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-rw-r--r--arch/arm/mach-omap1/i2c.c159
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/i2c.c b/arch/arm/mach-omap1/i2c.c
new file mode 100644
index 0000000000..94d3e7883e
--- /dev/null
+++ b/arch/arm/mach-omap1/i2c.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Helper module for board specific I2C bus registration
+ *
+ * Copyright (C) 2009 Nokia Corporation.
+ */
+
+#include <linux/i2c.h>
+#include <linux/platform_data/i2c-omap.h>
+
+#include "mux.h"
+#include "soc.h"
+#include "i2c.h"
+
+#define OMAP_I2C_SIZE 0x3f
+#define OMAP1_I2C_BASE 0xfffb3800
+
+static const char name[] = "omap_i2c";
+
+static struct resource i2c_resources[2] = {
+};
+
+static struct platform_device omap_i2c_devices[1] = {
+};
+
+static void __init omap1_i2c_mux_pins(int bus_id)
+{
+ omap_cfg_reg(I2C_SDA);
+ omap_cfg_reg(I2C_SCL);
+}
+
+int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *pdata,
+ int bus_id)
+{
+ struct platform_device *pdev;
+ struct resource *res;
+
+ if (bus_id > 1)
+ return -EINVAL;
+
+ omap1_i2c_mux_pins(bus_id);
+
+ pdev = &omap_i2c_devices[bus_id - 1];
+ pdev->id = bus_id;
+ pdev->name = name;
+ pdev->num_resources = ARRAY_SIZE(i2c_resources);
+ res = i2c_resources;
+ res[0].start = OMAP1_I2C_BASE;
+ res[0].end = res[0].start + OMAP_I2C_SIZE;
+ res[0].flags = IORESOURCE_MEM;
+ res[1].start = INT_I2C;
+ res[1].flags = IORESOURCE_IRQ;
+ pdev->resource = res;
+
+ /* all OMAP1 have IP version 1 register set */
+ pdata->rev = OMAP_I2C_IP_VERSION_1;
+
+ /* all OMAP1 I2C are implemented like this */
+ pdata->flags = OMAP_I2C_FLAG_NO_FIFO |
+ OMAP_I2C_FLAG_SIMPLE_CLOCK |
+ OMAP_I2C_FLAG_16BIT_DATA_REG |
+ OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK;
+
+ /* how the cpu bus is wired up differs for 7xx only */
+
+ pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_2;
+
+ pdev->dev.platform_data = pdata;
+
+ return platform_device_register(pdev);
+}
+
+#define OMAP_I2C_MAX_CONTROLLERS 4
+static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS];
+
+#define OMAP_I2C_CMDLINE_SETUP (BIT(31))
+
+/**
+ * omap_i2c_bus_setup - Process command line options for the I2C bus speed
+ * @str: String of options
+ *
+ * This function allow to override the default I2C bus speed for given I2C
+ * bus with a command line option.
+ *
+ * Format: i2c_bus=bus_id,clkrate (in kHz)
+ *
+ * Returns 1 on success, 0 otherwise.
+ */
+static int __init omap_i2c_bus_setup(char *str)
+{
+ int ints[3];
+
+ get_options(str, 3, ints);
+ if (ints[0] < 2 || ints[1] < 1 ||
+ ints[1] > OMAP_I2C_MAX_CONTROLLERS)
+ return 0;
+ i2c_pdata[ints[1] - 1].clkrate = ints[2];
+ i2c_pdata[ints[1] - 1].clkrate |= OMAP_I2C_CMDLINE_SETUP;
+
+ return 1;
+}
+__setup("i2c_bus=", omap_i2c_bus_setup);
+
+/*
+ * Register busses defined in command line but that are not registered with
+ * omap_register_i2c_bus from board initialization code.
+ */
+int __init omap_register_i2c_bus_cmdline(void)
+{
+ int i, err = 0;
+
+ for (i = 0; i < ARRAY_SIZE(i2c_pdata); i++)
+ if (i2c_pdata[i].clkrate & OMAP_I2C_CMDLINE_SETUP) {
+ i2c_pdata[i].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
+ err = omap_i2c_add_bus(&i2c_pdata[i], i + 1);
+ if (err)
+ goto out;
+ }
+
+out:
+ return err;
+}
+
+/**
+ * omap_register_i2c_bus - register I2C bus with device descriptors
+ * @bus_id: bus id counting from number 1
+ * @clkrate: clock rate of the bus in kHz
+ * @info: pointer into I2C device descriptor table or NULL
+ * @len: number of descriptors in the table
+ *
+ * Returns 0 on success or an error code.
+ */
+int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
+ struct i2c_board_info const *info,
+ unsigned len)
+{
+ int err;
+
+ BUG_ON(bus_id < 1 || bus_id > OMAP_I2C_MAX_CONTROLLERS);
+
+ if (info) {
+ err = i2c_register_board_info(bus_id, info, len);
+ if (err)
+ return err;
+ }
+
+ if (!i2c_pdata[bus_id - 1].clkrate)
+ i2c_pdata[bus_id - 1].clkrate = clkrate;
+
+ i2c_pdata[bus_id - 1].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
+
+ return omap_i2c_add_bus(&i2c_pdata[bus_id - 1], bus_id);
+}
+
+static int __init omap_i2c_cmdline(void)
+{
+ return omap_register_i2c_bus_cmdline();
+}
+subsys_initcall(omap_i2c_cmdline);