1 /*
2  * Driver for the NXP ISP1760 chip
3  *
4  * Copyright 2014 Laurent Pinchart
5  * Copyright 2007 Sebastian Siewior
6  *
7  * Contacts:
8  *	Sebastian Siewior <bigeasy@linutronix.de>
9  *	Laurent Pinchart <laurent.pinchart@ideasonboard.com>
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License
13  * version 2 as published by the Free Software Foundation.
14  */
15 
16 #include <linux/delay.h>
17 #include <linux/gpio/consumer.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 #include <linux/usb.h>
23 
24 #include "isp1760-core.h"
25 #include "isp1760-hcd.h"
26 #include "isp1760-regs.h"
27 #include "isp1760-udc.h"
28 
29 static void isp1760_init_core(struct isp1760_device *isp)
30 {
31 	u32 otgctrl;
32 	u32 hwmode;
33 
34 	/* Low-level chip reset */
35 	if (isp->rst_gpio) {
36 		gpiod_set_value_cansleep(isp->rst_gpio, 1);
37 		mdelay(50);
38 		gpiod_set_value_cansleep(isp->rst_gpio, 0);
39 	}
40 
41 	/*
42 	 * Reset the host controller, including the CPU interface
43 	 * configuration.
44 	 */
45 	isp1760_write32(isp->regs, HC_RESET_REG, SW_RESET_RESET_ALL);
46 	msleep(100);
47 
48 	/* Setup HW Mode Control: This assumes a level active-low interrupt */
49 	hwmode = HW_DATA_BUS_32BIT;
50 
51 	if (isp->devflags & ISP1760_FLAG_BUS_WIDTH_16)
52 		hwmode &= ~HW_DATA_BUS_32BIT;
53 	if (isp->devflags & ISP1760_FLAG_ANALOG_OC)
54 		hwmode |= HW_ANA_DIGI_OC;
55 	if (isp->devflags & ISP1760_FLAG_DACK_POL_HIGH)
56 		hwmode |= HW_DACK_POL_HIGH;
57 	if (isp->devflags & ISP1760_FLAG_DREQ_POL_HIGH)
58 		hwmode |= HW_DREQ_POL_HIGH;
59 	if (isp->devflags & ISP1760_FLAG_INTR_POL_HIGH)
60 		hwmode |= HW_INTR_HIGH_ACT;
61 	if (isp->devflags & ISP1760_FLAG_INTR_EDGE_TRIG)
62 		hwmode |= HW_INTR_EDGE_TRIG;
63 
64 	/*
65 	 * The ISP1761 has a dedicated DC IRQ line but supports sharing the HC
66 	 * IRQ line for both the host and device controllers. Hardcode IRQ
67 	 * sharing for now and disable the DC interrupts globally to avoid
68 	 * spurious interrupts during HCD registration.
69 	 */
70 	if (isp->devflags & ISP1760_FLAG_ISP1761) {
71 		isp1760_write32(isp->regs, DC_MODE, 0);
72 		hwmode |= HW_COMN_IRQ;
73 	}
74 
75 	/*
76 	 * We have to set this first in case we're in 16-bit mode.
77 	 * Write it twice to ensure correct upper bits if switching
78 	 * to 16-bit mode.
79 	 */
80 	isp1760_write32(isp->regs, HC_HW_MODE_CTRL, hwmode);
81 	isp1760_write32(isp->regs, HC_HW_MODE_CTRL, hwmode);
82 
83 	/*
84 	 * PORT 1 Control register of the ISP1760 is the OTG control register
85 	 * on ISP1761.
86 	 *
87 	 * TODO: Really support OTG. For now we configure port 1 in device mode
88 	 * when OTG is requested.
89 	 */
90 	if ((isp->devflags & ISP1760_FLAG_ISP1761) &&
91 	    (isp->devflags & ISP1760_FLAG_OTG_EN))
92 		otgctrl = ((HW_DM_PULLDOWN | HW_DP_PULLDOWN) << 16)
93 			| HW_OTG_DISABLE;
94 	else
95 		otgctrl = (HW_SW_SEL_HC_DC << 16)
96 			| (HW_VBUS_DRV | HW_SEL_CP_EXT);
97 
98 	isp1760_write32(isp->regs, HC_PORT1_CTRL, otgctrl);
99 
100 	dev_info(isp->dev, "bus width: %u, oc: %s\n",
101 		 isp->devflags & ISP1760_FLAG_BUS_WIDTH_16 ? 16 : 32,
102 		 isp->devflags & ISP1760_FLAG_ANALOG_OC ? "analog" : "digital");
103 }
104 
105 void isp1760_set_pullup(struct isp1760_device *isp, bool enable)
106 {
107 	isp1760_write32(isp->regs, HW_OTG_CTRL_SET,
108 			enable ? HW_DP_PULLUP : HW_DP_PULLUP << 16);
109 }
110 
111 int isp1760_register(struct resource *mem, int irq, unsigned long irqflags,
112 		     struct device *dev, unsigned int devflags)
113 {
114 	struct isp1760_device *isp;
115 	bool udc_disabled = !(devflags & ISP1760_FLAG_ISP1761);
116 	int ret;
117 
118 	/*
119 	 * If neither the HCD not the UDC is enabled return an error, as no
120 	 * device would be registered.
121 	 */
122 	if ((!IS_ENABLED(CONFIG_USB_ISP1760_HCD) || usb_disabled()) &&
123 	    (!IS_ENABLED(CONFIG_USB_ISP1761_UDC) || udc_disabled))
124 		return -ENODEV;
125 
126 	/* prevent usb-core allocating DMA pages */
127 	dev->dma_mask = NULL;
128 
129 	isp = devm_kzalloc(dev, sizeof(*isp), GFP_KERNEL);
130 	if (!isp)
131 		return -ENOMEM;
132 
133 	isp->dev = dev;
134 	isp->devflags = devflags;
135 
136 	isp->rst_gpio = devm_gpiod_get_optional(dev, NULL, GPIOD_OUT_HIGH);
137 	if (IS_ERR(isp->rst_gpio))
138 		return PTR_ERR(isp->rst_gpio);
139 
140 	isp->regs = devm_ioremap_resource(dev, mem);
141 	if (IS_ERR(isp->regs))
142 		return PTR_ERR(isp->regs);
143 
144 	isp1760_init_core(isp);
145 
146 	if (IS_ENABLED(CONFIG_USB_ISP1760_HCD) && !usb_disabled()) {
147 		ret = isp1760_hcd_register(&isp->hcd, isp->regs, mem, irq,
148 					   irqflags | IRQF_SHARED, dev);
149 		if (ret < 0)
150 			return ret;
151 	}
152 
153 	if (IS_ENABLED(CONFIG_USB_ISP1761_UDC) && !udc_disabled) {
154 		ret = isp1760_udc_register(isp, irq, irqflags);
155 		if (ret < 0) {
156 			isp1760_hcd_unregister(&isp->hcd);
157 			return ret;
158 		}
159 	}
160 
161 	dev_set_drvdata(dev, isp);
162 
163 	return 0;
164 }
165 
166 void isp1760_unregister(struct device *dev)
167 {
168 	struct isp1760_device *isp = dev_get_drvdata(dev);
169 
170 	isp1760_udc_unregister(isp);
171 	isp1760_hcd_unregister(&isp->hcd);
172 }
173 
174 MODULE_DESCRIPTION("Driver for the ISP1760 USB-controller from NXP");
175 MODULE_AUTHOR("Sebastian Siewior <bigeasy@linuxtronix.de>");
176 MODULE_LICENSE("GPL v2");
177