diff options
Diffstat (limited to 'drivers/net/dsa/b53/b53_spi.c')
| -rw-r--r-- | drivers/net/dsa/b53/b53_spi.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/net/dsa/b53/b53_spi.c b/drivers/net/dsa/b53/b53_spi.c new file mode 100644 index 000000000..308f15d38 --- /dev/null +++ b/drivers/net/dsa/b53/b53_spi.c @@ -0,0 +1,376 @@ +/* + * 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/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spi/spi.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 int 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 int 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) +{ + __le16 value; + int ret; + + ret = b53_spi_read(dev, page, reg, (u8 *)&value, 2); + + if (!ret) + *val = le16_to_cpu(value); + + return ret; +} + +static int b53_spi_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val) +{ + __le32 value; + int ret; + + ret = b53_spi_read(dev, page, reg, (u8 *)&value, 4); + + if (!ret) + *val = le32_to_cpu(value); + + return ret; +} + +static int b53_spi_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val) +{ + __le64 value; + int ret; + + *val = 0; + ret = b53_spi_read(dev, page, reg, (u8 *)&value, 6); + if (!ret) + *val = le64_to_cpu(value); + + return ret; +} + +static int b53_spi_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val) +{ + __le64 value; + int ret; + + ret = b53_spi_read(dev, page, reg, (u8 *)&value, 8); + + if (!ret) + *val = le64_to_cpu(value); + + 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 const 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 void b53_spi_remove(struct spi_device *spi) +{ + struct b53_device *dev = spi_get_drvdata(spi); + + if (dev) + b53_switch_remove(dev); +} + +static void b53_spi_shutdown(struct spi_device *spi) +{ + struct b53_device *dev = spi_get_drvdata(spi); + + if (dev) + b53_switch_shutdown(dev); + + spi_set_drvdata(spi, NULL); +} + +static const struct of_device_id b53_spi_of_match[] = { + { .compatible = "brcm,bcm5325" }, + { .compatible = "brcm,bcm5365" }, + { .compatible = "brcm,bcm5395" }, + { .compatible = "brcm,bcm5397" }, + { .compatible = "brcm,bcm5398" }, + { .compatible = "brcm,bcm53115" }, + { .compatible = "brcm,bcm53125" }, + { .compatible = "brcm,bcm53128" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, b53_spi_of_match); + +static const struct spi_device_id b53_spi_ids[] = { + { .name = "bcm5325" }, + { .name = "bcm5365" }, + { .name = "bcm5395" }, + { .name = "bcm5397" }, + { .name = "bcm5398" }, + { .name = "bcm53115" }, + { .name = "bcm53125" }, + { .name = "bcm53128" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(spi, b53_spi_ids); + +static struct spi_driver b53_spi_driver = { + .driver = { + .name = "b53-switch", + .of_match_table = b53_spi_of_match, + }, + .probe = b53_spi_probe, + .remove = b53_spi_remove, + .shutdown = b53_spi_shutdown, + .id_table = b53_spi_ids, +}; + +module_spi_driver(b53_spi_driver); + +MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>"); +MODULE_DESCRIPTION("B53 SPI access driver"); +MODULE_LICENSE("Dual BSD/GPL"); |