Merge tag 'edac_updates_for_5.9_pt2' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6-microblaze.git] / drivers / phy / ti / phy-dm816x-usb.c
1 /*
2  * This program is free software; you can redistribute it and/or
3  * modify it under the terms of the GNU General Public License as
4  * published by the Free Software Foundation version 2.
5  *
6  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
7  * kind, whether express or implied; without even the implied warranty
8  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9  * GNU General Public License for more details.
10  */
11
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/regmap.h>
15
16 #include <linux/slab.h>
17 #include <linux/of.h>
18 #include <linux/io.h>
19 #include <linux/usb/phy_companion.h>
20 #include <linux/clk.h>
21 #include <linux/err.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/delay.h>
24 #include <linux/phy/phy.h>
25 #include <linux/of_platform.h>
26
27 #include <linux/mfd/syscon.h>
28
29 /*
30  * TRM has two sets of USB_CTRL registers.. The correct register bits
31  * are in TRM section 24.9.8.2 USB_CTRL Register. The TRM documents the
32  * phy as being SR70LX Synopsys USB 2.0 OTG nanoPHY. It also seems at
33  * least dm816x rev c ignores writes to USB_CTRL register, but the TI
34  * kernel is writing to those so it's possible that later revisions
35  * have worknig USB_CTRL register.
36  *
37  * Also note that At least USB_CTRL register seems to be dm816x specific
38  * according to the TRM. It's possible that USBPHY_CTRL is more generic,
39  * but that would have to be checked against the SR70LX documentation
40  * which does not seem to be publicly available.
41  *
42  * Finally, the phy on dm814x and am335x is different from dm816x.
43  */
44 #define DM816X_USB_CTRL_PHYCLKSRC       BIT(8)  /* 1 = PLL ref clock */
45 #define DM816X_USB_CTRL_PHYSLEEP1       BIT(1)  /* Enable the first phy */
46 #define DM816X_USB_CTRL_PHYSLEEP0       BIT(0)  /* Enable the second phy */
47
48 #define DM816X_USBPHY_CTRL_TXRISETUNE   1
49 #define DM816X_USBPHY_CTRL_TXVREFTUNE   0xc
50 #define DM816X_USBPHY_CTRL_TXPREEMTUNE  0x2
51
52 struct dm816x_usb_phy {
53         struct regmap *syscon;
54         struct device *dev;
55         unsigned int instance;
56         struct clk *refclk;
57         struct usb_phy phy;
58         unsigned int usb_ctrl;          /* Shared between phy0 and phy1 */
59         unsigned int usbphy_ctrl;
60 };
61
62 static int dm816x_usb_phy_set_host(struct usb_otg *otg, struct usb_bus *host)
63 {
64         otg->host = host;
65         if (!host)
66                 otg->state = OTG_STATE_UNDEFINED;
67
68         return 0;
69 }
70
71 static int dm816x_usb_phy_set_peripheral(struct usb_otg *otg,
72                                          struct usb_gadget *gadget)
73 {
74         otg->gadget = gadget;
75         if (!gadget)
76                 otg->state = OTG_STATE_UNDEFINED;
77
78         return 0;
79 }
80
81 static int dm816x_usb_phy_init(struct phy *x)
82 {
83         struct dm816x_usb_phy *phy = phy_get_drvdata(x);
84         unsigned int val;
85
86         if (clk_get_rate(phy->refclk) != 24000000)
87                 dev_warn(phy->dev, "nonstandard phy refclk\n");
88
89         /* Set PLL ref clock and put phys to sleep */
90         regmap_update_bits(phy->syscon, phy->usb_ctrl,
91                            DM816X_USB_CTRL_PHYCLKSRC |
92                            DM816X_USB_CTRL_PHYSLEEP1 |
93                            DM816X_USB_CTRL_PHYSLEEP0,
94                            0);
95         regmap_read(phy->syscon, phy->usb_ctrl, &val);
96         if ((val & 3) != 0)
97                 dev_info(phy->dev,
98                          "Working dm816x USB_CTRL! (0x%08x)\n",
99                          val);
100
101         /*
102          * TI kernel sets these values for "symmetrical eye diagram and
103          * better signal quality" so let's assume somebody checked the
104          * values with a scope and set them here too.
105          */
106         regmap_read(phy->syscon, phy->usbphy_ctrl, &val);
107         val |= DM816X_USBPHY_CTRL_TXRISETUNE |
108                 DM816X_USBPHY_CTRL_TXVREFTUNE |
109                 DM816X_USBPHY_CTRL_TXPREEMTUNE;
110         regmap_write(phy->syscon, phy->usbphy_ctrl, val);
111
112         return 0;
113 }
114
115 static const struct phy_ops ops = {
116         .init           = dm816x_usb_phy_init,
117         .owner          = THIS_MODULE,
118 };
119
120 static int __maybe_unused dm816x_usb_phy_runtime_suspend(struct device *dev)
121 {
122         struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
123         unsigned int mask, val;
124         int error = 0;
125
126         mask = BIT(phy->instance);
127         val = ~BIT(phy->instance);
128         error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
129                                    mask, val);
130         if (error)
131                 dev_err(phy->dev, "phy%i failed to power off\n",
132                         phy->instance);
133         clk_disable(phy->refclk);
134
135         return 0;
136 }
137
138 static int __maybe_unused dm816x_usb_phy_runtime_resume(struct device *dev)
139 {
140         struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
141         unsigned int mask, val;
142         int error;
143
144         error = clk_enable(phy->refclk);
145         if (error)
146                 return error;
147
148         /*
149          * Note that at least dm816x rev c does not seem to do
150          * anything with the USB_CTRL register. But let's follow
151          * what the TI tree is doing in case later revisions use
152          * USB_CTRL.
153          */
154         mask = BIT(phy->instance);
155         val = BIT(phy->instance);
156         error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
157                                    mask, val);
158         if (error) {
159                 dev_err(phy->dev, "phy%i failed to power on\n",
160                         phy->instance);
161                 clk_disable(phy->refclk);
162                 return error;
163         }
164
165         return 0;
166 }
167
168 static UNIVERSAL_DEV_PM_OPS(dm816x_usb_phy_pm_ops,
169                             dm816x_usb_phy_runtime_suspend,
170                             dm816x_usb_phy_runtime_resume,
171                             NULL);
172
173 #ifdef CONFIG_OF
174 static const struct of_device_id dm816x_usb_phy_id_table[] = {
175         {
176                 .compatible = "ti,dm8168-usb-phy",
177         },
178         {},
179 };
180 MODULE_DEVICE_TABLE(of, dm816x_usb_phy_id_table);
181 #endif
182
183 static int dm816x_usb_phy_probe(struct platform_device *pdev)
184 {
185         struct dm816x_usb_phy *phy;
186         struct resource *res;
187         struct phy *generic_phy;
188         struct phy_provider *phy_provider;
189         struct usb_otg *otg;
190         const struct of_device_id *of_id;
191         int error;
192
193         of_id = of_match_device(of_match_ptr(dm816x_usb_phy_id_table),
194                                 &pdev->dev);
195         if (!of_id)
196                 return -EINVAL;
197
198         phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
199         if (!phy)
200                 return -ENOMEM;
201
202         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
203         if (!res)
204                 return -ENOENT;
205
206         phy->syscon = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
207                                                       "syscon");
208         if (IS_ERR(phy->syscon))
209                 return PTR_ERR(phy->syscon);
210
211         /*
212          * According to sprs614e.pdf, the first usb_ctrl is shared and
213          * the second instance for usb_ctrl is reserved.. Also the
214          * register bits are different from earlier TRMs.
215          */
216         phy->usb_ctrl = 0x20;
217         phy->usbphy_ctrl = (res->start & 0xff) + 4;
218         if (phy->usbphy_ctrl == 0x2c)
219                 phy->instance = 1;
220
221         otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
222         if (!otg)
223                 return -ENOMEM;
224
225         phy->dev = &pdev->dev;
226         phy->phy.dev = phy->dev;
227         phy->phy.label = "dm8168_usb_phy";
228         phy->phy.otg = otg;
229         phy->phy.type = USB_PHY_TYPE_USB2;
230         otg->set_host = dm816x_usb_phy_set_host;
231         otg->set_peripheral = dm816x_usb_phy_set_peripheral;
232         otg->usb_phy = &phy->phy;
233
234         platform_set_drvdata(pdev, phy);
235
236         phy->refclk = devm_clk_get(phy->dev, "refclk");
237         if (IS_ERR(phy->refclk))
238                 return PTR_ERR(phy->refclk);
239         error = clk_prepare(phy->refclk);
240         if (error)
241                 return error;
242
243         pm_runtime_enable(phy->dev);
244         generic_phy = devm_phy_create(phy->dev, NULL, &ops);
245         if (IS_ERR(generic_phy))
246                 return PTR_ERR(generic_phy);
247
248         phy_set_drvdata(generic_phy, phy);
249
250         phy_provider = devm_of_phy_provider_register(phy->dev,
251                                                      of_phy_simple_xlate);
252         if (IS_ERR(phy_provider))
253                 return PTR_ERR(phy_provider);
254
255         usb_add_phy_dev(&phy->phy);
256
257         return 0;
258 }
259
260 static int dm816x_usb_phy_remove(struct platform_device *pdev)
261 {
262         struct dm816x_usb_phy *phy = platform_get_drvdata(pdev);
263
264         usb_remove_phy(&phy->phy);
265         pm_runtime_disable(phy->dev);
266         clk_unprepare(phy->refclk);
267
268         return 0;
269 }
270
271 static struct platform_driver dm816x_usb_phy_driver = {
272         .probe          = dm816x_usb_phy_probe,
273         .remove         = dm816x_usb_phy_remove,
274         .driver         = {
275                 .name   = "dm816x-usb-phy",
276                 .pm     = &dm816x_usb_phy_pm_ops,
277                 .of_match_table = of_match_ptr(dm816x_usb_phy_id_table),
278         },
279 };
280
281 module_platform_driver(dm816x_usb_phy_driver);
282
283 MODULE_ALIAS("platform:dm816x_usb");
284 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
285 MODULE_DESCRIPTION("dm816x usb phy driver");
286 MODULE_LICENSE("GPL v2");