diff options
| -rw-r--r-- | target/linux/ramips/patches-3.10/0300-DMA-add-rt2880-dma-engine.patch | 670 |
1 files changed, 670 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-3.10/0300-DMA-add-rt2880-dma-engine.patch b/target/linux/ramips/patches-3.10/0300-DMA-add-rt2880-dma-engine.patch new file mode 100644 index 0000000000..8c8ddb9aca --- /dev/null +++ b/target/linux/ramips/patches-3.10/0300-DMA-add-rt2880-dma-engine.patch @@ -0,0 +1,670 @@ +From 776726ff626249276936a7e1f865103ea4e1b7e9 Mon Sep 17 00:00:00 2001 +From: John Crispin <blogic@openwrt.org> +Date: Tue, 3 Dec 2013 17:05:05 +0100 +Subject: [PATCH] DMA: add rt2880 dma engine + +Signed-off-by: John Crispin <blogic@openwrt.org> +--- + drivers/dma/Kconfig | 6 + + drivers/dma/Makefile | 1 + + drivers/dma/ralink-gdma.c | 596 +++++++++++++++++++++++++++++++++++++++++++++ + 3 files changed, 603 insertions(+) + create mode 100644 drivers/dma/ralink-gdma.c + +Index: linux-3.10.18/drivers/dma/Kconfig +=================================================================== +--- linux-3.10.18.orig/drivers/dma/Kconfig 2013-11-04 13:31:29.000000000 +0100 ++++ linux-3.10.18/drivers/dma/Kconfig 2013-12-04 17:52:32.852756567 +0100 +@@ -312,6 +312,12 @@ + help + Support the MMP PDMA engine for PXA and MMP platfrom. + ++config DMA_RALINK ++ tristate "RALINK DMA support" ++ depends on RALINK && SOC_MT7620 ++ select DMA_ENGINE ++ select DMA_VIRTUAL_CHANNELS ++ + config DMA_ENGINE + bool + +Index: linux-3.10.18/drivers/dma/ralink-gdma.c +=================================================================== +--- /dev/null 1970-01-01 00:00:00.000000000 +0000 ++++ linux-3.10.18/drivers/dma/ralink-gdma.c 2013-12-05 21:17:22.245128605 +0100 +@@ -0,0 +1,577 @@ ++/* ++ * Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de> ++ * GDMA4740 DMAC support ++ * ++ * This program 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. ++ * ++ * You should have received a copy of the GNU General Public License along ++ * with this program; if not, write to the Free Software Foundation, Inc., ++ * 675 Mass Ave, Cambridge, MA 02139, USA. ++ * ++ */ ++ ++#include <linux/dmaengine.h> ++#include <linux/dma-mapping.h> ++#include <linux/err.h> ++#include <linux/init.h> ++#include <linux/list.h> ++#include <linux/module.h> ++#include <linux/platform_device.h> ++#include <linux/slab.h> ++#include <linux/spinlock.h> ++#include <linux/irq.h> ++#include <linux/of_dma.h> ++ ++#include "virt-dma.h" ++ ++#define GDMA_NR_CHANS 16 ++ ++#define GDMA_REG_SRC_ADDR(x) (0x00 + (x) * 0x10) ++#define GDMA_REG_DST_ADDR(x) (0x04 + (x) * 0x10) ++ ++#define GDMA_REG_CTRL0(x) (0x08 + (x) * 0x10) ++#define GDMA_REG_CTRL0_TX_MASK 0xffff ++#define GDMA_REG_CTRL0_TX_SHIFT 16 ++#define GDMA_REG_CTRL0_CURR_MASK 0xff ++#define GDMA_REG_CTRL0_CURR_SHIFT 8 ++#define GDMA_REG_CTRL0_SRC_ADDR_FIXED BIT(7) ++#define GDMA_REG_CTRL0_DST_ADDR_FIXED BIT(6) ++#define GDMA_REG_CTRL0_BURST_MASK 0x7 ++#define GDMA_REG_CTRL0_BURST_SHIFT 3 ++#define GDMA_REG_CTRL0_DONE_INT BIT(2) ++#define GDMA_REG_CTRL0_ENABLE BIT(1) ++#define GDMA_REG_CTRL0_HW_MODE 0 ++ ++#define GDMA_REG_CTRL1(x) (0x0c + (x) * 0x10) ++#define GDMA_REG_CTRL1_SEG_MASK 0xf ++#define GDMA_REG_CTRL1_SEG_SHIFT 22 ++#define GDMA_REG_CTRL1_REQ_MASK 0x3f ++#define GDMA_REG_CTRL1_SRC_REQ_SHIFT 16 ++#define GDMA_REG_CTRL1_DST_REQ_SHIFT 8 ++#define GDMA_REG_CTRL1_CONTINOUS BIT(14) ++#define GDMA_REG_CTRL1_NEXT_MASK 0x1f ++#define GDMA_REG_CTRL1_NEXT_SHIFT 3 ++#define GDMA_REG_CTRL1_COHERENT BIT(2) ++#define GDMA_REG_CTRL1_FAIL BIT(1) ++#define GDMA_REG_CTRL1_MASK BIT(0) ++ ++#define GDMA_REG_UNMASK_INT 0x200 ++#define GDMA_REG_DONE_INT 0x204 ++ ++#define GDMA_REG_GCT 0x220 ++#define GDMA_REG_GCT_CHAN_MASK 0x3 ++#define GDMA_REG_GCT_CHAN_SHIFT 3 ++#define GDMA_REG_GCT_VER_MASK 0x3 ++#define GDMA_REG_GCT_VER_SHIFT 1 ++#define GDMA_REG_GCT_ARBIT_RR BIT(0) ++ ++enum gdma_dma_transfer_size { ++ GDMA_TRANSFER_SIZE_4BYTE = 0, ++ GDMA_TRANSFER_SIZE_8BYTE = 1, ++ GDMA_TRANSFER_SIZE_16BYTE = 2, ++ GDMA_TRANSFER_SIZE_32BYTE = 3, ++}; ++ ++struct gdma_dma_sg { ++ dma_addr_t addr; ++ unsigned int len; ++}; ++ ++struct gdma_dma_desc { ++ struct virt_dma_desc vdesc; ++ ++ enum dma_transfer_direction direction; ++ bool cyclic; ++ ++ unsigned int num_sgs; ++ struct gdma_dma_sg sg[]; ++}; ++ ++struct gdma_dmaengine_chan { ++ struct virt_dma_chan vchan; ++ unsigned int id; ++ ++ dma_addr_t fifo_addr; ++ unsigned int transfer_shift; ++ ++ struct gdma_dma_desc *desc; ++ unsigned int next_sg; ++}; ++ ++struct gdma_dma_dev { ++ struct dma_device ddev; ++ void __iomem *base; ++ struct clk *clk; ++ ++ struct gdma_dmaengine_chan chan[GDMA_NR_CHANS]; ++}; ++ ++static struct gdma_dma_dev *gdma_dma_chan_get_dev( ++ struct gdma_dmaengine_chan *chan) ++{ ++ return container_of(chan->vchan.chan.device, struct gdma_dma_dev, ++ ddev); ++} ++ ++static struct gdma_dmaengine_chan *to_gdma_dma_chan(struct dma_chan *c) ++{ ++ return container_of(c, struct gdma_dmaengine_chan, vchan.chan); ++} ++ ++static struct gdma_dma_desc *to_gdma_dma_desc(struct virt_dma_desc *vdesc) ++{ ++ return container_of(vdesc, struct gdma_dma_desc, vdesc); ++} ++ ++static inline uint32_t gdma_dma_read(struct gdma_dma_dev *dma_dev, ++ unsigned int reg) ++{ ++ return readl(dma_dev->base + reg); ++} ++ ++static inline void gdma_dma_write(struct gdma_dma_dev *dma_dev, ++ unsigned reg, uint32_t val) ++{ ++ //printk("gdma --> %p = 0x%08X\n", dma_dev->base + reg, val); ++ writel(val, dma_dev->base + reg); ++} ++ ++static inline void gdma_dma_write_mask(struct gdma_dma_dev *dma_dev, ++ unsigned int reg, uint32_t val, uint32_t mask) ++{ ++ uint32_t tmp; ++ ++ tmp = gdma_dma_read(dma_dev, reg); ++ tmp &= ~mask; ++ tmp |= val; ++ gdma_dma_write(dma_dev, reg, tmp); ++} ++ ++static struct gdma_dma_desc *gdma_dma_alloc_desc(unsigned int num_sgs) ++{ ++ return kzalloc(sizeof(struct gdma_dma_desc) + ++ sizeof(struct gdma_dma_sg) * num_sgs, GFP_ATOMIC); ++} ++ ++static enum gdma_dma_transfer_size gdma_dma_maxburst(u32 maxburst) ++{ ++ if (maxburst <= 7) ++ return GDMA_TRANSFER_SIZE_4BYTE; ++ else if (maxburst <= 15) ++ return GDMA_TRANSFER_SIZE_8BYTE; ++ else if (maxburst <= 31) ++ return GDMA_TRANSFER_SIZE_16BYTE; ++ ++ return GDMA_TRANSFER_SIZE_32BYTE; ++} ++ ++static int gdma_dma_slave_config(struct dma_chan *c, ++ const struct dma_slave_config *config) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan); ++ enum gdma_dma_transfer_size transfer_size; ++ uint32_t flags; ++ uint32_t ctrl0, ctrl1; ++ ++ switch (config->direction) { ++ case DMA_MEM_TO_DEV: ++ ctrl1 = 32 << GDMA_REG_CTRL1_SRC_REQ_SHIFT; ++ ctrl1 |= config->slave_id << GDMA_REG_CTRL1_DST_REQ_SHIFT; ++ flags = GDMA_REG_CTRL0_DST_ADDR_FIXED; ++ transfer_size = gdma_dma_maxburst(config->dst_maxburst); ++ chan->fifo_addr = config->dst_addr; ++ break; ++ ++ case DMA_DEV_TO_MEM: ++ ctrl1 = config->slave_id << GDMA_REG_CTRL1_SRC_REQ_SHIFT; ++ ctrl1 |= 32 << GDMA_REG_CTRL1_DST_REQ_SHIFT; ++ flags = GDMA_REG_CTRL0_SRC_ADDR_FIXED; ++ transfer_size = gdma_dma_maxburst(config->src_maxburst); ++ chan->fifo_addr = config->src_addr; ++ break; ++ ++ default: ++ return -EINVAL; ++ } ++ ++ chan->transfer_shift = 1 + transfer_size; ++ ++ ctrl0 = flags | GDMA_REG_CTRL0_HW_MODE; ++ ctrl0 |= GDMA_REG_CTRL0_DONE_INT; ++ ++ ctrl1 &= ~(GDMA_REG_CTRL1_NEXT_MASK << GDMA_REG_CTRL1_NEXT_SHIFT); ++ ctrl1 |= chan->id << GDMA_REG_CTRL1_NEXT_SHIFT; ++ ctrl1 |= GDMA_REG_CTRL1_FAIL; ++ ctrl1 &= ~GDMA_REG_CTRL1_CONTINOUS; ++ gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), ctrl0); ++ gdma_dma_write(dma_dev, GDMA_REG_CTRL1(chan->id), ctrl1); ++ ++ return 0; ++} ++ ++static int gdma_dma_terminate_all(struct dma_chan *c) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan); ++ unsigned long flags; ++ LIST_HEAD(head); ++ ++ spin_lock_irqsave(&chan->vchan.lock, flags); ++ gdma_dma_write_mask(dma_dev, GDMA_REG_CTRL0(chan->id), 0, ++ GDMA_REG_CTRL0_ENABLE); ++ chan->desc = NULL; ++ vchan_get_all_descriptors(&chan->vchan, &head); ++ spin_unlock_irqrestore(&chan->vchan.lock, flags); ++ ++ vchan_dma_desc_free_list(&chan->vchan, &head); ++ ++ return 0; ++} ++ ++static int gdma_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, ++ unsigned long arg) ++{ ++ struct dma_slave_config *config = (struct dma_slave_config *)arg; ++ ++ switch (cmd) { ++ case DMA_SLAVE_CONFIG: ++ return gdma_dma_slave_config(chan, config); ++ case DMA_TERMINATE_ALL: ++ return gdma_dma_terminate_all(chan); ++ default: ++ return -ENOSYS; ++ } ++} ++ ++static int gdma_dma_start_transfer(struct gdma_dmaengine_chan *chan) ++{ ++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan); ++ dma_addr_t src_addr, dst_addr; ++ struct virt_dma_desc *vdesc; ++ struct gdma_dma_sg *sg; ++ ++ gdma_dma_write_mask(dma_dev, GDMA_REG_CTRL0(chan->id), 0, ++ GDMA_REG_CTRL0_ENABLE); ++ ++ if (!chan->desc) { ++ vdesc = vchan_next_desc(&chan->vchan); ++ if (!vdesc) ++ return 0; ++ chan->desc = to_gdma_dma_desc(vdesc); ++ chan->next_sg = 0; ++ } ++ ++ if (chan->next_sg == chan->desc->num_sgs) ++ chan->next_sg = 0; ++ ++ sg = &chan->desc->sg[chan->next_sg]; ++ ++ if (chan->desc->direction == DMA_MEM_TO_DEV) { ++ src_addr = sg->addr; ++ dst_addr = chan->fifo_addr; ++ } else { ++ src_addr = chan->fifo_addr; ++ dst_addr = sg->addr; ++ } ++ gdma_dma_write(dma_dev, GDMA_REG_SRC_ADDR(chan->id), src_addr); ++ gdma_dma_write(dma_dev, GDMA_REG_DST_ADDR(chan->id), dst_addr); ++ gdma_dma_write_mask(dma_dev, GDMA_REG_CTRL0(chan->id), ++ (sg->len << GDMA_REG_CTRL0_TX_SHIFT) | GDMA_REG_CTRL0_ENABLE, ++ GDMA_REG_CTRL0_TX_MASK << GDMA_REG_CTRL0_TX_SHIFT); ++ chan->next_sg++; ++ gdma_dma_write_mask(dma_dev, GDMA_REG_CTRL1(chan->id), 0, GDMA_REG_CTRL1_MASK); ++ ++ return 0; ++} ++ ++static void gdma_dma_chan_irq(struct gdma_dmaengine_chan *chan) ++{ ++ spin_lock(&chan->vchan.lock); ++ if (chan->desc) { ++ if (chan->desc && chan->desc->cyclic) { ++ vchan_cyclic_callback(&chan->desc->vdesc); ++ } else { ++ if (chan->next_sg == chan->desc->num_sgs) { ++ chan->desc = NULL; ++ vchan_cookie_complete(&chan->desc->vdesc); ++ } ++ } ++ } ++ gdma_dma_start_transfer(chan); ++ spin_unlock(&chan->vchan.lock); ++} ++ ++static irqreturn_t gdma_dma_irq(int irq, void *devid) ++{ ++ struct gdma_dma_dev *dma_dev = devid; ++ uint32_t unmask, done; ++ unsigned int i; ++ ++ unmask = gdma_dma_read(dma_dev, GDMA_REG_UNMASK_INT); ++ gdma_dma_write(dma_dev, GDMA_REG_UNMASK_INT, unmask); ++ done = gdma_dma_read(dma_dev, GDMA_REG_DONE_INT); ++ ++ for (i = 0; i < GDMA_NR_CHANS; ++i) ++ if (done & BIT(i)) ++ gdma_dma_chan_irq(&dma_dev->chan[i]); ++ gdma_dma_write(dma_dev, GDMA_REG_DONE_INT, done); ++ ++ return IRQ_HANDLED; ++} ++ ++static void gdma_dma_issue_pending(struct dma_chan *c) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ unsigned long flags; ++ ++ spin_lock_irqsave(&chan->vchan.lock, flags); ++ if (vchan_issue_pending(&chan->vchan) && !chan->desc) ++ gdma_dma_start_transfer(chan); ++ spin_unlock_irqrestore(&chan->vchan.lock, flags); ++} ++ ++static struct dma_async_tx_descriptor *gdma_dma_prep_slave_sg( ++ struct dma_chan *c, struct scatterlist *sgl, ++ unsigned int sg_len, enum dma_transfer_direction direction, ++ unsigned long flags, void *context) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ struct gdma_dma_desc *desc; ++ struct scatterlist *sg; ++ unsigned int i; ++ ++ desc = gdma_dma_alloc_desc(sg_len); ++ if (!desc) ++ return NULL; ++ ++ for_each_sg(sgl, sg, sg_len, i) { ++ desc->sg[i].addr = sg_dma_address(sg); ++ desc->sg[i].len = sg_dma_len(sg); ++ } ++ ++ desc->num_sgs = sg_len; ++ desc->direction = direction; ++ desc->cyclic = false; ++ ++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); ++} ++ ++static struct dma_async_tx_descriptor *gdma_dma_prep_dma_cyclic( ++ struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len, ++ size_t period_len, enum dma_transfer_direction direction, ++ unsigned long flags, void *context) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ struct gdma_dma_desc *desc; ++ unsigned int num_periods, i; ++ ++ if (buf_len % period_len) ++ return NULL; ++ ++ num_periods = buf_len / period_len; ++ ++ desc = gdma_dma_alloc_desc(num_periods); ++ if (!desc) ++ return NULL; ++ ++ for (i = 0; i < num_periods; i++) { ++ desc->sg[i].addr = buf_addr; ++ desc->sg[i].len = period_len; ++ buf_addr += period_len; ++ } ++ ++ desc->num_sgs = num_periods; ++ desc->direction = direction; ++ desc->cyclic = true; ++ ++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); ++} ++ ++static size_t gdma_dma_desc_residue(struct gdma_dmaengine_chan *chan, ++ struct gdma_dma_desc *desc, unsigned int next_sg) ++{ ++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan); ++ unsigned int residue, count; ++ unsigned int i; ++ ++ residue = 0; ++ ++ for (i = next_sg; i < desc->num_sgs; i++) ++ residue += desc->sg[i].len; ++ ++ if (next_sg != 0) { ++ count = gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id)); ++ count >>= GDMA_REG_CTRL0_CURR_SHIFT; ++ count &= GDMA_REG_CTRL0_CURR_MASK; ++ residue += count << chan->transfer_shift; ++ } ++ ++ return residue; ++} ++ ++static enum dma_status gdma_dma_tx_status(struct dma_chan *c, ++ dma_cookie_t cookie, struct dma_tx_state *state) ++{ ++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c); ++ struct virt_dma_desc *vdesc; ++ enum dma_status status; ++ unsigned long flags; ++ ++ status = dma_cookie_status(c, cookie, state); ++ if (status == DMA_SUCCESS || !state) ++ return status; ++ ++ spin_lock_irqsave(&chan->vchan.lock, flags); ++ vdesc = vchan_find_desc(&chan->vchan, cookie); ++ if (cookie == chan->desc->vdesc.tx.cookie) { ++ state->residue = gdma_dma_desc_residue(chan, chan->desc, ++ chan->next_sg); ++ } else if (vdesc) { ++ state->residue = gdma_dma_desc_residue(chan, ++ to_gdma_dma_desc(vdesc), 0); ++ } else { ++ state->residue = 0; ++ } ++ spin_unlock_irqrestore(&chan->vchan.lock, flags); ++ ++ return status; ++} ++ ++static int gdma_dma_alloc_chan_resources(struct dma_chan *c) ++{ ++ return 0; ++} ++ ++static void gdma_dma_free_chan_resources(struct dma_chan *c) ++{ ++ vchan_free_chan_resources(to_virt_chan(c)); ++} ++ ++static void gdma_dma_desc_free(struct virt_dma_desc *vdesc) ++{ ++ kfree(container_of(vdesc, struct gdma_dma_desc, vdesc)); ++} ++ ++static struct dma_chan * ++of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec, ++ struct of_dma *ofdma) ++{ ++ struct gdma_dma_dev *dma_dev = ofdma->of_dma_data; ++ unsigned int request = dma_spec->args[0]; ++ ++ if (request >= GDMA_NR_CHANS) ++ return NULL; ++ ++ return dma_get_slave_channel(&(dma_dev->chan[request].vchan.chan)); ++} ++ ++static int gdma_dma_probe(struct platform_device *pdev) ++{ ++ struct gdma_dmaengine_chan *chan; ++ struct gdma_dma_dev *dma_dev; ++ struct dma_device *dd; ++ unsigned int i; ++ struct resource *res; ++ uint32_t gct; ++ int ret; ++ int irq; ++ ++ ++ dma_dev = devm_kzalloc(&pdev->dev, sizeof(*dma_dev), GFP_KERNEL); ++ if (!dma_dev) ++ return -EINVAL; ++ ++ dd = &dma_dev->ddev; ++ ++ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); ++ dma_dev->base = devm_ioremap_resource(&pdev->dev, res); ++ if (IS_ERR(dma_dev->base)) ++ return PTR_ERR(dma_dev->base); ++ ++ dma_cap_set(DMA_SLAVE, dd->cap_mask); ++ dma_cap_set(DMA_CYCLIC, dd->cap_mask); ++ dd->device_alloc_chan_resources = gdma_dma_alloc_chan_resources; ++ dd->device_free_chan_resources = gdma_dma_free_chan_resources; ++ dd->device_tx_status = gdma_dma_tx_status; ++ dd->device_issue_pending = gdma_dma_issue_pending; ++ dd->device_prep_slave_sg = gdma_dma_prep_slave_sg; ++ dd->device_prep_dma_cyclic = gdma_dma_prep_dma_cyclic; ++ dd->device_control = gdma_dma_control; ++ dd->dev = &pdev->dev; ++ dd->chancnt = GDMA_NR_CHANS; ++ INIT_LIST_HEAD(&dd->channels); ++ ++ for (i = 0; i < dd->chancnt; i++) { ++ chan = &dma_dev->chan[i]; ++ chan->id = i; ++ chan->vchan.desc_free = gdma_dma_desc_free; ++ vchan_init(&chan->vchan, dd); ++ } ++ ++ ret = dma_async_device_register(dd); ++ if (ret) ++ return ret; ++ ++ ret = of_dma_controller_register(pdev->dev.of_node, ++ of_dma_xlate_by_chan_id, dma_dev); ++ if (ret) ++ goto err_unregister; ++ ++ irq = platform_get_irq(pdev, 0); ++ ret = request_irq(irq, gdma_dma_irq, 0, dev_name(&pdev->dev), dma_dev); ++ if (ret) ++ goto err_unregister; ++ ++ gdma_dma_write(dma_dev, GDMA_REG_UNMASK_INT, 0); ++ gdma_dma_write(dma_dev, GDMA_REG_DONE_INT, BIT(dd->chancnt) - 1); ++ ++ gct = gdma_dma_read(dma_dev, GDMA_REG_GCT); ++ dev_info(&pdev->dev, "revision: %d, channels: %d\n", ++ (gct >> GDMA_REG_GCT_VER_SHIFT) & GDMA_REG_GCT_VER_MASK, ++ 8 << ((gct >> GDMA_REG_GCT_CHAN_SHIFT) & GDMA_REG_GCT_CHAN_MASK)); ++ platform_set_drvdata(pdev, dma_dev); ++ ++ gdma_dma_write(dma_dev, GDMA_REG_GCT, GDMA_REG_GCT_ARBIT_RR); ++ ++ return 0; ++ ++err_unregister: ++ dma_async_device_unregister(dd); ++ return ret; ++} ++ ++static int gdma_dma_remove(struct platform_device *pdev) ++{ ++ struct gdma_dma_dev *dma_dev = platform_get_drvdata(pdev); ++ int irq = platform_get_irq(pdev, 0); ++ ++ free_irq(irq, dma_dev); ++ of_dma_controller_free(pdev->dev.of_node); ++ dma_async_device_unregister(&dma_dev->ddev); ++ ++ return 0; ++} ++ ++static const struct of_device_id gdma_of_match_table[] = { ++ { .compatible = "ralink,rt2880-gdma" }, ++ { }, ++}; ++ ++static struct platform_driver gdma_dma_driver = { ++ .probe = gdma_dma_probe, ++ .remove = gdma_dma_remove, ++ .driver = { ++ .name = "gdma-rt2880", ++ .owner = THIS_MODULE, ++ .of_match_table = gdma_of_match_table, ++ }, ++}; ++module_platform_driver(gdma_dma_driver); ++ ++MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); ++MODULE_DESCRIPTION("GDMA4740 DMA driver"); ++MODULE_LICENSE("GPLv2"); +Index: linux-3.10.18/drivers/dma/dmaengine.c +=================================================================== +--- linux-3.10.18.orig/drivers/dma/dmaengine.c 2013-11-04 13:31:29.000000000 +0100 ++++ linux-3.10.18/drivers/dma/dmaengine.c 2013-12-04 17:52:32.856756568 +0100 +@@ -504,6 +504,32 @@ + } + + /** ++ * dma_request_slave_channel - try to get specific channel exclusively ++ * @chan: target channel ++ */ ++struct dma_chan *dma_get_slave_channel(struct dma_chan *chan) ++{ ++ int err = -EBUSY; ++ ++ /* lock against __dma_request_channel */ ++ mutex_lock(&dma_list_mutex); ++ ++ if (chan->client_count == 0) { ++ err = dma_chan_get(chan); ++ if (err) ++ pr_debug("%s: failed to get %s: (%d)\n", ++ __func__, dma_chan_name(chan), err); ++ } else ++ chan = NULL; ++ ++ mutex_unlock(&dma_list_mutex); ++ ++ return chan; ++} ++EXPORT_SYMBOL_GPL(dma_get_slave_channel); ++ ++ ++/** + * dma_request_channel - try to allocate an exclusive channel + * @mask: capabilities that the channel must satisfy + * @fn: optional callback to disposition available channels +Index: linux-3.10.18/include/linux/dmaengine.h +=================================================================== +--- linux-3.10.18.orig/include/linux/dmaengine.h 2013-11-04 13:31:29.000000000 +0100 ++++ linux-3.10.18/include/linux/dmaengine.h 2013-12-04 17:52:32.856756568 +0100 +@@ -999,6 +999,7 @@ + int dma_async_device_register(struct dma_device *device); + void dma_async_device_unregister(struct dma_device *device); + void dma_run_dependencies(struct dma_async_tx_descriptor *tx); ++struct dma_chan *dma_get_slave_channel(struct dma_chan *chan); + struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type); + struct dma_chan *net_dma_find_channel(void); + #define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y) +Index: linux-3.10.18/drivers/dma/Makefile +=================================================================== +--- linux-3.10.18.orig/drivers/dma/Makefile 2013-11-04 13:31:29.000000000 +0100 ++++ linux-3.10.18/drivers/dma/Makefile 2013-12-04 17:52:32.856756568 +0100 +@@ -38,3 +38,4 @@ + obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o + obj-$(CONFIG_DMA_OMAP) += omap-dma.o + obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o ++obj-$(CONFIG_DMA_RALINK) += ralink-gdma.o |