1/*
  2 * mtu3_dr.c - dual role switch and host glue layer
  3 *
  4 * Copyright (C) 2016 MediaTek Inc.
  5 *
  6 * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
  7 *
  8 * This software is licensed under the terms of the GNU General Public
  9 * License version 2, as published by the Free Software Foundation, and
 10 * may be copied, distributed, and modified under those terms.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 */
 18
 19#include <linux/clk.h>
 20#include <linux/iopoll.h>
 21#include <linux/irq.h>
 22#include <linux/kernel.h>
 23#include <linux/mfd/syscon.h>
 24#include <linux/of_device.h>
 25#include <linux/regmap.h>
 26
 27#include "mtu3.h"
 28#include "mtu3_dr.h"
 29
 30#define PERI_WK_CTRL1		0x404
 31#define UWK_CTL1_IS_C(x)	(((x) & 0xf) << 26)
 32#define UWK_CTL1_IS_E		BIT(25)
 33#define UWK_CTL1_IDDIG_C(x)	(((x) & 0xf) << 11)  /* cycle debounce */
 34#define UWK_CTL1_IDDIG_E	BIT(10) /* enable debounce */
 35#define UWK_CTL1_IDDIG_P	BIT(9)  /* polarity */
 36#define UWK_CTL1_IS_P		BIT(6)  /* polarity for ip sleep */
 37
 38/*
 39 * ip-sleep wakeup mode:
 40 * all clocks can be turn off, but power domain should be kept on
 41 */
 42static void ssusb_wakeup_ip_sleep_en(struct ssusb_mtk *ssusb)
 43{
 44	u32 tmp;
 45	struct regmap *pericfg = ssusb->pericfg;
 46
 47	regmap_read(pericfg, PERI_WK_CTRL1, &tmp);
 48	tmp &= ~UWK_CTL1_IS_P;
 49	tmp &= ~(UWK_CTL1_IS_C(0xf));
 50	tmp |= UWK_CTL1_IS_C(0x8);
 51	regmap_write(pericfg, PERI_WK_CTRL1, tmp);
 52	regmap_write(pericfg, PERI_WK_CTRL1, tmp | UWK_CTL1_IS_E);
 53
 54	regmap_read(pericfg, PERI_WK_CTRL1, &tmp);
 55	dev_dbg(ssusb->dev, "%s(): WK_CTRL1[P6,E25,C26:29]=%#x\n",
 56		__func__, tmp);
 57}
 58
 59static void ssusb_wakeup_ip_sleep_dis(struct ssusb_mtk *ssusb)
 60{
 61	u32 tmp;
 62
 63	regmap_read(ssusb->pericfg, PERI_WK_CTRL1, &tmp);
 64	tmp &= ~UWK_CTL1_IS_E;
 65	regmap_write(ssusb->pericfg, PERI_WK_CTRL1, tmp);
 66}
 67
 68int ssusb_wakeup_of_property_parse(struct ssusb_mtk *ssusb,
 69				struct device_node *dn)
 70{
 71	struct device *dev = ssusb->dev;
 72
 73	/*
 74	 * Wakeup function is optional, so it is not an error if this property
 75	 * does not exist, and in such case, no need to get relative
 76	 * properties anymore.
 77	 */
 78	ssusb->wakeup_en = of_property_read_bool(dn, "mediatek,enable-wakeup");
 79	if (!ssusb->wakeup_en)
 80		return 0;
 81
 82	ssusb->wk_deb_p0 = devm_clk_get(dev, "wakeup_deb_p0");
 83	if (IS_ERR(ssusb->wk_deb_p0)) {
 84		dev_err(dev, "fail to get wakeup_deb_p0\n");
 85		return PTR_ERR(ssusb->wk_deb_p0);
 86	}
 87
 88	if (of_property_read_bool(dn, "wakeup_deb_p1")) {
 89		ssusb->wk_deb_p1 = devm_clk_get(dev, "wakeup_deb_p1");
 90		if (IS_ERR(ssusb->wk_deb_p1)) {
 91			dev_err(dev, "fail to get wakeup_deb_p1\n");
 92			return PTR_ERR(ssusb->wk_deb_p1);
 93		}
 94	}
 95
 96	ssusb->pericfg = syscon_regmap_lookup_by_phandle(dn,
 97						"mediatek,syscon-wakeup");
 98	if (IS_ERR(ssusb->pericfg)) {
 99		dev_err(dev, "fail to get pericfg regs\n");
100		return PTR_ERR(ssusb->pericfg);
101	}
102
103	return 0;
104}
105
106static int ssusb_wakeup_clks_enable(struct ssusb_mtk *ssusb)
107{
108	int ret;
109
110	ret = clk_prepare_enable(ssusb->wk_deb_p0);
111	if (ret) {
112		dev_err(ssusb->dev, "failed to enable wk_deb_p0\n");
113		goto usb_p0_err;
114	}
115
116	ret = clk_prepare_enable(ssusb->wk_deb_p1);
117	if (ret) {
118		dev_err(ssusb->dev, "failed to enable wk_deb_p1\n");
119		goto usb_p1_err;
120	}
121
122	return 0;
123
124usb_p1_err:
125	clk_disable_unprepare(ssusb->wk_deb_p0);
126usb_p0_err:
127	return -EINVAL;
128}
129
130static void ssusb_wakeup_clks_disable(struct ssusb_mtk *ssusb)
131{
132	clk_disable_unprepare(ssusb->wk_deb_p1);
133	clk_disable_unprepare(ssusb->wk_deb_p0);
134}
135
136static void host_ports_num_get(struct ssusb_mtk *ssusb)
137{
138	u32 xhci_cap;
139
140	xhci_cap = mtu3_readl(ssusb->ippc_base, U3D_SSUSB_IP_XHCI_CAP);
141	ssusb->u2_ports = SSUSB_IP_XHCI_U2_PORT_NUM(xhci_cap);
142	ssusb->u3_ports = SSUSB_IP_XHCI_U3_PORT_NUM(xhci_cap);
143
144	dev_dbg(ssusb->dev, "host - u2_ports:%d, u3_ports:%d\n",
145		 ssusb->u2_ports, ssusb->u3_ports);
146}
147
148/* only configure ports will be used later */
149int ssusb_host_enable(struct ssusb_mtk *ssusb)
150{
151	void __iomem *ibase = ssusb->ippc_base;
152	int num_u3p = ssusb->u3_ports;
153	int num_u2p = ssusb->u2_ports;
154	u32 check_clk;
155	u32 value;
156	int i;
157
158	/* power on host ip */
159	mtu3_clrbits(ibase, U3D_SSUSB_IP_PW_CTRL1, SSUSB_IP_HOST_PDN);
160
161	/* power on and enable all u3 ports */
162	for (i = 0; i < num_u3p; i++) {
163		value = mtu3_readl(ibase, SSUSB_U3_CTRL(i));
164		value &= ~(SSUSB_U3_PORT_PDN | SSUSB_U3_PORT_DIS);
165		value |= SSUSB_U3_PORT_HOST_SEL;
166		mtu3_writel(ibase, SSUSB_U3_CTRL(i), value);
167	}
168
169	/* power on and enable all u2 ports */
170	for (i = 0; i < num_u2p; i++) {
171		value = mtu3_readl(ibase, SSUSB_U2_CTRL(i));
172		value &= ~(SSUSB_U2_PORT_PDN | SSUSB_U2_PORT_DIS);
173		value |= SSUSB_U2_PORT_HOST_SEL;
174		mtu3_writel(ibase, SSUSB_U2_CTRL(i), value);
175	}
176
177	check_clk = SSUSB_XHCI_RST_B_STS;
178	if (num_u3p)
179		check_clk = SSUSB_U3_MAC_RST_B_STS;
180
181	return ssusb_check_clocks(ssusb, check_clk);
182}
183
184int ssusb_host_disable(struct ssusb_mtk *ssusb, bool suspend)
185{
186	void __iomem *ibase = ssusb->ippc_base;
187	int num_u3p = ssusb->u3_ports;
188	int num_u2p = ssusb->u2_ports;
189	u32 value;
190	int ret;
191	int i;
192
193	/* power down and disable all u3 ports */
194	for (i = 0; i < num_u3p; i++) {
195		value = mtu3_readl(ibase, SSUSB_U3_CTRL(i));
196		value |= SSUSB_U3_PORT_PDN;
197		value |= suspend ? 0 : SSUSB_U3_PORT_DIS;
198		mtu3_writel(ibase, SSUSB_U3_CTRL(i), value);
199	}
200
201	/* power down and disable all u2 ports */
202	for (i = 0; i < num_u2p; i++) {
203		value = mtu3_readl(ibase, SSUSB_U2_CTRL(i));
204		value |= SSUSB_U2_PORT_PDN;
205		value |= suspend ? 0 : SSUSB_U2_PORT_DIS;
206		mtu3_writel(ibase, SSUSB_U2_CTRL(i), value);
207	}
208
209	/* power down host ip */
210	mtu3_setbits(ibase, U3D_SSUSB_IP_PW_CTRL1, SSUSB_IP_HOST_PDN);
211
212	if (!suspend)
213		return 0;
214
215	/* wait for host ip to sleep */
216	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS1, value,
217			  (value & SSUSB_IP_SLEEP_STS), 100, 100000);
218	if (ret)
219		dev_err(ssusb->dev, "ip sleep failed!!!\n");
220
221	return ret;
222}
223
224static void ssusb_host_setup(struct ssusb_mtk *ssusb)
225{
226	host_ports_num_get(ssusb);
227
228	/*
229	 * power on host and power on/enable all ports
230	 * if support OTG, gadget driver will switch port0 to device mode
231	 */
232	ssusb_host_enable(ssusb);
233
234	/* if port0 supports dual-role, works as host mode by default */
235	ssusb_set_vbus(&ssusb->otg_switch, 1);
236}
237
238static void ssusb_host_cleanup(struct ssusb_mtk *ssusb)
239{
240	if (ssusb->is_host)
241		ssusb_set_vbus(&ssusb->otg_switch, 0);
242
243	ssusb_host_disable(ssusb, false);
244}
245
246/*
247 * If host supports multiple ports, the VBUSes(5V) of ports except port0
248 * which supports OTG are better to be enabled by default in DTS.
249 * Because the host driver will keep link with devices attached when system
250 * enters suspend mode, so no need to control VBUSes after initialization.
251 */
252int ssusb_host_init(struct ssusb_mtk *ssusb, struct device_node *parent_dn)
253{
254	struct device *parent_dev = ssusb->dev;
255	int ret;
256
257	ssusb_host_setup(ssusb);
258
259	ret = of_platform_populate(parent_dn, NULL, NULL, parent_dev);
260	if (ret) {
261		dev_dbg(parent_dev, "failed to create child devices at %s\n",
262				parent_dn->full_name);
263		return ret;
264	}
265
266	dev_info(parent_dev, "xHCI platform device register success...\n");
267
268	return 0;
269}
270
271void ssusb_host_exit(struct ssusb_mtk *ssusb)
272{
273	of_platform_depopulate(ssusb->dev);
274	ssusb_host_cleanup(ssusb);
275}
276
277int ssusb_wakeup_enable(struct ssusb_mtk *ssusb)
278{
279	int ret = 0;
280
281	if (ssusb->wakeup_en) {
282		ret = ssusb_wakeup_clks_enable(ssusb);
283		ssusb_wakeup_ip_sleep_en(ssusb);
284	}
285	return ret;
286}
287
288void ssusb_wakeup_disable(struct ssusb_mtk *ssusb)
289{
290	if (ssusb->wakeup_en) {
291		ssusb_wakeup_ip_sleep_dis(ssusb);
292		ssusb_wakeup_clks_disable(ssusb);
293	}
294}