android_kernel_xiaomi_sm8350/drivers/soc/qcom/altmode-glink.c
Subbaraman Narayanamurthy f9823cba3c soc: qcom: altmode-glink: add ipc logging support
Add ipc logging support so that the essential log information can
be stored and looked upon especially when dynamic_debug log
filter is not set. This is useful for debugging.

Change-Id: I33c8eb1733ab1ecc541abb86f4f351ce9c8ff394
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
2021-03-29 15:46:31 -07:00

810 lines
20 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2020-2021 The Linux Foundation. All rights reserved.
*/
#define pr_fmt(fmt) "altmode-glink: %s: " fmt, __func__
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/idr.h>
#include <linux/ipc_logging.h>
#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/soc/qcom/altmode-glink.h>
#include <linux/soc/qcom/pmic_glink.h>
#define MSG_OWNER_USBC_PAN 32780
#define MSG_TYPE_REQ_RESP 1
#define NOTIFY_PAYLOAD_SIZE 16
#define USBC_WRITE_BUFFER_SIZE 8
#define USBC_CMD_WRITE_REQ 0x15
#define USBC_NOTIFY_IND 0x16
#define MAX_NUM_PORTS 4
#define NUM_LOG_PAGES 10
#define IDR_KEY_GEN(svid, ind) (((svid) << 8) | (ind))
#define IDR_KEY(client) \
IDR_KEY_GEN((client)->data.svid, (client)->port_index)
#define altmode_dbg(fmt, ...) \
do { \
ipc_log_string(altmode_ipc_log, fmt, ##__VA_ARGS__); \
pr_debug(fmt, ##__VA_ARGS__); \
} while (0)
struct usbc_notify_ind_msg {
struct pmic_glink_hdr hdr;
u8 payload[NOTIFY_PAYLOAD_SIZE];
u32 reserved;
};
struct usbc_write_buffer_req_msg {
struct pmic_glink_hdr hdr;
u8 buf[USBC_WRITE_BUFFER_SIZE];
u32 reserved;
};
/**
* struct altmode_dev
* Definition of an altmode device.
*
* @dev: Altmode parent device for all client devices
* @pgclient: PMIC GLINK client to talk to remote subsystem
* @client_idr: idr list for altmode clients
* @client_lock: mutex protecting changes to client_idr
* @d_node: Linked list node to string together multiple amdev's
* @client_list: Linked list head keeping track of this device's clients
* @pan_en_sent: Flag to ensure PAN Enable msg is sent only once
* @send_pan_en_work: To schedule the sending of the PAN Enable message
* @send_pan_ack_work: To schedule the sending of the PAN Ack message
* @debugfs_dir: Dentry for debugfs directory "altmode"
* @response_received: To detect remote subsystem response failures
* @ack_port_index: Port index to ack for a nonexistent client
*/
struct altmode_dev {
struct device *dev;
struct pmic_glink_client *pgclient;
struct idr client_idr;
struct mutex client_lock;
struct list_head d_node;
struct list_head client_list;
atomic_t pan_en_sent;
struct delayed_work send_pan_en_work;
struct delayed_work send_pan_ack_work;
struct dentry *debugfs_dir;
struct completion response_received;
u8 ack_port_index;
};
/**
* struct altmode_client
* Definition of a client of an altmode device.
*
* @amdev: Parent altmode device of this client
* @data: Supplied by client driver during registration
* @c_node: Linked list node for parent altmode device's client list
* @port_index: Type-C port index assigned by remote subystem
*
* Note: The following members are for internal use only, clients should not
* use them.
*
* @client_cb_work: Work to run client callback
* @msg: Latest notify msg stashed to be retrieved in cb_work
*/
struct altmode_client {
struct altmode_dev *amdev;
struct altmode_client_data data;
struct list_head c_node;
u8 port_index;
struct work_struct client_cb_work;
u8 msg[NOTIFY_PAYLOAD_SIZE];
};
/**
* struct probe_notify_node
* Linked list node to keep track of altmode clients who, by design,
* register with the altmode framework before altmode probes.
*
* @node: Linked list node for probe_notify_list
* @amdev_node: device_node of the altmode device of the client
* @cb: Client's probe completion callback function
* @priv: Pointer to client's driver data struct
*/
struct probe_notify_node {
struct list_head node;
struct device_node *amdev_node;
void (*cb)(void *priv);
void *priv;
};
/**
* struct list_head probe_notify_list
* List of altmode clients that register to get notified upon probe
* completion.
*/
static LIST_HEAD(probe_notify_list);
static DEFINE_MUTEX(notify_lock);
static void altmode_send_pan_ack(struct work_struct *work);
static void *altmode_ipc_log;
static struct altmode_dev *to_altmode_device(struct device_node *amdev_node)
{
struct platform_device *altmode_pdev;
altmode_pdev = of_find_device_by_node(amdev_node);
if (altmode_pdev)
return platform_get_drvdata(altmode_pdev);
return NULL;
}
#define ALTMODE_WAIT_MS 1000
static int altmode_write(struct altmode_dev *amdev, void *data, size_t len)
{
int rc;
reinit_completion(&amdev->response_received);
rc = pmic_glink_write(amdev->pgclient, data, len);
if (!rc) {
rc = wait_for_completion_timeout(&amdev->response_received,
msecs_to_jiffies(ALTMODE_WAIT_MS));
rc = rc ? 0 : -ETIMEDOUT;
}
if (rc)
pr_err("Error in sending message: %d\n", rc);
return rc;
}
static int __altmode_send_data(struct altmode_dev *amdev, void *data,
size_t len)
{
struct usbc_write_buffer_req_msg msg = { { 0 } };
if (len > sizeof(msg.buf)) {
pr_err("len %zu exceeds msg buf's size: %zu\n",
len, USBC_WRITE_BUFFER_SIZE);
return -EINVAL;
}
msg.hdr.owner = MSG_OWNER_USBC_PAN;
msg.hdr.type = MSG_TYPE_REQ_RESP;
msg.hdr.opcode = USBC_CMD_WRITE_REQ;
memcpy(msg.buf, data, len);
return altmode_write(amdev, &msg, sizeof(msg));
}
/**
* altmode_register_notifier()
* Register to be notified when altmode device probes.
*
* @client_dev: Client device pointer
* @cb: Callback function to execute when altmode device of
* interest probes successfully
* @priv: Client's private data which is passed back when cb() is
* called
*
* Returns: 0 upon success, negative upon errors.
*/
int altmode_register_notifier(struct device *client_dev, void (*cb)(void *),
void *priv)
{
int rc;
struct probe_notify_node *notify_node;
struct device_node *amdev_node;
struct of_phandle_args pargs;
struct altmode_dev *amdev;
if (!client_dev || !cb || !priv)
return -EINVAL;
rc = of_parse_phandle_with_args(client_dev->of_node,
"qcom,altmode-dev", "#altmode-cells", 0, &pargs);
if (rc) {
dev_err(client_dev, "Error parsing qcom,altmode-dev property: %d\n",
rc);
return rc;
}
amdev_node = pargs.np;
mutex_lock(&notify_lock);
amdev = to_altmode_device(amdev_node);
if (amdev) {
/*
* If altmode device has probed already, notify
* immediately.
*/
of_node_put(amdev_node);
cb(priv);
} else {
notify_node = kzalloc(sizeof(*notify_node), GFP_KERNEL);
if (!notify_node) {
mutex_unlock(&notify_lock);
return -ENOMEM;
}
notify_node->cb = cb;
notify_node->priv = priv;
notify_node->amdev_node = amdev_node;
list_add(&notify_node->node, &probe_notify_list);
}
mutex_unlock(&notify_lock);
return 0;
}
EXPORT_SYMBOL(altmode_register_notifier);
/**
* altmode_deregister_notifier()
* Deregister probe completion notifier.
*
* @client_dev: Client device pointer
* @priv: Client's private data
*
* Returns: 0 upon success, negative upon errors.
*/
int altmode_deregister_notifier(struct device *client_dev, void *priv)
{
int rc;
struct device_node *amdev_node;
struct probe_notify_node *pos, *tmp;
struct of_phandle_args pargs;
if (!client_dev)
return -EINVAL;
rc = of_parse_phandle_with_args(client_dev->of_node,
"qcom,altmode-dev", "#altmode-cells", 0, &pargs);
if (rc) {
dev_err(client_dev, "Error parsing qcom,altmode-dev property: %d\n",
rc);
return rc;
}
amdev_node = pargs.np;
mutex_lock(&notify_lock);
list_for_each_entry_safe(pos, tmp, &probe_notify_list, node) {
if (pos->amdev_node == amdev_node && pos->priv == priv) {
of_node_put(pos->amdev_node);
list_del(&pos->node);
kfree(pos);
break;
}
}
mutex_unlock(&notify_lock);
of_node_put(amdev_node);
return 0;
}
EXPORT_SYMBOL(altmode_deregister_notifier);
/**
* altmode_send_data()
* Send data from altmode client to remote subsystem.
*
* @client: Parent altmode device of this client
* @data: Data to be sent
* @len: Length in bytes of the data to be sent
*
* Returns: 0 upon success, -EINVAL if len exceeds message buffer's
* capacity, and other negative error codes as appropriate.
*/
int altmode_send_data(struct altmode_client *client, void *data,
size_t len)
{
struct altmode_dev *amdev = client->amdev;
return __altmode_send_data(amdev, data, len);
}
EXPORT_SYMBOL(altmode_send_data);
static void client_cb_work(struct work_struct *work)
{
struct altmode_client *amclient = container_of(work,
struct altmode_client, client_cb_work);
amclient->data.callback(amclient->data.priv, amclient->msg,
sizeof(amclient->msg));
}
/**
* altmode_register_client()
* Register with altmode to receive PMIC GLINK messages from remote
* subsystem.
*
* @client_dev: Client device pointer
* @client_data: Details identifying altmode client uniquely
*
* Returns: Valid altmode client pointer upon success, ERR_PTRs
* upon errors.
*
* Notes: client_data should contain a unique SVID.
*/
struct altmode_client *altmode_register_client(struct device *client_dev,
const struct altmode_client_data *client_data)
{
int rc, key;
struct altmode_dev *amdev;
struct of_phandle_args pargs;
struct device_node *amdev_node;
struct altmode_client *amclient;
if (!client_dev || !client_data)
return ERR_PTR(-EINVAL);
if (!client_data->name || !client_data->priv || !client_data->callback
|| !client_data->svid)
return ERR_PTR(-EINVAL);
rc = of_parse_phandle_with_args(client_dev->of_node,
"qcom,altmode-dev", "#altmode-cells", 0, &pargs);
if (rc) {
dev_err(client_dev, "Error parsing qcom,altmode-dev property: %d\n",
rc);
return ERR_PTR(rc);
}
if (pargs.args_count != 1) {
dev_err(client_dev, "Error in port_index specification\n");
return ERR_PTR(-EINVAL);
}
if (pargs.args[0] >= MAX_NUM_PORTS) {
dev_err(client_dev, "Invalid port_index: %d, max is %d\n",
pargs.args[0], MAX_NUM_PORTS - 1);
return ERR_PTR(-EINVAL);
}
amdev_node = pargs.np;
amdev = to_altmode_device(amdev_node);
of_node_put(amdev_node);
if (!amdev)
return ERR_PTR(-EPROBE_DEFER);
amclient = kzalloc(sizeof(*amclient), GFP_KERNEL);
if (!amclient)
return ERR_PTR(-ENOMEM);
amclient->amdev = amdev;
amclient->port_index = pargs.args[0];
amclient->data.svid = client_data->svid;
amclient->data.priv = client_data->priv;
amclient->data.callback = client_data->callback;
INIT_WORK(&amclient->client_cb_work, client_cb_work);
amclient->data.name = kstrdup(client_data->name, GFP_KERNEL);
if (!amclient->data.name) {
kfree(amclient);
return ERR_PTR(-ENOMEM);
}
mutex_lock(&amdev->client_lock);
key = IDR_KEY(amclient);
rc = idr_alloc(&amdev->client_idr, amclient, key, key + 1, GFP_KERNEL);
if (rc < 0) {
pr_err("Error in allocating idr for client %s: %d\n",
client_data->name, rc);
mutex_unlock(&amdev->client_lock);
kfree(amclient->data.name);
kfree(amclient);
return ERR_PTR(rc);
}
list_add(&amclient->c_node, &amdev->client_list);
mutex_unlock(&amdev->client_lock);
if (!atomic_read(&amdev->pan_en_sent))
schedule_delayed_work(&amdev->send_pan_en_work,
msecs_to_jiffies(20));
return amclient;
}
EXPORT_SYMBOL(altmode_register_client);
/**
* altmode_deregister_client()
* Deregister altmode client to stop receiving PMIC GLINK messages
* specific to its SVID from remote subsystem.
*
* @client: Client returned by altmode_register_client()
*
* Returns: 0 upon success, negative upon errors.
*
* Notes: This does not stop the transmission of the messages by
* the remote subsystem - only the reception of them by
* the client.
*/
int altmode_deregister_client(struct altmode_client *client)
{
struct altmode_dev *amdev;
struct altmode_client *pos, *tmp;
if (!client || !client->amdev)
return -ENODEV;
amdev = client->amdev;
cancel_work_sync(&client->client_cb_work);
mutex_lock(&amdev->client_lock);
idr_remove(&amdev->client_idr, IDR_KEY(client));
list_for_each_entry_safe(pos, tmp, &amdev->client_list, c_node) {
if (pos == client)
list_del(&pos->c_node);
}
mutex_unlock(&amdev->client_lock);
kfree(client->data.name);
kfree(client);
return 0;
}
EXPORT_SYMBOL(altmode_deregister_client);
static void altmode_send_pan_en(struct work_struct *work)
{
int rc;
u32 enable_msg = ALTMODE_PAN_EN;
struct altmode_dev *amdev = container_of(work, struct altmode_dev,
send_pan_en_work.work);
rc = __altmode_send_data(amdev, &enable_msg, sizeof(enable_msg));
if (rc < 0) {
pr_err("Failed to send PAN EN: %d\n", rc);
return;
}
atomic_set(&amdev->pan_en_sent, 1);
altmode_dbg("Sent PAN EN\n");
}
static int altmode_send_ack(struct altmode_dev *amdev, u8 port_index)
{
int rc;
struct altmode_pan_ack_msg ack;
ack.cmd_type = ALTMODE_PAN_ACK;
ack.port_index = port_index;
rc = __altmode_send_data(amdev, &ack, sizeof(ack));
if (rc < 0) {
pr_err("port %u: Failed to send PAN ACK: %d\n", port_index, rc);
return rc;
}
altmode_dbg("port %u: Sent PAN ACK\n", port_index);
return rc;
}
static void altmode_state_cb(void *priv, enum pmic_glink_state state)
{
struct altmode_dev *amdev = priv;
altmode_dbg("state: %d\n", state);
switch (state) {
case PMIC_GLINK_STATE_DOWN:
/* As of now, nothing to do */
break;
case PMIC_GLINK_STATE_UP:
mutex_lock(&amdev->client_lock);
if (!list_empty(&amdev->client_list))
schedule_delayed_work(&amdev->send_pan_en_work,
msecs_to_jiffies(20));
mutex_unlock(&amdev->client_lock);
break;
default:
return;
}
}
static void altmode_send_pan_ack(struct work_struct *work)
{
struct altmode_dev *amdev = container_of(work, struct altmode_dev,
send_pan_ack_work.work);
altmode_send_ack(amdev, amdev->ack_port_index);
}
#define USBC_NOTIFY_IND_MASK GENMASK(7, 0)
#define GET_OP(opcode) (opcode & USBC_NOTIFY_IND_MASK)
#define GET_SVID(opcode) (opcode >> 16)
static int altmode_callback(void *priv, void *data, size_t len)
{
u16 svid, op;
struct usbc_notify_ind_msg *notify_msg;
struct pmic_glink_hdr *hdr = data;
struct altmode_dev *amdev = priv;
struct altmode_client *amclient;
u8 port_index;
altmode_dbg("len: %zu owner: %u type: %u opcode %04x\n", len, hdr->owner,
hdr->type, hdr->opcode);
/*
* For DisplayPort alt mode, the hdr->opcode is designed as follows:
*
* hdr->opcode = (svid << 16) | USBC_NOTIFY_IND
*/
op = GET_OP(hdr->opcode);
svid = GET_SVID(hdr->opcode);
switch (op) {
case USBC_CMD_WRITE_REQ:
complete(&amdev->response_received);
break;
case USBC_NOTIFY_IND:
if (len != sizeof(*notify_msg)) {
altmode_dbg("Expected length %u, got: %zu\n",
sizeof(*notify_msg), len);
return -EINVAL;
}
notify_msg = data;
port_index = notify_msg->payload[0];
mutex_lock(&amdev->client_lock);
amclient = idr_find(&amdev->client_idr, IDR_KEY_GEN(svid,
port_index));
mutex_unlock(&amdev->client_lock);
if (!amclient) {
altmode_dbg("No client associated with SVID %#x port %u\n",
svid, port_index);
amdev->ack_port_index = port_index;
schedule_delayed_work(&amdev->send_pan_ack_work,
msecs_to_jiffies(20));
return 0;
}
altmode_dbg("Payload: %*ph\n", NOTIFY_PAYLOAD_SIZE,
notify_msg->payload);
cancel_work_sync(&amclient->client_cb_work);
memcpy(&amclient->msg, notify_msg->payload,
sizeof(amclient->msg));
schedule_work(&amclient->client_cb_work);
break;
default:
break;
}
return 0;
}
static void altmode_notify_clients(struct altmode_dev *amdev)
{
struct altmode_dev *pos_amdev;
struct probe_notify_node *pos, *tmp;
mutex_lock(&notify_lock);
list_for_each_entry_safe(pos, tmp, &probe_notify_list, node) {
pos_amdev = to_altmode_device(pos->amdev_node);
if (!pos_amdev)
continue;
if (pos_amdev == amdev) {
pos->cb(pos->priv);
of_node_put(pos->amdev_node);
list_del(&pos->node);
kfree(pos);
}
}
mutex_unlock(&notify_lock);
}
#ifdef CONFIG_QTI_PMIC_GLINK_CLIENT_DEBUG
static int pan_en_write(void *data, u64 val)
{
struct altmode_dev *amdev = data;
schedule_delayed_work(&amdev->send_pan_en_work,
msecs_to_jiffies(20));
return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(pan_en_fops, NULL, pan_en_write, "%llu\n");
static int send_ack_write(void *data, u64 val)
{
int rc;
struct altmode_dev *amdev = data;
struct altmode_pan_ack_msg ack;
if (val >= MAX_NUM_PORTS)
return -EINVAL;
ack.cmd_type = ALTMODE_PAN_ACK;
ack.port_index = val;
rc = __altmode_send_data(amdev, &ack, sizeof(ack));
if (rc < 0) {
dev_err(amdev->dev, "port %d: Failed sending PAN ACK: %llu\n",
val, rc);
return rc;
}
dev_dbg(amdev->dev, "port %llu: Sent PAN ACK via debugfs\n", val);
return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(send_ack_fops, NULL, send_ack_write, "%llu\n");
static int altmode_setup_debugfs(struct altmode_dev *amdev)
{
int rc;
struct dentry *am_dir, *file;
am_dir = debugfs_create_dir("altmode", NULL);
if (IS_ERR(am_dir)) {
rc = PTR_ERR(am_dir);
dev_err(amdev->dev, "Failed to create altmode directory: %d\n",
rc);
return rc;
}
file = debugfs_create_file_unsafe("send_pan_en", 0200, am_dir, amdev,
&pan_en_fops);
if (IS_ERR(file)) {
rc = PTR_ERR(file);
dev_err(amdev->dev, "Failed to create send_pan_en: %d\n", rc);
goto error;
}
file = debugfs_create_file_unsafe("send_pan_ack", 0200, am_dir,
amdev, &send_ack_fops);
if (IS_ERR(file)) {
rc = PTR_ERR(file);
dev_err(amdev->dev, "Failed to create send_pan_ack: %d\n", rc);
goto error;
}
amdev->debugfs_dir = am_dir;
return 0;
error:
debugfs_remove_recursive(am_dir);
return rc;
}
#else
static int altmode_setup_debugfs(struct altmode_dev *amdev)
{
return 0;
}
#endif
static int altmode_probe(struct platform_device *pdev)
{
int rc;
struct altmode_dev *amdev;
struct pmic_glink_client_data pgclient_data = { };
struct device *dev = &pdev->dev;
amdev = devm_kzalloc(&pdev->dev, sizeof(*amdev), GFP_KERNEL);
if (!amdev)
return -ENOMEM;
amdev->dev = dev;
mutex_init(&amdev->client_lock);
idr_init(&amdev->client_idr);
init_completion(&amdev->response_received);
INIT_DELAYED_WORK(&amdev->send_pan_en_work, altmode_send_pan_en);
INIT_DELAYED_WORK(&amdev->send_pan_ack_work, altmode_send_pan_ack);
INIT_LIST_HEAD(&amdev->d_node);
INIT_LIST_HEAD(&amdev->client_list);
pgclient_data.id = MSG_OWNER_USBC_PAN;
pgclient_data.name = "altmode";
pgclient_data.msg_cb = altmode_callback;
pgclient_data.priv = amdev;
pgclient_data.state_cb = altmode_state_cb;
amdev->pgclient = pmic_glink_register_client(amdev->dev,
&pgclient_data);
if (IS_ERR(amdev->pgclient)) {
rc = PTR_ERR(amdev->pgclient);
if (rc != -EPROBE_DEFER)
dev_err(dev, "Error in pmic_glink registration: %d\n",
rc);
goto error_register;
}
platform_set_drvdata(pdev, amdev);
rc = altmode_setup_debugfs(amdev);
if (rc < 0) {
dev_err(amdev->dev, "Failed to create debugfs: %d\n", rc);
goto unreg_pmic_glink;
}
altmode_ipc_log = ipc_log_context_create(NUM_LOG_PAGES, "altmode", 0);
if (!altmode_ipc_log)
dev_warn(dev, "Error in creating ipc_log_context\n");
altmode_notify_clients(amdev);
return 0;
unreg_pmic_glink:
pmic_glink_unregister_client(amdev->pgclient);
error_register:
idr_destroy(&amdev->client_idr);
return rc;
}
static int altmode_remove(struct platform_device *pdev)
{
int rc;
struct altmode_dev *amdev = platform_get_drvdata(pdev);
struct altmode_client *client, *tmp;
struct probe_notify_node *npos, *ntmp;
debugfs_remove_recursive(amdev->debugfs_dir);
cancel_delayed_work_sync(&amdev->send_pan_en_work);
cancel_delayed_work_sync(&amdev->send_pan_ack_work);
idr_destroy(&amdev->client_idr);
atomic_set(&amdev->pan_en_sent, 0);
mutex_lock(&notify_lock);
list_for_each_entry_safe(npos, ntmp, &probe_notify_list, node) {
of_node_put(npos->amdev_node);
list_del(&npos->node);
kfree(npos);
}
mutex_unlock(&notify_lock);
mutex_lock(&amdev->client_lock);
list_for_each_entry_safe(client, tmp, &amdev->client_list, c_node)
list_del(&client->c_node);
mutex_unlock(&amdev->client_lock);
ipc_log_context_destroy(altmode_ipc_log);
altmode_ipc_log = NULL;
rc = pmic_glink_unregister_client(amdev->pgclient);
if (rc < 0)
dev_err(amdev->dev, "Error in pmic_glink de-registration: %d\n",
rc);
return rc;
}
static const struct of_device_id altmode_match_table[] = {
{ .compatible = "qcom,altmode-glink" },
{},
};
static struct platform_driver altmode_driver = {
.driver = {
.name = "altmode-glink",
.of_match_table = altmode_match_table,
},
.probe = altmode_probe,
.remove = altmode_remove,
};
module_platform_driver(altmode_driver);
MODULE_DESCRIPTION("QTI Type-C Alt Mode over GLINK");
MODULE_LICENSE("GPL v2");