ARM: SAMSUNG: Add common DMA operations

This patch adds common DMA operations which are used for Samsung DMA
drivers. Currently there are two types of DMA driver for Samsung SoCs.
The one is S3C-DMA for S3C SoCs and the other is PL330-DMA for S5P SoCs.
This patch provides funcion pointers for common DMA operations to DMA
client driver like SPI and Audio. It makes DMA client drivers support
multi-platform.
In addition, this common DMA operations implement the shared actions
that are needed for DMA client driver. For example shared actions are
filter() function for dma_request_channel() and parameter passing for
device_prep_slave_sg().

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 131 insertions, 0 deletions

diff --git a/arch/arm/plat-samsung/dma-ops.c b/arch/arm/plat-samsung/dma-ops.c
new file mode 100644
index 0000000..6e3d9ab
--- /dev/null
+++ b/arch/arm/plat-samsung/dma-ops.c
@@ -0,0 +1,131 @@
+/* linux/arch/arm/plat-samsung/dma-ops.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Samsung DMA Operations
+ *
+ * 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/kernel.h>
+#include <linux/errno.h>
+#include <linux/amba/pl330.h>
+#include <linux/scatterlist.h>
+
+#include <mach/dma.h>
+
+static inline bool pl330_filter(struct dma_chan *chan, void *param)
+{
+	struct dma_pl330_peri *peri = chan->private;
+	return peri->peri_id == (unsigned)param;
+}
+
+static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
+				struct samsung_dma_info *info)
+{
+	struct dma_chan *chan;
+	dma_cap_mask_t mask;
+	struct dma_slave_config slave_config;
+
+	dma_cap_zero(mask);
+	dma_cap_set(info->cap, mask);
+
+	chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch);
+
+	if (info->direction == DMA_FROM_DEVICE) {
+		memset(&slave_config, 0, sizeof(struct dma_slave_config));
+		slave_config.direction = info->direction;
+		slave_config.src_addr = info->fifo;
+		slave_config.src_addr_width = info->width;
+		slave_config.src_maxburst = 1;
+		dmaengine_slave_config(chan, &slave_config);
+	} else if (info->direction == DMA_TO_DEVICE) {
+		memset(&slave_config, 0, sizeof(struct dma_slave_config));
+		slave_config.direction = info->direction;
+		slave_config.dst_addr = info->fifo;
+		slave_config.dst_addr_width = info->width;
+		slave_config.dst_maxburst = 1;
+		dmaengine_slave_config(chan, &slave_config);
+	}
+
+	return (unsigned)chan;
+}
+
+static int samsung_dmadev_release(unsigned ch,
+			struct s3c2410_dma_client *client)
+{
+	dma_release_channel((struct dma_chan *)ch);
+
+	return 0;
+}
+
+static int samsung_dmadev_prepare(unsigned ch,
+			struct samsung_dma_prep_info *info)
+{
+	struct scatterlist sg;
+	struct dma_chan *chan = (struct dma_chan *)ch;
+	struct dma_async_tx_descriptor *desc;
+
+	switch (info->cap) {
+	case DMA_SLAVE:
+		sg_init_table(&sg, 1);
+		sg_dma_len(&sg) = info->len;
+		sg_set_page(&sg, pfn_to_page(PFN_DOWN(info->buf)),
+			    info->len, offset_in_page(info->buf));
+		sg_dma_address(&sg) = info->buf;
+
+		desc = chan->device->device_prep_slave_sg(chan,
+			&sg, 1, info->direction, DMA_PREP_INTERRUPT);
+		break;
+	case DMA_CYCLIC:
+		desc = chan->device->device_prep_dma_cyclic(chan,
+			info->buf, info->len, info->period, info->direction);
+		break;
+	default:
+		dev_err(&chan->dev->device, "unsupported format\n");
+		return -EFAULT;
+	}
+
+	if (!desc) {
+		dev_err(&chan->dev->device, "cannot prepare cyclic dma\n");
+		return -EFAULT;
+	}
+
+	desc->callback = info->fp;
+	desc->callback_param = info->fp_param;
+
+	dmaengine_submit((struct dma_async_tx_descriptor *)desc);
+
+	return 0;
+}
+
+static inline int samsung_dmadev_trigger(unsigned ch)
+{
+	dma_async_issue_pending((struct dma_chan *)ch);
+
+	return 0;
+}
+
+static inline int samsung_dmadev_flush(unsigned ch)
+{
+	return dmaengine_terminate_all((struct dma_chan *)ch);
+}
+
+struct samsung_dma_ops dmadev_ops = {
+	.request	= samsung_dmadev_request,
+	.release	= samsung_dmadev_release,
+	.prepare	= samsung_dmadev_prepare,
+	.trigger	= samsung_dmadev_trigger,
+	.started	= NULL,
+	.flush		= samsung_dmadev_flush,
+	.stop		= samsung_dmadev_flush,
+};
+
+void *samsung_dmadev_get_ops(void)
+{
+	return &dmadev_ops;
+}
+EXPORT_SYMBOL(samsung_dmadev_get_ops);