GNU Linux-libre 5.10.219-gnu1
[releases.git] / drivers / spi / spi-cavium-octeon.c
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2011, 2012 Cavium, Inc.
7  */
8
9 #include <linux/platform_device.h>
10 #include <linux/spi/spi.h>
11 #include <linux/module.h>
12 #include <linux/io.h>
13 #include <linux/of.h>
14
15 #include <asm/octeon/octeon.h>
16
17 #include "spi-cavium.h"
18
19 static int octeon_spi_probe(struct platform_device *pdev)
20 {
21         void __iomem *reg_base;
22         struct spi_master *master;
23         struct octeon_spi *p;
24         int err = -ENOENT;
25
26         master = spi_alloc_master(&pdev->dev, sizeof(struct octeon_spi));
27         if (!master)
28                 return -ENOMEM;
29         p = spi_master_get_devdata(master);
30         platform_set_drvdata(pdev, master);
31
32         reg_base = devm_platform_ioremap_resource(pdev, 0);
33         if (IS_ERR(reg_base)) {
34                 err = PTR_ERR(reg_base);
35                 goto fail;
36         }
37
38         p->register_base = reg_base;
39         p->sys_freq = octeon_get_io_clock_rate();
40
41         p->regs.config = 0;
42         p->regs.status = 0x08;
43         p->regs.tx = 0x10;
44         p->regs.data = 0x80;
45
46         master->num_chipselect = 4;
47         master->mode_bits = SPI_CPHA |
48                             SPI_CPOL |
49                             SPI_CS_HIGH |
50                             SPI_LSB_FIRST |
51                             SPI_3WIRE;
52
53         master->transfer_one_message = octeon_spi_transfer_one_message;
54         master->bits_per_word_mask = SPI_BPW_MASK(8);
55         master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
56
57         master->dev.of_node = pdev->dev.of_node;
58         err = devm_spi_register_master(&pdev->dev, master);
59         if (err) {
60                 dev_err(&pdev->dev, "register master failed: %d\n", err);
61                 goto fail;
62         }
63
64         dev_info(&pdev->dev, "OCTEON SPI bus driver\n");
65
66         return 0;
67 fail:
68         spi_master_put(master);
69         return err;
70 }
71
72 static int octeon_spi_remove(struct platform_device *pdev)
73 {
74         struct spi_master *master = platform_get_drvdata(pdev);
75         struct octeon_spi *p = spi_master_get_devdata(master);
76
77         /* Clear the CSENA* and put everything in a known state. */
78         writeq(0, p->register_base + OCTEON_SPI_CFG(p));
79
80         return 0;
81 }
82
83 static const struct of_device_id octeon_spi_match[] = {
84         { .compatible = "cavium,octeon-3010-spi", },
85         {},
86 };
87 MODULE_DEVICE_TABLE(of, octeon_spi_match);
88
89 static struct platform_driver octeon_spi_driver = {
90         .driver = {
91                 .name           = "spi-octeon",
92                 .of_match_table = octeon_spi_match,
93         },
94         .probe          = octeon_spi_probe,
95         .remove         = octeon_spi_remove,
96 };
97
98 module_platform_driver(octeon_spi_driver);
99
100 MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver");
101 MODULE_AUTHOR("David Daney");
102 MODULE_LICENSE("GPL");