Move set of TRNG_HALFR in atmel_trng_init() as this function is also called on resume path. In case of SAMA7G5 where backup and self-refresh PM mode is available most of the SoC parts are powered of (including TRNG) when entering suspend. In that case on resuming path TRNG_HALFR should also be re-configured. Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx> --- drivers/char/hw_random/atmel-rng.c | 49 +++++++++++++++--------------- 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/drivers/char/hw_random/atmel-rng.c b/drivers/char/hw_random/atmel-rng.c index 17f02049c112..ef49dbe681cf 100644 --- a/drivers/char/hw_random/atmel-rng.c +++ b/drivers/char/hw_random/atmel-rng.c @@ -36,6 +36,7 @@ struct atmel_trng { struct clk *clk; void __iomem *base; struct hwrng rng; + bool has_half_rate; }; static bool atmel_trng_wait_ready(struct atmel_trng *trng, bool wait) @@ -74,14 +75,32 @@ static int atmel_trng_read(struct hwrng *rng, void *buf, size_t max, return ret; } -static void atmel_trng_init(struct atmel_trng *trng) +static int atmel_trng_init(struct atmel_trng *trng) { + unsigned long rate; + int ret; + + ret = clk_prepare_enable(trng->clk); + if (ret) + return ret; + + if (trng->has_half_rate) { + rate = clk_get_rate(trng->clk); + + /* if peripheral clk is above 100MHz, set HALFR */ + if (rate > 100000000) + writel(TRNG_HALFR, trng->base + TRNG_MR); + } + writel(TRNG_KEY | 1, trng->base + TRNG_CR); + + return 0; } static void atmel_trng_cleanup(struct atmel_trng *trng) { writel(TRNG_KEY, trng->base + TRNG_CR); + clk_disable_unprepare(trng->clk); } static int atmel_trng_probe(struct platform_device *pdev) @@ -105,22 +124,14 @@ static int atmel_trng_probe(struct platform_device *pdev) if (!data) return -ENODEV; - if (data->has_half_rate) { - unsigned long rate = clk_get_rate(trng->clk); - - /* if peripheral clk is above 100MHz, set HALFR */ - if (rate > 100000000) - writel(TRNG_HALFR, trng->base + TRNG_MR); - } + trng->has_half_rate = data->has_half_rate; + trng->rng.name = pdev->name; + trng->rng.read = atmel_trng_read; - ret = clk_prepare_enable(trng->clk); + ret = atmel_trng_init(trng); if (ret) return ret; - atmel_trng_init(trng); - trng->rng.name = pdev->name; - trng->rng.read = atmel_trng_read; - ret = devm_hwrng_register(&pdev->dev, &trng->rng); if (ret) goto err_register; @@ -130,7 +141,6 @@ static int atmel_trng_probe(struct platform_device *pdev) return 0; err_register: - clk_disable_unprepare(trng->clk); atmel_trng_cleanup(trng); return ret; } @@ -141,7 +151,6 @@ static int atmel_trng_remove(struct platform_device *pdev) atmel_trng_cleanup(trng); - clk_disable_unprepare(trng->clk); return 0; } @@ -152,7 +161,6 @@ static int atmel_trng_suspend(struct device *dev) struct atmel_trng *trng = dev_get_drvdata(dev); atmel_trng_cleanup(trng); - clk_disable_unprepare(trng->clk); return 0; } @@ -160,15 +168,8 @@ static int atmel_trng_suspend(struct device *dev) static int atmel_trng_resume(struct device *dev) { struct atmel_trng *trng = dev_get_drvdata(dev); - int ret; - ret = clk_prepare_enable(trng->clk); - if (ret) - return ret; - - atmel_trng_init(trng); - - return 0; + return atmel_trng_init(trng); } static const struct dev_pm_ops atmel_trng_pm_ops = { -- 2.32.0