drivers/net/phy/mscc.c

/*
 * Driver for Microsemi VSC85xx PHYs
 *
 * Author: Nagaraju Lakkaraju
 * License: Dual MIT/GPL
 * Copyright (c) 2016 Microsemi Corporation
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mdio.h>
#include <linux/mii.h>
#include <linux/phy.h>

enum rgmii_rx_clock_delay {
       RGMII_RX_CLK_DELAY_0_2_NS = 0,
       RGMII_RX_CLK_DELAY_0_8_NS = 1,
       RGMII_RX_CLK_DELAY_1_1_NS = 2,
       RGMII_RX_CLK_DELAY_1_7_NS = 3,
       RGMII_RX_CLK_DELAY_2_0_NS = 4,
       RGMII_RX_CLK_DELAY_2_3_NS = 5,
       RGMII_RX_CLK_DELAY_2_6_NS = 6,
       RGMII_RX_CLK_DELAY_3_4_NS = 7
};

#define MII_VSC85XX_INT_MASK              25
#define MII_VSC85XX_INT_MASK_MASK         0xa000
#define MII_VSC85XX_INT_STATUS            26

#define MSCC_EXT_PAGE_ACCESS              31
#define MSCC_PHY_PAGE_STANDARD            0x0000 /* Standard registers */
#define MSCC_PHY_PAGE_EXTENDED_2          0x0002 /* Extended reg - page 2 */

/* Extended Page 2 Registers */
#define MSCC_PHY_RGMII_CNTL                       20
#define RGMII_RX_CLK_DELAY_MASK                   0x0070
#define RGMII_RX_CLK_DELAY_POS            4

/* Microsemi PHY ID's */
#define PHY_ID_VSC8531                            0x00070570
#define PHY_ID_VSC8541                            0x00070770

static int vsc85xx_phy_page_set(struct phy_device *phydev, u8 page)
{
       int rc;

       rc = phy_write(phydev, MSCC_EXT_PAGE_ACCESS, page);
       return rc;
}

static int vsc85xx_default_config(struct phy_device *phydev)
{
       int rc;
       u16 reg_val;

       mutex_lock(&phydev->lock);
       rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED_2);
       if (rc != 0)
               goto out_unlock;

       reg_val = phy_read(phydev, MSCC_PHY_RGMII_CNTL);
       reg_val &= ~(RGMII_RX_CLK_DELAY_MASK);
       reg_val |= (RGMII_RX_CLK_DELAY_1_1_NS << RGMII_RX_CLK_DELAY_POS);
       phy_write(phydev, MSCC_PHY_RGMII_CNTL, reg_val);
       rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD);

out_unlock:
       mutex_unlock(&phydev->lock);

       return rc;
}

static int vsc85xx_config_init(struct phy_device *phydev)
{
       int rc;

       rc = vsc85xx_default_config(phydev);
       if (rc)
               return rc;
       rc = genphy_config_init(phydev);

       return rc;
}

static int vsc85xx_ack_interrupt(struct phy_device *phydev)
{
       int rc = 0;

       if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
               rc = phy_read(phydev, MII_VSC85XX_INT_STATUS);

       return (rc < 0) ? rc : 0;
}

static int vsc85xx_config_intr(struct phy_device *phydev)
{
       int rc;

       if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
               rc = phy_write(phydev, MII_VSC85XX_INT_MASK,
                                  MII_VSC85XX_INT_MASK_MASK);
       } else {
               rc = phy_write(phydev, MII_VSC85XX_INT_MASK, 0);
               if (rc < 0)
                       return rc;
               rc = phy_read(phydev, MII_VSC85XX_INT_STATUS);
       }

       return rc;
}

/* Microsemi VSC85xx PHYs */
static struct phy_driver vsc85xx_driver[] = {
{
       .phy_id                 = PHY_ID_VSC8531,
       .name                   = "Microsemi VSC8531",
       .phy_id_mask    = 0xfffffff0,
       .features               = PHY_GBIT_FEATURES,
       .flags                  = PHY_HAS_INTERRUPT,
       .soft_reset             = &genphy_soft_reset,
       .config_init    = &vsc85xx_config_init,
       .config_aneg    = &genphy_config_aneg,
       .aneg_done              = &genphy_aneg_done,
       .read_status    = &genphy_read_status,
       .ack_interrupt  = &vsc85xx_ack_interrupt,
       .config_intr    = &vsc85xx_config_intr,
       .suspend                = &genphy_suspend,
       .resume                 = &genphy_resume,
},
{
       .phy_id                 = PHY_ID_VSC8541,
       .name                   = "Microsemi VSC8541 SyncE",
       .phy_id_mask    = 0xfffffff0,
       .features               = PHY_GBIT_FEATURES,
       .flags                  = PHY_HAS_INTERRUPT,
       .soft_reset             = &genphy_soft_reset,
       .config_init    = &vsc85xx_config_init,
       .config_aneg    = &genphy_config_aneg,
       .aneg_done              = &genphy_aneg_done,
       .read_status    = &genphy_read_status,
       .ack_interrupt  = &vsc85xx_ack_interrupt,
       .config_intr    = &vsc85xx_config_intr,
       .suspend                = &genphy_suspend,
       .resume                 = &genphy_resume,
}

};

module_phy_driver(vsc85xx_driver);

static struct mdio_device_id __maybe_unused vsc85xx_tbl[] = {
       { PHY_ID_VSC8531, 0xfffffff0, },
       { PHY_ID_VSC8541, 0xfffffff0, },
       { }
};

MODULE_DEVICE_TABLE(mdio, vsc85xx_tbl);

MODULE_DESCRIPTION("Microsemi VSC85xx PHY driver");
MODULE_AUTHOR("Nagaraju Lakkaraju");
MODULE_LICENSE("Dual MIT/GPL");