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gpio-da9052.c
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1 /*
2  * GPIO Driver for Dialog DA9052 PMICs.
3  *
4  * Copyright(c) 2011 Dialog Semiconductor Ltd.
5  *
6  * Author: David Dajun Chen <[email protected]>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the
10  * Free Software Foundation; either version 2 of the License, or (at your
11  * option) any later version.
12  *
13  */
14 #include <linux/module.h>
15 #include <linux/fs.h>
16 #include <linux/uaccess.h>
17 #include <linux/platform_device.h>
18 #include <linux/gpio.h>
19 #include <linux/syscalls.h>
20 #include <linux/seq_file.h>
21 
22 #include <linux/mfd/da9052/da9052.h>
23 #include <linux/mfd/da9052/reg.h>
24 #include <linux/mfd/da9052/pdata.h>
25 
26 #define DA9052_INPUT 1
27 #define DA9052_OUTPUT_OPENDRAIN 2
28 #define DA9052_OUTPUT_PUSHPULL 3
29 
30 #define DA9052_SUPPLY_VDD_IO1 0
31 
32 #define DA9052_DEBOUNCING_OFF 0
33 #define DA9052_DEBOUNCING_ON 1
34 
35 #define DA9052_OUTPUT_LOWLEVEL 0
36 
37 #define DA9052_ACTIVE_LOW 0
38 #define DA9052_ACTIVE_HIGH 1
39 
40 #define DA9052_GPIO_MAX_PORTS_PER_REGISTER 8
41 #define DA9052_GPIO_SHIFT_COUNT(no) (no%8)
42 #define DA9052_GPIO_MASK_UPPER_NIBBLE 0xF0
43 #define DA9052_GPIO_MASK_LOWER_NIBBLE 0x0F
44 #define DA9052_GPIO_NIBBLE_SHIFT 4
45 #define DA9052_IRQ_GPI0 16
46 #define DA9052_GPIO_ODD_SHIFT 7
47 #define DA9052_GPIO_EVEN_SHIFT 3
48 
49 struct da9052_gpio {
50  struct da9052 *da9052;
51  struct gpio_chip gp;
52 };
53 
54 static inline struct da9052_gpio *to_da9052_gpio(struct gpio_chip *chip)
55 {
56  return container_of(chip, struct da9052_gpio, gp);
57 }
58 
59 static unsigned char da9052_gpio_port_odd(unsigned offset)
60 {
61  return offset % 2;
62 }
63 
64 static int da9052_gpio_get(struct gpio_chip *gc, unsigned offset)
65 {
66  struct da9052_gpio *gpio = to_da9052_gpio(gc);
67  int da9052_port_direction = 0;
68  int ret;
69 
70  ret = da9052_reg_read(gpio->da9052,
71  DA9052_GPIO_0_1_REG + (offset >> 1));
72  if (ret < 0)
73  return ret;
74 
75  if (da9052_gpio_port_odd(offset)) {
76  da9052_port_direction = ret & DA9052_GPIO_ODD_PORT_PIN;
77  da9052_port_direction >>= 4;
78  } else {
79  da9052_port_direction = ret & DA9052_GPIO_EVEN_PORT_PIN;
80  }
81 
82  switch (da9052_port_direction) {
83  case DA9052_INPUT:
84  if (offset < DA9052_GPIO_MAX_PORTS_PER_REGISTER)
85  ret = da9052_reg_read(gpio->da9052,
86  DA9052_STATUS_C_REG);
87  else
88  ret = da9052_reg_read(gpio->da9052,
89  DA9052_STATUS_D_REG);
90  if (ret < 0)
91  return ret;
92  if (ret & (1 << DA9052_GPIO_SHIFT_COUNT(offset)))
93  return 1;
94  else
95  return 0;
96  case DA9052_OUTPUT_PUSHPULL:
97  if (da9052_gpio_port_odd(offset))
98  return ret & DA9052_GPIO_ODD_PORT_MODE;
99  else
100  return ret & DA9052_GPIO_EVEN_PORT_MODE;
101  default:
102  return -EINVAL;
103  }
104 }
105 
106 static void da9052_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
107 {
108  struct da9052_gpio *gpio = to_da9052_gpio(gc);
109  int ret;
110 
111  if (da9052_gpio_port_odd(offset)) {
112  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
113  DA9052_GPIO_0_1_REG,
114  DA9052_GPIO_ODD_PORT_MODE,
115  value << DA9052_GPIO_ODD_SHIFT);
116  if (ret != 0)
117  dev_err(gpio->da9052->dev,
118  "Failed to updated gpio odd reg,%d",
119  ret);
120  } else {
121  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
122  DA9052_GPIO_0_1_REG,
123  DA9052_GPIO_EVEN_PORT_MODE,
124  value << DA9052_GPIO_EVEN_SHIFT);
125  if (ret != 0)
126  dev_err(gpio->da9052->dev,
127  "Failed to updated gpio even reg,%d",
128  ret);
129  }
130 }
131 
132 static int da9052_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
133 {
134  struct da9052_gpio *gpio = to_da9052_gpio(gc);
135  unsigned char register_value;
136  int ret;
137 
138  /* Format: function - 2 bits type - 1 bit mode - 1 bit */
139  register_value = DA9052_INPUT | DA9052_ACTIVE_LOW << 2 |
140  DA9052_DEBOUNCING_ON << 3;
141 
142  if (da9052_gpio_port_odd(offset))
143  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
144  DA9052_GPIO_0_1_REG,
145  DA9052_GPIO_MASK_UPPER_NIBBLE,
146  (register_value <<
147  DA9052_GPIO_NIBBLE_SHIFT));
148  else
149  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
150  DA9052_GPIO_0_1_REG,
151  DA9052_GPIO_MASK_LOWER_NIBBLE,
152  register_value);
153 
154  return ret;
155 }
156 
157 static int da9052_gpio_direction_output(struct gpio_chip *gc,
158  unsigned offset, int value)
159 {
160  struct da9052_gpio *gpio = to_da9052_gpio(gc);
161  unsigned char register_value;
162  int ret;
163 
164  /* Format: Function - 2 bits Type - 1 bit Mode - 1 bit */
165  register_value = DA9052_OUTPUT_PUSHPULL | DA9052_SUPPLY_VDD_IO1 << 2 |
166  value << 3;
167 
168  if (da9052_gpio_port_odd(offset))
169  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
170  DA9052_GPIO_0_1_REG,
171  DA9052_GPIO_MASK_UPPER_NIBBLE,
172  (register_value <<
173  DA9052_GPIO_NIBBLE_SHIFT));
174  else
175  ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
176  DA9052_GPIO_0_1_REG,
177  DA9052_GPIO_MASK_LOWER_NIBBLE,
178  register_value);
179 
180  return ret;
181 }
182 
183 static int da9052_gpio_to_irq(struct gpio_chip *gc, u32 offset)
184 {
185  struct da9052_gpio *gpio = to_da9052_gpio(gc);
186  struct da9052 *da9052 = gpio->da9052;
187 
188  return da9052->irq_base + DA9052_IRQ_GPI0 + offset;
189 }
190 
191 static struct gpio_chip reference_gp __devinitdata = {
192  .label = "da9052-gpio",
193  .owner = THIS_MODULE,
194  .get = da9052_gpio_get,
195  .set = da9052_gpio_set,
196  .direction_input = da9052_gpio_direction_input,
197  .direction_output = da9052_gpio_direction_output,
198  .to_irq = da9052_gpio_to_irq,
199  .can_sleep = 1,
200  .ngpio = 16,
201  .base = -1,
202 };
203 
204 static int __devinit da9052_gpio_probe(struct platform_device *pdev)
205 {
206  struct da9052_gpio *gpio;
207  struct da9052_pdata *pdata;
208  int ret;
209 
210  gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
211  if (gpio == NULL)
212  return -ENOMEM;
213 
214  gpio->da9052 = dev_get_drvdata(pdev->dev.parent);
215  pdata = gpio->da9052->dev->platform_data;
216 
217  gpio->gp = reference_gp;
218  if (pdata && pdata->gpio_base)
219  gpio->gp.base = pdata->gpio_base;
220 
221  ret = gpiochip_add(&gpio->gp);
222  if (ret < 0) {
223  dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
224  return ret;
225  }
226 
227  platform_set_drvdata(pdev, gpio);
228 
229  return 0;
230 }
231 
232 static int __devexit da9052_gpio_remove(struct platform_device *pdev)
233 {
234  struct da9052_gpio *gpio = platform_get_drvdata(pdev);
235 
236  return gpiochip_remove(&gpio->gp);
237 }
238 
239 static struct platform_driver da9052_gpio_driver = {
240  .probe = da9052_gpio_probe,
241  .remove = __devexit_p(da9052_gpio_remove),
242  .driver = {
243  .name = "da9052-gpio",
244  .owner = THIS_MODULE,
245  },
246 };
247 
248 module_platform_driver(da9052_gpio_driver);
249 
250 MODULE_AUTHOR("David Dajun Chen <[email protected]>");
251 MODULE_DESCRIPTION("DA9052 GPIO Device Driver");
252 MODULE_LICENSE("GPL");
253 MODULE_ALIAS("platform:da9052-gpio");
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