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-rw-r--r--Documentation/kernel-parameters.txt4
-rw-r--r--arch/arm/plat-omap/i2c.c54
2 files changed, 48 insertions, 10 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 54f21a5c262..d775076d156 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -830,6 +830,10 @@ and is between 256 and 4096 characters. It is defined in the file
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
terminal devices. Valid values: 0..8
+ i2c_bus= [HW] Override the default board specific I2C bus speed
+ Format:
+ <bus_id>,<clkrate>
+
i8042.debug [HW] Toggle i8042 debug mode
i8042.direct [HW] Put keyboard port into non-translated mode
i8042.dumbkbd [HW] Pretend that controller can only read data from
diff --git a/arch/arm/plat-omap/i2c.c b/arch/arm/plat-omap/i2c.c
index 3e95954e2a8..aa70e435fa7 100644
--- a/arch/arm/plat-omap/i2c.c
+++ b/arch/arm/plat-omap/i2c.c
@@ -119,6 +119,46 @@ static void __init omap_i2c_mux_pins(int bus)
omap_cfg_reg(scl);
}
+static int __init omap_i2c_nr_ports(void)
+{
+ int ports = 0;
+
+ if (cpu_class_is_omap1())
+ ports = 1;
+ else if (cpu_is_omap24xx())
+ ports = 2;
+ else if (cpu_is_omap34xx())
+ ports = 3;
+
+ return ports;
+}
+
+/**
+ * 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 ports;
+ int ints[3];
+
+ ports = omap_i2c_nr_ports();
+ get_options(str, 3, ints);
+ if (ints[0] < 2 || ints[1] < 1 || ints[1] > ports)
+ return 0;
+ i2c_rate[ints[1] - 1] = ints[2];
+
+ return 1;
+}
+__setup("i2c_bus=", omap_i2c_bus_setup);
+
/**
* omap_register_i2c_bus - register I2C bus with device descriptors
* @bus_id: bus id counting from number 1
@@ -132,19 +172,12 @@ int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
struct i2c_board_info const *info,
unsigned len)
{
- int ports, err;
+ int 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);
+ BUG_ON(bus_id < 1 || bus_id > omap_i2c_nr_ports());
if (info) {
err = i2c_register_board_info(bus_id, info, len);
@@ -153,7 +186,8 @@ int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
}
pdev = &omap_i2c_devices[bus_id - 1];
- *(u32 *)pdev->dev.platform_data = clkrate;
+ if (i2c_rate[bus_id - 1] == 0)
+ i2c_rate[bus_id - 1] = clkrate;
if (bus_id == 1) {
res = pdev->resource;