1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (C) 2017 Broadcom
3
4 #include <linux/delay.h>
5 #include <linux/extcon-provider.h>
6 #include <linux/gpio.h>
7 #include <linux/gpio/consumer.h>
8 #include <linux/init.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/irq.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/phy/phy.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/slab.h>
21 #include <linux/workqueue.h>
22
23 #define ICFG_DRD_AFE 0x0
24 #define ICFG_MISC_STAT 0x18
25 #define ICFG_DRD_P0CTL 0x1C
26 #define ICFG_STRAP_CTRL 0x20
27 #define ICFG_FSM_CTRL 0x24
28
29 #define ICFG_DEV_BIT BIT(2)
30 #define IDM_RST_BIT BIT(0)
31 #define AFE_CORERDY_VDDC BIT(18)
32 #define PHY_PLL_RESETB BIT(15)
33 #define PHY_RESETB BIT(14)
34 #define PHY_PLL_LOCK BIT(0)
35
36 #define DRD_DEV_MODE BIT(20)
37 #define OHCI_OVRCUR_POL BIT(11)
38 #define ICFG_OFF_MODE BIT(6)
39 #define PLL_LOCK_RETRY 1000
40
41 #define EVT_DEVICE 0
42 #define EVT_HOST 1
43
44 #define DRD_HOST_MODE (BIT(2) | BIT(3))
45 #define DRD_DEVICE_MODE (BIT(4) | BIT(5))
46 #define DRD_HOST_VAL 0x803
47 #define DRD_DEV_VAL 0x807
48 #define GPIO_DELAY 20
49
50 struct ns2_phy_data;
51 struct ns2_phy_driver {
52 void __iomem *icfgdrd_regs;
53 void __iomem *idmdrd_rst_ctrl;
54 void __iomem *crmu_usb2_ctrl;
55 void __iomem *usb2h_strap_reg;
56 struct ns2_phy_data *data;
57 struct extcon_dev *edev;
58 struct gpio_desc *vbus_gpiod;
59 struct gpio_desc *id_gpiod;
60 int id_irq;
61 int vbus_irq;
62 unsigned long debounce_jiffies;
63 struct delayed_work wq_extcon;
64 };
65
66 struct ns2_phy_data {
67 struct ns2_phy_driver *driver;
68 struct phy *phy;
69 int new_state;
70 };
71
72 static const unsigned int usb_extcon_cable[] = {
73 EXTCON_USB,
74 EXTCON_USB_HOST,
75 EXTCON_NONE,
76 };
77
pll_lock_stat(u32 usb_reg,int reg_mask,struct ns2_phy_driver * driver)78 static inline int pll_lock_stat(u32 usb_reg, int reg_mask,
79 struct ns2_phy_driver *driver)
80 {
81 u32 val;
82
83 return readl_poll_timeout_atomic(driver->icfgdrd_regs + usb_reg,
84 val, (val & reg_mask), 1,
85 PLL_LOCK_RETRY);
86 }
87
ns2_drd_phy_init(struct phy * phy)88 static int ns2_drd_phy_init(struct phy *phy)
89 {
90 struct ns2_phy_data *data = phy_get_drvdata(phy);
91 struct ns2_phy_driver *driver = data->driver;
92 u32 val;
93
94 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
95
96 if (data->new_state == EVT_HOST) {
97 val &= ~DRD_DEVICE_MODE;
98 val |= DRD_HOST_MODE;
99 } else {
100 val &= ~DRD_HOST_MODE;
101 val |= DRD_DEVICE_MODE;
102 }
103 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
104
105 return 0;
106 }
107
ns2_drd_phy_poweroff(struct phy * phy)108 static int ns2_drd_phy_poweroff(struct phy *phy)
109 {
110 struct ns2_phy_data *data = phy_get_drvdata(phy);
111 struct ns2_phy_driver *driver = data->driver;
112 u32 val;
113
114 val = readl(driver->crmu_usb2_ctrl);
115 val &= ~AFE_CORERDY_VDDC;
116 writel(val, driver->crmu_usb2_ctrl);
117
118 val = readl(driver->crmu_usb2_ctrl);
119 val &= ~DRD_DEV_MODE;
120 writel(val, driver->crmu_usb2_ctrl);
121
122 /* Disable Host and Device Mode */
123 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
124 val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE | ICFG_OFF_MODE);
125 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
126
127 return 0;
128 }
129
ns2_drd_phy_poweron(struct phy * phy)130 static int ns2_drd_phy_poweron(struct phy *phy)
131 {
132 struct ns2_phy_data *data = phy_get_drvdata(phy);
133 struct ns2_phy_driver *driver = data->driver;
134 u32 extcon_event = data->new_state;
135 int ret;
136 u32 val;
137
138 if (extcon_event == EVT_DEVICE) {
139 writel(DRD_DEV_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
140
141 val = readl(driver->idmdrd_rst_ctrl);
142 val &= ~IDM_RST_BIT;
143 writel(val, driver->idmdrd_rst_ctrl);
144
145 val = readl(driver->crmu_usb2_ctrl);
146 val |= (AFE_CORERDY_VDDC | DRD_DEV_MODE);
147 writel(val, driver->crmu_usb2_ctrl);
148
149 /* Bring PHY and PHY_PLL out of Reset */
150 val = readl(driver->crmu_usb2_ctrl);
151 val |= (PHY_PLL_RESETB | PHY_RESETB);
152 writel(val, driver->crmu_usb2_ctrl);
153
154 ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
155 if (ret < 0) {
156 dev_err(&phy->dev, "Phy PLL lock failed\n");
157 return ret;
158 }
159 } else {
160 writel(DRD_HOST_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
161
162 val = readl(driver->crmu_usb2_ctrl);
163 val |= AFE_CORERDY_VDDC;
164 writel(val, driver->crmu_usb2_ctrl);
165
166 ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
167 if (ret < 0) {
168 dev_err(&phy->dev, "Phy PLL lock failed\n");
169 return ret;
170 }
171
172 val = readl(driver->idmdrd_rst_ctrl);
173 val &= ~IDM_RST_BIT;
174 writel(val, driver->idmdrd_rst_ctrl);
175
176 /* port over current Polarity */
177 val = readl(driver->usb2h_strap_reg);
178 val |= OHCI_OVRCUR_POL;
179 writel(val, driver->usb2h_strap_reg);
180 }
181
182 return 0;
183 }
184
connect_change(struct ns2_phy_driver * driver)185 static void connect_change(struct ns2_phy_driver *driver)
186 {
187 u32 extcon_event;
188 u32 val;
189
190 extcon_event = driver->data->new_state;
191 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
192
193 switch (extcon_event) {
194 case EVT_DEVICE:
195 val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
196 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
197
198 val = (val & ~DRD_HOST_MODE) | DRD_DEVICE_MODE;
199 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
200
201 val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
202 val |= ICFG_DEV_BIT;
203 writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
204 break;
205
206 case EVT_HOST:
207 val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
208 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
209
210 val = (val & ~DRD_DEVICE_MODE) | DRD_HOST_MODE;
211 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);
212
213 val = readl(driver->usb2h_strap_reg);
214 val |= OHCI_OVRCUR_POL;
215 writel(val, driver->usb2h_strap_reg);
216
217 val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
218 val &= ~ICFG_DEV_BIT;
219 writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
220 break;
221
222 default:
223 pr_err("Invalid extcon event\n");
224 break;
225 }
226 }
227
extcon_work(struct work_struct * work)228 static void extcon_work(struct work_struct *work)
229 {
230 struct ns2_phy_driver *driver;
231 int vbus;
232 int id;
233
234 driver = container_of(to_delayed_work(work),
235 struct ns2_phy_driver, wq_extcon);
236
237 id = gpiod_get_value_cansleep(driver->id_gpiod);
238 vbus = gpiod_get_value_cansleep(driver->vbus_gpiod);
239
240 if (!id && vbus) { /* Host connected */
241 extcon_set_state_sync(driver->edev, EXTCON_USB_HOST, true);
242 pr_debug("Host cable connected\n");
243 driver->data->new_state = EVT_HOST;
244 connect_change(driver);
245 } else if (id && !vbus) { /* Disconnected */
246 extcon_set_state_sync(driver->edev, EXTCON_USB_HOST, false);
247 extcon_set_state_sync(driver->edev, EXTCON_USB, false);
248 pr_debug("Cable disconnected\n");
249 } else if (id && vbus) { /* Device connected */
250 extcon_set_state_sync(driver->edev, EXTCON_USB, true);
251 pr_debug("Device cable connected\n");
252 driver->data->new_state = EVT_DEVICE;
253 connect_change(driver);
254 }
255 }
256
gpio_irq_handler(int irq,void * dev_id)257 static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
258 {
259 struct ns2_phy_driver *driver = dev_id;
260
261 queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
262 driver->debounce_jiffies);
263
264 return IRQ_HANDLED;
265 }
266
267 static const struct phy_ops ops = {
268 .init = ns2_drd_phy_init,
269 .power_on = ns2_drd_phy_poweron,
270 .power_off = ns2_drd_phy_poweroff,
271 .owner = THIS_MODULE,
272 };
273
274 static const struct of_device_id ns2_drd_phy_dt_ids[] = {
275 { .compatible = "brcm,ns2-drd-phy", },
276 { }
277 };
278 MODULE_DEVICE_TABLE(of, ns2_drd_phy_dt_ids);
279
ns2_drd_phy_probe(struct platform_device * pdev)280 static int ns2_drd_phy_probe(struct platform_device *pdev)
281 {
282 struct phy_provider *phy_provider;
283 struct device *dev = &pdev->dev;
284 struct ns2_phy_driver *driver;
285 struct ns2_phy_data *data;
286 int ret;
287 u32 val;
288
289 driver = devm_kzalloc(dev, sizeof(struct ns2_phy_driver),
290 GFP_KERNEL);
291 if (!driver)
292 return -ENOMEM;
293
294 driver->data = devm_kzalloc(dev, sizeof(struct ns2_phy_data),
295 GFP_KERNEL);
296 if (!driver->data)
297 return -ENOMEM;
298
299 driver->icfgdrd_regs = devm_platform_ioremap_resource_byname(pdev, "icfg");
300 if (IS_ERR(driver->icfgdrd_regs))
301 return PTR_ERR(driver->icfgdrd_regs);
302
303 driver->idmdrd_rst_ctrl = devm_platform_ioremap_resource_byname(pdev, "rst-ctrl");
304 if (IS_ERR(driver->idmdrd_rst_ctrl))
305 return PTR_ERR(driver->idmdrd_rst_ctrl);
306
307 driver->crmu_usb2_ctrl = devm_platform_ioremap_resource_byname(pdev, "crmu-ctrl");
308 if (IS_ERR(driver->crmu_usb2_ctrl))
309 return PTR_ERR(driver->crmu_usb2_ctrl);
310
311 driver->usb2h_strap_reg = devm_platform_ioremap_resource_byname(pdev, "usb2-strap");
312 if (IS_ERR(driver->usb2h_strap_reg))
313 return PTR_ERR(driver->usb2h_strap_reg);
314
315 /* create extcon */
316 driver->id_gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
317 if (IS_ERR(driver->id_gpiod)) {
318 dev_err(dev, "failed to get ID GPIO\n");
319 return PTR_ERR(driver->id_gpiod);
320 }
321 driver->vbus_gpiod = devm_gpiod_get(&pdev->dev, "vbus", GPIOD_IN);
322 if (IS_ERR(driver->vbus_gpiod)) {
323 dev_err(dev, "failed to get VBUS GPIO\n");
324 return PTR_ERR(driver->vbus_gpiod);
325 }
326
327 driver->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
328 if (IS_ERR(driver->edev)) {
329 dev_err(dev, "failed to allocate extcon device\n");
330 return -ENOMEM;
331 }
332
333 ret = devm_extcon_dev_register(dev, driver->edev);
334 if (ret < 0) {
335 dev_err(dev, "failed to register extcon device\n");
336 return ret;
337 }
338
339 ret = gpiod_set_debounce(driver->id_gpiod, GPIO_DELAY * 1000);
340 if (ret < 0)
341 driver->debounce_jiffies = msecs_to_jiffies(GPIO_DELAY);
342
343 INIT_DELAYED_WORK(&driver->wq_extcon, extcon_work);
344
345 driver->id_irq = gpiod_to_irq(driver->id_gpiod);
346 if (driver->id_irq < 0) {
347 dev_err(dev, "failed to get ID IRQ\n");
348 return driver->id_irq;
349 }
350
351 driver->vbus_irq = gpiod_to_irq(driver->vbus_gpiod);
352 if (driver->vbus_irq < 0) {
353 dev_err(dev, "failed to get ID IRQ\n");
354 return driver->vbus_irq;
355 }
356
357 ret = devm_request_irq(dev, driver->id_irq, gpio_irq_handler,
358 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
359 "usb_id", driver);
360 if (ret < 0) {
361 dev_err(dev, "failed to request handler for ID IRQ\n");
362 return ret;
363 }
364
365 ret = devm_request_irq(dev, driver->vbus_irq, gpio_irq_handler,
366 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
367 "usb_vbus", driver);
368 if (ret < 0) {
369 dev_err(dev, "failed to request handler for VBUS IRQ\n");
370 return ret;
371 }
372
373 dev_set_drvdata(dev, driver);
374
375 /* Shutdown all ports. They can be powered up as required */
376 val = readl(driver->crmu_usb2_ctrl);
377 val &= ~(AFE_CORERDY_VDDC | PHY_RESETB);
378 writel(val, driver->crmu_usb2_ctrl);
379
380 data = driver->data;
381 data->phy = devm_phy_create(dev, dev->of_node, &ops);
382 if (IS_ERR(data->phy)) {
383 dev_err(dev, "Failed to create usb drd phy\n");
384 return PTR_ERR(data->phy);
385 }
386
387 data->driver = driver;
388 phy_set_drvdata(data->phy, data);
389
390 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
391 if (IS_ERR(phy_provider)) {
392 dev_err(dev, "Failed to register as phy provider\n");
393 return PTR_ERR(phy_provider);
394 }
395
396 platform_set_drvdata(pdev, driver);
397
398 dev_info(dev, "Registered NS2 DRD Phy device\n");
399 queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
400 driver->debounce_jiffies);
401
402 return 0;
403 }
404
405 static struct platform_driver ns2_drd_phy_driver = {
406 .probe = ns2_drd_phy_probe,
407 .driver = {
408 .name = "bcm-ns2-usbphy",
409 .of_match_table = of_match_ptr(ns2_drd_phy_dt_ids),
410 },
411 };
412 module_platform_driver(ns2_drd_phy_driver);
413
414 MODULE_ALIAS("platform:bcm-ns2-drd-phy");
415 MODULE_AUTHOR("Broadcom");
416 MODULE_DESCRIPTION("Broadcom NS2 USB2 PHY driver");
417 MODULE_LICENSE("GPL v2");
418