diff options
Diffstat (limited to 'grub-core/bus/usb/serial/ftdi.c')
| -rw-r--r-- | grub-core/bus/usb/serial/ftdi.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/grub-core/bus/usb/serial/ftdi.c b/grub-core/bus/usb/serial/ftdi.c new file mode 100644 index 0000000..1a99cba --- /dev/null +++ b/grub-core/bus/usb/serial/ftdi.c @@ -0,0 +1,218 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2000,2001,2002,2003,2004,2005,2007,2008,2009,2010 Free Software Foundation, Inc. + * + * GRUB 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 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/serial.h> +#include <grub/types.h> +#include <grub/dl.h> +#include <grub/misc.h> +#include <grub/mm.h> +#include <grub/usb.h> +#include <grub/usbserial.h> +#include <grub/i18n.h> + +GRUB_MOD_LICENSE ("GPLv3+"); + +enum + { + GRUB_FTDI_MODEM_CTRL = 0x01, + GRUB_FTDI_FLOW_CTRL = 0x02, + GRUB_FTDI_SPEED_CTRL = 0x03, + GRUB_FTDI_DATA_CTRL = 0x04 + }; + +#define GRUB_FTDI_MODEM_CTRL_DTRRTS 3 +#define GRUB_FTDI_FLOW_CTRL_DTRRTS 3 + +/* Convert speed to divisor. */ +static grub_uint32_t +get_divisor (unsigned int speed) +{ + unsigned int i; + + /* The structure for speed vs. divisor. */ + struct divisor + { + unsigned int speed; + grub_uint32_t div; + }; + + /* The table which lists common configurations. */ + /* Computed with a division formula with 3MHz as base frequency. */ + static struct divisor divisor_tab[] = + { + { 2400, 0x04e2 }, + { 4800, 0x0271 }, + { 9600, 0x4138 }, + { 19200, 0x809c }, + { 38400, 0xc04e }, + { 57600, 0xc034 }, + { 115200, 0x001a } + }; + + /* Set the baud rate. */ + for (i = 0; i < ARRAY_SIZE (divisor_tab); i++) + if (divisor_tab[i].speed == speed) + return divisor_tab[i].div; + return 0; +} + +static void +real_config (struct grub_serial_port *port) +{ + grub_uint32_t divisor; + const grub_uint16_t parities[] = { + [GRUB_SERIAL_PARITY_NONE] = 0x0000, + [GRUB_SERIAL_PARITY_ODD] = 0x0100, + [GRUB_SERIAL_PARITY_EVEN] = 0x0200 + }; + const grub_uint16_t stop_bits[] = { + [GRUB_SERIAL_STOP_BITS_1] = 0x0000, + [GRUB_SERIAL_STOP_BITS_1_5] = 0x0800, + [GRUB_SERIAL_STOP_BITS_2] = 0x1000, + }; + + if (port->configured) + return; + + grub_usb_control_msg (port->usbdev, GRUB_USB_REQTYPE_VENDOR_OUT, + GRUB_FTDI_MODEM_CTRL, + port->config.rtscts ? GRUB_FTDI_MODEM_CTRL_DTRRTS : 0, + 0, 0, 0); + + grub_usb_control_msg (port->usbdev, GRUB_USB_REQTYPE_VENDOR_OUT, + GRUB_FTDI_FLOW_CTRL, + port->config.rtscts ? GRUB_FTDI_FLOW_CTRL_DTRRTS : 0, + 0, 0, 0); + + divisor = get_divisor (port->config.speed); + grub_usb_control_msg (port->usbdev, GRUB_USB_REQTYPE_VENDOR_OUT, + GRUB_FTDI_SPEED_CTRL, + divisor & 0xffff, divisor >> 16, 0, 0); + + grub_usb_control_msg (port->usbdev, GRUB_USB_REQTYPE_VENDOR_OUT, + GRUB_FTDI_DATA_CTRL, + parities[port->config.parity] + | stop_bits[port->config.stop_bits] + | port->config.word_len, 0, 0, 0); + + port->configured = 1; +} + +/* Fetch a key. */ +static int +ftdi_hw_fetch (struct grub_serial_port *port) +{ + real_config (port); + + return grub_usbserial_fetch (port, 2); +} + +/* Put a character. */ +static void +ftdi_hw_put (struct grub_serial_port *port, const int c) +{ + char cc = c; + + real_config (port); + + grub_usb_bulk_write (port->usbdev, port->out_endp, 1, &cc); +} + +static grub_err_t +ftdi_hw_configure (struct grub_serial_port *port, + struct grub_serial_config *config) +{ + grub_uint16_t divisor; + + divisor = get_divisor (config->speed); + if (divisor == 0) + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unsupported serial port speed")); + + if (config->parity != GRUB_SERIAL_PARITY_NONE + && config->parity != GRUB_SERIAL_PARITY_ODD + && config->parity != GRUB_SERIAL_PARITY_EVEN) + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unsupported serial port parity")); + + if (config->stop_bits != GRUB_SERIAL_STOP_BITS_1 + && config->stop_bits != GRUB_SERIAL_STOP_BITS_1_5 + && config->stop_bits != GRUB_SERIAL_STOP_BITS_2) + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unsupported serial port stop bits number")); + + if (config->word_len < 5 || config->word_len > 8) + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unsupported serial port word length")); + + port->config = *config; + port->configured = 0; + + return GRUB_ERR_NONE; +} + +static struct grub_serial_driver grub_ftdi_driver = + { + .configure = ftdi_hw_configure, + .fetch = ftdi_hw_fetch, + .put = ftdi_hw_put, + .fini = grub_usbserial_fini + }; + +static const struct +{ + grub_uint16_t vendor, product; +} products[] = + { + {0x0403, 0x6001} /* QEMU virtual USBserial. */ + }; + +static int +grub_ftdi_attach (grub_usb_device_t usbdev, int configno, int interfno) +{ + unsigned j; + + for (j = 0; j < ARRAY_SIZE (products); j++) + if (usbdev->descdev.vendorid == products[j].vendor + && usbdev->descdev.prodid == products[j].product) + break; + if (j == ARRAY_SIZE (products)) + return 0; + + return grub_usbserial_attach (usbdev, configno, interfno, + &grub_ftdi_driver, + GRUB_USB_SERIAL_ENDPOINT_LAST_MATCHING, + GRUB_USB_SERIAL_ENDPOINT_LAST_MATCHING); +} + +static struct grub_usb_attach_desc attach_hook = +{ + .class = 0xff, + .hook = grub_ftdi_attach +}; + +GRUB_MOD_INIT(usbserial_ftdi) +{ + grub_usb_register_attach_hook_class (&attach_hook); +} + +GRUB_MOD_FINI(usbserial_ftdi) +{ + grub_serial_unregister_driver (&grub_ftdi_driver); + grub_usb_unregister_attach_hook_class (&attach_hook); +} |