[PATCH v3] net: phy: Factor out PHY GPIO reset code

[Marek Vasut]

Pull the PHY GPIO reset code into separate function, since
this is and will be reused multiple times. Set up default
reset assert and deassert timing to generous 20ms and 1ms
for maximum compatibility in case those DT properties are
missing.

Reviewed-by: Ramon Fried <rfried.dev at gmail.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
Cc: Joe Hershberger <joe.hershberger at ni.com>
Cc: Marek Vasut <marek.vasut+renesas at mailbox.org>
Cc: Michal Simek <michal.simek at amd.com>
Cc: Nishanth Menon <nm at ti.com>
Cc: Ramon Fried <rfried.dev at gmail.com>
---
V2: - Fix am335x_evm build with OF_REAL disabled
    - Collect RB from Ramon
V3: - Drop stale conditional
---
 drivers/net/phy/ethernet_id.c | 37 ++++-------------------
 drivers/net/phy/phy.c         | 55 +++++++++++++++++++++++++++++++++++
 include/phy.h                 |  9 ++++++
 3 files changed, 69 insertions(+), 32 deletions(-)

diff --git a/drivers/net/phy/ethernet_id.c b/drivers/net/phy/ethernet_id.c
index 6cb1fd4453e..4dfdee60dcc 100644
--- a/drivers/net/phy/ethernet_id.c
+++ b/drivers/net/phy/ethernet_id.c
@@ -18,12 +18,11 @@ struct phy_device *phy_connect_phy_id(struct mii_dev *bus, struct udevice *dev,
 {
 	struct phy_device *phydev;
 	struct ofnode_phandle_args phandle_args;
-	struct gpio_desc gpio;
 	const char *node_name;
 	struct udevice *pdev;
-	ofnode node;
-	u32 id, assert, deassert;
 	u16 vendor, device;
+	ofnode node;
+	u32 id;
 	int ret;
 
 	if (dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
@@ -41,35 +40,9 @@ struct phy_device *phy_connect_phy_id(struct mii_dev *bus, struct udevice *dev,
 		return NULL;
 	}
 
-	if (!IS_ENABLED(CONFIG_DM_ETH_PHY)) {
-		ret = gpio_request_by_name_nodev(node, "reset-gpios", 0, &gpio,
-						 GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
-		if (!ret) {
-			assert = ofnode_read_u32_default(node,
-							 "reset-assert-us", 0);
-			deassert = ofnode_read_u32_default(node,
-							   "reset-deassert-us",
-							   0);
-			ret = dm_gpio_set_value(&gpio, 1);
-			if (ret) {
-				dev_err(dev,
-					"Failed assert gpio, err: %d\n", ret);
-				return NULL;
-			}
-
-			udelay(assert);
-
-			ret = dm_gpio_set_value(&gpio, 0);
-			if (ret) {
-				dev_err(dev,
-					"Failed deassert gpio, err: %d\n",
-					ret);
-				return NULL;
-			}
-
-			udelay(deassert);
-		}
-	}
+	ret = phy_gpio_reset(dev);
+	if (ret)
+		return NULL;
 
 	if (phyaddr == -1)
 		phyaddr = ofnode_read_u32_default(phandle_args.node, "reg", -1);
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 63b3e46f101..a7a6fa66268 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -18,6 +18,8 @@
 #include <phy.h>
 #include <errno.h>
 #include <asm/global_data.h>
+#include <asm-generic/gpio.h>
+#include <dm/device_compat.h>
 #include <dm/of_extra.h>
 #include <linux/bitops.h>
 #include <linux/delay.h>
@@ -768,6 +770,59 @@ int miiphy_reset(const char *devname, unsigned char addr)
 	return phy_reset(phydev);
 }
 
+#if CONFIG_IS_ENABLED(DM_GPIO) && CONFIG_IS_ENABLED(OF_REAL) && \
+    !IS_ENABLED(CONFIG_DM_ETH_PHY)
+int phy_gpio_reset(struct udevice *dev)
+{
+	struct ofnode_phandle_args phandle_args;
+	struct gpio_desc gpio;
+	u32 assert, deassert;
+	ofnode node;
+	int ret;
+
+	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
+					 &phandle_args);
+	/* No PHY handle is OK */
+	if (ret)
+		return 0;
+
+	node = phandle_args.node;
+	if (!ofnode_valid(node))
+		return -EINVAL;
+
+	ret = gpio_request_by_name_nodev(node, "reset-gpios", 0, &gpio,
+					 GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
+	/* No PHY reset GPIO is OK */
+	if (ret)
+		return 0;
+
+	assert = ofnode_read_u32_default(node, "reset-assert-us", 20000);
+	deassert = ofnode_read_u32_default(node, "reset-deassert-us", 1000);
+	ret = dm_gpio_set_value(&gpio, 1);
+	if (ret) {
+		dev_err(dev, "Failed assert gpio, err: %d\n", ret);
+		return ret;
+	}
+
+	udelay(assert);
+
+	ret = dm_gpio_set_value(&gpio, 0);
+	if (ret) {
+		dev_err(dev, "Failed deassert gpio, err: %d\n", ret);
+		return ret;
+	}
+
+	udelay(deassert);
+
+	return 0;
+}
+#else
+int phy_gpio_reset(struct udevice *dev)
+{
+	return 0;
+}
+#endif
+
 struct phy_device *phy_find_by_mask(struct mii_dev *bus, uint phy_mask)
 {
 	/* Reset the bus */
diff --git a/include/phy.h b/include/phy.h
index ae23814bbf3..90b7e364101 100644
--- a/include/phy.h
+++ b/include/phy.h
@@ -183,6 +183,15 @@ struct fixed_link {
  */
 int phy_reset(struct phy_device *phydev);
 
+/**
+ * phy_gpio_reset() - Resets the specified PHY using GPIO reset
+ * Toggles the optional PHY reset GPIO
+ *
+ * @dev:	PHY udevice to reset
+ * @return: 0 if OK, -ve on error
+ */
+int phy_gpio_reset(struct udevice *dev);
+
 /**
  * phy_find_by_mask() - Searches for a PHY on the specified MDIO bus
  * The function checks the PHY addresses flagged in phy_mask and returns a
-- 
2.43.0