From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752815AbbLUXTK (ORCPT ); Mon, 21 Dec 2015 18:19:10 -0500 Received: from mga04.intel.com ([192.55.52.120]:43043 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752748AbbLUXTG (ORCPT ); Mon, 21 Dec 2015 18:19:06 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,461,1444719600"; d="scan'208";a="876306382" From: Tomas Winkler To: Greg Kroah-Hartman , Wim Van Sebroeck Cc: Alexander Usyskin , Guenter Roeck , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, Tomas Winkler Subject: [char-misc-next v3 4/8] watchdog: mei_wdt: add status debugfs entry Date: Tue, 22 Dec 2015 01:17:57 +0200 Message-Id: <1450739881-3923-5-git-send-email-tomas.winkler@intel.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1450739881-3923-1-git-send-email-tomas.winkler@intel.com> References: <1450739881-3923-1-git-send-email-tomas.winkler@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add entry for dumping current watchdog internal state Signed-off-by: Tomas Winkler --- V2: new in the series V3: rebase drivers/watchdog/mei_wdt.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c index 5b28a1e95ac1..ab9aec218d69 100644 --- a/drivers/watchdog/mei_wdt.c +++ b/drivers/watchdog/mei_wdt.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -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; /** @@ -76,6 +95,8 @@ struct mei_wdt_dev { * @cldev: mei watchdog client device * @state: watchdog internal state * @timeout: watchdog current timeout + * + * @dbgfs_dir: debugfs dir entry */ struct mei_wdt { struct mei_wdt_dev *mwd; @@ -83,6 +104,10 @@ 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 */ }; /* @@ -387,6 +412,65 @@ static int mei_wdt_register(struct mei_wdt *wdt) return 0; } +#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[32]; + ssize_t pos = 0; + + pos += scnprintf(buf + pos, bufsz - pos, "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) +{ + if (!wdt->dbgfs_dir) + return; + 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) { @@ -414,6 +498,8 @@ static int mei_wdt_probe(struct mei_cl_device *cldev, if (ret) goto err_disable; + dbgfs_register(wdt); + return 0; err_disable: @@ -433,6 +519,8 @@ static int mei_wdt_remove(struct mei_cl_device *cldev) mei_cldev_disable(cldev); + dbgfs_unregister(wdt); + kfree(wdt); return 0; -- 2.4.3