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
50struct ns2_phy_data;
51struct 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
66struct ns2_phy_data {
67	struct ns2_phy_driver *driver;
68	struct phy *phy;
69	int new_state;
70};
71
72static const unsigned int usb_extcon_cable[] = {
73	EXTCON_USB,
74	EXTCON_USB_HOST,
75	EXTCON_NONE,
76};
77
78static 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
88static 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
108static 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
130static 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
185static 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
228static 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
257static 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
267static 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
274static const struct of_device_id ns2_drd_phy_dt_ids[] = {
275	{ .compatible = "brcm,ns2-drd-phy", },
276	{ }
277};
278MODULE_DEVICE_TABLE(of, ns2_drd_phy_dt_ids);
279
280static 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
405static 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};
412module_platform_driver(ns2_drd_phy_driver);
413
414MODULE_ALIAS("platform:bcm-ns2-drd-phy");
415MODULE_AUTHOR("Broadcom");
416MODULE_DESCRIPTION("Broadcom NS2 USB2 PHY driver");
417MODULE_LICENSE("GPL v2");
418