Subject: [PATCH RESEND 5/6 v10] gpio: Add device tree support to block GPIO API

From: [email-masked] (Roland Stigge)
Date: Tue, 18 Dec 2012 15:30:23 +0100

Hi Mark,

On 12/17/2012 04:51 PM, Mark Rutland wrote:
>> +static int __devinit gpioblock_of_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *block;
>> +	unsigned *gpios;
>> +	int ngpio;
>> +	int ret;
>> +	struct gpio_block *gb;
>> +
>> +	for_each_available_child_of_node(pdev->dev.of_node, block) {
>> +		int i;
>> +
>> +		ngpio = of_gpio_count(block);
>> +		gpios = kzalloc(ngpio * sizeof(*gpios), GFP_KERNEL);
> 
> What if the block node is malformed? ngpio might be -ENOENT or -EINVAL.

AFAICS, of_gpio_count() always returns at least 0. Both if
CONFIG_OF_GPIO is y, m or n. And called of_gpio_named_count() also
currently doesn't return error values. Further, other drivers using
of_gpio_count() don't expect or catch <0.

However, it's reasonable to guard against of_gpio_count() < 1 since
probing without provided blocks should be void.

Will change this for the next patch update together with your leakage
findings.

Thanks for reporting!

Roland