mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 18:14:07 +08:00
platform/chrome: cros_ec: Add EC host command support using rpmsg
Add EC host command support through rpmsg. Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
This commit is contained in:
parent
9e2b0e0be6
commit
2de89fd989
@ -59,6 +59,18 @@ config CROS_EC_I2C
|
||||
a checksum. Failing accesses will be retried three times to
|
||||
improve reliability.
|
||||
|
||||
config CROS_EC_RPMSG
|
||||
tristate "ChromeOS Embedded Controller (rpmsg)"
|
||||
depends on MFD_CROS_EC && RPMSG && OF
|
||||
help
|
||||
If you say Y here, you get support for talking to the ChromeOS EC
|
||||
through rpmsg. This uses a simple byte-level protocol with a
|
||||
checksum. Also since there's no addition EC-to-host interrupt, this
|
||||
use a byte in message to distinguish host event from host command.
|
||||
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called cros_ec_rpmsg.
|
||||
|
||||
config CROS_EC_SPI
|
||||
tristate "ChromeOS Embedded Controller (SPI)"
|
||||
depends on MFD_CROS_EC && SPI
|
||||
|
@ -4,6 +4,7 @@ obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o
|
||||
obj-$(CONFIG_CHROMEOS_PSTORE) += chromeos_pstore.o
|
||||
obj-$(CONFIG_CHROMEOS_TBMC) += chromeos_tbmc.o
|
||||
obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o
|
||||
obj-$(CONFIG_CROS_EC_RPMSG) += cros_ec_rpmsg.o
|
||||
obj-$(CONFIG_CROS_EC_SPI) += cros_ec_spi.o
|
||||
cros_ec_lpcs-objs := cros_ec_lpc.o cros_ec_lpc_reg.o
|
||||
cros_ec_lpcs-$(CONFIG_CROS_EC_LPC_MEC) += cros_ec_lpc_mec.o
|
||||
|
258
drivers/platform/chrome/cros_ec_rpmsg.c
Normal file
258
drivers/platform/chrome/cros_ec_rpmsg.c
Normal file
@ -0,0 +1,258 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
//
|
||||
// Copyright 2018 Google LLC.
|
||||
|
||||
#include <linux/completion.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mfd/cros_ec.h>
|
||||
#include <linux/mfd/cros_ec_commands.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/rpmsg.h>
|
||||
#include <linux/slab.h>
|
||||
|
||||
#define EC_MSG_TIMEOUT_MS 200
|
||||
#define HOST_COMMAND_MARK 1
|
||||
#define HOST_EVENT_MARK 2
|
||||
|
||||
/**
|
||||
* struct cros_ec_rpmsg_response - rpmsg message format from from EC.
|
||||
*
|
||||
* @type: The type of message, should be either HOST_COMMAND_MARK or
|
||||
* HOST_EVENT_MARK, representing that the message is a response to
|
||||
* host command, or a host event.
|
||||
* @data: ec_host_response for host command.
|
||||
*/
|
||||
struct cros_ec_rpmsg_response {
|
||||
u8 type;
|
||||
u8 data[] __aligned(4);
|
||||
};
|
||||
|
||||
/**
|
||||
* struct cros_ec_rpmsg - information about a EC over rpmsg.
|
||||
*
|
||||
* @rpdev: rpmsg device we are connected to
|
||||
* @xfer_ack: completion for host command transfer.
|
||||
* @host_event_work: Work struct for pending host event.
|
||||
*/
|
||||
struct cros_ec_rpmsg {
|
||||
struct rpmsg_device *rpdev;
|
||||
struct completion xfer_ack;
|
||||
struct work_struct host_event_work;
|
||||
};
|
||||
|
||||
/**
|
||||
* cros_ec_cmd_xfer_rpmsg - Transfer a message over rpmsg and receive the reply
|
||||
*
|
||||
* @ec_dev: ChromeOS EC device
|
||||
* @ec_msg: Message to transfer
|
||||
*
|
||||
* This is only used for old EC proto version, and is not supported for this
|
||||
* driver.
|
||||
*
|
||||
* Return: -EINVAL
|
||||
*/
|
||||
static int cros_ec_cmd_xfer_rpmsg(struct cros_ec_device *ec_dev,
|
||||
struct cros_ec_command *ec_msg)
|
||||
{
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/**
|
||||
* cros_ec_pkt_xfer_rpmsg - Transfer a packet over rpmsg and receive the reply
|
||||
*
|
||||
* @ec_dev: ChromeOS EC device
|
||||
* @ec_msg: Message to transfer
|
||||
*
|
||||
* Return: number of bytes of the reply on success or negative error code.
|
||||
*/
|
||||
static int cros_ec_pkt_xfer_rpmsg(struct cros_ec_device *ec_dev,
|
||||
struct cros_ec_command *ec_msg)
|
||||
{
|
||||
struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv;
|
||||
struct rpmsg_device *rpdev = ec_rpmsg->rpdev;
|
||||
struct ec_host_response *response;
|
||||
unsigned long timeout;
|
||||
int len;
|
||||
int ret;
|
||||
u8 sum;
|
||||
int i;
|
||||
|
||||
ec_msg->result = 0;
|
||||
len = cros_ec_prepare_tx(ec_dev, ec_msg);
|
||||
dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
|
||||
|
||||
reinit_completion(&ec_rpmsg->xfer_ack);
|
||||
ret = rpmsg_send(rpdev->ept, ec_dev->dout, len);
|
||||
if (ret) {
|
||||
dev_err(ec_dev->dev, "rpmsg send failed\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
timeout = msecs_to_jiffies(EC_MSG_TIMEOUT_MS);
|
||||
ret = wait_for_completion_timeout(&ec_rpmsg->xfer_ack, timeout);
|
||||
if (!ret) {
|
||||
dev_err(ec_dev->dev, "rpmsg send timeout\n");
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* check response error code */
|
||||
response = (struct ec_host_response *)ec_dev->din;
|
||||
ec_msg->result = response->result;
|
||||
|
||||
ret = cros_ec_check_result(ec_dev, ec_msg);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
if (response->data_len > ec_msg->insize) {
|
||||
dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",
|
||||
response->data_len, ec_msg->insize);
|
||||
ret = -EMSGSIZE;
|
||||
goto exit;
|
||||
}
|
||||
|
||||
/* copy response packet payload and compute checksum */
|
||||
memcpy(ec_msg->data, ec_dev->din + sizeof(*response),
|
||||
response->data_len);
|
||||
|
||||
sum = 0;
|
||||
for (i = 0; i < sizeof(*response) + response->data_len; i++)
|
||||
sum += ec_dev->din[i];
|
||||
|
||||
if (sum) {
|
||||
dev_err(ec_dev->dev, "bad packet checksum, calculated %x\n",
|
||||
sum);
|
||||
ret = -EBADMSG;
|
||||
goto exit;
|
||||
}
|
||||
|
||||
ret = response->data_len;
|
||||
exit:
|
||||
if (ec_msg->command == EC_CMD_REBOOT_EC)
|
||||
msleep(EC_REBOOT_DELAY_MS);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void
|
||||
cros_ec_rpmsg_host_event_function(struct work_struct *host_event_work)
|
||||
{
|
||||
struct cros_ec_rpmsg *ec_rpmsg = container_of(host_event_work,
|
||||
struct cros_ec_rpmsg,
|
||||
host_event_work);
|
||||
struct cros_ec_device *ec_dev = dev_get_drvdata(&ec_rpmsg->rpdev->dev);
|
||||
bool wake_event = true;
|
||||
int ret;
|
||||
|
||||
ret = cros_ec_get_next_event(ec_dev, &wake_event);
|
||||
|
||||
/*
|
||||
* Signal only if wake host events or any interrupt if
|
||||
* cros_ec_get_next_event() returned an error (default value for
|
||||
* wake_event is true)
|
||||
*/
|
||||
if (wake_event && device_may_wakeup(ec_dev->dev))
|
||||
pm_wakeup_event(ec_dev->dev, 0);
|
||||
|
||||
if (ret > 0)
|
||||
blocking_notifier_call_chain(&ec_dev->event_notifier,
|
||||
0, ec_dev);
|
||||
}
|
||||
|
||||
static int cros_ec_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
|
||||
int len, void *priv, u32 src)
|
||||
{
|
||||
struct cros_ec_device *ec_dev = dev_get_drvdata(&rpdev->dev);
|
||||
struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv;
|
||||
struct cros_ec_rpmsg_response *resp;
|
||||
|
||||
if (!len) {
|
||||
dev_warn(ec_dev->dev, "rpmsg received empty response");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
resp = data;
|
||||
len -= offsetof(struct cros_ec_rpmsg_response, data);
|
||||
if (resp->type == HOST_COMMAND_MARK) {
|
||||
if (len > ec_dev->din_size) {
|
||||
dev_warn(ec_dev->dev,
|
||||
"received length %d > din_size %d, truncating",
|
||||
len, ec_dev->din_size);
|
||||
len = ec_dev->din_size;
|
||||
}
|
||||
|
||||
memcpy(ec_dev->din, resp->data, len);
|
||||
complete(&ec_rpmsg->xfer_ack);
|
||||
} else if (resp->type == HOST_EVENT_MARK) {
|
||||
schedule_work(&ec_rpmsg->host_event_work);
|
||||
} else {
|
||||
dev_warn(ec_dev->dev, "rpmsg received invalid type = %d",
|
||||
resp->type);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int cros_ec_rpmsg_probe(struct rpmsg_device *rpdev)
|
||||
{
|
||||
struct device *dev = &rpdev->dev;
|
||||
struct cros_ec_rpmsg *ec_rpmsg;
|
||||
struct cros_ec_device *ec_dev;
|
||||
|
||||
ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
|
||||
if (!ec_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
ec_rpmsg = devm_kzalloc(dev, sizeof(*ec_rpmsg), GFP_KERNEL);
|
||||
if (!ec_rpmsg)
|
||||
return -ENOMEM;
|
||||
|
||||
ec_dev->dev = dev;
|
||||
ec_dev->priv = ec_rpmsg;
|
||||
ec_dev->cmd_xfer = cros_ec_cmd_xfer_rpmsg;
|
||||
ec_dev->pkt_xfer = cros_ec_pkt_xfer_rpmsg;
|
||||
ec_dev->phys_name = dev_name(&rpdev->dev);
|
||||
ec_dev->din_size = sizeof(struct ec_host_response) +
|
||||
sizeof(struct ec_response_get_protocol_info);
|
||||
ec_dev->dout_size = sizeof(struct ec_host_request);
|
||||
dev_set_drvdata(dev, ec_dev);
|
||||
|
||||
ec_rpmsg->rpdev = rpdev;
|
||||
init_completion(&ec_rpmsg->xfer_ack);
|
||||
INIT_WORK(&ec_rpmsg->host_event_work,
|
||||
cros_ec_rpmsg_host_event_function);
|
||||
|
||||
return cros_ec_register(ec_dev);
|
||||
}
|
||||
|
||||
static void cros_ec_rpmsg_remove(struct rpmsg_device *rpdev)
|
||||
{
|
||||
struct cros_ec_device *ec_dev = dev_get_drvdata(&rpdev->dev);
|
||||
struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv;
|
||||
|
||||
cancel_work_sync(&ec_rpmsg->host_event_work);
|
||||
}
|
||||
|
||||
static const struct of_device_id cros_ec_rpmsg_of_match[] = {
|
||||
{ .compatible = "google,cros-ec-rpmsg", },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, cros_ec_rpmsg_of_match);
|
||||
|
||||
static struct rpmsg_driver cros_ec_driver_rpmsg = {
|
||||
.drv = {
|
||||
.name = "cros-ec-rpmsg",
|
||||
.of_match_table = cros_ec_rpmsg_of_match,
|
||||
},
|
||||
.probe = cros_ec_rpmsg_probe,
|
||||
.remove = cros_ec_rpmsg_remove,
|
||||
.callback = cros_ec_rpmsg_callback,
|
||||
};
|
||||
|
||||
module_rpmsg_driver(cros_ec_driver_rpmsg);
|
||||
|
||||
MODULE_LICENSE("GPL v2");
|
||||
MODULE_DESCRIPTION("ChromeOS EC multi function device (rpmsg)");
|
Loading…
Reference in New Issue
Block a user