1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Intel LGM USB PHY driver |
4 | * |
5 | * Copyright (C) 2020 Intel Corporation. |
6 | */ |
7 | |
8 | #include <linux/bitfield.h> |
9 | #include <linux/delay.h> |
10 | #include <linux/iopoll.h> |
11 | #include <linux/module.h> |
12 | #include <linux/of.h> |
13 | #include <linux/platform_device.h> |
14 | #include <linux/regulator/consumer.h> |
15 | #include <linux/reset.h> |
16 | #include <linux/usb/phy.h> |
17 | #include <linux/workqueue.h> |
18 | |
19 | #define CTRL1_OFFSET 0x14 |
20 | #define SRAM_EXT_LD_DONE BIT(25) |
21 | #define SRAM_INIT_DONE BIT(26) |
22 | |
23 | #define TCPC_OFFSET 0x1014 |
24 | #define TCPC_MUX_CTL GENMASK(1, 0) |
25 | #define MUX_NC 0 |
26 | #define MUX_USB 1 |
27 | #define MUX_DP 2 |
28 | #define MUX_USBDP 3 |
29 | #define TCPC_FLIPPED BIT(2) |
30 | #define TCPC_LOW_POWER_EN BIT(3) |
31 | #define TCPC_VALID BIT(4) |
32 | #define TCPC_CONN \ |
33 | (TCPC_VALID | FIELD_PREP(TCPC_MUX_CTL, MUX_USB)) |
34 | #define TCPC_DISCONN \ |
35 | (TCPC_VALID | FIELD_PREP(TCPC_MUX_CTL, MUX_NC) | TCPC_LOW_POWER_EN) |
36 | |
37 | static const char *const PHY_RESETS[] = { "phy31" , "phy" , }; |
38 | static const char *const CTL_RESETS[] = { "apb" , "ctrl" , }; |
39 | |
40 | struct tca_apb { |
41 | struct reset_control *resets[ARRAY_SIZE(PHY_RESETS)]; |
42 | struct regulator *vbus; |
43 | struct work_struct wk; |
44 | struct usb_phy phy; |
45 | |
46 | bool regulator_enabled; |
47 | bool phy_initialized; |
48 | bool connected; |
49 | }; |
50 | |
51 | static int get_flipped(struct tca_apb *ta, bool *flipped) |
52 | { |
53 | union extcon_property_value property; |
54 | int ret; |
55 | |
56 | ret = extcon_get_property(edev: ta->phy.edev, EXTCON_USB_HOST, |
57 | EXTCON_PROP_USB_TYPEC_POLARITY, prop_val: &property); |
58 | if (ret) { |
59 | dev_err(ta->phy.dev, "no polarity property from extcon\n" ); |
60 | return ret; |
61 | } |
62 | |
63 | *flipped = property.intval; |
64 | |
65 | return 0; |
66 | } |
67 | |
68 | static int phy_init(struct usb_phy *phy) |
69 | { |
70 | struct tca_apb *ta = container_of(phy, struct tca_apb, phy); |
71 | void __iomem *ctrl1 = phy->io_priv + CTRL1_OFFSET; |
72 | int val, ret, i; |
73 | |
74 | if (ta->phy_initialized) |
75 | return 0; |
76 | |
77 | for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) |
78 | reset_control_deassert(rstc: ta->resets[i]); |
79 | |
80 | ret = readl_poll_timeout(ctrl1, val, val & SRAM_INIT_DONE, 10, 10 * 1000); |
81 | if (ret) { |
82 | dev_err(ta->phy.dev, "SRAM init failed, 0x%x\n" , val); |
83 | return ret; |
84 | } |
85 | |
86 | writel(readl(addr: ctrl1) | SRAM_EXT_LD_DONE, addr: ctrl1); |
87 | |
88 | ta->phy_initialized = true; |
89 | if (!ta->phy.edev) { |
90 | writel(TCPC_CONN, addr: ta->phy.io_priv + TCPC_OFFSET); |
91 | return phy->set_vbus(phy, true); |
92 | } |
93 | |
94 | schedule_work(work: &ta->wk); |
95 | |
96 | return ret; |
97 | } |
98 | |
99 | static void phy_shutdown(struct usb_phy *phy) |
100 | { |
101 | struct tca_apb *ta = container_of(phy, struct tca_apb, phy); |
102 | int i; |
103 | |
104 | if (!ta->phy_initialized) |
105 | return; |
106 | |
107 | ta->phy_initialized = false; |
108 | flush_work(work: &ta->wk); |
109 | ta->phy.set_vbus(&ta->phy, false); |
110 | |
111 | ta->connected = false; |
112 | writel(TCPC_DISCONN, addr: ta->phy.io_priv + TCPC_OFFSET); |
113 | |
114 | for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) |
115 | reset_control_assert(rstc: ta->resets[i]); |
116 | } |
117 | |
118 | static int phy_set_vbus(struct usb_phy *phy, int on) |
119 | { |
120 | struct tca_apb *ta = container_of(phy, struct tca_apb, phy); |
121 | int ret; |
122 | |
123 | if (!!on == ta->regulator_enabled) |
124 | return 0; |
125 | |
126 | if (on) |
127 | ret = regulator_enable(regulator: ta->vbus); |
128 | else |
129 | ret = regulator_disable(regulator: ta->vbus); |
130 | |
131 | if (!ret) |
132 | ta->regulator_enabled = on; |
133 | |
134 | dev_dbg(ta->phy.dev, "set vbus: %d\n" , on); |
135 | return ret; |
136 | } |
137 | |
138 | static void tca_work(struct work_struct *work) |
139 | { |
140 | struct tca_apb *ta = container_of(work, struct tca_apb, wk); |
141 | bool connected; |
142 | bool flipped = false; |
143 | u32 val; |
144 | int ret; |
145 | |
146 | ret = get_flipped(ta, flipped: &flipped); |
147 | if (ret) |
148 | return; |
149 | |
150 | connected = extcon_get_state(edev: ta->phy.edev, EXTCON_USB_HOST); |
151 | if (connected == ta->connected) |
152 | return; |
153 | |
154 | ta->connected = connected; |
155 | if (connected) { |
156 | val = TCPC_CONN; |
157 | if (flipped) |
158 | val |= TCPC_FLIPPED; |
159 | dev_dbg(ta->phy.dev, "connected%s\n" , flipped ? " flipped" : "" ); |
160 | } else { |
161 | val = TCPC_DISCONN; |
162 | dev_dbg(ta->phy.dev, "disconnected\n" ); |
163 | } |
164 | |
165 | writel(val, addr: ta->phy.io_priv + TCPC_OFFSET); |
166 | |
167 | ret = ta->phy.set_vbus(&ta->phy, connected); |
168 | if (ret) |
169 | dev_err(ta->phy.dev, "failed to set VBUS\n" ); |
170 | } |
171 | |
172 | static int id_notifier(struct notifier_block *nb, unsigned long event, void *ptr) |
173 | { |
174 | struct tca_apb *ta = container_of(nb, struct tca_apb, phy.id_nb); |
175 | |
176 | if (ta->phy_initialized) |
177 | schedule_work(work: &ta->wk); |
178 | |
179 | return NOTIFY_DONE; |
180 | } |
181 | |
182 | static int vbus_notifier(struct notifier_block *nb, unsigned long evnt, void *ptr) |
183 | { |
184 | return NOTIFY_DONE; |
185 | } |
186 | |
187 | static int phy_probe(struct platform_device *pdev) |
188 | { |
189 | struct reset_control *resets[ARRAY_SIZE(CTL_RESETS)]; |
190 | struct device *dev = &pdev->dev; |
191 | struct usb_phy *phy; |
192 | struct tca_apb *ta; |
193 | int i; |
194 | |
195 | ta = devm_kzalloc(dev, size: sizeof(*ta), GFP_KERNEL); |
196 | if (!ta) |
197 | return -ENOMEM; |
198 | |
199 | platform_set_drvdata(pdev, data: ta); |
200 | INIT_WORK(&ta->wk, tca_work); |
201 | |
202 | phy = &ta->phy; |
203 | phy->dev = dev; |
204 | phy->label = dev_name(dev); |
205 | phy->type = USB_PHY_TYPE_USB3; |
206 | phy->init = phy_init; |
207 | phy->shutdown = phy_shutdown; |
208 | phy->set_vbus = phy_set_vbus; |
209 | phy->id_nb.notifier_call = id_notifier; |
210 | phy->vbus_nb.notifier_call = vbus_notifier; |
211 | |
212 | phy->io_priv = devm_platform_ioremap_resource(pdev, index: 0); |
213 | if (IS_ERR(ptr: phy->io_priv)) |
214 | return PTR_ERR(ptr: phy->io_priv); |
215 | |
216 | ta->vbus = devm_regulator_get(dev, id: "vbus" ); |
217 | if (IS_ERR(ptr: ta->vbus)) |
218 | return PTR_ERR(ptr: ta->vbus); |
219 | |
220 | for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) { |
221 | resets[i] = devm_reset_control_get_exclusive(dev, id: CTL_RESETS[i]); |
222 | if (IS_ERR(ptr: resets[i])) { |
223 | dev_err(dev, "%s reset not found\n" , CTL_RESETS[i]); |
224 | return PTR_ERR(ptr: resets[i]); |
225 | } |
226 | } |
227 | |
228 | for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) { |
229 | ta->resets[i] = devm_reset_control_get_exclusive(dev, id: PHY_RESETS[i]); |
230 | if (IS_ERR(ptr: ta->resets[i])) { |
231 | dev_err(dev, "%s reset not found\n" , PHY_RESETS[i]); |
232 | return PTR_ERR(ptr: ta->resets[i]); |
233 | } |
234 | } |
235 | |
236 | for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) |
237 | reset_control_assert(rstc: resets[i]); |
238 | |
239 | for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) |
240 | reset_control_assert(rstc: ta->resets[i]); |
241 | /* |
242 | * Out-of-band reset of the controller after PHY reset will cause |
243 | * controller malfunctioning, so we should use in-band controller |
244 | * reset only and leave the controller de-asserted here. |
245 | */ |
246 | for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) |
247 | reset_control_deassert(rstc: resets[i]); |
248 | |
249 | /* Need to wait at least 20us after de-assert the controller */ |
250 | usleep_range(min: 20, max: 100); |
251 | |
252 | return usb_add_phy_dev(phy); |
253 | } |
254 | |
255 | static void phy_remove(struct platform_device *pdev) |
256 | { |
257 | struct tca_apb *ta = platform_get_drvdata(pdev); |
258 | |
259 | usb_remove_phy(&ta->phy); |
260 | } |
261 | |
262 | static const struct of_device_id intel_usb_phy_dt_ids[] = { |
263 | { .compatible = "intel,lgm-usb-phy" }, |
264 | { } |
265 | }; |
266 | MODULE_DEVICE_TABLE(of, intel_usb_phy_dt_ids); |
267 | |
268 | static struct platform_driver lgm_phy_driver = { |
269 | .driver = { |
270 | .name = "lgm-usb-phy" , |
271 | .of_match_table = intel_usb_phy_dt_ids, |
272 | }, |
273 | .probe = phy_probe, |
274 | .remove_new = phy_remove, |
275 | }; |
276 | |
277 | module_platform_driver(lgm_phy_driver); |
278 | |
279 | MODULE_DESCRIPTION("Intel LGM USB PHY driver" ); |
280 | MODULE_AUTHOR("Li Yin <yin1.li@intel.com>" ); |
281 | MODULE_AUTHOR("Vadivel Murugan R <vadivel.muruganx.ramuthevar@linux.intel.com>" ); |
282 | MODULE_LICENSE("GPL v2" ); |
283 | |