xref: /openbmc/linux/drivers/usb/phy/phy-mxs-usb.c (revision 2400780e)
1 /*
2  * Copyright 2012-2013 Freescale Semiconductor, Inc.
3  * Copyright (C) 2012 Marek Vasut <marex@denx.de>
4  * on behalf of DENX Software Engineering GmbH
5  *
6  * The code contained herein is licensed under the GNU General Public
7  * License. You may obtain a copy of the GNU General Public License
8  * Version 2 or later at the following locations:
9  *
10  * http://www.opensource.org/licenses/gpl-license.html
11  * http://www.gnu.org/copyleft/gpl.html
12  */
13 
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/platform_device.h>
17 #include <linux/clk.h>
18 #include <linux/usb/otg.h>
19 #include <linux/stmp_device.h>
20 #include <linux/delay.h>
21 #include <linux/err.h>
22 #include <linux/io.h>
23 #include <linux/of_device.h>
24 
25 #define DRIVER_NAME "mxs_phy"
26 
27 #define HW_USBPHY_PWD				0x00
28 #define HW_USBPHY_CTRL				0x30
29 #define HW_USBPHY_CTRL_SET			0x34
30 #define HW_USBPHY_CTRL_CLR			0x38
31 
32 #define BM_USBPHY_CTRL_SFTRST			BIT(31)
33 #define BM_USBPHY_CTRL_CLKGATE			BIT(30)
34 #define BM_USBPHY_CTRL_ENUTMILEVEL3		BIT(15)
35 #define BM_USBPHY_CTRL_ENUTMILEVEL2		BIT(14)
36 #define BM_USBPHY_CTRL_ENHOSTDISCONDETECT	BIT(1)
37 
38 #define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
39 
40 /* Do disconnection between PHY and controller without vbus */
41 #define MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS	BIT(0)
42 
43 /*
44  * The PHY will be in messy if there is a wakeup after putting
45  * bus to suspend (set portsc.suspendM) but before setting PHY to low
46  * power mode (set portsc.phcd).
47  */
48 #define MXS_PHY_ABNORMAL_IN_SUSPEND		BIT(1)
49 
50 /*
51  * The SOF sends too fast after resuming, it will cause disconnection
52  * between host and high speed device.
53  */
54 #define MXS_PHY_SENDING_SOF_TOO_FAST		BIT(2)
55 
56 struct mxs_phy_data {
57 	unsigned int flags;
58 };
59 
60 static const struct mxs_phy_data imx23_phy_data = {
61 	.flags = MXS_PHY_ABNORMAL_IN_SUSPEND | MXS_PHY_SENDING_SOF_TOO_FAST,
62 };
63 
64 static const struct mxs_phy_data imx6q_phy_data = {
65 	.flags = MXS_PHY_SENDING_SOF_TOO_FAST |
66 		MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS,
67 };
68 
69 static const struct mxs_phy_data imx6sl_phy_data = {
70 	.flags = MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS,
71 };
72 
73 static const struct of_device_id mxs_phy_dt_ids[] = {
74 	{ .compatible = "fsl,imx6sl-usbphy", .data = &imx6sl_phy_data, },
75 	{ .compatible = "fsl,imx6q-usbphy", .data = &imx6q_phy_data, },
76 	{ .compatible = "fsl,imx23-usbphy", .data = &imx23_phy_data, },
77 	{ /* sentinel */ }
78 };
79 MODULE_DEVICE_TABLE(of, mxs_phy_dt_ids);
80 
81 struct mxs_phy {
82 	struct usb_phy phy;
83 	struct clk *clk;
84 	const struct mxs_phy_data *data;
85 };
86 
87 static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
88 {
89 	int ret;
90 	void __iomem *base = mxs_phy->phy.io_priv;
91 
92 	ret = stmp_reset_block(base + HW_USBPHY_CTRL);
93 	if (ret)
94 		return ret;
95 
96 	/* Power up the PHY */
97 	writel(0, base + HW_USBPHY_PWD);
98 
99 	/* enable FS/LS device */
100 	writel(BM_USBPHY_CTRL_ENUTMILEVEL2 |
101 	       BM_USBPHY_CTRL_ENUTMILEVEL3,
102 	       base + HW_USBPHY_CTRL_SET);
103 
104 	return 0;
105 }
106 
107 static int mxs_phy_init(struct usb_phy *phy)
108 {
109 	int ret;
110 	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
111 
112 	ret = clk_prepare_enable(mxs_phy->clk);
113 	if (ret)
114 		return ret;
115 
116 	return mxs_phy_hw_init(mxs_phy);
117 }
118 
119 static void mxs_phy_shutdown(struct usb_phy *phy)
120 {
121 	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
122 
123 	writel(BM_USBPHY_CTRL_CLKGATE,
124 	       phy->io_priv + HW_USBPHY_CTRL_SET);
125 
126 	clk_disable_unprepare(mxs_phy->clk);
127 }
128 
129 static int mxs_phy_suspend(struct usb_phy *x, int suspend)
130 {
131 	int ret;
132 	struct mxs_phy *mxs_phy = to_mxs_phy(x);
133 
134 	if (suspend) {
135 		writel(0xffffffff, x->io_priv + HW_USBPHY_PWD);
136 		writel(BM_USBPHY_CTRL_CLKGATE,
137 		       x->io_priv + HW_USBPHY_CTRL_SET);
138 		clk_disable_unprepare(mxs_phy->clk);
139 	} else {
140 		ret = clk_prepare_enable(mxs_phy->clk);
141 		if (ret)
142 			return ret;
143 		writel(BM_USBPHY_CTRL_CLKGATE,
144 		       x->io_priv + HW_USBPHY_CTRL_CLR);
145 		writel(0, x->io_priv + HW_USBPHY_PWD);
146 	}
147 
148 	return 0;
149 }
150 
151 static int mxs_phy_on_connect(struct usb_phy *phy,
152 		enum usb_device_speed speed)
153 {
154 	dev_dbg(phy->dev, "%s speed device has connected\n",
155 		(speed == USB_SPEED_HIGH) ? "high" : "non-high");
156 
157 	if (speed == USB_SPEED_HIGH)
158 		writel(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
159 		       phy->io_priv + HW_USBPHY_CTRL_SET);
160 
161 	return 0;
162 }
163 
164 static int mxs_phy_on_disconnect(struct usb_phy *phy,
165 		enum usb_device_speed speed)
166 {
167 	dev_dbg(phy->dev, "%s speed device has disconnected\n",
168 		(speed == USB_SPEED_HIGH) ? "high" : "non-high");
169 
170 	if (speed == USB_SPEED_HIGH)
171 		writel(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
172 		       phy->io_priv + HW_USBPHY_CTRL_CLR);
173 
174 	return 0;
175 }
176 
177 static int mxs_phy_probe(struct platform_device *pdev)
178 {
179 	struct resource *res;
180 	void __iomem *base;
181 	struct clk *clk;
182 	struct mxs_phy *mxs_phy;
183 	int ret;
184 	const struct of_device_id *of_id =
185 			of_match_device(mxs_phy_dt_ids, &pdev->dev);
186 
187 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
188 	base = devm_ioremap_resource(&pdev->dev, res);
189 	if (IS_ERR(base))
190 		return PTR_ERR(base);
191 
192 	clk = devm_clk_get(&pdev->dev, NULL);
193 	if (IS_ERR(clk)) {
194 		dev_err(&pdev->dev,
195 			"can't get the clock, err=%ld", PTR_ERR(clk));
196 		return PTR_ERR(clk);
197 	}
198 
199 	mxs_phy = devm_kzalloc(&pdev->dev, sizeof(*mxs_phy), GFP_KERNEL);
200 	if (!mxs_phy) {
201 		dev_err(&pdev->dev, "Failed to allocate USB PHY structure!\n");
202 		return -ENOMEM;
203 	}
204 
205 	mxs_phy->phy.io_priv		= base;
206 	mxs_phy->phy.dev		= &pdev->dev;
207 	mxs_phy->phy.label		= DRIVER_NAME;
208 	mxs_phy->phy.init		= mxs_phy_init;
209 	mxs_phy->phy.shutdown		= mxs_phy_shutdown;
210 	mxs_phy->phy.set_suspend	= mxs_phy_suspend;
211 	mxs_phy->phy.notify_connect	= mxs_phy_on_connect;
212 	mxs_phy->phy.notify_disconnect	= mxs_phy_on_disconnect;
213 	mxs_phy->phy.type		= USB_PHY_TYPE_USB2;
214 
215 	mxs_phy->clk = clk;
216 	mxs_phy->data = of_id->data;
217 
218 	platform_set_drvdata(pdev, mxs_phy);
219 
220 	ret = usb_add_phy_dev(&mxs_phy->phy);
221 	if (ret)
222 		return ret;
223 
224 	return 0;
225 }
226 
227 static int mxs_phy_remove(struct platform_device *pdev)
228 {
229 	struct mxs_phy *mxs_phy = platform_get_drvdata(pdev);
230 
231 	usb_remove_phy(&mxs_phy->phy);
232 
233 	return 0;
234 }
235 
236 static struct platform_driver mxs_phy_driver = {
237 	.probe = mxs_phy_probe,
238 	.remove = mxs_phy_remove,
239 	.driver = {
240 		.name = DRIVER_NAME,
241 		.owner	= THIS_MODULE,
242 		.of_match_table = mxs_phy_dt_ids,
243 	 },
244 };
245 
246 static int __init mxs_phy_module_init(void)
247 {
248 	return platform_driver_register(&mxs_phy_driver);
249 }
250 postcore_initcall(mxs_phy_module_init);
251 
252 static void __exit mxs_phy_module_exit(void)
253 {
254 	platform_driver_unregister(&mxs_phy_driver);
255 }
256 module_exit(mxs_phy_module_exit);
257 
258 MODULE_ALIAS("platform:mxs-usb-phy");
259 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
260 MODULE_AUTHOR("Richard Zhao <richard.zhao@freescale.com>");
261 MODULE_DESCRIPTION("Freescale MXS USB PHY driver");
262 MODULE_LICENSE("GPL");
263