dma: dw: split driver to library part and platform code

To simplify the driver development let's split driver to library and platform
code parts. It helps us to add PCI driver in future.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[Fixed compile error and few checkpatch issues]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/Makefile

@@ -15,7 +15,7 @@ obj-$(CONFIG_FSL_DMA) += fsldma.o
 obj-$(CONFIG_MPC512X_DMA) += mpc512x_dma.o
 obj-$(CONFIG_PPC_BESTCOMM) += bestcomm/
 obj-$(CONFIG_MV_XOR) += mv_xor.o
-obj-$(CONFIG_DW_DMAC) += dw/
+obj-$(CONFIG_DW_DMAC_CORE) += dw/
 obj-$(CONFIG_AT_HDMAC) += at_hdmac.o
 obj-$(CONFIG_MX3_IPU) += ipu/
 obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o

drivers/dma/dw/Kconfig

@@ -2,10 +2,14 @@
 # DMA engine configuration for dw
 #
 
-config DW_DMAC
+config DW_DMAC_CORE
 	tristate "Synopsys DesignWare AHB DMA support"
 	depends on GENERIC_HARDIRQS
 	select DMA_ENGINE
+
+config DW_DMAC
+	tristate "Synopsys DesignWare AHB DMA platform driver"
+	select DW_DMAC_CORE
 	default y if CPU_AT32AP7000
 	help
 	  Support the Synopsys DesignWare AHB DMA controller. This
@@ -14,7 +18,7 @@ config DW_DMAC
 config DW_DMAC_BIG_ENDIAN_IO
 	bool "Use big endian I/O register access"
 	default y if AVR32
-	depends on DW_DMAC
+	depends on DW_DMAC_CORE
 	help
 	  Say yes here to use big endian I/O access when reading and writing
 	  to the DMA controller registers. This is needed on some platforms,

drivers/dma/dw/Makefile

-obj-$(CONFIG_DW_DMAC) += dw_dmac.o
+obj-$(CONFIG_DW_DMAC_CORE)	+= dw_dmac_core.o
+dw_dmac_core-objs	:= core.o
+
+obj-$(CONFIG_DW_DMAC)		+= dw_dmac.o
+dw_dmac-objs		:= platform.o

drivers/dma/dw/internal.h

+/*
+ * Driver for the Synopsys DesignWare DMA Controller
+ *
+ * Copyright (C) 2013 Intel Corporation
+ *
+ * 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.
+ */
+
+#ifndef _DW_DMAC_INTERNAL_H
+#define _DW_DMAC_INTERNAL_H
+
+#include <linux/device.h>
+#include <linux/dw_dmac.h>
+
+#include "regs.h"
+
+/**
+ * struct dw_dma_chip - representation of DesignWare DMA controller hardware
+ * @dev:		struct device of the DMA controller
+ * @irq:		irq line
+ * @regs:		memory mapped I/O space
+ * @dw:			struct dw_dma that is filed by dw_dma_probe()
+ */
+struct dw_dma_chip {
+	struct device	*dev;
+	int		irq;
+	void __iomem	*regs;
+	struct dw_dma	*dw;
+};
+
+/* Export to the platform drivers */
+int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata);
+int dw_dma_remove(struct dw_dma_chip *chip);
+
+void dw_dma_shutdown(struct dw_dma_chip *chip);
+
+#ifdef CONFIG_PM_SLEEP
+
+int dw_dma_suspend(struct dw_dma_chip *chip);
+int dw_dma_resume(struct dw_dma_chip *chip);
+
+#endif /* CONFIG_PM_SLEEP */
+
+/**
+ * dwc_get_dms - get destination master
+ * @slave:	pointer to the custom slave configuration
+ *
+ * Returns destination master in the custom slave configuration if defined, or
+ * default value otherwise.
+ */
+static inline unsigned int dwc_get_dms(struct dw_dma_slave *slave)
+{
+	return slave ? slave->dst_master : 0;
+}
+
+/**
+ * dwc_get_sms - get source master
+ * @slave:	pointer to the custom slave configuration
+ *
+ * Returns source master in the custom slave configuration if defined, or
+ * default value otherwise.
+ */
+static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
+{
+	return slave ? slave->src_master : 1;
+}
+
+#endif /* _DW_DMAC_INTERNAL_H */

drivers/dma/dw/platform.c

+/*
+ * 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/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"
+
+struct dw_dma_of_filter_args {
+	struct dw_dma *dw;
+	unsigned int req;
+	unsigned int src;
+	unsigned int dst;
+};
+
+static bool dw_dma_of_filter(struct dma_chan *chan, void *param)
+{
+	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+	struct dw_dma_of_filter_args *fargs = param;
+
+	/* Ensure the device matches our channel */
+	if (chan->device != &fargs->dw->dma)
+		return false;
+
+	dwc->request_line = fargs->req;
+	dwc->src_master	= fargs->src;
+	dwc->dst_master	= fargs->dst;
+
+	return true;
+}
+
+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_of_filter_args fargs = {
+		.dw = dw,
+	};
+	dma_cap_mask_t cap;
+
+	if (dma_spec->args_count != 3)
+		return NULL;
+
+	fargs.req = dma_spec->args[0];
+	fargs.src = dma_spec->args[1];
+	fargs.dst = dma_spec->args[2];
+
+	if (WARN_ON(fargs.req >= DW_DMA_MAX_NR_REQUESTS ||
+		    fargs.src >= dw->nr_masters ||
+		    fargs.dst >= 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_of_filter, &fargs);
+}
+
+#ifdef CONFIG_ACPI
+static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
+{
+	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+	struct acpi_dma_spec *dma_spec = param;
+
+	if (chan->device->dev != dma_spec->dev ||
+	    chan->chan_id != dma_spec->chan_id)
+		return false;
+
+	dwc->request_line = dma_spec->slave_id;
+	dwc->src_master = dwc_get_sms(NULL);
+	dwc->dst_master = dwc_get_dms(NULL);
+
+	return true;
+}
+
+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[4];
+
+	if (!np) {
+		dev_err(&pdev->dev, "Missing DT data\n");
+		return NULL;
+	}
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return NULL;
+
+	if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
+		return NULL;
+
+	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 > 4)
+			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);
+
+	/* Apply default dma_mask if needed */
+	if (!dev->dma_mask) {
+		dev->dma_mask = &dev->coherent_dma_mask;
+		dev->coherent_dma_mask = DMA_BIT_MASK(32);
+	}
+
+	pdata = dev_get_platdata(dev);
+	if (!pdata)
+		pdata = dw_dma_parse_dt(pdev);
+
+	chip->dev = dev;
+
+	err = dw_dma_probe(chip, pdata);
+	if (err)
+		return err;
+
+	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;
+}
+
+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);
+
+	return dw_dma_remove(chip);
+}
+
+static void dw_shutdown(struct platform_device *pdev)
+{
+	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
+
+	dw_dma_shutdown(chip);
+}
+
+#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 },
+	{ }
+};
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+
+static int dw_suspend_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
+
+	return dw_dma_suspend(chip);
+}
+
+static int dw_resume_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
+
+	return dw_dma_resume(chip);
+}
+
+#else /* !CONFIG_PM_SLEEP */
+
+#define dw_suspend_noirq	NULL
+#define dw_resume_noirq		NULL
+
+#endif /* !CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops dw_dev_pm_ops = {
+	.suspend_noirq = dw_suspend_noirq,
+	.resume_noirq = dw_resume_noirq,
+	.freeze_noirq = dw_suspend_noirq,
+	.thaw_noirq = dw_resume_noirq,
+	.restore_noirq = dw_resume_noirq,
+	.poweroff_noirq = dw_suspend_noirq,
+};
+
+static struct platform_driver dw_driver = {
+	.probe		= dw_probe,
+	.remove		= dw_remove,
+	.shutdown	= dw_shutdown,
+	.driver = {
+		.name	= "dw_dmac",
+		.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");

drivers/dma/dw/dw_dmac_regs.h → drivers/dma/dw/regs.h

@@ -9,6 +9,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/interrupt.h>
 #include <linux/dmaengine.h>
 #include <linux/dw_dmac.h>