ARM: OMAP: Add helper module for board specific I2C bus registration

This helper module simplifies I2C bus registration for different OMAP
platforms by doing registration in one place only and to allow board
specific bus configuration like clock rate and number of busses configured.

Helper should cover OMAP processors from first to third generation.

This patch just adds the feature and current implementation cleanup and
board file modifications will be done in following patches.

Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>

2 files changed, 149 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/Makefile b/arch/arm/plat-omap/Makefile
index 2549129..ce17df3 100644
--- a/arch/arm/plat-omap/Makefile
+++ b/arch/arm/plat-omap/Makefile
@@ -19,3 +19,4 @@ obj-$(CONFIG_CPU_FREQ) += cpu-omap.o
 obj-$(CONFIG_OMAP_DM_TIMER) += dmtimer.o
 obj-$(CONFIG_OMAP_DEBUG_DEVICES) += debug-devices.o
 obj-$(CONFIG_OMAP_DEBUG_LEDS) += debug-leds.o
+obj-$(CONFIG_I2C_OMAP) += i2c.o
diff --git a/arch/arm/plat-omap/i2c.c b/arch/arm/plat-omap/i2c.c
new file mode 100644
index 0000000..7990ab1
--- /dev/null
+++ b/arch/arm/plat-omap/i2c.c
@@ -0,0 +1,148 @@
+/*
+ * linux/arch/arm/plat-omap/i2c.c
+ *
+ * Helper module for board specific I2C bus registration
+ *
+ * Copyright (C) 2007 Nokia Corporation.
+ *
+ * Contact: Jarkko Nikula <jarkko.nikula@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <asm/mach-types.h>
+#include <asm/arch/mux.h>
+
+#define OMAP_I2C_SIZE		0x3f
+#define OMAP1_I2C_BASE		0xfffb3800
+#define OMAP2_I2C_BASE1		0x48070000
+#define OMAP2_I2C_BASE2		0x48072000
+#define OMAP2_I2C_BASE3		0x48060000
+
+static const char name[] = "i2c_omap";
+
+#define I2C_RESOURCE_BUILDER(base, irq)			\
+	{						\
+		.start	= (base),			\
+		.end	= (base) + OMAP_I2C_SIZE,	\
+		.flags	= IORESOURCE_MEM,		\
+	},						\
+	{						\
+		.start	= (irq),			\
+		.flags	= IORESOURCE_IRQ,		\
+	},
+
+static struct resource i2c_resources[][2] = {
+	{ I2C_RESOURCE_BUILDER(0, 0) },
+#if	defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
+	{ I2C_RESOURCE_BUILDER(OMAP2_I2C_BASE2, INT_24XX_I2C2_IRQ) },
+#endif
+#if	defined(CONFIG_ARCH_OMAP34XX)
+	{ I2C_RESOURCE_BUILDER(OMAP2_I2C_BASE3, INT_34XX_I2C3_IRQ) },
+#endif
+};
+
+#define I2C_DEV_BUILDER(bus_id, res, data)		\
+	{						\
+		.id	= (bus_id),			\
+		.name	= name,				\
+		.num_resources	= ARRAY_SIZE(res),	\
+		.resource	= (res),		\
+		.dev		= {			\
+			.platform_data	= (data),	\
+		},					\
+	}
+
+static u32 i2c_rate[ARRAY_SIZE(i2c_resources)];
+static struct platform_device omap_i2c_devices[] = {
+	I2C_DEV_BUILDER(1, i2c_resources[0], &i2c_rate[0]),
+#if	defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
+	I2C_DEV_BUILDER(2, i2c_resources[1], &i2c_rate[1]),
+#endif
+#if	defined(CONFIG_ARCH_OMAP34XX)
+	I2C_DEV_BUILDER(3, i2c_resources[2], &i2c_rate[2]),
+#endif
+};
+
+static void __init omap_i2c_mux_pins(int bus_id)
+{
+	/* TODO: Muxing for OMAP3 */
+	switch (bus_id) {
+	case 1:
+		if (cpu_class_is_omap1()) {
+			omap_cfg_reg(I2C_SCL);
+			omap_cfg_reg(I2C_SDA);
+		} else if (cpu_is_omap24xx()) {
+			omap_cfg_reg(M19_24XX_I2C1_SCL);
+			omap_cfg_reg(L15_24XX_I2C1_SDA);
+		}
+		break;
+	case 2:
+		if (cpu_is_omap24xx()) {
+			omap_cfg_reg(J15_24XX_I2C2_SCL);
+			omap_cfg_reg(H19_24XX_I2C2_SDA);
+		}
+		break;
+	}
+}
+
+int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
+			  struct i2c_board_info const *info,
+			  unsigned len)
+{
+	int ports, err;
+	struct platform_device *pdev;
+	struct resource *res;
+	resource_size_t base, irq;
+
+	if (cpu_class_is_omap1())
+		ports = 1;
+	else if (cpu_is_omap24xx())
+		ports = 2;
+	else if (cpu_is_omap34xx())
+		ports = 3;
+
+	BUG_ON(bus_id < 1 || bus_id > ports);
+
+	if (info) {
+		err = i2c_register_board_info(bus_id, info, len);
+		if (err)
+			return err;
+	}
+
+	pdev = &omap_i2c_devices[bus_id - 1];
+	*(u32 *)pdev->dev.platform_data = clkrate;
+
+	if (bus_id == 1) {
+		res = pdev->resource;
+		if (cpu_class_is_omap1()) {
+			base = OMAP1_I2C_BASE;
+			irq = INT_I2C;
+		} else {
+			base = OMAP2_I2C_BASE1;
+			irq = INT_24XX_I2C1_IRQ;
+		}
+		res[0].start = base;
+		res[0].end = base + OMAP_I2C_SIZE;
+		res[1].start = irq;
+	}
+
+	omap_i2c_mux_pins(bus_id);
+	return platform_device_register(pdev);
+}