[U-Boot] [PATCH 7/8] tegra2: spi: Support SPI / UART switch

[Simon Glass]

Add the SPI / UART switch logic into the Tegra2 SPI driver so that it
can co-exist with the NS16550 UART.

Signed-off-by: Simon Glass <sjg at chromium.org>
---
 drivers/spi/tegra2_spi.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/tegra2_spi.c b/drivers/spi/tegra2_spi.c
index c8c20aa..83b36b3 100644
--- a/drivers/spi/tegra2_spi.c
+++ b/drivers/spi/tegra2_spi.c
@@ -24,6 +24,7 @@
 #include <common.h>
 
 #include <malloc.h>
+#include <ns16550.h> /* for NS16550_drain and NS16550_clear */
 #include <spi.h>
 #include <asm/io.h>
 #include <asm/gpio.h>
@@ -31,6 +32,7 @@
 #include <asm/arch/clock.h>
 #include <asm/arch/pinmux.h>
 #include <asm/arch/tegra2_spi.h>
+#include "uart-spi-fix.h"
 
 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
 {
@@ -104,6 +106,12 @@ int spi_claim_bus(struct spi_slave *slave)
 
 void spi_release_bus(struct spi_slave *slave)
 {
+	/*
+	 * We can't release UART_DISABLE and set pinmux to UART4 here since
+	 * some code (e,g, spi_flash_probe) uses printf() while the SPI
+	 * bus is held. That is arguably bad, but it has the advantage of
+	 * already being in the source tree.
+	 */
 }
 
 void spi_cs_activate(struct spi_slave *slave)
@@ -111,6 +119,8 @@ void spi_cs_activate(struct spi_slave *slave)
 	struct spi_tegra *spi = (struct spi_tegra *)TEGRA2_SPI_BASE;
 	u32 val;
 
+	spi_enable();
+
 	/* CS is negated on Tegra, so drive a 1 to get a 0 */
 	val = readl(&spi->command);
 	writel(val | SPI_CMD_CS_VAL, &spi->command);
-- 
1.7.3.1