[PATCH 14/15] watchdog/mpcore_wdt: Add clock framework support
From: Viresh Kumar <hidden>
Date: 2012-03-07 10:27:55
Also in:
linux-watchdog
Subsystem:
the rest, watchdog device drivers · Maintainers:
Linus Torvalds, Wim Van Sebroeck, Guenter Roeck
This patch adds in clk framework support for wdt driver. If clk_get fails for some platform, then we continue without clk_* API's. Signed-off-by: Viresh Kumar <redacted> --- drivers/watchdog/mpcore_wdt.c | 71 ++++++++++++++++++++++++++++++++++++----- 1 files changed, 63 insertions(+), 8 deletions(-)
diff --git a/drivers/watchdog/mpcore_wdt.c b/drivers/watchdog/mpcore_wdt.c
index ebd964a..9747193 100644
--- a/drivers/watchdog/mpcore_wdt.c
+++ b/drivers/watchdog/mpcore_wdt.c@@ -17,6 +17,7 @@ * * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> */ +#include <linux/clk.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/interrupt.h>
@@ -39,6 +40,7 @@ struct mpcore_wdt { unsigned long boot_status; struct device *dev; void __iomem *base; + struct clk *clk; int irq; unsigned int perturb; char expect_close;
@@ -147,6 +149,7 @@ static int mpcore_wdt_set_heartbeat(int t) static int mpcore_wdt_open(struct inode *inode, struct file *file) { struct mpcore_wdt *wdt = platform_get_drvdata(mpcore_wdt_pdev); + int ret; if (test_and_set_bit(0, &wdt->timer_alive)) return -EBUSY;
@@ -156,10 +159,22 @@ static int mpcore_wdt_open(struct inode *inode, struct file *file) file->private_data = wdt; + if (wdt->clk) { + ret = clk_enable(wdt->clk); + if (ret) { + dev_err(wdt->dev, "clock enable fail"); + goto err; + } + } + /* Activate timer */ mpcore_wdt_start(wdt); return nonseekable_open(inode, file); + +err: + clear_bit(0, &wdt->timer_alive); + return ret; } static int mpcore_wdt_release(struct inode *inode, struct file *file)
@@ -169,9 +184,12 @@ static int mpcore_wdt_release(struct inode *inode, struct file *file) /* * Shut off the timer. Lock it in if it's a module and we set nowayout */ - if (wdt->expect_close == 42) + if (wdt->expect_close == 42) { mpcore_wdt_stop(wdt); - else { + + if (wdt->clk) + clk_disable(wdt->clk); + } else { dev_printk(KERN_CRIT, wdt->dev, "unexpected close, not stopping watchdog!\n"); mpcore_wdt_keepalive(wdt);
@@ -350,6 +368,28 @@ static int __devinit mpcore_wdt_probe(struct platform_device *pdev) } } + wdt->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(wdt->clk)) { + dev_warn(&pdev->dev, "Clock not found\n"); + wdt->clk = NULL; + } + + if (wdt->clk) { + ret = clk_enable(wdt->clk); + if (ret) { + dev_err(&pdev->dev, "Clock enable failed\n"); + goto err_put_clk; + } + } + + wdt->boot_status = (readl(wdt->base + TWD_WDOG_RESETSTAT) & + TWD_WDOG_RESETSTAT_MASK) ? WDIOF_CARDRESET : 0; + + mpcore_wdt_stop(wdt); + + if (wdt->clk) + clk_disable(wdt->clk); + /* * Check that the margin value is within it's range; * if not reset to the default
@@ -368,25 +408,32 @@ static int __devinit mpcore_wdt_probe(struct platform_device *pdev) dev_printk(KERN_ERR, wdt->dev, "cannot register miscdev on minor=%d (err=%d)\n", WATCHDOG_MINOR, ret); - return ret; + goto err_put_clk; } - wdt->boot_status = (readl(wdt->base + TWD_WDOG_RESETSTAT) & - TWD_WDOG_RESETSTAT_MASK) ? WDIOF_CARDRESET : 0; - - mpcore_wdt_stop(wdt); platform_set_drvdata(pdev, wdt); mpcore_wdt_pdev = pdev; return 0; + +err_put_clk: + if (wdt->clk) + clk_put(wdt->clk); + + return ret; } static int __devexit mpcore_wdt_remove(struct platform_device *pdev) { + struct mpcore_wdt *wdt = platform_get_drvdata(pdev); + platform_set_drvdata(pdev, NULL); misc_deregister(&mpcore_wdt_miscdev); + if (wdt->clk) + clk_put(wdt->clk); + mpcore_wdt_pdev = NULL; return 0;
@@ -399,6 +446,9 @@ static int mpcore_wdt_suspend(struct device *dev) if (test_bit(0, &wdt->timer_alive)) mpcore_wdt_stop(wdt); /* Turn the WDT off */ + + if (wdt->clk) + clk_disable(wdt->clk); return 0; }
@@ -407,8 +457,13 @@ static int mpcore_wdt_resume(struct device *dev) struct mpcore_wdt *wdt = dev_get_drvdata(dev); /* re-activate timer */ - if (test_bit(0, &wdt->timer_alive)) + if (test_bit(0, &wdt->timer_alive)) { + if (wdt->clk) + clk_enable(wdt->clk); + mpcore_wdt_start(wdt); + } + return 0; } #endif
--
1.7.8.110.g4cb5d