[PATCH v4 4/4] ARM: dts: Add exynos5250-spring device tree

Hi Tomasz,

Am 31.07.2014 21:05, schrieb Tomasz Figa:

Hi Andreas,

Sorry for joining the party a bit late, but there were patches with less
people involved so I preferred to review them first.

You can find my comments inline.

On 31.07.2014 18:08, Andreas F?rber wrote:

quoted

Adds initial support for the HP Chromebook 11.

[snip]

quoted

+	gpio-keys {
+		compatible = "gpio-keys";
+		pinctrl-names = "default";
+		pinctrl-0 = <&power_key_irq>, <&lid_irq>;
+
+		power {
+			label = "Power";
+			gpios = <&gpx1 3 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_POWER>;

I assume the key is debounced in hardware, so there is no need for
debounce-interval here. Is this correct?

You're asking the wrong person... This is copied from
-cros-common/-snow. Downstream 3.8 does not have a debounce-interval
property.

quoted

+			gpio-key,wakeup;
+		};
+
+		lid-switch {
+			label = "Lid";
+			gpios = <&gpx3 5 GPIO_ACTIVE_LOW>;
+			linux,input-type = <5>; /* EV_SW */
+			linux,code = <0>; /* SW_LID */
+			debounce-interval = <1>;
+			gpio-key,wakeup;
+		};
+	};
+
+	usb3_vbus_reg: regulator-usb3 {
+		compatible = "regulator-fixed";
+		regulator-name = "P5.0V_USB3CON";
+		regulator-min-microvolt = <5000000>;
+		regulator-max-microvolt = <5000000>;
+		gpio = <&gpe1 0 GPIO_ACTIVE_LOW>;
+		enable-active-high;
+	};
+
+	usb at 12110000 {

Since this is a brand new dts file, it should use the reference based
syntax, which would be something like

&usbhost {
	...
};

below the / { ... }; block.

You will find that I already did that for all nodes that have a label.
Since there are lots of usb nodes, please suggest specific label names.

I originally tried to stay out of existing code, then I was asked to fix
-cros-common, clean up -snow too, now the SoC, ... ;)

quoted

+		samsung,vbus-gpio = <&gpx1 1 GPIO_ACTIVE_HIGH>;
+	};
+
+	usb-hub {
+		compatible = "smsc,usb3503a";
+		reset-gpios = <&hsic_reset>;

Hmm, why a -gpios property points to a pinctrl node? Shouldn't there be
a phandle to GPIO bank + GPIO specifier instead?

Dunno, can change it. Can I just copy the gpio property from the
regulator above?

quoted

+	};
+
+	fixed-rate-clocks {
+		xxti {
+			compatible = "samsung,clock-xxti";
+			clock-frequency = <24000000>;
+		};
+	};

This is also referencing a node from higher level, so it should be done
using a reference.

quoted

+
+	hdmi {
+		hpd-gpio = <&gpx3 7 GPIO_ACTIVE_HIGH>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&hdmi_hpd_irq>;
+		phy = <&hdmiphy>;
+		ddc = <&i2c_2>;
+		hdmi-en-supply = <&s5m_ldo8_reg>;
+		vdd-supply = <&s5m_ldo8_reg>;
+		vdd_osc-supply = <&s5m_ldo10_reg>;
+		vdd_pll-supply = <&s5m_ldo8_reg>;
+	};

Ditto.

hdmi?

quoted

+
+	fimd at 14400000 {
+		status = "okay";
+		samsung,invert-vclk;
+	};

Ditto.

fimd?

quoted

+
+	dp-controller at 145B0000 {
+		status = "okay";
+		pinctrl-names = "default";
+		pinctrl-0 = <&dp_hpd>;
+		samsung,color-space = <0>;
+		samsung,dynamic-range = <0>;
+		samsung,ycbcr-coeff = <0>;
+		samsung,color-depth = <1>;
+		samsung,link-rate = <0x0a>;
+		samsung,lane-count = <1>;
+		samsung,hpd-gpio = <&gpc3 0 GPIO_ACTIVE_HIGH>;
+	};

Ditto.

dp_controller? display_port_controller?

quoted

+};
+
+&dp_hpd {
+	samsung,pins = "gpc3-0";
+	samsung,pin-function = <0>;
+	samsung,pin-pud = <3>;
+	samsung,pin-drv = <0>;
+};

Hmm, what node is this referencing? I believe this should rather
reference the pin controller and add a new board-specific pinconf/pinmux
group instead....

It's a -pinctrl node. See v3->v4 change log and discussion on v3.

quoted

+
+&i2c_0 {
+	status = "okay";
+	samsung,i2c-sda-delay = <100>;
+	samsung,i2c-max-bus-freq = <378000>;

[snip]

quoted

+/*
+ * Disabled pullups since external part has its own pullups and
+ * double-pulling gets us out of spec in some cases.
+ */
+&i2c2_bus {
+	samsung,pin-pud = <0>;
+};

OK, here overriding a generic pinconf group is justified and nicely
explained by a comment.

You seem to assume that I actually understand these things. ;)
Just copied from -cros-common/-snow.

quoted

+
+&i2c_2 {
+	status = "okay";
+	samsung,i2c-sda-delay = <100>;
+	samsung,i2c-max-bus-freq = <66000>;
+
+	hdmiddc at 50 {
+		compatible = "samsung,exynos4210-hdmiddc";
+		reg = <0x50>;
+	};

I don't think this matches current Exynos HDMI bindings, which I believe
have been changed to just take a phandle to i2c bus instead.

Copied from -cros-common/-snow.

quoted

+};
+
+&i2c_3 {
+	status = "okay";
+	samsung,i2c-sda-delay = <100>;
+	samsung,i2c-max-bus-freq = <66000>;
+};

[snip]

quoted

+&sd1_clk {
+	samsung,pin-drv = <0>;
+};
+
+&sd1_cmd {
+	samsung,pin-pud = <3>;
+	samsung,pin-drv = <0>;
+};
+
+&sd1_cd {
+	samsung,pin-drv = <0>;
+};
+
+&sd1_bus4 {
+	samsung,pin-drv = <0>;
+};

Here generic settings are being overridden, so it might be a good idea
to explain why, like with i2c pull-up above.

Snow does not have an explanation either, so please suggest what comment
you'd like to see. Consider me just a user with no specs. :)

Cheers,
Andreas

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