1/*
2 * PCI driver for the High Speed UART DMA
3 *
4 * Copyright (C) 2015 Intel Corporation
5 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
6 *
7 * Partially based on the bits found in drivers/tty/serial/mfd.c.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/bitops.h>
15#include <linux/device.h>
16#include <linux/module.h>
17#include <linux/pci.h>
18
19#include "hsu.h"
20
21#define HSU_PCI_DMASR		0x00
22#define HSU_PCI_DMAISR		0x04
23
24#define HSU_PCI_CHAN_OFFSET	0x100
25
26static irqreturn_t hsu_pci_irq(int irq, void *dev)
27{
28	struct hsu_dma_chip *chip = dev;
29	u32 dmaisr;
30	unsigned short i;
31	irqreturn_t ret = IRQ_NONE;
32
33	dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
34	for (i = 0; i < chip->pdata->nr_channels; i++) {
35		if (dmaisr & 0x1)
36			ret |= hsu_dma_irq(chip, i);
37		dmaisr >>= 1;
38	}
39
40	return ret;
41}
42
43static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
44{
45	struct hsu_dma_chip *chip;
46	int ret;
47
48	ret = pcim_enable_device(pdev);
49	if (ret)
50		return ret;
51
52	ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
53	if (ret) {
54		dev_err(&pdev->dev, "I/O memory remapping failed\n");
55		return ret;
56	}
57
58	pci_set_master(pdev);
59	pci_try_set_mwi(pdev);
60
61	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
62	if (ret)
63		return ret;
64
65	ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
66	if (ret)
67		return ret;
68
69	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
70	if (!chip)
71		return -ENOMEM;
72
73	chip->dev = &pdev->dev;
74	chip->regs = pcim_iomap_table(pdev)[0];
75	chip->length = pci_resource_len(pdev, 0);
76	chip->offset = HSU_PCI_CHAN_OFFSET;
77	chip->irq = pdev->irq;
78
79	pci_enable_msi(pdev);
80
81	ret = hsu_dma_probe(chip);
82	if (ret)
83		return ret;
84
85	ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
86	if (ret)
87		goto err_register_irq;
88
89	pci_set_drvdata(pdev, chip);
90
91	return 0;
92
93err_register_irq:
94	hsu_dma_remove(chip);
95	return ret;
96}
97
98static void hsu_pci_remove(struct pci_dev *pdev)
99{
100	struct hsu_dma_chip *chip = pci_get_drvdata(pdev);
101
102	free_irq(chip->irq, chip);
103	hsu_dma_remove(chip);
104}
105
106static const struct pci_device_id hsu_pci_id_table[] = {
107	{ PCI_VDEVICE(INTEL, 0x081e), 0 },
108	{ PCI_VDEVICE(INTEL, 0x1192), 0 },
109	{ }
110};
111MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
112
113static struct pci_driver hsu_pci_driver = {
114	.name		= "hsu_dma_pci",
115	.id_table	= hsu_pci_id_table,
116	.probe		= hsu_pci_probe,
117	.remove		= hsu_pci_remove,
118};
119
120module_pci_driver(hsu_pci_driver);
121
122MODULE_LICENSE("GPL v2");
123MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
124MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
125