1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Cavium ThunderX SPI driver.
  4 *
  5 * Copyright (C) 2016 Cavium Inc.
  6 * Authors: Jan Glauber <jglauber@cavium.com>
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/pci.h>
 11#include <linux/spi/spi.h>
 12
 13#include "spi-cavium.h"
 14
 15#define DRV_NAME "spi-thunderx"
 16
 17#define SYS_FREQ_DEFAULT 700000000 /* 700 Mhz */
 18
 19static int thunderx_spi_probe(struct pci_dev *pdev,
 20			      const struct pci_device_id *ent)
 21{
 22	struct device *dev = &pdev->dev;
 23	struct spi_master *master;
 24	struct octeon_spi *p;
 25	int ret;
 26
 27	master = spi_alloc_master(dev, sizeof(struct octeon_spi));
 28	if (!master)
 29		return -ENOMEM;
 30
 31	p = spi_master_get_devdata(master);
 32
 33	ret = pcim_enable_device(pdev);
 34	if (ret)
 35		goto error;
 36
 37	ret = pci_request_regions(pdev, DRV_NAME);
 38	if (ret)
 39		goto error;
 40
 41	p->register_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
 42	if (!p->register_base) {
 43		ret = -EINVAL;
 44		goto error;
 45	}
 46
 47	p->regs.config = 0x1000;
 48	p->regs.status = 0x1008;
 49	p->regs.tx = 0x1010;
 50	p->regs.data = 0x1080;
 51
 52	p->clk = devm_clk_get(dev, NULL);
 53	if (IS_ERR(p->clk)) {
 54		ret = PTR_ERR(p->clk);
 55		goto error;
 56	}
 57
 58	ret = clk_prepare_enable(p->clk);
 59	if (ret)
 60		goto error;
 61
 62	p->sys_freq = clk_get_rate(p->clk);
 63	if (!p->sys_freq)
 64		p->sys_freq = SYS_FREQ_DEFAULT;
 65	dev_info(dev, "Set system clock to %u\n", p->sys_freq);
 66
 67	master->flags = SPI_MASTER_HALF_DUPLEX;
 68	master->num_chipselect = 4;
 69	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH |
 70			    SPI_LSB_FIRST | SPI_3WIRE;
 71	master->transfer_one_message = octeon_spi_transfer_one_message;
 72	master->bits_per_word_mask = SPI_BPW_MASK(8);
 73	master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
 74	master->dev.of_node = pdev->dev.of_node;
 75
 76	pci_set_drvdata(pdev, master);
 77
 78	ret = devm_spi_register_master(dev, master);
 79	if (ret)
 80		goto error;
 81
 82	return 0;
 83
 84error:
 85	clk_disable_unprepare(p->clk);
 86	pci_release_regions(pdev);
 87	spi_master_put(master);
 88	return ret;
 89}
 90
 91static void thunderx_spi_remove(struct pci_dev *pdev)
 92{
 93	struct spi_master *master = pci_get_drvdata(pdev);
 94	struct octeon_spi *p;
 95
 96	p = spi_master_get_devdata(master);
 97	if (!p)
 98		return;
 99
100	clk_disable_unprepare(p->clk);
101	pci_release_regions(pdev);
102	/* Put everything in a known state. */
103	writeq(0, p->register_base + OCTEON_SPI_CFG(p));
104}
105
106static const struct pci_device_id thunderx_spi_pci_id_table[] = {
107	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa00b) },
108	{ 0, }
109};
110
111MODULE_DEVICE_TABLE(pci, thunderx_spi_pci_id_table);
112
113static struct pci_driver thunderx_spi_driver = {
114	.name		= DRV_NAME,
115	.id_table	= thunderx_spi_pci_id_table,
116	.probe		= thunderx_spi_probe,
117	.remove		= thunderx_spi_remove,
118};
119
120module_pci_driver(thunderx_spi_driver);
121
122MODULE_DESCRIPTION("Cavium, Inc. ThunderX SPI bus driver");
123MODULE_AUTHOR("Jan Glauber");
124MODULE_LICENSE("GPL");