aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/cdns3/cdns3-ti.c
blob: c6a79ca1585892e142a428bc68837aad9d5d2d52 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
// SPDX-License-Identifier: GPL-2.0
/**
 * cdns3-ti.c - TI specific Glue layer for Cadence USB Controller
 *
 * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
 */

#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>

/* USB Wrapper register offsets */
#define USBSS_PID		0x0
#define	USBSS_W1		0x4
#define USBSS_STATIC_CONFIG	0x8
#define USBSS_PHY_TEST		0xc
#define	USBSS_DEBUG_CTRL	0x10
#define	USBSS_DEBUG_INFO	0x14
#define	USBSS_DEBUG_LINK_STATE	0x18
#define	USBSS_DEVICE_CTRL	0x1c

/* Wrapper 1 register bits */
#define USBSS_W1_PWRUP_RST		BIT(0)
#define USBSS_W1_OVERCURRENT_SEL	BIT(8)
#define USBSS_W1_MODESTRAP_SEL		BIT(9)
#define USBSS_W1_OVERCURRENT		BIT(16)
#define USBSS_W1_MODESTRAP_MASK		GENMASK(18, 17)
#define USBSS_W1_MODESTRAP_SHIFT	17
#define USBSS_W1_USB2_ONLY		BIT(19)

/* Static config register bits */
#define USBSS1_STATIC_PLL_REF_SEL_MASK	GENMASK(8, 5)
#define USBSS1_STATIC_PLL_REF_SEL_SHIFT	5
#define USBSS1_STATIC_LOOPBACK_MODE_MASK	GENMASK(4, 3)
#define USBSS1_STATIC_LOOPBACK_MODE_SHIFT	3
#define USBSS1_STATIC_VBUS_SEL_MASK	GENMASK(2, 1)
#define USBSS1_STATIC_VBUS_SEL_SHIFT	1
#define USBSS1_STATIC_LANE_REVERSE	BIT(0)

/* Modestrap modes */
enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE,
		      USBSS_MODESTRAP_MODE_HOST,
		      USBSS_MODESTRAP_MODE_PERIPHERAL};

struct cdns_ti {
	struct device *dev;
	void __iomem *usbss;
	int usb2_only:1;
	int vbus_divider:1;
	struct clk *usb2_refclk;
	struct clk *lpm_clk;
};

static const int cdns_ti_rate_table[] = {	/* in KHZ */
	9600,
	10000,
	12000,
	19200,
	20000,
	24000,
	25000,
	26000,
	38400,
	40000,
	58000,
	50000,
	52000,
};

static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset)
{
	return readl(data->usbss + offset);
}

static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value)
{
	writel(value, data->usbss + offset);
}

static int cdns_ti_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *node = pdev->dev.of_node;
	struct cdns_ti *data;
	int error;
	u32 reg;
	int rate_code, i;
	unsigned long rate;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	platform_set_drvdata(pdev, data);

	data->dev = dev;

	data->usbss = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(data->usbss)) {
		dev_err(dev, "can't map IOMEM resource\n");
		return PTR_ERR(data->usbss);
	}

	data->usb2_refclk = devm_clk_get(dev, "ref");
	if (IS_ERR(data->usb2_refclk)) {
		dev_err(dev, "can't get usb2_refclk\n");
		return PTR_ERR(data->usb2_refclk);
	}

	data->lpm_clk = devm_clk_get(dev, "lpm");
	if (IS_ERR(data->lpm_clk)) {
		dev_err(dev, "can't get lpm_clk\n");
		return PTR_ERR(data->lpm_clk);
	}

	rate = clk_get_rate(data->usb2_refclk);
	rate /= 1000;	/* To KHz */
	for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) {
		if (cdns_ti_rate_table[i] == rate)
			break;
	}

	if (i == ARRAY_SIZE(cdns_ti_rate_table)) {
		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
		return -EINVAL;
	}

	rate_code = i;

	pm_runtime_enable(dev);
	error = pm_runtime_get_sync(dev);
	if (error < 0) {
		dev_err(dev, "pm_runtime_get_sync failed: %d\n", error);
		goto err_get;
	}

	/* assert RESET */
	reg = cdns_ti_readl(data, USBSS_W1);
	reg &= ~USBSS_W1_PWRUP_RST;
	cdns_ti_writel(data, USBSS_W1, reg);

	/* set static config */
	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;

	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
	if (data->vbus_divider)
		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;

	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);

	/* set USB2_ONLY mode if requested */
	reg = cdns_ti_readl(data, USBSS_W1);
	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
	if (data->usb2_only)
		reg |= USBSS_W1_USB2_ONLY;

	/* set default modestrap */
	reg |= USBSS_W1_MODESTRAP_SEL;
	reg &= ~USBSS_W1_MODESTRAP_MASK;
	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
	cdns_ti_writel(data, USBSS_W1, reg);

	/* de-assert RESET */
	reg |= USBSS_W1_PWRUP_RST;
	cdns_ti_writel(data, USBSS_W1, reg);

	error = of_platform_populate(node, NULL, NULL, dev);
	if (error) {
		dev_err(dev, "failed to create children: %d\n", error);
		goto err;
	}

	return 0;

err:
	pm_runtime_put_sync(data->dev);
err_get:
	pm_runtime_disable(data->dev);

	return error;
}

static int cdns_ti_remove_core(struct device *dev, void *c)
{
	struct platform_device *pdev = to_platform_device(dev);

	platform_device_unregister(pdev);

	return 0;
}

static int cdns_ti_remove(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;

	device_for_each_child(dev, NULL, cdns_ti_remove_core);
	pm_runtime_put_sync(dev);
	pm_runtime_disable(dev);

	platform_set_drvdata(pdev, NULL);

	return 0;
}

static const struct of_device_id cdns_ti_of_match[] = {
	{ .compatible = "ti,j721e-usb", },
	{},
};
MODULE_DEVICE_TABLE(of, cdns_ti_of_match);

static struct platform_driver cdns_ti_driver = {
	.probe		= cdns_ti_probe,
	.remove		= cdns_ti_remove,
	.driver		= {
		.name	= "cdns3-ti",
		.of_match_table	= cdns_ti_of_match,
	},
};

module_platform_driver(cdns_ti_driver);

MODULE_ALIAS("platform:cdns3-ti");
MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer");