[for-upstream/dovetail 1/2] drivers/gpio: core: introduce helper to find array of gpiochips

[hongzha1]

To find array of gpiochips for non-OF platform

Signed-off-by: hongzha1 <hongzhan.chen at intel.com>
---
 include/cobalt/kernel/rtdm/gpio.h |  4 ++++
 kernel/drivers/gpio/gpio-core.c   | 19 +++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/include/cobalt/kernel/rtdm/gpio.h b/include/cobalt/kernel/rtdm/gpio.h
index c5fb20f25..99772f558 100644
--- a/include/cobalt/kernel/rtdm/gpio.h
+++ b/include/cobalt/kernel/rtdm/gpio.h
@@ -64,6 +64,10 @@ int rtdm_gpiochip_post_event(struct rtdm_gpio_chip *rgc,
 int rtdm_gpiochip_find(struct device_node *from,
 			  const char *label, int type);
 
+int rtdm_gpiochip_array_find(struct device_node *from,
+				const char *compat[],
+				int nentries, int type);
+
 #ifdef CONFIG_OF
 
 int rtdm_gpiochip_scan_of(struct device_node *from,
diff --git a/kernel/drivers/gpio/gpio-core.c b/kernel/drivers/gpio/gpio-core.c
index b3d801fa1..20a6d7875 100644
--- a/kernel/drivers/gpio/gpio-core.c
+++ b/kernel/drivers/gpio/gpio-core.c
@@ -543,6 +543,25 @@ int rtdm_gpiochip_find(struct device_node *from, const char *label,
 }
 EXPORT_SYMBOL_GPL(rtdm_gpiochip_find);
 
+int rtdm_gpiochip_array_find(struct device_node *from,
+				const char *compat[],
+				int nentries, int type)
+{
+	int ret = -ENODEV, _ret, n;
+
+	for (n = 0; n < nentries; n++) {
+		_ret = rtdm_gpiochip_find(from, compat[n], type);
+		if (_ret) {
+			if (_ret != -ENODEV)
+				return _ret;
+		} else
+			ret = 0;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rtdm_gpiochip_array_find);
+
 #ifdef CONFIG_OF
 
 #include <linux/of_platform.h>
-- 
2.17.1