xref: /openbmc/linux/arch/arm/common/scoop.c (revision aaf9128a)
1 /*
2  * Support code for the SCOOP interface found on various Sharp PDAs
3  *
4  * Copyright (c) 2004 Richard Purdie
5  *
6  *	Based on code written by Sharp/Lineo for 2.4 kernels
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  */
13 
14 #include <linux/device.h>
15 #include <linux/gpio.h>
16 #include <linux/string.h>
17 #include <linux/slab.h>
18 #include <linux/platform_device.h>
19 #include <linux/export.h>
20 #include <linux/io.h>
21 #include <asm/hardware/scoop.h>
22 
23 /* PCMCIA to Scoop linkage
24 
25    There is no easy way to link multiple scoop devices into one
26    single entity for the pxa2xx_pcmcia device so this structure
27    is used which is setup by the platform code.
28 
29    This file is never modular so this symbol is always
30    accessile to the board support files.
31 */
32 struct scoop_pcmcia_config *platform_scoop_config;
33 EXPORT_SYMBOL(platform_scoop_config);
34 
35 struct  scoop_dev {
36 	void __iomem *base;
37 	struct gpio_chip gpio;
38 	spinlock_t scoop_lock;
39 	unsigned short suspend_clr;
40 	unsigned short suspend_set;
41 	u32 scoop_gpwr;
42 };
43 
44 void reset_scoop(struct device *dev)
45 {
46 	struct scoop_dev *sdev = dev_get_drvdata(dev);
47 
48 	iowrite16(0x0100, sdev->base + SCOOP_MCR);  /* 00 */
49 	iowrite16(0x0000, sdev->base + SCOOP_CDR);  /* 04 */
50 	iowrite16(0x0000, sdev->base + SCOOP_CCR);  /* 10 */
51 	iowrite16(0x0000, sdev->base + SCOOP_IMR);  /* 18 */
52 	iowrite16(0x00FF, sdev->base + SCOOP_IRM);  /* 14 */
53 	iowrite16(0x0000, sdev->base + SCOOP_ISR);  /* 1C */
54 	iowrite16(0x0000, sdev->base + SCOOP_IRM);
55 }
56 
57 static void __scoop_gpio_set(struct scoop_dev *sdev,
58 			unsigned offset, int value)
59 {
60 	unsigned short gpwr;
61 
62 	gpwr = ioread16(sdev->base + SCOOP_GPWR);
63 	if (value)
64 		gpwr |= 1 << (offset + 1);
65 	else
66 		gpwr &= ~(1 << (offset + 1));
67 	iowrite16(gpwr, sdev->base + SCOOP_GPWR);
68 }
69 
70 static void scoop_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
71 {
72 	struct scoop_dev *sdev = gpiochip_get_data(chip);
73 	unsigned long flags;
74 
75 	spin_lock_irqsave(&sdev->scoop_lock, flags);
76 
77 	__scoop_gpio_set(sdev, offset, value);
78 
79 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
80 }
81 
82 static int scoop_gpio_get(struct gpio_chip *chip, unsigned offset)
83 {
84 	struct scoop_dev *sdev = gpiochip_get_data(chip);
85 
86 	/* XXX: I'm unsure, but it seems so */
87 	return !!(ioread16(sdev->base + SCOOP_GPRR) & (1 << (offset + 1)));
88 }
89 
90 static int scoop_gpio_direction_input(struct gpio_chip *chip,
91 			unsigned offset)
92 {
93 	struct scoop_dev *sdev = gpiochip_get_data(chip);
94 	unsigned long flags;
95 	unsigned short gpcr;
96 
97 	spin_lock_irqsave(&sdev->scoop_lock, flags);
98 
99 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
100 	gpcr &= ~(1 << (offset + 1));
101 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
102 
103 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
104 
105 	return 0;
106 }
107 
108 static int scoop_gpio_direction_output(struct gpio_chip *chip,
109 			unsigned offset, int value)
110 {
111 	struct scoop_dev *sdev = gpiochip_get_data(chip);
112 	unsigned long flags;
113 	unsigned short gpcr;
114 
115 	spin_lock_irqsave(&sdev->scoop_lock, flags);
116 
117 	__scoop_gpio_set(sdev, offset, value);
118 
119 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
120 	gpcr |= 1 << (offset + 1);
121 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
122 
123 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
124 
125 	return 0;
126 }
127 
128 unsigned short read_scoop_reg(struct device *dev, unsigned short reg)
129 {
130 	struct scoop_dev *sdev = dev_get_drvdata(dev);
131 	return ioread16(sdev->base + reg);
132 }
133 
134 void write_scoop_reg(struct device *dev, unsigned short reg, unsigned short data)
135 {
136 	struct scoop_dev *sdev = dev_get_drvdata(dev);
137 	iowrite16(data, sdev->base + reg);
138 }
139 
140 EXPORT_SYMBOL(reset_scoop);
141 EXPORT_SYMBOL(read_scoop_reg);
142 EXPORT_SYMBOL(write_scoop_reg);
143 
144 #ifdef CONFIG_PM
145 static void check_scoop_reg(struct scoop_dev *sdev)
146 {
147 	unsigned short mcr;
148 
149 	mcr = ioread16(sdev->base + SCOOP_MCR);
150 	if ((mcr & 0x100) == 0)
151 		iowrite16(0x0101, sdev->base + SCOOP_MCR);
152 }
153 
154 static int scoop_suspend(struct platform_device *dev, pm_message_t state)
155 {
156 	struct scoop_dev *sdev = platform_get_drvdata(dev);
157 
158 	check_scoop_reg(sdev);
159 	sdev->scoop_gpwr = ioread16(sdev->base + SCOOP_GPWR);
160 	iowrite16((sdev->scoop_gpwr & ~sdev->suspend_clr) | sdev->suspend_set, sdev->base + SCOOP_GPWR);
161 
162 	return 0;
163 }
164 
165 static int scoop_resume(struct platform_device *dev)
166 {
167 	struct scoop_dev *sdev = platform_get_drvdata(dev);
168 
169 	check_scoop_reg(sdev);
170 	iowrite16(sdev->scoop_gpwr, sdev->base + SCOOP_GPWR);
171 
172 	return 0;
173 }
174 #else
175 #define scoop_suspend	NULL
176 #define scoop_resume	NULL
177 #endif
178 
179 static int scoop_probe(struct platform_device *pdev)
180 {
181 	struct scoop_dev *devptr;
182 	struct scoop_config *inf;
183 	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
184 	int ret;
185 
186 	if (!mem)
187 		return -EINVAL;
188 
189 	devptr = kzalloc(sizeof(struct scoop_dev), GFP_KERNEL);
190 	if (!devptr)
191 		return -ENOMEM;
192 
193 	spin_lock_init(&devptr->scoop_lock);
194 
195 	inf = pdev->dev.platform_data;
196 	devptr->base = ioremap(mem->start, resource_size(mem));
197 
198 	if (!devptr->base) {
199 		ret = -ENOMEM;
200 		goto err_ioremap;
201 	}
202 
203 	platform_set_drvdata(pdev, devptr);
204 
205 	printk("Sharp Scoop Device found at 0x%08x -> 0x%8p\n",(unsigned int)mem->start, devptr->base);
206 
207 	iowrite16(0x0140, devptr->base + SCOOP_MCR);
208 	reset_scoop(&pdev->dev);
209 	iowrite16(0x0000, devptr->base + SCOOP_CPR);
210 	iowrite16(inf->io_dir & 0xffff, devptr->base + SCOOP_GPCR);
211 	iowrite16(inf->io_out & 0xffff, devptr->base + SCOOP_GPWR);
212 
213 	devptr->suspend_clr = inf->suspend_clr;
214 	devptr->suspend_set = inf->suspend_set;
215 
216 	devptr->gpio.base = -1;
217 
218 	if (inf->gpio_base != 0) {
219 		devptr->gpio.label = dev_name(&pdev->dev);
220 		devptr->gpio.base = inf->gpio_base;
221 		devptr->gpio.ngpio = 12; /* PA11 = 0, PA12 = 1, etc. up to PA22 = 11 */
222 		devptr->gpio.set = scoop_gpio_set;
223 		devptr->gpio.get = scoop_gpio_get;
224 		devptr->gpio.direction_input = scoop_gpio_direction_input;
225 		devptr->gpio.direction_output = scoop_gpio_direction_output;
226 
227 		ret = gpiochip_add_data(&devptr->gpio, devptr);
228 		if (ret)
229 			goto err_gpio;
230 	}
231 
232 	return 0;
233 
234 err_gpio:
235 	platform_set_drvdata(pdev, NULL);
236 err_ioremap:
237 	iounmap(devptr->base);
238 	kfree(devptr);
239 
240 	return ret;
241 }
242 
243 static int scoop_remove(struct platform_device *pdev)
244 {
245 	struct scoop_dev *sdev = platform_get_drvdata(pdev);
246 
247 	if (!sdev)
248 		return -EINVAL;
249 
250 	if (sdev->gpio.base != -1)
251 		gpiochip_remove(&sdev->gpio);
252 
253 	platform_set_drvdata(pdev, NULL);
254 	iounmap(sdev->base);
255 	kfree(sdev);
256 
257 	return 0;
258 }
259 
260 static struct platform_driver scoop_driver = {
261 	.probe		= scoop_probe,
262 	.remove		= scoop_remove,
263 	.suspend	= scoop_suspend,
264 	.resume		= scoop_resume,
265 	.driver		= {
266 		.name	= "sharp-scoop",
267 	},
268 };
269 
270 static int __init scoop_init(void)
271 {
272 	return platform_driver_register(&scoop_driver);
273 }
274 
275 subsys_initcall(scoop_init);
276