RE: [PATCHv11 2/2] dma: Add Freescale eDMA engine driver support

From: Jingchang Lu
Date: Mon Jan 27 2014 - 00:20:20 EST

Hi, Vinod,

Let me give some more explanation on the eDMA engine pause and termination here:
The eDMA engine is a request-driven controller, it manage all channels in one engine
and schedule them to perform each one's transfer when one's dma request arrive.
When a dma request of a specific channel is received, the channel's appropriate TCD
Parameter contents are loaded into the eDMA engine, and the appropriate reads and writes
Perform until the minor byte transfer count has transferred, the number of bytes to transfer
per request is determined by the salve's characteristics, such as the FIFO size,
and the dma request condition is also determined by specific slave, such as FIFO empty.
And to the transfer a bunch of data need many dma requests.
So if the dma request enable bit of a channel is cleared, there will be no further dma
Request received by the eDMA engine, thus the channel will never be scheduled to run by
the eDMA engine, the channel is paused, halted, also as stopped. If the channel need to
transfer the remained data with the previous setting, just set the dma request enable bit,
the transfer will complete with slave's dma request.(resume)
If the parameters need be changed, corresponding register parameters can be reprogrammed,
after all is ok, the dma request enable bit can be set to enable a new dma transfer.(terminate)
So is this ok and could it be merged, thanks!


Best Regards,
Jingchang


> -----Original Message-----
> From: Jingchang Lu [mailto:b35083@xxxxxxxxxxxxx]
> Sent: Monday, January 20, 2014 5:24 PM
> To: vinod.koul@xxxxxxxxx
> Cc: dan.j.williams@xxxxxxxxx; arnd@xxxxxxxx; shawn.guo@xxxxxxxxxx;
> pawel.moll@xxxxxxx; mark.rutland@xxxxxxx; swarren@xxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; Lu Jingchang-B35083; Wang Huan-B18965
> Subject: [PATCHv11 2/2] dma: Add Freescale eDMA engine driver support
>
> Add Freescale enhanced direct memory(eDMA) controller support.
> This module can be found on Vybrid and LS-1 SoCs.
>
> Signed-off-by: Alison Wang <b18965@xxxxxxxxxxxxx>
> Signed-off-by: Jingchang Lu <b35083@xxxxxxxxxxxxx>
> Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> changes in v11:
> Add dma device_slave_caps definition.
>
> changes in v10:
> define fsl_edma_mutex in fsl_edma_engine instead of global.
> minor changes of binding description.
>
> changes in v9:
> define endian's operating functions instead of macro definition.
> remove the filter function, using dma_get_slave_channel instead.
>
> changes in v8:
> change the edma driver according eDMA dts change.
> add big-endian and little-endian handling.
>
> no changes in v4 ~ v7.
>
> changes in v3:
> add vf610 edma dt-bindings namespace with prefix VF610_*.
>
> changes in v2:
> using generic dma-channels property instead of fsl,dma-channels.
>
> Documentation/devicetree/bindings/dma/fsl-edma.txt | 76 ++
> drivers/dma/Kconfig | 10 +
> drivers/dma/Makefile | 1 +
> drivers/dma/fsl-edma.c | 975
> +++++++++++++++++++++
> 4 files changed, 1062 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/dma/fsl-edma.txt
> create mode 100644 drivers/dma/fsl-edma.c
>
> diff --git a/Documentation/devicetree/bindings/dma/fsl-edma.txt
> b/Documentation/devicetree/bindings/dma/fsl-edma.txt
> new file mode 100644
> index 0000000..191d7bd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/fsl-edma.txt
> @@ -0,0 +1,76 @@
> +* Freescale enhanced Direct Memory Access(eDMA) Controller
> +
> + The eDMA channels have multiplex capability by programmble memory-
> mapped
> +registers. channels are split into two groups, called DMAMUX0 and
> DMAMUX1,
> +specific DMA request source can only be multiplexed by any channel of
> certain
> +group, DMAMUX0 or DMAMUX1, but not both.
> +
> +* eDMA Controller
> +Required properties:
> +- compatible :
> + - "fsl,vf610-edma" for eDMA used similar to that on Vybrid vf610
> SoC
> +- reg : Specifies base physical address(s) and size of the eDMA
> registers.
> + The 1st region is eDMA control register's address and size.
> + The 2nd and the 3rd regions are programmable channel multiplexing
> + control register's address and size.
> +- interrupts : A list of interrupt-specifiers, one for each entry in
> + interrupt-names.
> +- interrupt-names : Should contain:
> + "edma-tx" - the transmission interrupt
> + "edma-err" - the error interrupt
> +- #dma-cells : Must be <2>.
> + The 1st cell specifies the DMAMUX(0 for DMAMUX0 and 1 for DMAMUX1).
> + Specific request source can only be multiplexed by specific
> channels
> + group called DMAMUX.
> + The 2nd cell specifies the request source(slot) ID.
> + See the SoC's reference manual for all the supported request
> sources.
> +- dma-channels : Number of channels supported by the controller
> +- clock-names : A list of channel group clock names. Should contain:
> + "dmamux0" - clock name of mux0 group
> + "dmamux1" - clock name of mux1 group
> +- clocks : A list of phandle and clock-specifier pairs, one for each
> entry in
> + clock-names.
> +
> +Optional properties:
> +- big-endian: If present registers and hardware scatter/gather
> descriptors
> + of the eDMA are implemented in big endian mode, otherwise in little
> + mode.
> +
> +
> +Examples:
> +
> +edma0: dma-controller@40018000 {
> + #dma-cells = <2>;
> + compatible = "fsl,vf610-edma";
> + reg = <0x40018000 0x2000>,
> + <0x40024000 0x1000>,
> + <0x40025000 0x1000>;
> + interrupts = <0 8 IRQ_TYPE_LEVEL_HIGH>,
> + <0 9 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-names = "edma-tx", "edma-err";
> + dma-channels = <32>;
> + clock-names = "dmamux0", "dmamux1";
> + clocks = <&clks VF610_CLK_DMAMUX0>,
> + <&clks VF610_CLK_DMAMUX1>;
> +};
> +
> +
> +* DMA clients
> +DMA client drivers that uses the DMA function must use the format
> described
> +in the dma.txt file, using a two-cell specifier for each channel: the
> 1st
> +specifies the channel group(DMAMUX) in which this request can be
> multiplexed,
> +and the 2nd specifies the request source.
> +
> +Examples:
> +
> +sai2: sai@40031000 {
> + compatible = "fsl,vf610-sai";
> + reg = <0x40031000 0x1000>;
> + interrupts = <0 86 IRQ_TYPE_LEVEL_HIGH>;
> + clock-names = "sai";
> + clocks = <&clks VF610_CLK_SAI2>;
> + dma-names = "tx", "rx";
> + dmas = <&edma0 0 21>,
> + <&edma0 0 20>;
> + status = "disabled";
> +};
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index 9ae6f54..3d8a522 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -342,6 +342,16 @@ config K3_DMA
> Support the DMA engine for Hisilicon K3 platform
> devices.
>
> +config FSL_EDMA
> + tristate "Freescale eDMA engine support"
> + depends on OF
> + select DMA_ENGINE
> + select DMA_VIRTUAL_CHANNELS
> + help
> + Support the Freescale eDMA engine with programmable channel
> + multiplexing capability for DMA request sources(slot).
> + This module can be found on Freescale Vybrid and LS-1 SoCs.
> +
> config DMA_ENGINE
> bool
>
> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
> index 0a6f08e..e39c56b 100644
> --- a/drivers/dma/Makefile
> +++ b/drivers/dma/Makefile
> @@ -43,3 +43,4 @@ obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o
> obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o
> obj-$(CONFIG_TI_CPPI41) += cppi41.o
> obj-$(CONFIG_K3_DMA) += k3dma.o
> +obj-$(CONFIG_FSL_EDMA) += fsl-edma.o
> diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
> new file mode 100644
> index 0000000..9025300
> --- /dev/null
> +++ b/drivers/dma/fsl-edma.c
> @@ -0,0 +1,975 @@
> +/*
> + * drivers/dma/fsl-edma.c
> + *
> + * Copyright 2013-2014 Freescale Semiconductor, Inc.
> + *
> + * Driver for the Freescale eDMA engine with flexible channel
> multiplexing
> + * capability for DMA request sources. The eDMA block can be found on
> some
> + * Vybrid and Layerscape SoCs.
> + *
> + * 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.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/clk.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/dmapool.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_dma.h>
> +
> +#include "virt-dma.h"
> +
> +#define EDMA_CR 0x00
> +#define EDMA_ES 0x04
> +#define EDMA_ERQ 0x0C
> +#define EDMA_EEI 0x14
> +#define EDMA_SERQ 0x1B
> +#define EDMA_CERQ 0x1A
> +#define EDMA_SEEI 0x19
> +#define EDMA_CEEI 0x18
> +#define EDMA_CINT 0x1F
> +#define EDMA_CERR 0x1E
> +#define EDMA_SSRT 0x1D
> +#define EDMA_CDNE 0x1C
> +#define EDMA_INTR 0x24
> +#define EDMA_ERR 0x2C
> +
> +#define EDMA_TCD_SADDR(x) (0x1000 + 32 * (x))
> +#define EDMA_TCD_SOFF(x) (0x1004 + 32 * (x))
> +#define EDMA_TCD_ATTR(x) (0x1006 + 32 * (x))
> +#define EDMA_TCD_NBYTES(x) (0x1008 + 32 * (x))
> +#define EDMA_TCD_SLAST(x) (0x100C + 32 * (x))
> +#define EDMA_TCD_DADDR(x) (0x1010 + 32 * (x))
> +#define EDMA_TCD_DOFF(x) (0x1014 + 32 * (x))
> +#define EDMA_TCD_CITER_ELINK(x) (0x1016 + 32 * (x))
> +#define EDMA_TCD_CITER(x) (0x1016 + 32 * (x))
> +#define EDMA_TCD_DLAST_SGA(x) (0x1018 + 32 * (x))
> +#define EDMA_TCD_CSR(x) (0x101C + 32 * (x))
> +#define EDMA_TCD_BITER_ELINK(x) (0x101E + 32 * (x))
> +#define EDMA_TCD_BITER(x) (0x101E + 32 * (x))
> +
> +#define EDMA_CR_EDBG BIT(1)
> +#define EDMA_CR_ERCA BIT(2)
> +#define EDMA_CR_ERGA BIT(3)
> +#define EDMA_CR_HOE BIT(4)
> +#define EDMA_CR_HALT BIT(5)
> +#define EDMA_CR_CLM BIT(6)
> +#define EDMA_CR_EMLM BIT(7)
> +#define EDMA_CR_ECX BIT(16)
> +#define EDMA_CR_CX BIT(17)
> +
> +#define EDMA_SEEI_SEEI(x) ((x) & 0x1F)
> +#define EDMA_CEEI_CEEI(x) ((x) & 0x1F)
> +#define EDMA_CINT_CINT(x) ((x) & 0x1F)
> +#define EDMA_CERR_CERR(x) ((x) & 0x1F)
> +
> +#define EDMA_TCD_ATTR_DSIZE(x) (((x) & 0x0007))
> +#define EDMA_TCD_ATTR_DMOD(x) (((x) & 0x001F) << 3)
> +#define EDMA_TCD_ATTR_SSIZE(x) (((x) & 0x0007) << 8)
> +#define EDMA_TCD_ATTR_SMOD(x) (((x) & 0x001F) << 11)
> +#define EDMA_TCD_ATTR_SSIZE_8BIT (0x0000)
> +#define EDMA_TCD_ATTR_SSIZE_16BIT (0x0100)
> +#define EDMA_TCD_ATTR_SSIZE_32BIT (0x0200)
> +#define EDMA_TCD_ATTR_SSIZE_64BIT (0x0300)
> +#define EDMA_TCD_ATTR_SSIZE_32BYTE (0x0500)
> +#define EDMA_TCD_ATTR_DSIZE_8BIT (0x0000)
> +#define EDMA_TCD_ATTR_DSIZE_16BIT (0x0001)
> +#define EDMA_TCD_ATTR_DSIZE_32BIT (0x0002)
> +#define EDMA_TCD_ATTR_DSIZE_64BIT (0x0003)
> +#define EDMA_TCD_ATTR_DSIZE_32BYTE (0x0005)
> +
> +#define EDMA_TCD_SOFF_SOFF(x) (x)
> +#define EDMA_TCD_NBYTES_NBYTES(x) (x)
> +#define EDMA_TCD_SLAST_SLAST(x) (x)
> +#define EDMA_TCD_DADDR_DADDR(x) (x)
> +#define EDMA_TCD_CITER_CITER(x) ((x) & 0x7FFF)
> +#define EDMA_TCD_DOFF_DOFF(x) (x)
> +#define EDMA_TCD_DLAST_SGA_DLAST_SGA(x) (x)
> +#define EDMA_TCD_BITER_BITER(x) ((x) & 0x7FFF)
> +
> +#define EDMA_TCD_CSR_START BIT(0)
> +#define EDMA_TCD_CSR_INT_MAJOR BIT(1)
> +#define EDMA_TCD_CSR_INT_HALF BIT(2)
> +#define EDMA_TCD_CSR_D_REQ BIT(3)
> +#define EDMA_TCD_CSR_E_SG BIT(4)
> +#define EDMA_TCD_CSR_E_LINK BIT(5)
> +#define EDMA_TCD_CSR_ACTIVE BIT(6)
> +#define EDMA_TCD_CSR_DONE BIT(7)
> +
> +#define EDMAMUX_CHCFG_DIS 0x0
> +#define EDMAMUX_CHCFG_ENBL 0x80
> +#define EDMAMUX_CHCFG_SOURCE(n) ((n) & 0x3F)
> +
> +#define DMAMUX_NR 2
> +
> +#define FSL_EDMA_BUSWIDTHS BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
> + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
> + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
> + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)
> +
> +struct fsl_edma_hw_tcd {
> + u32 saddr;
> + u16 soff;
> + u16 attr;
> + u32 nbytes;
> + u32 slast;
> + u32 daddr;
> + u16 doff;
> + u16 citer;
> + u32 dlast_sga;
> + u16 csr;
> + u16 biter;
> +};
> +
> +struct fsl_edma_sw_tcd {
> + dma_addr_t ptcd;
> + struct fsl_edma_hw_tcd *vtcd;
> +};
> +
> +struct fsl_edma_slave_config {
> + enum dma_transfer_direction dir;
> + enum dma_slave_buswidth addr_width;
> + u32 dev_addr;
> + u32 burst;
> + u32 attr;
> +};
> +
> +struct fsl_edma_chan {
> + struct virt_dma_chan vchan;
> + enum dma_status status;
> + struct fsl_edma_engine *edma;
> + struct fsl_edma_desc *edesc;
> + struct fsl_edma_slave_config fsc;
> + struct dma_pool *tcd_pool;
> +};
> +
> +struct fsl_edma_desc {
> + struct virt_dma_desc vdesc;
> + struct fsl_edma_chan *echan;
> + bool iscyclic;
> + unsigned int n_tcds;
> + struct fsl_edma_sw_tcd tcd[];
> +};
> +
> +struct fsl_edma_engine {
> + struct dma_device dma_dev;
> + void __iomem *membase;
> + void __iomem *muxbase[DMAMUX_NR];
> + struct clk *muxclk[DMAMUX_NR];
> + struct mutex fsl_edma_mutex;
> + u32 n_chans;
> + int txirq;
> + int errirq;
> + bool big_endian;
> + struct fsl_edma_chan chans[];
> +};
> +
> +/*
> + * R/W functions for big- or little-endian registers
> + * the eDMA controller's endian is independent of the CPU core's endian.
> + */
> +
> +static u16 edma_readw(struct fsl_edma_engine *edma, void __iomem *addr)
> +{
> + if (edma->big_endian)
> + return ioread16be(addr);
> + else
> + return ioread16(addr);
> +}
> +
> +static u32 edma_readl(struct fsl_edma_engine *edma, void __iomem *addr)
> +{
> + if (edma->big_endian)
> + return ioread32be(addr);
> + else
> + return ioread32(addr);
> +}
> +
> +static void edma_writeb(struct fsl_edma_engine *edma, u8 val, void
> __iomem *addr)
> +{
> + iowrite8(val, addr);
> +}
> +
> +static void edma_writew(struct fsl_edma_engine *edma, u16 val, void
> __iomem *addr)
> +{
> + if (edma->big_endian)
> + iowrite16be(val, addr);
> + else
> + iowrite16(val, addr);
> +}
> +
> +static void edma_writel(struct fsl_edma_engine *edma, u32 val, void
> __iomem *addr)
> +{
> + if (edma->big_endian)
> + iowrite32be(val, addr);
> + else
> + iowrite32(val, addr);
> +}
> +
> +static struct fsl_edma_chan *to_fsl_edma_chan(struct dma_chan *chan)
> +{
> + return container_of(chan, struct fsl_edma_chan, vchan.chan);
> +}
> +
> +static struct fsl_edma_desc *to_fsl_edma_desc(struct virt_dma_desc *vd)
> +{
> + return container_of(vd, struct fsl_edma_desc, vdesc);
> +}
> +
> +static void fsl_edma_enable_request(struct fsl_edma_chan *fsl_chan)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + edma_writeb(fsl_chan->edma, EDMA_SEEI_SEEI(ch), addr + EDMA_SEEI);
> + edma_writeb(fsl_chan->edma, ch, addr + EDMA_SERQ);
> +}
> +
> +static void fsl_edma_disable_request(struct fsl_edma_chan *fsl_chan)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + edma_writeb(fsl_chan->edma, ch, addr + EDMA_CERQ);
> + edma_writeb(fsl_chan->edma, EDMA_CEEI_CEEI(ch), addr + EDMA_CEEI);
> +}
> +
> +static void fsl_edma_chan_mux(struct fsl_edma_chan *fsl_chan,
> + unsigned int slot, bool enable)
> +{
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> + void __iomem *muxaddr = fsl_chan->edma->muxbase[ch / DMAMUX_NR];
> + unsigned chans_per_mux, ch_off;
> +
> + chans_per_mux = fsl_chan->edma->n_chans / DMAMUX_NR;
> + ch_off = fsl_chan->vchan.chan.chan_id % chans_per_mux;
> +
> + if (enable)
> + edma_writeb(fsl_chan->edma,
> + EDMAMUX_CHCFG_ENBL | EDMAMUX_CHCFG_SOURCE(slot),
> + muxaddr + ch_off);
> + else
> + edma_writeb(fsl_chan->edma, EDMAMUX_CHCFG_DIS, muxaddr +
> ch_off);
> +}
> +
> +static unsigned int fsl_edma_get_tcd_attr(enum dma_slave_buswidth
> addr_width)
> +{
> + switch (addr_width) {
> + case 1:
> + return EDMA_TCD_ATTR_SSIZE_8BIT | EDMA_TCD_ATTR_DSIZE_8BIT;
> + case 2:
> + return EDMA_TCD_ATTR_SSIZE_16BIT | EDMA_TCD_ATTR_DSIZE_16BIT;
> + case 4:
> + return EDMA_TCD_ATTR_SSIZE_32BIT | EDMA_TCD_ATTR_DSIZE_32BIT;
> + case 8:
> + return EDMA_TCD_ATTR_SSIZE_64BIT | EDMA_TCD_ATTR_DSIZE_64BIT;
> + default:
> + return EDMA_TCD_ATTR_SSIZE_32BIT | EDMA_TCD_ATTR_DSIZE_32BIT;
> + }
> +}
> +
> +static void fsl_edma_free_desc(struct virt_dma_desc *vdesc)
> +{
> + struct fsl_edma_desc *fsl_desc;
> + int i;
> +
> + fsl_desc = to_fsl_edma_desc(vdesc);
> + for (i = 0; i < fsl_desc->n_tcds; i++)
> + dma_pool_free(fsl_desc->echan->tcd_pool,
> + fsl_desc->tcd[i].vtcd,
> + fsl_desc->tcd[i].ptcd);
> + kfree(fsl_desc);
> +}
> +
> +static int fsl_edma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
> + unsigned long arg)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct dma_slave_config *cfg = (void *)arg;
> + unsigned long flags;
> + LIST_HEAD(head);
> +
> + switch (cmd) {
> + case DMA_TERMINATE_ALL:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + fsl_edma_disable_request(fsl_chan);
> + fsl_chan->edesc = NULL;
> + vchan_get_all_descriptors(&fsl_chan->vchan, &head);
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
> + return 0;
> +
> + case DMA_SLAVE_CONFIG:
> + fsl_chan->fsc.dir = cfg->direction;
> + if (cfg->direction == DMA_DEV_TO_MEM) {
> + fsl_chan->fsc.dev_addr = cfg->src_addr;
> + fsl_chan->fsc.addr_width = cfg->src_addr_width;
> + fsl_chan->fsc.burst = cfg->src_maxburst;
> + fsl_chan->fsc.attr = fsl_edma_get_tcd_attr(cfg-
> >src_addr_width);
> + } else if (cfg->direction == DMA_MEM_TO_DEV) {
> + fsl_chan->fsc.dev_addr = cfg->dst_addr;
> + fsl_chan->fsc.addr_width = cfg->dst_addr_width;
> + fsl_chan->fsc.burst = cfg->dst_maxburst;
> + fsl_chan->fsc.attr = fsl_edma_get_tcd_attr(cfg-
> >dst_addr_width);
> + } else {
> + return -EINVAL;
> + }
> + return 0;
> +
> + case DMA_PAUSE:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + if (fsl_chan->edesc) {
> + fsl_edma_disable_request(fsl_chan);
> + fsl_chan->status = DMA_PAUSED;
> + }
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + return 0;
> +
> + case DMA_RESUME:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + if (fsl_chan->edesc) {
> + fsl_edma_enable_request(fsl_chan);
> + fsl_chan->status = DMA_IN_PROGRESS;
> + }
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + return 0;
> +
> + default:
> + return -ENXIO;
> + }
> +}
> +
> +static size_t fsl_edma_desc_residue(struct fsl_edma_chan *fsl_chan,
> + struct virt_dma_desc *vdesc, bool in_progress)
> +{
> + struct fsl_edma_desc *edesc = fsl_chan->edesc;
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> + enum dma_transfer_direction dir = fsl_chan->fsc.dir;
> + dma_addr_t cur_addr, dma_addr;
> + size_t len, size;
> + int i;
> +
> + /* calculate the total size in this desc */
> + for (len = i = 0; i < fsl_chan->edesc->n_tcds; i++)
> + len += edma_readl(fsl_chan->edma, &(edesc->tcd[i].vtcd-
> >nbytes))
> + * edma_readw(fsl_chan->edma, &(edesc->tcd[i].vtcd-
> >biter));
> +
> + if (!in_progress)
> + return len;
> +
> + if (dir == DMA_MEM_TO_DEV)
> + cur_addr = edma_readl(fsl_chan->edma, addr +
> EDMA_TCD_SADDR(ch));
> + else
> + cur_addr = edma_readl(fsl_chan->edma, addr +
> EDMA_TCD_DADDR(ch));
> +
> + /* figure out the finished and calculate the residue */
> + for (i = 0; i < fsl_chan->edesc->n_tcds; i++) {
> + size = edma_readl(fsl_chan->edma, &(edesc->tcd[i].vtcd-
> >nbytes))
> + * edma_readw(fsl_chan->edma, &(edesc->tcd[i].vtcd-
> >biter));
> + if (dir == DMA_MEM_TO_DEV)
> + dma_addr = edma_readl(fsl_chan->edma,
> + &(edesc->tcd[i].vtcd->saddr));
> + else
> + dma_addr = edma_readl(fsl_chan->edma,
> + &(edesc->tcd[i].vtcd->daddr));
> +
> + len -= size;
> + if (cur_addr > dma_addr && cur_addr < dma_addr + size) {
> + len += dma_addr + size - cur_addr;
> + break;
> + }
> + }
> +
> + return len;
> +}
> +
> +static enum dma_status fsl_edma_tx_status(struct dma_chan *chan,
> + dma_cookie_t cookie, struct dma_tx_state *txstate)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct virt_dma_desc *vdesc;
> + enum dma_status status;
> + unsigned long flags;
> +
> + status = dma_cookie_status(chan, cookie, txstate);
> + if (status == DMA_COMPLETE)
> + return status;
> +
> + if (!txstate)
> + return fsl_chan->status;
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + vdesc = vchan_find_desc(&fsl_chan->vchan, cookie);
> + if (fsl_chan->edesc && cookie == fsl_chan->edesc->vdesc.tx.cookie)
> + txstate->residue = fsl_edma_desc_residue(fsl_chan, vdesc,
> true);
> + else if (vdesc)
> + txstate->residue = fsl_edma_desc_residue(fsl_chan, vdesc,
> false);
> + else
> + txstate->residue = 0;
> +
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +
> + return fsl_chan->status;
> +}
> +
> +static void fsl_edma_set_tcd_params(struct fsl_edma_chan *fsl_chan,
> + u32 src, u32 dst, u16 attr, u16 soff, u32 nbytes,
> + u32 slast, u16 citer, u16 biter, u32 doff, u32 dlast_sga,
> + u16 csr)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + /*
> + * TCD parameters have been swapped in fill_tcd_params(),
> + * so just write them to registers in the cpu endian here
> + */
> + writew(0, addr + EDMA_TCD_CSR(ch));
> + writel(src, addr + EDMA_TCD_SADDR(ch));
> + writel(dst, addr + EDMA_TCD_DADDR(ch));
> + writew(attr, addr + EDMA_TCD_ATTR(ch));
> + writew(soff, addr + EDMA_TCD_SOFF(ch));
> + writel(nbytes, addr + EDMA_TCD_NBYTES(ch));
> + writel(slast, addr + EDMA_TCD_SLAST(ch));
> + writew(citer, addr + EDMA_TCD_CITER(ch));
> + writew(biter, addr + EDMA_TCD_BITER(ch));
> + writew(doff, addr + EDMA_TCD_DOFF(ch));
> + writel(dlast_sga, addr + EDMA_TCD_DLAST_SGA(ch));
> + writew(csr, addr + EDMA_TCD_CSR(ch));
> +}
> +
> +static void fill_tcd_params(struct fsl_edma_engine *edma,
> + struct fsl_edma_hw_tcd *tcd, u32 src, u32 dst,
> + u16 attr, u16 soff, u32 nbytes, u32 slast, u16 citer,
> + u16 biter, u16 doff, u32 dlast_sga, bool major_int,
> + bool disable_req, bool enable_sg)
> +{
> + u16 csr = 0;
> +
> + /*
> + * eDMA hardware SGs require the TCD parameters stored in memory
> + * the same endian as the eDMA module so that they can be loaded
> + * automatically by the engine
> + */
> + edma_writel(edma, src, &(tcd->saddr));
> + edma_writel(edma, dst, &(tcd->daddr));
> + edma_writew(edma, attr, &(tcd->attr));
> + edma_writew(edma, EDMA_TCD_SOFF_SOFF(soff), &(tcd->soff));
> + edma_writel(edma, EDMA_TCD_NBYTES_NBYTES(nbytes), &(tcd->nbytes));
> + edma_writel(edma, EDMA_TCD_SLAST_SLAST(slast), &(tcd->slast));
> + edma_writew(edma, EDMA_TCD_CITER_CITER(citer), &(tcd->citer));
> + edma_writew(edma, EDMA_TCD_DOFF_DOFF(doff), &(tcd->doff));
> + edma_writel(edma, EDMA_TCD_DLAST_SGA_DLAST_SGA(dlast_sga), &(tcd-
> >dlast_sga));
> + edma_writew(edma, EDMA_TCD_BITER_BITER(biter), &(tcd->biter));
> + if (major_int)
> + csr |= EDMA_TCD_CSR_INT_MAJOR;
> +
> + if (disable_req)
> + csr |= EDMA_TCD_CSR_D_REQ;
> +
> + if (enable_sg)
> + csr |= EDMA_TCD_CSR_E_SG;
> +
> + edma_writew(edma, csr, &(tcd->csr));
> +}
> +
> +static struct fsl_edma_desc *fsl_edma_alloc_desc(struct fsl_edma_chan
> *fsl_chan,
> + int sg_len)
> +{
> + struct fsl_edma_desc *fsl_desc;
> + int i;
> +
> + fsl_desc = kzalloc(sizeof(*fsl_desc) + sizeof(struct
> fsl_edma_sw_tcd) * sg_len,
> + GFP_NOWAIT);
> + if (!fsl_desc)
> + return NULL;
> +
> + fsl_desc->echan = fsl_chan;
> + fsl_desc->n_tcds = sg_len;
> + for (i = 0; i < sg_len; i++) {
> + fsl_desc->tcd[i].vtcd = dma_pool_alloc(fsl_chan->tcd_pool,
> + GFP_NOWAIT, &fsl_desc->tcd[i].ptcd);
> + if (!fsl_desc->tcd[i].vtcd)
> + goto err;
> + }
> + return fsl_desc;
> +
> +err:
> + while (--i >= 0)
> + dma_pool_free(fsl_chan->tcd_pool, fsl_desc->tcd[i].vtcd,
> + fsl_desc->tcd[i].ptcd);
> + kfree(fsl_desc);
> + return NULL;
> +}
> +
> +static struct dma_async_tx_descriptor *fsl_edma_prep_dma_cyclic(
> + struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
> + size_t period_len, enum dma_transfer_direction direction,
> + unsigned long flags, void *context)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct fsl_edma_desc *fsl_desc;
> + dma_addr_t dma_buf_next;
> + int sg_len, i;
> + u32 src_addr, dst_addr, last_sg, nbytes;
> + u16 soff, doff, iter;
> +
> + if (!is_slave_direction(fsl_chan->fsc.dir))
> + return NULL;
> +
> + sg_len = buf_len / period_len;
> + fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
> + if (!fsl_desc)
> + return NULL;
> + fsl_desc->iscyclic = true;
> +
> + dma_buf_next = dma_addr;
> + nbytes = fsl_chan->fsc.addr_width * fsl_chan->fsc.burst;
> + iter = period_len / nbytes;
> +
> + for (i = 0; i < sg_len; i++) {
> + if (dma_buf_next >= dma_addr + buf_len)
> + dma_buf_next = dma_addr;
> +
> + /* get next sg's physical address */
> + last_sg = fsl_desc->tcd[(i + 1) % sg_len].ptcd;
> +
> + if (fsl_chan->fsc.dir == DMA_MEM_TO_DEV) {
> + src_addr = dma_buf_next;
> + dst_addr = fsl_chan->fsc.dev_addr;
> + soff = fsl_chan->fsc.addr_width;
> + doff = 0;
> + } else {
> + src_addr = fsl_chan->fsc.dev_addr;
> + dst_addr = dma_buf_next;
> + soff = 0;
> + doff = fsl_chan->fsc.addr_width;
> + }
> +
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> src_addr,
> + dst_addr, fsl_chan->fsc.attr, soff, nbytes, 0,
> + iter, iter, doff, last_sg, true, false, true);
> + dma_buf_next += period_len;
> + }
> +
> + return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
> +}
> +
> +static struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg(
> + struct dma_chan *chan, struct scatterlist *sgl,
> + unsigned int sg_len, enum dma_transfer_direction direction,
> + unsigned long flags, void *context)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct fsl_edma_desc *fsl_desc;
> + struct scatterlist *sg;
> + u32 src_addr, dst_addr, last_sg, nbytes;
> + u16 soff, doff, iter;
> + int i;
> +
> + if (!is_slave_direction(fsl_chan->fsc.dir))
> + return NULL;
> +
> + fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
> + if (!fsl_desc)
> + return NULL;
> + fsl_desc->iscyclic = false;
> +
> + nbytes = fsl_chan->fsc.addr_width * fsl_chan->fsc.burst;
> + for_each_sg(sgl, sg, sg_len, i) {
> + /* get next sg's physical address */
> + last_sg = fsl_desc->tcd[(i + 1) % sg_len].ptcd;
> +
> + if (fsl_chan->fsc.dir == DMA_MEM_TO_DEV) {
> + src_addr = sg_dma_address(sg);
> + dst_addr = fsl_chan->fsc.dev_addr;
> + soff = fsl_chan->fsc.addr_width;
> + doff = 0;
> + } else {
> + src_addr = fsl_chan->fsc.dev_addr;
> + dst_addr = sg_dma_address(sg);
> + soff = 0;
> + doff = fsl_chan->fsc.addr_width;
> + }
> +
> + iter = sg_dma_len(sg) / nbytes;
> + if (i < sg_len - 1) {
> + last_sg = fsl_desc->tcd[(i + 1)].ptcd;
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> + src_addr, dst_addr, fsl_chan->fsc.attr,
> + soff, nbytes, 0, iter, iter, doff, last_sg,
> + false, false, true);
> + } else {
> + last_sg = 0;
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> + src_addr, dst_addr, fsl_chan->fsc.attr,
> + soff, nbytes, 0, iter, iter, doff, last_sg,
> + true, true, false);
> + }
> + }
> +
> + return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
> +}
> +
> +static void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan)
> +{
> + struct fsl_edma_hw_tcd *tcd;
> + struct virt_dma_desc *vdesc;
> +
> + vdesc = vchan_next_desc(&fsl_chan->vchan);
> + if (!vdesc)
> + return;
> + fsl_chan->edesc = to_fsl_edma_desc(vdesc);
> + tcd = fsl_chan->edesc->tcd[0].vtcd;
> + fsl_edma_set_tcd_params(fsl_chan, tcd->saddr, tcd->daddr, tcd->attr,
> + tcd->soff, tcd->nbytes, tcd->slast, tcd->citer,
> + tcd->biter, tcd->doff, tcd->dlast_sga, tcd->csr);
> + fsl_edma_enable_request(fsl_chan);
> + fsl_chan->status = DMA_IN_PROGRESS;
> +}
> +
> +static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
> +{
> + struct fsl_edma_engine *fsl_edma = dev_id;
> + unsigned int intr, ch;
> + void __iomem *base_addr;
> + struct fsl_edma_chan *fsl_chan;
> +
> + base_addr = fsl_edma->membase;
> +
> + intr = edma_readl(fsl_edma, base_addr + EDMA_INTR);
> + if (!intr)
> + return IRQ_NONE;
> +
> + for (ch = 0; ch < fsl_edma->n_chans; ch++) {
> + if (intr & (0x1 << ch)) {
> + edma_writeb(fsl_edma, EDMA_CINT_CINT(ch),
> + base_addr + EDMA_CINT);
> +
> + fsl_chan = &fsl_edma->chans[ch];
> +
> + spin_lock(&fsl_chan->vchan.lock);
> + if (!fsl_chan->edesc->iscyclic) {
> + list_del(&fsl_chan->edesc->vdesc.node);
> + vchan_cookie_complete(&fsl_chan->edesc->vdesc);
> + fsl_chan->edesc = NULL;
> + fsl_chan->status = DMA_COMPLETE;
> + } else {
> + vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
> + }
> +
> + if (!fsl_chan->edesc)
> + fsl_edma_xfer_desc(fsl_chan);
> +
> + spin_unlock(&fsl_chan->vchan.lock);
> + }
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
> +{
> + struct fsl_edma_engine *fsl_edma = dev_id;
> + unsigned int err, ch;
> +
> + err = edma_readl(fsl_edma, fsl_edma->membase + EDMA_ERR);
> + if (!err)
> + return IRQ_NONE;
> +
> + for (ch = 0; ch < fsl_edma->n_chans; ch++) {
> + if (err & (0x1 << ch)) {
> + fsl_edma_disable_request(&fsl_edma->chans[ch]);
> + edma_writeb(fsl_edma, EDMA_CERR_CERR(ch),
> + fsl_edma->membase + EDMA_CERR);
> + fsl_edma->chans[ch].status = DMA_ERROR;
> + }
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
> +{
> + if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
> + return IRQ_HANDLED;
> +
> + return fsl_edma_err_handler(irq, dev_id);
> +}
> +
> +static void fsl_edma_issue_pending(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> +
> + if (vchan_issue_pending(&fsl_chan->vchan) && !fsl_chan->edesc)
> + fsl_edma_xfer_desc(fsl_chan);
> +
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +}
> +
> +static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
> + struct of_dma *ofdma)
> +{
> + struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
> + struct dma_chan *chan;
> +
> + if (dma_spec->args_count != 2)
> + return NULL;
> +
> + mutex_lock(&fsl_edma->fsl_edma_mutex);
> + list_for_each_entry(chan, &fsl_edma->dma_dev.channels, device_node)
> {
> + if (chan->client_count)
> + continue;
> + if ((chan->chan_id / DMAMUX_NR) == dma_spec->args[0]) {
> + chan = dma_get_slave_channel(chan);
> + if (chan) {
> + chan->device->privatecnt++;
> + fsl_edma_chan_mux(to_fsl_edma_chan(chan),
> + dma_spec->args[1], true);
> + mutex_unlock(&fsl_edma->fsl_edma_mutex);
> + return chan;
> + }
> + }
> + }
> + mutex_unlock(&fsl_edma->fsl_edma_mutex);
> + return NULL;
> +}
> +
> +static int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> +
> + fsl_chan->tcd_pool = dma_pool_create("tcd_pool", chan->device->dev,
> + sizeof(struct fsl_edma_hw_tcd),
> + 32, 0);
> + return 0;
> +}
> +
> +static void fsl_edma_free_chan_resources(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + unsigned long flags;
> + LIST_HEAD(head);
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + fsl_edma_disable_request(fsl_chan);
> + fsl_edma_chan_mux(fsl_chan, 0, false);
> + fsl_chan->edesc = NULL;
> + vchan_get_all_descriptors(&fsl_chan->vchan, &head);
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +
> + vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
> + dma_pool_destroy(fsl_chan->tcd_pool);
> + fsl_chan->tcd_pool = NULL;
> +}
> +
> +static int fsl_dma_device_slave_caps(struct dma_chan *dchan,
> + struct dma_slave_caps *caps)
> +{
> + caps->src_addr_widths = FSL_EDMA_BUSWIDTHS;
> + caps->dstn_addr_widths = FSL_EDMA_BUSWIDTHS;
> + caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
> + caps->cmd_pause = true;
> + caps->cmd_terminate = true;
> +
> + return 0;
> +}
> +
> +static int
> +fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine
> *fsl_edma)
> +{
> + int ret;
> +
> + fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
> + if (fsl_edma->txirq < 0) {
> + dev_err(&pdev->dev, "Can't get edma-tx irq.\n");
> + return fsl_edma->txirq;
> + }
> +
> + fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
> + if (fsl_edma->errirq < 0) {
> + dev_err(&pdev->dev, "Can't get edma-err irq.\n");
> + return fsl_edma->errirq;
> + }
> +
> + if (fsl_edma->txirq == fsl_edma->errirq) {
> + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
> + fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
> + return ret;
> + }
> + } else {
> + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
> + fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
> + return ret;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
> + fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int fsl_edma_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct fsl_edma_engine *fsl_edma;
> + struct fsl_edma_chan *fsl_chan;
> + struct resource *res;
> + int len, chans;
> + int ret, i;
> +
> + ret = of_property_read_u32(np, "dma-channels", &chans);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't get dma-channels.\n");
> + return ret;
> + }
> +
> + len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
> + fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
> + if (!fsl_edma)
> + return -ENOMEM;
> +
> + fsl_edma->n_chans = chans;
> + mutex_init(&fsl_edma->fsl_edma_mutex);
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + fsl_edma->membase = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(fsl_edma->membase))
> + return PTR_ERR(fsl_edma->membase);
> +
> + for (i = 0; i < DMAMUX_NR; i++) {
> + char clkname[32];
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
> + fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(fsl_edma->muxbase[i]))
> + return PTR_ERR(fsl_edma->muxbase[i]);
> +
> + sprintf(clkname, "dmamux%d", i);
> + fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
> + if (IS_ERR(fsl_edma->muxclk[i])) {
> + dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
> + return PTR_ERR(fsl_edma->muxclk[i]);
> + }
> +
> + ret = clk_prepare_enable(fsl_edma->muxclk[i]);
> + if (ret) {
> + dev_err(&pdev->dev, "DMAMUX clk block failed.\n");
> + return ret;
> + }
> +
> + }
> +
> + ret = fsl_edma_irq_init(pdev, fsl_edma);
> + if (ret)
> + return ret;
> +
> + fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
> +
> + INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
> + for (i = 0; i < fsl_edma->n_chans; i++) {
> + struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
> +
> + fsl_chan->edma = fsl_edma;
> +
> + fsl_chan->vchan.desc_free = fsl_edma_free_desc;
> + vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
> +
> + edma_writew(fsl_edma, 0x0, fsl_edma->membase +
> EDMA_TCD_CSR(i));
> + fsl_edma_chan_mux(fsl_chan, 0, false);
> + }
> +
> + dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
> + dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
> + dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
> +
> + fsl_edma->dma_dev.dev = &pdev->dev;
> + fsl_edma->dma_dev.device_alloc_chan_resources
> + = fsl_edma_alloc_chan_resources;
> + fsl_edma->dma_dev.device_free_chan_resources
> + = fsl_edma_free_chan_resources;
> + fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
> + fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
> + fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
> + fsl_edma->dma_dev.device_control = fsl_edma_control;
> + fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
> + fsl_edma->dma_dev.device_slave_caps = fsl_dma_device_slave_caps;
> +
> + platform_set_drvdata(pdev, fsl_edma);
> +
> + ret = dma_async_device_register(&fsl_edma->dma_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register Freescale eDMA
> engine.\n");
> + return ret;
> + }
> +
> + ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register Freescale eDMA
> of_dma.\n");
> + dma_async_device_unregister(&fsl_edma->dma_dev);
> + return ret;
> + }
> +
> + /* enable round robin arbitration */
> + edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, fsl_edma-
> >membase + EDMA_CR);
> +
> + return 0;
> +}
> +
> +static int fsl_edma_remove(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
> + int i;
> +
> + of_dma_controller_free(np);
> + dma_async_device_unregister(&fsl_edma->dma_dev);
> +
> + for (i = 0; i < DMAMUX_NR; i++)
> + clk_disable_unprepare(fsl_edma->muxclk[i]);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id fsl_edma_dt_ids[] = {
> + { .compatible = "fsl,vf610-edma", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
> +
> +static struct platform_driver fsl_edma_driver = {
> + .driver = {
> + .name = "fsl-edma",
> + .owner = THIS_MODULE,
> + .of_match_table = fsl_edma_dt_ids,
> + },
> + .probe = fsl_edma_probe,
> + .remove = fsl_edma_remove,
> +};
> +
> +module_platform_driver(fsl_edma_driver);
> +
> +MODULE_ALIAS("platform:fsl-edma");
> +MODULE_DESCRIPTION("Freescale eDMA engine driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.8.0
>

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