1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Driver for Motorcomm PHYs
  4 *
  5 * Author: Peter Geis <pgwipeout@gmail.com>
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/phy.h>
 11
 12#define PHY_ID_YT8511		0x0000010a
 13
 14#define YT8511_PAGE_SELECT	0x1e
 15#define YT8511_PAGE		0x1f
 16#define YT8511_EXT_CLK_GATE	0x0c
 17#define YT8511_EXT_DELAY_DRIVE	0x0d
 18#define YT8511_EXT_SLEEP_CTRL	0x27
 19
 20/* 2b00 25m from pll
 21 * 2b01 25m from xtl *default*
 22 * 2b10 62.m from pll
 23 * 2b11 125m from pll
 24 */
 25#define YT8511_CLK_125M		(BIT(2) | BIT(1))
 26#define YT8511_PLLON_SLP	BIT(14)
 27
 28/* RX Delay enabled = 1.8ns 1000T, 8ns 10/100T */
 29#define YT8511_DELAY_RX		BIT(0)
 30
 31/* TX Gig-E Delay is bits 7:4, default 0x5
 32 * TX Fast-E Delay is bits 15:12, default 0xf
 33 * Delay = 150ps * N - 250ps
 34 * On = 2000ps, off = 50ps
 35 */
 36#define YT8511_DELAY_GE_TX_EN	(0xf << 4)
 37#define YT8511_DELAY_GE_TX_DIS	(0x2 << 4)
 38#define YT8511_DELAY_FE_TX_EN	(0xf << 12)
 39#define YT8511_DELAY_FE_TX_DIS	(0x2 << 12)
 40
 41static int yt8511_read_page(struct phy_device *phydev)
 42{
 43	return __phy_read(phydev, YT8511_PAGE_SELECT);
 44};
 45
 46static int yt8511_write_page(struct phy_device *phydev, int page)
 47{
 48	return __phy_write(phydev, YT8511_PAGE_SELECT, page);
 49};
 50
 51static int yt8511_config_init(struct phy_device *phydev)
 52{
 53	int oldpage, ret = 0;
 54	unsigned int ge, fe;
 55
 56	oldpage = phy_select_page(phydev, YT8511_EXT_CLK_GATE);
 57	if (oldpage < 0)
 58		goto err_restore_page;
 59
 60	/* set rgmii delay mode */
 61	switch (phydev->interface) {
 62	case PHY_INTERFACE_MODE_RGMII:
 63		ge = YT8511_DELAY_GE_TX_DIS;
 64		fe = YT8511_DELAY_FE_TX_DIS;
 65		break;
 66	case PHY_INTERFACE_MODE_RGMII_RXID:
 67		ge = YT8511_DELAY_RX | YT8511_DELAY_GE_TX_DIS;
 68		fe = YT8511_DELAY_FE_TX_DIS;
 69		break;
 70	case PHY_INTERFACE_MODE_RGMII_TXID:
 71		ge = YT8511_DELAY_GE_TX_EN;
 72		fe = YT8511_DELAY_FE_TX_EN;
 73		break;
 74	case PHY_INTERFACE_MODE_RGMII_ID:
 75		ge = YT8511_DELAY_RX | YT8511_DELAY_GE_TX_EN;
 76		fe = YT8511_DELAY_FE_TX_EN;
 77		break;
 78	default: /* do not support other modes */
 79		ret = -EOPNOTSUPP;
 80		goto err_restore_page;
 81	}
 82
 83	ret = __phy_modify(phydev, YT8511_PAGE, (YT8511_DELAY_RX | YT8511_DELAY_GE_TX_EN), ge);
 84	if (ret < 0)
 85		goto err_restore_page;
 86
 87	/* set clock mode to 125mhz */
 88	ret = __phy_modify(phydev, YT8511_PAGE, 0, YT8511_CLK_125M);
 89	if (ret < 0)
 90		goto err_restore_page;
 91
 92	/* fast ethernet delay is in a separate page */
 93	ret = __phy_write(phydev, YT8511_PAGE_SELECT, YT8511_EXT_DELAY_DRIVE);
 94	if (ret < 0)
 95		goto err_restore_page;
 96
 97	ret = __phy_modify(phydev, YT8511_PAGE, YT8511_DELAY_FE_TX_EN, fe);
 98	if (ret < 0)
 99		goto err_restore_page;
100
101	/* leave pll enabled in sleep */
102	ret = __phy_write(phydev, YT8511_PAGE_SELECT, YT8511_EXT_SLEEP_CTRL);
103	if (ret < 0)
104		goto err_restore_page;
105
106	ret = __phy_modify(phydev, YT8511_PAGE, 0, YT8511_PLLON_SLP);
107	if (ret < 0)
108		goto err_restore_page;
109
110err_restore_page:
111	return phy_restore_page(phydev, oldpage, ret);
112}
113
114static struct phy_driver motorcomm_phy_drvs[] = {
115	{
116		PHY_ID_MATCH_EXACT(PHY_ID_YT8511),
117		.name		= "YT8511 Gigabit Ethernet",
118		.config_init	= yt8511_config_init,
119		.suspend	= genphy_suspend,
120		.resume		= genphy_resume,
121		.read_page	= yt8511_read_page,
122		.write_page	= yt8511_write_page,
123	},
124};
125
126module_phy_driver(motorcomm_phy_drvs);
127
128MODULE_DESCRIPTION("Motorcomm PHY driver");
129MODULE_AUTHOR("Peter Geis");
130MODULE_LICENSE("GPL");
131
132static const struct mdio_device_id __maybe_unused motorcomm_tbl[] = {
133	{ PHY_ID_MATCH_EXACT(PHY_ID_YT8511) },
134	{ /* sentinal */ }
135};
136
137MODULE_DEVICE_TABLE(mdio, motorcomm_tbl);