mts-io: standardize lookup of pin name by attribute name

	1 set of functions for ap gpio pin store and show
	each type of card defines a callback that specifies the mapping of attribute names to pin names

1 files changed, 86 insertions, 0 deletions

diff --git a/io-module/mtac.c b/io-module/mtac.c
index 99e2ce7..1c88b40 100644
--- a/io-module/mtac.c
+++ b/io-module/mtac.c
@@ -111,3 +111,89 @@ static bool ap_add_product_info_attributes(int port, int type) {
 
 	return true;
 }
+
+struct gpio_pin *ap_gpio_pin_by_attr_name(const char *name) {
+	struct gpio_pin *pin;
+	char *pin_attr_name;
+	long port;
+	int port_index;
+	char *colon;
+
+	colon = strstr(name, ":");
+	if (colon && ++colon) {
+		if (kstrtol(colon, 10, &port)) {
+			log_error("kstrtol failed on [%s]", colon);
+			return NULL;
+		}
+	} else {
+		log_error("could not read port from attr name [%s]", name);
+		return NULL;
+	}
+	port_index = port - 1;
+
+	pin_attr_name = port_info[port_index]->gpio_pin_name_by_attr_name(name);
+
+	for (pin = gpio_pins; *pin->name; pin++) {
+		if (!strcmp(pin->pin.label, pin_attr_name)) {
+			return pin;
+		}
+	}
+
+	log_error("pin with attr name [%s] not found", name);
+	return NULL;
+}
+
+static ssize_t mts_attr_show_ap_gpio_pin(struct kobject *kobj,
+			struct kobj_attribute *attr,
+			char *buf)
+{
+	int value;
+	struct gpio_pin *pin = ap_gpio_pin_by_attr_name(attr->attr.name);
+
+	if (!pin) {
+		return -ENODEV;
+	}
+
+	mutex_lock(&mts_io_mutex);
+
+	value = gpio_get_value(pin->pin.gpio);
+
+	mutex_unlock(&mts_io_mutex);
+
+	if (value < 0) {
+		return value;
+	}
+
+	if (pin->active_low) {
+		value = !value;
+	}
+
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t mts_attr_store_ap_gpio_pin(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	int value;
+	struct gpio_pin *pin = ap_gpio_pin_by_attr_name(attr->attr.name);
+
+	if (!pin) {
+		return -ENODEV;
+	}
+
+	if (sscanf(buf, "%i", &value) != 1) {
+		return -EINVAL;
+	}
+
+	if (pin->active_low) {
+		value = !value;
+	}
+
+	mutex_lock(&mts_io_mutex);
+
+	gpio_set_value(pin->pin.gpio, value);
+
+	mutex_unlock(&mts_io_mutex);
+
+	return count;
+}