Commit 42d236f8 authored by Sinan Kaya's avatar Sinan Kaya Committed by Vinod Koul
Browse files

dmaengine: qcom_hidma: add support for object hierarchy 



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 based 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@0x5A000000 {
	compatible = "qcom,hidma-mgmt-1.0";
	...

	hidma_10: hidma@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: default avatarSinan Kaya <okaya@codeaurora.org>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent 570d0176

Documentation/ABI/testing/sysfs-platform-hidma

0 → 100644
+9 −0
Original line number Diff line number Diff line 
What:		/sys/devices/platform/hidma-*/chid

		/sys/devices/platform/QCOM8061:*/chid

Date:		Dec 2015

KernelVersion:	4.4

Contact:	"Sinan Kaya <okaya@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.

drivers/dma/qcom/hidma.c

+38 −1
Original line number Diff line number Diff line
@@ -530,6 +530,43 @@ 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;
@@ -645,6 +682,7 @@ 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);
@@ -692,7 +730,6 @@ 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 = {

drivers/dma/qcom/hidma_mgmt.c

+109 −4
Original line number Diff line number Diff line 
/*

 * Qualcomm Technologies HIDMA DMA engine Management interface

 *

 * Copyright (c) 2015, The Linux Foundation. All rights reserved.

 * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and
@@ -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 +299,109 @@ static struct platform_driver hidma_mgmt_driver = { 
	},

};



module_platform_driver(hidma_mgmt_driver);

#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)

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) {

		struct resource *res_iter;

		struct platform_device *new_pdev;



		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;

		res_iter = res;

		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;

			res_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;



		memset(&pdevinfo, 0, sizeof(pdevinfo));

		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);

		new_pdev = platform_device_register_full(&pdevinfo);

		if (!new_pdev) {

			ret = -ENODEV;

			goto out;

		}

		of_dma_configure(&new_pdev->dev, child);



		kfree(res);

		res = NULL;

	}

out:

	kfree(res);



	return ret;

}

#endif



static int __init hidma_mgmt_init(void)

{

#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)

	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");

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