xref: /openbmc/linux/arch/arm/common/scoop.c (revision 6c33a6f4)
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 void scoop_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
67 {
68 	struct scoop_dev *sdev = gpiochip_get_data(chip);
69 	unsigned long flags;
70 
71 	spin_lock_irqsave(&sdev->scoop_lock, flags);
72 
73 	__scoop_gpio_set(sdev, offset, value);
74 
75 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
76 }
77 
78 static int scoop_gpio_get(struct gpio_chip *chip, unsigned offset)
79 {
80 	struct scoop_dev *sdev = gpiochip_get_data(chip);
81 
82 	/* XXX: I'm unsure, but it seems so */
83 	return !!(ioread16(sdev->base + SCOOP_GPRR) & (1 << (offset + 1)));
84 }
85 
86 static int scoop_gpio_direction_input(struct gpio_chip *chip,
87 			unsigned offset)
88 {
89 	struct scoop_dev *sdev = gpiochip_get_data(chip);
90 	unsigned long flags;
91 	unsigned short gpcr;
92 
93 	spin_lock_irqsave(&sdev->scoop_lock, flags);
94 
95 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
96 	gpcr &= ~(1 << (offset + 1));
97 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
98 
99 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
100 
101 	return 0;
102 }
103 
104 static int scoop_gpio_direction_output(struct gpio_chip *chip,
105 			unsigned offset, int value)
106 {
107 	struct scoop_dev *sdev = gpiochip_get_data(chip);
108 	unsigned long flags;
109 	unsigned short gpcr;
110 
111 	spin_lock_irqsave(&sdev->scoop_lock, flags);
112 
113 	__scoop_gpio_set(sdev, offset, value);
114 
115 	gpcr = ioread16(sdev->base + SCOOP_GPCR);
116 	gpcr |= 1 << (offset + 1);
117 	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
118 
119 	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
120 
121 	return 0;
122 }
123 
124 unsigned short read_scoop_reg(struct device *dev, unsigned short reg)
125 {
126 	struct scoop_dev *sdev = dev_get_drvdata(dev);
127 	return ioread16(sdev->base + reg);
128 }
129 
130 void write_scoop_reg(struct device *dev, unsigned short reg, unsigned short data)
131 {
132 	struct scoop_dev *sdev = dev_get_drvdata(dev);
133 	iowrite16(data, sdev->base + reg);
134 }
135 
136 EXPORT_SYMBOL(reset_scoop);
137 EXPORT_SYMBOL(read_scoop_reg);
138 EXPORT_SYMBOL(write_scoop_reg);
139 
140 #ifdef CONFIG_PM
141 static void check_scoop_reg(struct scoop_dev *sdev)
142 {
143 	unsigned short mcr;
144 
145 	mcr = ioread16(sdev->base + SCOOP_MCR);
146 	if ((mcr & 0x100) == 0)
147 		iowrite16(0x0101, sdev->base + SCOOP_MCR);
148 }
149 
150 static int scoop_suspend(struct platform_device *dev, pm_message_t state)
151 {
152 	struct scoop_dev *sdev = platform_get_drvdata(dev);
153 
154 	check_scoop_reg(sdev);
155 	sdev->scoop_gpwr = ioread16(sdev->base + SCOOP_GPWR);
156 	iowrite16((sdev->scoop_gpwr & ~sdev->suspend_clr) | sdev->suspend_set, sdev->base + SCOOP_GPWR);
157 
158 	return 0;
159 }
160 
161 static int scoop_resume(struct platform_device *dev)
162 {
163 	struct scoop_dev *sdev = platform_get_drvdata(dev);
164 
165 	check_scoop_reg(sdev);
166 	iowrite16(sdev->scoop_gpwr, sdev->base + SCOOP_GPWR);
167 
168 	return 0;
169 }
170 #else
171 #define scoop_suspend	NULL
172 #define scoop_resume	NULL
173 #endif
174 
175 static int scoop_probe(struct platform_device *pdev)
176 {
177 	struct scoop_dev *devptr;
178 	struct scoop_config *inf;
179 	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
180 	int ret;
181 
182 	if (!mem)
183 		return -EINVAL;
184 
185 	devptr = kzalloc(sizeof(struct scoop_dev), GFP_KERNEL);
186 	if (!devptr)
187 		return -ENOMEM;
188 
189 	spin_lock_init(&devptr->scoop_lock);
190 
191 	inf = pdev->dev.platform_data;
192 	devptr->base = ioremap(mem->start, resource_size(mem));
193 
194 	if (!devptr->base) {
195 		ret = -ENOMEM;
196 		goto err_ioremap;
197 	}
198 
199 	platform_set_drvdata(pdev, devptr);
200 
201 	printk("Sharp Scoop Device found at 0x%08x -> 0x%8p\n",(unsigned int)mem->start, devptr->base);
202 
203 	iowrite16(0x0140, devptr->base + SCOOP_MCR);
204 	reset_scoop(&pdev->dev);
205 	iowrite16(0x0000, devptr->base + SCOOP_CPR);
206 	iowrite16(inf->io_dir & 0xffff, devptr->base + SCOOP_GPCR);
207 	iowrite16(inf->io_out & 0xffff, devptr->base + SCOOP_GPWR);
208 
209 	devptr->suspend_clr = inf->suspend_clr;
210 	devptr->suspend_set = inf->suspend_set;
211 
212 	devptr->gpio.base = -1;
213 
214 	if (inf->gpio_base != 0) {
215 		devptr->gpio.label = dev_name(&pdev->dev);
216 		devptr->gpio.base = inf->gpio_base;
217 		devptr->gpio.ngpio = 12; /* PA11 = 0, PA12 = 1, etc. up to PA22 = 11 */
218 		devptr->gpio.set = scoop_gpio_set;
219 		devptr->gpio.get = scoop_gpio_get;
220 		devptr->gpio.direction_input = scoop_gpio_direction_input;
221 		devptr->gpio.direction_output = scoop_gpio_direction_output;
222 
223 		ret = gpiochip_add_data(&devptr->gpio, devptr);
224 		if (ret)
225 			goto err_gpio;
226 	}
227 
228 	return 0;
229 
230 err_gpio:
231 	platform_set_drvdata(pdev, NULL);
232 err_ioremap:
233 	iounmap(devptr->base);
234 	kfree(devptr);
235 
236 	return ret;
237 }
238 
239 static int scoop_remove(struct platform_device *pdev)
240 {
241 	struct scoop_dev *sdev = platform_get_drvdata(pdev);
242 
243 	if (!sdev)
244 		return -EINVAL;
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 	return 0;
254 }
255 
256 static struct platform_driver scoop_driver = {
257 	.probe		= scoop_probe,
258 	.remove		= scoop_remove,
259 	.suspend	= scoop_suspend,
260 	.resume		= scoop_resume,
261 	.driver		= {
262 		.name	= "sharp-scoop",
263 	},
264 };
265 
266 static int __init scoop_init(void)
267 {
268 	return platform_driver_register(&scoop_driver);
269 }
270 
271 subsys_initcall(scoop_init);
272