root/net/ethtool/pse-pd.c
// SPDX-License-Identifier: GPL-2.0-only
//
// ethtool interface for Ethernet PSE (Power Sourcing Equipment)
// and PD (Powered Device)
//
// Copyright (c) 2022 Pengutronix, Oleksij Rempel <kernel@pengutronix.de>
//

#include "common.h"
#include "linux/pse-pd/pse.h"
#include "netlink.h"
#include <linux/ethtool_netlink.h>
#include <linux/ethtool.h>
#include <linux/export.h>
#include <linux/phy.h>

struct pse_req_info {
        struct ethnl_req_info base;
};

struct pse_reply_data {
        struct ethnl_reply_data base;
        struct ethtool_pse_control_status status;
};

#define PSE_REPDATA(__reply_base) \
        container_of(__reply_base, struct pse_reply_data, base)

/* PSE_GET */

const struct nla_policy ethnl_pse_get_policy[ETHTOOL_A_PSE_HEADER + 1] = {
        [ETHTOOL_A_PSE_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy_phy),
};

static int pse_get_pse_attributes(struct phy_device *phydev,
                                  struct netlink_ext_ack *extack,
                                  struct pse_reply_data *data)
{
        if (!phydev) {
                NL_SET_ERR_MSG(extack, "No PHY found");
                return -EOPNOTSUPP;
        }

        if (!phydev->psec) {
                NL_SET_ERR_MSG(extack, "No PSE is attached");
                return -EOPNOTSUPP;
        }

        memset(&data->status, 0, sizeof(data->status));

        return pse_ethtool_get_status(phydev->psec, extack, &data->status);
}

static int pse_prepare_data(const struct ethnl_req_info *req_base,
                            struct ethnl_reply_data *reply_base,
                            const struct genl_info *info)
{
        struct pse_reply_data *data = PSE_REPDATA(reply_base);
        struct net_device *dev = reply_base->dev;
        struct nlattr **tb = info->attrs;
        struct phy_device *phydev;
        int ret;

        ret = ethnl_ops_begin(dev);
        if (ret < 0)
                return ret;

        phydev = ethnl_req_get_phydev(req_base, tb, ETHTOOL_A_PSE_HEADER,
                                      info->extack);
        if (IS_ERR(phydev))
                return -ENODEV;

        ret = pse_get_pse_attributes(phydev, info->extack, data);

        ethnl_ops_complete(dev);

        return ret;
}

static int pse_reply_size(const struct ethnl_req_info *req_base,
                          const struct ethnl_reply_data *reply_base)
{
        const struct pse_reply_data *data = PSE_REPDATA(reply_base);
        const struct ethtool_pse_control_status *st = &data->status;
        int len = 0;

        if (st->pw_d_id)
                len += nla_total_size(sizeof(u32)); /* _PSE_PW_D_ID */
        if (st->podl_admin_state > 0)
                len += nla_total_size(sizeof(u32)); /* _PODL_PSE_ADMIN_STATE */
        if (st->podl_pw_status > 0)
                len += nla_total_size(sizeof(u32)); /* _PODL_PSE_PW_D_STATUS */
        if (st->c33_admin_state > 0)
                len += nla_total_size(sizeof(u32)); /* _C33_PSE_ADMIN_STATE */
        if (st->c33_pw_status > 0)
                len += nla_total_size(sizeof(u32)); /* _C33_PSE_PW_D_STATUS */
        if (st->c33_pw_class > 0)
                len += nla_total_size(sizeof(u32)); /* _C33_PSE_PW_CLASS */
        if (st->c33_actual_pw > 0)
                len += nla_total_size(sizeof(u32)); /* _C33_PSE_ACTUAL_PW */
        if (st->c33_ext_state_info.c33_pse_ext_state > 0) {
                len += nla_total_size(sizeof(u32)); /* _C33_PSE_EXT_STATE */
                if (st->c33_ext_state_info.__c33_pse_ext_substate > 0)
                        /* _C33_PSE_EXT_SUBSTATE */
                        len += nla_total_size(sizeof(u32));
        }
        if (st->c33_avail_pw_limit > 0)
                /* _C33_AVAIL_PSE_PW_LIMIT */
                len += nla_total_size(sizeof(u32));
        if (st->c33_pw_limit_nb_ranges > 0)
                /* _C33_PSE_PW_LIMIT_RANGES */
                len += st->c33_pw_limit_nb_ranges *
                       (nla_total_size(0) +
                        nla_total_size(sizeof(u32)) * 2);
        if (st->prio_max)
                /* _PSE_PRIO_MAX + _PSE_PRIO */
                len += nla_total_size(sizeof(u32)) * 2;

        return len;
}

static int pse_put_pw_limit_ranges(struct sk_buff *skb,
                                   const struct ethtool_pse_control_status *st)
{
        const struct ethtool_c33_pse_pw_limit_range *pw_limit_ranges;
        int i;

        pw_limit_ranges = st->c33_pw_limit_ranges;
        for (i = 0; i < st->c33_pw_limit_nb_ranges; i++) {
                struct nlattr *nest;

                nest = nla_nest_start(skb, ETHTOOL_A_C33_PSE_PW_LIMIT_RANGES);
                if (!nest)
                        return -EMSGSIZE;

                if (nla_put_u32(skb, ETHTOOL_A_C33_PSE_PW_LIMIT_MIN,
                                pw_limit_ranges->min) ||
                    nla_put_u32(skb, ETHTOOL_A_C33_PSE_PW_LIMIT_MAX,
                                pw_limit_ranges->max)) {
                        nla_nest_cancel(skb, nest);
                        return -EMSGSIZE;
                }
                nla_nest_end(skb, nest);
                pw_limit_ranges++;
        }

        return 0;
}

static int pse_fill_reply(struct sk_buff *skb,
                          const struct ethnl_req_info *req_base,
                          const struct ethnl_reply_data *reply_base)
{
        const struct pse_reply_data *data = PSE_REPDATA(reply_base);
        const struct ethtool_pse_control_status *st = &data->status;

        if (st->pw_d_id &&
            nla_put_u32(skb, ETHTOOL_A_PSE_PW_D_ID,
                        st->pw_d_id))
                return -EMSGSIZE;

        if (st->podl_admin_state > 0 &&
            nla_put_u32(skb, ETHTOOL_A_PODL_PSE_ADMIN_STATE,
                        st->podl_admin_state))
                return -EMSGSIZE;

        if (st->podl_pw_status > 0 &&
            nla_put_u32(skb, ETHTOOL_A_PODL_PSE_PW_D_STATUS,
                        st->podl_pw_status))
                return -EMSGSIZE;

        if (st->c33_admin_state > 0 &&
            nla_put_u32(skb, ETHTOOL_A_C33_PSE_ADMIN_STATE,
                        st->c33_admin_state))
                return -EMSGSIZE;

        if (st->c33_pw_status > 0 &&
            nla_put_u32(skb, ETHTOOL_A_C33_PSE_PW_D_STATUS,
                        st->c33_pw_status))
                return -EMSGSIZE;

        if (st->c33_pw_class > 0 &&
            nla_put_u32(skb, ETHTOOL_A_C33_PSE_PW_CLASS,
                        st->c33_pw_class))
                return -EMSGSIZE;

        if (st->c33_actual_pw > 0 &&
            nla_put_u32(skb, ETHTOOL_A_C33_PSE_ACTUAL_PW,
                        st->c33_actual_pw))
                return -EMSGSIZE;

        if (st->c33_ext_state_info.c33_pse_ext_state > 0) {
                if (nla_put_u32(skb, ETHTOOL_A_C33_PSE_EXT_STATE,
                                st->c33_ext_state_info.c33_pse_ext_state))
                        return -EMSGSIZE;

                if (st->c33_ext_state_info.__c33_pse_ext_substate > 0 &&
                    nla_put_u32(skb, ETHTOOL_A_C33_PSE_EXT_SUBSTATE,
                                st->c33_ext_state_info.__c33_pse_ext_substate))
                        return -EMSGSIZE;
        }

        if (st->c33_avail_pw_limit > 0 &&
            nla_put_u32(skb, ETHTOOL_A_C33_PSE_AVAIL_PW_LIMIT,
                        st->c33_avail_pw_limit))
                return -EMSGSIZE;

        if (st->c33_pw_limit_nb_ranges > 0 &&
            pse_put_pw_limit_ranges(skb, st))
                return -EMSGSIZE;

        if (st->prio_max &&
            (nla_put_u32(skb, ETHTOOL_A_PSE_PRIO_MAX, st->prio_max) ||
             nla_put_u32(skb, ETHTOOL_A_PSE_PRIO, st->prio)))
                return -EMSGSIZE;

        return 0;
}

static void pse_cleanup_data(struct ethnl_reply_data *reply_base)
{
        const struct pse_reply_data *data = PSE_REPDATA(reply_base);

        kfree(data->status.c33_pw_limit_ranges);
}

/* PSE_SET */

const struct nla_policy ethnl_pse_set_policy[ETHTOOL_A_PSE_MAX + 1] = {
        [ETHTOOL_A_PSE_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy_phy),
        [ETHTOOL_A_PODL_PSE_ADMIN_CONTROL] =
                NLA_POLICY_RANGE(NLA_U32, ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED,
                                 ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED),
        [ETHTOOL_A_C33_PSE_ADMIN_CONTROL] =
                NLA_POLICY_RANGE(NLA_U32, ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED,
                                 ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED),
        [ETHTOOL_A_C33_PSE_AVAIL_PW_LIMIT] = { .type = NLA_U32 },
        [ETHTOOL_A_PSE_PRIO] = { .type = NLA_U32 },
};

static int
ethnl_set_pse_validate(struct phy_device *phydev, struct genl_info *info)
{
        struct nlattr **tb = info->attrs;

        if (IS_ERR_OR_NULL(phydev)) {
                NL_SET_ERR_MSG(info->extack, "No PHY is attached");
                return -EOPNOTSUPP;
        }

        if (!phydev->psec) {
                NL_SET_ERR_MSG(info->extack, "No PSE is attached");
                return -EOPNOTSUPP;
        }

        if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL] &&
            !pse_has_podl(phydev->psec)) {
                NL_SET_ERR_MSG_ATTR(info->extack,
                                    tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL],
                                    "setting PoDL PSE admin control not supported");
                return -EOPNOTSUPP;
        }
        if (tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL] &&
            !pse_has_c33(phydev->psec)) {
                NL_SET_ERR_MSG_ATTR(info->extack,
                                    tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL],
                                    "setting C33 PSE admin control not supported");
                return -EOPNOTSUPP;
        }

        return 0;
}

static int
ethnl_set_pse(struct ethnl_req_info *req_info, struct genl_info *info)
{
        struct nlattr **tb = info->attrs;
        struct phy_device *phydev;
        int ret;

        phydev = ethnl_req_get_phydev(req_info, tb, ETHTOOL_A_PSE_HEADER,
                                      info->extack);
        ret = ethnl_set_pse_validate(phydev, info);
        if (ret)
                return ret;

        if (tb[ETHTOOL_A_PSE_PRIO]) {
                unsigned int prio;

                prio = nla_get_u32(tb[ETHTOOL_A_PSE_PRIO]);
                ret = pse_ethtool_set_prio(phydev->psec, info->extack, prio);
                if (ret)
                        return ret;
        }

        if (tb[ETHTOOL_A_C33_PSE_AVAIL_PW_LIMIT]) {
                unsigned int pw_limit;

                pw_limit = nla_get_u32(tb[ETHTOOL_A_C33_PSE_AVAIL_PW_LIMIT]);
                ret = pse_ethtool_set_pw_limit(phydev->psec, info->extack,
                                               pw_limit);
                if (ret)
                        return ret;
        }

        /* These values are already validated by the ethnl_pse_set_policy */
        if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL] ||
            tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]) {
                struct pse_control_config config = {};

                if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL])
                        config.podl_admin_control = nla_get_u32(tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL]);
                if (tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL])
                        config.c33_admin_control = nla_get_u32(tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]);

                /* pse_ethtool_set_config() will do nothing if the config
                 * is zero
                 */
                ret = pse_ethtool_set_config(phydev->psec, info->extack,
                                             &config);
                if (ret)
                        return ret;
        }

        /* Return errno or zero - PSE has no notification */
        return ret;
}

const struct ethnl_request_ops ethnl_pse_request_ops = {
        .request_cmd            = ETHTOOL_MSG_PSE_GET,
        .reply_cmd              = ETHTOOL_MSG_PSE_GET_REPLY,
        .hdr_attr               = ETHTOOL_A_PSE_HEADER,
        .req_info_size          = sizeof(struct pse_req_info),
        .reply_data_size        = sizeof(struct pse_reply_data),

        .prepare_data           = pse_prepare_data,
        .reply_size             = pse_reply_size,
        .fill_reply             = pse_fill_reply,
        .cleanup_data           = pse_cleanup_data,

        .set                    = ethnl_set_pse,
        /* PSE has no notification */
};

void ethnl_pse_send_ntf(struct net_device *netdev, unsigned long notifs)
{
        void *reply_payload;
        struct sk_buff *skb;
        int reply_len;
        int ret;

        ASSERT_RTNL();

        if (!netdev || !notifs)
                return;

        reply_len = ethnl_reply_header_size() +
                    nla_total_size(sizeof(u32)); /* _PSE_NTF_EVENTS */

        skb = genlmsg_new(reply_len, GFP_KERNEL);
        if (!skb)
                return;

        reply_payload = ethnl_bcastmsg_put(skb, ETHTOOL_MSG_PSE_NTF);
        if (!reply_payload)
                goto err_skb;

        ret = ethnl_fill_reply_header(skb, netdev, ETHTOOL_A_PSE_NTF_HEADER);
        if (ret < 0)
                goto err_skb;

        if (nla_put_uint(skb, ETHTOOL_A_PSE_NTF_EVENTS, notifs))
                goto err_skb;

        genlmsg_end(skb, reply_payload);
        ethnl_multicast(skb, netdev);
        return;

err_skb:
        nlmsg_free(skb);
}
EXPORT_SYMBOL_GPL(ethnl_pse_send_ntf);