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 mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0xa400 | (dev << 5) | reg); 38 39 err = usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), 40 mvusb->buf, 6, &alen, 100); 41 if (err) 42 return err; 43 44 err = usb_bulk_msg(mvusb->udev, usb_rcvbulkpipe(mvusb->udev, 6), 45 &mvusb->buf[MVUSB_CMD_VAL], 2, &alen, 100); 46 if (err) 47 return err; 48 49 return le16_to_cpu(mvusb->buf[MVUSB_CMD_VAL]); 50 } 51 52 static int mvusb_mdio_write(struct mii_bus *mdio, int dev, int reg, u16 val) 53 { 54 struct mvusb_mdio *mvusb = mdio->priv; 55 int alen; 56 57 mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0x8000 | (dev << 5) | reg); 58 mvusb->buf[MVUSB_CMD_VAL] = cpu_to_le16(val); 59 60 return usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), 61 mvusb->buf, 8, &alen, 100); 62 } 63 64 static int mvusb_mdio_probe(struct usb_interface *interface, 65 const struct usb_device_id *id) 66 { 67 struct device *dev = &interface->dev; 68 struct mvusb_mdio *mvusb; 69 struct mii_bus *mdio; 70 int ret; 71 72 mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); 73 if (!mdio) 74 return -ENOMEM; 75 76 mvusb = mdio->priv; 77 mvusb->mdio = mdio; 78 mvusb->udev = usb_get_dev(interface_to_usbdev(interface)); 79 80 /* Reversed from USB PCAPs, no idea what these mean. */ 81 mvusb->buf[MVUSB_CMD_PREAMBLE0] = cpu_to_le16(0xe800); 82 mvusb->buf[MVUSB_CMD_PREAMBLE1] = cpu_to_le16(0x0001); 83 84 snprintf(mdio->id, MII_BUS_ID_SIZE, "mvusb-%s", dev_name(dev)); 85 mdio->name = mdio->id; 86 mdio->parent = dev; 87 mdio->read = mvusb_mdio_read; 88 mdio->write = mvusb_mdio_write; 89 90 usb_set_intfdata(interface, mvusb); 91 ret = of_mdiobus_register(mdio, dev->of_node); 92 if (ret) 93 goto put_dev; 94 95 return 0; 96 97 put_dev: 98 usb_put_dev(mvusb->udev); 99 return ret; 100 } 101 102 static void mvusb_mdio_disconnect(struct usb_interface *interface) 103 { 104 struct mvusb_mdio *mvusb = usb_get_intfdata(interface); 105 struct usb_device *udev = mvusb->udev; 106 107 mdiobus_unregister(mvusb->mdio); 108 usb_set_intfdata(interface, NULL); 109 usb_put_dev(udev); 110 } 111 112 static struct usb_driver mvusb_mdio_driver = { 113 .name = "mvusb_mdio", 114 .id_table = mvusb_mdio_table, 115 .probe = mvusb_mdio_probe, 116 .disconnect = mvusb_mdio_disconnect, 117 }; 118 119 module_usb_driver(mvusb_mdio_driver); 120 121 MODULE_AUTHOR("Tobias Waldekranz <tobias@waldekranz.com>"); 122 MODULE_DESCRIPTION("Marvell USB MDIO Adapter"); 123 MODULE_LICENSE("GPL"); 124