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-rw-r--r--drivers/amba/bus.c88
-rw-r--r--include/linux/amba/bus.h11
2 files changed, 80 insertions, 19 deletions
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index f60b2b6a0931..d31590e7011b 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -122,6 +122,31 @@ static int __init amba_init(void)
postcore_initcall(amba_init);
+static int amba_get_enable_pclk(struct amba_device *pcdev)
+{
+ struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
+ int ret;
+
+ pcdev->pclk = pclk;
+
+ if (IS_ERR(pclk))
+ return PTR_ERR(pclk);
+
+ ret = clk_enable(pclk);
+ if (ret)
+ clk_put(pclk);
+
+ return ret;
+}
+
+static void amba_put_disable_pclk(struct amba_device *pcdev)
+{
+ struct clk *pclk = pcdev->pclk;
+
+ clk_disable(pclk);
+ clk_put(pclk);
+}
+
/*
* These are the device model conversion veneers; they convert the
* device model structures to our more specific structures.
@@ -130,17 +155,33 @@ static int amba_probe(struct device *dev)
{
struct amba_device *pcdev = to_amba_device(dev);
struct amba_driver *pcdrv = to_amba_driver(dev->driver);
- struct amba_id *id;
+ struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
+ int ret;
- id = amba_lookup(pcdrv->id_table, pcdev);
+ do {
+ ret = amba_get_enable_pclk(pcdev);
+ if (ret)
+ break;
+
+ ret = pcdrv->probe(pcdev, id);
+ if (ret == 0)
+ break;
- return pcdrv->probe(pcdev, id);
+ amba_put_disable_pclk(pcdev);
+ } while (0);
+
+ return ret;
}
static int amba_remove(struct device *dev)
{
+ struct amba_device *pcdev = to_amba_device(dev);
struct amba_driver *drv = to_amba_driver(dev->driver);
- return drv->remove(to_amba_device(dev));
+ int ret = drv->remove(pcdev);
+
+ amba_put_disable_pclk(pcdev);
+
+ return ret;
}
static void amba_shutdown(struct device *dev)
@@ -203,7 +244,6 @@ static void amba_device_release(struct device *dev)
*/
int amba_device_register(struct amba_device *dev, struct resource *parent)
{
- u32 pid, cid;
u32 size;
void __iomem *tmp;
int i, ret;
@@ -241,25 +281,35 @@ int amba_device_register(struct amba_device *dev, struct resource *parent)
goto err_release;
}
- /*
- * Read pid and cid based on size of resource
- * they are located at end of region
- */
- for (pid = 0, i = 0; i < 4; i++)
- pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * 8);
- for (cid = 0, i = 0; i < 4; i++)
- cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8);
+ ret = amba_get_enable_pclk(dev);
+ if (ret == 0) {
+ u32 pid, cid;
- iounmap(tmp);
+ /*
+ * Read pid and cid based on size of resource
+ * they are located at end of region
+ */
+ for (pid = 0, i = 0; i < 4; i++)
+ pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
+ (i * 8);
+ for (cid = 0, i = 0; i < 4; i++)
+ cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
+ (i * 8);
- if (cid == 0xb105f00d)
- dev->periphid = pid;
+ amba_put_disable_pclk(dev);
- if (!dev->periphid) {
- ret = -ENODEV;
- goto err_release;
+ if (cid == 0xb105f00d)
+ dev->periphid = pid;
+
+ if (!dev->periphid)
+ ret = -ENODEV;
}
+ iounmap(tmp);
+
+ if (ret)
+ goto err_release;
+
ret = device_add(&dev->dev);
if (ret)
goto err_release;
diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index 8b1038607831..b0c174012436 100644
--- a/include/linux/amba/bus.h
+++ b/include/linux/amba/bus.h
@@ -14,14 +14,19 @@
#ifndef ASMARM_AMBA_H
#define ASMARM_AMBA_H
+#include <linux/clk.h>
#include <linux/device.h>
+#include <linux/err.h>
#include <linux/resource.h>
#define AMBA_NR_IRQS 2
+struct clk;
+
struct amba_device {
struct device dev;
struct resource res;
+ struct clk *pclk;
u64 dma_mask;
unsigned int periphid;
unsigned int irq[AMBA_NR_IRQS];
@@ -59,6 +64,12 @@ struct amba_device *amba_find_device(const char *, struct device *, unsigned int
int amba_request_regions(struct amba_device *, const char *);
void amba_release_regions(struct amba_device *);
+#define amba_pclk_enable(d) \
+ (IS_ERR((d)->pclk) ? 0 : clk_enable((d)->pclk))
+
+#define amba_pclk_disable(d) \
+ do { if (!IS_ERR((d)->pclk)) clk_disable((d)->pclk); } while (0)
+
#define amba_config(d) (((d)->periphid >> 24) & 0xff)
#define amba_rev(d) (((d)->periphid >> 20) & 0x0f)
#define amba_manf(d) (((d)->periphid >> 12) & 0xff)