[U-Boot] [PATCH] AT91: add option to enable pullups in at91sam9260_devices.c

[Reinhard Meyer]

Signed-off-by: Reinhard Meyer <u-boot at emk-elektronik.de>
---
 arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c |   35 +++++++++++++++------
 1 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c b/arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c
index 2d88481..87b0442 100644
--- a/arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c
+++ b/arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c
@@ -28,12 +28,27 @@
 #include <asm/arch/gpio.h>
 #include <asm/arch/io.h>
 
+/*
+ * if CONFIG_AT91_GPIO_PULLUP ist set, keep pullups on on all
+ * peripheral pins. Good to have if hardware is soldered optionally
+ * or in case of SPI no slave is selected. Avoid lines to float
+ * needlessly. Use a short local PUP define.
+ *
+ * Due to errata "TXD floats when CTS is inactive" pullups are always
+ * on for TXD pins.
+ */
+#ifdef CONFIG_AT91_GPIO_PULLUP
+# define PUP CONFIG_AT91_GPIO_PULLUP
+#else
+# define PUP 0
+#endif
+
 void at91_serial0_hw_init(void)
 {
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
 	at91_set_a_periph(AT91_PIO_PORTB, 4, 1);		/* TXD0 */
-	at91_set_a_periph(AT91_PIO_PORTB, 5, 0);		/* RXD0 */
+	at91_set_a_periph(AT91_PIO_PORTB, 5, PUP);		/* RXD0 */
 	writel(1 << AT91SAM9260_ID_US0, &pmc->pcer);
 }
 
@@ -42,7 +57,7 @@ void at91_serial1_hw_init(void)
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
 	at91_set_a_periph(AT91_PIO_PORTB, 6, 1);		/* TXD1 */
-	at91_set_a_periph(AT91_PIO_PORTB, 7, 0);		/* RXD1 */
+	at91_set_a_periph(AT91_PIO_PORTB, 7, PUP);		/* RXD1 */
 	writel(1 << AT91SAM9260_ID_US1, &pmc->pcer);
 }
 
@@ -51,7 +66,7 @@ void at91_serial2_hw_init(void)
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
 	at91_set_a_periph(AT91_PIO_PORTB, 8, 1);		/* TXD2 */
-	at91_set_a_periph(AT91_PIO_PORTB, 9, 0);		/* RXD2 */
+	at91_set_a_periph(AT91_PIO_PORTB, 9, PUP);		/* RXD2 */
 	writel(1 << AT91SAM9260_ID_US2, &pmc->pcer);
 }
 
@@ -59,7 +74,7 @@ void at91_serial3_hw_init(void)
 {
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
-	at91_set_a_periph(AT91_PIO_PORTB, 14, 0);		/* DRXD */
+	at91_set_a_periph(AT91_PIO_PORTB, 14, PUP);		/* DRXD */
 	at91_set_a_periph(AT91_PIO_PORTB, 15, 1);		/* DTXD */
 	writel(1 << AT91_ID_SYS, &pmc->pcer);
 }
@@ -88,9 +103,9 @@ void at91_spi0_hw_init(unsigned long cs_mask)
 {
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
-	at91_set_a_periph(AT91_PIO_PORTA, 0, 0);	/* SPI0_MISO */
-	at91_set_a_periph(AT91_PIO_PORTA, 1, 0);	/* SPI0_MOSI */
-	at91_set_a_periph(AT91_PIO_PORTA, 2, 0);	/* SPI0_SPCK */
+	at91_set_a_periph(AT91_PIO_PORTA, 0, PUP);	/* SPI0_MISO */
+	at91_set_a_periph(AT91_PIO_PORTA, 1, PUP);	/* SPI0_MOSI */
+	at91_set_a_periph(AT91_PIO_PORTA, 2, PUP);	/* SPI0_SPCK */
 
 	/* Enable clock */
 	writel(1 << AT91SAM9260_ID_SPI0, &pmc->pcer);
@@ -125,9 +140,9 @@ void at91_spi1_hw_init(unsigned long cs_mask)
 {
 	at91_pmc_t	*pmc	= (at91_pmc_t *) AT91_PMC_BASE;
 
-	at91_set_a_periph(AT91_PIO_PORTB, 0, 0);	/* SPI1_MISO */
-	at91_set_a_periph(AT91_PIO_PORTB, 1, 0);	/* SPI1_MOSI */
-	at91_set_a_periph(AT91_PIO_PORTB, 2, 0);	/* SPI1_SPCK */
+	at91_set_a_periph(AT91_PIO_PORTB, 0, PUP);	/* SPI1_MISO */
+	at91_set_a_periph(AT91_PIO_PORTB, 1, PUP);	/* SPI1_MOSI */
+	at91_set_a_periph(AT91_PIO_PORTB, 2, PUP);	/* SPI1_SPCK */
 
 	/* Enable clock */
 	writel(1 << AT91SAM9260_ID_SPI1, &pmc->pcer);
-- 
1.5.6.5