/* * Copyright (c) 2011 The Chromium OS Authors. * See file CREDITS for list of people who contributed to this * project. * * 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 */ /* Tegra2 high-level function multiplexing */ #include #include #include int funcmux_select(enum periph_id id, int config) { int bad_config = config != 0; switch (id) { case PERIPH_ID_UART1: if (config == 0) { pinmux_set_func(PINGRP_IRRX, PMUX_FUNC_UARTA); pinmux_set_func(PINGRP_IRTX, PMUX_FUNC_UARTA); pinmux_tristate_disable(PINGRP_IRRX); pinmux_tristate_disable(PINGRP_IRTX); /* * Tegra appears to boot with function UARTA pre- * selected on mux group SDB. If two mux groups are * both set to the same function, it's unclear which * group's pins drive the RX signals into the HW. * For UARTA, SDB certainly overrides group IRTX in * practice. To solve this, configure some alternative * function on SDB to avoid the conflict. Also, tri- * state the group to avoid driving any signal onto it * until we know what's connected. */ pinmux_tristate_enable(PINGRP_SDB); pinmux_set_func(PINGRP_SDB, PMUX_FUNC_SDIO3); } break; case PERIPH_ID_UART2: if (config == 0) { pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA); pinmux_tristate_disable(PINGRP_UAD); } break; case PERIPH_ID_UART4: if (config == 0) { pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD); pinmux_tristate_disable(PINGRP_GMC); } break; default: debug("%s: invalid periph_id %d", __func__, id); return -1; } if (bad_config) { debug("%s: invalid config %d for periph_id %d", __func__, config, id); return -1; } return 0; }