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 	struct resource *res_mem;
22 	void __iomem *reg_base;
23 	struct spi_master *master;
24 	struct octeon_spi *p;
25 	int err = -ENOENT;
26 
27 	master = spi_alloc_master(&pdev->dev, sizeof(struct octeon_spi));
28 	if (!master)
29 		return -ENOMEM;
30 	p = spi_master_get_devdata(master);
31 	platform_set_drvdata(pdev, master);
32 
33 	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
34 	reg_base = devm_ioremap_resource(&pdev->dev, res_mem);
35 	if (IS_ERR(reg_base)) {
36 		err = PTR_ERR(reg_base);
37 		goto fail;
38 	}
39 
40 	p->register_base = reg_base;
41 	p->sys_freq = octeon_get_io_clock_rate();
42 
43 	p->regs.config = 0;
44 	p->regs.status = 0x08;
45 	p->regs.tx = 0x10;
46 	p->regs.data = 0x80;
47 
48 	master->num_chipselect = 4;
49 	master->mode_bits = SPI_CPHA |
50 			    SPI_CPOL |
51 			    SPI_CS_HIGH |
52 			    SPI_LSB_FIRST |
53 			    SPI_3WIRE;
54 
55 	master->transfer_one_message = octeon_spi_transfer_one_message;
56 	master->bits_per_word_mask = SPI_BPW_MASK(8);
57 	master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
58 
59 	master->dev.of_node = pdev->dev.of_node;
60 	err = devm_spi_register_master(&pdev->dev, master);
61 	if (err) {
62 		dev_err(&pdev->dev, "register master failed: %d\n", err);
63 		goto fail;
64 	}
65 
66 	dev_info(&pdev->dev, "OCTEON SPI bus driver\n");
67 
68 	return 0;
69 fail:
70 	spi_master_put(master);
71 	return err;
72 }
73 
74 static int octeon_spi_remove(struct platform_device *pdev)
75 {
76 	struct spi_master *master = platform_get_drvdata(pdev);
77 	struct octeon_spi *p = spi_master_get_devdata(master);
78 
79 	/* Clear the CSENA* and put everything in a known state. */
80 	writeq(0, p->register_base + OCTEON_SPI_CFG(p));
81 
82 	return 0;
83 }
84 
85 static const struct of_device_id octeon_spi_match[] = {
86 	{ .compatible = "cavium,octeon-3010-spi", },
87 	{},
88 };
89 MODULE_DEVICE_TABLE(of, octeon_spi_match);
90 
91 static struct platform_driver octeon_spi_driver = {
92 	.driver = {
93 		.name		= "spi-octeon",
94 		.of_match_table = octeon_spi_match,
95 	},
96 	.probe		= octeon_spi_probe,
97 	.remove		= octeon_spi_remove,
98 };
99 
100 module_platform_driver(octeon_spi_driver);
101 
102 MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver");
103 MODULE_AUTHOR("David Daney");
104 MODULE_LICENSE("GPL");
105