Re: [PATCH v4 2/5] mfd: lm3533: Support initialization from Device Tree

On Wed, 04 Jan 2017, Bjorn Andersson wrote:

On Wed 04 Jan 03:54 PST 2017, Lee Jones wrote:

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On Mon, 26 Dec 2016, Bjorn Andersson wrote:

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From: Bjorn Andersson <redacted>

Implement support for initialization of the lm3533 driver core and
probing child devices from Device Tree.

[..]

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@@ -512,6 +514,11 @@ static int lm3533_device_init(struct lm3533 *lm3533)
 	lm3533_device_bl_init(lm3533);
 	lm3533_device_led_init(lm3533);
 
+	if (lm3533->dev->of_node) {
+		of_platform_populate(lm3533->dev->of_node, NULL, NULL,
+				     lm3533->dev);
+	}

I think it's save to call of_platform_populate(), even if !of_node.
It will just fail and return an error code, which you are ignoring
anyway.

I thought so too, but that's apparently how you trigger probing children
of the root node. So we're stuck with a conditional.

Ah, so this is to protect against the case where DT is present, but a
node for this device is not (or is disabled), so is left unprobed.
Then the bind is initiated via I2C?  Or something else?

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 static int lm3533_i2c_probe(struct i2c_client *i2c,
 					const struct i2c_device_id *id)
 {

[..]

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+	if (i2c->dev.of_node) {

I'd prefer this check to be placed in lm3533_pdata_from_of_node().

Just return silently if !dev->of_node.

I agree, will update this.

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+		ret = lm3533_pdata_from_of_node(lm3533->dev);
+		if (ret < 0)
+			return ret;
+	}
+
 	return lm3533_device_init(lm3533);
 }
 

Regards,
Bjorn

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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