From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933186AbbLRQnH (ORCPT ); Fri, 18 Dec 2015 11:43:07 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:58289 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932264AbbLRQnE (ORCPT ); Fri, 18 Dec 2015 11:43:04 -0500 Subject: Re: [char-misc-next 4/7] watchdog: mei_wdt: add status debugfs entry To: Tomas Winkler , Greg Kroah-Hartman , Wim Van Sebroeck References: <1450363780-30008-1-git-send-email-tomas.winkler@intel.com> <1450363780-30008-5-git-send-email-tomas.winkler@intel.com> Cc: Alexander Usyskin , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org From: Guenter Roeck Message-ID: <56743795.6090700@roeck-us.net> Date: Fri, 18 Dec 2015 08:43:01 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <1450363780-30008-5-git-send-email-tomas.winkler@intel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/17/2015 06:49 AM, Tomas Winkler wrote: > Add entry for dumping current watchdog internal state > > Signed-off-by: Tomas Winkler > --- > drivers/watchdog/mei_wdt.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 84 insertions(+) > > diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c > index 3c97deb70d90..a3f1c1613c32 100644 > --- a/drivers/watchdog/mei_wdt.c > +++ b/drivers/watchdog/mei_wdt.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -54,6 +55,19 @@ 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"; Doesn't this cause checkpatch warnings ? > + } > +} > +#endif /* CONFIG_DEBUG_FS */ > + Can you move this conditional code into the other #ifdef block below ? Thanks, Guenter > /** > * struct mei_wdt - mei watchdog driver > * @wdd: watchdog device > @@ -62,6 +76,8 @@ enum mei_wdt_state { > * @state: watchdog internal state > * @cldev: mei watchdog client device > * @timeout: watchdog current timeout > + * > + * @dbgfs_dir: debugfs dir entry > */ > struct mei_wdt { > struct watchdog_device wdd; > @@ -70,6 +86,10 @@ 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 */ > }; > > /* > @@ -296,6 +316,66 @@ static void mei_wdt_ops_unref(struct watchdog_device *wdd) > kref_put(&wdt->refcnt, mei_wdt_release); > } > > +#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_deregister(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_deregister(wdt); > + return -ENODEV; > +} > + > +#else > + > +static inline void dbgfs_deregister(struct mei_wdt *wdt) {} > + > +static inline int dbgfs_register(struct mei_wdt *wdt) > +{ > + return 0; > +} > +#endif /* CONFIG_DEBUG_FS */ > + > + > static const struct watchdog_ops wd_ops = { > .owner = THIS_MODULE, > .start = mei_wdt_ops_start, > @@ -348,6 +428,8 @@ static int mei_wdt_probe(struct mei_cl_device *cldev, > if (ret) > goto err_disable; > > + dbgfs_register(wdt); > + > return 0; > > err_disable: > @@ -367,6 +449,8 @@ static int mei_wdt_remove(struct mei_cl_device *cldev) > > kref_put(&wdt->refcnt, mei_wdt_release); > > + dbgfs_deregister(wdt); > + This should probably come before the call to kref_put() since it uses wdt. > mei_cldev_disable(cldev); > > return 0; >