shdma: add R-Car Audio DMAC peri peri driver

Add support Audio DMAC peri peri driver
for Renesas R-Car Gen2 SoC, using 'shdma-base'
DMA driver framework.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[fixed checkpatch error]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

(cherry picked from commit e43a34e3ec5d1b14a11c3220f5a12aa797d73cd1)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

3 files changed, 327 insertions, 0 deletions

diff --git a/drivers/dma/sh/Kconfig b/drivers/dma/sh/Kconfig
index dadd9e010c0b..b4c813831006 100644
--- a/drivers/dma/sh/Kconfig
+++ b/drivers/dma/sh/Kconfig
@@ -29,6 +29,12 @@ config RCAR_HPB_DMAE
 	help
 	  Enable support for the Renesas R-Car series DMA controllers.
 
+config RCAR_AUDMAC_PP
+	tristate "Renesas R-Car Audio DMAC Peripheral Peripheral support"
+	depends on SH_DMAE_BASE
+	help
+	  Enable support for the Renesas R-Car Audio DMAC Peripheral Peripheral controllers.
+
 config SHDMA_R8A73A4
 	def_bool y
 	depends on ARCH_R8A73A4 && SH_DMAE != n
diff --git a/drivers/dma/sh/Makefile b/drivers/dma/sh/Makefile
index e856af23b789..1ce88b28cfc6 100644
--- a/drivers/dma/sh/Makefile
+++ b/drivers/dma/sh/Makefile
@@ -7,3 +7,4 @@ endif
 shdma-objs := $(shdma-y)
 obj-$(CONFIG_SUDMAC) += sudmac.o
 obj-$(CONFIG_RCAR_HPB_DMAE) += rcar-hpbdma.o
+obj-$(CONFIG_RCAR_AUDMAC_PP) += rcar-audmapp.o
diff --git a/drivers/dma/sh/rcar-audmapp.c b/drivers/dma/sh/rcar-audmapp.c
new file mode 100644
index 000000000000..2de77289a2e9
--- /dev/null
+++ b/drivers/dma/sh/rcar-audmapp.c
@@ -0,0 +1,320 @@
+/*
+ * This is for Renesas R-Car Audio-DMAC-peri-peri.
+ *
+ * Copyright (C) 2014 Renesas Electronics Corporation
+ * Copyright (C) 2014 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
+ *
+ * based on the drivers/dma/sh/shdma.c
+ *
+ * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
+ * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
+ * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_data/dma-rcar-audmapp.h>
+#include <linux/platform_device.h>
+#include <linux/shdma-base.h>
+
+/*
+ * DMA register
+ */
+#define PDMASAR		0x00
+#define PDMADAR		0x04
+#define PDMACHCR	0x0c
+
+/* PDMACHCR */
+#define PDMACHCR_DE		(1 << 0)
+
+#define AUDMAPP_MAX_CHANNELS	29
+
+/* Default MEMCPY transfer size = 2^2 = 4 bytes */
+#define LOG2_DEFAULT_XFER_SIZE	2
+#define AUDMAPP_SLAVE_NUMBER	256
+#define AUDMAPP_LEN_MAX		(16 * 1024 * 1024)
+
+struct audmapp_chan {
+	struct shdma_chan shdma_chan;
+	struct audmapp_slave_config *config;
+	void __iomem *base;
+};
+
+struct audmapp_device {
+	struct shdma_dev shdma_dev;
+	struct audmapp_pdata *pdata;
+	struct device *dev;
+	void __iomem *chan_reg;
+};
+
+#define to_chan(chan) container_of(chan, struct audmapp_chan, shdma_chan)
+#define to_dev(chan) container_of(chan->shdma_chan.dma_chan.device,	\
+				  struct audmapp_device, shdma_dev.dma_dev)
+
+static void audmapp_write(struct audmapp_chan *auchan, u32 data, u32 reg)
+{
+	struct audmapp_device *audev = to_dev(auchan);
+	struct device *dev = audev->dev;
+
+	dev_dbg(dev, "w %p : %08x\n", auchan->base + reg, data);
+
+	iowrite32(data, auchan->base + reg);
+}
+
+static u32 audmapp_read(struct audmapp_chan *auchan, u32 reg)
+{
+	return ioread32(auchan->base + reg);
+}
+
+static void audmapp_halt(struct shdma_chan *schan)
+{
+	struct audmapp_chan *auchan = to_chan(schan);
+	int i;
+
+	audmapp_write(auchan, 0, PDMACHCR);
+
+	for (i = 0; i < 1024; i++) {
+		if (0 == audmapp_read(auchan, PDMACHCR))
+			return;
+		udelay(1);
+	}
+}
+
+static void audmapp_start_xfer(struct shdma_chan *schan,
+			       struct shdma_desc *sdecs)
+{
+	struct audmapp_chan *auchan = to_chan(schan);
+	struct audmapp_device *audev = to_dev(auchan);
+	struct audmapp_slave_config *cfg = auchan->config;
+	struct device *dev = audev->dev;
+	u32 chcr = cfg->chcr | PDMACHCR_DE;
+
+	dev_dbg(dev, "src/dst/chcr = %pad/%pad/%x\n",
+		&cfg->src, &cfg->dst, cfg->chcr);
+
+	audmapp_write(auchan, cfg->src,	PDMASAR);
+	audmapp_write(auchan, cfg->dst,	PDMADAR);
+	audmapp_write(auchan, chcr,	PDMACHCR);
+}
+
+static struct audmapp_slave_config *
+audmapp_find_slave(struct audmapp_chan *auchan, int slave_id)
+{
+	struct audmapp_device *audev = to_dev(auchan);
+	struct audmapp_pdata *pdata = audev->pdata;
+	struct audmapp_slave_config *cfg;
+	int i;
+
+	if (slave_id >= AUDMAPP_SLAVE_NUMBER)
+		return NULL;
+
+	for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
+		if (cfg->slave_id == slave_id)
+			return cfg;
+
+	return NULL;
+}
+
+static int audmapp_set_slave(struct shdma_chan *schan, int slave_id,
+			     dma_addr_t slave_addr, bool try)
+{
+	struct audmapp_chan *auchan = to_chan(schan);
+	struct audmapp_slave_config *cfg =
+		audmapp_find_slave(auchan, slave_id);
+
+	if (!cfg)
+		return -ENODEV;
+	if (try)
+		return 0;
+
+	auchan->config	= cfg;
+
+	return 0;
+}
+
+static int audmapp_desc_setup(struct shdma_chan *schan,
+			      struct shdma_desc *sdecs,
+			      dma_addr_t src, dma_addr_t dst, size_t *len)
+{
+	struct audmapp_chan *auchan = to_chan(schan);
+	struct audmapp_slave_config *cfg = auchan->config;
+
+	if (!cfg)
+		return -ENODEV;
+
+	if (*len > (size_t)AUDMAPP_LEN_MAX)
+		*len = (size_t)AUDMAPP_LEN_MAX;
+
+	return 0;
+}
+
+static void audmapp_setup_xfer(struct shdma_chan *schan,
+			       int slave_id)
+{
+}
+
+static dma_addr_t audmapp_slave_addr(struct shdma_chan *schan)
+{
+	return 0; /* always fixed address */
+}
+
+static bool audmapp_channel_busy(struct shdma_chan *schan)
+{
+	struct audmapp_chan *auchan = to_chan(schan);
+	u32 chcr = audmapp_read(auchan, PDMACHCR);
+
+	return chcr & ~PDMACHCR_DE;
+}
+
+static bool audmapp_desc_completed(struct shdma_chan *schan,
+				   struct shdma_desc *sdesc)
+{
+	return true;
+}
+
+static struct shdma_desc *audmapp_embedded_desc(void *buf, int i)
+{
+	return &((struct shdma_desc *)buf)[i];
+}
+
+static const struct shdma_ops audmapp_shdma_ops = {
+	.halt_channel	= audmapp_halt,
+	.desc_setup	= audmapp_desc_setup,
+	.set_slave	= audmapp_set_slave,
+	.start_xfer	= audmapp_start_xfer,
+	.embedded_desc	= audmapp_embedded_desc,
+	.setup_xfer	= audmapp_setup_xfer,
+	.slave_addr	= audmapp_slave_addr,
+	.channel_busy	= audmapp_channel_busy,
+	.desc_completed	= audmapp_desc_completed,
+};
+
+static int audmapp_chan_probe(struct platform_device *pdev,
+			      struct audmapp_device *audev, int id)
+{
+	struct shdma_dev *sdev = &audev->shdma_dev;
+	struct audmapp_chan *auchan;
+	struct shdma_chan *schan;
+	struct device *dev = audev->dev;
+
+	auchan = devm_kzalloc(dev, sizeof(*auchan), GFP_KERNEL);
+	if (!auchan)
+		return -ENOMEM;
+
+	schan = &auchan->shdma_chan;
+	schan->max_xfer_len = AUDMAPP_LEN_MAX;
+
+	shdma_chan_probe(sdev, schan, id);
+
+	auchan->base = audev->chan_reg + 0x20 + (0x10 * id);
+	dev_dbg(dev, "%02d : %p / %p", id, auchan->base, audev->chan_reg);
+
+	return 0;
+}
+
+static void audmapp_chan_remove(struct audmapp_device *audev)
+{
+	struct dma_device *dma_dev = &audev->shdma_dev.dma_dev;
+	struct shdma_chan *schan;
+	int i;
+
+	shdma_for_each_chan(schan, &audev->shdma_dev, i) {
+		BUG_ON(!schan);
+		shdma_chan_remove(schan);
+	}
+	dma_dev->chancnt = 0;
+}
+
+static int audmapp_probe(struct platform_device *pdev)
+{
+	struct audmapp_pdata *pdata = pdev->dev.platform_data;
+	struct audmapp_device *audev;
+	struct shdma_dev *sdev;
+	struct dma_device *dma_dev;
+	struct resource *res;
+	int err, i;
+
+	if (!pdata)
+		return -ENODEV;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	audev = devm_kzalloc(&pdev->dev, sizeof(*audev), GFP_KERNEL);
+	if (!audev)
+		return -ENOMEM;
+
+	audev->dev	= &pdev->dev;
+	audev->pdata	= pdata;
+	audev->chan_reg	= devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(audev->chan_reg))
+		return PTR_ERR(audev->chan_reg);
+
+	sdev		= &audev->shdma_dev;
+	sdev->ops	= &audmapp_shdma_ops;
+	sdev->desc_size	= sizeof(struct shdma_desc);
+
+	dma_dev			= &sdev->dma_dev;
+	dma_dev->copy_align	= LOG2_DEFAULT_XFER_SIZE;
+	dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
+
+	err = shdma_init(&pdev->dev, sdev, AUDMAPP_MAX_CHANNELS);
+	if (err < 0)
+		return err;
+
+	platform_set_drvdata(pdev, audev);
+
+	/* Create DMA Channel */
+	for (i = 0; i < AUDMAPP_MAX_CHANNELS; i++) {
+		err = audmapp_chan_probe(pdev, audev, i);
+		if (err)
+			goto chan_probe_err;
+	}
+
+	err = dma_async_device_register(dma_dev);
+	if (err < 0)
+		goto chan_probe_err;
+
+	return err;
+
+chan_probe_err:
+	audmapp_chan_remove(audev);
+	shdma_cleanup(sdev);
+
+	return err;
+}
+
+static int audmapp_remove(struct platform_device *pdev)
+{
+	struct audmapp_device *audev = platform_get_drvdata(pdev);
+	struct dma_device *dma_dev = &audev->shdma_dev.dma_dev;
+
+	dma_async_device_unregister(dma_dev);
+
+	audmapp_chan_remove(audev);
+	shdma_cleanup(&audev->shdma_dev);
+
+	return 0;
+}
+
+static struct platform_driver audmapp_driver = {
+	.probe		= audmapp_probe,
+	.remove		= audmapp_remove,
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= "rcar-audmapp-engine",
+	},
+};
+module_platform_driver(audmapp_driver);
+
+MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
+MODULE_DESCRIPTION("Renesas R-Car Audio DMAC peri-peri driver");
+MODULE_LICENSE("GPL");