1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * USB Power Delivery Vendor Defined Message (VDM) support code.
4 *
5 * Copyright 2023 Google LLC
6 * Author: Prashant Malani <pmalani@chromium.org>
7 */
8
9#include <linux/module.h>
10#include <linux/platform_data/cros_ec_commands.h>
11#include <linux/usb/pd_vdo.h>
12
13#include "cros_ec_typec.h"
14#include "cros_typec_vdm.h"
15
16/*
17 * Retrieves pending VDM attention messages from the EC and forwards them to the altmode driver
18 * based on SVID.
19 */
20void cros_typec_handle_vdm_attention(struct cros_typec_data *typec, int port_num)
21{
22 struct ec_response_typec_vdm_response resp;
23 struct ec_params_typec_vdm_response req = {
24 .port = port_num,
25 };
26 struct typec_altmode *amode;
27 u16 svid;
28 u32 hdr;
29 int ret;
30
31 do {
32 ret = cros_ec_cmd(ec_dev: typec->ec, version: 0, EC_CMD_TYPEC_VDM_RESPONSE, outdata: &req,
33 outsize: sizeof(req), indata: &resp, insize: sizeof(resp));
34 if (ret < 0) {
35 dev_warn(typec->dev, "Failed VDM response fetch, port: %d\n", port_num);
36 return;
37 }
38
39 hdr = resp.vdm_response[0];
40 svid = PD_VDO_VID(hdr);
41 dev_dbg(typec->dev, "Received VDM Attention header: %x, port: %d\n", hdr, port_num);
42
43 amode = typec_match_altmode(altmodes: typec->ports[port_num]->port_altmode,
44 n: CROS_EC_ALTMODE_MAX, svid, PD_VDO_OPOS(hdr));
45 if (!amode) {
46 dev_err(typec->dev,
47 "Received VDM for unregistered altmode (SVID:%x), port: %d\n",
48 svid, port_num);
49 return;
50 }
51
52 typec_altmode_attention(altmode: amode, vdo: resp.vdm_attention[1]);
53 } while (resp.vdm_attention_left);
54}
55
56/*
57 * Retrieves a VDM response from the EC and forwards it to the altmode driver based on SVID.
58 */
59void cros_typec_handle_vdm_response(struct cros_typec_data *typec, int port_num)
60{
61 struct ec_response_typec_vdm_response resp;
62 struct ec_params_typec_vdm_response req = {
63 .port = port_num,
64 };
65 struct typec_altmode *amode;
66 u16 svid;
67 u32 hdr;
68 int ret;
69
70 ret = cros_ec_cmd(ec_dev: typec->ec, version: 0, EC_CMD_TYPEC_VDM_RESPONSE, outdata: &req,
71 outsize: sizeof(req), indata: &resp, insize: sizeof(resp));
72 if (ret < 0) {
73 dev_warn(typec->dev, "Failed VDM response fetch, port: %d\n", port_num);
74 return;
75 }
76
77 hdr = resp.vdm_response[0];
78 svid = PD_VDO_VID(hdr);
79 dev_dbg(typec->dev, "Received VDM header: %x, port: %d\n", hdr, port_num);
80
81 amode = typec_match_altmode(altmodes: typec->ports[port_num]->port_altmode, n: CROS_EC_ALTMODE_MAX,
82 svid, PD_VDO_OPOS(hdr));
83 if (!amode) {
84 dev_err(typec->dev, "Received VDM for unregistered altmode (SVID:%x), port: %d\n",
85 svid, port_num);
86 return;
87 }
88
89 ret = typec_altmode_vdm(altmode: amode, header: hdr, vdo: &resp.vdm_response[1], count: resp.vdm_data_objects);
90 if (ret)
91 dev_err(typec->dev, "Failed to forward VDM to altmode (SVID:%x), port: %d\n",
92 svid, port_num);
93}
94
95static int cros_typec_port_amode_enter(struct typec_altmode *amode, u32 *vdo)
96{
97 struct cros_typec_port *port = typec_altmode_get_drvdata(altmode: amode);
98 struct ec_params_typec_control req = {
99 .port = port->port_num,
100 .command = TYPEC_CONTROL_COMMAND_SEND_VDM_REQ,
101 };
102 struct typec_vdm_req vdm_req = {};
103 u32 hdr;
104
105 hdr = VDO(amode->svid, 1, SVDM_VER_2_0, CMD_ENTER_MODE);
106 hdr |= VDO_OPOS(amode->mode);
107
108 vdm_req.vdm_data[0] = hdr;
109 vdm_req.vdm_data_objects = 1;
110 vdm_req.partner_type = TYPEC_PARTNER_SOP;
111 req.vdm_req_params = vdm_req;
112
113 dev_dbg(port->typec_data->dev, "Sending EnterMode VDM, hdr: %x, port: %d\n",
114 hdr, port->port_num);
115
116 return cros_ec_cmd(ec_dev: port->typec_data->ec, version: 0, EC_CMD_TYPEC_CONTROL, outdata: &req,
117 outsize: sizeof(req), NULL, insize: 0);
118}
119
120static int cros_typec_port_amode_vdm(struct typec_altmode *amode, const u32 hdr,
121 const u32 *vdo, int cnt)
122{
123 struct cros_typec_port *port = typec_altmode_get_drvdata(altmode: amode);
124 struct ec_params_typec_control req = {
125 .port = port->port_num,
126 .command = TYPEC_CONTROL_COMMAND_SEND_VDM_REQ,
127 };
128 struct typec_vdm_req vdm_req = {};
129 int i;
130
131 vdm_req.vdm_data[0] = hdr;
132 vdm_req.vdm_data_objects = cnt;
133 for (i = 1; i < cnt; i++)
134 vdm_req.vdm_data[i] = vdo[i-1];
135 vdm_req.partner_type = TYPEC_PARTNER_SOP;
136 req.vdm_req_params = vdm_req;
137
138 dev_dbg(port->typec_data->dev, "Sending VDM, hdr: %x, num_objects: %d, port: %d\n",
139 hdr, cnt, port->port_num);
140
141 return cros_ec_cmd(ec_dev: port->typec_data->ec, version: 0, EC_CMD_TYPEC_CONTROL, outdata: &req,
142 outsize: sizeof(req), NULL, insize: 0);
143}
144
145const struct typec_altmode_ops port_amode_ops = {
146 .enter = cros_typec_port_amode_enter,
147 .vdm = cros_typec_port_amode_vdm,
148};
149

source code of linux/drivers/platform/chrome/cros_typec_vdm.c