[PATCH V3 2/3] drivers/gpio: core: introduce helper to find gpiochip

[hongzha1 via Xenomai]

To find gpiochip for non-OF platforms like x86

Signed-off-by: hongzha1 <hongzhan.c...@intel.com>
---
 include/cobalt/kernel/rtdm/gpio.h |  3 +++
 kernel/drivers/gpio/gpio-core.c   | 23 +++++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/cobalt/kernel/rtdm/gpio.h 
b/include/cobalt/kernel/rtdm/gpio.h
index 00055ec0a..c5fb20f25 100644
--- a/include/cobalt/kernel/rtdm/gpio.h
+++ b/include/cobalt/kernel/rtdm/gpio.h
@@ -61,6 +61,9 @@ int rtdm_gpiochip_add_by_name(struct rtdm_gpio_chip *rgc,
 int rtdm_gpiochip_post_event(struct rtdm_gpio_chip *rgc,
                             unsigned int offset);
 
+int rtdm_gpiochip_find(struct device_node *from,
+                         const char *label, 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 600ef9789..b3d801fa1 100644
--- a/kernel/drivers/gpio/gpio-core.c
+++ b/kernel/drivers/gpio/gpio-core.c
@@ -520,6 +520,29 @@ int rtdm_gpiochip_add_by_name(struct rtdm_gpio_chip *rgc,
 }
 EXPORT_SYMBOL_GPL(rtdm_gpiochip_add_by_name);
 
+int rtdm_gpiochip_find(struct device_node *from, const char *label,
+                         int type)
+{
+       struct rtdm_gpio_chip *rgc;
+       struct gpio_chip *chip;
+       int ret = -ENODEV;
+
+       if (!rtdm_available())
+               return -ENOSYS;
+
+       chip = find_chip_by_name(label);
+       if (chip == NULL)
+               return ret;
+
+       ret = 0;
+       rgc = rtdm_gpiochip_alloc(chip, type);
+       if (IS_ERR(rgc))
+               ret = PTR_ERR(rgc);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(rtdm_gpiochip_find);
+
 #ifdef CONFIG_OF
 
 #include <linux/of_platform.h>
-- 
2.17.1