1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * Copyright 2013-2015 Analog Devices Inc. 4*4882a593Smuzhiyun * Author: Lars-Peter Clausen <lars@metafoo.de> 5*4882a593Smuzhiyun */ 6*4882a593Smuzhiyun 7*4882a593Smuzhiyun #ifndef __INDUSTRIALIO_DMA_BUFFER_H__ 8*4882a593Smuzhiyun #define __INDUSTRIALIO_DMA_BUFFER_H__ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #include <linux/list.h> 11*4882a593Smuzhiyun #include <linux/kref.h> 12*4882a593Smuzhiyun #include <linux/spinlock.h> 13*4882a593Smuzhiyun #include <linux/mutex.h> 14*4882a593Smuzhiyun #include <linux/iio/buffer_impl.h> 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun struct iio_dma_buffer_queue; 17*4882a593Smuzhiyun struct iio_dma_buffer_ops; 18*4882a593Smuzhiyun struct device; 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun struct iio_buffer_block { 21*4882a593Smuzhiyun u32 size; 22*4882a593Smuzhiyun u32 bytes_used; 23*4882a593Smuzhiyun }; 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun /** 26*4882a593Smuzhiyun * enum iio_block_state - State of a struct iio_dma_buffer_block 27*4882a593Smuzhiyun * @IIO_BLOCK_STATE_DEQUEUED: Block is not queued 28*4882a593Smuzhiyun * @IIO_BLOCK_STATE_QUEUED: Block is on the incoming queue 29*4882a593Smuzhiyun * @IIO_BLOCK_STATE_ACTIVE: Block is currently being processed by the DMA 30*4882a593Smuzhiyun * @IIO_BLOCK_STATE_DONE: Block is on the outgoing queue 31*4882a593Smuzhiyun * @IIO_BLOCK_STATE_DEAD: Block has been marked as to be freed 32*4882a593Smuzhiyun */ 33*4882a593Smuzhiyun enum iio_block_state { 34*4882a593Smuzhiyun IIO_BLOCK_STATE_DEQUEUED, 35*4882a593Smuzhiyun IIO_BLOCK_STATE_QUEUED, 36*4882a593Smuzhiyun IIO_BLOCK_STATE_ACTIVE, 37*4882a593Smuzhiyun IIO_BLOCK_STATE_DONE, 38*4882a593Smuzhiyun IIO_BLOCK_STATE_DEAD, 39*4882a593Smuzhiyun }; 40*4882a593Smuzhiyun 41*4882a593Smuzhiyun /** 42*4882a593Smuzhiyun * struct iio_dma_buffer_block - IIO buffer block 43*4882a593Smuzhiyun * @head: List head 44*4882a593Smuzhiyun * @size: Total size of the block in bytes 45*4882a593Smuzhiyun * @bytes_used: Number of bytes that contain valid data 46*4882a593Smuzhiyun * @vaddr: Virutal address of the blocks memory 47*4882a593Smuzhiyun * @phys_addr: Physical address of the blocks memory 48*4882a593Smuzhiyun * @queue: Parent DMA buffer queue 49*4882a593Smuzhiyun * @kref: kref used to manage the lifetime of block 50*4882a593Smuzhiyun * @state: Current state of the block 51*4882a593Smuzhiyun */ 52*4882a593Smuzhiyun struct iio_dma_buffer_block { 53*4882a593Smuzhiyun /* May only be accessed by the owner of the block */ 54*4882a593Smuzhiyun struct list_head head; 55*4882a593Smuzhiyun size_t bytes_used; 56*4882a593Smuzhiyun 57*4882a593Smuzhiyun /* 58*4882a593Smuzhiyun * Set during allocation, constant thereafter. May be accessed read-only 59*4882a593Smuzhiyun * by anybody holding a reference to the block. 60*4882a593Smuzhiyun */ 61*4882a593Smuzhiyun void *vaddr; 62*4882a593Smuzhiyun dma_addr_t phys_addr; 63*4882a593Smuzhiyun size_t size; 64*4882a593Smuzhiyun struct iio_dma_buffer_queue *queue; 65*4882a593Smuzhiyun 66*4882a593Smuzhiyun /* Must not be accessed outside the core. */ 67*4882a593Smuzhiyun struct kref kref; 68*4882a593Smuzhiyun /* 69*4882a593Smuzhiyun * Must not be accessed outside the core. Access needs to hold 70*4882a593Smuzhiyun * queue->list_lock if the block is not owned by the core. 71*4882a593Smuzhiyun */ 72*4882a593Smuzhiyun enum iio_block_state state; 73*4882a593Smuzhiyun }; 74*4882a593Smuzhiyun 75*4882a593Smuzhiyun /** 76*4882a593Smuzhiyun * struct iio_dma_buffer_queue_fileio - FileIO state for the DMA buffer 77*4882a593Smuzhiyun * @blocks: Buffer blocks used for fileio 78*4882a593Smuzhiyun * @active_block: Block being used in read() 79*4882a593Smuzhiyun * @pos: Read offset in the active block 80*4882a593Smuzhiyun * @block_size: Size of each block 81*4882a593Smuzhiyun */ 82*4882a593Smuzhiyun struct iio_dma_buffer_queue_fileio { 83*4882a593Smuzhiyun struct iio_dma_buffer_block *blocks[2]; 84*4882a593Smuzhiyun struct iio_dma_buffer_block *active_block; 85*4882a593Smuzhiyun size_t pos; 86*4882a593Smuzhiyun size_t block_size; 87*4882a593Smuzhiyun }; 88*4882a593Smuzhiyun 89*4882a593Smuzhiyun /** 90*4882a593Smuzhiyun * struct iio_dma_buffer_queue - DMA buffer base structure 91*4882a593Smuzhiyun * @buffer: IIO buffer base structure 92*4882a593Smuzhiyun * @dev: Parent device 93*4882a593Smuzhiyun * @ops: DMA buffer callbacks 94*4882a593Smuzhiyun * @lock: Protects the incoming list, active and the fields in the fileio 95*4882a593Smuzhiyun * substruct 96*4882a593Smuzhiyun * @list_lock: Protects lists that contain blocks which can be modified in 97*4882a593Smuzhiyun * atomic context as well as blocks on those lists. This is the outgoing queue 98*4882a593Smuzhiyun * list and typically also a list of active blocks in the part that handles 99*4882a593Smuzhiyun * the DMA controller 100*4882a593Smuzhiyun * @incoming: List of buffers on the incoming queue 101*4882a593Smuzhiyun * @outgoing: List of buffers on the outgoing queue 102*4882a593Smuzhiyun * @active: Whether the buffer is currently active 103*4882a593Smuzhiyun * @fileio: FileIO state 104*4882a593Smuzhiyun */ 105*4882a593Smuzhiyun struct iio_dma_buffer_queue { 106*4882a593Smuzhiyun struct iio_buffer buffer; 107*4882a593Smuzhiyun struct device *dev; 108*4882a593Smuzhiyun const struct iio_dma_buffer_ops *ops; 109*4882a593Smuzhiyun 110*4882a593Smuzhiyun struct mutex lock; 111*4882a593Smuzhiyun spinlock_t list_lock; 112*4882a593Smuzhiyun struct list_head incoming; 113*4882a593Smuzhiyun struct list_head outgoing; 114*4882a593Smuzhiyun 115*4882a593Smuzhiyun bool active; 116*4882a593Smuzhiyun 117*4882a593Smuzhiyun struct iio_dma_buffer_queue_fileio fileio; 118*4882a593Smuzhiyun }; 119*4882a593Smuzhiyun 120*4882a593Smuzhiyun /** 121*4882a593Smuzhiyun * struct iio_dma_buffer_ops - DMA buffer callback operations 122*4882a593Smuzhiyun * @submit: Called when a block is submitted to the DMA controller 123*4882a593Smuzhiyun * @abort: Should abort all pending transfers 124*4882a593Smuzhiyun */ 125*4882a593Smuzhiyun struct iio_dma_buffer_ops { 126*4882a593Smuzhiyun int (*submit)(struct iio_dma_buffer_queue *queue, 127*4882a593Smuzhiyun struct iio_dma_buffer_block *block); 128*4882a593Smuzhiyun void (*abort)(struct iio_dma_buffer_queue *queue); 129*4882a593Smuzhiyun }; 130*4882a593Smuzhiyun 131*4882a593Smuzhiyun void iio_dma_buffer_block_done(struct iio_dma_buffer_block *block); 132*4882a593Smuzhiyun void iio_dma_buffer_block_list_abort(struct iio_dma_buffer_queue *queue, 133*4882a593Smuzhiyun struct list_head *list); 134*4882a593Smuzhiyun 135*4882a593Smuzhiyun int iio_dma_buffer_enable(struct iio_buffer *buffer, 136*4882a593Smuzhiyun struct iio_dev *indio_dev); 137*4882a593Smuzhiyun int iio_dma_buffer_disable(struct iio_buffer *buffer, 138*4882a593Smuzhiyun struct iio_dev *indio_dev); 139*4882a593Smuzhiyun int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n, 140*4882a593Smuzhiyun char __user *user_buffer); 141*4882a593Smuzhiyun size_t iio_dma_buffer_data_available(struct iio_buffer *buffer); 142*4882a593Smuzhiyun int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd); 143*4882a593Smuzhiyun int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length); 144*4882a593Smuzhiyun int iio_dma_buffer_request_update(struct iio_buffer *buffer); 145*4882a593Smuzhiyun 146*4882a593Smuzhiyun int iio_dma_buffer_init(struct iio_dma_buffer_queue *queue, 147*4882a593Smuzhiyun struct device *dma_dev, const struct iio_dma_buffer_ops *ops); 148*4882a593Smuzhiyun void iio_dma_buffer_exit(struct iio_dma_buffer_queue *queue); 149*4882a593Smuzhiyun void iio_dma_buffer_release(struct iio_dma_buffer_queue *queue); 150*4882a593Smuzhiyun 151*4882a593Smuzhiyun #endif 152