diff options
Diffstat (limited to 'drivers/char/hw_random/omap-rng.c')
| -rw-r--r-- | drivers/char/hw_random/omap-rng.c | 84 |
1 files changed, 42 insertions, 42 deletions
diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c index 74d11ae6abe9..5e8b50f15db7 100644 --- a/drivers/char/hw_random/omap-rng.c +++ b/drivers/char/hw_random/omap-rng.c @@ -22,15 +22,13 @@ #include <linux/platform_device.h> #include <linux/hw_random.h> #include <linux/delay.h> +#include <linux/kernel.h> #include <linux/slab.h> #include <linux/pm_runtime.h> #include <linux/of.h> -#include <linux/of_device.h> -#include <linux/of_address.h> #include <linux/interrupt.h> #include <linux/clk.h> - -#include <asm/io.h> +#include <linux/io.h> #define RNG_REG_STATUS_RDY (1 << 0) @@ -66,6 +64,13 @@ #define OMAP4_RNG_OUTPUT_SIZE 0x8 #define EIP76_RNG_OUTPUT_SIZE 0x10 +/* + * EIP76 RNG takes approx. 700us to produce 16 bytes of output data + * as per testing results. And to account for the lack of udelay()'s + * reliability, we keep the timeout as 1000us. + */ +#define RNG_DATA_FILL_TIMEOUT 100 + enum { RNG_OUTPUT_0_REG = 0, RNG_OUTPUT_1_REG, @@ -150,6 +155,7 @@ struct omap_rng_dev { const struct omap_rng_pdata *pdata; struct hwrng rng; struct clk *clk; + struct clk *clk_reg; }; static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg) @@ -175,7 +181,7 @@ static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max, if (max < priv->pdata->data_size) return 0; - for (i = 0; i < 20; i++) { + for (i = 0; i < RNG_DATA_FILL_TIMEOUT; i++) { present = priv->pdata->data_present(priv); if (present || !wait) break; @@ -235,7 +241,6 @@ static struct omap_rng_pdata omap2_rng_pdata = { .cleanup = omap2_rng_cleanup, }; -#if defined(CONFIG_OF) static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv) { return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY; @@ -350,7 +355,7 @@ static struct omap_rng_pdata eip76_rng_pdata = { .cleanup = omap4_rng_cleanup, }; -static const struct of_device_id omap_rng_of_match[] = { +static const struct of_device_id omap_rng_of_match[] __maybe_unused = { { .compatible = "ti,omap2-rng", .data = &omap2_rng_pdata, @@ -370,25 +375,19 @@ MODULE_DEVICE_TABLE(of, omap_rng_of_match); static int of_get_omap_rng_device_details(struct omap_rng_dev *priv, struct platform_device *pdev) { - const struct of_device_id *match; struct device *dev = &pdev->dev; int irq, err; - match = of_match_device(of_match_ptr(omap_rng_of_match), dev); - if (!match) { - dev_err(dev, "no compatible OF match\n"); - return -EINVAL; - } - priv->pdata = match->data; + priv->pdata = of_device_get_match_data(dev); + if (!priv->pdata) + return -ENODEV; + if (of_device_is_compatible(dev->of_node, "ti,omap4-rng") || of_device_is_compatible(dev->of_node, "inside-secure,safexcel-eip76")) { irq = platform_get_irq(pdev, 0); - if (irq < 0) { - dev_err(dev, "%s: error getting IRQ resource - %d\n", - __func__, irq); + if (irq < 0) return irq; - } err = devm_request_irq(dev, irq, omap4_rng_irq, IRQF_TRIGGER_NONE, dev_name(dev), priv); @@ -413,13 +412,6 @@ static int of_get_omap_rng_device_details(struct omap_rng_dev *priv, } return 0; } -#else -static int of_get_omap_rng_device_details(struct omap_rng_dev *omap_rng, - struct platform_device *pdev) -{ - return -EINVAL; -} -#endif static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng) { @@ -431,7 +423,6 @@ static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng) static int omap_rng_probe(struct platform_device *pdev) { struct omap_rng_dev *priv; - struct resource *res; struct device *dev = &pdev->dev; int ret; @@ -442,13 +433,13 @@ static int omap_rng_probe(struct platform_device *pdev) priv->rng.read = omap_rng_do_read; priv->rng.init = omap_rng_init; priv->rng.cleanup = omap_rng_cleanup; + priv->rng.quality = 900; priv->rng.priv = (unsigned long)priv; platform_set_drvdata(pdev, priv); priv->dev = dev; - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - priv->base = devm_ioremap_resource(dev, res); + priv->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(priv->base)) { ret = PTR_ERR(priv->base); goto err_ioremap; @@ -461,15 +452,14 @@ static int omap_rng_probe(struct platform_device *pdev) } pm_runtime_enable(&pdev->dev); - ret = pm_runtime_get_sync(&pdev->dev); + ret = pm_runtime_resume_and_get(&pdev->dev); if (ret < 0) { dev_err(&pdev->dev, "Failed to runtime_get device: %d\n", ret); - pm_runtime_put_noidle(&pdev->dev); goto err_ioremap; } priv->clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER) + if (PTR_ERR(priv->clk) == -EPROBE_DEFER) return -EPROBE_DEFER; if (!IS_ERR(priv->clk)) { ret = clk_prepare_enable(priv->clk); @@ -480,12 +470,25 @@ static int omap_rng_probe(struct platform_device *pdev) } } + priv->clk_reg = devm_clk_get(&pdev->dev, "reg"); + if (PTR_ERR(priv->clk_reg) == -EPROBE_DEFER) + return -EPROBE_DEFER; + if (!IS_ERR(priv->clk_reg)) { + ret = clk_prepare_enable(priv->clk_reg); + if (ret) { + dev_err(&pdev->dev, + "Unable to enable the register clk: %d\n", + ret); + goto err_register; + } + } + ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) : get_omap_rng_device_details(priv); if (ret) goto err_register; - ret = hwrng_register(&priv->rng); + ret = devm_hwrng_register(&pdev->dev, &priv->rng); if (ret) goto err_register; @@ -499,28 +502,25 @@ err_register: pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); - if (!IS_ERR(priv->clk)) - clk_disable_unprepare(priv->clk); + clk_disable_unprepare(priv->clk_reg); + clk_disable_unprepare(priv->clk); err_ioremap: dev_err(dev, "initialization failed.\n"); return ret; } -static int omap_rng_remove(struct platform_device *pdev) +static void omap_rng_remove(struct platform_device *pdev) { struct omap_rng_dev *priv = platform_get_drvdata(pdev); - hwrng_unregister(&priv->rng); priv->pdata->cleanup(priv); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); - if (!IS_ERR(priv->clk)) - clk_disable_unprepare(priv->clk); - - return 0; + clk_disable_unprepare(priv->clk); + clk_disable_unprepare(priv->clk_reg); } static int __maybe_unused omap_rng_suspend(struct device *dev) @@ -538,10 +538,9 @@ static int __maybe_unused omap_rng_resume(struct device *dev) struct omap_rng_dev *priv = dev_get_drvdata(dev); int ret; - ret = pm_runtime_get_sync(dev); + ret = pm_runtime_resume_and_get(dev); if (ret < 0) { dev_err(dev, "Failed to runtime_get device: %d\n", ret); - pm_runtime_put_noidle(dev); return ret; } @@ -565,4 +564,5 @@ static struct platform_driver omap_rng_driver = { module_platform_driver(omap_rng_driver); MODULE_ALIAS("platform:omap_rng"); MODULE_AUTHOR("Deepak Saxena (and others)"); +MODULE_DESCRIPTION("RNG driver for TI OMAP CPU family"); MODULE_LICENSE("GPL"); |
