On 25/04/16 16:58, Sricharan R wrote:
From: Laurent Pinchart <[email protected]>
Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet.
Signed-off-by: Laurent Pinchart <[email protected]>
---
drivers/base/platform.c | 13 +++++++++++++
drivers/of/platform.c | 7 +++----
2 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index f437afa..17e64a4 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -557,6 +557,12 @@ static int platform_drv_probe(struct device *_dev)
if (ret < 0)
return ret;
+ if (of_have_populated_dt()) {
+ ret = of_dma_configure_ops(_dev, _dev->of_node);
+ if (ret < 0)
+ goto done;
+ }
+
ret = dev_pm_domain_attach(_dev, true);
if (ret != -EPROBE_DEFER) {
if (drv->probe) {
@@ -569,6 +575,11 @@ static int platform_drv_probe(struct device *_dev)
}
}
+ if (of_have_populated_dt()) {
+ if (ret)
+ of_dma_deconfigure(_dev);
+ }
+done:
if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
dev_warn(_dev, "probe deferral not supported\n");
ret = -ENXIO;
@@ -591,6 +602,8 @@ static int platform_drv_remove(struct device *_dev)
if (drv->remove)
ret = drv->remove(dev);
dev_pm_domain_detach(_dev, true);
+ if (of_have_populated_dt())
+ of_dma_deconfigure(_dev);
return ret;
}
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 17ee8d5..12bbc8e1 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -180,11 +180,9 @@ static struct platform_device
*of_platform_device_create_pdata(
dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;
of_dma_configure_masks(&dev->dev, dev->dev.of_node);
- of_dma_configure_ops(&dev->dev, dev->dev.of_node);
of_msi_configure(&dev->dev, dev->dev.of_node);
if (of_device_add(dev) != 0) {
- of_dma_deconfigure(&dev->dev);
platform_device_put(dev);
goto err_clear_flag;
}
@@ -481,11 +479,12 @@ static int of_platform_device_destroy(struct device *dev,
void *data)
if (dev->bus == &platform_bus_type)
platform_device_unregister(to_platform_device(dev));
#ifdef CONFIG_ARM_AMBA
- else if (dev->bus == &amba_bustype)
+ else if (dev->bus == &amba_bustype) {
amba_device_unregister(to_amba_device(dev));
+ of_dma_deconfigure(dev);
+ }
Note that we definitely need this to happen properly on other buses,
too. I had something for the AMBA bus back when I last looked at
this[0], but since then we now have PCI devices going through the
of_dma_configure() path as well (hence 226d89cbb242).
There's also now some initial ACPI code in flight[1], so it's probably
about time to take another closer look at how this can be properly
generalised, but I'm not necessarily averse to starting with a
DT-focused solution that gets at least half way, then building on top of
that.
Robin.
[0]:http://www.linux-arm.org/git?p=linux-rm.git;a=commitdiff;h=1f38b62b05e17ccbfcc68e4229c69fee74922e2a
[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/13046
#endif
- of_dma_deconfigure(dev);
of_node_clear_flag(dev->of_node, OF_POPULATED);
of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
return 0;
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