xref: /openbmc/linux/sound/pci/asihpi/hpios.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 
4     AudioScience HPI driver
5     Copyright (C) 1997-2012  AudioScience Inc. <support@audioscience.com>
6 
7 
8 HPI Operating System function implementation for Linux
9 
10 (C) Copyright AudioScience Inc. 1997-2003
11 ******************************************************************************/
12 #define SOURCEFILE_NAME "hpios.c"
13 #include "hpi_internal.h"
14 #include "hpidebug.h"
15 #include <linux/delay.h>
16 #include <linux/sched.h>
17 
18 void hpios_delay_micro_seconds(u32 num_micro_sec)
19 {
20 	if ((usecs_to_jiffies(num_micro_sec) > 1) && !in_interrupt()) {
21 		/* MUST NOT SCHEDULE IN INTERRUPT CONTEXT! */
22 		schedule_timeout_uninterruptible(usecs_to_jiffies
23 			(num_micro_sec));
24 	} else if (num_micro_sec <= 2000)
25 		udelay(num_micro_sec);
26 	else
27 		mdelay(num_micro_sec / 1000);
28 
29 }
30 
31 /** Allocate an area of locked memory for bus master DMA operations.
32 
33 If allocation fails, return 1, and *pMemArea.size = 0
34 */
35 u16 hpios_locked_mem_alloc(struct consistent_dma_area *p_mem_area, u32 size,
36 	struct pci_dev *pdev)
37 {
38 	/*?? any benefit in using managed dmam_alloc_coherent? */
39 	p_mem_area->vaddr =
40 		dma_alloc_coherent(&pdev->dev, size, &p_mem_area->dma_handle,
41 		GFP_KERNEL);
42 
43 	if (p_mem_area->vaddr) {
44 		HPI_DEBUG_LOG(DEBUG, "allocated %d bytes, dma 0x%x vma %p\n",
45 			size, (unsigned int)p_mem_area->dma_handle,
46 			p_mem_area->vaddr);
47 		p_mem_area->pdev = &pdev->dev;
48 		p_mem_area->size = size;
49 		return 0;
50 	} else {
51 		HPI_DEBUG_LOG(WARNING,
52 			"failed to allocate %d bytes locked memory\n", size);
53 		p_mem_area->size = 0;
54 		return 1;
55 	}
56 }
57 
58 u16 hpios_locked_mem_free(struct consistent_dma_area *p_mem_area)
59 {
60 	if (p_mem_area->size) {
61 		dma_free_coherent(p_mem_area->pdev, p_mem_area->size,
62 			p_mem_area->vaddr, p_mem_area->dma_handle);
63 		HPI_DEBUG_LOG(DEBUG, "freed %lu bytes, dma 0x%x vma %p\n",
64 			(unsigned long)p_mem_area->size,
65 			(unsigned int)p_mem_area->dma_handle,
66 			p_mem_area->vaddr);
67 		p_mem_area->size = 0;
68 		return 0;
69 	} else {
70 		return 1;
71 	}
72 }
73