diff options
Diffstat (limited to 'drivers/net/dsa/vitesse-vsc73xx-spi.c')
| -rw-r--r-- | drivers/net/dsa/vitesse-vsc73xx-spi.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/net/dsa/vitesse-vsc73xx-spi.c b/drivers/net/dsa/vitesse-vsc73xx-spi.c new file mode 100644 index 000000000..85b9a0f51 --- /dev/null +++ b/drivers/net/dsa/vitesse-vsc73xx-spi.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0 +/* DSA driver for: + * Vitesse VSC7385 SparX-G5 5+1-port Integrated Gigabit Ethernet Switch + * Vitesse VSC7388 SparX-G8 8-port Integrated Gigabit Ethernet Switch + * Vitesse VSC7395 SparX-G5e 5+1-port Integrated Gigabit Ethernet Switch + * Vitesse VSC7398 SparX-G8e 8-port Integrated Gigabit Ethernet Switch + * + * This driver takes control of the switch chip over SPI and + * configures it to route packages around when connected to a CPU port. + * + * Copyright (C) 2018 Linus Wallej <linus.walleij@linaro.org> + * Includes portions of code from the firmware uploader by: + * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org> + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/spi/spi.h> + +#include "vitesse-vsc73xx.h" + +#define VSC73XX_CMD_SPI_MODE_READ 0 +#define VSC73XX_CMD_SPI_MODE_WRITE 1 +#define VSC73XX_CMD_SPI_MODE_SHIFT 4 +#define VSC73XX_CMD_SPI_BLOCK_SHIFT 5 +#define VSC73XX_CMD_SPI_BLOCK_MASK 0x7 +#define VSC73XX_CMD_SPI_SUBBLOCK_MASK 0xf + +/* + * struct vsc73xx_spi - VSC73xx SPI state container + */ +struct vsc73xx_spi { + struct spi_device *spi; + struct mutex lock; /* Protects SPI traffic */ + struct vsc73xx vsc; +}; + +static const struct vsc73xx_ops vsc73xx_spi_ops; + +static u8 vsc73xx_make_addr(u8 mode, u8 block, u8 subblock) +{ + u8 ret; + + ret = + (block & VSC73XX_CMD_SPI_BLOCK_MASK) << VSC73XX_CMD_SPI_BLOCK_SHIFT; + ret |= (mode & 1) << VSC73XX_CMD_SPI_MODE_SHIFT; + ret |= subblock & VSC73XX_CMD_SPI_SUBBLOCK_MASK; + + return ret; +} + +static int vsc73xx_spi_read(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg, + u32 *val) +{ + struct vsc73xx_spi *vsc_spi = vsc->priv; + struct spi_transfer t[2]; + struct spi_message m; + u8 cmd[4]; + u8 buf[4]; + int ret; + + if (!vsc73xx_is_addr_valid(block, subblock)) + return -EINVAL; + + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = cmd; + t[0].len = sizeof(cmd); + spi_message_add_tail(&t[0], &m); + + t[1].rx_buf = buf; + t[1].len = sizeof(buf); + spi_message_add_tail(&t[1], &m); + + cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_SPI_MODE_READ, block, subblock); + cmd[1] = reg; + cmd[2] = 0; + cmd[3] = 0; + + mutex_lock(&vsc_spi->lock); + ret = spi_sync(vsc_spi->spi, &m); + mutex_unlock(&vsc_spi->lock); + + if (ret) + return ret; + + *val = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3]; + + return 0; +} + +static int vsc73xx_spi_write(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg, + u32 val) +{ + struct vsc73xx_spi *vsc_spi = vsc->priv; + struct spi_transfer t[2]; + struct spi_message m; + u8 cmd[2]; + u8 buf[4]; + int ret; + + if (!vsc73xx_is_addr_valid(block, subblock)) + return -EINVAL; + + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = cmd; + t[0].len = sizeof(cmd); + spi_message_add_tail(&t[0], &m); + + t[1].tx_buf = buf; + t[1].len = sizeof(buf); + spi_message_add_tail(&t[1], &m); + + cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_SPI_MODE_WRITE, block, subblock); + cmd[1] = reg; + + buf[0] = (val >> 24) & 0xff; + buf[1] = (val >> 16) & 0xff; + buf[2] = (val >> 8) & 0xff; + buf[3] = val & 0xff; + + mutex_lock(&vsc_spi->lock); + ret = spi_sync(vsc_spi->spi, &m); + mutex_unlock(&vsc_spi->lock); + + return ret; +} + +static int vsc73xx_spi_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct vsc73xx_spi *vsc_spi; + int ret; + + vsc_spi = devm_kzalloc(dev, sizeof(*vsc_spi), GFP_KERNEL); + if (!vsc_spi) + return -ENOMEM; + + spi_set_drvdata(spi, vsc_spi); + vsc_spi->spi = spi_dev_get(spi); + vsc_spi->vsc.dev = dev; + vsc_spi->vsc.priv = vsc_spi; + vsc_spi->vsc.ops = &vsc73xx_spi_ops; + mutex_init(&vsc_spi->lock); + + spi->mode = SPI_MODE_0; + spi->bits_per_word = 8; + ret = spi_setup(spi); + if (ret < 0) { + dev_err(dev, "spi setup failed.\n"); + return ret; + } + + return vsc73xx_probe(&vsc_spi->vsc); +} + +static void vsc73xx_spi_remove(struct spi_device *spi) +{ + struct vsc73xx_spi *vsc_spi = spi_get_drvdata(spi); + + if (!vsc_spi) + return; + + vsc73xx_remove(&vsc_spi->vsc); +} + +static void vsc73xx_spi_shutdown(struct spi_device *spi) +{ + struct vsc73xx_spi *vsc_spi = spi_get_drvdata(spi); + + if (!vsc_spi) + return; + + vsc73xx_shutdown(&vsc_spi->vsc); + + spi_set_drvdata(spi, NULL); +} + +static const struct vsc73xx_ops vsc73xx_spi_ops = { + .read = vsc73xx_spi_read, + .write = vsc73xx_spi_write, +}; + +static const struct of_device_id vsc73xx_of_match[] = { + { + .compatible = "vitesse,vsc7385", + }, + { + .compatible = "vitesse,vsc7388", + }, + { + .compatible = "vitesse,vsc7395", + }, + { + .compatible = "vitesse,vsc7398", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, vsc73xx_of_match); + +static const struct spi_device_id vsc73xx_spi_ids[] = { + { "vsc7385" }, + { "vsc7388" }, + { "vsc7395" }, + { "vsc7398" }, + { }, +}; +MODULE_DEVICE_TABLE(spi, vsc73xx_spi_ids); + +static struct spi_driver vsc73xx_spi_driver = { + .probe = vsc73xx_spi_probe, + .remove = vsc73xx_spi_remove, + .shutdown = vsc73xx_spi_shutdown, + .id_table = vsc73xx_spi_ids, + .driver = { + .name = "vsc73xx-spi", + .of_match_table = vsc73xx_of_match, + }, +}; +module_spi_driver(vsc73xx_spi_driver); + +MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); +MODULE_DESCRIPTION("Vitesse VSC7385/7388/7395/7398 SPI driver"); +MODULE_LICENSE("GPL v2"); |