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 
octeon_spi_probe(struct platform_device * pdev)19 static int octeon_spi_probe(struct platform_device *pdev)
20 {
21 	void __iomem *reg_base;
22 	struct spi_controller *host;
23 	struct octeon_spi *p;
24 	int err = -ENOENT;
25 
26 	host = spi_alloc_host(&pdev->dev, sizeof(struct octeon_spi));
27 	if (!host)
28 		return -ENOMEM;
29 	p = spi_controller_get_devdata(host);
30 	platform_set_drvdata(pdev, host);
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 	host->num_chipselect = 4;
47 	host->mode_bits = SPI_CPHA |
48 			    SPI_CPOL |
49 			    SPI_CS_HIGH |
50 			    SPI_LSB_FIRST |
51 			    SPI_3WIRE;
52 
53 	host->transfer_one_message = octeon_spi_transfer_one_message;
54 	host->bits_per_word_mask = SPI_BPW_MASK(8);
55 	host->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
56 
57 	host->dev.of_node = pdev->dev.of_node;
58 	err = devm_spi_register_controller(&pdev->dev, host);
59 	if (err) {
60 		dev_err(&pdev->dev, "register host 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_controller_put(host);
69 	return err;
70 }
71 
octeon_spi_remove(struct platform_device * pdev)72 static void octeon_spi_remove(struct platform_device *pdev)
73 {
74 	struct spi_controller *host = platform_get_drvdata(pdev);
75 	struct octeon_spi *p = spi_controller_get_devdata(host);
76 
77 	/* Clear the CSENA* and put everything in a known state. */
78 	writeq(0, p->register_base + OCTEON_SPI_CFG(p));
79 }
80 
81 static const struct of_device_id octeon_spi_match[] = {
82 	{ .compatible = "cavium,octeon-3010-spi", },
83 	{},
84 };
85 MODULE_DEVICE_TABLE(of, octeon_spi_match);
86 
87 static struct platform_driver octeon_spi_driver = {
88 	.driver = {
89 		.name		= "spi-octeon",
90 		.of_match_table = octeon_spi_match,
91 	},
92 	.probe		= octeon_spi_probe,
93 	.remove_new	= octeon_spi_remove,
94 };
95 
96 module_platform_driver(octeon_spi_driver);
97 
98 MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver");
99 MODULE_AUTHOR("David Daney");
100 MODULE_LICENSE("GPL");
101