1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/kernel.h> 4 #include <linux/module.h> 5 #include <linux/of_mdio.h> 6 #include <linux/phy.h> 7 #include <linux/usb.h> 8 9 #define USB_MARVELL_VID 0x1286 10 11 static const struct usb_device_id mvusb_mdio_table[] = { 12 { USB_DEVICE(USB_MARVELL_VID, 0x1fa4) }, 13 14 {} 15 }; 16 MODULE_DEVICE_TABLE(usb, mvusb_mdio_table); 17 18 enum { 19 MVUSB_CMD_PREAMBLE0, 20 MVUSB_CMD_PREAMBLE1, 21 MVUSB_CMD_ADDR, 22 MVUSB_CMD_VAL, 23 }; 24 25 struct mvusb_mdio { 26 struct usb_device *udev; 27 struct mii_bus *mdio; 28 29 __le16 buf[4]; 30 }; 31 32 static int mvusb_mdio_read(struct mii_bus *mdio, int dev, int reg) 33 { 34 struct mvusb_mdio *mvusb = mdio->priv; 35 int err, alen; 36 37 if (dev & MII_ADDR_C45) 38 return -EOPNOTSUPP; 39 40 mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0xa400 | (dev << 5) | reg); 41 42 err = usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), 43 mvusb->buf, 6, &alen, 100); 44 if (err) 45 return err; 46 47 err = usb_bulk_msg(mvusb->udev, usb_rcvbulkpipe(mvusb->udev, 6), 48 &mvusb->buf[MVUSB_CMD_VAL], 2, &alen, 100); 49 if (err) 50 return err; 51 52 return le16_to_cpu(mvusb->buf[MVUSB_CMD_VAL]); 53 } 54 55 static int mvusb_mdio_write(struct mii_bus *mdio, int dev, int reg, u16 val) 56 { 57 struct mvusb_mdio *mvusb = mdio->priv; 58 int alen; 59 60 if (dev & MII_ADDR_C45) 61 return -EOPNOTSUPP; 62 63 mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0x8000 | (dev << 5) | reg); 64 mvusb->buf[MVUSB_CMD_VAL] = cpu_to_le16(val); 65 66 return usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), 67 mvusb->buf, 8, &alen, 100); 68 } 69 70 static int mvusb_mdio_probe(struct usb_interface *interface, 71 const struct usb_device_id *id) 72 { 73 struct device *dev = &interface->dev; 74 struct mvusb_mdio *mvusb; 75 struct mii_bus *mdio; 76 77 mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); 78 if (!mdio) 79 return -ENOMEM; 80 81 mvusb = mdio->priv; 82 mvusb->mdio = mdio; 83 mvusb->udev = usb_get_dev(interface_to_usbdev(interface)); 84 85 /* Reversed from USB PCAPs, no idea what these mean. */ 86 mvusb->buf[MVUSB_CMD_PREAMBLE0] = cpu_to_le16(0xe800); 87 mvusb->buf[MVUSB_CMD_PREAMBLE1] = cpu_to_le16(0x0001); 88 89 snprintf(mdio->id, MII_BUS_ID_SIZE, "mvusb-%s", dev_name(dev)); 90 mdio->name = mdio->id; 91 mdio->parent = dev; 92 mdio->read = mvusb_mdio_read; 93 mdio->write = mvusb_mdio_write; 94 95 usb_set_intfdata(interface, mvusb); 96 return of_mdiobus_register(mdio, dev->of_node); 97 } 98 99 static void mvusb_mdio_disconnect(struct usb_interface *interface) 100 { 101 struct mvusb_mdio *mvusb = usb_get_intfdata(interface); 102 struct usb_device *udev = mvusb->udev; 103 104 mdiobus_unregister(mvusb->mdio); 105 usb_set_intfdata(interface, NULL); 106 usb_put_dev(udev); 107 } 108 109 static struct usb_driver mvusb_mdio_driver = { 110 .name = "mvusb_mdio", 111 .id_table = mvusb_mdio_table, 112 .probe = mvusb_mdio_probe, 113 .disconnect = mvusb_mdio_disconnect, 114 }; 115 116 module_usb_driver(mvusb_mdio_driver); 117 118 MODULE_AUTHOR("Tobias Waldekranz <tobias@waldekranz.com>"); 119 MODULE_DESCRIPTION("Marvell USB MDIO Adapter"); 120 MODULE_LICENSE("GPL"); 121