mfd: cros_ec: add debugfs, console log file (e8626459) · Commits · 戴 / test

drivers/platform/chrome/Makefile

+2 −1

Original line number	Diff line number	Diff line
		@@ -2,7 +2,8 @@
		obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o
		obj-$(CONFIG_CHROMEOS_PSTORE) += chromeos_pstore.o
		cros_ec_devs-objs := cros_ec_dev.o cros_ec_sysfs.o \
		cros_ec_lightbar.o cros_ec_vbc.o
		cros_ec_lightbar.o cros_ec_vbc.o \
		cros_ec_debugfs.o
		obj-$(CONFIG_CROS_EC_CHARDEV) += cros_ec_devs.o
		obj-$(CONFIG_CROS_EC_LPC) += cros_ec_lpc.o
		obj-$(CONFIG_CROS_EC_PROTO) += cros_ec_proto.o

drivers/platform/chrome/cros_ec_debugfs.c

0 → 100644

+347 −0

Original line number	Diff line number	Diff line
		/*
		* cros_ec_debugfs - debug logs for Chrome OS EC
		*
		* Copyright 2015 Google, Inc.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* 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.
		*
		* You should have received a copy of the GNU General Public License
		* along with this program. If not, see <http://www.gnu.org/licenses/>.
		*/

		#include <linux/circ_buf.h>
		#include <linux/debugfs.h>
		#include <linux/delay.h>
		#include <linux/fs.h>
		#include <linux/mfd/cros_ec.h>
		#include <linux/mfd/cros_ec_commands.h>
		#include <linux/mutex.h>
		#include <linux/poll.h>
		#include <linux/sched.h>
		#include <linux/slab.h>
		#include <linux/wait.h>

		#include "cros_ec_dev.h"
		#include "cros_ec_debugfs.h"

		#define LOG_SHIFT 14
		#define LOG_SIZE (1 << LOG_SHIFT)
		#define LOG_POLL_SEC 10

		#define CIRC_ADD(idx, size, value) (((idx) + (value)) & ((size) - 1))

		/* struct cros_ec_debugfs - ChromeOS EC debugging information
		*
		* @ec: EC device this debugfs information belongs to
		* @dir: dentry for debugfs files
		* @log_buffer: circular buffer for console log information
		* @read_msg: preallocated EC command and buffer to read console log
		* @log_mutex: mutex to protect circular buffer
		* @log_wq: waitqueue for log readers
		* @log_poll_work: recurring task to poll EC for new console log data
		*/
		struct cros_ec_debugfs {
		struct cros_ec_dev *ec;
		struct dentry *dir;
		struct circ_buf log_buffer;
		struct cros_ec_command *read_msg;
		struct mutex log_mutex;
		wait_queue_head_t log_wq;
		struct delayed_work log_poll_work;
		};

		/*
		* We need to make sure that the EC log buffer on the UART is large enough,
		* so that it is unlikely enough to overlow within LOG_POLL_SEC.
		*/
		static void cros_ec_console_log_work(struct work_struct *__work)
		{
		struct cros_ec_debugfs *debug_info =
		container_of(to_delayed_work(__work),
		struct cros_ec_debugfs,
		log_poll_work);
		struct cros_ec_dev *ec = debug_info->ec;
		struct circ_buf *cb = &debug_info->log_buffer;
		struct cros_ec_command snapshot_msg = {
		.command = EC_CMD_CONSOLE_SNAPSHOT + ec->cmd_offset,
		};

		struct ec_params_console_read_v1 *read_params =
		(struct ec_params_console_read_v1 *)debug_info->read_msg->data;
		uint8_t ec_buffer = (uint8_t )debug_info->read_msg->data;
		int idx;
		int buf_space;
		int ret;

		ret = cros_ec_cmd_xfer(ec->ec_dev, &snapshot_msg);
		if (ret < 0) {
		dev_err(ec->dev, "EC communication failed\n");
		goto resched;
		}
		if (snapshot_msg.result != EC_RES_SUCCESS) {
		dev_err(ec->dev, "EC failed to snapshot the console log\n");
		goto resched;
		}

		/* Loop until we have read everything, or there's an error. */
		mutex_lock(&debug_info->log_mutex);
		buf_space = CIRC_SPACE(cb->head, cb->tail, LOG_SIZE);

		while (1) {
		if (!buf_space) {
		dev_info_once(ec->dev,
		"Some logs may have been dropped...\n");
		break;
		}

		memset(read_params, '\0', sizeof(*read_params));
		read_params->subcmd = CONSOLE_READ_RECENT;
		ret = cros_ec_cmd_xfer(ec->ec_dev, debug_info->read_msg);
		if (ret < 0) {
		dev_err(ec->dev, "EC communication failed\n");
		break;
		}
		if (debug_info->read_msg->result != EC_RES_SUCCESS) {
		dev_err(ec->dev,
		"EC failed to read the console log\n");
		break;
		}

		/* If the buffer is empty, we're done here. */
		if (ret == 0 \|\| ec_buffer[0] == '\0')
		break;

		idx = 0;
		while (idx < ret && ec_buffer[idx] != '\0' && buf_space > 0) {
		cb->buf[cb->head] = ec_buffer[idx];
		cb->head = CIRC_ADD(cb->head, LOG_SIZE, 1);
		idx++;
		buf_space--;
		}

		wake_up(&debug_info->log_wq);
		}

		mutex_unlock(&debug_info->log_mutex);

		resched:
		schedule_delayed_work(&debug_info->log_poll_work,
		msecs_to_jiffies(LOG_POLL_SEC * 1000));
		}

		static int cros_ec_console_log_open(struct inode inode, struct file file)
		{
		file->private_data = inode->i_private;

		return nonseekable_open(inode, file);
		}

		static ssize_t cros_ec_console_log_read(struct file file, char __user buf,
		size_t count, loff_t *ppos)
		{
		struct cros_ec_debugfs *debug_info = file->private_data;
		struct circ_buf *cb = &debug_info->log_buffer;
		ssize_t ret;

		mutex_lock(&debug_info->log_mutex);

		while (!CIRC_CNT(cb->head, cb->tail, LOG_SIZE)) {
		if (file->f_flags & O_NONBLOCK) {
		ret = -EAGAIN;
		goto error;
		}

		mutex_unlock(&debug_info->log_mutex);

		ret = wait_event_interruptible(debug_info->log_wq,
		CIRC_CNT(cb->head, cb->tail, LOG_SIZE));
		if (ret < 0)
		return ret;

		mutex_lock(&debug_info->log_mutex);
		}

		/* Only copy until the end of the circular buffer, and let userspace
		* retry to get the rest of the data.
		*/
		ret = min_t(size_t, CIRC_CNT_TO_END(cb->head, cb->tail, LOG_SIZE),
		count);

		if (copy_to_user(buf, cb->buf + cb->tail, ret)) {
		ret = -EFAULT;
		goto error;
		}

		cb->tail = CIRC_ADD(cb->tail, LOG_SIZE, ret);

		error:
		mutex_unlock(&debug_info->log_mutex);
		return ret;
		}

		static unsigned int cros_ec_console_log_poll(struct file *file,
		poll_table *wait)
		{
		struct cros_ec_debugfs *debug_info = file->private_data;
		unsigned int mask = 0;

		poll_wait(file, &debug_info->log_wq, wait);

		mutex_lock(&debug_info->log_mutex);
		if (CIRC_CNT(debug_info->log_buffer.head,
		debug_info->log_buffer.tail,
		LOG_SIZE))
		mask \|= POLLIN \| POLLRDNORM;
		mutex_unlock(&debug_info->log_mutex);

		return mask;
		}

		static int cros_ec_console_log_release(struct inode inode, struct file file)
		{
		return 0;
		}

		const struct file_operations cros_ec_console_log_fops = {
		.owner = THIS_MODULE,
		.open = cros_ec_console_log_open,
		.read = cros_ec_console_log_read,
		.llseek = no_llseek,
		.poll = cros_ec_console_log_poll,
		.release = cros_ec_console_log_release,
		};

		static int ec_read_version_supported(struct cros_ec_dev *ec)
		{
		struct ec_params_get_cmd_versions_v1 *params;
		struct ec_response_get_cmd_versions *response;
		int ret;

		struct cros_ec_command *msg;

		msg = kzalloc(sizeof(*msg) + max(sizeof(params), sizeof(response)),
		GFP_KERNEL);
		if (!msg)
		return 0;

		msg->command = EC_CMD_GET_CMD_VERSIONS + ec->cmd_offset;
		msg->outsize = sizeof(params);
		msg->insize = sizeof(response);

		params = (struct ec_params_get_cmd_versions_v1 *)msg->data;
		params->cmd = EC_CMD_CONSOLE_READ;
		response = (struct ec_response_get_cmd_versions *)msg->data;

		ret = cros_ec_cmd_xfer(ec->ec_dev, msg) >= 0 &&
		msg->result == EC_RES_SUCCESS &&
		(response->version_mask & EC_VER_MASK(1));

		kfree(msg);

		return ret;
		}

		static int cros_ec_create_console_log(struct cros_ec_debugfs *debug_info)
		{
		struct cros_ec_dev *ec = debug_info->ec;
		char *buf;
		int read_params_size;
		int read_response_size;

		if (!ec_read_version_supported(ec)) {
		dev_warn(ec->dev,
		"device does not support reading the console log\n");
		return 0;
		}

		buf = devm_kzalloc(ec->dev, LOG_SIZE, GFP_KERNEL);
		if (!buf)
		return -ENOMEM;

		read_params_size = sizeof(struct ec_params_console_read_v1);
		read_response_size = ec->ec_dev->max_response;
		debug_info->read_msg = devm_kzalloc(ec->dev,
		sizeof(*debug_info->read_msg) +
		max(read_params_size, read_response_size), GFP_KERNEL);
		if (!debug_info->read_msg)
		return -ENOMEM;

		debug_info->read_msg->version = 1;
		debug_info->read_msg->command = EC_CMD_CONSOLE_READ + ec->cmd_offset;
		debug_info->read_msg->outsize = read_params_size;
		debug_info->read_msg->insize = read_response_size;

		debug_info->log_buffer.buf = buf;
		debug_info->log_buffer.head = 0;
		debug_info->log_buffer.tail = 0;

		mutex_init(&debug_info->log_mutex);
		init_waitqueue_head(&debug_info->log_wq);

		if (!debugfs_create_file("console_log",
		S_IFREG \| S_IRUGO,
		debug_info->dir,
		debug_info,
		&cros_ec_console_log_fops))
		return -ENOMEM;

		INIT_DELAYED_WORK(&debug_info->log_poll_work,
		cros_ec_console_log_work);
		schedule_delayed_work(&debug_info->log_poll_work, 0);

		return 0;
		}

		static void cros_ec_cleanup_console_log(struct cros_ec_debugfs *debug_info)
		{
		if (debug_info->log_buffer.buf) {
		cancel_delayed_work_sync(&debug_info->log_poll_work);
		mutex_destroy(&debug_info->log_mutex);
		}
		}

		int cros_ec_debugfs_init(struct cros_ec_dev *ec)
		{
		struct cros_ec_platform *ec_platform = dev_get_platdata(ec->dev);
		const char *name = ec_platform->ec_name;
		struct cros_ec_debugfs *debug_info;
		int ret;

		debug_info = devm_kzalloc(ec->dev, sizeof(*debug_info), GFP_KERNEL);
		if (!debug_info)
		return -ENOMEM;

		debug_info->ec = ec;
		debug_info->dir = debugfs_create_dir(name, NULL);
		if (!debug_info->dir)
		return -ENOMEM;

		ret = cros_ec_create_console_log(debug_info);
		if (ret)
		goto remove_debugfs;

		ec->debug_info = debug_info;

		return 0;

		remove_debugfs:
		debugfs_remove_recursive(debug_info->dir);
		return ret;
		}

		void cros_ec_debugfs_remove(struct cros_ec_dev *ec)
		{
		if (!ec->debug_info)
		return;

		debugfs_remove_recursive(ec->debug_info->dir);
		cros_ec_cleanup_console_log(ec->debug_info);
		}

drivers/platform/chrome/cros_ec_debugfs.h

0 → 100644

+27 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright 2015 Google, Inc.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* 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.
		*
		* You should have received a copy of the GNU General Public License
		* along with this program. If not, see <http://www.gnu.org/licenses/>.
		*/

		#ifndef _DRV_CROS_EC_DEBUGFS_H_
		#define _DRV_CROS_EC_DEBUGFS_H_

		#include "cros_ec_dev.h"

		/* debugfs stuff */
		int cros_ec_debugfs_init(struct cros_ec_dev *ec);
		void cros_ec_debugfs_remove(struct cros_ec_dev *ec);

		#endif /* _DRV_CROS_EC_DEBUGFS_H_ */

drivers/platform/chrome/cros_ec_dev.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@
		#include <linux/slab.h>
		#include <linux/uaccess.h>

		#include "cros_ec_debugfs.h"
		#include "cros_ec_dev.h"

		/* Device variables */
		@@ -427,6 +428,9 @@ static int ec_device_probe(struct platform_device *pdev)
		goto failed;
		}

		if (cros_ec_debugfs_init(ec))
		dev_warn(dev, "failed to create debugfs directory\n");

		/* check whether this EC is a sensor hub. */
		if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
		cros_ec_sensors_register(ec);
		@@ -441,6 +445,9 @@ failed:
		static int ec_device_remove(struct platform_device *pdev)
		{
		struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);

		cros_ec_debugfs_remove(ec);

		cdev_del(&ec->cdev);
		device_unregister(&ec->class_dev);
		return 0;

include/linux/mfd/cros_ec.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -172,6 +172,8 @@ struct cros_ec_platform {
		u16 cmd_offset;
		};

		struct cros_ec_debugfs;

		/*
		* struct cros_ec_dev - ChromeOS EC device entry point
		*
		@@ -179,6 +181,7 @@ struct cros_ec_platform {
		* @cdev: Character device structure in /dev
		* @ec_dev: cros_ec_device structure to talk to the physical device
		* @dev: pointer to the platform device
		* @debug_info: cros_ec_debugfs structure for debugging information
		* @cmd_offset: offset to apply for each command.
		*/
		struct cros_ec_dev {
		@@ -186,6 +189,7 @@ struct cros_ec_dev {
		struct cdev cdev;
		struct cros_ec_device *ec_dev;
		struct device *dev;
		struct cros_ec_debugfs *debug_info;
		u16 cmd_offset;
		u32 features[2];
		};

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