Re: [RFC 2.6.27 1/1] gpiolib: add support for batch set of pins

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Dec 30, 2008 at 11:55 PM, Robin Getz <rgetz@xxxxxxxxxxxxxxxxxxxx> wrote:
> Yeah, I hadn't thought about spanning more than one gpio_chip. That's a good
> point.

The currently posted code already supports spanning more than one gpio_chip.

+       do {
+               chip = gpio_to_chip(gpio + i);
+               WARN_ON(extra_checks && chip->can_sleep);
+
+               if (!chip->set_bus) {
+                       while (((gpio + i) < (chip->base + chip->ngpio))
+                               && bitwidth) {
+                               value = values & (1 << i);
+                               chip->set(chip, gpio + i - chip->base, value);
+                               i++;
+                               bitwidth--;
+                       }
+               } else {
+                       value = values >> i; /* shift off the used stuff */
+                       remwidth = ((chip->base + (int) chip->ngpio) -
+                                       ((int) gpio + i));
+                       width = min(bitwidth, remwidth);
+
+                       chip->set_bus(chip, gpio + i - chip->base, value,
+                                       width);
+                       i += width;
+                       bitwidth -= width;
+               }
+       } while (bitwidth);
--
To unsubscribe from this list: send the line "unsubscribe linux-embedded" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Gstreamer Embedded]     [Linux MMC Devel]     [U-Boot V2]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux ARM Kernel]     [Linux OMAP]     [Linux SCSI]

  Powered by Linux