/*
 * Intel MIC Platform Software Stack (MPSS)
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * 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 full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Intel MIC Coprocessor State Management (COSM) Driver
 *
 */
#include <linux/slab.h>
#include "cosm_main.h"

/*
 * A state-to-string lookup table, for exposing a human readable state
 * via sysfs. Always keep in sync with enum cosm_states
 */
const char * const cosm_state_string[] = {
	[MIC_READY] = "ready",
	[MIC_BOOTING] = "booting",
	[MIC_ONLINE] = "online",
	[MIC_SHUTTING_DOWN] = "shutting_down",
	[MIC_RESETTING] = "resetting",
	[MIC_RESET_FAILED] = "reset_failed",
};

/*
 * A shutdown-status-to-string lookup table, for exposing a human
 * readable state via sysfs. Always keep in sync with enum cosm_shutdown_status
 */
const char * const cosm_shutdown_status_string[] = {
	[MIC_NOP] = "nop",
	[MIC_CRASHED] = "crashed",
	[MIC_HALTED] = "halted",
	[MIC_POWER_OFF] = "poweroff",
	[MIC_RESTART] = "restart",
};

void cosm_set_shutdown_status(struct cosm_device *cdev, u8 shutdown_status)
{
	dev_dbg(&cdev->dev, "Shutdown Status %s -> %s\n",
		cosm_shutdown_status_string[cdev->shutdown_status],
		cosm_shutdown_status_string[shutdown_status]);
	cdev->shutdown_status = shutdown_status;
}

void cosm_set_state(struct cosm_device *cdev, u8 state)
{
	dev_dbg(&cdev->dev, "State %s -> %s\n",
		cosm_state_string[cdev->state],
		cosm_state_string[state]);
	cdev->state = state;
	sysfs_notify_dirent(cdev->state_sysfs);
}

static ssize_t
family_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	return cdev->hw_ops->family(cdev, buf);
}
static DEVICE_ATTR_RO(family);

static ssize_t
stepping_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	return cdev->hw_ops->stepping(cdev, buf);
}
static DEVICE_ATTR_RO(stepping);

static ssize_t
state_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev || cdev->state >= MIC_LAST)
		return -EINVAL;

	return scnprintf(buf, PAGE_SIZE, "%s\n",
		cosm_state_string[cdev->state]);
}

static ssize_t
state_store(struct device *dev, struct device_attribute *attr,
	    const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	int rc;

	if (!cdev)
		return -EINVAL;

	if (sysfs_streq(buf, "boot")) {
		rc = cosm_start(cdev);
		goto done;
	}
	if (sysfs_streq(buf, "reset")) {
		rc = cosm_reset(cdev);
		goto done;
	}

	if (sysfs_streq(buf, "shutdown")) {
		rc = cosm_shutdown(cdev);
		goto done;
	}
	rc = -EINVAL;
done:
	if (rc)
		count = rc;
	return count;
}
static DEVICE_ATTR_RW(state);

static ssize_t shutdown_status_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev || cdev->shutdown_status >= MIC_STATUS_LAST)
		return -EINVAL;

	return scnprintf(buf, PAGE_SIZE, "%s\n",
		cosm_shutdown_status_string[cdev->shutdown_status]);
}
static DEVICE_ATTR_RO(shutdown_status);

static ssize_t
heartbeat_enable_show(struct device *dev,
		      struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	return scnprintf(buf, PAGE_SIZE, "%d\n", cdev->sysfs_heartbeat_enable);
}

static ssize_t
heartbeat_enable_store(struct device *dev,
		       struct device_attribute *attr,
		       const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	int enable;
	int ret;

	if (!cdev)
		return -EINVAL;

	mutex_lock(&cdev->cosm_mutex);
	ret = kstrtoint(buf, 10, &enable);
	if (ret)
		goto unlock;

	cdev->sysfs_heartbeat_enable = enable;
	/* if state is not online, cdev->heartbeat_watchdog_enable is 0 */
	if (cdev->state == MIC_ONLINE)
		cdev->heartbeat_watchdog_enable = enable;
	ret = count;
unlock:
	mutex_unlock(&cdev->cosm_mutex);
	return ret;
}
static DEVICE_ATTR_RW(heartbeat_enable);

static ssize_t
cmdline_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	char *cmdline;

	if (!cdev)
		return -EINVAL;

	cmdline = cdev->cmdline;

	if (cmdline)
		return scnprintf(buf, PAGE_SIZE, "%s\n", cmdline);
	return 0;
}

static ssize_t
cmdline_store(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	mutex_lock(&cdev->cosm_mutex);
	kfree(cdev->cmdline);

	cdev->cmdline = kmalloc(count + 1, GFP_KERNEL);
	if (!cdev->cmdline) {
		count = -ENOMEM;
		goto unlock;
	}

	strncpy(cdev->cmdline, buf, count);

	if (cdev->cmdline[count - 1] == '\n')
		cdev->cmdline[count - 1] = '\0';
	else
		cdev->cmdline[count] = '\0';
unlock:
	mutex_unlock(&cdev->cosm_mutex);
	return count;
}
static DEVICE_ATTR_RW(cmdline);

static ssize_t
firmware_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	char *firmware;

	if (!cdev)
		return -EINVAL;

	firmware = cdev->firmware;

	if (firmware)
		return scnprintf(buf, PAGE_SIZE, "%s\n", firmware);
	return 0;
}

static ssize_t
firmware_store(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	mutex_lock(&cdev->cosm_mutex);
	kfree(cdev->firmware);

	cdev->firmware = kmalloc(count + 1, GFP_KERNEL);
	if (!cdev->firmware) {
		count = -ENOMEM;
		goto unlock;
	}
	strncpy(cdev->firmware, buf, count);

	if (cdev->firmware[count - 1] == '\n')
		cdev->firmware[count - 1] = '\0';
	else
		cdev->firmware[count] = '\0';
unlock:
	mutex_unlock(&cdev->cosm_mutex);
	return count;
}
static DEVICE_ATTR_RW(firmware);

static ssize_t
ramdisk_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	char *ramdisk;

	if (!cdev)
		return -EINVAL;

	ramdisk = cdev->ramdisk;

	if (ramdisk)
		return scnprintf(buf, PAGE_SIZE, "%s\n", ramdisk);
	return 0;
}

static ssize_t
ramdisk_store(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	mutex_lock(&cdev->cosm_mutex);
	kfree(cdev->ramdisk);

	cdev->ramdisk = kmalloc(count + 1, GFP_KERNEL);
	if (!cdev->ramdisk) {
		count = -ENOMEM;
		goto unlock;
	}

	strncpy(cdev->ramdisk, buf, count);

	if (cdev->ramdisk[count - 1] == '\n')
		cdev->ramdisk[count - 1] = '\0';
	else
		cdev->ramdisk[count] = '\0';
unlock:
	mutex_unlock(&cdev->cosm_mutex);
	return count;
}
static DEVICE_ATTR_RW(ramdisk);

static ssize_t
bootmode_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	char *bootmode;

	if (!cdev)
		return -EINVAL;

	bootmode = cdev->bootmode;

	if (bootmode)
		return scnprintf(buf, PAGE_SIZE, "%s\n", bootmode);
	return 0;
}

static ssize_t
bootmode_store(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	if (!sysfs_streq(buf, "linux") && !sysfs_streq(buf, "flash"))
		return -EINVAL;

	mutex_lock(&cdev->cosm_mutex);
	kfree(cdev->bootmode);

	cdev->bootmode = kmalloc(count + 1, GFP_KERNEL);
	if (!cdev->bootmode) {
		count = -ENOMEM;
		goto unlock;
	}

	strncpy(cdev->bootmode, buf, count);

	if (cdev->bootmode[count - 1] == '\n')
		cdev->bootmode[count - 1] = '\0';
	else
		cdev->bootmode[count] = '\0';
unlock:
	mutex_unlock(&cdev->cosm_mutex);
	return count;
}
static DEVICE_ATTR_RW(bootmode);

static ssize_t
log_buf_addr_show(struct device *dev, struct device_attribute *attr,
		  char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	return scnprintf(buf, PAGE_SIZE, "%p\n", cdev->log_buf_addr);
}

static ssize_t
log_buf_addr_store(struct device *dev, struct device_attribute *attr,
		   const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	int ret;
	unsigned long addr;

	if (!cdev)
		return -EINVAL;

	ret = kstrtoul(buf, 16, &addr);
	if (ret)
		goto exit;

	cdev->log_buf_addr = (void *)addr;
	ret = count;
exit:
	return ret;
}
static DEVICE_ATTR_RW(log_buf_addr);

static ssize_t
log_buf_len_show(struct device *dev, struct device_attribute *attr,
		 char *buf)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);

	if (!cdev)
		return -EINVAL;

	return scnprintf(buf, PAGE_SIZE, "%p\n", cdev->log_buf_len);
}

static ssize_t
log_buf_len_store(struct device *dev, struct device_attribute *attr,
		  const char *buf, size_t count)
{
	struct cosm_device *cdev = dev_get_drvdata(dev);
	int ret;
	unsigned long addr;

	if (!cdev)
		return -EINVAL;

	ret = kstrtoul(buf, 16, &addr);
	if (ret)
		goto exit;

	cdev->log_buf_len = (int *)addr;
	ret = count;
exit:
	return ret;
}
static DEVICE_ATTR_RW(log_buf_len);

static struct attribute *cosm_default_attrs[] = {
	&dev_attr_family.attr,
	&dev_attr_stepping.attr,
	&dev_attr_state.attr,
	&dev_attr_shutdown_status.attr,
	&dev_attr_heartbeat_enable.attr,
	&dev_attr_cmdline.attr,
	&dev_attr_firmware.attr,
	&dev_attr_ramdisk.attr,
	&dev_attr_bootmode.attr,
	&dev_attr_log_buf_addr.attr,
	&dev_attr_log_buf_len.attr,

	NULL
};

ATTRIBUTE_GROUPS(cosm_default);

void cosm_sysfs_init(struct cosm_device *cdev)
{
	cdev->attr_group = cosm_default_groups;
}