| /* |
| * 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 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"); |