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v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Cadence USBSS DRD Driver.
  4 *
  5 * Copyright (C) 2018-2019 Cadence.
  6 * Copyright (C) 2019 Texas Instruments
  7 *
  8 * Author: Pawel Laszczak <pawell@cadence.com>
  9 *         Roger Quadros <rogerq@ti.com>
 10 *
 11 *
 12 */
 13#include <linux/kernel.h>
 14#include <linux/interrupt.h>
 15#include <linux/delay.h>
 16#include <linux/iopoll.h>
 17#include <linux/usb/otg.h>
 18
 19#include "gadget.h"
 20#include "drd.h"
 21#include "core.h"
 22
 23/**
 24 * cdns3_set_mode - change mode of OTG Core
 25 * @cdns: pointer to context structure
 26 * @mode: selected mode from cdns_role
 27 *
 28 * Returns 0 on success otherwise negative errno
 29 */
 30int cdns3_set_mode(struct cdns3 *cdns, enum usb_dr_mode mode)
 31{
 
 32	u32 reg;
 33
 34	switch (mode) {
 35	case USB_DR_MODE_PERIPHERAL:
 36		break;
 37	case USB_DR_MODE_HOST:
 38		break;
 39	case USB_DR_MODE_OTG:
 40		dev_dbg(cdns->dev, "Set controller to OTG mode\n");
 41		if (cdns->version == CDNS3_CONTROLLER_V1) {
 42			reg = readl(&cdns->otg_v1_regs->override);
 43			reg |= OVERRIDE_IDPULLUP;
 44			writel(reg, &cdns->otg_v1_regs->override);
 45		} else {
 46			reg = readl(&cdns->otg_v0_regs->ctrl1);
 47			reg |= OVERRIDE_IDPULLUP_V0;
 48			writel(reg, &cdns->otg_v0_regs->ctrl1);
 49		}
 50
 51		/*
 52		 * Hardware specification says: "ID_VALUE must be valid within
 53		 * 50ms after idpullup is set to '1" so driver must wait
 54		 * 50ms before reading this pin.
 55		 */
 56		usleep_range(50000, 60000);
 57		break;
 58	default:
 59		dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
 60		return -EINVAL;
 61	}
 62
 63	return 0;
 64}
 65
 66int cdns3_get_id(struct cdns3 *cdns)
 67{
 68	int id;
 69
 70	id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
 71	dev_dbg(cdns->dev, "OTG ID: %d", id);
 72
 73	return id;
 74}
 75
 76int cdns3_get_vbus(struct cdns3 *cdns)
 77{
 78	int vbus;
 79
 80	vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
 81	dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
 82
 83	return vbus;
 84}
 85
 86bool cdns3_is_host(struct cdns3 *cdns)
 87{
 88	if (cdns->dr_mode == USB_DR_MODE_HOST)
 89		return true;
 90	else if (cdns3_get_id(cdns) == CDNS3_ID_HOST)
 91		return true;
 92
 93	return false;
 94}
 95
 96bool cdns3_is_device(struct cdns3 *cdns)
 97{
 98	if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
 99		return true;
100	else if (cdns->dr_mode == USB_DR_MODE_OTG)
101		if (cdns3_get_id(cdns) == CDNS3_ID_PERIPHERAL)
102			return true;
103
104	return false;
105}
106
107/**
108 * cdns3_otg_disable_irq - Disable all OTG interrupts
109 * @cdns: Pointer to controller context structure
110 */
111static void cdns3_otg_disable_irq(struct cdns3 *cdns)
112{
113	writel(0, &cdns->otg_regs->ien);
114}
115
116/**
117 * cdns3_otg_enable_irq - enable id and sess_valid interrupts
118 * @cdns: Pointer to controller context structure
119 */
120static void cdns3_otg_enable_irq(struct cdns3 *cdns)
121{
122	writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT |
123	       OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_regs->ien);
124}
125
126/**
127 * cdns3_drd_host_on - start host.
128 * @cdns: Pointer to controller context structure.
 
129 *
130 * Returns 0 on success otherwise negative errno.
131 */
132int cdns3_drd_host_on(struct cdns3 *cdns)
133{
134	u32 val;
135	int ret;
136
137	/* Enable host mode. */
138	writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS,
139	       &cdns->otg_regs->cmd);
140
141	dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
142	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
143					val & OTGSTS_XHCI_READY, 1, 100000);
144
145	if (ret)
146		dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
147
148	return ret;
149}
 
150
151/**
152 * cdns3_drd_host_off - stop host.
153 * @cdns: Pointer to controller context structure.
154 */
155void cdns3_drd_host_off(struct cdns3 *cdns)
156{
157	u32 val;
 
 
 
 
 
 
 
 
 
 
158
159	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
160	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
161	       &cdns->otg_regs->cmd);
162
163	/* Waiting till H_IDLE state.*/
164	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
165				  !(val & OTGSTATE_HOST_STATE_MASK),
166				  1, 2000000);
167}
168
169/**
170 * cdns3_drd_gadget_on - start gadget.
171 * @cdns: Pointer to controller context structure.
 
172 *
173 * Returns 0 on success otherwise negative errno
174 */
175int cdns3_drd_gadget_on(struct cdns3 *cdns)
176{
177	int ret, val;
178	u32 reg = OTGCMD_OTG_DIS;
179
180	/* switch OTG core */
181	writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
 
182
183	dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
184
185	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
186					val & OTGSTS_DEV_READY,
187					1, 100000);
188	if (ret) {
189		dev_err(cdns->dev, "timeout waiting for dev_ready\n");
190		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
191	}
192
193	return 0;
194}
195
196/**
197 * cdns3_drd_gadget_off - stop gadget.
198 * @cdns: Pointer to controller context structure.
199 */
200void cdns3_drd_gadget_off(struct cdns3 *cdns)
201{
202	u32 val;
203
204	/*
205	 * Driver should wait at least 10us after disabling Device
206	 * before turning-off Device (DEV_BUS_DROP).
207	 */
208	usleep_range(20, 30);
209	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
210	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
211	       &cdns->otg_regs->cmd);
212	/* Waiting till DEV_IDLE state.*/
213	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
214				  !(val & OTGSTATE_DEV_STATE_MASK),
215				  1, 2000000);
216}
217
218/**
219 * cdns3_init_otg_mode - initialize drd controller
220 * @cdns: Pointer to controller context structure
221 *
222 * Returns 0 on success otherwise negative errno
223 */
224static int cdns3_init_otg_mode(struct cdns3 *cdns)
225{
226	int ret;
227
228	cdns3_otg_disable_irq(cdns);
229	/* clear all interrupts */
230	writel(~0, &cdns->otg_regs->ivect);
231
232	ret = cdns3_set_mode(cdns, USB_DR_MODE_OTG);
233	if (ret)
234		return ret;
235
236	cdns3_otg_enable_irq(cdns);
237
238	return 0;
239}
240
241/**
242 * cdns3_drd_update_mode - initialize mode of operation
243 * @cdns: Pointer to controller context structure
244 *
245 * Returns 0 on success otherwise negative errno
246 */
247int cdns3_drd_update_mode(struct cdns3 *cdns)
248{
249	int ret;
250
251	switch (cdns->dr_mode) {
252	case USB_DR_MODE_PERIPHERAL:
253		ret = cdns3_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
254		break;
255	case USB_DR_MODE_HOST:
256		ret = cdns3_set_mode(cdns, USB_DR_MODE_HOST);
257		break;
258	case USB_DR_MODE_OTG:
259		ret = cdns3_init_otg_mode(cdns);
260		break;
261	default:
262		dev_err(cdns->dev, "Unsupported mode of operation %d\n",
263			cdns->dr_mode);
264		return -EINVAL;
265	}
266
267	return ret;
268}
269
270static irqreturn_t cdns3_drd_thread_irq(int irq, void *data)
271{
272	struct cdns3 *cdns = data;
273
274	cdns3_hw_role_switch(cdns);
275
276	return IRQ_HANDLED;
277}
278
279/**
280 * cdns3_drd_irq - interrupt handler for OTG events
281 *
282 * @irq: irq number for cdns3 core device
283 * @data: structure of cdns3
284 *
285 * Returns IRQ_HANDLED or IRQ_NONE
286 */
287static irqreturn_t cdns3_drd_irq(int irq, void *data)
288{
289	irqreturn_t ret = IRQ_NONE;
290	struct cdns3 *cdns = data;
291	u32 reg;
292
293	if (cdns->dr_mode != USB_DR_MODE_OTG)
294		return IRQ_NONE;
295
296	reg = readl(&cdns->otg_regs->ivect);
297
298	if (!reg)
299		return IRQ_NONE;
300
301	if (reg & OTGIEN_ID_CHANGE_INT) {
302		dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n",
303			cdns3_get_id(cdns));
304
305		ret = IRQ_WAKE_THREAD;
306	}
307
308	if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) {
309		dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n",
310			cdns3_get_vbus(cdns));
311
312		ret = IRQ_WAKE_THREAD;
313	}
314
315	writel(~0, &cdns->otg_regs->ivect);
316	return ret;
317}
318
319int cdns3_drd_init(struct cdns3 *cdns)
320{
321	void __iomem *regs;
 
322	u32 state;
323	int ret;
324
325	regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res);
326	if (IS_ERR(regs))
327		return PTR_ERR(regs);
328
329	/* Detection of DRD version. Controller has been released
330	 * in two versions. Both are similar, but they have same changes
331	 * in register maps.
332	 * The first register in old version is command register and it's read
333	 * only, so driver should read 0 from it. On the other hand, in v1
334	 * the first register contains device ID number which is not set to 0.
335	 * Driver uses this fact to detect the proper version of
336	 * controller.
337	 */
338	cdns->otg_v0_regs = regs;
339	if (!readl(&cdns->otg_v0_regs->cmd)) {
340		cdns->version  = CDNS3_CONTROLLER_V0;
341		cdns->otg_v1_regs = NULL;
342		cdns->otg_regs = regs;
343		writel(1, &cdns->otg_v0_regs->simulate);
344		dev_dbg(cdns->dev, "DRD version v0 (%08x)\n",
345			 readl(&cdns->otg_v0_regs->version));
346	} else {
347		cdns->otg_v0_regs = NULL;
348		cdns->otg_v1_regs = regs;
349		cdns->otg_regs = (void *)&cdns->otg_v1_regs->cmd;
350		cdns->version  = CDNS3_CONTROLLER_V1;
351		writel(1, &cdns->otg_v1_regs->simulate);
352		dev_dbg(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
353			 readl(&cdns->otg_v1_regs->did),
354			 readl(&cdns->otg_v1_regs->rid));
355	}
356
357	state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
358
359	/* Update dr_mode according to STRAP configuration. */
360	cdns->dr_mode = USB_DR_MODE_OTG;
361	if (state == OTGSTS_STRAP_HOST) {
362		dev_dbg(cdns->dev, "Controller strapped to HOST\n");
363		cdns->dr_mode = USB_DR_MODE_HOST;
364	} else if (state == OTGSTS_STRAP_GADGET) {
365		dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
366		cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
367	}
368
369	ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq,
370					cdns3_drd_irq,
371					cdns3_drd_thread_irq,
372					IRQF_SHARED,
373					dev_name(cdns->dev), cdns);
 
374	if (ret) {
375		dev_err(cdns->dev, "couldn't get otg_irq\n");
376		return ret;
377	}
378
379	state = readl(&cdns->otg_regs->sts);
380	if (OTGSTS_OTG_NRDY(state)) {
381		dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
382		return -ENODEV;
383	}
384
385	return 0;
386}
387
388int cdns3_drd_exit(struct cdns3 *cdns)
389{
390	cdns3_otg_disable_irq(cdns);
391	return 0;
392}
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Cadence USBSS DRD Driver.
  4 *
  5 * Copyright (C) 2018-2019 Cadence.
  6 * Copyright (C) 2019 Texas Instruments
  7 *
  8 * Author: Pawel Laszczak <pawell@cadence.com>
  9 *         Roger Quadros <rogerq@ti.com>
 10 *
 11 *
 12 */
 13#include <linux/kernel.h>
 14#include <linux/interrupt.h>
 15#include <linux/delay.h>
 16#include <linux/iopoll.h>
 17#include <linux/usb/otg.h>
 18
 19#include "gadget.h"
 20#include "drd.h"
 21#include "core.h"
 22
 23/**
 24 * cdns3_set_mode - change mode of OTG Core
 25 * @cdns: pointer to context structure
 26 * @mode: selected mode from cdns_role
 27 *
 28 * Returns 0 on success otherwise negative errno
 29 */
 30int cdns3_set_mode(struct cdns3 *cdns, enum usb_dr_mode mode)
 31{
 32	int ret = 0;
 33	u32 reg;
 34
 35	switch (mode) {
 36	case USB_DR_MODE_PERIPHERAL:
 37		break;
 38	case USB_DR_MODE_HOST:
 39		break;
 40	case USB_DR_MODE_OTG:
 41		dev_dbg(cdns->dev, "Set controller to OTG mode\n");
 42		if (cdns->version == CDNS3_CONTROLLER_V1) {
 43			reg = readl(&cdns->otg_v1_regs->override);
 44			reg |= OVERRIDE_IDPULLUP;
 45			writel(reg, &cdns->otg_v1_regs->override);
 46		} else {
 47			reg = readl(&cdns->otg_v0_regs->ctrl1);
 48			reg |= OVERRIDE_IDPULLUP_V0;
 49			writel(reg, &cdns->otg_v0_regs->ctrl1);
 50		}
 51
 52		/*
 53		 * Hardware specification says: "ID_VALUE must be valid within
 54		 * 50ms after idpullup is set to '1" so driver must wait
 55		 * 50ms before reading this pin.
 56		 */
 57		usleep_range(50000, 60000);
 58		break;
 59	default:
 60		dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
 61		return -EINVAL;
 62	}
 63
 64	return ret;
 65}
 66
 67int cdns3_get_id(struct cdns3 *cdns)
 68{
 69	int id;
 70
 71	id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
 72	dev_dbg(cdns->dev, "OTG ID: %d", id);
 73
 74	return id;
 75}
 76
 77int cdns3_get_vbus(struct cdns3 *cdns)
 78{
 79	int vbus;
 80
 81	vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
 82	dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
 83
 84	return vbus;
 85}
 86
 87int cdns3_is_host(struct cdns3 *cdns)
 88{
 89	if (cdns->dr_mode == USB_DR_MODE_HOST)
 90		return 1;
 91	else if (!cdns3_get_id(cdns))
 92		return 1;
 93
 94	return 0;
 95}
 96
 97int cdns3_is_device(struct cdns3 *cdns)
 98{
 99	if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
100		return 1;
101	else if (cdns->dr_mode == USB_DR_MODE_OTG)
102		if (cdns3_get_id(cdns))
103			return 1;
104
105	return 0;
106}
107
108/**
109 * cdns3_otg_disable_irq - Disable all OTG interrupts
110 * @cdns: Pointer to controller context structure
111 */
112static void cdns3_otg_disable_irq(struct cdns3 *cdns)
113{
114	writel(0, &cdns->otg_regs->ien);
115}
116
117/**
118 * cdns3_otg_enable_irq - enable id and sess_valid interrupts
119 * @cdns: Pointer to controller context structure
120 */
121static void cdns3_otg_enable_irq(struct cdns3 *cdns)
122{
123	writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT |
124	       OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_regs->ien);
125}
126
127/**
128 * cdns3_drd_switch_host - start/stop host
129 * @cdns: Pointer to controller context structure
130 * @on: 1 for start, 0 for stop
131 *
132 * Returns 0 on success otherwise negative errno
133 */
134int cdns3_drd_switch_host(struct cdns3 *cdns, int on)
135{
136	int ret, val;
137	u32 reg = OTGCMD_OTG_DIS;
 
 
 
 
 
 
 
 
 
 
 
138
139	/* switch OTG core */
140	if (on) {
141		writel(OTGCMD_HOST_BUS_REQ | reg, &cdns->otg_regs->cmd);
142
143		dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
144		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
145						val & OTGSTS_XHCI_READY,
146						1, 100000);
147		if (ret) {
148			dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
149			return ret;
150		}
151	} else {
152		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
153		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
154		       &cdns->otg_regs->cmd);
155		/* Waiting till H_IDLE state.*/
156		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
157					  !(val & OTGSTATE_HOST_STATE_MASK),
158					  1, 2000000);
159	}
160
161	return 0;
 
 
 
 
 
 
 
162}
163
164/**
165 * cdns3_drd_switch_gadget - start/stop gadget
166 * @cdns: Pointer to controller context structure
167 * @on: 1 for start, 0 for stop
168 *
169 * Returns 0 on success otherwise negative errno
170 */
171int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on)
172{
173	int ret, val;
174	u32 reg = OTGCMD_OTG_DIS;
175
176	/* switch OTG core */
177	if (on) {
178		writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
179
180		dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
181
182		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
183						val & OTGSTS_DEV_READY,
184						1, 100000);
185		if (ret) {
186			dev_err(cdns->dev, "timeout waiting for dev_ready\n");
187			return ret;
188		}
189	} else {
190		/*
191		 * driver should wait at least 10us after disabling Device
192		 * before turning-off Device (DEV_BUS_DROP)
193		 */
194		usleep_range(20, 30);
195		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
196		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
197		       &cdns->otg_regs->cmd);
198		/* Waiting till DEV_IDLE state.*/
199		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
200					  !(val & OTGSTATE_DEV_STATE_MASK),
201					  1, 2000000);
202	}
203
204	return 0;
205}
206
207/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
208 * cdns3_init_otg_mode - initialize drd controller
209 * @cdns: Pointer to controller context structure
210 *
211 * Returns 0 on success otherwise negative errno
212 */
213static int cdns3_init_otg_mode(struct cdns3 *cdns)
214{
215	int ret = 0;
216
217	cdns3_otg_disable_irq(cdns);
218	/* clear all interrupts */
219	writel(~0, &cdns->otg_regs->ivect);
220
221	ret = cdns3_set_mode(cdns, USB_DR_MODE_OTG);
222	if (ret)
223		return ret;
224
225	cdns3_otg_enable_irq(cdns);
226	return ret;
 
227}
228
229/**
230 * cdns3_drd_update_mode - initialize mode of operation
231 * @cdns: Pointer to controller context structure
232 *
233 * Returns 0 on success otherwise negative errno
234 */
235int cdns3_drd_update_mode(struct cdns3 *cdns)
236{
237	int ret = 0;
238
239	switch (cdns->dr_mode) {
240	case USB_DR_MODE_PERIPHERAL:
241		ret = cdns3_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
242		break;
243	case USB_DR_MODE_HOST:
244		ret = cdns3_set_mode(cdns, USB_DR_MODE_HOST);
245		break;
246	case USB_DR_MODE_OTG:
247		ret = cdns3_init_otg_mode(cdns);
248		break;
249	default:
250		dev_err(cdns->dev, "Unsupported mode of operation %d\n",
251			cdns->dr_mode);
252		return -EINVAL;
253	}
254
255	return ret;
256}
257
258static irqreturn_t cdns3_drd_thread_irq(int irq, void *data)
259{
260	struct cdns3 *cdns = data;
261
262	cdns3_hw_role_switch(cdns);
263
264	return IRQ_HANDLED;
265}
266
267/**
268 * cdns3_drd_irq - interrupt handler for OTG events
269 *
270 * @irq: irq number for cdns3 core device
271 * @data: structure of cdns3
272 *
273 * Returns IRQ_HANDLED or IRQ_NONE
274 */
275static irqreturn_t cdns3_drd_irq(int irq, void *data)
276{
277	irqreturn_t ret = IRQ_NONE;
278	struct cdns3 *cdns = data;
279	u32 reg;
280
281	if (cdns->dr_mode != USB_DR_MODE_OTG)
282		return ret;
283
284	reg = readl(&cdns->otg_regs->ivect);
285
286	if (!reg)
287		return ret;
288
289	if (reg & OTGIEN_ID_CHANGE_INT) {
290		dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n",
291			cdns3_get_id(cdns));
292
293		ret = IRQ_WAKE_THREAD;
294	}
295
296	if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) {
297		dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n",
298			cdns3_get_vbus(cdns));
299
300		ret = IRQ_WAKE_THREAD;
301	}
302
303	writel(~0, &cdns->otg_regs->ivect);
304	return ret;
305}
306
307int cdns3_drd_init(struct cdns3 *cdns)
308{
309	void __iomem *regs;
310	int ret = 0;
311	u32 state;
 
312
313	regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res);
314	if (IS_ERR(regs))
315		return PTR_ERR(regs);
316
317	/* Detection of DRD version. Controller has been released
318	 * in two versions. Both are similar, but they have same changes
319	 * in register maps.
320	 * The first register in old version is command register and it's read
321	 * only, so driver should read 0 from it. On the other hand, in v1
322	 * the first register contains device ID number which is not set to 0.
323	 * Driver uses this fact to detect the proper version of
324	 * controller.
325	 */
326	cdns->otg_v0_regs = regs;
327	if (!readl(&cdns->otg_v0_regs->cmd)) {
328		cdns->version  = CDNS3_CONTROLLER_V0;
329		cdns->otg_v1_regs = NULL;
330		cdns->otg_regs = regs;
331		writel(1, &cdns->otg_v0_regs->simulate);
332		dev_info(cdns->dev, "DRD version v0 (%08x)\n",
333			 readl(&cdns->otg_v0_regs->version));
334	} else {
335		cdns->otg_v0_regs = NULL;
336		cdns->otg_v1_regs = regs;
337		cdns->otg_regs = (void *)&cdns->otg_v1_regs->cmd;
338		cdns->version  = CDNS3_CONTROLLER_V1;
339		writel(1, &cdns->otg_v1_regs->simulate);
340		dev_info(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
341			 readl(&cdns->otg_v1_regs->did),
342			 readl(&cdns->otg_v1_regs->rid));
343	}
344
345	state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
346
347	/* Update dr_mode according to STRAP configuration. */
348	cdns->dr_mode = USB_DR_MODE_OTG;
349	if (state == OTGSTS_STRAP_HOST) {
350		dev_dbg(cdns->dev, "Controller strapped to HOST\n");
351		cdns->dr_mode = USB_DR_MODE_HOST;
352	} else if (state == OTGSTS_STRAP_GADGET) {
353		dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
354		cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
355	}
356
357	ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq,
358					cdns3_drd_irq,
359					cdns3_drd_thread_irq,
360					IRQF_SHARED,
361					dev_name(cdns->dev), cdns);
362
363	if (ret) {
364		dev_err(cdns->dev, "couldn't get otg_irq\n");
365		return ret;
366	}
367
368	state = readl(&cdns->otg_regs->sts);
369	if (OTGSTS_OTG_NRDY(state) != 0) {
370		dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
371		return -ENODEV;
372	}
373
374	return ret;
375}
376
377int cdns3_drd_exit(struct cdns3 *cdns)
378{
379	cdns3_otg_disable_irq(cdns);
380	return 0;
381}