ARM: tegra20: add funcmux for exposing UART over uSD slot on Tegra 20

UART-A can be exposed through uSD, this was tested on Transformer T20
but should work on all Ventana-based boards.

TX is exported on SDD pingroup corresponding to uSD CLK pin
RX is exported on SDB which is CMD pin in uSD slot

Signed-off-by: Artur Kowalski <arturkow2000@gmail.com>
Reviewed-by: Svyatoslav Ryhel <clamor95@gmail.com>
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>

diff --git a/arch/arm/include/asm/arch-tegra20/funcmux.h b/arch/arm/include/asm/arch-tegra20/funcmux.h
index e9e96c1..bafcf85 100644 (file)
--- a/arch/arm/include/asm/arch-tegra20/funcmux.h
+++ b/arch/arm/include/asm/arch-tegra20/funcmux.h
@@ -19,6 +19,7 @@ enum {
        FUNCMUX_UART1_UAA_UAB,
        FUNCMUX_UART1_GPU,
        FUNCMUX_UART1_SDIO1,
+       FUNCMUX_UART1_SDB_SDD,
        FUNCMUX_UART2_UAD = 0,
        FUNCMUX_UART4_GMC = 0,
 

diff --git a/arch/arm/mach-tegra/board.c b/arch/arm/mach-tegra/board.c
index 8c946f0..4835824 100644 (file)
--- a/arch/arm/mach-tegra/board.c
+++ b/arch/arm/mach-tegra/board.c
@@ -169,6 +169,8 @@ static int uart_configs[] = {
        FUNCMUX_UART1_GPU,
  #elif defined(CONFIG_TEGRA_UARTA_SDIO1)
        FUNCMUX_UART1_SDIO1,
+ #elif defined(CONFIG_TEGRA_UARTA_SDB_SDD)
+       FUNCMUX_UART1_SDB_SDD,
  #else
        FUNCMUX_UART1_IRRX_IRTX,
 #endif

diff --git a/arch/arm/mach-tegra/tegra20/Kconfig b/arch/arm/mach-tegra/tegra20/Kconfig
index 6367837..a79fdc2 100644 (file)
--- a/arch/arm/mach-tegra/tegra20/Kconfig
+++ b/arch/arm/mach-tegra/tegra20/Kconfig
@@ -17,6 +17,9 @@ config TEGRA_UARTA_GPU
 config TEGRA_UARTA_SDIO1
        bool
 
+config TEGRA_UARTA_SDB_SDD
+       bool
+
 choice
        prompt "Tegra20 board select"
        optional

diff --git a/drivers/pinctrl/tegra/funcmux-tegra20.c b/drivers/pinctrl/tegra/funcmux-tegra20.c
index 951ae19..f60d5aa 100644 (file)
--- a/drivers/pinctrl/tegra/funcmux-tegra20.c
+++ b/drivers/pinctrl/tegra/funcmux-tegra20.c
@@ -62,8 +62,15 @@ int funcmux_select(enum periph_id id, int config)
                        pinmux_tristate_disable(PMUX_PINGRP_SDIO1);
                        bad_config = 0;
                        break;
+               case FUNCMUX_UART1_SDB_SDD:
+                       pinmux_set_func(PMUX_PINGRP_SDB, PMUX_FUNC_UARTA);
+                       pinmux_set_func(PMUX_PINGRP_SDD, PMUX_FUNC_UARTA);
+                       pinmux_tristate_disable(PMUX_PINGRP_SDB);
+                       pinmux_tristate_disable(PMUX_PINGRP_SDD);
+                       bad_config = 0;
+                       break;
                }
-               if (!bad_config) {
+               if (!bad_config && config != FUNCMUX_UART1_SDB_SDD) {
                        /*
                         * Tegra appears to boot with function UARTA pre-
                         * selected on mux group SDB. If two mux groups are