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10#include <linux/bits.h>
11#include <linux/gpio/driver.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/mfd/syscon.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/platform_device.h>
18#include <linux/regmap.h>
19
20#define PIOBU_NUM 8
21#define PIOBU_REG_SIZE 4
22
23
24
25
26
27
28#define PIOBU_BMPR 0x7C
29#define PIOBU_NMPR 0x80
30#define PIOBU_WKPR 0x90
31
32#define PIOBU_BASE 0x18
33
34#define PIOBU_DET_OFFSET 16
35
36
37#define PIOBU_DIRECTION BIT(8)
38#define PIOBU_OUT BIT(8)
39#define PIOBU_IN 0
40
41#define PIOBU_SOD BIT(9)
42#define PIOBU_PDS BIT(10)
43
44#define PIOBU_HIGH BIT(9)
45#define PIOBU_LOW 0
46
47struct sama5d2_piobu {
48 struct gpio_chip chip;
49 struct regmap *regmap;
50};
51
52
53
54
55
56
57
58static int sama5d2_piobu_setup_pin(struct gpio_chip *chip, unsigned int pin)
59{
60 int ret;
61 struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
62 chip);
63 unsigned int mask = BIT(PIOBU_DET_OFFSET + pin);
64
65 ret = regmap_update_bits(piobu->regmap, PIOBU_BMPR, mask, 0);
66 if (ret)
67 return ret;
68
69 ret = regmap_update_bits(piobu->regmap, PIOBU_NMPR, mask, 0);
70 if (ret)
71 return ret;
72
73 return regmap_update_bits(piobu->regmap, PIOBU_WKPR, mask, 0);
74}
75
76
77
78
79static int sama5d2_piobu_write_value(struct gpio_chip *chip, unsigned int pin,
80 unsigned int mask, unsigned int value)
81{
82 int reg;
83 struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
84 chip);
85
86 reg = PIOBU_BASE + pin * PIOBU_REG_SIZE;
87
88 return regmap_update_bits(piobu->regmap, reg, mask, value);
89}
90
91
92
93
94
95static int sama5d2_piobu_read_value(struct gpio_chip *chip, unsigned int pin,
96 unsigned int mask)
97{
98 struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
99 chip);
100 unsigned int val, reg;
101 int ret;
102
103 reg = PIOBU_BASE + pin * PIOBU_REG_SIZE;
104 ret = regmap_read(piobu->regmap, reg, &val);
105 if (ret < 0)
106 return ret;
107
108 return val & mask;
109}
110
111
112
113
114static int sama5d2_piobu_get_direction(struct gpio_chip *chip,
115 unsigned int pin)
116{
117 int ret = sama5d2_piobu_read_value(chip, pin, PIOBU_DIRECTION);
118
119 if (ret < 0)
120 return ret;
121
122 return (ret == PIOBU_IN) ? GPIO_LINE_DIRECTION_IN :
123 GPIO_LINE_DIRECTION_OUT;
124}
125
126
127
128
129static int sama5d2_piobu_direction_input(struct gpio_chip *chip,
130 unsigned int pin)
131{
132 return sama5d2_piobu_write_value(chip, pin, PIOBU_DIRECTION, PIOBU_IN);
133}
134
135
136
137
138static int sama5d2_piobu_direction_output(struct gpio_chip *chip,
139 unsigned int pin, int value)
140{
141 unsigned int val = PIOBU_OUT;
142
143 if (value)
144 val |= PIOBU_HIGH;
145
146 return sama5d2_piobu_write_value(chip, pin, PIOBU_DIRECTION | PIOBU_SOD,
147 val);
148}
149
150
151
152
153static int sama5d2_piobu_get(struct gpio_chip *chip, unsigned int pin)
154{
155
156 int ret = sama5d2_piobu_get_direction(chip, pin);
157
158 if (ret == GPIO_LINE_DIRECTION_IN)
159 ret = sama5d2_piobu_read_value(chip, pin, PIOBU_PDS);
160 else if (ret == GPIO_LINE_DIRECTION_OUT)
161 ret = sama5d2_piobu_read_value(chip, pin, PIOBU_SOD);
162
163 if (ret < 0)
164 return ret;
165
166 return !!ret;
167}
168
169
170
171
172static void sama5d2_piobu_set(struct gpio_chip *chip, unsigned int pin,
173 int value)
174{
175 if (!value)
176 value = PIOBU_LOW;
177 else
178 value = PIOBU_HIGH;
179
180 sama5d2_piobu_write_value(chip, pin, PIOBU_SOD, value);
181}
182
183static int sama5d2_piobu_probe(struct platform_device *pdev)
184{
185 struct sama5d2_piobu *piobu;
186 int ret, i;
187
188 piobu = devm_kzalloc(&pdev->dev, sizeof(*piobu), GFP_KERNEL);
189 if (!piobu)
190 return -ENOMEM;
191
192 platform_set_drvdata(pdev, piobu);
193 piobu->chip.label = pdev->name;
194 piobu->chip.parent = &pdev->dev;
195 piobu->chip.of_node = pdev->dev.of_node;
196 piobu->chip.owner = THIS_MODULE,
197 piobu->chip.get_direction = sama5d2_piobu_get_direction,
198 piobu->chip.direction_input = sama5d2_piobu_direction_input,
199 piobu->chip.direction_output = sama5d2_piobu_direction_output,
200 piobu->chip.get = sama5d2_piobu_get,
201 piobu->chip.set = sama5d2_piobu_set,
202 piobu->chip.base = -1,
203 piobu->chip.ngpio = PIOBU_NUM,
204 piobu->chip.can_sleep = 0,
205
206 piobu->regmap = syscon_node_to_regmap(pdev->dev.of_node);
207 if (IS_ERR(piobu->regmap)) {
208 dev_err(&pdev->dev, "Failed to get syscon regmap %ld\n",
209 PTR_ERR(piobu->regmap));
210 return PTR_ERR(piobu->regmap);
211 }
212
213 ret = devm_gpiochip_add_data(&pdev->dev, &piobu->chip, piobu);
214 if (ret) {
215 dev_err(&pdev->dev, "Failed to add gpiochip %d\n", ret);
216 return ret;
217 }
218
219 for (i = 0; i < PIOBU_NUM; ++i) {
220 ret = sama5d2_piobu_setup_pin(&piobu->chip, i);
221 if (ret) {
222 dev_err(&pdev->dev, "Failed to setup pin: %d %d\n",
223 i, ret);
224 return ret;
225 }
226 }
227
228 return 0;
229}
230
231static const struct of_device_id sama5d2_piobu_ids[] = {
232 { .compatible = "atmel,sama5d2-secumod" },
233 {},
234};
235MODULE_DEVICE_TABLE(of, sama5d2_piobu_ids);
236
237static struct platform_driver sama5d2_piobu_driver = {
238 .driver = {
239 .name = "sama5d2-piobu",
240 .of_match_table = of_match_ptr(sama5d2_piobu_ids)
241 },
242 .probe = sama5d2_piobu_probe,
243};
244
245module_platform_driver(sama5d2_piobu_driver);
246
247MODULE_LICENSE("GPL v2");
248MODULE_DESCRIPTION("SAMA5D2 PIOBU controller driver");
249MODULE_AUTHOR("Andrei Stefanescu <andrei.stefanescu@microchip.com>");
250
