1// SPDX-License-Identifier: GPL-2.0
2/* DSA driver for:
3 * Vitesse VSC7385 SparX-G5 5+1-port Integrated Gigabit Ethernet Switch
4 * Vitesse VSC7388 SparX-G8 8-port Integrated Gigabit Ethernet Switch
5 * Vitesse VSC7395 SparX-G5e 5+1-port Integrated Gigabit Ethernet Switch
6 * Vitesse VSC7398 SparX-G8e 8-port Integrated Gigabit Ethernet Switch
7 *
8 * This driver takes control of the switch chip connected over CPU-attached
9 * address bus and configures it to route packages around when connected to
10 * a CPU port.
11 *
12 * Copyright (C) 2019 Pawel Dembicki <paweldembicki@gmail.com>
13 * Based on vitesse-vsc-spi.c by:
14 * Copyright (C) 2018 Linus Wallej <linus.walleij@linaro.org>
15 * Includes portions of code from the firmware uploader by:
16 * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
17 */
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/platform_device.h>
22
23#include "vitesse-vsc73xx.h"
24
25#define VSC73XX_CMD_PLATFORM_BLOCK_SHIFT		14
26#define VSC73XX_CMD_PLATFORM_BLOCK_MASK			0x7
27#define VSC73XX_CMD_PLATFORM_SUBBLOCK_SHIFT		10
28#define VSC73XX_CMD_PLATFORM_SUBBLOCK_MASK		0xf
29#define VSC73XX_CMD_PLATFORM_REGISTER_SHIFT		2
30
31/*
32 * struct vsc73xx_platform - VSC73xx Platform state container
33 */
34struct vsc73xx_platform {
35	struct platform_device	*pdev;
36	void __iomem		*base_addr;
37	struct vsc73xx		vsc;
38};
39
40static const struct vsc73xx_ops vsc73xx_platform_ops;
41
42static u32 vsc73xx_make_addr(u8 block, u8 subblock, u8 reg)
43{
44	u32 ret;
45
46	ret = (block & VSC73XX_CMD_PLATFORM_BLOCK_MASK)
47	    << VSC73XX_CMD_PLATFORM_BLOCK_SHIFT;
48	ret |= (subblock & VSC73XX_CMD_PLATFORM_SUBBLOCK_MASK)
49	    << VSC73XX_CMD_PLATFORM_SUBBLOCK_SHIFT;
50	ret |= reg << VSC73XX_CMD_PLATFORM_REGISTER_SHIFT;
51
52	return ret;
53}
54
55static int vsc73xx_platform_read(struct vsc73xx *vsc, u8 block, u8 subblock,
56				 u8 reg, u32 *val)
57{
58	struct vsc73xx_platform *vsc_platform = vsc->priv;
59	u32 offset;
60
61	if (!vsc73xx_is_addr_valid(block, subblock))
62		return -EINVAL;
63
64	offset = vsc73xx_make_addr(block, subblock, reg);
65	/* By default vsc73xx running in big-endian mode.
66	 * (See "Register Addressing" section 5.5.3 in the VSC7385 manual.)
67	 */
68	*val = ioread32be(vsc_platform->base_addr + offset);
69
70	return 0;
71}
72
73static int vsc73xx_platform_write(struct vsc73xx *vsc, u8 block, u8 subblock,
74				  u8 reg, u32 val)
75{
76	struct vsc73xx_platform *vsc_platform = vsc->priv;
77	u32 offset;
78
79	if (!vsc73xx_is_addr_valid(block, subblock))
80		return -EINVAL;
81
82	offset = vsc73xx_make_addr(block, subblock, reg);
83	iowrite32be(val, vsc_platform->base_addr + offset);
84
85	return 0;
86}
87
88static int vsc73xx_platform_probe(struct platform_device *pdev)
89{
90	struct device *dev = &pdev->dev;
91	struct vsc73xx_platform *vsc_platform;
92	int ret;
93
94	vsc_platform = devm_kzalloc(dev, sizeof(*vsc_platform), GFP_KERNEL);
95	if (!vsc_platform)
96		return -ENOMEM;
97
98	platform_set_drvdata(pdev, vsc_platform);
99	vsc_platform->pdev = pdev;
100	vsc_platform->vsc.dev = dev;
101	vsc_platform->vsc.priv = vsc_platform;
102	vsc_platform->vsc.ops = &vsc73xx_platform_ops;
103
104	/* obtain I/O memory space */
105	vsc_platform->base_addr = devm_platform_ioremap_resource(pdev, 0);
106	if (IS_ERR(vsc_platform->base_addr)) {
107		dev_err(&pdev->dev, "cannot request I/O memory space\n");
108		ret = -ENXIO;
109		return ret;
110	}
111
112	return vsc73xx_probe(&vsc_platform->vsc);
113}
114
115static int vsc73xx_platform_remove(struct platform_device *pdev)
116{
117	struct vsc73xx_platform *vsc_platform = platform_get_drvdata(pdev);
118
119	return vsc73xx_remove(&vsc_platform->vsc);
120}
121
122static const struct vsc73xx_ops vsc73xx_platform_ops = {
123	.read = vsc73xx_platform_read,
124	.write = vsc73xx_platform_write,
125};
126
127static const struct of_device_id vsc73xx_of_match[] = {
128	{
129		.compatible = "vitesse,vsc7385",
130	},
131	{
132		.compatible = "vitesse,vsc7388",
133	},
134	{
135		.compatible = "vitesse,vsc7395",
136	},
137	{
138		.compatible = "vitesse,vsc7398",
139	},
140	{ },
141};
142MODULE_DEVICE_TABLE(of, vsc73xx_of_match);
143
144static struct platform_driver vsc73xx_platform_driver = {
145	.probe = vsc73xx_platform_probe,
146	.remove = vsc73xx_platform_remove,
147	.driver = {
148		.name = "vsc73xx-platform",
149		.of_match_table = vsc73xx_of_match,
150	},
151};
152module_platform_driver(vsc73xx_platform_driver);
153
154MODULE_AUTHOR("Pawel Dembicki <paweldembicki@gmail.com>");
155MODULE_DESCRIPTION("Vitesse VSC7385/7388/7395/7398 Platform driver");
156MODULE_LICENSE("GPL v2");
157