From patchwork Tue Nov 10 19:43:00 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Albrecht_Dre=C3=9F?= X-Patchwork-Id: 38095 X-Patchwork-Delegate: grant.likely@secretlab.ca Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from bilbo.ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id 5E2E6100F16 for ; Wed, 11 Nov 2009 09:10:51 +1100 (EST) Received: by ozlabs.org (Postfix) id 028F3B8930; Wed, 11 Nov 2009 09:10:21 +1100 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: from smtp6.netcologne.de (smtp6.netcologne.de [194.8.194.26]) by ozlabs.org (Postfix) with ESMTP id 87BCAB831B for ; Wed, 11 Nov 2009 09:10:19 +1100 (EST) Received: from antares (xdsl-78-34-235-25.netcologne.de [78.34.235.25]) by smtp6.netcologne.de (Postfix) with ESMTP id C35B22A1C00; Tue, 10 Nov 2009 20:43:00 +0100 (CET) Received: from antares (localhost [127.0.0.1]) by antares (Postfix) with ESMTPS id 89AB7BA03E; Tue, 10 Nov 2009 20:43:00 +0100 (CET) Date: Tue, 10 Nov 2009 20:43:00 +0100 From: Albrecht =?iso-8859-1?b?RHJl3w==?= Subject: [PATCH 3/3] mpc52xx/wdt: WDT uses GPT api To: Linux PPC Development , Grant Likely , devicetree-discuss@lists.ozlabs.org, Wim Van Sebroeck X-Mailer: Balsa 2.4.1 Message-Id: <1257882180.14374.3@antares> MIME-Version: 1.0 Content-Disposition: inline X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Use the MPC5200 GPT api for the WDT which drastically simplifies this file. Signed-off-by: Albrecht Dreß --- drivers/watchdog/mpc5200_wdt.c | 246 +++++++++++----------------------------- 1 files changed, 65 insertions(+), 181 deletions(-) diff --git a/drivers/watchdog/mpc5200_wdt.c b/drivers/watchdog/mpc5200_wdt.c index fa9c47c..5bb553c 100644 --- a/drivers/watchdog/mpc5200_wdt.c +++ b/drivers/watchdog/mpc5200_wdt.c @@ -2,25 +2,16 @@ #include #include #include -#include -#include #include #include #include -#define GPT_MODE_WDT (1 << 15) -#define GPT_MODE_CE (1 << 12) -#define GPT_MODE_MS_TIMER (0x4) - +#define WDT_IDENTITY "mpc5200 watchdog on GPT0" struct mpc5200_wdt { - unsigned count; /* timer ticks before watchdog kicks in */ - long ipb_freq; - struct miscdevice miscdev; - struct resource mem; - struct mpc52xx_gpt __iomem *regs; - spinlock_t io_lock; + int timeout; + struct mpc52xx_gpt_priv *timer; }; /* is_active stores wether or not the /dev/watchdog device is opened */ @@ -32,80 +23,33 @@ static unsigned long is_active; static struct mpc5200_wdt *wdt_global; -/* helper to calculate timeout in timer counts */ -static void mpc5200_wdt_set_timeout(struct mpc5200_wdt *wdt, int timeout) -{ - /* use biggest prescaler of 64k */ - wdt->count = (wdt->ipb_freq + 0xffff) / 0x10000 * timeout; - - if (wdt->count > 0xffff) - wdt->count = 0xffff; -} -/* return timeout in seconds (calculated from timer count) */ -static int mpc5200_wdt_get_timeout(struct mpc5200_wdt *wdt) -{ - return wdt->count * 0x10000 / wdt->ipb_freq; -} - - -/* watchdog operations */ -static int mpc5200_wdt_start(struct mpc5200_wdt *wdt) -{ - spin_lock(&wdt->io_lock); - /* disable */ - out_be32(&wdt->regs->mode, 0); - /* set timeout, with maximum prescaler */ - out_be32(&wdt->regs->count, 0x0 | wdt->count); - /* enable watchdog */ - out_be32(&wdt->regs->mode, GPT_MODE_CE | GPT_MODE_WDT | - GPT_MODE_MS_TIMER); - spin_unlock(&wdt->io_lock); - - return 0; -} -static int mpc5200_wdt_ping(struct mpc5200_wdt *wdt) -{ - spin_lock(&wdt->io_lock); - /* writing A5 to OCPW resets the watchdog */ - out_be32(&wdt->regs->mode, 0xA5000000 | - (0xffffff & in_be32(&wdt->regs->mode))); - spin_unlock(&wdt->io_lock); - return 0; -} -static int mpc5200_wdt_stop(struct mpc5200_wdt *wdt) -{ - spin_lock(&wdt->io_lock); - /* disable */ - out_be32(&wdt->regs->mode, 0); - spin_unlock(&wdt->io_lock); - return 0; -} - - /* file operations */ static ssize_t mpc5200_wdt_write(struct file *file, const char __user *data, - size_t len, loff_t *ppos) + size_t len, loff_t *ppos) { struct mpc5200_wdt *wdt = file->private_data; - mpc5200_wdt_ping(wdt); + mpc52xx_gpt_wdt_ping(wdt->timer); return 0; } + static struct watchdog_info mpc5200_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, - .identity = "mpc5200 watchdog on GPT0", + .identity = WDT_IDENTITY, }; + static long mpc5200_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) + unsigned long arg) { struct mpc5200_wdt *wdt = file->private_data; int __user *data = (int __user *)arg; int timeout; + u64 real_timeout; int ret = 0; switch (cmd) { case WDIOC_GETSUPPORT: ret = copy_to_user(data, &mpc5200_wdt_info, - sizeof(mpc5200_wdt_info)); + sizeof(mpc5200_wdt_info)); if (ret) ret = -EFAULT; break; @@ -116,19 +60,23 @@ static long mpc5200_wdt_ioctl(struct file *file, unsigned int cmd, break; case WDIOC_KEEPALIVE: - mpc5200_wdt_ping(wdt); + mpc52xx_gpt_wdt_ping(wdt->timer); break; case WDIOC_SETTIMEOUT: ret = get_user(timeout, data); if (ret) break; - mpc5200_wdt_set_timeout(wdt, timeout); - mpc5200_wdt_start(wdt); + ret = mpc52xx_gpt_wdt_start(wdt->timer, timeout); + if (ret) + break; + wdt->timeout = timeout; /* fall through and return the timeout */ case WDIOC_GETTIMEOUT: - timeout = mpc5200_wdt_get_timeout(wdt); + real_timeout = mpc52xx_gpt_timer_period(wdt->timer); + do_div(real_timeout, 1000000000); + timeout = (int) real_timeout; ret = put_user(timeout, data); break; @@ -140,154 +88,90 @@ static long mpc5200_wdt_ioctl(struct file *file, unsigned int cmd, static int mpc5200_wdt_open(struct inode *inode, struct file *file) { + int ret; + /* /dev/watchdog can only be opened once */ if (test_and_set_bit(0, &is_active)) return -EBUSY; /* Set and activate the watchdog */ - mpc5200_wdt_set_timeout(wdt_global, 30); - mpc5200_wdt_start(wdt_global); + ret = mpc52xx_gpt_wdt_start(wdt_global->timer, 30); + if (ret) { + clear_bit(0, &is_active); + return ret; + } + wdt_global->timeout = 30; + file->private_data = wdt_global; return nonseekable_open(inode, file); } + static int mpc5200_wdt_release(struct inode *inode, struct file *file) { -#if WATCHDOG_NOWAYOUT == 0 +#if !defined(CONFIG_WATCHDOG_NOWAYOUT) struct mpc5200_wdt *wdt = file->private_data; - mpc5200_wdt_stop(wdt); - wdt->count = 0; /* == disabled */ + mpc52xx_gpt_wdt_stop(wdt->timer); + wdt->timeout = 0; /* == disabled */ #endif clear_bit(0, &is_active); return 0; } static const struct file_operations mpc5200_wdt_fops = { - .owner = THIS_MODULE, - .write = mpc5200_wdt_write, + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = mpc5200_wdt_write, .unlocked_ioctl = mpc5200_wdt_ioctl, - .open = mpc5200_wdt_open, - .release = mpc5200_wdt_release, + .open = mpc5200_wdt_open, + .release = mpc5200_wdt_release, +}; + +static struct miscdevice mpc5200_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &mpc5200_wdt_fops, }; /* module operations */ -static int mpc5200_wdt_probe(struct of_device *op, - const struct of_device_id *match) +static int __init mpc5200_wdt_init(void) { - struct mpc5200_wdt *wdt; int err; - const void *has_wdt; - int size; + struct mpc52xx_gpt_priv *timer; - has_wdt = of_get_property(op->node, "has-wdt", NULL); - if (!has_wdt) - has_wdt = of_get_property(op->node, "fsl,has-wdt", NULL); - if (!has_wdt) + /* grab the watchdog-capable gpt */ + timer = mpc52xx_gpt_wdt_probe(); + if (!timer) { + pr_err(WDT_IDENTITY ": probing failed\n"); return -ENODEV; + } - wdt = kzalloc(sizeof(*wdt), GFP_KERNEL); - if (!wdt) + wdt_global = kzalloc(sizeof(struct mpc5200_wdt), GFP_KERNEL); + if (!wdt_global) { + mpc52xx_gpt_wdt_release(timer); return -ENOMEM; - - wdt->ipb_freq = mpc5xxx_get_bus_frequency(op->node); - - err = of_address_to_resource(op->node, 0, &wdt->mem); - if (err) - goto out_free; - size = wdt->mem.end - wdt->mem.start + 1; - if (!request_mem_region(wdt->mem.start, size, "mpc5200_wdt")) { - err = -ENODEV; - goto out_free; - } - wdt->regs = ioremap(wdt->mem.start, size); - if (!wdt->regs) { - err = -ENODEV; - goto out_release; } - - dev_set_drvdata(&op->dev, wdt); - spin_lock_init(&wdt->io_lock); - - wdt->miscdev = (struct miscdevice) { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &mpc5200_wdt_fops, - .parent = &op->dev, - }; - wdt_global = wdt; - err = misc_register(&wdt->miscdev); + wdt_global->timer = timer; + err = misc_register(&mpc5200_wdt_miscdev); if (!err) - return 0; - - iounmap(wdt->regs); -out_release: - release_mem_region(wdt->mem.start, size); -out_free: - kfree(wdt); + pr_info(WDT_IDENTITY ": registered\n"); + else { + mpc52xx_gpt_wdt_release(timer); + kfree(wdt_global); + } return err; } -static int mpc5200_wdt_remove(struct of_device *op) -{ - struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev); - - mpc5200_wdt_stop(wdt); - misc_deregister(&wdt->miscdev); - iounmap(wdt->regs); - release_mem_region(wdt->mem.start, wdt->mem.end - wdt->mem.start + 1); - kfree(wdt); - - return 0; -} -static int mpc5200_wdt_suspend(struct of_device *op, pm_message_t state) -{ - struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev); - mpc5200_wdt_stop(wdt); - return 0; -} -static int mpc5200_wdt_resume(struct of_device *op) -{ - struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev); - if (wdt->count) - mpc5200_wdt_start(wdt); - return 0; -} -static int mpc5200_wdt_shutdown(struct of_device *op) -{ - struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev); - mpc5200_wdt_stop(wdt); - return 0; -} - -static struct of_device_id mpc5200_wdt_match[] = { - { .compatible = "mpc5200-gpt", }, - { .compatible = "fsl,mpc5200-gpt", }, - {}, -}; -static struct of_platform_driver mpc5200_wdt_driver = { - .owner = THIS_MODULE, - .name = "mpc5200-gpt-wdt", - .match_table = mpc5200_wdt_match, - .probe = mpc5200_wdt_probe, - .remove = mpc5200_wdt_remove, - .suspend = mpc5200_wdt_suspend, - .resume = mpc5200_wdt_resume, - .shutdown = mpc5200_wdt_shutdown, -}; - - -static int __init mpc5200_wdt_init(void) -{ - return of_register_platform_driver(&mpc5200_wdt_driver); -} - static void __exit mpc5200_wdt_exit(void) { - of_unregister_platform_driver(&mpc5200_wdt_driver); + mpc52xx_gpt_wdt_release(wdt_global->timer); + misc_deregister(&mpc5200_wdt_miscdev); + kfree(wdt_global); } module_init(mpc5200_wdt_init); module_exit(mpc5200_wdt_exit); -MODULE_AUTHOR("Domen Puncer "); +MODULE_AUTHOR("Domen Puncer , " + "Albrecht Dreß "); MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);