Merge tag 'trace-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
[linux/fpc-iii.git] / drivers / usb / mtu3 / mtu3_dr.c
blob04f666e85731226d35fef1e1aea1af56c86d81cc
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * mtu3_dr.c - dual role switch and host glue layer
5 * Copyright (C) 2016 MediaTek Inc.
7 * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
8 */
10 #include <linux/usb/role.h>
12 #include "mtu3.h"
13 #include "mtu3_dr.h"
14 #include "mtu3_debug.h"
16 #define USB2_PORT 2
17 #define USB3_PORT 3
19 enum mtu3_vbus_id_state {
20 MTU3_ID_FLOAT = 1,
21 MTU3_ID_GROUND,
22 MTU3_VBUS_OFF,
23 MTU3_VBUS_VALID,
26 static char *mailbox_state_string(enum mtu3_vbus_id_state state)
28 switch (state) {
29 case MTU3_ID_FLOAT:
30 return "ID_FLOAT";
31 case MTU3_ID_GROUND:
32 return "ID_GROUND";
33 case MTU3_VBUS_OFF:
34 return "VBUS_OFF";
35 case MTU3_VBUS_VALID:
36 return "VBUS_VALID";
37 default:
38 return "UNKNOWN";
42 static void toggle_opstate(struct ssusb_mtk *ssusb)
44 if (!ssusb->otg_switch.is_u3_drd) {
45 mtu3_setbits(ssusb->mac_base, U3D_DEVICE_CONTROL, DC_SESSION);
46 mtu3_setbits(ssusb->mac_base, U3D_POWER_MANAGEMENT, SOFT_CONN);
50 /* only port0 supports dual-role mode */
51 static int ssusb_port0_switch(struct ssusb_mtk *ssusb,
52 int version, bool tohost)
54 void __iomem *ibase = ssusb->ippc_base;
55 u32 value;
57 dev_dbg(ssusb->dev, "%s (switch u%d port0 to %s)\n", __func__,
58 version, tohost ? "host" : "device");
60 if (version == USB2_PORT) {
61 /* 1. power off and disable u2 port0 */
62 value = mtu3_readl(ibase, SSUSB_U2_CTRL(0));
63 value |= SSUSB_U2_PORT_PDN | SSUSB_U2_PORT_DIS;
64 mtu3_writel(ibase, SSUSB_U2_CTRL(0), value);
66 /* 2. power on, enable u2 port0 and select its mode */
67 value = mtu3_readl(ibase, SSUSB_U2_CTRL(0));
68 value &= ~(SSUSB_U2_PORT_PDN | SSUSB_U2_PORT_DIS);
69 value = tohost ? (value | SSUSB_U2_PORT_HOST_SEL) :
70 (value & (~SSUSB_U2_PORT_HOST_SEL));
71 mtu3_writel(ibase, SSUSB_U2_CTRL(0), value);
72 } else {
73 /* 1. power off and disable u3 port0 */
74 value = mtu3_readl(ibase, SSUSB_U3_CTRL(0));
75 value |= SSUSB_U3_PORT_PDN | SSUSB_U3_PORT_DIS;
76 mtu3_writel(ibase, SSUSB_U3_CTRL(0), value);
78 /* 2. power on, enable u3 port0 and select its mode */
79 value = mtu3_readl(ibase, SSUSB_U3_CTRL(0));
80 value &= ~(SSUSB_U3_PORT_PDN | SSUSB_U3_PORT_DIS);
81 value = tohost ? (value | SSUSB_U3_PORT_HOST_SEL) :
82 (value & (~SSUSB_U3_PORT_HOST_SEL));
83 mtu3_writel(ibase, SSUSB_U3_CTRL(0), value);
86 return 0;
89 static void switch_port_to_host(struct ssusb_mtk *ssusb)
91 u32 check_clk = 0;
93 dev_dbg(ssusb->dev, "%s\n", __func__);
95 ssusb_port0_switch(ssusb, USB2_PORT, true);
97 if (ssusb->otg_switch.is_u3_drd) {
98 ssusb_port0_switch(ssusb, USB3_PORT, true);
99 check_clk = SSUSB_U3_MAC_RST_B_STS;
102 ssusb_check_clocks(ssusb, check_clk);
104 /* after all clocks are stable */
105 toggle_opstate(ssusb);
108 static void switch_port_to_device(struct ssusb_mtk *ssusb)
110 u32 check_clk = 0;
112 dev_dbg(ssusb->dev, "%s\n", __func__);
114 ssusb_port0_switch(ssusb, USB2_PORT, false);
116 if (ssusb->otg_switch.is_u3_drd) {
117 ssusb_port0_switch(ssusb, USB3_PORT, false);
118 check_clk = SSUSB_U3_MAC_RST_B_STS;
121 ssusb_check_clocks(ssusb, check_clk);
124 int ssusb_set_vbus(struct otg_switch_mtk *otg_sx, int is_on)
126 struct ssusb_mtk *ssusb =
127 container_of(otg_sx, struct ssusb_mtk, otg_switch);
128 struct regulator *vbus = otg_sx->vbus;
129 int ret;
131 /* vbus is optional */
132 if (!vbus)
133 return 0;
135 dev_dbg(ssusb->dev, "%s: turn %s\n", __func__, is_on ? "on" : "off");
137 if (is_on) {
138 ret = regulator_enable(vbus);
139 if (ret) {
140 dev_err(ssusb->dev, "vbus regulator enable failed\n");
141 return ret;
143 } else {
144 regulator_disable(vbus);
147 return 0;
151 * switch to host: -> MTU3_VBUS_OFF --> MTU3_ID_GROUND
152 * switch to device: -> MTU3_ID_FLOAT --> MTU3_VBUS_VALID
154 static void ssusb_set_mailbox(struct otg_switch_mtk *otg_sx,
155 enum mtu3_vbus_id_state status)
157 struct ssusb_mtk *ssusb =
158 container_of(otg_sx, struct ssusb_mtk, otg_switch);
159 struct mtu3 *mtu = ssusb->u3d;
161 dev_dbg(ssusb->dev, "mailbox %s\n", mailbox_state_string(status));
162 mtu3_dbg_trace(ssusb->dev, "mailbox %s", mailbox_state_string(status));
164 switch (status) {
165 case MTU3_ID_GROUND:
166 switch_port_to_host(ssusb);
167 ssusb_set_vbus(otg_sx, 1);
168 ssusb->is_host = true;
169 break;
170 case MTU3_ID_FLOAT:
171 ssusb->is_host = false;
172 ssusb_set_vbus(otg_sx, 0);
173 switch_port_to_device(ssusb);
174 break;
175 case MTU3_VBUS_OFF:
176 mtu3_stop(mtu);
177 pm_relax(ssusb->dev);
178 break;
179 case MTU3_VBUS_VALID:
180 /* avoid suspend when works as device */
181 pm_stay_awake(ssusb->dev);
182 mtu3_start(mtu);
183 break;
184 default:
185 dev_err(ssusb->dev, "invalid state\n");
189 static void ssusb_id_work(struct work_struct *work)
191 struct otg_switch_mtk *otg_sx =
192 container_of(work, struct otg_switch_mtk, id_work);
194 if (otg_sx->id_event)
195 ssusb_set_mailbox(otg_sx, MTU3_ID_GROUND);
196 else
197 ssusb_set_mailbox(otg_sx, MTU3_ID_FLOAT);
200 static void ssusb_vbus_work(struct work_struct *work)
202 struct otg_switch_mtk *otg_sx =
203 container_of(work, struct otg_switch_mtk, vbus_work);
205 if (otg_sx->vbus_event)
206 ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID);
207 else
208 ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF);
212 * @ssusb_id_notifier is called in atomic context, but @ssusb_set_mailbox
213 * may sleep, so use work queue here
215 static int ssusb_id_notifier(struct notifier_block *nb,
216 unsigned long event, void *ptr)
218 struct otg_switch_mtk *otg_sx =
219 container_of(nb, struct otg_switch_mtk, id_nb);
221 otg_sx->id_event = event;
222 schedule_work(&otg_sx->id_work);
224 return NOTIFY_DONE;
227 static int ssusb_vbus_notifier(struct notifier_block *nb,
228 unsigned long event, void *ptr)
230 struct otg_switch_mtk *otg_sx =
231 container_of(nb, struct otg_switch_mtk, vbus_nb);
233 otg_sx->vbus_event = event;
234 schedule_work(&otg_sx->vbus_work);
236 return NOTIFY_DONE;
239 static int ssusb_extcon_register(struct otg_switch_mtk *otg_sx)
241 struct ssusb_mtk *ssusb =
242 container_of(otg_sx, struct ssusb_mtk, otg_switch);
243 struct extcon_dev *edev = otg_sx->edev;
244 int ret;
246 /* extcon is optional */
247 if (!edev)
248 return 0;
250 otg_sx->vbus_nb.notifier_call = ssusb_vbus_notifier;
251 ret = devm_extcon_register_notifier(ssusb->dev, edev, EXTCON_USB,
252 &otg_sx->vbus_nb);
253 if (ret < 0) {
254 dev_err(ssusb->dev, "failed to register notifier for USB\n");
255 return ret;
258 otg_sx->id_nb.notifier_call = ssusb_id_notifier;
259 ret = devm_extcon_register_notifier(ssusb->dev, edev, EXTCON_USB_HOST,
260 &otg_sx->id_nb);
261 if (ret < 0) {
262 dev_err(ssusb->dev, "failed to register notifier for USB-HOST\n");
263 return ret;
266 dev_dbg(ssusb->dev, "EXTCON_USB: %d, EXTCON_USB_HOST: %d\n",
267 extcon_get_state(edev, EXTCON_USB),
268 extcon_get_state(edev, EXTCON_USB_HOST));
270 /* default as host, switch to device mode if needed */
271 if (extcon_get_state(edev, EXTCON_USB_HOST) == false)
272 ssusb_set_mailbox(otg_sx, MTU3_ID_FLOAT);
273 if (extcon_get_state(edev, EXTCON_USB) == true)
274 ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID);
276 return 0;
280 * We provide an interface via debugfs to switch between host and device modes
281 * depending on user input.
282 * This is useful in special cases, such as uses TYPE-A receptacle but also
283 * wants to support dual-role mode.
285 void ssusb_mode_switch(struct ssusb_mtk *ssusb, int to_host)
287 struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
289 if (to_host) {
290 ssusb_set_force_mode(ssusb, MTU3_DR_FORCE_HOST);
291 ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF);
292 ssusb_set_mailbox(otg_sx, MTU3_ID_GROUND);
293 } else {
294 ssusb_set_force_mode(ssusb, MTU3_DR_FORCE_DEVICE);
295 ssusb_set_mailbox(otg_sx, MTU3_ID_FLOAT);
296 ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID);
300 void ssusb_set_force_mode(struct ssusb_mtk *ssusb,
301 enum mtu3_dr_force_mode mode)
303 u32 value;
305 value = mtu3_readl(ssusb->ippc_base, SSUSB_U2_CTRL(0));
306 switch (mode) {
307 case MTU3_DR_FORCE_DEVICE:
308 value |= SSUSB_U2_PORT_FORCE_IDDIG | SSUSB_U2_PORT_RG_IDDIG;
309 break;
310 case MTU3_DR_FORCE_HOST:
311 value |= SSUSB_U2_PORT_FORCE_IDDIG;
312 value &= ~SSUSB_U2_PORT_RG_IDDIG;
313 break;
314 case MTU3_DR_FORCE_NONE:
315 value &= ~(SSUSB_U2_PORT_FORCE_IDDIG | SSUSB_U2_PORT_RG_IDDIG);
316 break;
317 default:
318 return;
320 mtu3_writel(ssusb->ippc_base, SSUSB_U2_CTRL(0), value);
323 static int ssusb_role_sw_set(struct usb_role_switch *sw, enum usb_role role)
325 struct ssusb_mtk *ssusb = usb_role_switch_get_drvdata(sw);
326 bool to_host = false;
328 if (role == USB_ROLE_HOST)
329 to_host = true;
331 if (to_host ^ ssusb->is_host)
332 ssusb_mode_switch(ssusb, to_host);
334 return 0;
337 static enum usb_role ssusb_role_sw_get(struct usb_role_switch *sw)
339 struct ssusb_mtk *ssusb = usb_role_switch_get_drvdata(sw);
340 enum usb_role role;
342 role = ssusb->is_host ? USB_ROLE_HOST : USB_ROLE_DEVICE;
344 return role;
347 static int ssusb_role_sw_register(struct otg_switch_mtk *otg_sx)
349 struct usb_role_switch_desc role_sx_desc = { 0 };
350 struct ssusb_mtk *ssusb =
351 container_of(otg_sx, struct ssusb_mtk, otg_switch);
353 if (!otg_sx->role_sw_used)
354 return 0;
356 role_sx_desc.set = ssusb_role_sw_set;
357 role_sx_desc.get = ssusb_role_sw_get;
358 role_sx_desc.fwnode = dev_fwnode(ssusb->dev);
359 role_sx_desc.driver_data = ssusb;
360 otg_sx->role_sw = usb_role_switch_register(ssusb->dev, &role_sx_desc);
362 return PTR_ERR_OR_ZERO(otg_sx->role_sw);
365 int ssusb_otg_switch_init(struct ssusb_mtk *ssusb)
367 struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
368 int ret = 0;
370 INIT_WORK(&otg_sx->id_work, ssusb_id_work);
371 INIT_WORK(&otg_sx->vbus_work, ssusb_vbus_work);
373 if (otg_sx->manual_drd_enabled)
374 ssusb_dr_debugfs_init(ssusb);
375 else if (otg_sx->role_sw_used)
376 ret = ssusb_role_sw_register(otg_sx);
377 else
378 ret = ssusb_extcon_register(otg_sx);
380 return ret;
383 void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb)
385 struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
387 cancel_work_sync(&otg_sx->id_work);
388 cancel_work_sync(&otg_sx->vbus_work);
389 usb_role_switch_unregister(otg_sx->role_sw);