1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Regulator event over netlink
4 *
5 * Author: Naresh Solanki <Naresh.Solanki@9elements.com>
6 */
7
8#include <regulator/regulator.h>
9#include <net/netlink.h>
10#include <net/genetlink.h>
11#include <linux/atomic.h>
12
13#include "regnl.h"
14
15static atomic_t reg_event_seqnum = ATOMIC_INIT(0);
16
17static const struct genl_multicast_group reg_event_mcgrps[] = {
18 { .name = REG_GENL_MCAST_GROUP_NAME, },
19};
20
21static struct genl_family reg_event_genl_family __ro_after_init = {
22 .module = THIS_MODULE,
23 .name = REG_GENL_FAMILY_NAME,
24 .version = REG_GENL_VERSION,
25 .maxattr = REG_GENL_ATTR_MAX,
26 .mcgrps = reg_event_mcgrps,
27 .n_mcgrps = ARRAY_SIZE(reg_event_mcgrps),
28};
29
30int reg_generate_netlink_event(const char *reg_name, u64 event)
31{
32 struct sk_buff *skb;
33 struct nlattr *attr;
34 struct reg_genl_event *edata;
35 void *msg_header;
36 int size;
37
38 /* allocate memory */
39 size = nla_total_size(payload: sizeof(struct reg_genl_event)) +
40 nla_total_size(payload: 0);
41
42 skb = genlmsg_new(payload: size, GFP_ATOMIC);
43 if (!skb)
44 return -ENOMEM;
45
46 /* add the genetlink message header */
47 msg_header = genlmsg_put(skb, portid: 0, seq: atomic_inc_return(v: &reg_event_seqnum),
48 family: &reg_event_genl_family, flags: 0, cmd: REG_GENL_CMD_EVENT);
49 if (!msg_header) {
50 nlmsg_free(skb);
51 return -ENOMEM;
52 }
53
54 /* fill the data */
55 attr = nla_reserve(skb, attrtype: REG_GENL_ATTR_EVENT, attrlen: sizeof(struct reg_genl_event));
56 if (!attr) {
57 nlmsg_free(skb);
58 return -EINVAL;
59 }
60
61 edata = nla_data(nla: attr);
62 memset(edata, 0, sizeof(struct reg_genl_event));
63
64 strscpy(edata->reg_name, reg_name, sizeof(edata->reg_name));
65 edata->event = event;
66
67 /* send multicast genetlink message */
68 genlmsg_end(skb, hdr: msg_header);
69 size = genlmsg_multicast(family: &reg_event_genl_family, skb, portid: 0, group: 0, GFP_ATOMIC);
70
71 return size;
72}
73
74static int __init reg_event_genetlink_init(void)
75{
76 return genl_register_family(family: &reg_event_genl_family);
77}
78
79static int __init reg_event_init(void)
80{
81 int error;
82
83 /* create genetlink for acpi event */
84 error = reg_event_genetlink_init();
85 if (error)
86 pr_warn("Failed to create genetlink family for reg event\n");
87
88 return 0;
89}
90
91fs_initcall(reg_event_init);
92

source code of linux/drivers/regulator/event.c