On 06/28/2012 02:18 PM, Dong Aisheng wrote:

On Thu, Jun 28, 2012 at 08:05:14PM +0800, Marc Kleine-Budde wrote:

quoted

On 06/28/2012 01:46 PM, Shawn Guo wrote:

quoted

On Thu, Jun 28, 2012 at 07:33:28PM +0800, Dong Aisheng wrote:

quoted

quoted

+		phy_stby_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
+							"phy-standby-gpios",
+							0, &flags);
+		if (gpio_is_valid(phy_stby_gpio)) {
+			if (flags == OF_GPIO_ACTIVE_LOW)
+				phy_stby_high = false;
+			err = devm_gpio_request_one(&pdev->dev, phy_stby_gpio,
+						    GPIOF_DIR_OUT,
+						    "phy-standby");
+			if (err) {
+				dev_err(&pdev->dev,
+					"failed to request gpio %d: %d\n",
+					phy_stby_gpio, err);
+				goto failed_gpio;

I checked mx28 evk, it seems the phy only has a STB gpio and shared by both CAN0&CAN1.
I wonder the CAN1 probe may fail here.

It can be managed by dts.  Here is what I have in imx28-evk.dts, where
only can0 has phy-enable-gpios property.


	can0: can at 80032000 {
		pinctrl-names = "default";
		pinctrl-0 = <&can0_pins_a>;
		phy-enable-gpios = <&gpio2 13 0>;
		status = "okay";
	};

	can1: can at 80034000 {
		pinctrl-names = "default";
		pinctrl-0 = <&can1_pins_a>;
		status = "okay";
	};

Will this work if can0 is down and can1 is up?

Can we abstract the transceiver power as a regulator? Or a clock? :P

Hmm, it may not be a power.
For mx28evk, it's a STBY pin.
So it may hard to abstract it as a regulator or clock.

I just talked to Sascha, He pointed out, that there already is regulator
that toggles a gpio (only one, not several). I haven't looked at the
details, but a regulator should solve the "two CAN ports share the same
transceiver/phy" problem.

Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
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