// SPDX-License-Identifier: GPL-2.0 /* * 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 <[email protected]> */ #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/dmaengine.h> #include <linux/interrupt.h> #include <linux/list.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_dma.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/slab.h> #include <linux/spinlock.h> #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 { … }; /* * 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 { … }; #define to_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 { … }; #define to_usb_dmac_chan(c) … /* * 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 { … }; #define to_usb_dmac(d) … /* ----------------------------------------------------------------------------- * Registers */ #define USB_DMAC_CHAN_OFFSET(i) … #define USB_DMASWR … #define USB_DMASWR_SWR … #define USB_DMAOR … #define USB_DMAOR_AE … #define USB_DMAOR_DME … #define USB_DMASAR … #define USB_DMADAR … #define USB_DMATCR … #define USB_DMATCR_MASK … #define USB_DMACHCR … #define USB_DMACHCR_FTE … #define USB_DMACHCR_NULLE … #define USB_DMACHCR_NULL … #define USB_DMACHCR_TS_8B … #define USB_DMACHCR_TS_16B … #define USB_DMACHCR_TS_32B … #define USB_DMACHCR_IE … #define USB_DMACHCR_SP … #define USB_DMACHCR_TE … #define USB_DMACHCR_DE … #define USB_DMATEND … /* Hardcode the xfer_shift to 5 (32bytes) */ #define USB_DMAC_XFER_SHIFT … #define USB_DMAC_XFER_SIZE … #define USB_DMAC_CHCR_TS … #define USB_DMAC_SLAVE_BUSWIDTH … /* for descriptors */ #define USB_DMAC_INITIAL_NR_DESC … #define USB_DMAC_INITIAL_NR_SG … /* ----------------------------------------------------------------------------- * Device access */ static void usb_dmac_write(struct usb_dmac *dmac, u32 reg, u32 data) { … } static u32 usb_dmac_read(struct usb_dmac *dmac, u32 reg) { … } static u32 usb_dmac_chan_read(struct usb_dmac_chan *chan, u32 reg) { … } static void usb_dmac_chan_write(struct usb_dmac_chan *chan, u32 reg, u32 data) { … } /* ----------------------------------------------------------------------------- * Initialization and configuration */ static bool usb_dmac_chan_is_busy(struct usb_dmac_chan *chan) { … } static u32 usb_dmac_calc_tend(u32 size) { … } /* This function is already held by vc.lock */ static void usb_dmac_chan_start_sg(struct usb_dmac_chan *chan, unsigned int index) { … } /* This function is already held by vc.lock */ static void usb_dmac_chan_start_desc(struct usb_dmac_chan *chan) { … } static int usb_dmac_init(struct usb_dmac *dmac) { … } /* ----------------------------------------------------------------------------- * Descriptors allocation and free */ static int usb_dmac_desc_alloc(struct usb_dmac_chan *chan, unsigned int sg_len, gfp_t gfp) { … } static void usb_dmac_desc_free(struct usb_dmac_chan *chan) { … } static struct usb_dmac_desc *usb_dmac_desc_get(struct usb_dmac_chan *chan, unsigned int sg_len, gfp_t gfp) { … } static void usb_dmac_desc_put(struct usb_dmac_chan *chan, struct usb_dmac_desc *desc) { … } /* ----------------------------------------------------------------------------- * Stop and reset */ static void usb_dmac_soft_reset(struct usb_dmac_chan *uchan) { … } static void usb_dmac_chan_halt(struct usb_dmac_chan *chan) { … } static void usb_dmac_stop(struct usb_dmac *dmac) { … } /* ----------------------------------------------------------------------------- * DMA engine operations */ static int usb_dmac_alloc_chan_resources(struct dma_chan *chan) { … } static void usb_dmac_free_chan_resources(struct dma_chan *chan) { … } 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) { … } static int usb_dmac_chan_terminate_all(struct dma_chan *chan) { … } static unsigned int usb_dmac_get_current_residue(struct usb_dmac_chan *chan, struct usb_dmac_desc *desc, unsigned int sg_index) { … } static u32 usb_dmac_chan_get_residue_if_complete(struct usb_dmac_chan *chan, dma_cookie_t cookie) { … } static u32 usb_dmac_chan_get_residue(struct usb_dmac_chan *chan, dma_cookie_t cookie) { … } static enum dma_status usb_dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { … } static void usb_dmac_issue_pending(struct dma_chan *chan) { … } static void usb_dmac_virt_desc_free(struct virt_dma_desc *vd) { … } /* ----------------------------------------------------------------------------- * IRQ handling */ static void usb_dmac_isr_transfer_end(struct usb_dmac_chan *chan) { … } static irqreturn_t usb_dmac_isr_channel(int irq, void *dev) { … } /* ----------------------------------------------------------------------------- * OF xlate and channel filter */ static bool usb_dmac_chan_filter(struct dma_chan *chan, void *arg) { … } static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { … } /* ----------------------------------------------------------------------------- * Power management */ #ifdef CONFIG_PM static int usb_dmac_runtime_suspend(struct device *dev) { … } static int usb_dmac_runtime_resume(struct device *dev) { … } #endif /* CONFIG_PM */ static const struct dev_pm_ops usb_dmac_pm = …; /* ----------------------------------------------------------------------------- * Probe and remove */ static int usb_dmac_chan_probe(struct usb_dmac *dmac, struct usb_dmac_chan *uchan, u8 index) { … } static int usb_dmac_parse_of(struct device *dev, struct usb_dmac *dmac) { … } static int usb_dmac_probe(struct platform_device *pdev) { … } static void usb_dmac_chan_remove(struct usb_dmac *dmac, struct usb_dmac_chan *uchan) { … } static void usb_dmac_remove(struct platform_device *pdev) { … } static void usb_dmac_shutdown(struct platform_device *pdev) { … } static const struct of_device_id usb_dmac_of_ids[] = …; MODULE_DEVICE_TABLE(of, usb_dmac_of_ids); static struct platform_driver usb_dmac_driver = …; module_platform_driver(…) …; MODULE_DESCRIPTION(…) …; MODULE_AUTHOR(…) …; MODULE_LICENSE(…) …;
Codebase Browser
linux