/* * Copyright (C) 2009 by Bart Hartgers (bart.hartgers+ark3116@gmail.com) * Original version: * Copyright (C) 2006 * Simon Schulz (ark3116_driver auctionant.de) * * ark3116 * - implements a driver for the arkmicro ark3116 chipset (vendor=0x6547, * productid=0x0232) (used in a datacable called KQ-U8A) * * Supports full modem status lines, break, hardware flow control. Does not * support software flow control, since I do not know how to enable it in hw. * * This driver is a essentially new implementation. I initially dug * into the old ark3116.c driver and suddenly realized the ark3116 is * a 16450 with a USB interface glued to it. See comments at the * bottom of this file. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRIVER_AUTHOR "Bart Hartgers " #define DRIVER_DESC "USB ARK3116 serial/IrDA driver" #define DRIVER_DEV_DESC "ARK3116 RS232/IrDA" #define DRIVER_NAME "ark3116" /* usb timeout of 1 second */ #define ARK_TIMEOUT (1*HZ) static const struct usb_device_id id_table[] = { { USB_DEVICE(0x6547, 0x0232) }, { USB_DEVICE(0x18ec, 0x3118) }, /* USB to IrDA adapter */ { }, }; MODULE_DEVICE_TABLE(usb, id_table); static int is_irda(struct usb_serial *serial) { struct usb_device *dev = serial->dev; if (le16_to_cpu(dev->descriptor.idVendor) == 0x18ec && le16_to_cpu(dev->descriptor.idProduct) == 0x3118) return 1; return 0; } struct ark3116_private { int irda; /* 1 for irda device */ /* protects hw register updates */ struct mutex hw_lock; int quot; /* baudrate divisor */ __u32 lcr; /* line control register value */ __u32 hcr; /* handshake control register (0x8) * value */ __u32 mcr; /* modem contol register value */ /* protects the status values below */ spinlock_t status_lock; __u32 msr; /* modem status register value */ __u32 lsr; /* line status register value */ }; static int ark3116_write_reg(struct usb_serial *serial, unsigned reg, __u8 val) { int result; /* 0xfe 0x40 are magic values taken from original driver */ result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), 0xfe, 0x40, val, reg, NULL, 0, ARK_TIMEOUT); return result; } static int ark3116_read_reg(struct usb_serial *serial, unsigned reg, unsigned char *buf) { int result; /* 0xfe 0xc0 are magic values taken from original driver */ result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0), 0xfe, 0xc0, 0, reg, buf, 1, ARK_TIMEOUT); if (result < 0) return result; else return buf[0]; } static inline int calc_divisor(int bps) { /* Original ark3116 made some exceptions in rounding here * because windows did the same. Assume that is not really * necessary. * Crystal is 12MHz, probably because of USB, but we divide by 4? */ return (12000000 + 2*bps) / (4*bps); } static int ark3116_attach(struct usb_serial *serial) { /* make sure we have our end-points */ if ((serial->num_bulk_in == 0) || (serial->num_bulk_out == 0) || (serial->num_interrupt_in == 0)) { dev_err(&serial->dev->dev, "%s - missing endpoint - " "bulk in: %d, bulk out: %d, int in %d\n", KBUILD_MODNAME, serial->num_bulk_in, serial->num_bulk_out, serial->num_interrupt_in); return -EINVAL; } return 0; } static int ark3116_port_probe(struct usb_serial_port *port) { struct usb_serial *serial = port->serial; struct ark3116_private *priv; priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; mutex_init(&priv->hw_lock); spin_lock_init(&priv->status_lock); priv->irda = is_irda(serial); usb_set_serial_port_data(port, priv); /* setup the hardware */ ark3116_write_reg(serial, UART_IER, 0); /* disable DMA */ ark3116_write_reg(serial, UART_FCR, 0); /* handshake control */ priv->hcr = 0; ark3116_write_reg(serial, 0x8 , 0); /* modem control */ priv->mcr = 0; ark3116_write_reg(serial, UART_MCR, 0); if (!(priv->irda)) { ark3116_write_reg(serial, 0xb , 0); } else { ark3116_write_reg(serial, 0xb , 1); ark3116_write_reg(serial, 0xc , 0); ark3116_write_reg(serial, 0xd , 0x41); ark3116_write_reg(serial, 0xa , 1); } /* setup baudrate */ ark3116_write_reg(serial, UART_LCR, UART_LCR_DLAB); /* setup for 9600 8N1 */ priv->quot = calc_divisor(9600); ark3116_write_reg(serial, UART_DLL, priv->quot & 0xff); ark3116_write_reg(serial, UART_DLM, (priv->quot>>8) & 0xff); priv->lcr = UART_LCR_WLEN8; ark3116_write_reg(serial, UART_LCR, UART_LCR_WLEN8); ark3116_write_reg(serial, 0xe, 0); if (priv->irda) ark3116_write_reg(serial, 0x9, 0); dev_info(&serial->dev->dev, "%s using %s mode\n", KBUILD_MODNAME, priv->irda ? "IrDA" : "RS232"); return 0; } static int ark3116_port_remove(struct usb_serial_port *port) { struct ark3116_private *priv = usb_get_serial_port_data(port); /* device is closed, so URBs and DMA should be down */ mutex_destroy(&priv->hw_lock); kfree(priv); return 0; } static void ark3116_init_termios(struct tty_struct *tty) { struct ktermios *termios = &tty->termios; *termios = tty_std_termios; termios->c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; termios->c_ispeed = 9600; termios->c_ospeed = 9600; } static void ark3116_set_termios(struct tty_struct *tty, struct usb_serial_port *port, struct ktermios *old_termios) { struct usb_serial *serial = port->serial; struct ark3116_private *priv = usb_get_serial_port_data(port); struct ktermios *termios = &tty->termios; unsigned int cflag = termios->c_cflag; int bps = tty_get_baud_rate(tty); int quot; __u8 lcr, hcr, eval; /* set data bit count */ switch (cflag & CSIZE) { case CS5: lcr = UART_LCR_WLEN5; break; case CS6: lcr = UART_LCR_WLEN6; break; case CS7: lcr = UART_LCR_WLEN7; break; default: case CS8: lcr = UART_LCR_WLEN8; break; } if (cflag & CSTOPB) lcr |= UART_LCR_STOP; if (cflag & PARENB) lcr |= UART_LCR_PARITY; if (!(cflag & PARODD)) lcr |= UART_LCR_EPAR; #ifdef CMSPAR if (cflag & CMSPAR) lcr |= UART_LCR_SPAR; #endif /* handshake control */ hcr = (cflag & CRTSCTS) ? 0x03 : 0x00; /* calc baudrate */ dev_dbg(&port->dev, "%s - setting bps to %d\n", __func__, bps); eval = 0; switch (bps) { case 0: quot = calc_divisor(9600); break; default: if ((bps < 75) || (bps > 3000000)) bps = 9600; quot = calc_divisor(bps); break; case 460800: eval = 1; quot = calc_divisor(bps); break; case 921600: eval = 2; quot = calc_divisor(bps); break; } /* Update state: synchronize */ mutex_lock(&priv->hw_lock); /* keep old LCR_SBC bit */ lcr |= (priv->lcr & UART_LCR_SBC); dev_dbg(&port->dev, "%s - setting hcr:0x%02x,lcr:0x%02x,quot:%d\n", __func__, hcr, lcr, quot); /* handshake control */ if (priv->hcr != hcr) { priv->hcr = hcr; ark3116_write_reg(serial, 0x8, hcr); } /* baudrate */ if (priv->quot != quot) { priv->quot = quot; priv->lcr = lcr; /* need to write lcr anyway */ /* disable DMA since transmit/receive is * shadowed by UART_DLL */ ark3116_write_reg(serial, UART_FCR, 0); ark3116_write_reg(serial, UART_LCR, lcr|UART_LCR_DLAB); ark3116_write_reg(serial, UART_DLL, quot & 0xff); ark3116_write_reg(serial, UART_DLM, (quot>>8) & 0xff); /* restore lcr */ ark3116_write_reg(serial, UART_LCR, lcr); /* magic baudrate thingy: not sure what it does, * but windows does this as well. */ ark3116_write_reg(serial, 0xe, eval); /* enable DMA */ ark3116_write_reg(serial, UART_FCR, UART_FCR_DMA_SELECT); } else if (priv->lcr != lcr) { priv->lcr = lcr; ark3116_write_reg(serial, UART_LCR, lcr); } mutex_unlock(&priv->hw_lock); /* check for software flow control */ if (I_IXOFF(tty) || I_IXON(tty)) { dev_warn(&serial->dev->dev, "%s: don't know how to do software flow control\n", KBUILD_MODNAME); } /* Don't rewrite B0 */ if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, bps, bps); } static void ark3116_close(struct usb_serial_port *port) { struct usb_serial *serial = port->serial; /* disable DMA */ ark3116_write_reg(serial, UART_FCR, 0); /* deactivate interrupts */ ark3116_write_reg(serial, UART_IER, 0); usb_serial_generic_close(port); if (serial->num_interrupt_in) usb_kill_urb(port->interrupt_in_urb); } static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) { struct ark3116_private *priv = usb_get_serial_port_data(port); struct usb_serial *serial = port->serial; unsigned char *buf; int result; buf = kmalloc(1, GFP_KERNEL); if (buf == NULL) return -ENOMEM; result = usb_serial_generic_open(tty, port); if (result) { dev_dbg(&port->dev, "%s - usb_serial_generic_open failed: %d\n", __func__, result); goto err_out; } /* remove any data still left: also clears error state */ ark3116_read_reg(serial, UART_RX, buf); /* read modem status */ priv->msr = ark3116_read_reg(serial, UART_MSR, buf); /* read line status */ priv->lsr = ark3116_read_reg(serial, UART_LSR, buf); result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); if (result) { dev_err(&port->dev, "submit irq_in urb failed %d\n", result); ark3116_close(port); goto err_out; } /* activate interrupts */ ark3116_write_reg(port->serial, UART_IER, UART_IER_MSI|UART_IER_RLSI); /* enable DMA */ ark3116_write_reg(port->serial, UART_FCR, UART_FCR_DMA_SELECT); /* setup termios */ if (tty) ark3116_set_termios(tty, port, NULL); err_out: kfree(buf); return result; } static int ark3116_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { struct usb_serial_port *port = tty->driver_data; struct serial_struct serstruct; void __user *user_arg = (void __user *)arg; switch (cmd) { case TIOCGSERIAL: /* XXX: Some of these values are probably wrong. */ memset(&serstruct, 0, sizeof(serstruct)); serstruct.type = PORT_16654; serstruct.line = port->serial->minor; serstruct.port = port->number; serstruct.custom_divisor = 0; serstruct.baud_base = 460800; if (copy_to_user(user_arg, &serstruct, sizeof(serstruct))) return -EFAULT; return 0; case TIOCSSERIAL: if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) return -EFAULT; return 0; case TIOCMIWAIT: for (;;) { struct async_icount prev = port->icount; interruptible_sleep_on(&port->delta_msr_wait); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; if (port->serial->disconnected) return -EIO; if ((prev.rng == port->icount.rng) && (prev.dsr == port->icount.dsr) && (prev.dcd == port->icount.dcd) && (prev.cts == port->icount.cts)) return -EIO; if ((arg & TIOCM_RNG && (prev.rng != port->icount.rng)) || (arg & TIOCM_DSR && (prev.dsr != port->icount.dsr)) || (arg & TIOCM_CD && (prev.dcd != port->icount.dcd)) || (arg & TIOCM_CTS && (prev.cts != port->icount.cts))) return 0; } break; } return -ENOIOCTLCMD; } static int ark3116_tiocmget(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct ark3116_private *priv = usb_get_serial_port_data(port); __u32 status; __u32 ctrl; unsigned long flags; mutex_lock(&priv->hw_lock); ctrl = priv->mcr; mutex_unlock(&priv->hw_lock); spin_lock_irqsave(&priv->status_lock, flags); status = priv->msr; spin_unlock_irqrestore(&priv->status_lock, flags); return (status & UART_MSR_DSR ? TIOCM_DSR : 0) | (status & UART_MSR_CTS ? TIOCM_CTS : 0) | (status & UART_MSR_RI ? TIOCM_RI : 0) | (status & UART_MSR_DCD ? TIOCM_CD : 0) | (ctrl & UART_MCR_DTR ? TIOCM_DTR : 0) | (ctrl & UART_MCR_RTS ? TIOCM_RTS : 0) | (ctrl & UART_MCR_OUT1 ? TIOCM_OUT1 : 0) | (ctrl & UART_MCR_OUT2 ? TIOCM_OUT2 : 0); } static int ark3116_tiocmset(struct tty_struct *tty, unsigned set, unsigned clr) { struct usb_serial_port *port = tty->driver_data; struct ark3116_private *priv = usb_get_serial_port_data(port); /* we need to take the mutex here, to make sure that the value * in priv->mcr is actually the one that is in the hardware */ mutex_lock(&priv->hw_lock); if (set & TIOCM_RTS) priv->mcr |= UART_MCR_RTS; if (set & TIOCM_DTR) priv->mcr |= UART_MCR_DTR; if (set & TIOCM_OUT1) priv->mcr |= UART_MCR_OUT1; if (set & TIOCM_OUT2) priv->mcr |= UART_MCR_OUT2; if (clr & TIOCM_RTS) priv->mcr &= ~UART_MCR_RTS; if (clr & TIOCM_DTR) priv->mcr &= ~UART_MCR_DTR; if (clr & TIOCM_OUT1) priv->mcr &= ~UART_MCR_OUT1; if (clr & TIOCM_OUT2) priv->mcr &= ~UART_MCR_OUT2; ark3116_write_reg(port->serial, UART_MCR, priv->mcr); mutex_unlock(&priv->hw_lock); return 0; } static void ark3116_break_ctl(struct tty_struct *tty, int break_state) { struct usb_serial_port *port = tty->driver_data; struct ark3116_private *priv = usb_get_serial_port_data(port); /* LCR is also used for other things: protect access */ mutex_lock(&priv->hw_lock); if (break_state) priv->lcr |= UART_LCR_SBC; else priv->lcr &= ~UART_LCR_SBC; ark3116_write_reg(port->serial, UART_LCR, priv->lcr); mutex_unlock(&priv->hw_lock); } static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) { struct ark3116_private *priv = usb_get_serial_port_data(port); unsigned long flags; spin_lock_irqsave(&priv->status_lock, flags); priv->msr = msr; spin_unlock_irqrestore(&priv->status_lock, flags); if (msr & UART_MSR_ANY_DELTA) { /* update input line counters */ if (msr & UART_MSR_DCTS) port->icount.cts++; if (msr & UART_MSR_DDSR) port->icount.dsr++; if (msr & UART_MSR_DDCD) port->icount.dcd++; if (msr & UART_MSR_TERI) port->icount.rng++; wake_up_interruptible(&port->delta_msr_wait); } } static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) { struct ark3116_private *priv = usb_get_serial_port_data(port); unsigned long flags; spin_lock_irqsave(&priv->status_lock, flags); /* combine bits */ priv->lsr |= lsr; spin_unlock_irqrestore(&priv->status_lock, flags); if (lsr&UART_LSR_BRK_ERROR_BITS) { if (lsr & UART_LSR_BI) port->icount.brk++; if (lsr & UART_LSR_FE) port->icount.frame++; if (lsr & UART_LSR_PE) port->icount.parity++; if (lsr & UART_LSR_OE) port->icount.overrun++; } } static void ark3116_read_int_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; int status = urb->status; const __u8 *data = urb->transfer_buffer; int result; switch (status) { case -ECONNRESET: case -ENOENT: case -ESHUTDOWN: /* this urb is terminated, clean up */ dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", __func__, status); return; default: dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", __func__, status); break; case 0: /* success */ /* discovered this by trail and error... */ if ((urb->actual_length == 4) && (data[0] == 0xe8)) { const __u8 id = data[1]&UART_IIR_ID; dev_dbg(&port->dev, "%s: iir=%02x\n", __func__, data[1]); if (id == UART_IIR_MSI) { dev_dbg(&port->dev, "%s: msr=%02x\n", __func__, data[3]); ark3116_update_msr(port, data[3]); break; } else if (id == UART_IIR_RLSI) { dev_dbg(&port->dev, "%s: lsr=%02x\n", __func__, data[2]); ark3116_update_lsr(port, data[2]); break; } } /* * Not sure what this data meant... */ usb_serial_debug_data(&port->dev, __func__, urb->actual_length, urb->transfer_buffer); break; } result = usb_submit_urb(urb, GFP_ATOMIC); if (result) dev_err(&urb->dev->dev, "%s - Error %d submitting interrupt urb\n", __func__, result); } /* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. * This means that we cannot be sure which data byte has an associated error * condition, so we report an error for all data in the next bulk read. * * Actually, there might even be a window between the bulk data leaving the * ark and reading/resetting the lsr in the read_bulk_callback where an * interrupt for the next data block could come in. * Without somekind of ordering on the ark, we would have to report the * error for the next block of data as well... * For now, let's pretend this can't happen. */ static void ark3116_process_read_urb(struct urb *urb) { struct usb_serial_port *port = urb->context; struct ark3116_private *priv = usb_get_serial_port_data(port); unsigned char *data = urb->transfer_buffer; char tty_flag = TTY_NORMAL; unsigned long flags; __u32 lsr; /* update line status */ spin_lock_irqsave(&priv->status_lock, flags); lsr = priv->lsr; priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; spin_unlock_irqrestore(&priv->status_lock, flags); if (!urb->actual_length) return; if (lsr & UART_LSR_BRK_ERROR_BITS) { if (lsr & UART_LSR_BI) tty_flag = TTY_BREAK; else if (lsr & UART_LSR_PE) tty_flag = TTY_PARITY; else if (lsr & UART_LSR_FE) tty_flag = TTY_FRAME; /* overrun is special, not associated with a char */ if (lsr & UART_LSR_OE) tty_insert_flip_char(&port->port, 0, TTY_OVERRUN); } tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag, urb->actual_length); tty_flip_buffer_push(&port->port); } static struct usb_serial_driver ark3116_device = { .driver = { .owner = THIS_MODULE, .name = "ark3116", }, .id_table = id_table, .num_ports = 1, .attach = ark3116_attach, .port_probe = ark3116_port_probe, .port_remove = ark3116_port_remove, .set_termios = ark3116_set_termios, .init_termios = ark3116_init_termios, .ioctl = ark3116_ioctl, .tiocmget = ark3116_tiocmget, .tiocmset = ark3116_tiocmset, .get_icount = usb_serial_generic_get_icount, .open = ark3116_open, .close = ark3116_close, .break_ctl = ark3116_break_ctl, .read_int_callback = ark3116_read_int_callback, .process_read_urb = ark3116_process_read_urb, }; static struct usb_serial_driver * const serial_drivers[] = { &ark3116_device, NULL }; module_usb_serial_driver(serial_drivers, id_table); MODULE_LICENSE("GPL"); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); /* * The following describes what I learned from studying the old * ark3116.c driver, disassembling the windows driver, and some lucky * guesses. Since I do not have any datasheet or other * documentation, inaccuracies are almost guaranteed. * * Some specs for the ARK3116 can be found here: * http://web.archive.org/web/20060318000438/ * www.arkmicro.com/en/products/view.php?id=10 * On that page, 2 GPIO pins are mentioned: I assume these are the * OUT1 and OUT2 pins of the UART, so I added support for those * through the MCR. Since the pins are not available on my hardware, * I could not verify this. * Also, it states there is "on-chip hardware flow control". I have * discovered how to enable that. Unfortunately, I do not know how to * enable XON/XOFF (software) flow control, which would need support * from the chip as well to work. Because of the wording on the web * page there is a real possibility the chip simply does not support * software flow control. * * I got my ark3116 as part of a mobile phone adapter cable. On the * PCB, the following numbered contacts are present: * * 1:- +5V * 2:o DTR * 3:i RX * 4:i DCD * 5:o RTS * 6:o TX * 7:i RI * 8:i DSR * 10:- 0V * 11:i CTS * * On my chip, all signals seem to be 3.3V, but 5V tolerant. But that * may be different for the one you have ;-). * * The windows driver limits the registers to 0-F, so I assume there * are actually 16 present on the device. * * On an UART interrupt, 4 bytes of data come in on the interrupt * endpoint. The bytes are 0xe8 IIR LSR MSR. * * The baudrate seems to be generated from the 12MHz crystal, using * 4-times subsampling. So quot=12e6/(4*baud). Also see description * of register E. * * Registers 0-7: * These seem to be the same as for a regular 16450. The FCR is set * to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between * the UART and the USB bridge/DMA engine. * * Register 8: * By trial and error, I found out that bit 0 enables hardware CTS, * stopping TX when CTS is +5V. Bit 1 does the same for RTS, making * RTS +5V when the 3116 cannot transfer the data to the USB bus * (verified by disabling the reading URB). Note that as far as I can * tell, the windows driver does NOT use this, so there might be some * hardware bug or something. * * According to a patch provided here * (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used * as an IrDA dongle. Since I do not have such a thing, I could not * investigate that aspect. However, I can speculate ;-). * * - IrDA encodes data differently than RS232. Most likely, one of * the bits in registers 9..E enables the IR ENDEC (encoder/decoder). * - Depending on the IR transceiver, the input and output need to be * inverted, so there are probably bits for that as well. * - IrDA is half-duplex, so there should be a bit for selecting that. * * This still leaves at least two registers unaccounted for. Perhaps * The chip can do XON/XOFF or CRC in HW? * * Register 9: * Set to 0x00 for IrDA, when the baudrate is initialised. * * Register A: * Set to 0x01 for IrDA, at init. * * Register B: * Set to 0x01 for IrDA, 0x00 for RS232, at init. * * Register C: * Set to 00 for IrDA, at init. * * Register D: * Set to 0x41 for IrDA, at init. * * Register E: * Somekind of baudrate override. The windows driver seems to set * this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. * Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, * it could be somekind of subdivisor thingy. * However,it does not seem to do anything: selecting 921600 (divisor 3, * reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would * work, but they don't. * * Register F: unknown */