![Yoshihiro Shimoda](/assets/img/avatar_default.png)
This patch fixes an issue that the usb_dmac_desc_free() is dereferencing freed memory 'desc' because it uses list_for_each_entry(). This function should use list_for_each_entry_safe(). Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
911 lines
23 KiB
C
911 lines
23 KiB
C
/*
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* Renesas USB DMA Controller Driver
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*
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* Copyright (C) 2015 Renesas Electronics Corporation
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*
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* based on rcar-dmac.c
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* Copyright (C) 2014 Renesas Electronics Inc.
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* Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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*
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* This is free software; you can redistribute it and/or modify
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* it under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*/
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#include <linux/delay.h>
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#include <linux/dma-mapping.h>
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#include <linux/dmaengine.h>
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#include <linux/interrupt.h>
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#include <linux/list.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/of_dma.h>
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#include <linux/of_platform.h>
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#include <linux/platform_device.h>
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#include <linux/pm_runtime.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include "../dmaengine.h"
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#include "../virt-dma.h"
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/*
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* struct usb_dmac_sg - Descriptor for a hardware transfer
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* @mem_addr: memory address
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* @size: transfer size in bytes
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*/
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struct usb_dmac_sg {
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dma_addr_t mem_addr;
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u32 size;
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};
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/*
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* struct usb_dmac_desc - USB DMA Transfer Descriptor
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* @vd: base virtual channel DMA transaction descriptor
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* @direction: direction of the DMA transfer
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* @sg_allocated_len: length of allocated sg
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* @sg_len: length of sg
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* @sg_index: index of sg
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* @residue: residue after the DMAC completed a transfer
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* @node: node for desc_got and desc_freed
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* @done_cookie: cookie after the DMAC completed a transfer
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* @sg: information for the transfer
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*/
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struct usb_dmac_desc {
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struct virt_dma_desc vd;
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enum dma_transfer_direction direction;
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unsigned int sg_allocated_len;
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unsigned int sg_len;
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unsigned int sg_index;
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u32 residue;
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struct list_head node;
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dma_cookie_t done_cookie;
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struct usb_dmac_sg sg[0];
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};
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#define to_usb_dmac_desc(vd) container_of(vd, struct usb_dmac_desc, vd)
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/*
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* struct usb_dmac_chan - USB DMA Controller Channel
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* @vc: base virtual DMA channel object
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* @iomem: channel I/O memory base
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* @index: index of this channel in the controller
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* @irq: irq number of this channel
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* @desc: the current descriptor
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* @descs_allocated: number of descriptors allocated
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* @desc_got: got descriptors
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* @desc_freed: freed descriptors after the DMAC completed a transfer
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*/
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struct usb_dmac_chan {
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struct virt_dma_chan vc;
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void __iomem *iomem;
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unsigned int index;
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int irq;
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struct usb_dmac_desc *desc;
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int descs_allocated;
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struct list_head desc_got;
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struct list_head desc_freed;
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};
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#define to_usb_dmac_chan(c) container_of(c, struct usb_dmac_chan, vc.chan)
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/*
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* struct usb_dmac - USB DMA Controller
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* @engine: base DMA engine object
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* @dev: the hardware device
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* @iomem: remapped I/O memory base
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* @n_channels: number of available channels
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* @channels: array of DMAC channels
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*/
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struct usb_dmac {
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struct dma_device engine;
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struct device *dev;
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void __iomem *iomem;
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unsigned int n_channels;
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struct usb_dmac_chan *channels;
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};
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#define to_usb_dmac(d) container_of(d, struct usb_dmac, engine)
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/* -----------------------------------------------------------------------------
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* Registers
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*/
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#define USB_DMAC_CHAN_OFFSET(i) (0x20 + 0x20 * (i))
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#define USB_DMASWR 0x0008
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#define USB_DMASWR_SWR (1 << 0)
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#define USB_DMAOR 0x0060
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#define USB_DMAOR_AE (1 << 2)
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#define USB_DMAOR_DME (1 << 0)
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#define USB_DMASAR 0x0000
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#define USB_DMADAR 0x0004
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#define USB_DMATCR 0x0008
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#define USB_DMATCR_MASK 0x00ffffff
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#define USB_DMACHCR 0x0014
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#define USB_DMACHCR_FTE (1 << 24)
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#define USB_DMACHCR_NULLE (1 << 16)
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#define USB_DMACHCR_NULL (1 << 12)
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#define USB_DMACHCR_TS_8B ((0 << 7) | (0 << 6))
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#define USB_DMACHCR_TS_16B ((0 << 7) | (1 << 6))
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#define USB_DMACHCR_TS_32B ((1 << 7) | (0 << 6))
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#define USB_DMACHCR_IE (1 << 5)
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#define USB_DMACHCR_SP (1 << 2)
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#define USB_DMACHCR_TE (1 << 1)
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#define USB_DMACHCR_DE (1 << 0)
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#define USB_DMATEND 0x0018
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/* Hardcode the xfer_shift to 5 (32bytes) */
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#define USB_DMAC_XFER_SHIFT 5
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#define USB_DMAC_XFER_SIZE (1 << USB_DMAC_XFER_SHIFT)
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#define USB_DMAC_CHCR_TS USB_DMACHCR_TS_32B
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#define USB_DMAC_SLAVE_BUSWIDTH DMA_SLAVE_BUSWIDTH_32_BYTES
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/* for descriptors */
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#define USB_DMAC_INITIAL_NR_DESC 16
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#define USB_DMAC_INITIAL_NR_SG 8
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/* -----------------------------------------------------------------------------
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* Device access
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*/
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static void usb_dmac_write(struct usb_dmac *dmac, u32 reg, u32 data)
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{
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writel(data, dmac->iomem + reg);
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}
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static u32 usb_dmac_read(struct usb_dmac *dmac, u32 reg)
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{
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return readl(dmac->iomem + reg);
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}
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static u32 usb_dmac_chan_read(struct usb_dmac_chan *chan, u32 reg)
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{
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return readl(chan->iomem + reg);
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}
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static void usb_dmac_chan_write(struct usb_dmac_chan *chan, u32 reg, u32 data)
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{
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writel(data, chan->iomem + reg);
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}
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/* -----------------------------------------------------------------------------
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* Initialization and configuration
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*/
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static bool usb_dmac_chan_is_busy(struct usb_dmac_chan *chan)
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{
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u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR);
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return (chcr & (USB_DMACHCR_DE | USB_DMACHCR_TE)) == USB_DMACHCR_DE;
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}
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static u32 usb_dmac_calc_tend(u32 size)
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{
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/*
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* Please refer to the Figure "Example of Final Transaction Valid
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* Data Transfer Enable (EDTEN) Setting" in the data sheet.
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*/
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return 0xffffffff << (32 - (size % USB_DMAC_XFER_SIZE ? :
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USB_DMAC_XFER_SIZE));
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}
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/* This function is already held by vc.lock */
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static void usb_dmac_chan_start_sg(struct usb_dmac_chan *chan,
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unsigned int index)
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{
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struct usb_dmac_desc *desc = chan->desc;
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struct usb_dmac_sg *sg = desc->sg + index;
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dma_addr_t src_addr = 0, dst_addr = 0;
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WARN_ON_ONCE(usb_dmac_chan_is_busy(chan));
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if (desc->direction == DMA_DEV_TO_MEM)
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dst_addr = sg->mem_addr;
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else
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src_addr = sg->mem_addr;
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dev_dbg(chan->vc.chan.device->dev,
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"chan%u: queue sg %p: %u@%pad -> %pad\n",
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chan->index, sg, sg->size, &src_addr, &dst_addr);
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usb_dmac_chan_write(chan, USB_DMASAR, src_addr & 0xffffffff);
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usb_dmac_chan_write(chan, USB_DMADAR, dst_addr & 0xffffffff);
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usb_dmac_chan_write(chan, USB_DMATCR,
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DIV_ROUND_UP(sg->size, USB_DMAC_XFER_SIZE));
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usb_dmac_chan_write(chan, USB_DMATEND, usb_dmac_calc_tend(sg->size));
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usb_dmac_chan_write(chan, USB_DMACHCR, USB_DMAC_CHCR_TS |
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USB_DMACHCR_NULLE | USB_DMACHCR_IE | USB_DMACHCR_DE);
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}
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/* This function is already held by vc.lock */
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static void usb_dmac_chan_start_desc(struct usb_dmac_chan *chan)
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{
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struct virt_dma_desc *vd;
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vd = vchan_next_desc(&chan->vc);
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if (!vd) {
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chan->desc = NULL;
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return;
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}
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/*
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* Remove this request from vc->desc_issued. Otherwise, this driver
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* will get the previous value from vchan_next_desc() after a transfer
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* was completed.
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*/
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list_del(&vd->node);
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chan->desc = to_usb_dmac_desc(vd);
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chan->desc->sg_index = 0;
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usb_dmac_chan_start_sg(chan, 0);
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}
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static int usb_dmac_init(struct usb_dmac *dmac)
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{
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u16 dmaor;
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/* Clear all channels and enable the DMAC globally. */
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usb_dmac_write(dmac, USB_DMAOR, USB_DMAOR_DME);
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dmaor = usb_dmac_read(dmac, USB_DMAOR);
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if ((dmaor & (USB_DMAOR_AE | USB_DMAOR_DME)) != USB_DMAOR_DME) {
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dev_warn(dmac->dev, "DMAOR initialization failed.\n");
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return -EIO;
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}
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return 0;
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}
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/* -----------------------------------------------------------------------------
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* Descriptors allocation and free
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*/
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static int usb_dmac_desc_alloc(struct usb_dmac_chan *chan, unsigned int sg_len,
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gfp_t gfp)
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{
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struct usb_dmac_desc *desc;
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unsigned long flags;
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desc = kzalloc(sizeof(*desc) + sg_len * sizeof(desc->sg[0]), gfp);
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if (!desc)
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return -ENOMEM;
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desc->sg_allocated_len = sg_len;
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INIT_LIST_HEAD(&desc->node);
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spin_lock_irqsave(&chan->vc.lock, flags);
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list_add_tail(&desc->node, &chan->desc_freed);
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spin_unlock_irqrestore(&chan->vc.lock, flags);
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return 0;
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}
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static void usb_dmac_desc_free(struct usb_dmac_chan *chan)
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{
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struct usb_dmac_desc *desc, *_desc;
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LIST_HEAD(list);
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list_splice_init(&chan->desc_freed, &list);
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list_splice_init(&chan->desc_got, &list);
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list_for_each_entry_safe(desc, _desc, &list, node) {
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list_del(&desc->node);
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kfree(desc);
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}
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chan->descs_allocated = 0;
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}
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static struct usb_dmac_desc *usb_dmac_desc_get(struct usb_dmac_chan *chan,
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unsigned int sg_len, gfp_t gfp)
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{
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struct usb_dmac_desc *desc = NULL;
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unsigned long flags;
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/* Get a freed descritpor */
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spin_lock_irqsave(&chan->vc.lock, flags);
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list_for_each_entry(desc, &chan->desc_freed, node) {
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if (sg_len <= desc->sg_allocated_len) {
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list_move_tail(&desc->node, &chan->desc_got);
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spin_unlock_irqrestore(&chan->vc.lock, flags);
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return desc;
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}
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}
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spin_unlock_irqrestore(&chan->vc.lock, flags);
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/* Allocate a new descriptor */
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if (!usb_dmac_desc_alloc(chan, sg_len, gfp)) {
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/* If allocated the desc, it was added to tail of the list */
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spin_lock_irqsave(&chan->vc.lock, flags);
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desc = list_last_entry(&chan->desc_freed, struct usb_dmac_desc,
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node);
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list_move_tail(&desc->node, &chan->desc_got);
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spin_unlock_irqrestore(&chan->vc.lock, flags);
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return desc;
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}
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return NULL;
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}
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static void usb_dmac_desc_put(struct usb_dmac_chan *chan,
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struct usb_dmac_desc *desc)
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{
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unsigned long flags;
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spin_lock_irqsave(&chan->vc.lock, flags);
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list_move_tail(&desc->node, &chan->desc_freed);
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spin_unlock_irqrestore(&chan->vc.lock, flags);
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}
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/* -----------------------------------------------------------------------------
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* Stop and reset
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*/
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static void usb_dmac_soft_reset(struct usb_dmac_chan *uchan)
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{
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struct dma_chan *chan = &uchan->vc.chan;
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struct usb_dmac *dmac = to_usb_dmac(chan->device);
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int i;
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/* Don't issue soft reset if any one of channels is busy */
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for (i = 0; i < dmac->n_channels; ++i) {
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if (usb_dmac_chan_is_busy(uchan))
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return;
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}
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usb_dmac_write(dmac, USB_DMAOR, 0);
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usb_dmac_write(dmac, USB_DMASWR, USB_DMASWR_SWR);
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udelay(100);
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usb_dmac_write(dmac, USB_DMASWR, 0);
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usb_dmac_write(dmac, USB_DMAOR, 1);
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}
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static void usb_dmac_chan_halt(struct usb_dmac_chan *chan)
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{
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u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR);
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chcr &= ~(USB_DMACHCR_IE | USB_DMACHCR_TE | USB_DMACHCR_DE);
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usb_dmac_chan_write(chan, USB_DMACHCR, chcr);
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usb_dmac_soft_reset(chan);
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}
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static void usb_dmac_stop(struct usb_dmac *dmac)
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{
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usb_dmac_write(dmac, USB_DMAOR, 0);
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}
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/* -----------------------------------------------------------------------------
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* DMA engine operations
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*/
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static int usb_dmac_alloc_chan_resources(struct dma_chan *chan)
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{
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struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
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int ret;
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while (uchan->descs_allocated < USB_DMAC_INITIAL_NR_DESC) {
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ret = usb_dmac_desc_alloc(uchan, USB_DMAC_INITIAL_NR_SG,
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GFP_KERNEL);
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if (ret < 0) {
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usb_dmac_desc_free(uchan);
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return ret;
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}
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uchan->descs_allocated++;
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}
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return pm_runtime_get_sync(chan->device->dev);
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}
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static void usb_dmac_free_chan_resources(struct dma_chan *chan)
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{
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struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
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unsigned long flags;
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/* Protect against ISR */
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spin_lock_irqsave(&uchan->vc.lock, flags);
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usb_dmac_chan_halt(uchan);
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spin_unlock_irqrestore(&uchan->vc.lock, flags);
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usb_dmac_desc_free(uchan);
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vchan_free_chan_resources(&uchan->vc);
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pm_runtime_put(chan->device->dev);
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}
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static struct dma_async_tx_descriptor *
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usb_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
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unsigned int sg_len, enum dma_transfer_direction dir,
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unsigned long dma_flags, void *context)
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{
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struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
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struct usb_dmac_desc *desc;
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struct scatterlist *sg;
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int i;
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if (!sg_len) {
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dev_warn(chan->device->dev,
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"%s: bad parameter: len=%d\n", __func__, sg_len);
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return NULL;
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}
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desc = usb_dmac_desc_get(uchan, sg_len, GFP_NOWAIT);
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if (!desc)
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return NULL;
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desc->direction = dir;
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desc->sg_len = sg_len;
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for_each_sg(sgl, sg, sg_len, i) {
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desc->sg[i].mem_addr = sg_dma_address(sg);
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desc->sg[i].size = sg_dma_len(sg);
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}
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return vchan_tx_prep(&uchan->vc, &desc->vd, dma_flags);
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}
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static int usb_dmac_chan_terminate_all(struct dma_chan *chan)
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{
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struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
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struct usb_dmac_desc *desc;
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unsigned long flags;
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LIST_HEAD(head);
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LIST_HEAD(list);
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spin_lock_irqsave(&uchan->vc.lock, flags);
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usb_dmac_chan_halt(uchan);
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vchan_get_all_descriptors(&uchan->vc, &head);
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if (uchan->desc)
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uchan->desc = NULL;
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list_splice_init(&uchan->desc_got, &list);
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list_for_each_entry(desc, &list, node)
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list_move_tail(&desc->node, &uchan->desc_freed);
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spin_unlock_irqrestore(&uchan->vc.lock, flags);
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vchan_dma_desc_free_list(&uchan->vc, &head);
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return 0;
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}
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static unsigned int usb_dmac_get_current_residue(struct usb_dmac_chan *chan,
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struct usb_dmac_desc *desc,
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int sg_index)
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{
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struct usb_dmac_sg *sg = desc->sg + sg_index;
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u32 mem_addr = sg->mem_addr & 0xffffffff;
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unsigned int residue = sg->size;
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/*
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* We cannot use USB_DMATCR to calculate residue because USB_DMATCR
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* has unsuited value to calculate.
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*/
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if (desc->direction == DMA_DEV_TO_MEM)
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residue -= usb_dmac_chan_read(chan, USB_DMADAR) - mem_addr;
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else
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residue -= usb_dmac_chan_read(chan, USB_DMASAR) - mem_addr;
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|
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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 <yoshihiro.shimoda.uh@renesas.com>");
|
|
MODULE_LICENSE("GPL v2");
|