OpenCloudOS-Kernel/drivers/net/dsa/microchip/ksz9477_spi.c

178 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Microchip KSZ9477 series register access through SPI
*
* Copyright (C) 2017-2018 Microchip Technology Inc.
*/
#include <asm/unaligned.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spi/spi.h>
#include "ksz_priv.h"
#include "ksz_spi.h"
/* SPI frame opcodes */
#define KS_SPIOP_RD 3
#define KS_SPIOP_WR 2
#define SPI_ADDR_SHIFT 24
#define SPI_ADDR_MASK (BIT(SPI_ADDR_SHIFT) - 1)
#define SPI_TURNAROUND_SHIFT 5
/* Enough to read all switch port registers. */
#define SPI_TX_BUF_LEN 0x100
static int ksz9477_spi_read_reg(struct spi_device *spi, u32 reg, u8 *val,
unsigned int len)
{
u32 txbuf;
int ret;
txbuf = reg & SPI_ADDR_MASK;
txbuf |= KS_SPIOP_RD << SPI_ADDR_SHIFT;
txbuf <<= SPI_TURNAROUND_SHIFT;
txbuf = cpu_to_be32(txbuf);
ret = spi_write_then_read(spi, &txbuf, 4, val, len);
return ret;
}
static int ksz9477_spi_write_reg(struct spi_device *spi, u32 reg, u8 *val,
unsigned int len)
{
u32 *txbuf = (u32 *)val;
*txbuf = reg & SPI_ADDR_MASK;
*txbuf |= (KS_SPIOP_WR << SPI_ADDR_SHIFT);
*txbuf <<= SPI_TURNAROUND_SHIFT;
*txbuf = cpu_to_be32(*txbuf);
return spi_write(spi, txbuf, 4 + len);
}
static int ksz_spi_read(struct ksz_device *dev, u32 reg, u8 *data,
unsigned int len)
{
struct spi_device *spi = dev->priv;
return ksz9477_spi_read_reg(spi, reg, data, len);
}
static int ksz_spi_write(struct ksz_device *dev, u32 reg, void *data,
unsigned int len)
{
struct spi_device *spi = dev->priv;
if (len > SPI_TX_BUF_LEN)
len = SPI_TX_BUF_LEN;
memcpy(&dev->txbuf[4], data, len);
return ksz9477_spi_write_reg(spi, reg, dev->txbuf, len);
}
static int ksz_spi_read24(struct ksz_device *dev, u32 reg, u32 *val)
{
int ret;
*val = 0;
ret = ksz_spi_read(dev, reg, (u8 *)val, 3);
if (!ret) {
*val = be32_to_cpu(*val);
/* convert to 24bit */
*val >>= 8;
}
return ret;
}
static int ksz_spi_write24(struct ksz_device *dev, u32 reg, u32 value)
{
/* make it to big endian 24bit from MSB */
value <<= 8;
value = cpu_to_be32(value);
return ksz_spi_write(dev, reg, &value, 3);
}
static const struct ksz_io_ops ksz9477_spi_ops = {
.read8 = ksz_spi_read8,
.read16 = ksz_spi_read16,
.read24 = ksz_spi_read24,
.read32 = ksz_spi_read32,
.write8 = ksz_spi_write8,
.write16 = ksz_spi_write16,
.write24 = ksz_spi_write24,
.write32 = ksz_spi_write32,
.get = ksz_spi_get,
.set = ksz_spi_set,
};
static int ksz9477_spi_probe(struct spi_device *spi)
{
struct ksz_device *dev;
int ret;
dev = ksz_switch_alloc(&spi->dev, &ksz9477_spi_ops, spi);
if (!dev)
return -ENOMEM;
if (spi->dev.platform_data)
dev->pdata = spi->dev.platform_data;
dev->txbuf = devm_kzalloc(dev->dev, 4 + SPI_TX_BUF_LEN, GFP_KERNEL);
ret = ksz9477_switch_register(dev);
/* Main DSA driver may not be started yet. */
if (ret)
return ret;
spi_set_drvdata(spi, dev);
return 0;
}
static int ksz9477_spi_remove(struct spi_device *spi)
{
struct ksz_device *dev = spi_get_drvdata(spi);
if (dev)
ksz_switch_remove(dev);
return 0;
}
static void ksz9477_spi_shutdown(struct spi_device *spi)
{
struct ksz_device *dev = spi_get_drvdata(spi);
if (dev && dev->dev_ops->shutdown)
dev->dev_ops->shutdown(dev);
}
static const struct of_device_id ksz9477_dt_ids[] = {
{ .compatible = "microchip,ksz9477" },
{ .compatible = "microchip,ksz9897" },
{},
};
MODULE_DEVICE_TABLE(of, ksz9477_dt_ids);
static struct spi_driver ksz9477_spi_driver = {
.driver = {
.name = "ksz9477-switch",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(ksz9477_dt_ids),
},
.probe = ksz9477_spi_probe,
.remove = ksz9477_spi_remove,
.shutdown = ksz9477_spi_shutdown,
};
module_spi_driver(ksz9477_spi_driver);
MODULE_AUTHOR("Woojung Huh <Woojung.Huh@microchip.com>");
MODULE_DESCRIPTION("Microchip KSZ9477 Series Switch SPI access Driver");
MODULE_LICENSE("GPL");