drivers/dma/dw/platform.c - kernel/quantenna - Git at Google

 /*
  * Platform driver for the Synopsys DesignWare DMA Controller
  *
  * Copyright (C) 2007-2008 Atmel Corporation
  * Copyright (C) 2010-2011 ST Microelectronics
  * Copyright (C) 2013 Intel Corporation
  *
  * Some parts of this driver are derived from the original dw_dmac.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/module.h>
 #include <linux/device.h>
 #include <linux/clk.h>
 #include <linux/pm_runtime.h>
 #include <linux/platform_device.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/of.h>
 #include <linux/of_dma.h>
 #include <linux/acpi.h>
 #include <linux/acpi_dma.h>

 #include "internal.h"

 #define DRV_NAME	"dw_dmac"

 static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
 					struct of_dma *ofdma)
 {
 	struct dw_dma *dw = ofdma->of_dma_data;
 	struct dw_dma_slave slave = {
 		.dma_dev = dw->dma.dev,
 	};
 	dma_cap_mask_t cap;

 	if (dma_spec->args_count != 3)
 		return NULL;

 	slave.src_id = dma_spec->args[0];
 	slave.dst_id = dma_spec->args[0];
 	slave.src_master = dma_spec->args[1];
 	slave.dst_master = dma_spec->args[2];

 	if (WARN_ON(slave.src_id >= DW_DMA_MAX_NR_REQUESTS ||
 		    slave.dst_id >= DW_DMA_MAX_NR_REQUESTS ||
 		    slave.src_master >= dw->nr_masters ||
 		    slave.dst_master >= dw->nr_masters))
 		return NULL;

 	dma_cap_zero(cap);
 	dma_cap_set(DMA_SLAVE, cap);

 	/* TODO: there should be a simpler way to do this */
 	return dma_request_channel(cap, dw_dma_filter, &slave);
 }

 #ifdef CONFIG_ACPI
 static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
 {
 	struct acpi_dma_spec *dma_spec = param;
 	struct dw_dma_slave slave = {
 		.dma_dev = dma_spec->dev,
 		.src_id = dma_spec->slave_id,
 		.dst_id = dma_spec->slave_id,
 		.src_master = 1,
 		.dst_master = 0,
 	};

 	return dw_dma_filter(chan, &slave);
 }

 static void dw_dma_acpi_controller_register(struct dw_dma *dw)
 {
 	struct device *dev = dw->dma.dev;
 	struct acpi_dma_filter_info *info;
 	int ret;

 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
 	if (!info)
 		return;

 	dma_cap_zero(info->dma_cap);
 	dma_cap_set(DMA_SLAVE, info->dma_cap);
 	info->filter_fn = dw_dma_acpi_filter;

 	ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
 						info);
 	if (ret)
 		dev_err(dev, "could not register acpi_dma_controller\n");
 }
 #else /* !CONFIG_ACPI */
 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
 #endif /* !CONFIG_ACPI */

 #ifdef CONFIG_OF
 static struct dw_dma_platform_data *
 dw_dma_parse_dt(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct dw_dma_platform_data *pdata;
 	u32 tmp, arr[DW_DMA_MAX_NR_MASTERS];
 	u32 nr_channels;

 	if (!np) {
 		dev_err(&pdev->dev, "Missing DT data\n");
 		return NULL;
 	}

 	if (of_property_read_u32(np, "dma-channels", &nr_channels))
 		return NULL;

 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
 		return NULL;

 	pdata->nr_channels = nr_channels;

 	if (of_property_read_bool(np, "is_private"))
 		pdata->is_private = true;

 	if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
 		pdata->chan_allocation_order = (unsigned char)tmp;

 	if (!of_property_read_u32(np, "chan_priority", &tmp))
 		pdata->chan_priority = tmp;

 	if (!of_property_read_u32(np, "block_size", &tmp))
 		pdata->block_size = tmp;

 	if (!of_property_read_u32(np, "dma-masters", &tmp)) {
 		if (tmp > DW_DMA_MAX_NR_MASTERS)
 			return NULL;

 		pdata->nr_masters = tmp;
 	}

 	if (!of_property_read_u32_array(np, "data_width", arr,
 				pdata->nr_masters))
 		for (tmp = 0; tmp < pdata->nr_masters; tmp++)
 			pdata->data_width[tmp] = arr[tmp];

 	return pdata;
 }
 #else
 static inline struct dw_dma_platform_data *
 dw_dma_parse_dt(struct platform_device *pdev)
 {
 	return NULL;
 }
 #endif

 static int dw_probe(struct platform_device *pdev)
 {
 	struct dw_dma_chip *chip;
 	struct device *dev = &pdev->dev;
 	struct resource *mem;
 	struct dw_dma_platform_data *pdata;
 	int err;

 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;

 	chip->irq = platform_get_irq(pdev, 0);
 	if (chip->irq < 0)
 		return chip->irq;

 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	chip->regs = devm_ioremap_resource(dev, mem);
 	if (IS_ERR(chip->regs))
 		return PTR_ERR(chip->regs);

 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 	if (err)
 		return err;

 	pdata = dev_get_platdata(dev);
 	if (!pdata)
 		pdata = dw_dma_parse_dt(pdev);

 	chip->dev = dev;

 	chip->clk = devm_clk_get(chip->dev, "hclk");
 	if (IS_ERR(chip->clk))
 		return PTR_ERR(chip->clk);
 	err = clk_prepare_enable(chip->clk);
 	if (err)
 		return err;

 	pm_runtime_enable(&pdev->dev);

 	err = dw_dma_probe(chip, pdata);
 	if (err)
 		goto err_dw_dma_probe;

 	platform_set_drvdata(pdev, chip);

 	if (pdev->dev.of_node) {
 		err = of_dma_controller_register(pdev->dev.of_node,
 						 dw_dma_of_xlate, chip->dw);
 		if (err)
 			dev_err(&pdev->dev,
 				"could not register of_dma_controller\n");
 	}

 	if (ACPI_HANDLE(&pdev->dev))
 		dw_dma_acpi_controller_register(chip->dw);

 	return 0;

 err_dw_dma_probe:
 	pm_runtime_disable(&pdev->dev);
 	clk_disable_unprepare(chip->clk);
 	return err;
 }

 static int dw_remove(struct platform_device *pdev)
 {
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

 	if (pdev->dev.of_node)
 		of_dma_controller_free(pdev->dev.of_node);

 	dw_dma_remove(chip);
 	pm_runtime_disable(&pdev->dev);
 	clk_disable_unprepare(chip->clk);

 	return 0;
 }

 static void dw_shutdown(struct platform_device *pdev)
 {
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

 	/*
 	 * We have to call dw_dma_disable() to stop any ongoing transfer. On
 	 * some platforms we can't do that since DMA device is powered off.
 	 * Moreover we have no possibility to check if the platform is affected
 	 * or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
 	 * unconditionally. On the other hand we can't use
 	 * pm_runtime_suspended() because runtime PM framework is not fully
 	 * used by the driver.
 	 */
 	pm_runtime_get_sync(chip->dev);
 	dw_dma_disable(chip);
 	pm_runtime_put_sync_suspend(chip->dev);

 	clk_disable_unprepare(chip->clk);
 }

 #ifdef CONFIG_OF
 static const struct of_device_id dw_dma_of_id_table[] = {
 	{ .compatible = "snps,dma-spear1340" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
 #endif

 #ifdef CONFIG_ACPI
 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
 	{ "INTL9C60", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
 #endif

 #ifdef CONFIG_PM_SLEEP

 static int dw_suspend_late(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

 	dw_dma_disable(chip);
 	clk_disable_unprepare(chip->clk);

 	return 0;
 }

 static int dw_resume_early(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

 	clk_prepare_enable(chip->clk);
 	return dw_dma_enable(chip);
 }

 #endif /* CONFIG_PM_SLEEP */

 static const struct dev_pm_ops dw_dev_pm_ops = {
 	SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
 };

 static struct platform_driver dw_driver = {
 	.probe		= dw_probe,
 	.remove		= dw_remove,
 	.shutdown       = dw_shutdown,
 	.driver = {
 		.name	= DRV_NAME,
 		.pm	= &dw_dev_pm_ops,
 		.of_match_table = of_match_ptr(dw_dma_of_id_table),
 		.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
 	},
 };

 static int __init dw_init(void)
 {
 	return platform_driver_register(&dw_driver);
 }
 subsys_initcall(dw_init);

 static void __exit dw_exit(void)
 {
 	platform_driver_unregister(&dw_driver);
 }
 module_exit(dw_exit);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
 MODULE_ALIAS("platform:" DRV_NAME);
	/*
	* Platform driver for the Synopsys DesignWare DMA Controller
	*
	* Copyright (C) 2007-2008 Atmel Corporation
	* Copyright (C) 2010-2011 ST Microelectronics
	* Copyright (C) 2013 Intel Corporation
	*
	* Some parts of this driver are derived from the original dw_dmac.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/module.h>
	#include <linux/device.h>
	#include <linux/clk.h>
	#include <linux/pm_runtime.h>
	#include <linux/platform_device.h>
	#include <linux/dmaengine.h>
	#include <linux/dma-mapping.h>
	#include <linux/of.h>
	#include <linux/of_dma.h>
	#include <linux/acpi.h>
	#include <linux/acpi_dma.h>

	#include "internal.h"

	#define DRV_NAME "dw_dmac"

	static struct dma_chan dw_dma_of_xlate(struct of_phandle_args dma_spec,
	struct of_dma *ofdma)
	{
	struct dw_dma *dw = ofdma->of_dma_data;
	struct dw_dma_slave slave = {
	.dma_dev = dw->dma.dev,
	};
	dma_cap_mask_t cap;

	if (dma_spec->args_count != 3)
	return NULL;

	slave.src_id = dma_spec->args[0];
	slave.dst_id = dma_spec->args[0];
	slave.src_master = dma_spec->args[1];
	slave.dst_master = dma_spec->args[2];

	if (WARN_ON(slave.src_id >= DW_DMA_MAX_NR_REQUESTS \|\|
	slave.dst_id >= DW_DMA_MAX_NR_REQUESTS \|\|
	slave.src_master >= dw->nr_masters \|\|
	slave.dst_master >= dw->nr_masters))
	return NULL;

	dma_cap_zero(cap);
	dma_cap_set(DMA_SLAVE, cap);

	/* TODO: there should be a simpler way to do this */
	return dma_request_channel(cap, dw_dma_filter, &slave);
	}

	#ifdef CONFIG_ACPI
	static bool dw_dma_acpi_filter(struct dma_chan chan, void param)
	{
	struct acpi_dma_spec *dma_spec = param;
	struct dw_dma_slave slave = {
	.dma_dev = dma_spec->dev,
	.src_id = dma_spec->slave_id,
	.dst_id = dma_spec->slave_id,
	.src_master = 1,
	.dst_master = 0,
	};

	return dw_dma_filter(chan, &slave);
	}

	static void dw_dma_acpi_controller_register(struct dw_dma *dw)
	{
	struct device *dev = dw->dma.dev;
	struct acpi_dma_filter_info *info;
	int ret;

	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
	if (!info)
	return;

	dma_cap_zero(info->dma_cap);
	dma_cap_set(DMA_SLAVE, info->dma_cap);
	info->filter_fn = dw_dma_acpi_filter;

	ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
	info);
	if (ret)
	dev_err(dev, "could not register acpi_dma_controller\n");
	}
	#else /* !CONFIG_ACPI */
	static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
	#endif /* !CONFIG_ACPI */

	#ifdef CONFIG_OF
	static struct dw_dma_platform_data *
	dw_dma_parse_dt(struct platform_device *pdev)
	{
	struct device_node *np = pdev->dev.of_node;
	struct dw_dma_platform_data *pdata;
	u32 tmp, arr[DW_DMA_MAX_NR_MASTERS];
	u32 nr_channels;

	if (!np) {
	dev_err(&pdev->dev, "Missing DT data\n");
	return NULL;
	}

	if (of_property_read_u32(np, "dma-channels", &nr_channels))
	return NULL;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
	return NULL;

	pdata->nr_channels = nr_channels;

	if (of_property_read_bool(np, "is_private"))
	pdata->is_private = true;

	if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
	pdata->chan_allocation_order = (unsigned char)tmp;

	if (!of_property_read_u32(np, "chan_priority", &tmp))
	pdata->chan_priority = tmp;

	if (!of_property_read_u32(np, "block_size", &tmp))
	pdata->block_size = tmp;

	if (!of_property_read_u32(np, "dma-masters", &tmp)) {
	if (tmp > DW_DMA_MAX_NR_MASTERS)
	return NULL;

	pdata->nr_masters = tmp;
	}

	if (!of_property_read_u32_array(np, "data_width", arr,
	pdata->nr_masters))
	for (tmp = 0; tmp < pdata->nr_masters; tmp++)
	pdata->data_width[tmp] = arr[tmp];

	return pdata;
	}
	#else
	static inline struct dw_dma_platform_data *
	dw_dma_parse_dt(struct platform_device *pdev)
	{
	return NULL;
	}
	#endif

	static int dw_probe(struct platform_device *pdev)
	{
	struct dw_dma_chip *chip;
	struct device *dev = &pdev->dev;
	struct resource *mem;
	struct dw_dma_platform_data *pdata;
	int err;

	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
	if (!chip)
	return -ENOMEM;

	chip->irq = platform_get_irq(pdev, 0);
	if (chip->irq < 0)
	return chip->irq;

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	chip->regs = devm_ioremap_resource(dev, mem);
	if (IS_ERR(chip->regs))
	return PTR_ERR(chip->regs);

	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
	if (err)
	return err;

	pdata = dev_get_platdata(dev);
	if (!pdata)
	pdata = dw_dma_parse_dt(pdev);

	chip->dev = dev;

	chip->clk = devm_clk_get(chip->dev, "hclk");
	if (IS_ERR(chip->clk))
	return PTR_ERR(chip->clk);
	err = clk_prepare_enable(chip->clk);
	if (err)
	return err;

	pm_runtime_enable(&pdev->dev);

	err = dw_dma_probe(chip, pdata);
	if (err)
	goto err_dw_dma_probe;

	platform_set_drvdata(pdev, chip);

	if (pdev->dev.of_node) {
	err = of_dma_controller_register(pdev->dev.of_node,
	dw_dma_of_xlate, chip->dw);
	if (err)
	dev_err(&pdev->dev,
	"could not register of_dma_controller\n");
	}

	if (ACPI_HANDLE(&pdev->dev))
	dw_dma_acpi_controller_register(chip->dw);

	return 0;

	err_dw_dma_probe:
	pm_runtime_disable(&pdev->dev);
	clk_disable_unprepare(chip->clk);
	return err;
	}

	static int dw_remove(struct platform_device *pdev)
	{
	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

	if (pdev->dev.of_node)
	of_dma_controller_free(pdev->dev.of_node);

	dw_dma_remove(chip);
	pm_runtime_disable(&pdev->dev);
	clk_disable_unprepare(chip->clk);

	return 0;
	}

	static void dw_shutdown(struct platform_device *pdev)
	{
	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

	/*
	* We have to call dw_dma_disable() to stop any ongoing transfer. On
	* some platforms we can't do that since DMA device is powered off.
	* Moreover we have no possibility to check if the platform is affected
	* or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
	* unconditionally. On the other hand we can't use
	* pm_runtime_suspended() because runtime PM framework is not fully
	* used by the driver.
	*/
	pm_runtime_get_sync(chip->dev);
	dw_dma_disable(chip);
	pm_runtime_put_sync_suspend(chip->dev);

	clk_disable_unprepare(chip->clk);
	}

	#ifdef CONFIG_OF
	static const struct of_device_id dw_dma_of_id_table[] = {
	{ .compatible = "snps,dma-spear1340" },
	{}
	};
	MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
	#endif

	#ifdef CONFIG_ACPI
	static const struct acpi_device_id dw_dma_acpi_id_table[] = {
	{ "INTL9C60", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
	#endif

	#ifdef CONFIG_PM_SLEEP

	static int dw_suspend_late(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

	dw_dma_disable(chip);
	clk_disable_unprepare(chip->clk);

	return 0;
	}

	static int dw_resume_early(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct dw_dma_chip *chip = platform_get_drvdata(pdev);

	clk_prepare_enable(chip->clk);
	return dw_dma_enable(chip);
	}

	#endif /* CONFIG_PM_SLEEP */

	static const struct dev_pm_ops dw_dev_pm_ops = {
	SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
	};

	static struct platform_driver dw_driver = {
	.probe = dw_probe,
	.remove = dw_remove,
	.shutdown = dw_shutdown,
	.driver = {
	.name = DRV_NAME,
	.pm = &dw_dev_pm_ops,
	.of_match_table = of_match_ptr(dw_dma_of_id_table),
	.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
	},
	};

	static int __init dw_init(void)
	{
	return platform_driver_register(&dw_driver);
	}
	subsys_initcall(dw_init);

	static void __exit dw_exit(void)
	{
	platform_driver_unregister(&dw_driver);
	}
	module_exit(dw_exit);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
	MODULE_ALIAS("platform:" DRV_NAME);