Commit c9cf20ee authored by Tomas Winkler's avatar Tomas Winkler Committed by Greg Kroah-Hartman
Browse files

watchdog: mei_wdt: add status debugfs entry 



Add entry for displaying current watchdog internal state

cat <debugfs>/mei_wdt/state
IDLE|START|RUNNING|STOPPING

Signed-off-by: default avatarTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 222818c3

drivers/watchdog/mei_wdt.c

+87 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/module.h>

#include <linux/slab.h>

#include <linux/interrupt.h>

#include <linux/debugfs.h>

#include <linux/watchdog.h>



#include <linux/uuid.h>
@@ -54,6 +55,24 @@ enum mei_wdt_state { 
	MEI_WDT_STOPPING,

};



#if IS_ENABLED(CONFIG_DEBUG_FS)

static const char *mei_wdt_state_str(enum mei_wdt_state state)

{

	switch (state) {

	case MEI_WDT_IDLE:

		return "IDLE";

	case MEI_WDT_START:

		return "START";

	case MEI_WDT_RUNNING:

		return "RUNNING";

	case MEI_WDT_STOPPING:

		return "STOPPING";

	default:

		return "unknown";

	}

}

#endif /* CONFIG_DEBUG_FS */



/**

 * struct mei_wdt - mei watchdog driver

 * @wdd: watchdog device
@@ -61,6 +80,8 @@ enum mei_wdt_state { 
 * @cldev: mei watchdog client device

 * @state: watchdog internal state

 * @timeout: watchdog current timeout

 *

 * @dbgfs_dir: debugfs dir entry

 */

struct mei_wdt {

	struct watchdog_device wdd;
@@ -68,6 +89,10 @@ struct mei_wdt { 
	struct mei_cl_device *cldev;

	enum mei_wdt_state state;

	u16 timeout;



#if IS_ENABLED(CONFIG_DEBUG_FS)

	struct dentry *dbgfs_dir;

#endif /* CONFIG_DEBUG_FS */

};



/*
@@ -310,6 +335,63 @@ static int mei_wdt_register(struct mei_wdt *wdt) 
	return ret;

}



#if IS_ENABLED(CONFIG_DEBUG_FS)



static ssize_t mei_dbgfs_read_state(struct file *file, char __user *ubuf,

				    size_t cnt, loff_t *ppos)

{

	struct mei_wdt *wdt = file->private_data;

	const size_t bufsz = 32;

	char buf[bufsz];

	ssize_t pos;



	pos = scnprintf(buf, bufsz, "state: %s\n",

			 mei_wdt_state_str(wdt->state));



	return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos);

}



static const struct file_operations dbgfs_fops_state = {

	.open = simple_open,

	.read = mei_dbgfs_read_state,

	.llseek = generic_file_llseek,

};



static void dbgfs_unregister(struct mei_wdt *wdt)

{

	debugfs_remove_recursive(wdt->dbgfs_dir);

	wdt->dbgfs_dir = NULL;

}



static int dbgfs_register(struct mei_wdt *wdt)

{

	struct dentry *dir, *f;



	dir = debugfs_create_dir(KBUILD_MODNAME, NULL);

	if (!dir)

		return -ENOMEM;



	wdt->dbgfs_dir = dir;

	f = debugfs_create_file("state", S_IRUSR, dir, wdt, &dbgfs_fops_state);

	if (!f)

		goto err;



	return 0;

err:

	dbgfs_unregister(wdt);

	return -ENODEV;

}



#else



static inline void dbgfs_unregister(struct mei_wdt *wdt) {}



static inline int dbgfs_register(struct mei_wdt *wdt)

{

	return 0;

}

#endif /* CONFIG_DEBUG_FS */



static int mei_wdt_probe(struct mei_cl_device *cldev,

			 const struct mei_cl_device_id *id)

{
@@ -337,6 +419,9 @@ static int mei_wdt_probe(struct mei_cl_device *cldev, 
	if (ret)

		goto err_disable;



	if (dbgfs_register(wdt))

		dev_warn(&cldev->dev, "cannot register debugfs\n");



	return 0;



err_disable:
@@ -356,6 +441,8 @@ static int mei_wdt_remove(struct mei_cl_device *cldev) 


	mei_cldev_disable(cldev);



	dbgfs_unregister(wdt);



	kfree(wdt);



	return 0;