[U-Boot] [PATCH] OMAP3: BeagleBoard: Enable pullups on i2c2.

Jason Kridner jkridner at beagleboard.org
Thu Mar 3 17:44:27 CET 2011


From: Steve Kipisz <s-kipisz2 at ti.com>

This allows the reading of EEPROMS on the expansion bus without adding
external pull-ups.
---
v2 updates
 * Updated per http://patchwork.ozlabs.org/patch/71997/
 * Added description
 * Used OMAP34XX_CTRL_BASE
 * Used structure and writel to perform write

Signed-off-by: Jason Kridner <jkridner at beagleboard.org>
---
 arch/arm/include/asm/arch-omap3/omap3.h |   16 ++++++++++++++++
 board/ti/beagle/beagle.c                |    4 ++++
 2 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/arch/arm/include/asm/arch-omap3/omap3.h b/arch/arm/include/asm/arch-omap3/omap3.h
index 3957c79..88454f2 100644
--- a/arch/arm/include/asm/arch-omap3/omap3.h
+++ b/arch/arm/include/asm/arch-omap3/omap3.h
@@ -50,6 +50,22 @@
 /* CONTROL */
 #define OMAP34XX_CTRL_BASE		(OMAP34XX_L4_IO_BASE + 0x2000)
 
+#ifndef __ASSEMBLY__
+
+/* Signal Integrity Parameter Control Registers */
+struct control_prog_io {
+	unsigned char res[0x408];
+	unsigned int io2;		/* 0x408 */
+	unsigned char res2[0x38];
+	unsigned int io0;		/* 0x444 */
+	unsigned int io1;		/* 0x448 */
+};
+
+#endif /* __ASSEMBLY__ */
+
+/* Bit definition for CONTROL_PROG_IO1 */
+#define PRG_I2C2_PULLUPRESX		0x00000001
+
 /* UART */
 #define OMAP34XX_UART1			(OMAP34XX_L4_IO_BASE + 0x6a000)
 #define OMAP34XX_UART2			(OMAP34XX_L4_IO_BASE + 0x6c000)
diff --git a/board/ti/beagle/beagle.c b/board/ti/beagle/beagle.c
index 929461c..7ba98f1 100644
--- a/board/ti/beagle/beagle.c
+++ b/board/ti/beagle/beagle.c
@@ -148,6 +148,10 @@ int misc_init_r(void)
 {
 	struct gpio *gpio5_base = (struct gpio *)OMAP34XX_GPIO5_BASE;
 	struct gpio *gpio6_base = (struct gpio *)OMAP34XX_GPIO6_BASE;
+	struct prog_io *prog_io_base = (struct gpio *)OMAP34XX_CTRL_BASE;
+
+	/* Enable i2c2 pullup resisters */
+	writel(~(PRG_I2C2_PULLUPRESX), &prog_io_base->io1);
 
 	switch (get_board_revision()) {
 	case REVISION_AXBX:
-- 
1.5.6.4



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