Revert "clocksource: sh_tmu: Runtime PM support" (d4905ce3) · Commits · 戴 / test

This reverts commit . There is a fundamental ordering race between the early and late probe paths and the runtime PM tie-in that results in __pm_runtime_resume() attempting to take a lock that hasn't been initialized yet (which by proxy also suggests that pm_runtime_init() hasn't yet been run on the device either, making the entire thing unsafe) -- resulting in instant death on SMP or on UP with spinlock debugging enabled: sh_tmu.0: used for clock events sh_tmu.0: used for periodic clock events BUG: spinlock trylock failure on UP on CPU#0, swapper/0 lock: 804db198, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 ... Revert it for now until the ordering issues can be resolved, or we can get some more help from the runtime PM framework to make this possible. Signed-off-by:

Paul Mundt <lethal@linux-sh.org>

drivers/clocksource/sh_tmu.c

+2 −10

Original line number	Diff line number	Diff line
		@@ -25,7 +25,6 @@
		#include <linux/delay.h>
		#include <linux/io.h>
		#include <linux/clk.h>
		#include <linux/pm_runtime.h>
		#include <linux/irq.h>
		#include <linux/err.h>
		#include <linux/clocksource.h>
		@@ -110,12 +109,10 @@ static int sh_tmu_enable(struct sh_tmu_priv *p)
		{
		int ret;

		/* wake up device and enable clock */
		pm_runtime_get_sync(&p->pdev->dev);
		/* enable clock */
		ret = clk_enable(p->clk);
		if (ret) {
		dev_err(&p->pdev->dev, "cannot enable clock\n");
		pm_runtime_put_sync(&p->pdev->dev);
		return ret;
		}

		@@ -144,9 +141,8 @@ static void sh_tmu_disable(struct sh_tmu_priv *p)
		/* disable interrupts in TMU block */
		sh_tmu_write(p, TCR, 0x0000);

		/* stop clock and mark device as idle */
		/* stop clock */
		clk_disable(p->clk);
		pm_runtime_put_sync(&p->pdev->dev);
		}

		static void sh_tmu_set_next(struct sh_tmu_priv *p, unsigned long delta,
		@@ -415,7 +411,6 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev)

		if (p) {
		dev_info(&pdev->dev, "kept as earlytimer\n");
		pm_runtime_enable(&pdev->dev);
		return 0;
		}

		@@ -430,9 +425,6 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev)
		kfree(p);
		platform_set_drvdata(pdev, NULL);
		}

		if (!is_early_platform_device(pdev))
		pm_runtime_enable(&pdev->dev);
		return ret;
		}

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