diff options
| -rw-r--r-- | arch/arm/cpu/armv7/tegra2/funcmux.c | 60 | ||||
| -rw-r--r-- | arch/arm/include/asm/arch-tegra2/funcmux.h | 3 |
2 files changed, 38 insertions, 25 deletions
diff --git a/arch/arm/cpu/armv7/tegra2/funcmux.c b/arch/arm/cpu/armv7/tegra2/funcmux.c index 140f8a7..d3496c5 100644 --- a/arch/arm/cpu/armv7/tegra2/funcmux.c +++ b/arch/arm/cpu/armv7/tegra2/funcmux.c @@ -26,39 +26,43 @@ int funcmux_select(enum periph_id id, int config) { - if (config != 0) { - debug("%s: invalid config %d for periph_id %d", __func__, - config, id); - return -1; - } + int bad_config = config != 0; + switch (id) { case PERIPH_ID_UART1: - 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 module. 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); + 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: - pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA); - pinmux_tristate_disable(PINGRP_UAD); + if (config == 0) { + pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA); + pinmux_tristate_disable(PINGRP_UAD); + } break; case PERIPH_ID_UART4: - pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD); - pinmux_tristate_disable(PINGRP_GMC); + if (config == 0) { + pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD); + pinmux_tristate_disable(PINGRP_GMC); + } break; default: @@ -66,5 +70,11 @@ int funcmux_select(enum periph_id id, int config) return -1; } + if (bad_config) { + debug("%s: invalid config %d for periph_id %d", __func__, + config, id); + return -1; + } + return 0; } diff --git a/arch/arm/include/asm/arch-tegra2/funcmux.h b/arch/arm/include/asm/arch-tegra2/funcmux.h index 2d724a2..d4f9cfb 100644 --- a/arch/arm/include/asm/arch-tegra2/funcmux.h +++ b/arch/arm/include/asm/arch-tegra2/funcmux.h @@ -32,6 +32,9 @@ * The basic config is 0, and higher numbers indicate different * pinmux settings to bring the peripheral out on other pins, * + * This function also disables tristate for the function's pins, + * so that they operate in normal mode. + * * @param id Peripheral id * @param config Configuration to use (generally 0) * @return 0 if ok, -1 on error (e.g. incorrect id or config) |