On Mon, Jun 22, 2015 at 11:36 AM, Eddie Huang [off-list ref] wrote:

Hi Dan,

On Thu, 2015-06-18 at 23:16 +0800, Daniel Kurtz wrote:

quoted

On Wed, Jun 17, 2015 at 11:08 PM, Eddie Huang [off-list ref] wrote:

quoted

Add MT8173 I2C device nodes, include I2C controllers and pins.
MT8173 has six I2C controllers, from i2c0 to i2c6, exclude i2c5.
The 6th I2C controller register base doesn't next to 5th I2C,
and there is a hardware between 5th and 6th I2C controller. So
SoC designer name 6th controller as "i2c6", not "i2c5".

Signed-off-by: Eddie Huang <eddie.huang@mediatek.com>
---
 arch/arm64/boot/dts/mediatek/mt8173.dtsi | 144 +++++++++++++++++++++++++++++++
 1 file changed, 144 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
index b52ec43..1816c8f 100644
--- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi

@@ -158,6 +158,54 @@
                        interrupts = <GIC_SPI 145 IRQ_TYPE_LEVEL_HIGH>,
                                                <GIC_SPI 146 IRQ_TYPE_LEVEL_HIGH>,
                                                <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>;
+
+                       i2c0_pins_a: i2c0 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_45_SDA0__FUNC_SDA0>,
+                                                <MT8173_PIN_46_SCL0__FUNC_SCL0>;
+                                       bias-disable;
+                               };
+                       };
+
+                       i2c1_pins_a: i2c1 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_125_SDA1__FUNC_SDA1>,
+                                                <MT8173_PIN_126_SCL1__FUNC_SCL1>;
+                                       bias-disable;
+                               };
+                       };
+
+                       i2c2_pins_a: i2c2 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_43_SDA2__FUNC_SDA2>,
+                                                <MT8173_PIN_44_SCL2__FUNC_SCL2>;
+                                       bias-disable;
+                               };
+                       };
+
+                       i2c3_pins_a: i2c3 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_106_SDA3__FUNC_SDA3>,
+                                                <MT8173_PIN_107_SCL3__FUNC_SCL3>;
+                                       bias-disable;
+                               };
+                       };
+
+                       i2c4_pins_a: i2c4 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_133_SDA4__FUNC_SDA4>,
+                                                <MT8173_PIN_134_SCL4__FUNC_SCL4>;
+                                       bias-disable;
+                               };
+                       };
+
+                       i2c6_pins_a: i2c6 {
+                               pins1 {
+                                       pinmux = <MT8173_PIN_100_MSDC2_DAT0__FUNC_SDA5>,
+                                                <MT8173_PIN_101_MSDC2_DAT1__FUNC_SCL5>;
+                                       bias-disable;
+                               };
+                       };
                };

                watchdog: watchdog at 10007000 {

@@ -229,6 +277,102 @@
                        clocks = <&uart_clk>;
                        status = "disabled";
                };
+
+               i2c0: i2c at 11007000 {
+                       compatible = "mediatek,mt8173-i2c";
+                       reg = <0 0x11007000 0 0x70>,
+                             <0 0x11000100 0 0x80>;
+                       interrupts = <GIC_SPI 76 IRQ_TYPE_LEVEL_LOW>;
+                       clock-div = <16>;

According to the i2c-mt6577 dt binding:
   - clock-div: the fixed value for frequency divider of clock source in i2c
     module. Each IC may be different.

For other drivers I've seen this kind of hardware-specific value
implemented as a table in the driver that is indexed based on the
compatible.

Any particular reason to specify it here in every device tree node instead?

If put in device tree, it is not necessary to add new compatible if new
SoC has the same I2C controller hardware except clock-div.The benefit is
keep driver clean, but the side-effect is add clock-div in device node.I
assume clock-div has the same concept of clock, so I put in device tree.

Sounds reasonable to me.  This patch is:

Reviewed-by: Daniel Kurtz <redacted>

Eddie
Thanks