Add "ASIX PHY Driver" page

Content provided by FUJITA Tomonori.

Signed-off-by: Miguel Ojeda <[email protected]>

Author: ojeda

SUMMARY.md

@@ -31,6 +31,7 @@
 
 ## Users — in-tree
 
+  - [ASIX PHY Driver](ASIX-PHY-Driver.md)
   - [Null Block Driver](Null-Block-Driver.md)
 
 ## Users — out-of-tree

src/ASIX-PHY-Driver.md

@@ -0,0 +1,7 @@
+# ASIX PHY Driver
+
+The Rust ASIX driver is for ASIX Electronics' Ethernet PHY (Physical Layer) devices. This driver facilitates communication between the operating system and the ASIX AX887xx chips, ensuring proper network functionality.
+
+The driver is the first Rust driver merged into the Linux kernel. It was [merged](https://git.kernel.org/linus/cbe0e415089636170aa6eb540ca4af5dc9842a60) into Linux kernel version v6.8-rc1 along with a PHY abstraction that provides safe APIs for PHY drivers.
+
+The ASIX driver is [a Rust reference driver](Rust-reference-drivers.md). It serves as a guide for developers. ASIX PHY chips are widely used in affordable 10/100M USB Ethernet adapters from various vendors.