drivers/net/phy/microchip_t1s.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Driver for Microchip 10BASE-T1S PHYs
  *
  * Support: Microchip Phys:
  *  lan8670/1/2 Rev.B1/C1
  *  lan8650/1 Rev.B0/B1 Internal PHYs
  */

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

 #define PHY_ID_LAN867X_REVB1 0x0007C162
 #define PHY_ID_LAN867X_REVC1 0x0007C164
 /* Both Rev.B0 and B1 clause 22 PHYID's are same due to B1 chip limitation */
 #define PHY_ID_LAN865X_REVB 0x0007C1B3

 #define LAN867X_REG_STS2 0x0019

 #define LAN867x_RESET_COMPLETE_STS BIT(11)

 #define LAN865X_REG_CFGPARAM_ADDR 0x00D8
 #define LAN865X_REG_CFGPARAM_DATA 0x00D9
 #define LAN865X_REG_CFGPARAM_CTRL 0x00DA
 #define LAN865X_REG_STS2 0x0019

 #define LAN865X_CFGPARAM_READ_ENABLE BIT(1)

 /* The arrays below are pulled from the following table from AN1699
  * Access MMD Address Value Mask
  * RMW 0x1F 0x00D0 0x0002 0x0E03
  * RMW 0x1F 0x00D1 0x0000 0x0300
  * RMW 0x1F 0x0084 0x3380 0xFFC0
  * RMW 0x1F 0x0085 0x0006 0x000F
  * RMW 0x1F 0x008A 0xC000 0xF800
  * RMW 0x1F 0x0087 0x801C 0x801C
  * RMW 0x1F 0x0088 0x033F 0x1FFF
  * W   0x1F 0x008B 0x0404 ------
  * RMW 0x1F 0x0080 0x0600 0x0600
  * RMW 0x1F 0x00F1 0x2400 0x7F00
  * RMW 0x1F 0x0096 0x2000 0x2000
  * W   0x1F 0x0099 0x7F80 ------
  */

 static const u32 lan867x_revb1_fixup_registers[12] = {
 	0x00D0, 0x00D1, 0x0084, 0x0085,
 	0x008A, 0x0087, 0x0088, 0x008B,
 	0x0080, 0x00F1, 0x0096, 0x0099,
 };

 static const u16 lan867x_revb1_fixup_values[12] = {
 	0x0002, 0x0000, 0x3380, 0x0006,
 	0xC000, 0x801C, 0x033F, 0x0404,
 	0x0600, 0x2400, 0x2000, 0x7F80,
 };

 static const u16 lan867x_revb1_fixup_masks[12] = {
 	0x0E03, 0x0300, 0xFFC0, 0x000F,
 	0xF800, 0x801C, 0x1FFF, 0xFFFF,
 	0x0600, 0x7F00, 0x2000, 0xFFFF,
 };

 /* LAN865x Rev.B0/B1 configuration parameters from AN1760
  * As per the Configuration Application Note AN1760 published in the below link,
  * https://www.microchip.com/en-us/application-notes/an1760
  * Revision F (DS60001760G - June 2024)
  */
 static const u32 lan865x_revb_fixup_registers[17] = {
 	0x00D0, 0x00E0, 0x00E9, 0x00F5,
 	0x00F4, 0x00F8, 0x00F9, 0x0081,
 	0x0091, 0x0043, 0x0044, 0x0045,
 	0x0053, 0x0054, 0x0055, 0x0040,
 	0x0050,
 };

 static const u16 lan865x_revb_fixup_values[17] = {
 	0x3F31, 0xC000, 0x9E50, 0x1CF8,
 	0xC020, 0xB900, 0x4E53, 0x0080,
 	0x9660, 0x00FF, 0xFFFF, 0x0000,
 	0x00FF, 0xFFFF, 0x0000, 0x0002,
 	0x0002,
 };

 static const u16 lan865x_revb_fixup_cfg_regs[2] = {
 	0x0084, 0x008A,
 };

 static const u32 lan865x_revb_sqi_fixup_regs[12] = {
 	0x00B0, 0x00B1, 0x00B2, 0x00B3,
 	0x00B4, 0x00B5, 0x00B6, 0x00B7,
 	0x00B8, 0x00B9, 0x00BA, 0x00BB,
 };

 static const u16 lan865x_revb_sqi_fixup_values[12] = {
 	0x0103, 0x0910, 0x1D26, 0x002A,
 	0x0103, 0x070D, 0x1720, 0x0027,
 	0x0509, 0x0E13, 0x1C25, 0x002B,
 };

 static const u16 lan865x_revb_sqi_fixup_cfg_regs[3] = {
 	0x00AD, 0x00AE, 0x00AF,
 };

 /* Pulled from AN1760 describing 'indirect read'
  *
  * write_register(0x4, 0x00D8, addr)
  * write_register(0x4, 0x00DA, 0x2)
  * return (int8)(read_register(0x4, 0x00D9))
  *
  * 0x4 refers to memory map selector 4, which maps to MDIO_MMD_VEND2
  */
 static int lan865x_revb_indirect_read(struct phy_device *phydev, u16 addr)
 {
 	int ret;

 	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_ADDR,
 			    addr);
 	if (ret)
 		return ret;

 	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_CTRL,
 			    LAN865X_CFGPARAM_READ_ENABLE);
 	if (ret)
 		return ret;

 	return phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_DATA);
 }

 /* This is pulled straight from AN1760 from 'calculation of offset 1' &
  * 'calculation of offset 2'
  */
 static int lan865x_generate_cfg_offsets(struct phy_device *phydev, s8 offsets[])
 {
 	const u16 fixup_regs[2] = {0x0004, 0x0008};
 	int ret;

 	for (int i = 0; i < ARRAY_SIZE(fixup_regs); i++) {
 		ret = lan865x_revb_indirect_read(phydev, fixup_regs[i]);
 		if (ret < 0)
 			return ret;

 		/* 5-bit signed value, sign extend */
 		ret &= GENMASK(4, 0);
 		if (ret & BIT(4))
 			offsets[i] = ret | 0xE0;
 		else
 			offsets[i] = ret;
 	}

 	return 0;
 }

 static int lan865x_read_cfg_params(struct phy_device *phydev,
 				   const u16 cfg_regs[], u16 cfg_params[],
 				   u8 count)
 {
 	int ret;

 	for (int i = 0; i < count; i++) {
 		ret = phy_read_mmd(phydev, MDIO_MMD_VEND2,
 				   cfg_regs[i]);
 		if (ret < 0)
 			return ret;
 		cfg_params[i] = (u16)ret;
 	}

 	return 0;
 }

 static int lan865x_write_cfg_params(struct phy_device *phydev,
 				    const u16 cfg_regs[], u16 cfg_params[],
 				    u8 count)
 {
 	int ret;

 	for (int i = 0; i < count; i++) {
 		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, cfg_regs[i],
 				    cfg_params[i]);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int lan865x_setup_cfgparam(struct phy_device *phydev, s8 offsets[])
 {
 	u16 cfg_results[ARRAY_SIZE(lan865x_revb_fixup_cfg_regs)];
 	u16 cfg_params[ARRAY_SIZE(lan865x_revb_fixup_cfg_regs)];
 	int ret;

 	ret = lan865x_read_cfg_params(phydev, lan865x_revb_fixup_cfg_regs,
 				      cfg_params, ARRAY_SIZE(cfg_params));
 	if (ret)
 		return ret;

 	cfg_results[0] = FIELD_PREP(GENMASK(15, 10), 9 + offsets[0]) |
 			 FIELD_PREP(GENMASK(9, 4), 14 + offsets[0]) |
 			 0x03;
 	cfg_results[1] = FIELD_PREP(GENMASK(15, 10), 40 + offsets[1]);

 	return lan865x_write_cfg_params(phydev, lan865x_revb_fixup_cfg_regs,
 					cfg_results, ARRAY_SIZE(cfg_results));
 }

 static int lan865x_setup_sqi_cfgparam(struct phy_device *phydev, s8 offsets[])
 {
 	u16 cfg_results[ARRAY_SIZE(lan865x_revb_sqi_fixup_cfg_regs)];
 	u16 cfg_params[ARRAY_SIZE(lan865x_revb_sqi_fixup_cfg_regs)];
 	int ret;

 	ret = lan865x_read_cfg_params(phydev, lan865x_revb_sqi_fixup_cfg_regs,
 				      cfg_params, ARRAY_SIZE(cfg_params));
 	if (ret)
 		return ret;

 	cfg_results[0] = FIELD_PREP(GENMASK(13, 8), 5 + offsets[0]) |
 			 (9 + offsets[0]);
 	cfg_results[1] = FIELD_PREP(GENMASK(13, 8), 9 + offsets[0]) |
 			 (14 + offsets[0]);
 	cfg_results[2] = FIELD_PREP(GENMASK(13, 8), 17 + offsets[0]) |
 			 (22 + offsets[0]);

 	return lan865x_write_cfg_params(phydev, lan865x_revb_sqi_fixup_cfg_regs,
 					cfg_results, ARRAY_SIZE(cfg_results));
 }

 static int lan865x_revb_config_init(struct phy_device *phydev)
 {
 	s8 offsets[2];
 	int ret;

 	/* Reference to AN1760
 	 * https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8650-1-Configuration-60001760.pdf
 	 */
 	ret = lan865x_generate_cfg_offsets(phydev, offsets);
 	if (ret)
 		return ret;

 	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_fixup_registers); i++) {
 		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
 				    lan865x_revb_fixup_registers[i],
 				    lan865x_revb_fixup_values[i]);
 		if (ret)
 			return ret;

 		if (i == 1) {
 			ret = lan865x_setup_cfgparam(phydev, offsets);
 			if (ret)
 				return ret;
 		}
 	}

 	ret = lan865x_setup_sqi_cfgparam(phydev, offsets);
 	if (ret)
 		return ret;

 	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_sqi_fixup_regs); i++) {
 		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
 				    lan865x_revb_sqi_fixup_regs[i],
 				    lan865x_revb_sqi_fixup_values[i]);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int lan867x_check_reset_complete(struct phy_device *phydev)
 {
 	int err;

 	/* The chip completes a reset in 3us, we might get here earlier than
 	 * that, as an added margin we'll conditionally sleep 5us.
 	 */
 	err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
 	if (err < 0)
 		return err;

 	if (!(err & LAN867x_RESET_COMPLETE_STS)) {
 		udelay(5);
 		err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
 		if (err < 0)
 			return err;
 		if (!(err & LAN867x_RESET_COMPLETE_STS)) {
 			phydev_err(phydev, "PHY reset failed\n");
 			return -ENODEV;
 		}
 	}

 	return 0;
 }

 static int lan867x_revc1_config_init(struct phy_device *phydev)
 {
 	s8 offsets[2];
 	int ret;

 	ret = lan867x_check_reset_complete(phydev);
 	if (ret)
 		return ret;

 	ret = lan865x_generate_cfg_offsets(phydev, offsets);
 	if (ret)
 		return ret;

 	/* LAN867x Rev.C1 configuration settings are equal to the first 9
 	 * configuration settings and all the sqi fixup settings from LAN865x
 	 * Rev.B0/B1. So the same fixup registers and values from LAN865x
 	 * Rev.B0/B1 are used for LAN867x Rev.C1 to avoid duplication.
 	 * Refer the below links for the comparison.
 	 * https://www.microchip.com/en-us/application-notes/an1760
 	 * Revision F (DS60001760G - June 2024)
 	 * https://www.microchip.com/en-us/application-notes/an1699
 	 * Revision E (DS60001699F - June 2024)
 	 */
 	for (int i = 0; i < 9; i++) {
 		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
 				    lan865x_revb_fixup_registers[i],
 				    lan865x_revb_fixup_values[i]);
 		if (ret)
 			return ret;

 		if (i == 1) {
 			ret = lan865x_setup_cfgparam(phydev, offsets);
 			if (ret)
 				return ret;
 		}
 	}

 	ret = lan865x_setup_sqi_cfgparam(phydev, offsets);
 	if (ret)
 		return ret;

 	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_sqi_fixup_regs); i++) {
 		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
 				    lan865x_revb_sqi_fixup_regs[i],
 				    lan865x_revb_sqi_fixup_values[i]);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int lan867x_revb1_config_init(struct phy_device *phydev)
 {
 	int err;

 	err = lan867x_check_reset_complete(phydev);
 	if (err)
 		return err;

 	/* Reference to AN1699
 	 * https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8670-1-2-config-60001699.pdf
 	 * AN1699 says Read, Modify, Write, but the Write is not required if the
 	 * register already has the required value. So it is safe to use
 	 * phy_modify_mmd here.
 	 */
 	for (int i = 0; i < ARRAY_SIZE(lan867x_revb1_fixup_registers); i++) {
 		err = phy_modify_mmd(phydev, MDIO_MMD_VEND2,
 				     lan867x_revb1_fixup_registers[i],
 				     lan867x_revb1_fixup_masks[i],
 				     lan867x_revb1_fixup_values[i]);
 		if (err)
 			return err;
 	}

 	return 0;
 }

 static int lan86xx_read_status(struct phy_device *phydev)
 {
 	/* The phy has some limitations, namely:
 	 *  - always reports link up
 	 *  - only supports 10MBit half duplex
 	 *  - does not support auto negotiate
 	 */
 	phydev->link = 1;
 	phydev->duplex = DUPLEX_HALF;
 	phydev->speed = SPEED_10;
 	phydev->autoneg = AUTONEG_DISABLE;

 	return 0;
 }

 /* OPEN Alliance 10BASE-T1x compliance MAC-PHYs will have both C22 and
  * C45 registers space. If the PHY is discovered via C22 bus protocol it assumes
  * it uses C22 protocol and always uses C22 registers indirect access to access
  * C45 registers. This is because, we don't have a clean separation between
  * C22/C45 register space and C22/C45 MDIO bus protocols. Resulting, PHY C45
  * registers direct access can't be used which can save multiple SPI bus access.
  * To support this feature, set .read_mmd/.write_mmd in the PHY driver to call
  * .read_c45/.write_c45 in the OPEN Alliance framework
  * drivers/net/ethernet/oa_tc6.c
  */
 static int lan865x_phy_read_mmd(struct phy_device *phydev, int devnum,
 				u16 regnum)
 {
 	struct mii_bus *bus = phydev->mdio.bus;
 	int addr = phydev->mdio.addr;

 	return __mdiobus_c45_read(bus, addr, devnum, regnum);
 }

 static int lan865x_phy_write_mmd(struct phy_device *phydev, int devnum,
 				 u16 regnum, u16 val)
 {
 	struct mii_bus *bus = phydev->mdio.bus;
 	int addr = phydev->mdio.addr;

 	return __mdiobus_c45_write(bus, addr, devnum, regnum, val);
 }

 static struct phy_driver microchip_t1s_driver[] = {
 	{
 		PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1),
 		.name               = "LAN867X Rev.B1",
 		.features           = PHY_BASIC_T1S_P2MP_FEATURES,
 		.config_init        = lan867x_revb1_config_init,
 		.read_status        = lan86xx_read_status,
 		.get_plca_cfg	    = genphy_c45_plca_get_cfg,
 		.set_plca_cfg	    = genphy_c45_plca_set_cfg,
 		.get_plca_status    = genphy_c45_plca_get_status,
 	},
 	{
 		PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVC1),
 		.name               = "LAN867X Rev.C1",
 		.features           = PHY_BASIC_T1S_P2MP_FEATURES,
 		.config_init        = lan867x_revc1_config_init,
 		.read_status        = lan86xx_read_status,
 		.get_plca_cfg	    = genphy_c45_plca_get_cfg,
 		.set_plca_cfg	    = genphy_c45_plca_set_cfg,
 		.get_plca_status    = genphy_c45_plca_get_status,
 	},
 	{
 		PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB),
 		.name               = "LAN865X Rev.B0/B1 Internal Phy",
 		.features           = PHY_BASIC_T1S_P2MP_FEATURES,
 		.config_init        = lan865x_revb_config_init,
 		.read_status        = lan86xx_read_status,
 		.read_mmd           = lan865x_phy_read_mmd,
 		.write_mmd          = lan865x_phy_write_mmd,
 		.get_plca_cfg	    = genphy_c45_plca_get_cfg,
 		.set_plca_cfg	    = genphy_c45_plca_set_cfg,
 		.get_plca_status    = genphy_c45_plca_get_status,
 	},
 };

 module_phy_driver(microchip_t1s_driver);

 static struct mdio_device_id __maybe_unused tbl[] = {
 	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1) },
 	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVC1) },
 	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB) },
 	{ }
 };

 MODULE_DEVICE_TABLE(mdio, tbl);

 MODULE_DESCRIPTION("Microchip 10BASE-T1S PHYs driver");
 MODULE_AUTHOR("Ramón Nordin Rodriguez");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Driver for Microchip 10BASE-T1S PHYs
	*
	* Support: Microchip Phys:
	* lan8670/1/2 Rev.B1/C1
	* lan8650/1 Rev.B0/B1 Internal PHYs
	*/

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

	#define PHY_ID_LAN867X_REVB1 0x0007C162
	#define PHY_ID_LAN867X_REVC1 0x0007C164
	/* Both Rev.B0 and B1 clause 22 PHYID's are same due to B1 chip limitation */
	#define PHY_ID_LAN865X_REVB 0x0007C1B3

	#define LAN867X_REG_STS2 0x0019

	#define LAN867x_RESET_COMPLETE_STS BIT(11)

	#define LAN865X_REG_CFGPARAM_ADDR 0x00D8
	#define LAN865X_REG_CFGPARAM_DATA 0x00D9
	#define LAN865X_REG_CFGPARAM_CTRL 0x00DA
	#define LAN865X_REG_STS2 0x0019

	#define LAN865X_CFGPARAM_READ_ENABLE BIT(1)

	/* The arrays below are pulled from the following table from AN1699
	* Access MMD Address Value Mask
	* RMW 0x1F 0x00D0 0x0002 0x0E03
	* RMW 0x1F 0x00D1 0x0000 0x0300
	* RMW 0x1F 0x0084 0x3380 0xFFC0
	* RMW 0x1F 0x0085 0x0006 0x000F
	* RMW 0x1F 0x008A 0xC000 0xF800
	* RMW 0x1F 0x0087 0x801C 0x801C
	* RMW 0x1F 0x0088 0x033F 0x1FFF
	* W 0x1F 0x008B 0x0404 ------
	* RMW 0x1F 0x0080 0x0600 0x0600
	* RMW 0x1F 0x00F1 0x2400 0x7F00
	* RMW 0x1F 0x0096 0x2000 0x2000
	* W 0x1F 0x0099 0x7F80 ------
	*/

	static const u32 lan867x_revb1_fixup_registers[12] = {
	0x00D0, 0x00D1, 0x0084, 0x0085,
	0x008A, 0x0087, 0x0088, 0x008B,
	0x0080, 0x00F1, 0x0096, 0x0099,
	};

	static const u16 lan867x_revb1_fixup_values[12] = {
	0x0002, 0x0000, 0x3380, 0x0006,
	0xC000, 0x801C, 0x033F, 0x0404,
	0x0600, 0x2400, 0x2000, 0x7F80,
	};

	static const u16 lan867x_revb1_fixup_masks[12] = {
	0x0E03, 0x0300, 0xFFC0, 0x000F,
	0xF800, 0x801C, 0x1FFF, 0xFFFF,
	0x0600, 0x7F00, 0x2000, 0xFFFF,
	};

	/* LAN865x Rev.B0/B1 configuration parameters from AN1760
	* As per the Configuration Application Note AN1760 published in the below link,
	* https://www.microchip.com/en-us/application-notes/an1760
	* Revision F (DS60001760G - June 2024)
	*/
	static const u32 lan865x_revb_fixup_registers[17] = {
	0x00D0, 0x00E0, 0x00E9, 0x00F5,
	0x00F4, 0x00F8, 0x00F9, 0x0081,
	0x0091, 0x0043, 0x0044, 0x0045,
	0x0053, 0x0054, 0x0055, 0x0040,
	0x0050,
	};

	static const u16 lan865x_revb_fixup_values[17] = {
	0x3F31, 0xC000, 0x9E50, 0x1CF8,
	0xC020, 0xB900, 0x4E53, 0x0080,
	0x9660, 0x00FF, 0xFFFF, 0x0000,
	0x00FF, 0xFFFF, 0x0000, 0x0002,
	0x0002,
	};

	static const u16 lan865x_revb_fixup_cfg_regs[2] = {
	0x0084, 0x008A,
	};

	static const u32 lan865x_revb_sqi_fixup_regs[12] = {
	0x00B0, 0x00B1, 0x00B2, 0x00B3,
	0x00B4, 0x00B5, 0x00B6, 0x00B7,
	0x00B8, 0x00B9, 0x00BA, 0x00BB,
	};

	static const u16 lan865x_revb_sqi_fixup_values[12] = {
	0x0103, 0x0910, 0x1D26, 0x002A,
	0x0103, 0x070D, 0x1720, 0x0027,
	0x0509, 0x0E13, 0x1C25, 0x002B,
	};

	static const u16 lan865x_revb_sqi_fixup_cfg_regs[3] = {
	0x00AD, 0x00AE, 0x00AF,
	};

	/* Pulled from AN1760 describing 'indirect read'
	*
	* write_register(0x4, 0x00D8, addr)
	* write_register(0x4, 0x00DA, 0x2)
	* return (int8)(read_register(0x4, 0x00D9))
	*
	* 0x4 refers to memory map selector 4, which maps to MDIO_MMD_VEND2
	*/
	static int lan865x_revb_indirect_read(struct phy_device *phydev, u16 addr)
	{
	int ret;

	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_ADDR,
	addr);
	if (ret)
	return ret;

	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_CTRL,
	LAN865X_CFGPARAM_READ_ENABLE);
	if (ret)
	return ret;

	return phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_DATA);
	}

	/* This is pulled straight from AN1760 from 'calculation of offset 1' &
	* 'calculation of offset 2'
	*/
	static int lan865x_generate_cfg_offsets(struct phy_device *phydev, s8 offsets[])
	{
	const u16 fixup_regs[2] = {0x0004, 0x0008};
	int ret;

	for (int i = 0; i < ARRAY_SIZE(fixup_regs); i++) {
	ret = lan865x_revb_indirect_read(phydev, fixup_regs[i]);
	if (ret < 0)
	return ret;

	/* 5-bit signed value, sign extend */
	ret &= GENMASK(4, 0);
	if (ret & BIT(4))
	offsets[i] = ret \| 0xE0;
	else
	offsets[i] = ret;
	}

	return 0;
	}

	static int lan865x_read_cfg_params(struct phy_device *phydev,
	const u16 cfg_regs[], u16 cfg_params[],
	u8 count)
	{
	int ret;

	for (int i = 0; i < count; i++) {
	ret = phy_read_mmd(phydev, MDIO_MMD_VEND2,
	cfg_regs[i]);
	if (ret < 0)
	return ret;
	cfg_params[i] = (u16)ret;
	}

	return 0;
	}

	static int lan865x_write_cfg_params(struct phy_device *phydev,
	const u16 cfg_regs[], u16 cfg_params[],
	u8 count)
	{
	int ret;

	for (int i = 0; i < count; i++) {
	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, cfg_regs[i],
	cfg_params[i]);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int lan865x_setup_cfgparam(struct phy_device *phydev, s8 offsets[])
	{
	u16 cfg_results[ARRAY_SIZE(lan865x_revb_fixup_cfg_regs)];
	u16 cfg_params[ARRAY_SIZE(lan865x_revb_fixup_cfg_regs)];
	int ret;

	ret = lan865x_read_cfg_params(phydev, lan865x_revb_fixup_cfg_regs,
	cfg_params, ARRAY_SIZE(cfg_params));
	if (ret)
	return ret;

	cfg_results[0] = FIELD_PREP(GENMASK(15, 10), 9 + offsets[0]) \|
	FIELD_PREP(GENMASK(9, 4), 14 + offsets[0]) \|
	0x03;
	cfg_results[1] = FIELD_PREP(GENMASK(15, 10), 40 + offsets[1]);

	return lan865x_write_cfg_params(phydev, lan865x_revb_fixup_cfg_regs,
	cfg_results, ARRAY_SIZE(cfg_results));
	}

	static int lan865x_setup_sqi_cfgparam(struct phy_device *phydev, s8 offsets[])
	{
	u16 cfg_results[ARRAY_SIZE(lan865x_revb_sqi_fixup_cfg_regs)];
	u16 cfg_params[ARRAY_SIZE(lan865x_revb_sqi_fixup_cfg_regs)];
	int ret;

	ret = lan865x_read_cfg_params(phydev, lan865x_revb_sqi_fixup_cfg_regs,
	cfg_params, ARRAY_SIZE(cfg_params));
	if (ret)
	return ret;

	cfg_results[0] = FIELD_PREP(GENMASK(13, 8), 5 + offsets[0]) \|
	(9 + offsets[0]);
	cfg_results[1] = FIELD_PREP(GENMASK(13, 8), 9 + offsets[0]) \|
	(14 + offsets[0]);
	cfg_results[2] = FIELD_PREP(GENMASK(13, 8), 17 + offsets[0]) \|
	(22 + offsets[0]);

	return lan865x_write_cfg_params(phydev, lan865x_revb_sqi_fixup_cfg_regs,
	cfg_results, ARRAY_SIZE(cfg_results));
	}

	static int lan865x_revb_config_init(struct phy_device *phydev)
	{
	s8 offsets[2];
	int ret;

	/* Reference to AN1760
	* https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8650-1-Configuration-60001760.pdf
	*/
	ret = lan865x_generate_cfg_offsets(phydev, offsets);
	if (ret)
	return ret;

	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_fixup_registers); i++) {
	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
	lan865x_revb_fixup_registers[i],
	lan865x_revb_fixup_values[i]);
	if (ret)
	return ret;

	if (i == 1) {
	ret = lan865x_setup_cfgparam(phydev, offsets);
	if (ret)
	return ret;
	}
	}

	ret = lan865x_setup_sqi_cfgparam(phydev, offsets);
	if (ret)
	return ret;

	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_sqi_fixup_regs); i++) {
	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
	lan865x_revb_sqi_fixup_regs[i],
	lan865x_revb_sqi_fixup_values[i]);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int lan867x_check_reset_complete(struct phy_device *phydev)
	{
	int err;

	/* The chip completes a reset in 3us, we might get here earlier than
	* that, as an added margin we'll conditionally sleep 5us.
	*/
	err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
	if (err < 0)
	return err;

	if (!(err & LAN867x_RESET_COMPLETE_STS)) {
	udelay(5);
	err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
	if (err < 0)
	return err;
	if (!(err & LAN867x_RESET_COMPLETE_STS)) {
	phydev_err(phydev, "PHY reset failed\n");
	return -ENODEV;
	}
	}

	return 0;
	}

	static int lan867x_revc1_config_init(struct phy_device *phydev)
	{
	s8 offsets[2];
	int ret;

	ret = lan867x_check_reset_complete(phydev);
	if (ret)
	return ret;

	ret = lan865x_generate_cfg_offsets(phydev, offsets);
	if (ret)
	return ret;

	/* LAN867x Rev.C1 configuration settings are equal to the first 9
	* configuration settings and all the sqi fixup settings from LAN865x
	* Rev.B0/B1. So the same fixup registers and values from LAN865x
	* Rev.B0/B1 are used for LAN867x Rev.C1 to avoid duplication.
	* Refer the below links for the comparison.
	* https://www.microchip.com/en-us/application-notes/an1760
	* Revision F (DS60001760G - June 2024)
	* https://www.microchip.com/en-us/application-notes/an1699
	* Revision E (DS60001699F - June 2024)
	*/
	for (int i = 0; i < 9; i++) {
	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
	lan865x_revb_fixup_registers[i],
	lan865x_revb_fixup_values[i]);
	if (ret)
	return ret;

	if (i == 1) {
	ret = lan865x_setup_cfgparam(phydev, offsets);
	if (ret)
	return ret;
	}
	}

	ret = lan865x_setup_sqi_cfgparam(phydev, offsets);
	if (ret)
	return ret;

	for (int i = 0; i < ARRAY_SIZE(lan865x_revb_sqi_fixup_regs); i++) {
	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
	lan865x_revb_sqi_fixup_regs[i],
	lan865x_revb_sqi_fixup_values[i]);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int lan867x_revb1_config_init(struct phy_device *phydev)
	{
	int err;

	err = lan867x_check_reset_complete(phydev);
	if (err)
	return err;

	/* Reference to AN1699
	* https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8670-1-2-config-60001699.pdf
	* AN1699 says Read, Modify, Write, but the Write is not required if the
	* register already has the required value. So it is safe to use
	* phy_modify_mmd here.
	*/
	for (int i = 0; i < ARRAY_SIZE(lan867x_revb1_fixup_registers); i++) {
	err = phy_modify_mmd(phydev, MDIO_MMD_VEND2,
	lan867x_revb1_fixup_registers[i],
	lan867x_revb1_fixup_masks[i],
	lan867x_revb1_fixup_values[i]);
	if (err)
	return err;
	}

	return 0;
	}

	static int lan86xx_read_status(struct phy_device *phydev)
	{
	/* The phy has some limitations, namely:
	* - always reports link up
	* - only supports 10MBit half duplex
	* - does not support auto negotiate
	*/
	phydev->link = 1;
	phydev->duplex = DUPLEX_HALF;
	phydev->speed = SPEED_10;
	phydev->autoneg = AUTONEG_DISABLE;

	return 0;
	}

	/* OPEN Alliance 10BASE-T1x compliance MAC-PHYs will have both C22 and
	* C45 registers space. If the PHY is discovered via C22 bus protocol it assumes
	* it uses C22 protocol and always uses C22 registers indirect access to access
	* C45 registers. This is because, we don't have a clean separation between
	* C22/C45 register space and C22/C45 MDIO bus protocols. Resulting, PHY C45
	* registers direct access can't be used which can save multiple SPI bus access.
	* To support this feature, set .read_mmd/.write_mmd in the PHY driver to call
	* .read_c45/.write_c45 in the OPEN Alliance framework
	* drivers/net/ethernet/oa_tc6.c
	*/
	static int lan865x_phy_read_mmd(struct phy_device *phydev, int devnum,
	u16 regnum)
	{
	struct mii_bus *bus = phydev->mdio.bus;
	int addr = phydev->mdio.addr;

	return __mdiobus_c45_read(bus, addr, devnum, regnum);
	}

	static int lan865x_phy_write_mmd(struct phy_device *phydev, int devnum,
	u16 regnum, u16 val)
	{
	struct mii_bus *bus = phydev->mdio.bus;
	int addr = phydev->mdio.addr;

	return __mdiobus_c45_write(bus, addr, devnum, regnum, val);
	}

	static struct phy_driver microchip_t1s_driver[] = {
	{
	PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1),
	.name = "LAN867X Rev.B1",
	.features = PHY_BASIC_T1S_P2MP_FEATURES,
	.config_init = lan867x_revb1_config_init,
	.read_status = lan86xx_read_status,
	.get_plca_cfg = genphy_c45_plca_get_cfg,
	.set_plca_cfg = genphy_c45_plca_set_cfg,
	.get_plca_status = genphy_c45_plca_get_status,
	},
	{
	PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVC1),
	.name = "LAN867X Rev.C1",
	.features = PHY_BASIC_T1S_P2MP_FEATURES,
	.config_init = lan867x_revc1_config_init,
	.read_status = lan86xx_read_status,
	.get_plca_cfg = genphy_c45_plca_get_cfg,
	.set_plca_cfg = genphy_c45_plca_set_cfg,
	.get_plca_status = genphy_c45_plca_get_status,
	},
	{
	PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB),
	.name = "LAN865X Rev.B0/B1 Internal Phy",
	.features = PHY_BASIC_T1S_P2MP_FEATURES,
	.config_init = lan865x_revb_config_init,
	.read_status = lan86xx_read_status,
	.read_mmd = lan865x_phy_read_mmd,
	.write_mmd = lan865x_phy_write_mmd,
	.get_plca_cfg = genphy_c45_plca_get_cfg,
	.set_plca_cfg = genphy_c45_plca_set_cfg,
	.get_plca_status = genphy_c45_plca_get_status,
	},
	};

	module_phy_driver(microchip_t1s_driver);

	static struct mdio_device_id __maybe_unused tbl[] = {
	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1) },
	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVC1) },
	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB) },
	{ }
	};

	MODULE_DEVICE_TABLE(mdio, tbl);

	MODULE_DESCRIPTION("Microchip 10BASE-T1S PHYs driver");
	MODULE_AUTHOR("Ramón Nordin Rodriguez");
	MODULE_LICENSE("GPL");