xref: /linux/drivers/net/phy/ax88796b_rust.rs (revision d8f87aa5fa0a4276491fa8ef436cd22605a3f9ba)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2023 FUJITA Tomonori <fujita.tomonori@gmail.com>
3 
4 //! Rust Asix PHYs driver
5 //!
6 //! C version of this driver: [`drivers/net/phy/ax88796b.c`](./ax88796b.c)
7 use kernel::{
8     net::phy::{self, reg::C22, DeviceId, Driver},
9     prelude::*,
10     uapi,
11 };
12 
13 kernel::module_phy_driver! {
14     drivers: [PhyAX88772A, PhyAX88772C, PhyAX88796B],
15     device_table: [
16         DeviceId::new_with_driver::<PhyAX88772A>(),
17         DeviceId::new_with_driver::<PhyAX88772C>(),
18         DeviceId::new_with_driver::<PhyAX88796B>()
19     ],
20     name: "rust_asix_phy",
21     authors: ["FUJITA Tomonori <fujita.tomonori@gmail.com>"],
22     description: "Rust Asix PHYs driver",
23     license: "GPL",
24 }
25 
26 const BMCR_SPEED100: u16 = uapi::BMCR_SPEED100 as u16;
27 const BMCR_FULLDPLX: u16 = uapi::BMCR_FULLDPLX as u16;
28 
29 // Performs a software PHY reset using the standard
30 // BMCR_RESET bit and poll for the reset bit to be cleared.
31 // Toggle BMCR_RESET bit off to accommodate broken AX8796B PHY implementation
32 // such as used on the Individual Computers' X-Surf 100 Zorro card.
33 fn asix_soft_reset(dev: &mut phy::Device) -> Result {
34     dev.write(C22::BMCR, 0)?;
35     dev.genphy_soft_reset()
36 }
37 
38 struct PhyAX88772A;
39 
40 #[vtable]
41 impl Driver for PhyAX88772A {
42     const FLAGS: u32 = phy::flags::IS_INTERNAL;
43     const NAME: &'static CStr = c"Asix Electronics AX88772A";
44     const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_exact_mask(0x003b1861);
45 
46     // AX88772A is not working properly with some old switches (NETGEAR EN 108TP):
47     // after autoneg is done and the link status is reported as active, the MII_LPA
48     // register is 0. This issue is not reproducible on AX88772C.
49     fn read_status(dev: &mut phy::Device) -> Result<u16> {
50         dev.genphy_update_link()?;
51         if !dev.is_link_up() {
52             return Ok(0);
53         }
54         // If MII_LPA is 0, phy_resolve_aneg_linkmode() will fail to resolve
55         // linkmode so use MII_BMCR as default values.
56         let ret = dev.read(C22::BMCR)?;
57 
58         if ret & BMCR_SPEED100 != 0 {
59             dev.set_speed(uapi::SPEED_100);
60         } else {
61             dev.set_speed(uapi::SPEED_10);
62         }
63 
64         let duplex = if ret & BMCR_FULLDPLX != 0 {
65             phy::DuplexMode::Full
66         } else {
67             phy::DuplexMode::Half
68         };
69         dev.set_duplex(duplex);
70 
71         dev.genphy_read_lpa()?;
72 
73         if dev.is_autoneg_enabled() && dev.is_autoneg_completed() {
74             dev.resolve_aneg_linkmode();
75         }
76 
77         Ok(0)
78     }
79 
80     fn suspend(dev: &mut phy::Device) -> Result {
81         dev.genphy_suspend()
82     }
83 
84     fn resume(dev: &mut phy::Device) -> Result {
85         dev.genphy_resume()
86     }
87 
88     fn soft_reset(dev: &mut phy::Device) -> Result {
89         asix_soft_reset(dev)
90     }
91 
92     fn link_change_notify(dev: &mut phy::Device) {
93         // Reset PHY, otherwise MII_LPA will provide outdated information.
94         // This issue is reproducible only with some link partner PHYs.
95         if dev.state() == phy::DeviceState::NoLink {
96             let _ = dev.init_hw();
97             let _ = dev.start_aneg();
98         }
99     }
100 }
101 
102 struct PhyAX88772C;
103 
104 #[vtable]
105 impl Driver for PhyAX88772C {
106     const FLAGS: u32 = phy::flags::IS_INTERNAL;
107     const NAME: &'static CStr = c"Asix Electronics AX88772C";
108     const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_exact_mask(0x003b1881);
109 
110     fn suspend(dev: &mut phy::Device) -> Result {
111         dev.genphy_suspend()
112     }
113 
114     fn resume(dev: &mut phy::Device) -> Result {
115         dev.genphy_resume()
116     }
117 
118     fn soft_reset(dev: &mut phy::Device) -> Result {
119         asix_soft_reset(dev)
120     }
121 }
122 
123 struct PhyAX88796B;
124 
125 #[vtable]
126 impl Driver for PhyAX88796B {
127     const NAME: &'static CStr = c"Asix Electronics AX88796B";
128     const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_model_mask(0x003b1841);
129 
130     fn soft_reset(dev: &mut phy::Device) -> Result {
131         asix_soft_reset(dev)
132     }
133 }
134