On 11/06/2015 12:15 AM, Aaro Koskinen wrote:
We cannot put the HW RNG to idle using a timer because we cannot disable clocks from atomic context. Use a delayed work instead.Fixes a warning with CONFIG_DEBUG_MUTEXES on Nokia N900 during boot. Reported-by: Sebastian Reichel <s...@kernel.org> Signed-off-by: Aaro Koskinen <aaro.koski...@iki.fi> --- drivers/char/hw_random/omap3-rom-rng.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/char/hw_random/omap3-rom-rng.c b/drivers/char/hw_random/omap3-rom-rng.c index a405cdc..58191c6 100644 --- a/drivers/char/hw_random/omap3-rom-rng.c +++ b/drivers/char/hw_random/omap3-rom-rng.c @@ -29,11 +29,11 @@ /* param1: ptr, param2: count, param3: flag */ static u32 (*omap3_rom_rng_call)(u32, u32, u32); -static struct timer_list idle_timer; +static struct delayed_work idle_work; static int rng_idle; static struct clk *rng_clk; -static void omap3_rom_rng_idle(unsigned long data) +static void omap3_rom_rng_idle(struct work_struct *work) { int r; @@ -51,7 +51,7 @@ static int omap3_rom_rng_get_random(void *buf, unsigned int count) u32 r; u32 ptr; - del_timer_sync(&idle_timer); + cancel_delayed_work_sync(&idle_work); if (rng_idle) { clk_prepare_enable(rng_clk); r = omap3_rom_rng_call(0, 0, RNG_GEN_PRNG_HW_INIT); @@ -65,7 +65,7 @@ static int omap3_rom_rng_get_random(void *buf, unsigned int count) ptr = virt_to_phys(buf); r = omap3_rom_rng_call(ptr, count, RNG_GEN_HW); - mod_timer(&idle_timer, jiffies + msecs_to_jiffies(500)); + schedule_delayed_work(&idle_work, msecs_to_jiffies(500)); if (r != 0) return -EINVAL; return 0; @@ -102,7 +102,7 @@ static int omap3_rom_rng_probe(struct platform_device *pdev) return -EINVAL; } - setup_timer(&idle_timer, omap3_rom_rng_idle, 0); + INIT_DELAYED_WORK(&idle_work, omap3_rom_rng_idle); rng_clk = devm_clk_get(&pdev->dev, "ick"); if (IS_ERR(rng_clk)) { pr_err("unable to get RNG clock\n"); @@ -118,6 +118,7 @@ static int omap3_rom_rng_probe(struct platform_device *pdev) static int omap3_rom_rng_remove(struct platform_device *pdev) { + cancel_delayed_work_sync(&idle_work); hwrng_unregister(&omap3_rom_rng_ops); clk_disable_unprepare(rng_clk); return 0;
Sry, It looks like PM runtime autosuspend might work well here. What do you think? -- regards, -grygorii -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
