drivers/net/dsa/microchip/ksz_spi.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Microchip ksz series register access through SPI
 *
 * Copyright (C) 2017-2024 Microchip Technology Inc.
 *	Tristram Ha <Tristram.Ha@microchip.com>
 */

#include <linux/unaligned.h>

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>

#include "ksz_common.h"

#define KSZ8463_SPI_ADDR_SHIFT			13
#define KSZ8463_SPI_ADDR_ALIGN			3
#define KSZ8463_SPI_TURNAROUND_SHIFT		2

#define KSZ8795_SPI_ADDR_SHIFT			12
#define KSZ8795_SPI_ADDR_ALIGN			3
#define KSZ8795_SPI_TURNAROUND_SHIFT		1

#define KSZ8863_SPI_ADDR_SHIFT			8
#define KSZ8863_SPI_ADDR_ALIGN			8
#define KSZ8863_SPI_TURNAROUND_SHIFT		0

#define KSZ9477_SPI_ADDR_SHIFT			24
#define KSZ9477_SPI_ADDR_ALIGN			3
#define KSZ9477_SPI_TURNAROUND_SHIFT		5

KSZ_REGMAP_TABLE(ksz8795, 16, KSZ8795_SPI_ADDR_SHIFT,
		 KSZ8795_SPI_TURNAROUND_SHIFT, KSZ8795_SPI_ADDR_ALIGN);

KSZ_REGMAP_TABLE(ksz8863, 16, KSZ8863_SPI_ADDR_SHIFT,
		 KSZ8863_SPI_TURNAROUND_SHIFT, KSZ8863_SPI_ADDR_ALIGN);

KSZ_REGMAP_TABLE(ksz9477, 32, KSZ9477_SPI_ADDR_SHIFT,
		 KSZ9477_SPI_TURNAROUND_SHIFT, KSZ9477_SPI_ADDR_ALIGN);

static u16 ksz8463_reg(u16 reg, size_t size)
{
	switch (size) {
	case 1:
		reg = ((reg >> 2) << 4) | (1 << (reg & 3));
		break;
	case 2:
		reg = ((reg >> 2) << 4) | (reg & 2 ? 0x0c : 0x03);
		break;
	default:
		reg = ((reg >> 2) << 4) | 0xf;
		break;
	}
	reg <<= KSZ8463_SPI_TURNAROUND_SHIFT;
	return reg;
}

static int ksz8463_spi_read(void *context,
			    const void *reg, size_t reg_size,
			    void *val, size_t val_size)
{
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);
	u8 bytes[2];
	u16 cmd;
	int rc;

	if (reg_size > 2 || val_size > 4)
		return -EINVAL;
	memcpy(&cmd, reg, sizeof(u16));
	cmd = ksz8463_reg(cmd, val_size);
	/* SPI command uses big-endian format. */
	put_unaligned_be16(cmd, bytes);
	rc = spi_write_then_read(spi, bytes, reg_size, val, val_size);
#if defined(__BIG_ENDIAN)
	/* Register value uses little-endian format so need to convert when
	 * running in big-endian system.
	 */
	if (!rc && val_size > 1) {
		if (val_size == 2) {
			u16 v = get_unaligned_le16(val);

			memcpy(val, &v, sizeof(v));
		} else if (val_size == 4) {
			u32 v = get_unaligned_le32(val);

			memcpy(val, &v, sizeof(v));
		}
	}
#endif
	return rc;
}

static int ksz8463_spi_write(void *context, const void *data, size_t count)
{
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);
	size_t val_size = count - 2;
	u8 bytes[6];
	u16 cmd;

	if (count <= 2 || count > 6)
		return -EINVAL;
	memcpy(bytes, data, count);
	memcpy(&cmd, data, sizeof(u16));
	cmd = ksz8463_reg(cmd, val_size);
	cmd |= (1 << (KSZ8463_SPI_ADDR_SHIFT + KSZ8463_SPI_TURNAROUND_SHIFT));
	/* SPI command uses big-endian format. */
	put_unaligned_be16(cmd, bytes);
#if defined(__BIG_ENDIAN)
	/* Register value uses little-endian format so need to convert when
	 * running in big-endian system.
	 */
	if (val_size == 2) {
		u8 *val = &bytes[2];
		u16 v;

		memcpy(&v, val, sizeof(v));
		put_unaligned_le16(v, val);
	} else if (val_size == 4) {
		u8 *val = &bytes[2];
		u32 v;

		memcpy(&v, val, sizeof(v));
		put_unaligned_le32(v, val);
	}
#endif
	return spi_write(spi, bytes, count);
}

KSZ8463_REGMAP_TABLE(ksz8463, KSZ8463_SPI_ADDR_SHIFT, 0,
		     KSZ8463_SPI_ADDR_ALIGN);

static int ksz_spi_probe(struct spi_device *spi)
{
	const struct regmap_config *regmap_config;
	const struct ksz_chip_data *chip;
	struct device *ddev = &spi->dev;
	struct regmap_config rc;
	struct ksz_device *dev;
	int i, ret = 0;

	chip = device_get_match_data(ddev);
	if (!chip)
		return -EINVAL;

	dev = ksz_switch_alloc(&spi->dev, chip, spi);
	if (!dev)
		return -ENOMEM;

	/* Save chip id to do special initialization when probing. */
	dev->chip_id = chip->chip_id;
	if (chip->chip_id == KSZ88X3_CHIP_ID)
		regmap_config = ksz8863_regmap_config;
	else if (chip->chip_id == KSZ8463_CHIP_ID)
		regmap_config = ksz8463_regmap_config;
	else if (chip->chip_id == KSZ8795_CHIP_ID ||
		 chip->chip_id == KSZ8794_CHIP_ID ||
		 chip->chip_id == KSZ8765_CHIP_ID)
		regmap_config = ksz8795_regmap_config;
	else if (chip->chip_id == KSZ8895_CHIP_ID ||
		 chip->chip_id == KSZ8864_CHIP_ID)
		regmap_config = ksz8863_regmap_config;
	else
		regmap_config = ksz9477_regmap_config;

	for (i = 0; i < __KSZ_NUM_REGMAPS; i++) {
		rc = regmap_config[i];
		rc.lock_arg = &dev->regmap_mutex;
		rc.wr_table = chip->wr_table;
		rc.rd_table = chip->rd_table;
		dev->regmap[i] = devm_regmap_init_spi(spi, &rc);

		if (IS_ERR(dev->regmap[i])) {
			return dev_err_probe(&spi->dev, PTR_ERR(dev->regmap[i]),
					     "Failed to initialize regmap%i\n",
					     regmap_config[i].val_bits);
		}
	}

	if (spi->dev.platform_data)
		dev->pdata = spi->dev.platform_data;

	/* setup spi */
	spi->mode = SPI_MODE_3;
	ret = spi_setup(spi);
	if (ret)
		return ret;

	dev->irq = spi->irq;

	ret = ksz_switch_register(dev);

	/* Main DSA driver may not be started yet. */
	if (ret)
		return ret;

	spi_set_drvdata(spi, dev);

	return 0;
}

static void ksz_spi_remove(struct spi_device *spi)
{
	struct ksz_device *dev = spi_get_drvdata(spi);

	if (dev)
		ksz_switch_remove(dev);
}

static void ksz_spi_shutdown(struct spi_device *spi)
{
	struct ksz_device *dev = spi_get_drvdata(spi);

	if (!dev)
		return;

	ksz_switch_shutdown(dev);

	spi_set_drvdata(spi, NULL);
}

static const struct of_device_id ksz_dt_ids[] = {
	{
		.compatible = "microchip,ksz8463",
		.data = &ksz_switch_chips[KSZ8463]
	},
	{
		.compatible = "microchip,ksz8765",
		.data = &ksz_switch_chips[KSZ8765]
	},
	{
		.compatible = "microchip,ksz8794",
		.data = &ksz_switch_chips[KSZ8794]
	},
	{
		.compatible = "microchip,ksz8795",
		.data = &ksz_switch_chips[KSZ8795]
	},
	{
		.compatible = "microchip,ksz8863",
		.data = &ksz_switch_chips[KSZ88X3]
	},
	{
		.compatible = "microchip,ksz8864",
		.data = &ksz_switch_chips[KSZ8864]
	},
	{
		.compatible = "microchip,ksz8873",
		.data = &ksz_switch_chips[KSZ88X3]
	},
	{
		.compatible = "microchip,ksz8895",
		.data = &ksz_switch_chips[KSZ8895]
	},
	{
		.compatible = "microchip,ksz9477",
		.data = &ksz_switch_chips[KSZ9477]
	},
	{
		.compatible = "microchip,ksz9896",
		.data = &ksz_switch_chips[KSZ9896]
	},
	{
		.compatible = "microchip,ksz9897",
		.data = &ksz_switch_chips[KSZ9897]
	},
	{
		.compatible = "microchip,ksz9893",
		.data = &ksz_switch_chips[KSZ9893]
	},
	{
		.compatible = "microchip,ksz9563",
		.data = &ksz_switch_chips[KSZ9563]
	},
	{
		.compatible = "microchip,ksz8563",
		.data = &ksz_switch_chips[KSZ8563]
	},
	{
		.compatible = "microchip,ksz8567",
		.data = &ksz_switch_chips[KSZ8567]
	},
	{
		.compatible = "microchip,ksz9567",
		.data = &ksz_switch_chips[KSZ9567]
	},
	{
		.compatible = "microchip,lan9370",
		.data = &ksz_switch_chips[LAN9370]
	},
	{
		.compatible = "microchip,lan9371",
		.data = &ksz_switch_chips[LAN9371]
	},
	{
		.compatible = "microchip,lan9372",
		.data = &ksz_switch_chips[LAN9372]
	},
	{
		.compatible = "microchip,lan9373",
		.data = &ksz_switch_chips[LAN9373]
	},
	{
		.compatible = "microchip,lan9374",
		.data = &ksz_switch_chips[LAN9374]
	},
	{
		.compatible = "microchip,lan9646",
		.data = &ksz_switch_chips[LAN9646]
	},
	{},
};
MODULE_DEVICE_TABLE(of, ksz_dt_ids);

static const struct spi_device_id ksz_spi_ids[] = {
	{ "ksz8463" },
	{ "ksz8765" },
	{ "ksz8794" },
	{ "ksz8795" },
	{ "ksz8863" },
	{ "ksz8864" },
	{ "ksz8873" },
	{ "ksz8895" },
	{ "ksz9477" },
	{ "ksz9896" },
	{ "ksz9897" },
	{ "ksz9893" },
	{ "ksz9563" },
	{ "ksz8563" },
	{ "ksz8567" },
	{ "ksz9567" },
	{ "lan9370" },
	{ "lan9371" },
	{ "lan9372" },
	{ "lan9373" },
	{ "lan9374" },
	{ "lan9646" },
	{ },
};
MODULE_DEVICE_TABLE(spi, ksz_spi_ids);

static DEFINE_SIMPLE_DEV_PM_OPS(ksz_spi_pm_ops,
				ksz_switch_suspend, ksz_switch_resume);

static struct spi_driver ksz_spi_driver = {
	.driver = {
		.name	= "ksz-switch",
		.of_match_table = ksz_dt_ids,
		.pm = &ksz_spi_pm_ops,
	},
	.id_table = ksz_spi_ids,
	.probe	= ksz_spi_probe,
	.remove	= ksz_spi_remove,
	.shutdown = ksz_spi_shutdown,
};

module_spi_driver(ksz_spi_driver);

MODULE_ALIAS("spi:lan937x");
MODULE_AUTHOR("Tristram Ha <Tristram.Ha@microchip.com>");
MODULE_DESCRIPTION("Microchip ksz Series Switch SPI Driver");
MODULE_LICENSE("GPL");