OpenWrt – Rev 4
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/*
* B53 register access through SPI
*
* Copyright (C) 2011-2013 Jonas Gorski <jogo@openwrt.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <asm/unaligned.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/of.h>
#include <linux/platform_data/b53.h>
#include "b53_priv.h"
#define B53_SPI_DATA 0xf0
#define B53_SPI_STATUS 0xfe
#define B53_SPI_CMD_SPIF BIT(7)
#define B53_SPI_CMD_RACK BIT(5)
#define B53_SPI_CMD_READ 0x00
#define B53_SPI_CMD_WRITE 0x01
#define B53_SPI_CMD_NORMAL 0x60
#define B53_SPI_CMD_FAST 0x10
#define B53_SPI_PAGE_SELECT 0xff
static inline int b53_spi_read_reg(struct spi_device *spi, u8 reg, u8 *val,
unsigned len)
{
u8 txbuf[2];
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_READ;
txbuf[1] = reg;
return spi_write_then_read(spi, txbuf, 2, val, len);
}
static inline int b53_spi_clear_status(struct spi_device *spi)
{
unsigned int i;
u8 rxbuf;
int ret;
for (i = 0; i < 10; i++) {
ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
if (ret)
return ret;
if (!(rxbuf & B53_SPI_CMD_SPIF))
break;
mdelay(1);
}
if (i == 10)
return -EIO;
return 0;
}
static inline int b53_spi_set_page(struct spi_device *spi, u8 page)
{
u8 txbuf[3];
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = B53_SPI_PAGE_SELECT;
txbuf[2] = page;
return spi_write(spi, txbuf, sizeof(txbuf));
}
static inline int b53_prepare_reg_access(struct spi_device *spi, u8 page)
{
int ret = b53_spi_clear_status(spi);
if (ret)
return ret;
return b53_spi_set_page(spi, page);
}
static int b53_spi_prepare_reg_read(struct spi_device *spi, u8 reg)
{
u8 rxbuf;
int retry_count;
int ret;
ret = b53_spi_read_reg(spi, reg, &rxbuf, 1);
if (ret)
return ret;
for (retry_count = 0; retry_count < 10; retry_count++) {
ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
if (ret)
return ret;
if (rxbuf & B53_SPI_CMD_RACK)
break;
mdelay(1);
}
if (retry_count == 10)
return -EIO;
return 0;
}
static int b53_spi_read(struct b53_device *dev, u8 page, u8 reg, u8 *data,
unsigned len)
{
struct spi_device *spi = dev->priv;
int ret;
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
ret = b53_spi_prepare_reg_read(spi, reg);
if (ret)
return ret;
return b53_spi_read_reg(spi, B53_SPI_DATA, data, len);
}
static int b53_spi_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
{
return b53_spi_read(dev, page, reg, val, 1);
}
static int b53_spi_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
{
int ret = b53_spi_read(dev, page, reg, (u8 *)val, 2);
if (!ret)
*val = le16_to_cpu(*val);
return ret;
}
static int b53_spi_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
{
int ret = b53_spi_read(dev, page, reg, (u8 *)val, 4);
if (!ret)
*val = le32_to_cpu(*val);
return ret;
}
static int b53_spi_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
{
int ret;
*val = 0;
ret = b53_spi_read(dev, page, reg, (u8 *)val, 6);
if (!ret)
*val = le64_to_cpu(*val);
return ret;
}
static int b53_spi_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
{
int ret = b53_spi_read(dev, page, reg, (u8 *)val, 8);
if (!ret)
*val = le64_to_cpu(*val);
return ret;
}
static int b53_spi_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
{
struct spi_device *spi = dev->priv;
int ret;
u8 txbuf[3];
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = reg;
txbuf[2] = value;
return spi_write(spi, txbuf, sizeof(txbuf));
}
static int b53_spi_write16(struct b53_device *dev, u8 page, u8 reg, u16 value)
{
struct spi_device *spi = dev->priv;
int ret;
u8 txbuf[4];
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = reg;
put_unaligned_le16(value, &txbuf[2]);
return spi_write(spi, txbuf, sizeof(txbuf));
}
static int b53_spi_write32(struct b53_device *dev, u8 page, u8 reg, u32 value)
{
struct spi_device *spi = dev->priv;
int ret;
u8 txbuf[6];
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = reg;
put_unaligned_le32(value, &txbuf[2]);
return spi_write(spi, txbuf, sizeof(txbuf));
}
static int b53_spi_write48(struct b53_device *dev, u8 page, u8 reg, u64 value)
{
struct spi_device *spi = dev->priv;
int ret;
u8 txbuf[10];
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = reg;
put_unaligned_le64(value, &txbuf[2]);
return spi_write(spi, txbuf, sizeof(txbuf) - 2);
}
static int b53_spi_write64(struct b53_device *dev, u8 page, u8 reg, u64 value)
{
struct spi_device *spi = dev->priv;
int ret;
u8 txbuf[10];
ret = b53_prepare_reg_access(spi, page);
if (ret)
return ret;
txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
txbuf[1] = reg;
put_unaligned_le64(value, &txbuf[2]);
return spi_write(spi, txbuf, sizeof(txbuf));
}
static struct b53_io_ops b53_spi_ops = {
.read8 = b53_spi_read8,
.read16 = b53_spi_read16,
.read32 = b53_spi_read32,
.read48 = b53_spi_read48,
.read64 = b53_spi_read64,
.write8 = b53_spi_write8,
.write16 = b53_spi_write16,
.write32 = b53_spi_write32,
.write48 = b53_spi_write48,
.write64 = b53_spi_write64,
};
static int b53_spi_probe(struct spi_device *spi)
{
struct b53_device *dev;
int ret;
dev = b53_switch_alloc(&spi->dev, &b53_spi_ops, spi);
if (!dev)
return -ENOMEM;
if (spi->dev.platform_data)
dev->pdata = spi->dev.platform_data;
ret = b53_switch_register(dev);
if (ret)
return ret;
spi_set_drvdata(spi, dev);
return 0;
}
static int b53_spi_remove(struct spi_device *spi)
{
struct b53_device *dev = spi_get_drvdata(spi);
if (dev)
b53_switch_remove(dev);
return 0;
}
static const struct of_device_id b53_of_match[] = {
{ .compatible = "brcm,bcm5325" },
{ .compatible = "brcm,bcm53115" },
{ .compatible = "brcm,bcm53125" },
{ .compatible = "brcm,bcm53128" },
{ .compatible = "brcm,bcm5365" },
{ .compatible = "brcm,bcm5395" },
{ .compatible = "brcm,bcm5397" },
{ .compatible = "brcm,bcm5398" },
{ /* sentinel */ },
};
static struct spi_driver b53_spi_driver = {
.driver = {
.name = "b53-switch",
.bus = &spi_bus_type,
.owner = THIS_MODULE,
.of_match_table = b53_of_match,
},
.probe = b53_spi_probe,
.remove = b53_spi_remove,
};
module_spi_driver(b53_spi_driver);
MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
MODULE_DESCRIPTION("B53 SPI access driver");
MODULE_LICENSE("Dual BSD/GPL");