summaryrefslogtreecommitdiff
path: root/drivers/uio/uio_dmem_genirq.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/uio/uio_dmem_genirq.c')
-rw-r--r--drivers/uio/uio_dmem_genirq.c153
1 files changed, 63 insertions, 90 deletions
diff --git a/drivers/uio/uio_dmem_genirq.c b/drivers/uio/uio_dmem_genirq.c
index 6e27fe4fcca3..41c18ec62a45 100644
--- a/drivers/uio/uio_dmem_genirq.c
+++ b/drivers/uio/uio_dmem_genirq.c
@@ -20,6 +20,7 @@
#include <linux/pm_runtime.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
+#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_platform.h>
@@ -35,16 +36,19 @@ struct uio_dmem_genirq_platdata {
struct platform_device *pdev;
unsigned int dmem_region_start;
unsigned int num_dmem_regions;
- void *dmem_region_vaddr[MAX_UIO_MAPS];
struct mutex alloc_lock;
unsigned int refcnt;
};
+/* Bits in uio_dmem_genirq_platdata.flags */
+enum {
+ UIO_IRQ_DISABLED = 0,
+};
+
static int uio_dmem_genirq_open(struct uio_info *info, struct inode *inode)
{
struct uio_dmem_genirq_platdata *priv = info->priv;
struct uio_mem *uiomem;
- int dmem_region = priv->dmem_region_start;
uiomem = &priv->uioinfo->mem[priv->dmem_region_start];
@@ -55,11 +59,8 @@ static int uio_dmem_genirq_open(struct uio_info *info, struct inode *inode)
break;
addr = dma_alloc_coherent(&priv->pdev->dev, uiomem->size,
- (dma_addr_t *)&uiomem->addr, GFP_KERNEL);
- if (!addr) {
- uiomem->addr = DMEM_MAP_ERROR;
- }
- priv->dmem_region_vaddr[dmem_region++] = addr;
+ &uiomem->dma_addr, GFP_KERNEL);
+ uiomem->addr = addr ? (uintptr_t) addr : DMEM_MAP_ERROR;
++uiomem;
}
priv->refcnt++;
@@ -74,7 +75,6 @@ static int uio_dmem_genirq_release(struct uio_info *info, struct inode *inode)
{
struct uio_dmem_genirq_platdata *priv = info->priv;
struct uio_mem *uiomem;
- int dmem_region = priv->dmem_region_start;
/* Tell the Runtime PM code that the device has become idle */
pm_runtime_put_sync(&priv->pdev->dev);
@@ -87,13 +87,12 @@ static int uio_dmem_genirq_release(struct uio_info *info, struct inode *inode)
while (!priv->refcnt && uiomem < &priv->uioinfo->mem[MAX_UIO_MAPS]) {
if (!uiomem->size)
break;
- if (priv->dmem_region_vaddr[dmem_region]) {
- dma_free_coherent(&priv->pdev->dev, uiomem->size,
- priv->dmem_region_vaddr[dmem_region],
- uiomem->addr);
+ if (uiomem->addr) {
+ dma_free_coherent(uiomem->dma_device, uiomem->size,
+ (void *) (uintptr_t) uiomem->addr,
+ uiomem->dma_addr);
}
uiomem->addr = DMEM_MAP_ERROR;
- ++dmem_region;
++uiomem;
}
@@ -109,8 +108,10 @@ static irqreturn_t uio_dmem_genirq_handler(int irq, struct uio_info *dev_info)
* remember the state so we can allow user space to enable it later.
*/
- if (!test_and_set_bit(0, &priv->flags))
+ spin_lock(&priv->lock);
+ if (!__test_and_set_bit(UIO_IRQ_DISABLED, &priv->flags))
disable_irq_nosync(irq);
+ spin_unlock(&priv->lock);
return IRQ_HANDLED;
}
@@ -124,24 +125,30 @@ static int uio_dmem_genirq_irqcontrol(struct uio_info *dev_info, s32 irq_on)
* in the interrupt controller, but keep track of the
* state to prevent per-irq depth damage.
*
- * Serialize this operation to support multiple tasks.
+ * Serialize this operation to support multiple tasks and concurrency
+ * with irq handler on SMP systems.
*/
spin_lock_irqsave(&priv->lock, flags);
if (irq_on) {
- if (test_and_clear_bit(0, &priv->flags))
+ if (__test_and_clear_bit(UIO_IRQ_DISABLED, &priv->flags))
enable_irq(dev_info->irq);
- spin_unlock_irqrestore(&priv->lock, flags);
} else {
- if (!test_and_set_bit(0, &priv->flags)) {
- spin_unlock_irqrestore(&priv->lock, flags);
- disable_irq(dev_info->irq);
- }
+ if (!__test_and_set_bit(UIO_IRQ_DISABLED, &priv->flags))
+ disable_irq_nosync(dev_info->irq);
}
+ spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
+static void uio_dmem_genirq_pm_disable(void *data)
+{
+ struct device *dev = data;
+
+ pm_runtime_disable(dev);
+}
+
static int uio_dmem_genirq_probe(struct platform_device *pdev)
{
struct uio_dmem_genirq_pdata *pdata = dev_get_platdata(&pdev->dev);
@@ -153,36 +160,40 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
if (pdev->dev.of_node) {
/* alloc uioinfo for one device */
- uioinfo = kzalloc(sizeof(*uioinfo), GFP_KERNEL);
+ uioinfo = devm_kzalloc(&pdev->dev, sizeof(*uioinfo), GFP_KERNEL);
if (!uioinfo) {
- ret = -ENOMEM;
dev_err(&pdev->dev, "unable to kmalloc\n");
- goto bad2;
+ return -ENOMEM;
}
uioinfo->name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn",
pdev->dev.of_node);
+ if (!uioinfo->name)
+ return -ENOMEM;
uioinfo->version = "devicetree";
}
if (!uioinfo || !uioinfo->name || !uioinfo->version) {
dev_err(&pdev->dev, "missing platform_data\n");
- goto bad0;
+ return -EINVAL;
}
if (uioinfo->handler || uioinfo->irqcontrol ||
uioinfo->irq_flags & IRQF_SHARED) {
dev_err(&pdev->dev, "interrupt configuration error\n");
- goto bad0;
+ return -EINVAL;
}
- priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv) {
- ret = -ENOMEM;
dev_err(&pdev->dev, "unable to kmalloc\n");
- goto bad0;
+ return -ENOMEM;
}
- dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+ ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+ if (ret) {
+ dev_err(&pdev->dev, "DMA enable failed\n");
+ return ret;
+ }
priv->uioinfo = uioinfo;
spin_lock_init(&priv->lock);
@@ -196,9 +207,24 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
if (ret == -ENXIO && pdev->dev.of_node)
ret = UIO_IRQ_NONE;
else if (ret < 0)
- goto bad1;
+ return ret;
uioinfo->irq = ret;
}
+
+ if (uioinfo->irq) {
+ /*
+ * If a level interrupt, dont do lazy disable. Otherwise the
+ * irq will fire again since clearing of the actual cause, on
+ * device level, is done in userspace
+ * irqd_is_level_type() isn't used since isn't valid until
+ * irq is configured.
+ */
+ if (irq_get_trigger_type(uioinfo->irq) & IRQ_TYPE_LEVEL_MASK) {
+ dev_dbg(&pdev->dev, "disable lazy unmask\n");
+ irq_set_status_flags(uioinfo->irq, IRQ_DISABLE_UNLAZY);
+ }
+ }
+
uiomem = &uioinfo->mem[0];
for (i = 0; i < pdev->num_resources; ++i) {
@@ -230,7 +256,8 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
" dynamic and fixed memory regions.\n");
break;
}
- uiomem->memtype = UIO_MEM_PHYS;
+ uiomem->memtype = UIO_MEM_DMA_COHERENT;
+ uiomem->dma_device = &pdev->dev;
uiomem->addr = DMEM_MAP_ERROR;
uiomem->size = pdata->dynamic_region_sizes[i];
++uiomem;
@@ -263,65 +290,13 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
*/
pm_runtime_enable(&pdev->dev);
- ret = uio_register_device(&pdev->dev, priv->uioinfo);
- if (ret) {
- dev_err(&pdev->dev, "unable to register uio device\n");
- pm_runtime_disable(&pdev->dev);
- goto bad1;
- }
+ ret = devm_add_action_or_reset(&pdev->dev, uio_dmem_genirq_pm_disable, &pdev->dev);
+ if (ret)
+ return ret;
- platform_set_drvdata(pdev, priv);
- return 0;
- bad1:
- kfree(priv);
- bad0:
- /* kfree uioinfo for OF */
- if (pdev->dev.of_node)
- kfree(uioinfo);
- bad2:
- return ret;
+ return devm_uio_register_device(&pdev->dev, priv->uioinfo);
}
-static int uio_dmem_genirq_remove(struct platform_device *pdev)
-{
- struct uio_dmem_genirq_platdata *priv = platform_get_drvdata(pdev);
-
- uio_unregister_device(priv->uioinfo);
- pm_runtime_disable(&pdev->dev);
-
- priv->uioinfo->handler = NULL;
- priv->uioinfo->irqcontrol = NULL;
-
- /* kfree uioinfo for OF */
- if (pdev->dev.of_node)
- kfree(priv->uioinfo);
-
- kfree(priv);
- return 0;
-}
-
-static int uio_dmem_genirq_runtime_nop(struct device *dev)
-{
- /* Runtime PM callback shared between ->runtime_suspend()
- * and ->runtime_resume(). Simply returns success.
- *
- * In this driver pm_runtime_get_sync() and pm_runtime_put_sync()
- * are used at open() and release() time. This allows the
- * Runtime PM code to turn off power to the device while the
- * device is unused, ie before open() and after release().
- *
- * This Runtime PM callback does not need to save or restore
- * any registers since user space is responsbile for hardware
- * register reinitialization after open().
- */
- return 0;
-}
-
-static const struct dev_pm_ops uio_dmem_genirq_dev_pm_ops = {
- .runtime_suspend = uio_dmem_genirq_runtime_nop,
- .runtime_resume = uio_dmem_genirq_runtime_nop,
-};
-
#ifdef CONFIG_OF
static const struct of_device_id uio_of_genirq_match[] = {
{ /* empty for now */ },
@@ -331,10 +306,8 @@ MODULE_DEVICE_TABLE(of, uio_of_genirq_match);
static struct platform_driver uio_dmem_genirq = {
.probe = uio_dmem_genirq_probe,
- .remove = uio_dmem_genirq_remove,
.driver = {
.name = DRIVER_NAME,
- .pm = &uio_dmem_genirq_dev_pm_ops,
.of_match_table = of_match_ptr(uio_of_genirq_match),
},
};