From e5901c94e32b3533c35511d1acfb7f1587e324ee Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 10 Nov 2014 18:00:21 -0700 Subject: dm: gpio: Add a function to read an ID from a list of GPIOs For board IDs a common approach is to set aside several GPIOs for use in determining the board ID. This can provide information about board features and the revision. Add a function that turns a list of GPIOs into an integer by assigning each GPIO to a single bit. Signed-off-by: Simon Glass --- drivers/gpio/gpio-uclass.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 45e9a5ad22..255700ab18 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -390,6 +390,25 @@ int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize) return 0; } +/* + * get a number comprised of multiple GPIO values. gpio_num_array points to + * the array of gpio pin numbers to scan, terminated by -1. + */ +unsigned gpio_get_values_as_int(const int *gpio_num_array) +{ + int gpio; + unsigned bitmask = 1; + unsigned vector = 0; + + while (bitmask && + ((gpio = *gpio_num_array++) != -1)) { + if (gpio_get_value(gpio)) + vector |= bitmask; + bitmask <<= 1; + } + return vector; +} + /* We need to renumber the GPIOs when any driver is probed/removed */ static int gpio_renumber(struct udevice *removed_dev) { -- cgit v1.2.1