diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/hw_random/omap-rng.c | 115 |
1 files changed, 77 insertions, 38 deletions
diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c index 4fbdceb6f773..e0f0b9839862 100644 --- a/drivers/char/hw_random/omap-rng.c +++ b/drivers/char/hw_random/omap-rng.c @@ -23,6 +23,7 @@ #include <linux/platform_device.h> #include <linux/hw_random.h> #include <linux/delay.h> +#include <linux/slab.h> #include <asm/io.h> @@ -46,26 +47,38 @@ #define RNG_SYSSTATUS 0x44 /* System status [0] = RESETDONE */ -static void __iomem *rng_base; -static struct clk *rng_ick; -static struct platform_device *rng_dev; +/** + * struct omap_rng_private_data - RNG IP block-specific data + * @base: virtual address of the beginning of the RNG IP block registers + * @clk: RNG clock + * @mem_res: struct resource * for the IP block registers physical memory + */ +struct omap_rng_private_data { + void __iomem *base; + struct clk *clk; + struct resource *mem_res; +}; -static inline u32 omap_rng_read_reg(int reg) +static inline u32 omap_rng_read_reg(struct omap_rng_private_data *priv, int reg) { - return __raw_readl(rng_base + reg); + return __raw_readl(priv->base + reg); } -static inline void omap_rng_write_reg(int reg, u32 val) +static inline void omap_rng_write_reg(struct omap_rng_private_data *priv, + int reg, u32 val) { - __raw_writel(val, rng_base + reg); + __raw_writel(val, priv->base + reg); } static int omap_rng_data_present(struct hwrng *rng, int wait) { + struct omap_rng_private_data *priv; int data, i; + priv = (struct omap_rng_private_data *)rng->priv; + for (i = 0; i < 20; i++) { - data = omap_rng_read_reg(RNG_STAT_REG) ? 0 : 1; + data = omap_rng_read_reg(priv, RNG_STAT_REG) ? 0 : 1; if (data || !wait) break; /* RNG produces data fast enough (2+ MBit/sec, even @@ -80,9 +93,13 @@ static int omap_rng_data_present(struct hwrng *rng, int wait) static int omap_rng_data_read(struct hwrng *rng, u32 *data) { - *data = omap_rng_read_reg(RNG_OUT_REG); + struct omap_rng_private_data *priv; + + priv = (struct omap_rng_private_data *)rng->priv; + + *data = omap_rng_read_reg(priv, RNG_OUT_REG); - return 4; + return sizeof(u32); } static struct hwrng omap_rng_ops = { @@ -93,69 +110,85 @@ static struct hwrng omap_rng_ops = { static int __devinit omap_rng_probe(struct platform_device *pdev) { - struct resource *res; + struct omap_rng_private_data *priv; int ret; - /* - * A bit ugly, and it will never actually happen but there can - * be only one RNG and this catches any bork - */ - if (rng_dev) - return -EBUSY; + priv = kzalloc(sizeof(struct omap_rng_private_data), GFP_KERNEL); + if (!priv) { + dev_err(&pdev->dev, "could not allocate memory\n"); + return -ENOMEM; + }; + + omap_rng_ops.priv = (unsigned long)priv; + dev_set_drvdata(&pdev->dev, priv); if (cpu_is_omap24xx()) { - rng_ick = clk_get(&pdev->dev, "ick"); - if (IS_ERR(rng_ick)) { + priv->clk = clk_get(&pdev->dev, "ick"); + if (IS_ERR(priv->clk)) { dev_err(&pdev->dev, "Could not get rng_ick\n"); - ret = PTR_ERR(rng_ick); + ret = PTR_ERR(priv->clk); return ret; - } else - clk_enable(rng_ick); + } else { + clk_enable(priv->clk); + } } - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!priv->mem_res) { + ret = -ENOENT; + goto err_ioremap; + } - rng_base = devm_request_and_ioremap(&pdev->dev, res); - if (!rng_base) { + priv->base = devm_request_and_ioremap(&pdev->dev, priv->mem_res); + if (!priv->base) { ret = -ENOMEM; goto err_ioremap; } - dev_set_drvdata(&pdev->dev, res); + dev_set_drvdata(&pdev->dev, priv); ret = hwrng_register(&omap_rng_ops); if (ret) goto err_register; dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n", - omap_rng_read_reg(RNG_REV_REG)); - omap_rng_write_reg(RNG_MASK_REG, 0x1); + omap_rng_read_reg(priv, RNG_REV_REG)); + - rng_dev = pdev; + omap_rng_write_reg(priv, RNG_MASK_REG, 0x1); return 0; err_register: - rng_base = NULL; + priv->base = NULL; err_ioremap: if (cpu_is_omap24xx()) { - clk_disable(rng_ick); - clk_put(rng_ick); + clk_disable(priv->clk); + clk_put(priv->clk); } + + kfree(priv); + return ret; } static int __exit omap_rng_remove(struct platform_device *pdev) { + struct omap_rng_private_data *priv = dev_get_drvdata(&pdev->dev); + hwrng_unregister(&omap_rng_ops); - omap_rng_write_reg(RNG_MASK_REG, 0x0); + omap_rng_write_reg(priv, RNG_MASK_REG, 0x0); + + iounmap(priv->base); if (cpu_is_omap24xx()) { - clk_disable(rng_ick); - clk_put(rng_ick); + clk_disable(priv->clk); + clk_put(priv->clk); } - rng_base = NULL; + release_mem_region(priv->mem_res->start, resource_size(priv->mem_res)); + + kfree(priv); return 0; } @@ -164,13 +197,19 @@ static int __exit omap_rng_remove(struct platform_device *pdev) static int omap_rng_suspend(struct device *dev) { - omap_rng_write_reg(RNG_MASK_REG, 0x0); + struct omap_rng_private_data *priv = dev_get_drvdata(dev); + + omap_rng_write_reg(priv, RNG_MASK_REG, 0x0); + return 0; } static int omap_rng_resume(struct device *dev) { - omap_rng_write_reg(RNG_MASK_REG, 0x1); + struct omap_rng_private_data *priv = dev_get_drvdata(dev); + + omap_rng_write_reg(priv, RNG_MASK_REG, 0x1); + return 0; } |