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gpio-au1300.h
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1 /*
2  * gpio-au1300.h -- GPIO control for Au1300 GPIC and compatibles.
3  *
4  * Copyright (c) 2009-2011 Manuel Lauss <[email protected]>
5  */
6 
7 #ifndef _GPIO_AU1300_H_
8 #define _GPIO_AU1300_H_
9 
10 #include <asm/addrspace.h>
11 #include <asm/io.h>
12 #include <asm/mach-au1x00/au1000.h>
13 
14 struct gpio;
15 struct gpio_chip;
16 
17 /* with the current GPIC design, up to 128 GPIOs are possible.
18  * The only implementation so far is in the Au1300, which has 75 externally
19  * available GPIOs.
20  */
21 #define AU1300_GPIO_BASE 0
22 #define AU1300_GPIO_NUM 75
23 #define AU1300_GPIO_MAX (AU1300_GPIO_BASE + AU1300_GPIO_NUM - 1)
24 
25 #define AU1300_GPIC_ADDR \
26  (void __iomem *)KSEG1ADDR(AU1300_GPIC_PHYS_ADDR)
27 
28 static inline int au1300_gpio_get_value(unsigned int gpio)
29 {
30  void __iomem *roff = AU1300_GPIC_ADDR;
31  int bit;
32 
33  gpio -= AU1300_GPIO_BASE;
34  roff += GPIC_GPIO_BANKOFF(gpio);
35  bit = GPIC_GPIO_TO_BIT(gpio);
36  return __raw_readl(roff + AU1300_GPIC_PINVAL) & bit;
37 }
38 
39 static inline int au1300_gpio_direction_input(unsigned int gpio)
40 {
41  void __iomem *roff = AU1300_GPIC_ADDR;
42  unsigned long bit;
43 
44  gpio -= AU1300_GPIO_BASE;
45 
46  roff += GPIC_GPIO_BANKOFF(gpio);
47  bit = GPIC_GPIO_TO_BIT(gpio);
48  __raw_writel(bit, roff + AU1300_GPIC_DEVCLR);
49  wmb();
50 
51  return 0;
52 }
53 
54 static inline int au1300_gpio_set_value(unsigned int gpio, int v)
55 {
56  void __iomem *roff = AU1300_GPIC_ADDR;
57  unsigned long bit;
58 
59  gpio -= AU1300_GPIO_BASE;
60 
61  roff += GPIC_GPIO_BANKOFF(gpio);
62  bit = GPIC_GPIO_TO_BIT(gpio);
63  __raw_writel(bit, roff + (v ? AU1300_GPIC_PINVAL
65  wmb();
66 
67  return 0;
68 }
69 
70 static inline int au1300_gpio_direction_output(unsigned int gpio, int v)
71 {
72  /* hw switches to output automatically */
73  return au1300_gpio_set_value(gpio, v);
74 }
75 
76 static inline int au1300_gpio_to_irq(unsigned int gpio)
77 {
78  return AU1300_FIRST_INT + (gpio - AU1300_GPIO_BASE);
79 }
80 
81 static inline int au1300_irq_to_gpio(unsigned int irq)
82 {
83  return (irq - AU1300_FIRST_INT) + AU1300_GPIO_BASE;
84 }
85 
86 static inline int au1300_gpio_is_valid(unsigned int gpio)
87 {
88  int ret;
89 
90  switch (alchemy_get_cputype()) {
91  case ALCHEMY_CPU_AU1300:
92  ret = ((gpio >= AU1300_GPIO_BASE) && (gpio <= AU1300_GPIO_MAX));
93  break;
94  default:
95  ret = 0;
96  }
97  return ret;
98 }
99 
100 static inline int au1300_gpio_cansleep(unsigned int gpio)
101 {
102  return 0;
103 }
104 
105 /* hardware remembers gpio 0-63 levels on powerup */
106 static inline int au1300_gpio_getinitlvl(unsigned int gpio)
107 {
108  void __iomem *roff = AU1300_GPIC_ADDR;
109  unsigned long v;
110 
111  if (unlikely(gpio > 63))
112  return 0;
113  else if (gpio > 31) {
114  gpio -= 32;
115  roff += 4;
116  }
117 
118  v = __raw_readl(roff + AU1300_GPIC_RSTVAL);
119  return (v >> gpio) & 1;
120 }
121 
122 /**********************************************************************/
123 
124 /* Linux gpio framework integration.
125 *
126 * 4 use cases of Alchemy GPIOS:
127 *(1) GPIOLIB=y, ALCHEMY_GPIO_INDIRECT=y:
128 * Board must register gpiochips.
129 *(2) GPIOLIB=y, ALCHEMY_GPIO_INDIRECT=n:
130 * A gpiochip for the 75 GPIOs is registered.
131 *
132 *(3) GPIOLIB=n, ALCHEMY_GPIO_INDIRECT=y:
133 * the boards' gpio.h must provide the linux gpio wrapper functions,
134 *
135 *(4) GPIOLIB=n, ALCHEMY_GPIO_INDIRECT=n:
136 * inlinable gpio functions are provided which enable access to the
137 * Au1300 gpios only by using the numbers straight out of the data-
138 * sheets.
139 
140 * Cases 1 and 3 are intended for boards which want to provide their own
141 * GPIO namespace and -operations (i.e. for example you have 8 GPIOs
142 * which are in part provided by spare Au1300 GPIO pins and in part by
143 * an external FPGA but you still want them to be accssible in linux
144 * as gpio0-7. The board can of course use the alchemy_gpioX_* functions
145 * as required).
146 */
147 
148 #ifndef CONFIG_GPIOLIB
149 
150 #ifdef CONFIG_ALCHEMY_GPIOINT_AU1300
151 
152 #ifndef CONFIG_ALCHEMY_GPIO_INDIRECT /* case (4) */
153 
154 static inline int gpio_direction_input(unsigned int gpio)
155 {
156  return au1300_gpio_direction_input(gpio);
157 }
158 
159 static inline int gpio_direction_output(unsigned int gpio, int v)
160 {
161  return au1300_gpio_direction_output(gpio, v);
162 }
163 
164 static inline int gpio_get_value(unsigned int gpio)
165 {
166  return au1300_gpio_get_value(gpio);
167 }
168 
169 static inline void gpio_set_value(unsigned int gpio, int v)
170 {
171  au1300_gpio_set_value(gpio, v);
172 }
173 
174 static inline int gpio_get_value_cansleep(unsigned gpio)
175 {
176  return gpio_get_value(gpio);
177 }
178 
179 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
180 {
181  gpio_set_value(gpio, value);
182 }
183 
184 static inline int gpio_is_valid(unsigned int gpio)
185 {
186  return au1300_gpio_is_valid(gpio);
187 }
188 
189 static inline int gpio_cansleep(unsigned int gpio)
190 {
191  return au1300_gpio_cansleep(gpio);
192 }
193 
194 static inline int gpio_to_irq(unsigned int gpio)
195 {
196  return au1300_gpio_to_irq(gpio);
197 }
198 
199 static inline int irq_to_gpio(unsigned int irq)
200 {
201  return au1300_irq_to_gpio(irq);
202 }
203 
204 static inline int gpio_request(unsigned int gpio, const char *label)
205 {
206  return 0;
207 }
208 
209 static inline int gpio_request_one(unsigned gpio,
210  unsigned long flags, const char *label)
211 {
212  return 0;
213 }
214 
215 static inline int gpio_request_array(struct gpio *array, size_t num)
216 {
217  return 0;
218 }
219 
220 static inline void gpio_free(unsigned gpio)
221 {
222 }
223 
224 static inline void gpio_free_array(struct gpio *array, size_t num)
225 {
226 }
227 
228 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
229 {
230  return -ENOSYS;
231 }
232 
233 static inline void gpio_unexport(unsigned gpio)
234 {
235 }
236 
237 static inline int gpio_export(unsigned gpio, bool direction_may_change)
238 {
239  return -ENOSYS;
240 }
241 
242 static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
243 {
244  return -ENOSYS;
245 }
246 
247 static inline int gpio_export_link(struct device *dev, const char *name,
248  unsigned gpio)
249 {
250  return -ENOSYS;
251 }
252 
253 #endif /* !CONFIG_ALCHEMY_GPIO_INDIRECT */
254 
255 #endif /* CONFIG_ALCHEMY_GPIOINT_AU1300 */
256 
257 #endif /* CONFIG GPIOLIB */
258 
259 #endif /* _GPIO_AU1300_H_ */