[PATCH V3 4/8] drivers: platform: Configure dma operations at probe time
From: Sricharan R <hidden>
Date: 2016-10-04 17:03:48
Also in:
linux-arm-msm, linux-iommu
Subsystem:
dma mapping helpers, driver core, kobjects, debugfs and sysfs, open firmware and flattened device tree, pci subsystem, the rest · Maintainers:
Marek Szyprowski, Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Rob Herring, Saravana Kannan, Bjorn Helgaas, Linus Torvalds
Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet. The dma_configure for the device is now called
from the generic device_attach callback just before the bus/driver probe
is called. This way, configuring the dma ops for the device would be called
at the same place for all bus_types, hence the deferred probing mechanism
should work for all buses as well.
pci_bus_add_devices (platform/amba)(_device_create/driver_register)
| |
pci_bus_add_device (device_add/driver_register)
| |
device_attach device_initial_probe
| |
__device_attach_driver __device_attach_driver
|
driver_probe_device
|
really_probe
|
dma_configure
Similarly on the device/driver_unregister path __device_release_driver is
called which inturn calls dma_deconfigure.
Signed-off-by: Sricharan R <redacted>
---
drivers/base/dd.c | 10 ++++++++++
drivers/base/dma-mapping.c | 11 +++++++++++
drivers/of/platform.c | 4 ----
drivers/pci/probe.c | 5 +----
include/linux/dma-mapping.h | 3 +++
5 files changed, 25 insertions(+), 8 deletions(-)
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 16688f5..cfebd48 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c@@ -19,6 +19,7 @@ #include <linux/device.h> #include <linux/delay.h> +#include <linux/dma-mapping.h> #include <linux/module.h> #include <linux/kthread.h> #include <linux/wait.h>
@@ -353,6 +354,10 @@ static int really_probe(struct device *dev, struct device_driver *drv) if (ret) goto pinctrl_bind_failed; + ret = dma_configure(dev); + if (ret) + goto dma_failed; + if (driver_sysfs_add(dev)) { printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n", __func__, dev_name(dev));
@@ -395,6 +400,8 @@ static int really_probe(struct device *dev, struct device_driver *drv) goto done; probe_failed: + dma_deconfigure(dev); +dma_failed: if (dev->bus) blocking_notifier_call_chain(&dev->bus->p->bus_notifier, BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
@@ -780,6 +787,9 @@ static void __device_release_driver(struct device *dev) dev->bus->remove(dev); else if (drv->remove) drv->remove(dev); + + dma_deconfigure(dev); + devres_release_all(dev); dev->driver = NULL; dev_set_drvdata(dev, NULL);
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index d799662..54e87f5 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c@@ -10,6 +10,7 @@ #include <linux/dma-mapping.h> #include <linux/export.h> #include <linux/gfp.h> +#include <linux/of_device.h> #include <linux/slab.h> #include <linux/vmalloc.h>
@@ -166,6 +167,16 @@ void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr, } EXPORT_SYMBOL(dmam_free_noncoherent); +int dma_configure(struct device *dev) +{ + return of_dma_configure(dev, dev->of_node); +} + +void dma_deconfigure(struct device *dev) +{ + of_dma_deconfigure(dev); +} + #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT static void dmam_coherent_decl_release(struct device *dev, void *res)
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 9cb7090..adbd77c 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c@@ -181,11 +181,9 @@ static struct platform_device *of_platform_device_create_pdata( dev->dev.bus = &platform_bus_type; dev->dev.platform_data = platform_data; - of_dma_configure(&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; }
@@ -242,7 +240,6 @@ static struct amba_device *of_amba_device_create(struct device_node *node, dev_set_name(&dev->dev, "%s", bus_id); else of_device_make_bus_id(&dev->dev); - of_dma_configure(&dev->dev, dev->dev.of_node); /* Allow the HW Peripheral ID to be overridden */ prop = of_get_property(node, "arm,primecell-periphid", NULL);
@@ -536,7 +533,6 @@ static int of_platform_device_destroy(struct device *dev, void *data) amba_device_unregister(to_amba_device(dev)); #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;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 93f280d..85c9553 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c@@ -1724,10 +1724,7 @@ static void pci_dma_configure(struct pci_dev *dev) { struct device *bridge = pci_get_host_bridge_device(dev); - if (IS_ENABLED(CONFIG_OF) && - bridge->parent && bridge->parent->of_node) { - of_dma_configure(&dev->dev, bridge->parent->of_node); - } else if (has_acpi_companion(bridge)) { + if (has_acpi_companion(bridge)) { struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); enum dev_dma_attr attr = acpi_get_dma_attr(adev);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 66533e1..2766dbe 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h@@ -656,6 +656,9 @@ dma_mark_declared_memory_occupied(struct device *dev, } #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */ +int dma_configure(struct device *dev); +void dma_deconfigure(struct device *dev); + /* * Managed DMA API */
--
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