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path: root/drivers/char/hw_random/bcm63xx-rng.c
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Diffstat (limited to 'drivers/char/hw_random/bcm63xx-rng.c')
-rw-r--r--drivers/char/hw_random/bcm63xx-rng.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/char/hw_random/bcm63xx-rng.c b/drivers/char/hw_random/bcm63xx-rng.c
new file mode 100644
index 000000000000..aec6a4277caa
--- /dev/null
+++ b/drivers/char/hw_random/bcm63xx-rng.c
@@ -0,0 +1,175 @@
+/*
+ * Broadcom BCM63xx Random Number Generator support
+ *
+ * Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
+ * Copyright (C) 2009, Broadcom Corporation
+ *
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+
+#include <bcm63xx_io.h>
+#include <bcm63xx_regs.h>
+
+struct bcm63xx_rng_priv {
+ struct clk *clk;
+ void __iomem *regs;
+};
+
+#define to_rng_priv(rng) ((struct bcm63xx_rng_priv *)rng->priv)
+
+static int bcm63xx_rng_init(struct hwrng *rng)
+{
+ struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+ u32 val;
+
+ val = bcm_readl(priv->regs + RNG_CTRL);
+ val |= RNG_EN;
+ bcm_writel(val, priv->regs + RNG_CTRL);
+
+ return 0;
+}
+
+static void bcm63xx_rng_cleanup(struct hwrng *rng)
+{
+ struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+ u32 val;
+
+ val = bcm_readl(priv->regs + RNG_CTRL);
+ val &= ~RNG_EN;
+ bcm_writel(val, priv->regs + RNG_CTRL);
+}
+
+static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
+{
+ struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+ return bcm_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
+}
+
+static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+ *data = bcm_readl(priv->regs + RNG_DATA);
+
+ return 4;
+}
+
+static int __devinit bcm63xx_rng_probe(struct platform_device *pdev)
+{
+ struct resource *r;
+ struct clk *clk;
+ int ret;
+ struct bcm63xx_rng_priv *priv;
+ struct hwrng *rng;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ dev_err(&pdev->dev, "no iomem resource\n");
+ ret = -ENXIO;
+ goto out;
+ }
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "no memory for private structure\n");
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ rng = kzalloc(sizeof(*rng), GFP_KERNEL);
+ if (!rng) {
+ dev_err(&pdev->dev, "no memory for rng structure\n");
+ ret = -ENOMEM;
+ goto out_free_priv;
+ }
+
+ platform_set_drvdata(pdev, rng);
+ rng->priv = (unsigned long)priv;
+ rng->name = pdev->name;
+ rng->init = bcm63xx_rng_init;
+ rng->cleanup = bcm63xx_rng_cleanup;
+ rng->data_present = bcm63xx_rng_data_present;
+ rng->data_read = bcm63xx_rng_data_read;
+
+ clk = clk_get(&pdev->dev, "ipsec");
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "no clock for device\n");
+ ret = PTR_ERR(clk);
+ goto out_free_rng;
+ }
+
+ priv->clk = clk;
+
+ if (!devm_request_mem_region(&pdev->dev, r->start,
+ resource_size(r), pdev->name)) {
+ dev_err(&pdev->dev, "request mem failed");
+ ret = -ENOMEM;
+ goto out_free_rng;
+ }
+
+ priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
+ resource_size(r));
+ if (!priv->regs) {
+ dev_err(&pdev->dev, "ioremap failed");
+ ret = -ENOMEM;
+ goto out_free_rng;
+ }
+
+ clk_enable(clk);
+
+ ret = hwrng_register(rng);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register rng device\n");
+ goto out_clk_disable;
+ }
+
+ dev_info(&pdev->dev, "registered RNG driver\n");
+
+ return 0;
+
+out_clk_disable:
+ clk_disable(clk);
+out_free_rng:
+ platform_set_drvdata(pdev, NULL);
+ kfree(rng);
+out_free_priv:
+ kfree(priv);
+out:
+ return ret;
+}
+
+static int __devexit bcm63xx_rng_remove(struct platform_device *pdev)
+{
+ struct hwrng *rng = platform_get_drvdata(pdev);
+ struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+ hwrng_unregister(rng);
+ clk_disable(priv->clk);
+ kfree(priv);
+ kfree(rng);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver bcm63xx_rng_driver = {
+ .probe = bcm63xx_rng_probe,
+ .remove = __devexit_p(bcm63xx_rng_remove),
+ .driver = {
+ .name = "bcm63xx-rng",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(bcm63xx_rng_driver);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
+MODULE_LICENSE("GPL");