[PATCH V10 7/7] dma: qcom_hidma: add support for object hierarchy
Sinan Kaya
okaya at codeaurora.org
Thu Dec 17 09:01:22 PST 2015
In order to create a relationship model between the channels and the
management object, we are adding support for object hierarchy to the
drivers. This patch simplifies the userspace application development.
We will not have to traverse different firmware paths based on device
tree or ACPI baed kernels.
No matter what flavor of kernel is used, objects will be represented as
platform devices.
The new layout is as follows:
hidmam_10: hidma-mgmt at 0x5A000000 {
compatible = "qcom,hidma-mgmt-1.0";
...
hidma_10: hidma at 0x5a010000 {
compatible = "qcom,hidma-1.0";
...
}
}
The hidma_mgmt_init detects each instance of the hidma-mgmt-1.0 objects
in device tree and calls into the channel driver to create platform devices
for each child of the management object.
Signed-off-by: Sinan Kaya <okaya at codeaurora.org>
---
Documentation/ABI/testing/sysfs-platform-hidma | 9 +++
drivers/dma/qcom/hidma.c | 39 +++++++++-
drivers/dma/qcom/hidma_mgmt.c | 103 ++++++++++++++++++++++++-
3 files changed, 147 insertions(+), 4 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-platform-hidma
diff --git a/Documentation/ABI/testing/sysfs-platform-hidma b/Documentation/ABI/testing/sysfs-platform-hidma
new file mode 100644
index 0000000..d364415
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-platform-hidma
@@ -0,0 +1,9 @@
+What: /sys/devices/platform/hidma-*/chid
+ /sys/devices/platform/QCOM8061:*/chid
+Date: Dec 2015
+KernelVersion: 4.4
+Contact: "Sinan Kaya <okaya at cudeaurora.org>"
+Description:
+ Contains the ID of the channel within the HIDMA instance.
+ It is used to associate a given HIDMA channel with the
+ priority and weight calls in the management interface.
diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
index 833db9e..ac20bdb 100644
--- a/drivers/dma/qcom/hidma.c
+++ b/drivers/dma/qcom/hidma.c
@@ -549,6 +549,43 @@ static irqreturn_t hidma_chirq_handler(int chirq, void *arg)
return hidma_ll_inthandler(chirq, lldev);
}
+static ssize_t hidma_show_values(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct hidma_dev *mdev = platform_get_drvdata(pdev);
+
+ buf[0] = 0;
+
+ if (strcmp(attr->attr.name, "chid") == 0)
+ sprintf(buf, "%d\n", mdev->chidx);
+
+ return strlen(buf);
+}
+
+static int hidma_create_sysfs_entry(struct hidma_dev *dev, char *name,
+ int mode)
+{
+ struct device_attribute *attrs;
+ char *name_copy;
+
+ attrs = devm_kmalloc(dev->ddev.dev, sizeof(struct device_attribute),
+ GFP_KERNEL);
+ if (!attrs)
+ return -ENOMEM;
+
+ name_copy = devm_kstrdup(dev->ddev.dev, name, GFP_KERNEL);
+ if (!name_copy)
+ return -ENOMEM;
+
+ attrs->attr.name = name_copy;
+ attrs->attr.mode = mode;
+ attrs->show = hidma_show_values;
+ sysfs_attr_init(&attrs->attr);
+
+ return device_create_file(dev->ddev.dev, attrs);
+}
+
static int hidma_probe(struct platform_device *pdev)
{
struct hidma_dev *dmadev;
@@ -682,6 +719,7 @@ static int hidma_probe(struct platform_device *pdev)
dmadev->irq = chirq;
tasklet_init(&dmadev->task, hidma_issue_task, (unsigned long)dmadev);
hidma_debug_init(dmadev);
+ hidma_create_sysfs_entry(dmadev, "chid", S_IRUGO);
dev_info(&pdev->dev, "HI-DMA engine driver registration complete\n");
platform_set_drvdata(pdev, dmadev);
pm_runtime_mark_last_busy(dmadev->ddev.dev);
@@ -730,7 +768,6 @@ static const struct of_device_id hidma_match[] = {
{.compatible = "qcom,hidma-1.0",},
{},
};
-
MODULE_DEVICE_TABLE(of, hidma_match);
static struct platform_driver hidma_driver = {
diff --git a/drivers/dma/qcom/hidma_mgmt.c b/drivers/dma/qcom/hidma_mgmt.c
index ef491b8..d387338 100644
--- a/drivers/dma/qcom/hidma_mgmt.c
+++ b/drivers/dma/qcom/hidma_mgmt.c
@@ -17,13 +17,14 @@
#include <linux/acpi.h>
#include <linux/of.h>
#include <linux/property.h>
-#include <linux/interrupt.h>
-#include <linux/platform_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
#include "hidma_mgmt.h"
@@ -298,5 +299,101 @@ static struct platform_driver hidma_mgmt_driver = {
},
};
-module_platform_driver(hidma_mgmt_driver);
+#ifdef CONFIG_OF
+static int object_counter;
+
+static int __init hidma_mgmt_of_populate_channels(struct device_node *np)
+{
+ struct platform_device *pdev_parent = of_find_device_by_node(np);
+ struct platform_device_info pdevinfo;
+ struct of_phandle_args out_irq;
+ struct device_node *child;
+ struct resource *res;
+ const __be32 *cell;
+ int ret = 0, size, i, num;
+ u64 addr, addr_size;
+
+ for_each_available_child_of_node(np, child) {
+ int iter = 0;
+
+ cell = of_get_property(child, "reg", &size);
+ if (!cell) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ size /= (sizeof(*cell));
+ num = size /
+ (of_n_addr_cells(child) + of_n_size_cells(child)) + 1;
+
+ /* allocate a resource array */
+ res = kcalloc(num, sizeof(*res), GFP_KERNEL);
+ if (!res) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* read each reg value */
+ i = 0;
+ while (i < size) {
+ addr = of_read_number(&cell[i],
+ of_n_addr_cells(child));
+ i += of_n_addr_cells(child);
+
+ addr_size = of_read_number(&cell[i],
+ of_n_size_cells(child));
+ i += of_n_size_cells(child);
+
+ res[iter].start = addr;
+ res[iter].end = res[iter].start + addr_size - 1;
+ res[iter].flags = IORESOURCE_MEM;
+ iter++;
+ }
+
+ ret = of_irq_parse_one(child, 0, &out_irq);
+ if (ret)
+ goto out;
+
+ res[iter].start = irq_create_of_mapping(&out_irq);
+ res[iter].name = "hidma event irq";
+ res[iter].flags = IORESOURCE_IRQ;
+
+ pdevinfo.fwnode = &child->fwnode;
+ pdevinfo.parent = pdev_parent ? &pdev_parent->dev : NULL;
+ pdevinfo.name = child->name;
+ pdevinfo.id = object_counter++;
+ pdevinfo.res = res;
+ pdevinfo.num_res = num;
+ pdevinfo.data = NULL;
+ pdevinfo.size_data = 0;
+ pdevinfo.dma_mask = DMA_BIT_MASK(64);
+ platform_device_register_full(&pdevinfo);
+
+ kfree(res);
+ res = NULL;
+ }
+out:
+ kfree(res);
+
+ return ret;
+}
+#endif
+
+static int __init hidma_mgmt_init(void)
+{
+#ifdef CONFIG_OF
+ struct device_node *child;
+
+ for (child = of_find_matching_node(NULL, hidma_mgmt_match); child;
+ child = of_find_matching_node(child, hidma_mgmt_match)) {
+ /* device tree based firmware here */
+ hidma_mgmt_of_populate_channels(child);
+ of_node_put(child);
+ }
+#endif
+ platform_driver_register(&hidma_mgmt_driver);
+
+ return 0;
+}
+module_init(hidma_mgmt_init);
MODULE_LICENSE("GPL v2");
--
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
More information about the linux-arm-kernel
mailing list