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
thunderx_spi_probe(struct pci_dev * pdev,const struct pci_device_id * ent)19 static 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
84 error:
85 clk_disable_unprepare(p->clk);
86 pci_release_regions(pdev);
87 spi_master_put(master);
88 return ret;
89 }
90
thunderx_spi_remove(struct pci_dev * pdev)91 static 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
106 static const struct pci_device_id thunderx_spi_pci_id_table[] = {
107 { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa00b) },
108 { 0, }
109 };
110
111 MODULE_DEVICE_TABLE(pci, thunderx_spi_pci_id_table);
112
113 static 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
120 module_pci_driver(thunderx_spi_driver);
121
122 MODULE_DESCRIPTION("Cavium, Inc. ThunderX SPI bus driver");
123 MODULE_AUTHOR("Jan Glauber");
124 MODULE_LICENSE("GPL");
125