/* * Renesas USB DMA Controller Driver * * Copyright (C) 2015 Renesas Electronics Corporation * * based on rcar-dmac.c * Copyright (C) 2014 Renesas Electronics Inc. * Author: Laurent Pinchart * * This is free software; you can redistribute it and/or modify * it under the terms of version 2 of the GNU General Public License as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "../dmaengine.h" #include "../virt-dma.h" /* * struct usb_dmac_sg - Descriptor for a hardware transfer * @mem_addr: memory address * @size: transfer size in bytes */ struct usb_dmac_sg { dma_addr_t mem_addr; u32 size; }; /* * struct usb_dmac_desc - USB DMA Transfer Descriptor * @vd: base virtual channel DMA transaction descriptor * @direction: direction of the DMA transfer * @sg_allocated_len: length of allocated sg * @sg_len: length of sg * @sg_index: index of sg * @residue: residue after the DMAC completed a transfer * @node: node for desc_got and desc_freed * @done_cookie: cookie after the DMAC completed a transfer * @sg: information for the transfer */ struct usb_dmac_desc { struct virt_dma_desc vd; enum dma_transfer_direction direction; unsigned int sg_allocated_len; unsigned int sg_len; unsigned int sg_index; u32 residue; struct list_head node; dma_cookie_t done_cookie; struct usb_dmac_sg sg[0]; }; #define to_usb_dmac_desc(vd) container_of(vd, struct usb_dmac_desc, vd) /* * struct usb_dmac_chan - USB DMA Controller Channel * @vc: base virtual DMA channel object * @iomem: channel I/O memory base * @index: index of this channel in the controller * @irq: irq number of this channel * @desc: the current descriptor * @descs_allocated: number of descriptors allocated * @desc_got: got descriptors * @desc_freed: freed descriptors after the DMAC completed a transfer */ struct usb_dmac_chan { struct virt_dma_chan vc; void __iomem *iomem; unsigned int index; int irq; struct usb_dmac_desc *desc; int descs_allocated; struct list_head desc_got; struct list_head desc_freed; }; #define to_usb_dmac_chan(c) container_of(c, struct usb_dmac_chan, vc.chan) /* * struct usb_dmac - USB DMA Controller * @engine: base DMA engine object * @dev: the hardware device * @iomem: remapped I/O memory base * @n_channels: number of available channels * @channels: array of DMAC channels */ struct usb_dmac { struct dma_device engine; struct device *dev; void __iomem *iomem; unsigned int n_channels; struct usb_dmac_chan *channels; }; #define to_usb_dmac(d) container_of(d, struct usb_dmac, engine) /* ----------------------------------------------------------------------------- * Registers */ #define USB_DMAC_CHAN_OFFSET(i) (0x20 + 0x20 * (i)) #define USB_DMASWR 0x0008 #define USB_DMASWR_SWR (1 << 0) #define USB_DMAOR 0x0060 #define USB_DMAOR_AE (1 << 2) #define USB_DMAOR_DME (1 << 0) #define USB_DMASAR 0x0000 #define USB_DMADAR 0x0004 #define USB_DMATCR 0x0008 #define USB_DMATCR_MASK 0x00ffffff #define USB_DMACHCR 0x0014 #define USB_DMACHCR_FTE (1 << 24) #define USB_DMACHCR_NULLE (1 << 16) #define USB_DMACHCR_NULL (1 << 12) #define USB_DMACHCR_TS_8B ((0 << 7) | (0 << 6)) #define USB_DMACHCR_TS_16B ((0 << 7) | (1 << 6)) #define USB_DMACHCR_TS_32B ((1 << 7) | (0 << 6)) #define USB_DMACHCR_IE (1 << 5) #define USB_DMACHCR_SP (1 << 2) #define USB_DMACHCR_TE (1 << 1) #define USB_DMACHCR_DE (1 << 0) #define USB_DMATEND 0x0018 /* Hardcode the xfer_shift to 5 (32bytes) */ #define USB_DMAC_XFER_SHIFT 5 #define USB_DMAC_XFER_SIZE (1 << USB_DMAC_XFER_SHIFT) #define USB_DMAC_CHCR_TS USB_DMACHCR_TS_32B #define USB_DMAC_SLAVE_BUSWIDTH DMA_SLAVE_BUSWIDTH_32_BYTES /* for descriptors */ #define USB_DMAC_INITIAL_NR_DESC 16 #define USB_DMAC_INITIAL_NR_SG 8 /* ----------------------------------------------------------------------------- * Device access */ static void usb_dmac_write(struct usb_dmac *dmac, u32 reg, u32 data) { writel(data, dmac->iomem + reg); } static u32 usb_dmac_read(struct usb_dmac *dmac, u32 reg) { return readl(dmac->iomem + reg); } static u32 usb_dmac_chan_read(struct usb_dmac_chan *chan, u32 reg) { return readl(chan->iomem + reg); } static void usb_dmac_chan_write(struct usb_dmac_chan *chan, u32 reg, u32 data) { writel(data, chan->iomem + reg); } /* ----------------------------------------------------------------------------- * Initialization and configuration */ static bool usb_dmac_chan_is_busy(struct usb_dmac_chan *chan) { u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR); return (chcr & (USB_DMACHCR_DE | USB_DMACHCR_TE)) == USB_DMACHCR_DE; } static u32 usb_dmac_calc_tend(u32 size) { /* * Please refer to the Figure "Example of Final Transaction Valid * Data Transfer Enable (EDTEN) Setting" in the data sheet. */ return 0xffffffff << (32 - (size % USB_DMAC_XFER_SIZE ? : USB_DMAC_XFER_SIZE)); } /* This function is already held by vc.lock */ static void usb_dmac_chan_start_sg(struct usb_dmac_chan *chan, unsigned int index) { struct usb_dmac_desc *desc = chan->desc; struct usb_dmac_sg *sg = desc->sg + index; dma_addr_t src_addr = 0, dst_addr = 0; WARN_ON_ONCE(usb_dmac_chan_is_busy(chan)); if (desc->direction == DMA_DEV_TO_MEM) dst_addr = sg->mem_addr; else src_addr = sg->mem_addr; dev_dbg(chan->vc.chan.device->dev, "chan%u: queue sg %p: %u@%pad -> %pad\n", chan->index, sg, sg->size, &src_addr, &dst_addr); usb_dmac_chan_write(chan, USB_DMASAR, src_addr & 0xffffffff); usb_dmac_chan_write(chan, USB_DMADAR, dst_addr & 0xffffffff); usb_dmac_chan_write(chan, USB_DMATCR, DIV_ROUND_UP(sg->size, USB_DMAC_XFER_SIZE)); usb_dmac_chan_write(chan, USB_DMATEND, usb_dmac_calc_tend(sg->size)); usb_dmac_chan_write(chan, USB_DMACHCR, USB_DMAC_CHCR_TS | USB_DMACHCR_NULLE | USB_DMACHCR_IE | USB_DMACHCR_DE); } /* This function is already held by vc.lock */ static void usb_dmac_chan_start_desc(struct usb_dmac_chan *chan) { struct virt_dma_desc *vd; vd = vchan_next_desc(&chan->vc); if (!vd) { chan->desc = NULL; return; } /* * Remove this request from vc->desc_issued. Otherwise, this driver * will get the previous value from vchan_next_desc() after a transfer * was completed. */ list_del(&vd->node); chan->desc = to_usb_dmac_desc(vd); chan->desc->sg_index = 0; usb_dmac_chan_start_sg(chan, 0); } static int usb_dmac_init(struct usb_dmac *dmac) { u16 dmaor; /* Clear all channels and enable the DMAC globally. */ usb_dmac_write(dmac, USB_DMAOR, USB_DMAOR_DME); dmaor = usb_dmac_read(dmac, USB_DMAOR); if ((dmaor & (USB_DMAOR_AE | USB_DMAOR_DME)) != USB_DMAOR_DME) { dev_warn(dmac->dev, "DMAOR initialization failed.\n"); return -EIO; } return 0; } /* ----------------------------------------------------------------------------- * Descriptors allocation and free */ static int usb_dmac_desc_alloc(struct usb_dmac_chan *chan, unsigned int sg_len, gfp_t gfp) { struct usb_dmac_desc *desc; unsigned long flags; desc = kzalloc(sizeof(*desc) + sg_len * sizeof(desc->sg[0]), gfp); if (!desc) return -ENOMEM; desc->sg_allocated_len = sg_len; INIT_LIST_HEAD(&desc->node); spin_lock_irqsave(&chan->vc.lock, flags); list_add_tail(&desc->node, &chan->desc_freed); spin_unlock_irqrestore(&chan->vc.lock, flags); return 0; } static void usb_dmac_desc_free(struct usb_dmac_chan *chan) { struct usb_dmac_desc *desc, *_desc; LIST_HEAD(list); list_splice_init(&chan->desc_freed, &list); list_splice_init(&chan->desc_got, &list); list_for_each_entry_safe(desc, _desc, &list, node) { list_del(&desc->node); kfree(desc); } chan->descs_allocated = 0; } static struct usb_dmac_desc *usb_dmac_desc_get(struct usb_dmac_chan *chan, unsigned int sg_len, gfp_t gfp) { struct usb_dmac_desc *desc = NULL; unsigned long flags; /* Get a freed descritpor */ spin_lock_irqsave(&chan->vc.lock, flags); list_for_each_entry(desc, &chan->desc_freed, node) { if (sg_len <= desc->sg_allocated_len) { list_move_tail(&desc->node, &chan->desc_got); spin_unlock_irqrestore(&chan->vc.lock, flags); return desc; } } spin_unlock_irqrestore(&chan->vc.lock, flags); /* Allocate a new descriptor */ if (!usb_dmac_desc_alloc(chan, sg_len, gfp)) { /* If allocated the desc, it was added to tail of the list */ spin_lock_irqsave(&chan->vc.lock, flags); desc = list_last_entry(&chan->desc_freed, struct usb_dmac_desc, node); list_move_tail(&desc->node, &chan->desc_got); spin_unlock_irqrestore(&chan->vc.lock, flags); return desc; } return NULL; } static void usb_dmac_desc_put(struct usb_dmac_chan *chan, struct usb_dmac_desc *desc) { unsigned long flags; spin_lock_irqsave(&chan->vc.lock, flags); list_move_tail(&desc->node, &chan->desc_freed); spin_unlock_irqrestore(&chan->vc.lock, flags); } /* ----------------------------------------------------------------------------- * Stop and reset */ static void usb_dmac_soft_reset(struct usb_dmac_chan *uchan) { struct dma_chan *chan = &uchan->vc.chan; struct usb_dmac *dmac = to_usb_dmac(chan->device); int i; /* Don't issue soft reset if any one of channels is busy */ for (i = 0; i < dmac->n_channels; ++i) { if (usb_dmac_chan_is_busy(uchan)) return; } usb_dmac_write(dmac, USB_DMAOR, 0); usb_dmac_write(dmac, USB_DMASWR, USB_DMASWR_SWR); udelay(100); usb_dmac_write(dmac, USB_DMASWR, 0); usb_dmac_write(dmac, USB_DMAOR, 1); } static void usb_dmac_chan_halt(struct usb_dmac_chan *chan) { u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR); chcr &= ~(USB_DMACHCR_IE | USB_DMACHCR_TE | USB_DMACHCR_DE); usb_dmac_chan_write(chan, USB_DMACHCR, chcr); usb_dmac_soft_reset(chan); } static void usb_dmac_stop(struct usb_dmac *dmac) { usb_dmac_write(dmac, USB_DMAOR, 0); } /* ----------------------------------------------------------------------------- * DMA engine operations */ static int usb_dmac_alloc_chan_resources(struct dma_chan *chan) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); int ret; while (uchan->descs_allocated < USB_DMAC_INITIAL_NR_DESC) { ret = usb_dmac_desc_alloc(uchan, USB_DMAC_INITIAL_NR_SG, GFP_KERNEL); if (ret < 0) { usb_dmac_desc_free(uchan); return ret; } uchan->descs_allocated++; } return pm_runtime_get_sync(chan->device->dev); } static void usb_dmac_free_chan_resources(struct dma_chan *chan) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); unsigned long flags; /* Protect against ISR */ spin_lock_irqsave(&uchan->vc.lock, flags); usb_dmac_chan_halt(uchan); spin_unlock_irqrestore(&uchan->vc.lock, flags); usb_dmac_desc_free(uchan); vchan_free_chan_resources(&uchan->vc); pm_runtime_put(chan->device->dev); } static struct dma_async_tx_descriptor * usb_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction dir, unsigned long dma_flags, void *context) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); struct usb_dmac_desc *desc; struct scatterlist *sg; int i; if (!sg_len) { dev_warn(chan->device->dev, "%s: bad parameter: len=%d\n", __func__, sg_len); return NULL; } desc = usb_dmac_desc_get(uchan, sg_len, GFP_NOWAIT); if (!desc) return NULL; desc->direction = dir; desc->sg_len = sg_len; for_each_sg(sgl, sg, sg_len, i) { desc->sg[i].mem_addr = sg_dma_address(sg); desc->sg[i].size = sg_dma_len(sg); } return vchan_tx_prep(&uchan->vc, &desc->vd, dma_flags); } static int usb_dmac_chan_terminate_all(struct dma_chan *chan) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); struct usb_dmac_desc *desc; unsigned long flags; LIST_HEAD(head); LIST_HEAD(list); spin_lock_irqsave(&uchan->vc.lock, flags); usb_dmac_chan_halt(uchan); vchan_get_all_descriptors(&uchan->vc, &head); if (uchan->desc) uchan->desc = NULL; list_splice_init(&uchan->desc_got, &list); list_for_each_entry(desc, &list, node) list_move_tail(&desc->node, &uchan->desc_freed); spin_unlock_irqrestore(&uchan->vc.lock, flags); vchan_dma_desc_free_list(&uchan->vc, &head); return 0; } static unsigned int usb_dmac_get_current_residue(struct usb_dmac_chan *chan, struct usb_dmac_desc *desc, int sg_index) { struct usb_dmac_sg *sg = desc->sg + sg_index; u32 mem_addr = sg->mem_addr & 0xffffffff; unsigned int residue = sg->size; /* * We cannot use USB_DMATCR to calculate residue because USB_DMATCR * has unsuited value to calculate. */ if (desc->direction == DMA_DEV_TO_MEM) residue -= usb_dmac_chan_read(chan, USB_DMADAR) - mem_addr; else residue -= usb_dmac_chan_read(chan, USB_DMASAR) - mem_addr; return residue; } static u32 usb_dmac_chan_get_residue_if_complete(struct usb_dmac_chan *chan, dma_cookie_t cookie) { struct usb_dmac_desc *desc; u32 residue = 0; list_for_each_entry_reverse(desc, &chan->desc_freed, node) { if (desc->done_cookie == cookie) { residue = desc->residue; break; } } return residue; } static u32 usb_dmac_chan_get_residue(struct usb_dmac_chan *chan, dma_cookie_t cookie) { u32 residue = 0; struct virt_dma_desc *vd; struct usb_dmac_desc *desc = chan->desc; int i; if (!desc) { vd = vchan_find_desc(&chan->vc, cookie); if (!vd) return 0; desc = to_usb_dmac_desc(vd); } /* Compute the size of all usb_dmac_sg still to be transferred */ for (i = desc->sg_index + 1; i < desc->sg_len; i++) residue += desc->sg[i].size; /* Add the residue for the current sg */ residue += usb_dmac_get_current_residue(chan, desc, desc->sg_index); return residue; } static enum dma_status usb_dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); enum dma_status status; unsigned int residue = 0; unsigned long flags; status = dma_cookie_status(chan, cookie, txstate); /* a client driver will get residue after DMA_COMPLETE */ if (!txstate) return status; spin_lock_irqsave(&uchan->vc.lock, flags); if (status == DMA_COMPLETE) residue = usb_dmac_chan_get_residue_if_complete(uchan, cookie); else residue = usb_dmac_chan_get_residue(uchan, cookie); spin_unlock_irqrestore(&uchan->vc.lock, flags); dma_set_residue(txstate, residue); return status; } static void usb_dmac_issue_pending(struct dma_chan *chan) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); unsigned long flags; spin_lock_irqsave(&uchan->vc.lock, flags); if (vchan_issue_pending(&uchan->vc) && !uchan->desc) usb_dmac_chan_start_desc(uchan); spin_unlock_irqrestore(&uchan->vc.lock, flags); } static void usb_dmac_virt_desc_free(struct virt_dma_desc *vd) { struct usb_dmac_desc *desc = to_usb_dmac_desc(vd); struct usb_dmac_chan *chan = to_usb_dmac_chan(vd->tx.chan); usb_dmac_desc_put(chan, desc); } /* ----------------------------------------------------------------------------- * IRQ handling */ static void usb_dmac_isr_transfer_end(struct usb_dmac_chan *chan) { struct usb_dmac_desc *desc = chan->desc; BUG_ON(!desc); if (++desc->sg_index < desc->sg_len) { usb_dmac_chan_start_sg(chan, desc->sg_index); } else { desc->residue = usb_dmac_get_current_residue(chan, desc, desc->sg_index - 1); desc->done_cookie = desc->vd.tx.cookie; vchan_cookie_complete(&desc->vd); /* Restart the next transfer if this driver has a next desc */ usb_dmac_chan_start_desc(chan); } } static irqreturn_t usb_dmac_isr_channel(int irq, void *dev) { struct usb_dmac_chan *chan = dev; irqreturn_t ret = IRQ_NONE; u32 mask = USB_DMACHCR_TE; u32 check_bits = USB_DMACHCR_TE | USB_DMACHCR_SP; u32 chcr; spin_lock(&chan->vc.lock); chcr = usb_dmac_chan_read(chan, USB_DMACHCR); if (chcr & check_bits) mask |= USB_DMACHCR_DE | check_bits; if (chcr & USB_DMACHCR_NULL) { /* An interruption of TE will happen after we set FTE */ mask |= USB_DMACHCR_NULL; chcr |= USB_DMACHCR_FTE; ret |= IRQ_HANDLED; } usb_dmac_chan_write(chan, USB_DMACHCR, chcr & ~mask); if (chcr & check_bits) { usb_dmac_isr_transfer_end(chan); ret |= IRQ_HANDLED; } spin_unlock(&chan->vc.lock); return ret; } /* ----------------------------------------------------------------------------- * OF xlate and channel filter */ static bool usb_dmac_chan_filter(struct dma_chan *chan, void *arg) { struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan); struct of_phandle_args *dma_spec = arg; if (dma_spec->np != chan->device->dev->of_node) return false; /* USB-DMAC should be used with fixed usb controller's FIFO */ if (uchan->index != dma_spec->args[0]) return false; return true; } static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct usb_dmac_chan *uchan; struct dma_chan *chan; dma_cap_mask_t mask; if (dma_spec->args_count != 1) return NULL; /* Only slave DMA channels can be allocated via DT */ dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); chan = dma_request_channel(mask, usb_dmac_chan_filter, dma_spec); if (!chan) return NULL; uchan = to_usb_dmac_chan(chan); return chan; } /* ----------------------------------------------------------------------------- * Power management */ static int usb_dmac_runtime_suspend(struct device *dev) { struct usb_dmac *dmac = dev_get_drvdata(dev); int i; for (i = 0; i < dmac->n_channels; ++i) usb_dmac_chan_halt(&dmac->channels[i]); return 0; } static int usb_dmac_runtime_resume(struct device *dev) { struct usb_dmac *dmac = dev_get_drvdata(dev); return usb_dmac_init(dmac); } static const struct dev_pm_ops usb_dmac_pm = { SET_RUNTIME_PM_OPS(usb_dmac_runtime_suspend, usb_dmac_runtime_resume, NULL) }; /* ----------------------------------------------------------------------------- * Probe and remove */ static int usb_dmac_chan_probe(struct usb_dmac *dmac, struct usb_dmac_chan *uchan, unsigned int index) { struct platform_device *pdev = to_platform_device(dmac->dev); char pdev_irqname[5]; char *irqname; int ret; uchan->index = index; uchan->iomem = dmac->iomem + USB_DMAC_CHAN_OFFSET(index); /* Request the channel interrupt. */ sprintf(pdev_irqname, "ch%u", index); uchan->irq = platform_get_irq_byname(pdev, pdev_irqname); if (uchan->irq < 0) { dev_err(dmac->dev, "no IRQ specified for channel %u\n", index); return -ENODEV; } irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", dev_name(dmac->dev), index); if (!irqname) return -ENOMEM; ret = devm_request_irq(dmac->dev, uchan->irq, usb_dmac_isr_channel, IRQF_SHARED, irqname, uchan); if (ret) { dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", uchan->irq, ret); return ret; } uchan->vc.desc_free = usb_dmac_virt_desc_free; vchan_init(&uchan->vc, &dmac->engine); INIT_LIST_HEAD(&uchan->desc_freed); INIT_LIST_HEAD(&uchan->desc_got); return 0; } static int usb_dmac_parse_of(struct device *dev, struct usb_dmac *dmac) { struct device_node *np = dev->of_node; int ret; ret = of_property_read_u32(np, "dma-channels", &dmac->n_channels); if (ret < 0) { dev_err(dev, "unable to read dma-channels property\n"); return ret; } if (dmac->n_channels <= 0 || dmac->n_channels >= 100) { dev_err(dev, "invalid number of channels %u\n", dmac->n_channels); return -EINVAL; } return 0; } static int usb_dmac_probe(struct platform_device *pdev) { const enum dma_slave_buswidth widths = USB_DMAC_SLAVE_BUSWIDTH; struct dma_device *engine; struct usb_dmac *dmac; struct resource *mem; unsigned int i; int ret; dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL); if (!dmac) return -ENOMEM; dmac->dev = &pdev->dev; platform_set_drvdata(pdev, dmac); ret = usb_dmac_parse_of(&pdev->dev, dmac); if (ret < 0) return ret; dmac->channels = devm_kcalloc(&pdev->dev, dmac->n_channels, sizeof(*dmac->channels), GFP_KERNEL); if (!dmac->channels) return -ENOMEM; /* Request resources. */ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); dmac->iomem = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(dmac->iomem)) return PTR_ERR(dmac->iomem); /* Enable runtime PM and initialize the device. */ pm_runtime_enable(&pdev->dev); ret = pm_runtime_get_sync(&pdev->dev); if (ret < 0) { dev_err(&pdev->dev, "runtime PM get sync failed (%d)\n", ret); return ret; } ret = usb_dmac_init(dmac); pm_runtime_put(&pdev->dev); if (ret) { dev_err(&pdev->dev, "failed to reset device\n"); goto error; } /* Initialize the channels. */ INIT_LIST_HEAD(&dmac->engine.channels); for (i = 0; i < dmac->n_channels; ++i) { ret = usb_dmac_chan_probe(dmac, &dmac->channels[i], i); if (ret < 0) goto error; } /* Register the DMAC as a DMA provider for DT. */ ret = of_dma_controller_register(pdev->dev.of_node, usb_dmac_of_xlate, NULL); if (ret < 0) goto error; /* * Register the DMA engine device. * * Default transfer size of 32 bytes requires 32-byte alignment. */ engine = &dmac->engine; dma_cap_set(DMA_SLAVE, engine->cap_mask); engine->dev = &pdev->dev; engine->src_addr_widths = widths; engine->dst_addr_widths = widths; engine->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM); engine->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; engine->device_alloc_chan_resources = usb_dmac_alloc_chan_resources; engine->device_free_chan_resources = usb_dmac_free_chan_resources; engine->device_prep_slave_sg = usb_dmac_prep_slave_sg; engine->device_terminate_all = usb_dmac_chan_terminate_all; engine->device_tx_status = usb_dmac_tx_status; engine->device_issue_pending = usb_dmac_issue_pending; ret = dma_async_device_register(engine); if (ret < 0) goto error; return 0; error: of_dma_controller_free(pdev->dev.of_node); pm_runtime_disable(&pdev->dev); return ret; } static void usb_dmac_chan_remove(struct usb_dmac *dmac, struct usb_dmac_chan *uchan) { usb_dmac_chan_halt(uchan); devm_free_irq(dmac->dev, uchan->irq, uchan); } static int usb_dmac_remove(struct platform_device *pdev) { struct usb_dmac *dmac = platform_get_drvdata(pdev); int i; for (i = 0; i < dmac->n_channels; ++i) usb_dmac_chan_remove(dmac, &dmac->channels[i]); of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&dmac->engine); pm_runtime_disable(&pdev->dev); return 0; } static void usb_dmac_shutdown(struct platform_device *pdev) { struct usb_dmac *dmac = platform_get_drvdata(pdev); usb_dmac_stop(dmac); } static const struct of_device_id usb_dmac_of_ids[] = { { .compatible = "renesas,usb-dmac", }, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(of, usb_dmac_of_ids); static struct platform_driver usb_dmac_driver = { .driver = { .pm = &usb_dmac_pm, .name = "usb-dmac", .of_match_table = usb_dmac_of_ids, }, .probe = usb_dmac_probe, .remove = usb_dmac_remove, .shutdown = usb_dmac_shutdown, }; module_platform_driver(usb_dmac_driver); MODULE_DESCRIPTION("Renesas USB DMA Controller Driver"); MODULE_AUTHOR("Yoshihiro Shimoda "); MODULE_LICENSE("GPL v2");