[PATCH 2/4] [v2] gpiolib: add bitmask for valid GPIO lines

On 12/12/2017 03:58 AM, Andy Shevchenko wrote:

On Fri, 2017-12-01 at 17:28 -0600, Timur Tabi wrote:

quoted

Add support for specifying that some GPIOs within a range are
unavailable.
Some systems have a sparse list of GPIOs, where a range of GPIOs is
specified (usually 0 to n-1), but some subset within that range is
absent or unavailable for whatever reason.

To support this, allow drivers to specify a bitmask of GPIOs that
are present or absent.  Gpiolib will then block access to those that
are absent.

quoted

-	status = gpiochip_irqchip_init_valid_mask(chip);
+	status = gpiochip_init_valid_mask(chip);
  	if (status)
  		goto err_remove_from_list;
  
+	status = gpiochip_irqchip_init_valid_mask(chip);
+	if (status)
+		goto err_remove_valid_mask;

Yes, this way it looks good!

I've discovered that I can remove all this code.  I don't need a valid 
mask, all I need to do is block the request properly.

quoted

+static bool gpiochip_available(const struct gpio_chip *gpiochip,
+			   unsigned int offset)
+{

quoted

+	pr_info("%s:%u offset=%u\n", __func__, __LINE__, offset);

Debug leftover?

Fixed, thanks.

quoted

+
+	/* No mask means all valid */
+	if (likely(!gpiochip->valid_mask))
+		return true;
+
+	return test_bit(offset, gpiochip->valid_mask);

Not sure which one is better
  return test_bit();
or
  return !!test_bit();

I've removed this function also.

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