tegra3: i2c: Add low level functions for T30

We need these functions to set up the power chip during low-level init.

BUG=chromium-os:21033
TEST=build and boot on Seaboard

Change-Id: I69b9d3c12581e0a71db39b031b9ea2ef4ec184bf
Reviewed-on: http://gerrit.chromium.org/gerrit/8696
Reviewed-by: Che-Liang Chiou <clchiou@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

2 files changed, 54 insertions, 0 deletions

diff --git a/arch/arm/include/asm/arch-tegra/i2c.h b/arch/arm/include/asm/arch-tegra/i2c.h
index 25fb21d3fc8..458cd5ef60b 100644
--- a/arch/arm/include/asm/arch-tegra/i2c.h
+++ b/arch/arm/include/asm/arch-tegra/i2c.h
@@ -168,4 +168,28 @@ struct i2c_ctlr {
 #define I2C_INT_NO_ACK_RANGE			3 : 3
 #define I2C_INT_ARBITRATION_LOST_RANGE		2 : 2
 
+/**
+ * Low level, hopefully temporary, functions to write values to the
+ * Tegra DVC I2C controller. These are used by T30 init, when running
+ * on the AVP CPU, before the Cortex-A9s are up. It is not easy to
+ * have the i2c infrastructure up that early, but we still want to put
+ * this code in the driver
+ */
+
+/**
+ * Write an address (with config) to the DVC I2C
+ *
+ * @param addr		Address to write
+ * @param config	Config to write
+ */
+void tegra_i2c_ll_write_addr(uint addr, uint config);
+
+/**
+ * Write a data word (with config) to the DVC I2C
+ *
+ * @param data		Data to write
+ * @param config	Config to write
+ */
+void tegra_i2c_ll_write_data(uint data, uint config);
+
 #endif
diff --git a/drivers/i2c/tegra_i2c.c b/drivers/i2c/tegra_i2c.c
index c51dd906927..3a94116831b 100644
--- a/drivers/i2c/tegra_i2c.c
+++ b/drivers/i2c/tegra_i2c.c
@@ -32,6 +32,9 @@
 #include <asm/arch/pinmux.h>
 #include <fdt_decode.h>
 
+/* TODO(sjg): This driver has not been tested with Tegra3 yet */
+#ifdef CONFIG_TEGRA2
+
 DECLARE_GLOBAL_DATA_PTR;
 
 static unsigned int i2c_bus_num;
@@ -623,3 +626,30 @@ int i2c_set_bus_num(unsigned int bus)
 	return 0;
 }
 #endif
+
+#else /* not CONFIG_TEGRA2 */
+
+/* Not implemented for now */
+int i2c_init_board(void)
+{
+	printf("i2c support is not available on T30\n");
+	return -1;
+}
+
+#endif /* CONFIG_TEGRA2 */
+
+void tegra_i2c_ll_write_addr(uint addr, uint config)
+{
+	struct i2c_ctlr *reg = (struct i2c_ctlr *)TEGRA_DVC_BASE;
+
+	writel(addr, &reg->cmd_addr0);
+	writel(config, &reg->cnfg);
+}
+
+void tegra_i2c_ll_write_data(uint data, uint config)
+{
+	struct i2c_ctlr *reg = (struct i2c_ctlr *)TEGRA_DVC_BASE;
+
+	writel(data, &reg->cmd_data1);
+	writel(config, &reg->cnfg);
+}