1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Support code for the SCOOP interface found on various Sharp PDAs
4  *
5  * Copyright (c) 2004 Richard Purdie
6  *
7  *	Based on code written by Sharp/Lineo for 2.4 kernels
8  */
9 
10 #include <linux/device.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/string.h>
13 #include <linux/slab.h>
14 #include <linux/platform_device.h>
15 #include <linux/export.h>
16 #include <linux/io.h>
17 #include <asm/hardware/scoop.h>
18 
19 /* PCMCIA to Scoop linkage
20 
21    There is no easy way to link multiple scoop devices into one
22    single entity for the pxa2xx_pcmcia device so this structure
23    is used which is setup by the platform code.
24 
25    This file is never modular so this symbol is always
26    accessile to the board support files.
27 */
28 struct scoop_pcmcia_config *platform_scoop_config;
29 EXPORT_SYMBOL(platform_scoop_config);
30 
31 struct  scoop_dev {
32 	void __iomem *base;
33 	struct gpio_chip gpio;
34 	spinlock_t scoop_lock;
35 	unsigned short suspend_clr;
36 	unsigned short suspend_set;
37 	u32 scoop_gpwr;
38 };
39 
40 void reset_scoop(struct device *dev)
41 {
42 	struct scoop_dev *sdev = dev_get_drvdata(dev);
43 
44 	iowrite16(0x0100, sdev->base + SCOOP_MCR);  /* 00 */
45 	iowrite16(0x0000, sdev->base + SCOOP_CDR);  /* 04 */
46 	iowrite16(0x0000, sdev->base + SCOOP_CCR);  /* 10 */
47 	iowrite16(0x0000, sdev->base + SCOOP_IMR);  /* 18 */
48 	iowrite16(0x00FF, sdev->base + SCOOP_IRM);  /* 14 */
49 	iowrite16(0x0000, sdev->base + SCOOP_ISR);  /* 1C */
50 	iowrite16(0x0000, sdev->base + SCOOP_IRM);
51 }
52 
53 static void __scoop_gpio_set(struct scoop_dev *sdev,
54 			unsigned offset, int value)
55 {
56 	unsigned short gpwr;
57 
58 	gpwr = ioread16(sdev->base + SCOOP_GPWR);
59 	if (value)
60 		gpwr |= 1 << (offset + 1);
61 	else
62 		gpwr &= ~(1 << (offset + 1));
63 	iowrite16(gpwr, sdev->base + SCOOP_GPWR);
64 }
65 
66 static int scoop_gpio_set(struct gpio_chip *chip, unsigned int offset,
67 			  int value)
68 {
69 	struct scoop_dev *sdev = gpiochip_get_data(chip);
70 	unsigned long flags;
71 
72 	spin_lock_irqsave(&sdev->scoop_lock, flags);
73 
74 	__scoop_gpio_set(sdev, offset, value);
75 
76 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
77 
78 	return 0;
79 }
80 
81 static int scoop_gpio_get(struct gpio_chip *chip, unsigned offset)
82 {
83 	struct scoop_dev *sdev = gpiochip_get_data(chip);
84 
85 	/* XXX: I'm unsure, but it seems so */
86 	return !!(ioread16(sdev->base + SCOOP_GPRR) & (1 << (offset + 1)));
87 }
88 
89 static int scoop_gpio_direction_input(struct gpio_chip *chip,
90 			unsigned offset)
91 {
92 	struct scoop_dev *sdev = gpiochip_get_data(chip);
93 	unsigned long flags;
94 	unsigned short gpcr;
95 
96 	spin_lock_irqsave(&sdev->scoop_lock, flags);
97 
98 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
99 	gpcr &= ~(1 << (offset + 1));
100 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
101 
102 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
103 
104 	return 0;
105 }
106 
107 static int scoop_gpio_direction_output(struct gpio_chip *chip,
108 			unsigned offset, int value)
109 {
110 	struct scoop_dev *sdev = gpiochip_get_data(chip);
111 	unsigned long flags;
112 	unsigned short gpcr;
113 
114 	spin_lock_irqsave(&sdev->scoop_lock, flags);
115 
116 	__scoop_gpio_set(sdev, offset, value);
117 
118 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
119 	gpcr |= 1 << (offset + 1);
120 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
121 
122 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
123 
124 	return 0;
125 }
126 
127 unsigned short read_scoop_reg(struct device *dev, unsigned short reg)
128 {
129 	struct scoop_dev *sdev = dev_get_drvdata(dev);
130 	return ioread16(sdev->base + reg);
131 }
132 
133 void write_scoop_reg(struct device *dev, unsigned short reg, unsigned short data)
134 {
135 	struct scoop_dev *sdev = dev_get_drvdata(dev);
136 	iowrite16(data, sdev->base + reg);
137 }
138 
139 EXPORT_SYMBOL(reset_scoop);
140 EXPORT_SYMBOL(read_scoop_reg);
141 EXPORT_SYMBOL(write_scoop_reg);
142 
143 #ifdef CONFIG_PM
144 static void check_scoop_reg(struct scoop_dev *sdev)
145 {
146 	unsigned short mcr;
147 
148 	mcr = ioread16(sdev->base + SCOOP_MCR);
149 	if ((mcr & 0x100) == 0)
150 		iowrite16(0x0101, sdev->base + SCOOP_MCR);
151 }
152 
153 static int scoop_suspend(struct platform_device *dev, pm_message_t state)
154 {
155 	struct scoop_dev *sdev = platform_get_drvdata(dev);
156 
157 	check_scoop_reg(sdev);
158 	sdev->scoop_gpwr = ioread16(sdev->base + SCOOP_GPWR);
159 	iowrite16((sdev->scoop_gpwr & ~sdev->suspend_clr) | sdev->suspend_set, sdev->base + SCOOP_GPWR);
160 
161 	return 0;
162 }
163 
164 static int scoop_resume(struct platform_device *dev)
165 {
166 	struct scoop_dev *sdev = platform_get_drvdata(dev);
167 
168 	check_scoop_reg(sdev);
169 	iowrite16(sdev->scoop_gpwr, sdev->base + SCOOP_GPWR);
170 
171 	return 0;
172 }
173 #else
174 #define scoop_suspend	NULL
175 #define scoop_resume	NULL
176 #endif
177 
178 static int scoop_probe(struct platform_device *pdev)
179 {
180 	struct scoop_dev *devptr;
181 	struct scoop_config *inf;
182 	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
183 	int ret;
184 
185 	if (!mem)
186 		return -EINVAL;
187 
188 	devptr = kzalloc(sizeof(struct scoop_dev), GFP_KERNEL);
189 	if (!devptr)
190 		return -ENOMEM;
191 
192 	spin_lock_init(&devptr->scoop_lock);
193 
194 	inf = pdev->dev.platform_data;
195 	devptr->base = ioremap(mem->start, resource_size(mem));
196 
197 	if (!devptr->base) {
198 		ret = -ENOMEM;
199 		goto err_ioremap;
200 	}
201 
202 	platform_set_drvdata(pdev, devptr);
203 
204 	printk("Sharp Scoop Device found at 0x%08x -> 0x%8p\n",(unsigned int)mem->start, devptr->base);
205 
206 	iowrite16(0x0140, devptr->base + SCOOP_MCR);
207 	reset_scoop(&pdev->dev);
208 	iowrite16(0x0000, devptr->base + SCOOP_CPR);
209 	iowrite16(inf->io_dir & 0xffff, devptr->base + SCOOP_GPCR);
210 	iowrite16(inf->io_out & 0xffff, devptr->base + SCOOP_GPWR);
211 
212 	devptr->suspend_clr = inf->suspend_clr;
213 	devptr->suspend_set = inf->suspend_set;
214 
215 	devptr->gpio.base = -1;
216 
217 	if (inf->gpio_base != 0) {
218 		devptr->gpio.label = dev_name(&pdev->dev);
219 		devptr->gpio.base = inf->gpio_base;
220 		devptr->gpio.ngpio = 12; /* PA11 = 0, PA12 = 1, etc. up to PA22 = 11 */
221 		devptr->gpio.set_rv = scoop_gpio_set;
222 		devptr->gpio.get = scoop_gpio_get;
223 		devptr->gpio.direction_input = scoop_gpio_direction_input;
224 		devptr->gpio.direction_output = scoop_gpio_direction_output;
225 
226 		ret = gpiochip_add_data(&devptr->gpio, devptr);
227 		if (ret)
228 			goto err_gpio;
229 	}
230 
231 	return 0;
232 
233 err_gpio:
234 	platform_set_drvdata(pdev, NULL);
235 err_ioremap:
236 	iounmap(devptr->base);
237 	kfree(devptr);
238 
239 	return ret;
240 }
241 
242 static void scoop_remove(struct platform_device *pdev)
243 {
244 	struct scoop_dev *sdev = platform_get_drvdata(pdev);
245 
246 	if (sdev->gpio.base != -1)
247 		gpiochip_remove(&sdev->gpio);
248 
249 	platform_set_drvdata(pdev, NULL);
250 	iounmap(sdev->base);
251 	kfree(sdev);
252 }
253 
254 static struct platform_driver scoop_driver = {
255 	.probe		= scoop_probe,
256 	.remove		= scoop_remove,
257 	.suspend	= scoop_suspend,
258 	.resume		= scoop_resume,
259 	.driver		= {
260 		.name	= "sharp-scoop",
261 	},
262 };
263 
264 static int __init scoop_init(void)
265 {
266 	return platform_driver_register(&scoop_driver);
267 }
268 
269 subsys_initcall(scoop_init);
270