in there to prevent breakages in the future. + */ + for (i = 0; i < 5; i++) + if (iso7816.reserved[i]) + return -EINVAL; + + spin_lock_irqsave(&port->lock, flags); + ret = port->iso7816_config(port, &iso7816); + spin_unlock_irqrestore(&port->lock, flags); + if (ret) + return ret; + + if (copy_to_user(iso7816_user, &port->iso7816, sizeof(port->iso7816))) + return -EFAULT; + + return 0; +} + /* * Called via sys_ioctl. We can use spin_lock_irq() here. */ @@ -1392,6 +1444,14 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) case TIOCSRS485: ret = uart_set_rs485_config(uport, uarg); break; + + case TIOCSISO7816: + ret = uart_set_iso7816_config(state->uart_port, uarg); + break; + + case TIOCGISO7816: + ret = uart_get_iso7816_config(state->uart_port, uarg); + break; default: if (uport->ops->ioctl) ret = uport->ops->ioctl(uport, cmd, arg); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 079793e5d3fa..4e2ba4894dcc 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -144,6 +144,8 @@ struct uart_port { void (*handle_break)(struct uart_port *); int (*rs485_config)(struct uart_port *, struct serial_rs485 *rs485); + int (*iso7816_config)(struct uart_port *, + struct serial_iso7816 *iso7816); unsigned int irq; /* irq number */ unsigned long irqflags; /* irq flags */ unsigned int uartclk; /* base uart clock */ @@ -261,6 +263,7 @@ struct uart_port { struct attribute_group *attr_group; /* port specific attributes */ const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ struct serial_rs485 rs485; + struct serial_iso7816 iso7816; void *private_data; /* generic platform data pointer */ }; diff --git a/include/uapi/asm-generic/ioctls.h b/include/uapi/asm-generic/ioctls.h index 040651735662..cdc9f4ca8c27 100644 --- a/include/uapi/asm-generic/ioctls.h +++ b/include/uapi/asm-generic/ioctls.h @@ -79,6 +79,8 @@ #define TIOCGPTLCK _IOR('T', 0x39, int) /* Get Pty lock state */ #define TIOCGEXCL _IOR('T', 0x40, int) /* Get exclusive mode state */ #define TIOCGPTPEER _IO('T', 0x41) /* Safely open the slave */ +#define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816) +#define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816) #define FIONCLEX 0x5450 #define FIOCLEX 0x5451 diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h index 3fdd0dee8b41..93eb3c496ff1 100644 --- a/include/uapi/linux/serial.h +++ b/include/uapi/linux/serial.h @@ -132,4 +132,21 @@ struct serial_rs485 { are a royal PITA .. */ }; +/* + * Serial interface for controlling ISO7816 settings on chips with suitable + * support. Set with TIOCSISO7816 and get with TIOCGISO7816 if supported by + * your platform. + */ +struct serial_iso7816 { + __u32 flags; /* ISO7816 feature flags */ +#define SER_ISO7816_ENABLED (1 << 0) +#define SER_ISO7816_T_PARAM (0x0f << 4) +#define SER_ISO7816_T(t) (((t) & 0x0f) << 4) + __u32 tg; + __u32 sc_fi; + __u32 sc_di; + __u32 clk; + __u32 reserved[5]; +}; + #endif /* _UAPI_LINUX_SERIAL_H */