/*
* ChromeOS EC multi-function device
*
* Copyright (C) 2012 Google, Inc
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* The ChromeOS EC multi function device is used to mux all the requests
* to the EC device for its multiple features: keyboard controller,
* battery charging and regulator control, firmware update.
*/
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>
int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
struct cros_ec_msg *msg)
{
uint8_t *out;
int csum, i;
BUG_ON(msg->out_len > EC_HOST_PARAM_SIZE);
out = ec_dev->dout;
out[0] = EC_CMD_VERSION0 + msg->version;
out[1] = msg->cmd;
out[2] = msg->out_len;
csum = out[0] + out[1] + out[2];
for (i = 0; i < msg->out_len; i++)
csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->out_buf[i];
out[EC_MSG_TX_HEADER_BYTES + msg->out_len] = (uint8_t)(csum & 0xff);
return EC_MSG_TX_PROTO_BYTES + msg->out_len;
}
EXPORT_SYMBOL(cros_ec_prepare_tx);
static int cros_ec_command_sendrecv(struct cros_ec_device *ec_dev,
uint16_t cmd, void *out_buf, int out_len,
void *in_buf, int in_len)
{
struct cros_ec_msg msg;
msg.version = cmd >> 8;
msg.cmd = cmd & 0xff;
msg.out_buf = out_buf;
msg.out_len = out_len;
msg.in_buf = in_buf;
msg.in_len = in_len;
return ec_dev->command_xfer(ec_dev, &msg);
}
static int cros_ec_command_recv(struct cros_ec_device *ec_dev,
uint16_t cmd, void *buf, int buf_len)
{
return cros_ec_command_sendrecv(ec_dev, cmd, NULL, 0, buf, buf_len);
}
static int cros_ec_command_send(struct cros_ec_device *ec_dev,
uint16_t cmd, void *buf, int buf_len)
{
return cros_ec_command_sendrecv(ec_dev, cmd, buf, buf_len, NULL, 0);
}
static irqreturn_t ec_irq_thread(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
if (device_may_wakeup(ec_dev->dev))
pm_wakeup_event(ec_dev->dev, 0);
blocking_notifier_call_chain(&ec_dev->event_notifier, 1, ec_dev);
return IRQ_HANDLED;
}
static struct mfd_cell cros_devs[] = {
{
.name = "cros-ec-keyb",
.id = 1,
.of_compatible = "google,cros-ec-keyb",
},
};
int cros_ec_register(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int err = 0;
BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
ec_dev->command_send = cros_ec_command_send;
ec_dev->command_recv = cros_ec_command_recv;
ec_dev->command_sendrecv = cros_ec_command_sendrecv;
if (ec_dev->din_size) {
ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
if (!ec_dev->din)
return -ENOMEM;
}
if (ec_dev->dout_size) {
ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
if (!ec_dev->dout)
return -ENOMEM;
}
if (!ec_dev->irq) {
dev_dbg(dev, "no valid IRQ: %d\n", ec_dev->irq);
return err;
}
err = request_threaded_irq(ec_dev->irq, NULL, ec_irq_thread,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"chromeos-ec", ec_dev);
if (err) {
dev_err(dev, "request irq %d: error %d\n", ec_dev->irq, err);
return err;
}
err = mfd_add_devices(dev, 0, cros_devs,
ARRAY_SIZE(cros_devs),
NULL, ec_dev->irq, NULL);
if (err) {
dev_err(dev, "failed to add mfd devices\n");
goto fail_mfd;
}
dev_info(dev, "Chrome EC (%s)\n", ec_dev->name);
return 0;
fail_mfd:
free_irq(ec_dev->irq, ec_dev);
return err;
}
EXPORT_SYMBOL(cros_ec_register);
int cros_ec_remove(struct cros_ec_device *ec_dev)
{
mfd_remove_devices(ec_dev->dev);
free_irq(ec_dev->irq, ec_dev);
return 0;
}
EXPORT_SYMBOL(cros_ec_remove);
#ifdef CONFIG_PM_SLEEP
int cros_ec_suspend(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
if (device_may_wakeup(dev))
ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
disable_irq(ec_dev->irq);
ec_dev->was_wake_device = ec_dev->wake_enabled;
return 0;
}
EXPORT_SYMBOL(cros_ec_suspend);
int cros_ec_resume(struct cros_ec_device *ec_dev)
{
enable_irq(ec_dev->irq);
if (ec_dev->wake_enabled) {
disable_irq_wake(ec_dev->irq);
ec_dev->wake_enabled = 0;
}
return 0;
}
EXPORT_SYMBOL(cros_ec_resume);
#endif
