From 7132b9fd68a1c76bf557d56dd62756a6607cf761 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 26 Jan 2015 20:29:37 -0700 Subject: dm: i2c: dts: Support an offset-len device tree property Since U-Boot can support different offset lengths (0-4 bytes), add a device tree property to specify this. This avoids hard-coding it in the driver. Signed-off-by: Simon Glass --- doc/device-tree-bindings/i2c/i2c.txt | 28 ++++++++++++++++++++++++++++ drivers/i2c/i2c-uclass.c | 3 ++- 2 files changed, 30 insertions(+), 1 deletion(-) create mode 100644 doc/device-tree-bindings/i2c/i2c.txt diff --git a/doc/device-tree-bindings/i2c/i2c.txt b/doc/device-tree-bindings/i2c/i2c.txt new file mode 100644 index 0000000..ea918dd --- /dev/null +++ b/doc/device-tree-bindings/i2c/i2c.txt @@ -0,0 +1,28 @@ +U-Boot I2C +---------- + +U-Boot's I2C model has the concept of an offset within a chip (I2C target +device). The offset can be up to 4 bytes long, but is normally 1 byte, +meaning that offsets from 0 to 255 are supported by the chip. This often +corresponds to register numbers. + +Apart from the controller-specific I2C bindings, U-Boot supports a special +property which allows the chip offset length to be selected. + +Optional properties: +- u-boot,i2c-offset-len - length of chip offset in bytes. If omitted the + default value of 1 is used. + + +Example +------- + +i2c4: i2c@12ca0000 { + cros-ec@1e { + reg = <0x1e>; + compatible = "google,cros-ec"; + i2c-max-frequency = <100000>; + u-boot,i2c-offset-len = <0>; + ec-interrupt = <&gpx1 6 GPIO_ACTIVE_LOW>; + }; +}; diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c index 393cd6f..eafa457 100644 --- a/drivers/i2c/i2c-uclass.c +++ b/drivers/i2c/i2c-uclass.c @@ -420,7 +420,8 @@ int i2c_deblock(struct udevice *bus) int i2c_chip_ofdata_to_platdata(const void *blob, int node, struct dm_i2c_chip *chip) { - chip->offset_len = 1; /* default */ + chip->offset_len = fdtdec_get_int(gd->fdt_blob, node, + "u-boot,i2c-offset-len", 1); chip->flags = 0; chip->chip_addr = fdtdec_get_int(gd->fdt_blob, node, "reg", -1); if (chip->chip_addr == -1) { -- cgit v1.1