diff options
| -rw-r--r-- | drivers/watchdog/mei_wdt.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c index 32e3e1d55ef3..e7e3f144f2b0 100644 --- a/drivers/watchdog/mei_wdt.c +++ b/drivers/watchdog/mei_wdt.c @@ -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; |