hwrng: OMAP: store per-device data in per-device variables, not file statics
authorPaul Walmsley <paul@pwsan.com>
Sun, 23 Sep 2012 23:28:26 +0000 (17:28 -0600)
committerPaul Walmsley <paul@pwsan.com>
Sun, 23 Sep 2012 23:28:26 +0000 (17:28 -0600)
Encapsulate all of the RNG per-device state into a single per-device
structure record, as opposed to a set of per-driver file variables.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
drivers/char/hw_random/omap-rng.c

index 4fbdceb6f773d7e45189a22347668c34a0b52c63..e0f0b9839862c08488c4237cf641d386f0256259 100644 (file)
@@ -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>
 
 #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;
 }