diff options
Diffstat (limited to 'cccp.c')
| -rw-r--r-- | cccp.c | 68 |
1 files changed, 68 insertions, 0 deletions
@@ -0,0 +1,68 @@ +/* + * Copyright © 2008 Keith Packard <keithp@keithp.com> + * + * 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. + * + * This program 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 this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include "ccdbg.h" + +void +cccp_write(struct ccdbg *dbg, uint8_t mask, uint8_t value) +{ + uint16_t set; + int ret; + + set = (mask) | (value << 8); + dbg->debug_data = (dbg->debug_data & ~mask) | (value & mask); + ret = ioctl(dbg->fd, CP2101_IOCTL_GPIOSET, &set); + if (ret < 0) + perror("CP2101_IOCTL_GPIOSET"); +} + +uint8_t +cccp_read(struct ccdbg *dbg, uint8_t mask) +{ + uint8_t pull_up; + int ret; + uint8_t get; + + /* tri-state the bits of interest */ + pull_up = (~dbg->debug_data) & mask; + if (pull_up) { + cccp_write(dbg, pull_up, pull_up); + } + ret = ioctl(dbg->fd, CP2101_IOCTL_GPIOGET, &get); + if (ret < 0) { + perror("CP2101_IOCTL_GPIOGET"); + get = 0; + } + return get & mask; +} + +void +cccp_init(struct ccdbg *dbg) +{ + /* set all of the GPIOs to a known state */ + cccp_write(dbg, 0xf, 0xf); + dbg->clock = 1; +} + +void +cccp_fini(struct ccdbg *dbg) +{ + /* set all of the GPIOs to a known state */ + cccp_write(dbg, 0xf, 0xf); + dbg->clock = 1; +} |