drivers/phy/phy-bcm-ns2-pcie.c

   1 /*
   2  * Copyright (C) 2016 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation version 2.
   7  *
   8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
   9  * kind, whether express or implied; without even the implied warranty
  10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/device.h>
  15 #include <linux/module.h>
  16 #include <linux/of_mdio.h>
  17 #include <linux/mdio.h>
  18 #include <linux/phy.h>
  19 #include <linux/phy/phy.h>
  20
  21 struct ns2_pci_phy {
  22         struct mdio_device *mdiodev;
  23         struct phy *phy;
  24 };
  25
  26 #define BLK_ADDR_REG_OFFSET     0x1f
  27 #define PLL_AFE1_100MHZ_BLK     0x2100
  28 #define PLL_CLK_AMP_OFFSET      0x03
  29 #define PLL_CLK_AMP_2P05V       0x2b18
  30
  31 static int ns2_pci_phy_init(struct phy *p)
  32 {
  33         struct ns2_pci_phy *phy = phy_get_drvdata(p);
  34         int rc;
  35
  36         /* select the AFE 100MHz block page */
  37         rc = mdiobus_write(phy->mdiodev->bus, phy->mdiodev->addr,
  38                            BLK_ADDR_REG_OFFSET, PLL_AFE1_100MHZ_BLK);
  39         if (rc)
  40                 goto err;
  41
  42         /* set the 100 MHz reference clock amplitude to 2.05 v */
  43         rc = mdiobus_write(phy->mdiodev->bus, phy->mdiodev->addr,
  44                            PLL_CLK_AMP_OFFSET, PLL_CLK_AMP_2P05V);
  45         if (rc)
  46                 goto err;
  47
  48         return 0;
  49
  50 err:
  51         dev_err(&phy->mdiodev->dev, "Error %d writing to phy\n", rc);
  52         return rc;
  53 }
  54
  55 static struct phy_ops ns2_pci_phy_ops = {
  56         .init = ns2_pci_phy_init,
  57 };
  58
  59 static int ns2_pci_phy_probe(struct mdio_device *mdiodev)
  60 {
  61         struct device *dev = &mdiodev->dev;
  62         struct phy_provider *provider;
  63         struct ns2_pci_phy *p;
  64         struct phy *phy;
  65
  66         phy = devm_phy_create(dev, dev->of_node, &ns2_pci_phy_ops);
  67         if (IS_ERR(phy)) {
  68                 dev_err(dev, "failed to create Phy\n");
  69                 return PTR_ERR(phy);
  70         }
  71
  72         p = devm_kmalloc(dev, sizeof(struct ns2_pci_phy),
  73                          GFP_KERNEL);
  74         if (!p)
  75                 return -ENOMEM;
  76
  77         p->mdiodev = mdiodev;
  78         dev_set_drvdata(dev, p);
  79
  80         p->phy = phy;
  81         phy_set_drvdata(phy, p);
  82
  83         provider = devm_of_phy_provider_register(&phy->dev,
  84                                                  of_phy_simple_xlate);
  85         if (IS_ERR(provider)) {
  86                 dev_err(dev, "failed to register Phy provider\n");
  87                 return PTR_ERR(provider);
  88         }
  89
  90         dev_info(dev, "%s PHY registered\n", dev_name(dev));
  91
  92         return 0;
  93 }
  94
  95 static const struct of_device_id ns2_pci_phy_of_match[] = {
  96         { .compatible = "brcm,ns2-pcie-phy", },
  97         { /* sentinel */ },
  98 };
  99 MODULE_DEVICE_TABLE(of, ns2_pci_phy_of_match);
 100
 101 static struct mdio_driver ns2_pci_phy_driver = {
 102         .mdiodrv = {
 103                 .driver = {
 104                         .name = "phy-bcm-ns2-pci",
 105                         .of_match_table = ns2_pci_phy_of_match,
 106                 },
 107         },
 108         .probe = ns2_pci_phy_probe,
 109 };
 110 mdio_module_driver(ns2_pci_phy_driver);
 111
 112 MODULE_AUTHOR("Broadcom");
 113 MODULE_DESCRIPTION("Broadcom Northstar2 PCI Phy driver");
 114 MODULE_LICENSE("GPL v2");
 115 MODULE_ALIAS("platform:phy-bcm-ns2-pci");