[U-Boot] [PATCH] pinctrl: move dm_scan_fdt_node() out of pinctrl uclass

[Masahiro Yamada]

Commit c5acf4a2b3c6 ("pinctrl: Add the concept of peripheral IDs")
added some additional change that was not mentioned in the git-log.

That commit added dm_scan_fdt_node() in the pinctrl uclass binding.
It should be handled by the simple-bus driver, and it is totally
unrelated to pinctrl in the first place.

I guess Simon's motivation was to bind GPIO banks located under the
Rockchip pinctrl device.  It is true some chips have sub-devices
under their pinctrl devices, but it is basically SoC-specific matter.

Keep only pinctrl-generic features in the uclass and move others
to each low-level driver.

By the way, this strategy produces code duplication between low-level
drivers and the simple-bus driver.  Theoretically, it is possible to
have multiple compatible strings like this:

     compatible = "rockchip,rk3288-pinctrl", "simple-bus";

Actually, some device trees do this and Linux can handle it properly,
but for now U-Boot cannot.  In the current implementation of U-boot,
only the best match ("rockchip,rk3288-pinctrl" in this case) is picked
and the others are ignored.

Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
---

 drivers/pinctrl/pinctrl-uclass.c          | 15 +++++++++------
 drivers/pinctrl/rockchip/pinctrl_rk3288.c |  8 ++++++++
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-uclass.c b/drivers/pinctrl/pinctrl-uclass.c
index 58001ef..b5fdcd1 100644
--- a/drivers/pinctrl/pinctrl-uclass.c
+++ b/drivers/pinctrl/pinctrl-uclass.c
@@ -11,7 +11,6 @@
 #include <dm/device.h>
 #include <dm/lists.h>
 #include <dm/pinctrl.h>
-#include <dm/root.h>
 #include <dm/uclass.h>
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -160,8 +159,7 @@ static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
 
 static int pinconfig_post_bind(struct udevice *dev)
 {
-	/* Scan the bus for devices */
-	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+	return 0;
 }
 #endif
 
@@ -249,10 +247,15 @@ static int pinctrl_post_bind(struct udevice *dev)
 	}
 
 	/*
-	 * The pinctrl driver child nodes should be bound so that peripheral
-	 * devices can easily search in parent devices during later DT-parsing.
+	 * If set_state callback is set, we assume this pinctrl driver is the
+	 * full implementation.  In this case, its child nodes should be bound
+	 * so that peripheral devices can easily search in parent devices
+	 * during later DT-parsing.
 	 */
-	return pinconfig_post_bind(dev);
+	if (ops->set_state)
+		return pinconfig_post_bind(dev);
+
+	return 0;
 }
 
 UCLASS_DRIVER(pinctrl) = {
diff --git a/drivers/pinctrl/rockchip/pinctrl_rk3288.c b/drivers/pinctrl/rockchip/pinctrl_rk3288.c
index 5205498..c432a00 100644
--- a/drivers/pinctrl/rockchip/pinctrl_rk3288.c
+++ b/drivers/pinctrl/rockchip/pinctrl_rk3288.c
@@ -17,6 +17,7 @@
 #include <asm/arch/periph.h>
 #include <asm/arch/pmu_rk3288.h>
 #include <dm/pinctrl.h>
+#include <dm/root.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -415,6 +416,12 @@ static struct pinctrl_ops rk3288_pinctrl_ops = {
 	.get_periph_id	= rk3288_pinctrl_get_periph_id,
 };
 
+static int rk3288_pinctrl_bind(struct udevice *dev)
+{
+	/* scan child GPIO banks */
+	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
 static int rk3288_pinctrl_probe(struct udevice *dev)
 {
 	struct rk3288_pinctrl_priv *priv = dev_get_priv(dev);
@@ -437,5 +444,6 @@ U_BOOT_DRIVER(pinctrl_rk3288) = {
 	.of_match	= rk3288_pinctrl_ids,
 	.priv_auto_alloc_size = sizeof(struct rk3288_pinctrl_priv),
 	.ops		= &rk3288_pinctrl_ops,
+	.bind		= rk3288_pinctrl_bind,
 	.probe		= rk3288_pinctrl_probe,
 };
-- 
1.9.1