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Diffstat (limited to 'arch/arm/plat-samsung/dma-ops.c')
-rw-r--r--arch/arm/plat-samsung/dma-ops.c133
1 files changed, 133 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
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--- /dev/null
+++ b/arch/arm/plat-samsung/dma-ops.c
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+/* 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 <linux/export.h>
+
+#include <mach/dma.h>
+
+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;
+ void *filter_param;
+
+ dma_cap_zero(mask);
+ dma_cap_set(info->cap, mask);
+
+ /*
+ * If a dma channel property of a device node from device tree is
+ * specified, use that as the fliter parameter.
+ */
+ filter_param = (dma_ch == DMACH_DT_PROP) ? (void *)info->dt_dmach_prop :
+ (void *)dma_ch;
+ chan = dma_request_channel(mask, pl330_filter, filter_param);
+
+ if (info->direction == DMA_DEV_TO_MEM) {
+ 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_MEM_TO_DEV) {
+ 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 = dmaengine_prep_slave_sg(chan,
+ &sg, 1, info->direction, DMA_PREP_INTERRUPT);
+ break;
+ case DMA_CYCLIC:
+ desc = dmaengine_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);
+}
+
+static 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);