diff options
Diffstat (limited to 'drivers/net/ethernet/wiznet/w5100-spi.c')
-rw-r--r-- | drivers/net/ethernet/wiznet/w5100-spi.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/net/ethernet/wiznet/w5100-spi.c b/drivers/net/ethernet/wiznet/w5100-spi.c new file mode 100644 index 0000000..32f406c --- /dev/null +++ b/drivers/net/ethernet/wiznet/w5100-spi.c @@ -0,0 +1,136 @@ +/* + * Ethernet driver for the WIZnet W5100 chip. + * + * Copyright (C) 2016 Akinobu Mita <akinobu.mita@gmail.com> + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/netdevice.h> +#include <linux/spi/spi.h> + +#include "w5100.h" + +#define W5100_SPI_WRITE_OPCODE 0xf0 +#define W5100_SPI_READ_OPCODE 0x0f + +static int w5100_spi_read(struct net_device *ndev, u16 addr) +{ + struct spi_device *spi = to_spi_device(ndev->dev.parent); + u8 cmd[3] = { W5100_SPI_READ_OPCODE, addr >> 8, addr & 0xff }; + u8 data; + int ret; + + ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, 1); + + return ret ? ret : data; +} + +static int w5100_spi_write(struct net_device *ndev, u16 addr, u8 data) +{ + struct spi_device *spi = to_spi_device(ndev->dev.parent); + u8 cmd[4] = { W5100_SPI_WRITE_OPCODE, addr >> 8, addr & 0xff, data}; + + return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0); +} + +static int w5100_spi_read16(struct net_device *ndev, u16 addr) +{ + u16 data; + int ret; + + ret = w5100_spi_read(ndev, addr); + if (ret < 0) + return ret; + data = ret << 8; + ret = w5100_spi_read(ndev, addr + 1); + + return ret < 0 ? ret : data | ret; +} + +static int w5100_spi_write16(struct net_device *ndev, u16 addr, u16 data) +{ + int ret; + + ret = w5100_spi_write(ndev, addr, data >> 8); + if (ret) + return ret; + + return w5100_spi_write(ndev, addr + 1, data & 0xff); +} + +static int w5100_spi_readbulk(struct net_device *ndev, u16 addr, u8 *buf, + int len) +{ + int i; + + for (i = 0; i < len; i++) { + int ret = w5100_spi_read(ndev, addr + i); + + if (ret < 0) + return ret; + buf[i] = ret; + } + + return 0; +} + +static int w5100_spi_writebulk(struct net_device *ndev, u16 addr, const u8 *buf, + int len) +{ + int i; + + for (i = 0; i < len; i++) { + int ret = w5100_spi_write(ndev, addr + i, buf[i]); + + if (ret) + return ret; + } + + return 0; +} + +static const struct w5100_ops w5100_spi_ops = { + .may_sleep = true, + .read = w5100_spi_read, + .write = w5100_spi_write, + .read16 = w5100_spi_read16, + .write16 = w5100_spi_write16, + .readbulk = w5100_spi_readbulk, + .writebulk = w5100_spi_writebulk, +}; + +static int w5100_spi_probe(struct spi_device *spi) +{ + return w5100_probe(&spi->dev, &w5100_spi_ops, 0, NULL, spi->irq, + -EINVAL); +} + +static int w5100_spi_remove(struct spi_device *spi) +{ + return w5100_remove(&spi->dev); +} + +static const struct spi_device_id w5100_spi_ids[] = { + { "w5100", 0 }, + {} +}; +MODULE_DEVICE_TABLE(spi, w5100_spi_ids); + +static struct spi_driver w5100_spi_driver = { + .driver = { + .name = "w5100", + .pm = &w5100_pm_ops, + }, + .probe = w5100_spi_probe, + .remove = w5100_spi_remove, + .id_table = w5100_spi_ids, +}; +module_spi_driver(w5100_spi_driver); + +MODULE_DESCRIPTION("WIZnet W5100 Ethernet driver for SPI mode"); +MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>"); +MODULE_LICENSE("GPL"); |