On Wed, Dec 19, 2018 at 4:41 AM <tristram...@microchip.com> wrote:
>
> From: Tristram Ha <tristram...@microchip.com>
>
> Add KSZ9477 I2C driver support. The code ksz9477.c and ksz_common.c are
> used together to generate the I2C driver.
>
> Signed-off-by: Tristram Ha <tristram...@microchip.com>
> ---
> v1
> - Return error code from i2c_transfer
> - Change GPL license
> - Change author
>
> drivers/net/dsa/microchip/Kconfig | 6 +
> drivers/net/dsa/microchip/Makefile | 1 +
> drivers/net/dsa/microchip/ksz9477_i2c.c | 196
> ++++++++++++++++++++++++++++++++
> drivers/net/dsa/microchip/ksz_i2c.h | 69 +++++++++++
> 4 files changed, 272 insertions(+)
> create mode 100644 drivers/net/dsa/microchip/ksz9477_i2c.c
> create mode 100644 drivers/net/dsa/microchip/ksz_i2c.h
>
> diff --git a/drivers/net/dsa/microchip/Kconfig
> b/drivers/net/dsa/microchip/Kconfig
> index bea29fd..fd94441 100644
> --- a/drivers/net/dsa/microchip/Kconfig
> +++ b/drivers/net/dsa/microchip/Kconfig
> @@ -9,6 +9,12 @@ menuconfig NET_DSA_MICROCHIP_KSZ9477
> help
> This driver adds support for Microchip KSZ9477 switch chips.
>
> +config NET_DSA_MICROCHIP_KSZ9477_I2C
> + tristate "KSZ9477 series I2C connected switch driver"
> + depends on NET_DSA_MICROCHIP_KSZ9477 && I2C
> + help
> + Select to enable support for registering switches configured
> through I2C.
> +
> config NET_DSA_MICROCHIP_KSZ9477_SPI
> tristate "KSZ9477 series SPI connected switch driver"
> depends on NET_DSA_MICROCHIP_KSZ9477 && SPI
> diff --git a/drivers/net/dsa/microchip/Makefile
> b/drivers/net/dsa/microchip/Makefile
> index 3142c18..dbcc5db 100644
> --- a/drivers/net/dsa/microchip/Makefile
> +++ b/drivers/net/dsa/microchip/Makefile
> @@ -1,3 +1,4 @@
> obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ_COMMON) += ksz_common.o
> obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477) += ksz9477.o
> +obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477_I2C) += ksz9477_i2c.o
> obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477_SPI) += ksz9477_spi.o
> diff --git a/drivers/net/dsa/microchip/ksz9477_i2c.c
> b/drivers/net/dsa/microchip/ksz9477_i2c.c
> new file mode 100644
> index 0000000..29511e9
> --- /dev/null
> +++ b/drivers/net/dsa/microchip/ksz9477_i2c.c
> @@ -0,0 +1,196 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Microchip KSZ9477 series register access through I2C
> + *
> + * Copyright (C) 2018 Microchip Technology Inc.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +
> +#include "ksz_priv.h"
> +#include "ksz_i2c.h"
> +
> +/* Enough to read all switch port registers. */
> +#define I2C_TX_BUF_LEN 0x100
> +
> +static int ksz9477_i2c_read_reg(struct i2c_client *i2c, u32 reg, u8 *val,
> + unsigned int len)
> +{
> + struct i2c_msg msg[2];
> + int ret;
> +
> + val[0] = (u8)(reg >> 8);
> + val[1] = (u8)reg;
> +
> + msg[0].addr = i2c->addr;
> + msg[0].flags = 0;
> + msg[0].len = 2;
> + msg[0].buf = val;
> +
> + msg[1].addr = i2c->addr;
> + msg[1].flags = I2C_M_RD;
> + msg[1].len = len;
> + msg[1].buf = &val[2];
> +
> + ret = i2c_transfer(i2c->adapter, msg, 2);
> + if (ret == 2)
> + ret = 0;
> + return ret;
> +}
> +
> +static int ksz9477_i2c_write_reg(struct i2c_client *i2c, u32 reg, u8 *val,
> + unsigned int len)
> +{
> + struct i2c_msg msg;
> + int ret;
> +
> + val[0] = (u8)(reg >> 8);
> + val[1] = (u8)reg;
> +
> + msg.addr = i2c->addr;
> + msg.flags = 0;
> + msg.len = 2 + len;
> + msg.buf = val;
> +
> + ret = i2c_transfer(i2c->adapter, &msg, 1);
> + if (ret == 1)
> + ret = 0;
> + return ret;
> +}
> +
> +static int ksz_i2c_read(struct ksz_device *dev, u32 reg, u8 *data,
> + unsigned int len)
> +{
> + struct i2c_client *i2c = dev->priv;
> + int ret;
> +
> + ret = ksz9477_i2c_read_reg(i2c, reg, dev->txbuf, len);
> + if (!ret)
> + memcpy(data, &dev->txbuf[2], len);
> + return ret;
> +}
> +
> +static int ksz_i2c_write(struct ksz_device *dev, u32 reg, void *data,
> + unsigned int len)
> +{
> + struct i2c_client *i2c = dev->priv;
> +
> + if (len > I2C_TX_BUF_LEN)
> + len = I2C_TX_BUF_LEN;
> + memcpy(&dev->txbuf[2], data, len);
> + return ksz9477_i2c_write_reg(i2c, reg, dev->txbuf, len);
> +}
> +
> +static int ksz_i2c_read24(struct ksz_device *dev, u32 reg, u32 *val)
> +{
> + int ret;
> +
> + *val = 0;
> + ret = ksz_i2c_read(dev, reg, (u8 *)val, 3);
> + if (!ret) {
> + *val = be32_to_cpu(*val);
> + /* convert to 24bit */
> + *val >>= 8;
> + }
> +
> + return ret;
> +}
> +
> +static int ksz_i2c_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_i2c_write(dev, reg, &value, 3);
> +}
> +
> +static const struct ksz_io_ops ksz9477_i2c_ops = {
> + .read8 = ksz_i2c_read8,
> + .read16 = ksz_i2c_read16,
> + .read24 = ksz_i2c_read24,
> + .read32 = ksz_i2c_read32,
> + .write8 = ksz_i2c_write8,
> + .write16 = ksz_i2c_write16,
> + .write24 = ksz_i2c_write24,
> + .write32 = ksz_i2c_write32,
> + .get = ksz_i2c_get,
> + .set = ksz_i2c_set,
> +};
> +
> +static int ksz9477_i2c_probe(struct i2c_client *i2c,
> + const struct i2c_device_id *i2c_id)
> +{
> + struct ksz_device *dev;
> + int ret;
> +
> + dev = ksz_switch_alloc(&i2c->dev, &ksz9477_i2c_ops, i2c);
> + if (!dev)
> + return -ENOMEM;
> +
> + if (i2c->dev.platform_data)
> + dev->pdata = i2c->dev.platform_data;
> +
> + dev->txbuf = devm_kzalloc(dev->dev, 2 + I2C_TX_BUF_LEN, GFP_KERNEL);
> +
> + ret = ksz9477_switch_register(dev);
> +
> + /* Main DSA driver may not be started yet. */
> + if (ret)
> + return ret;
> +
> + i2c_set_clientdata(i2c, dev);
> +
> + return 0;
> +}
> +
> +static int ksz9477_i2c_remove(struct i2c_client *i2c)
> +{
> + struct ksz_device *dev = i2c_get_clientdata(i2c);
> +
> + if (dev)
> + ksz_switch_remove(dev);
> +
> + return 0;
> +}
> +
> +static void ksz9477_i2c_shutdown(struct i2c_client *i2c)
> +{
> + struct ksz_device *dev = i2c_get_clientdata(i2c);
> +
> + if (dev && dev->dev_ops->shutdown)
> + dev->dev_ops->shutdown(dev);
> +}
> +
> +static const struct i2c_device_id ksz9477_i2c_id[] = {
> + { "ksz9477-switch", 0 },
> + {},
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, ksz9477_i2c_id);
> +
> +static const struct of_device_id ksz9477_dt_ids[] = {
> + { .compatible = "microchip,ksz9477" },
> + { .compatible = "microchip,ksz9897" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, ksz9477_dt_ids);
> +
> +static struct i2c_driver ksz9477_i2c_driver = {
> + .driver = {
> + .name = "ksz9477-switch",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(ksz9477_dt_ids),
> + },
> + .probe = ksz9477_i2c_probe,
> + .remove = ksz9477_i2c_remove,
> + .shutdown = ksz9477_i2c_shutdown,
> + .id_table = ksz9477_i2c_id,
> +};
> +
> +module_i2c_driver(ksz9477_i2c_driver);
> +
> +MODULE_AUTHOR("Tristram Ha <tristram...@microchip.com>");
> +MODULE_DESCRIPTION("Microchip KSZ9477 Series Switch I2C access Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/net/dsa/microchip/ksz_i2c.h
> b/drivers/net/dsa/microchip/ksz_i2c.h
> new file mode 100644
> index 0000000..b9af0a8
> --- /dev/null
> +++ b/drivers/net/dsa/microchip/ksz_i2c.h
> @@ -0,0 +1,69 @@
> +/* SPDX-License-Identifier: GPL-2.0
> + * Microchip KSZ series I2C access common header
> + *
> + * Copyright (C) 2018 Microchip Technology Inc.
> + * Tristram Ha <tristram...@microchip.com>
> + */
> +
> +#ifndef __KSZ_I2C_H
> +#define __KSZ_I2C_H
> +
> +/* Chip dependent I2C access */
> +static int ksz_i2c_read(struct ksz_device *dev, u32 reg, u8 *data,
> + unsigned int len);
> +static int ksz_i2c_write(struct ksz_device *dev, u32 reg, void *data,
> + unsigned int len);
> +
> +static int ksz_i2c_read8(struct ksz_device *dev, u32 reg, u8 *val)
> +{
> + return ksz_i2c_read(dev, reg, val, 1);
> +}
> +
> +static int ksz_i2c_read16(struct ksz_device *dev, u32 reg, u16 *val)
> +{
> + int ret = ksz_i2c_read(dev, reg, (u8 *)val, 2);
> +
> + if (!ret)
> + *val = be16_to_cpu(*val);
> +
> + return ret;
> +}
> +
> +static int ksz_i2c_read32(struct ksz_device *dev, u32 reg, u32 *val)
> +{
> + int ret = ksz_i2c_read(dev, reg, (u8 *)val, 4);
> +
> + if (!ret)
> + *val = be32_to_cpu(*val);
> +
> + return ret;
> +}
> +
> +static int ksz_i2c_write8(struct ksz_device *dev, u32 reg, u8 value)
> +{
> + return ksz_i2c_write(dev, reg, &value, 1);
> +}
> +
> +static int ksz_i2c_write16(struct ksz_device *dev, u32 reg, u16 value)
> +{
> + value = cpu_to_be16(value);
> + return ksz_i2c_write(dev, reg, &value, 2);
> +}
> +
> +static int ksz_i2c_write32(struct ksz_device *dev, u32 reg, u32 value)
> +{
> + value = cpu_to_be32(value);
> + return ksz_i2c_write(dev, reg, &value, 4);
> +}
> +
> +static int ksz_i2c_get(struct ksz_device *dev, u32 reg, void *data, size_t
> len)
> +{
> + return ksz_i2c_read(dev, reg, data, len);
> +}
> +
> +static int ksz_i2c_set(struct ksz_device *dev, u32 reg, void *data, size_t
> len)
> +{
> + return ksz_i2c_write(dev, reg, data, len);
> +}
> +
> +#endif
> --
> 1.9.1
>
I don't know if at the end this is going to be changed together with
spi etc to use regmap API but I tested this code as it is and it
works. So you can add my Tested-by if you want:
Tested-by: Sergio Paracuellos <sergio.paracuel...@gmail.com>
Best regards,
Sergio Paracuellos
