[PATCH 1/3] net: phy: new ax88796b.c Asix Electronics PHY driver

[Michael Schmitz <schmitzmic@gmail.com>]

The asix.c driver name causes a module name conflict with a driver
of the same name in drivers/net/usb. Add new ax88796b.c driver to
prepare for removal of drivers/net/phy/asix.c later.

Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Fixes: 31dd83b96641 ("net-next: phy: new Asix Electronics PHY driver")
---
 drivers/net/phy/Kconfig    |  6 +++++
 drivers/net/phy/Makefile   |  1 +
 drivers/net/phy/ax88796b.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)

diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index d629971..1647473 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -259,6 +259,12 @@ config ASIX_PHY
 	  Currently supports the Asix Electronics PHY found in the X-Surf 100
 	  AX88796B package.
 
+config AX88796B_PHY
+	tristate "Asix PHYs"
+	help
+	  Currently supports the Asix Electronics PHY found in the X-Surf 100
+	  AX88796B package.
+
 config AT803X_PHY
 	tristate "AT803X PHYs"
 	---help---
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 27d7f9f..cc5758a 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -53,6 +53,7 @@ aquantia-objs			+= aquantia_hwmon.o
 endif
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia.o
 obj-$(CONFIG_ASIX_PHY)		+= asix.o
+obj-$(CONFIG_AX88796B_PHY)	+= ax88796b.o
 obj-$(CONFIG_AT803X_PHY)	+= at803x.o
 obj-$(CONFIG_BCM63XX_PHY)	+= bcm63xx.o
 obj-$(CONFIG_BCM7XXX_PHY)	+= bcm7xxx.o
diff --git a/drivers/net/phy/ax88796b.c b/drivers/net/phy/ax88796b.c
new file mode 100644
index 0000000..79bf7ef
--- /dev/null
+++ b/drivers/net/phy/ax88796b.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Driver for Asix PHYs
+ *
+ * Author: Michael Schmitz <schmitzmic@gmail.com>
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mii.h>
+#include <linux/phy.h>
+
+#define PHY_ID_ASIX_AX88796B		0x003b1841
+
+MODULE_DESCRIPTION("Asix PHY driver");
+MODULE_AUTHOR("Michael Schmitz <schmitzmic@gmail.com>");
+MODULE_LICENSE("GPL");
+
+/**
+ * asix_soft_reset - software reset the PHY via BMCR_RESET bit
+ * @phydev: target phy_device struct
+ *
+ * Description: Perform a software PHY reset using the standard
+ * BMCR_RESET bit and poll for the reset bit to be cleared.
+ * Toggle BMCR_RESET bit off to accommodate broken AX8796B PHY implementation
+ * such as used on the Individual Computers' X-Surf 100 Zorro card.
+ *
+ * Returns: 0 on success, < 0 on failure
+ */
+static int asix_soft_reset(struct phy_device *phydev)
+{
+	int ret;
+
+	/* Asix PHY won't reset unless reset bit toggles */
+	ret = phy_write(phydev, MII_BMCR, 0);
+	if (ret < 0)
+		return ret;
+
+	return genphy_soft_reset(phydev);
+}
+
+static struct phy_driver asix_driver[] = { {
+	.phy_id		= PHY_ID_ASIX_AX88796B,
+	.name		= "Asix Electronics AX88796B",
+	.phy_id_mask	= 0xfffffff0,
+	/* PHY_BASIC_FEATURES */
+	.soft_reset	= asix_soft_reset,
+} };
+
+module_phy_driver(asix_driver);
+
+static struct mdio_device_id __maybe_unused asix_tbl[] = {
+	{ PHY_ID_ASIX_AX88796B, 0xfffffff0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(mdio, asix_tbl);
-- 
1.9.1