spi-amd-pci.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * AMD SPI controller driver
 4 *
 5 * Copyright (c) 2025, Advanced Micro Devices, Inc.
 6 * All Rights Reserved.
 7 *
 8 * Authors: Krishnamoorthi M <krishnamoorthi.m@amd.com>
 9 *          Akshata MukundShetty <akshata.mukundshetty@amd.com>
10 */
11
12#include <linux/init.h>
13#include <linux/spi/spi.h>
14#include <linux/pci.h>
15
16#include "spi-amd.h"
17
18#define AMD_PCI_DEVICE_ID_LPC_BRIDGE		0x1682
19#define AMD_PCI_LPC_SPI_BASE_ADDR_REG		0xA0
20#define AMD_SPI_BASE_ADDR_MASK			~0xFF
21#define AMD_HID2_PCI_BAR_OFFSET			0x00002000
22#define AMD_HID2_MEM_SIZE			0x200
23
24static struct pci_device_id pci_spi_ids[] = {
25	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_PCI_DEVICE_ID_LPC_BRIDGE) },
26	{ 0, }
27};
28MODULE_DEVICE_TABLE(pci, pci_spi_ids);
29
30static int amd_spi_pci_probe(struct pci_dev *pdev,
31			     const struct pci_device_id *id)
32{
33	struct device *dev = &pdev->dev;
34	struct spi_controller *host;
35	struct amd_spi *amd_spi;
36	u32 io_base_addr;
37
38	/* Allocate storage for host and driver private data */
39	host = devm_spi_alloc_host(dev, sizeof(struct amd_spi));
40	if (!host)
41		return -ENOMEM;
42
43	amd_spi = spi_controller_get_devdata(host);
44
45	pci_read_config_dword(pdev, AMD_PCI_LPC_SPI_BASE_ADDR_REG, &io_base_addr);
46	io_base_addr = (io_base_addr & AMD_SPI_BASE_ADDR_MASK) + AMD_HID2_PCI_BAR_OFFSET;
47	amd_spi->io_remap_addr = devm_ioremap(dev, io_base_addr, AMD_HID2_MEM_SIZE);
48
49	if (!amd_spi->io_remap_addr)
50		return -ENOMEM;
51
52	dev_dbg(dev, "io_remap_address: %p\n", amd_spi->io_remap_addr);
53
54	amd_spi->version = AMD_HID2_SPI;
55	host->bus_num = 2;
56
57	return amd_spi_probe_common(dev, host);
58}
59
60static struct pci_driver amd_spi_pci_driver = {
61	.name = "amd_spi_pci",
62	.id_table = pci_spi_ids,
63	.probe = amd_spi_pci_probe,
64};
65
66module_pci_driver(amd_spi_pci_driver);
67
68MODULE_LICENSE("GPL");
69MODULE_DESCRIPTION("AMD HID2 SPI Controller Driver");