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path: root/drivers/char/hw_random/omap-rng.c
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Diffstat (limited to 'drivers/char/hw_random/omap-rng.c')
-rw-r--r--drivers/char/hw_random/omap-rng.c121
1 files changed, 70 insertions, 51 deletions
diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index 4fbdceb6f773..a5effd813abd 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -18,11 +18,12 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/random.h>
-#include <linux/clk.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/hw_random.h>
#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
#include <asm/io.h>
@@ -46,26 +47,36 @@
#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
+ * @mem_res: struct resource * for the IP block registers physical memory
+ */
+struct omap_rng_private_data {
+ void __iomem *base;
+ 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 +91,13 @@ 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 +108,68 @@ 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;
-
- if (cpu_is_omap24xx()) {
- rng_ick = clk_get(&pdev->dev, "ick");
- if (IS_ERR(rng_ick)) {
- dev_err(&pdev->dev, "Could not get rng_ick\n");
- ret = PTR_ERR(rng_ick);
- return ret;
- } else
- clk_enable(rng_ick);
- }
+ priv = kzalloc(sizeof(struct omap_rng_private_data), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "could not allocate memory\n");
+ return -ENOMEM;
+ };
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ omap_rng_ops.priv = (unsigned long)priv;
+ dev_set_drvdata(&pdev->dev, priv);
- rng_base = devm_request_and_ioremap(&pdev->dev, res);
- if (!rng_base) {
+ priv->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!priv->mem_res) {
+ ret = -ENOENT;
+ goto err_ioremap;
+ }
+
+ 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);
+
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
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;
+ pm_runtime_disable(&pdev->dev);
err_ioremap:
- if (cpu_is_omap24xx()) {
- clk_disable(rng_ick);
- clk_put(rng_ick);
- }
+ 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);
- if (cpu_is_omap24xx()) {
- clk_disable(rng_ick);
- clk_put(rng_ick);
- }
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ release_mem_region(priv->mem_res->start, resource_size(priv->mem_res));
- rng_base = NULL;
+ kfree(priv);
return 0;
}
@@ -164,13 +178,21 @@ 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);
+ pm_runtime_put_sync(dev);
+
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);
+
+ pm_runtime_get_sync(dev);
+ omap_rng_write_reg(priv, RNG_MASK_REG, 0x1);
+
return 0;
}
@@ -198,9 +220,6 @@ static struct platform_driver omap_rng_driver = {
static int __init omap_rng_init(void)
{
- if (!cpu_is_omap16xx() && !cpu_is_omap24xx())
- return -ENODEV;
-
return platform_driver_register(&omap_rng_driver);
}