// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/* Copyright (c) 2016-2019 Mellanox Technologies. All rights reserved */

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/types.h>

#include "core.h"
#include "core_env.h"
#include "i2c.h"

static const char mlxsw_m_driver_name[] = "mlxsw_minimal";

struct mlxsw_m_port;

struct mlxsw_m {
	struct mlxsw_m_port **ports;
	int *module_to_port;
	struct mlxsw_core *core;
	const struct mlxsw_bus_info *bus_info;
	u8 base_mac[ETH_ALEN];
	u8 max_ports;
};

struct mlxsw_m_port {
	struct net_device *dev;
	struct mlxsw_m *mlxsw_m;
	u8 local_port;
	u8 module;
};

static int mlxsw_m_base_mac_get(struct mlxsw_m *mlxsw_m)
{
	char spad_pl[MLXSW_REG_SPAD_LEN] = {0};
	int err;

	err = mlxsw_reg_query(mlxsw_m->core, MLXSW_REG(spad), spad_pl);
	if (err)
		return err;
	mlxsw_reg_spad_base_mac_memcpy_from(spad_pl, mlxsw_m->base_mac);
	return 0;
}

static int mlxsw_m_port_dummy_open_stop(struct net_device *dev)
{
	return 0;
}

static int
mlxsw_m_port_get_phys_port_name(struct net_device *dev, char *name, size_t len)
{
	struct mlxsw_m_port *mlxsw_m_port = netdev_priv(dev);
	struct mlxsw_core *core = mlxsw_m_port->mlxsw_m->core;
	u8 local_port = mlxsw_m_port->local_port;

	return mlxsw_core_port_get_phys_port_name(core, local_port, name, len);
}

static int mlxsw_m_port_get_port_parent_id(struct net_device *dev,
					   struct netdev_phys_item_id *ppid)
{
	struct mlxsw_m_port *mlxsw_m_port = netdev_priv(dev);
	struct mlxsw_m *mlxsw_m = mlxsw_m_port->mlxsw_m;

	ppid->id_len = sizeof(mlxsw_m->base_mac);
	memcpy(&ppid->id, &mlxsw_m->base_mac, ppid->id_len);

	return 0;
}

static const struct net_device_ops mlxsw_m_port_netdev_ops = {
	.ndo_open		= mlxsw_m_port_dummy_open_stop,
	.ndo_stop		= mlxsw_m_port_dummy_open_stop,
	.ndo_get_phys_port_name	= mlxsw_m_port_get_phys_port_name,
	.ndo_get_port_parent_id	= mlxsw_m_port_get_port_parent_id,
};

static int mlxsw_m_get_module_info(struct net_device *netdev,
				   struct ethtool_modinfo *modinfo)
{
	struct mlxsw_m_port *mlxsw_m_port = netdev_priv(netdev);
	struct mlxsw_core *core = mlxsw_m_port->mlxsw_m->core;

	return mlxsw_env_get_module_info(core, mlxsw_m_port->module, modinfo);
}

static int
mlxsw_m_get_module_eeprom(struct net_device *netdev, struct ethtool_eeprom *ee,
			  u8 *data)
{
	struct mlxsw_m_port *mlxsw_m_port = netdev_priv(netdev);
	struct mlxsw_core *core = mlxsw_m_port->mlxsw_m->core;

	return mlxsw_env_get_module_eeprom(netdev, core, mlxsw_m_port->module,
					   ee, data);
}

static const struct ethtool_ops mlxsw_m_port_ethtool_ops = {
	.get_module_info	= mlxsw_m_get_module_info,
	.get_module_eeprom	= mlxsw_m_get_module_eeprom,
};

static int
mlxsw_m_port_module_info_get(struct mlxsw_m *mlxsw_m, u8 local_port,
			     u8 *p_module, u8 *p_width)
{
	char pmlp_pl[MLXSW_REG_PMLP_LEN];
	int err;

	mlxsw_reg_pmlp_pack(pmlp_pl, local_port);
	err = mlxsw_reg_query(mlxsw_m->core, MLXSW_REG(pmlp), pmlp_pl);
	if (err)
		return err;
	*p_module = mlxsw_reg_pmlp_module_get(pmlp_pl, 0);
	*p_width = mlxsw_reg_pmlp_width_get(pmlp_pl);

	return 0;
}

static int
mlxsw_m_port_dev_addr_get(struct mlxsw_m_port *mlxsw_m_port)
{
	struct mlxsw_m *mlxsw_m = mlxsw_m_port->mlxsw_m;
	struct net_device *dev = mlxsw_m_port->dev;
	char ppad_pl[MLXSW_REG_PPAD_LEN];
	int err;

	mlxsw_reg_ppad_pack(ppad_pl, false, 0);
	err = mlxsw_reg_query(mlxsw_m->core, MLXSW_REG(ppad), ppad_pl);
	if (err)
		return err;
	mlxsw_reg_ppad_mac_memcpy_from(ppad_pl, dev->dev_addr);
	/* The last byte value in base mac address is guaranteed
	 * to be such it does not overflow when adding local_port
	 * value.
	 */
	dev->dev_addr[ETH_ALEN - 1] += mlxsw_m_port->module + 1;
	return 0;
}

static int
mlxsw_m_port_create(struct mlxsw_m *mlxsw_m, u8 local_port, u8 module)
{
	struct mlxsw_m_port *mlxsw_m_port;
	struct net_device *dev;
	int err;

	err = mlxsw_core_port_init(mlxsw_m->core, local_port);
	if (err) {
		dev_err(mlxsw_m->bus_info->dev, "Port %d: Failed to init core port\n",
			local_port);
		return err;
	}

	dev = alloc_etherdev(sizeof(struct mlxsw_m_port));
	if (!dev) {
		err = -ENOMEM;
		goto err_alloc_etherdev;
	}

	SET_NETDEV_DEV(dev, mlxsw_m->bus_info->dev);
	mlxsw_m_port = netdev_priv(dev);
	mlxsw_m_port->dev = dev;
	mlxsw_m_port->mlxsw_m = mlxsw_m;
	mlxsw_m_port->local_port = local_port;
	mlxsw_m_port->module = module;

	dev->netdev_ops = &mlxsw_m_port_netdev_ops;
	dev->ethtool_ops = &mlxsw_m_port_ethtool_ops;

	err = mlxsw_m_port_dev_addr_get(mlxsw_m_port);
	if (err) {
		dev_err(mlxsw_m->bus_info->dev, "Port %d: Unable to get port mac address\n",
			mlxsw_m_port->local_port);
		goto err_dev_addr_get;
	}

	netif_carrier_off(dev);
	mlxsw_m->ports[local_port] = mlxsw_m_port;
	err = register_netdev(dev);
	if (err) {
		dev_err(mlxsw_m->bus_info->dev, "Port %d: Failed to register netdev\n",
			mlxsw_m_port->local_port);
		goto err_register_netdev;
	}

	mlxsw_core_port_eth_set(mlxsw_m->core, mlxsw_m_port->local_port,
				mlxsw_m_port, dev, module + 1, false, 0);

	return 0;

err_register_netdev:
	mlxsw_m->ports[local_port] = NULL;
	free_netdev(dev);
err_dev_addr_get:
err_alloc_etherdev:
	mlxsw_core_port_fini(mlxsw_m->core, local_port);
	return err;
}

static void mlxsw_m_port_remove(struct mlxsw_m *mlxsw_m, u8 local_port)
{
	struct mlxsw_m_port *mlxsw_m_port = mlxsw_m->ports[local_port];

	mlxsw_core_port_clear(mlxsw_m->core, local_port, mlxsw_m);
	unregister_netdev(mlxsw_m_port->dev); /* This calls ndo_stop */
	mlxsw_m->ports[local_port] = NULL;
	free_netdev(mlxsw_m_port->dev);
	mlxsw_core_port_fini(mlxsw_m->core, local_port);
}

static int mlxsw_m_port_module_map(struct mlxsw_m *mlxsw_m, u8 local_port,
				   u8 *last_module)
{
	u8 module, width;
	int err;

	/* Fill out to local port mapping array */
	err = mlxsw_m_port_module_info_get(mlxsw_m, local_port, &module,
					   &width);
	if (err)
		return err;

	if (!width)
		return 0;
	/* Skip, if port belongs to the cluster */
	if (module == *last_module)
		return 0;
	*last_module = module;
	mlxsw_m->module_to_port[module] = ++mlxsw_m->max_ports;

	return 0;
}

static void mlxsw_m_port_module_unmap(struct mlxsw_m *mlxsw_m, u8 module)
{
	mlxsw_m->module_to_port[module] = -1;
}

static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
{
	unsigned int max_ports = mlxsw_core_max_ports(mlxsw_m->core);
	u8 last_module = max_ports;
	int i;
	int err;

	mlxsw_m->ports = kcalloc(max_ports, sizeof(*mlxsw_m->ports),
				 GFP_KERNEL);
	if (!mlxsw_m->ports)
		return -ENOMEM;

	mlxsw_m->module_to_port = kmalloc_array(max_ports, sizeof(int),
						GFP_KERNEL);
	if (!mlxsw_m->module_to_port) {
		err = -ENOMEM;
		goto err_module_to_port_alloc;
	}

	/* Invalidate the entries of module to local port mapping array */
	for (i = 0; i < max_ports; i++)
		mlxsw_m->module_to_port[i] = -1;

	/* Fill out module to local port mapping array */
	for (i = 1; i < max_ports; i++) {
		err = mlxsw_m_port_module_map(mlxsw_m, i, &last_module);
		if (err)
			goto err_module_to_port_map;
	}

	/* Create port objects for each valid entry */
	for (i = 0; i < mlxsw_m->max_ports; i++) {
		if (mlxsw_m->module_to_port[i] > 0) {
			err = mlxsw_m_port_create(mlxsw_m,
						  mlxsw_m->module_to_port[i],
						  i);
			if (err)
				goto err_module_to_port_create;
		}
	}

	return 0;

err_module_to_port_create:
	for (i--; i >= 0; i--) {
		if (mlxsw_m->module_to_port[i] > 0)
			mlxsw_m_port_remove(mlxsw_m,
					    mlxsw_m->module_to_port[i]);
	}
	i = max_ports;
err_module_to_port_map:
	for (i--; i > 0; i--)
		mlxsw_m_port_module_unmap(mlxsw_m, i);
	kfree(mlxsw_m->module_to_port);
err_module_to_port_alloc:
	kfree(mlxsw_m->ports);
	return err;
}

static void mlxsw_m_ports_remove(struct mlxsw_m *mlxsw_m)
{
	int i;

	for (i = 0; i < mlxsw_m->max_ports; i++) {
		if (mlxsw_m->module_to_port[i] > 0) {
			mlxsw_m_port_remove(mlxsw_m,
					    mlxsw_m->module_to_port[i]);
			mlxsw_m_port_module_unmap(mlxsw_m, i);
		}
	}

	kfree(mlxsw_m->module_to_port);
	kfree(mlxsw_m->ports);
}

static int mlxsw_m_init(struct mlxsw_core *mlxsw_core,
			const struct mlxsw_bus_info *mlxsw_bus_info)
{
	struct mlxsw_m *mlxsw_m = mlxsw_core_driver_priv(mlxsw_core);
	int err;

	mlxsw_m->core = mlxsw_core;
	mlxsw_m->bus_info = mlxsw_bus_info;

	err = mlxsw_m_base_mac_get(mlxsw_m);
	if (err) {
		dev_err(mlxsw_m->bus_info->dev, "Failed to get base mac\n");
		return err;
	}

	err = mlxsw_m_ports_create(mlxsw_m);
	if (err) {
		dev_err(mlxsw_m->bus_info->dev, "Failed to create ports\n");
		return err;
	}

	return 0;
}

static void mlxsw_m_fini(struct mlxsw_core *mlxsw_core)
{
	struct mlxsw_m *mlxsw_m = mlxsw_core_driver_priv(mlxsw_core);

	mlxsw_m_ports_remove(mlxsw_m);
}

static const struct mlxsw_config_profile mlxsw_m_config_profile;

static struct mlxsw_driver mlxsw_m_driver = {
	.kind			= mlxsw_m_driver_name,
	.priv_size		= sizeof(struct mlxsw_m),
	.init			= mlxsw_m_init,
	.fini			= mlxsw_m_fini,
	.profile		= &mlxsw_m_config_profile,
	.res_query_enabled	= true,
};

static const struct i2c_device_id mlxsw_m_i2c_id[] = {
	{ "mlxsw_minimal", 0},
	{ },
};

static struct i2c_driver mlxsw_m_i2c_driver = {
	.driver.name = "mlxsw_minimal",
	.class = I2C_CLASS_HWMON,
	.id_table = mlxsw_m_i2c_id,
};

static int __init mlxsw_m_module_init(void)
{
	int err;

	err = mlxsw_core_driver_register(&mlxsw_m_driver);
	if (err)
		return err;

	err = mlxsw_i2c_driver_register(&mlxsw_m_i2c_driver);
	if (err)
		goto err_i2c_driver_register;

	return 0;

err_i2c_driver_register:
	mlxsw_core_driver_unregister(&mlxsw_m_driver);

	return err;
}

static void __exit mlxsw_m_module_exit(void)
{
	mlxsw_i2c_driver_unregister(&mlxsw_m_i2c_driver);
	mlxsw_core_driver_unregister(&mlxsw_m_driver);
}

module_init(mlxsw_m_module_init);
module_exit(mlxsw_m_module_exit);

MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
MODULE_DESCRIPTION("Mellanox minimal driver");
MODULE_DEVICE_TABLE(i2c, mlxsw_m_i2c_id);