This source file includes following definitions.
- i2c_pca_pf_readbyte8
- i2c_pca_pf_readbyte16
- i2c_pca_pf_readbyte32
- i2c_pca_pf_writebyte8
- i2c_pca_pf_writebyte16
- i2c_pca_pf_writebyte32
- i2c_pca_pf_waitforcompletion
- i2c_pca_pf_dummyreset
- i2c_pca_pf_resetchip
- i2c_pca_pf_handler
- i2c_pca_pf_probe
- i2c_pca_pf_remove
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11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/delay.h>
15 #include <linux/jiffies.h>
16 #include <linux/errno.h>
17 #include <linux/i2c.h>
18 #include <linux/interrupt.h>
19 #include <linux/platform_device.h>
20 #include <linux/i2c-algo-pca.h>
21 #include <linux/platform_data/i2c-pca-platform.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26
27 #include <asm/irq.h>
28
29 struct i2c_pca_pf_data {
30 void __iomem *reg_base;
31 int irq;
32 struct gpio_desc *gpio;
33 wait_queue_head_t wait;
34 struct i2c_adapter adap;
35 struct i2c_algo_pca_data algo_data;
36 unsigned long io_base;
37 unsigned long io_size;
38 };
39
40
41
42 static int i2c_pca_pf_readbyte8(void *pd, int reg)
43 {
44 struct i2c_pca_pf_data *i2c = pd;
45 return ioread8(i2c->reg_base + reg);
46 }
47
48 static int i2c_pca_pf_readbyte16(void *pd, int reg)
49 {
50 struct i2c_pca_pf_data *i2c = pd;
51 return ioread8(i2c->reg_base + reg * 2);
52 }
53
54 static int i2c_pca_pf_readbyte32(void *pd, int reg)
55 {
56 struct i2c_pca_pf_data *i2c = pd;
57 return ioread8(i2c->reg_base + reg * 4);
58 }
59
60 static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
61 {
62 struct i2c_pca_pf_data *i2c = pd;
63 iowrite8(val, i2c->reg_base + reg);
64 }
65
66 static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
67 {
68 struct i2c_pca_pf_data *i2c = pd;
69 iowrite8(val, i2c->reg_base + reg * 2);
70 }
71
72 static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
73 {
74 struct i2c_pca_pf_data *i2c = pd;
75 iowrite8(val, i2c->reg_base + reg * 4);
76 }
77
78
79 static int i2c_pca_pf_waitforcompletion(void *pd)
80 {
81 struct i2c_pca_pf_data *i2c = pd;
82 unsigned long timeout;
83 long ret;
84
85 if (i2c->irq) {
86 ret = wait_event_timeout(i2c->wait,
87 i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
88 & I2C_PCA_CON_SI, i2c->adap.timeout);
89 } else {
90
91 timeout = jiffies + i2c->adap.timeout;
92 do {
93 ret = time_before(jiffies, timeout);
94 if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
95 & I2C_PCA_CON_SI)
96 break;
97 udelay(100);
98 } while (ret);
99 }
100
101 return ret > 0;
102 }
103
104 static void i2c_pca_pf_dummyreset(void *pd)
105 {
106 struct i2c_pca_pf_data *i2c = pd;
107
108 dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
109 }
110
111 static void i2c_pca_pf_resetchip(void *pd)
112 {
113 struct i2c_pca_pf_data *i2c = pd;
114
115 gpiod_set_value(i2c->gpio, 1);
116 ndelay(100);
117 gpiod_set_value(i2c->gpio, 0);
118 }
119
120 static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
121 {
122 struct i2c_pca_pf_data *i2c = dev_id;
123
124 if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
125 return IRQ_NONE;
126
127 wake_up(&i2c->wait);
128
129 return IRQ_HANDLED;
130 }
131
132
133 static int i2c_pca_pf_probe(struct platform_device *pdev)
134 {
135 struct i2c_pca_pf_data *i2c;
136 struct resource *res;
137 struct i2c_pca9564_pf_platform_data *platform_data =
138 dev_get_platdata(&pdev->dev);
139 struct device_node *np = pdev->dev.of_node;
140 int ret = 0;
141 int irq;
142
143 irq = platform_get_irq_optional(pdev, 0);
144
145 if (irq < 0)
146 irq = 0;
147
148 i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
149 if (!i2c)
150 return -ENOMEM;
151
152 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
153 i2c->reg_base = devm_ioremap_resource(&pdev->dev, res);
154 if (IS_ERR(i2c->reg_base))
155 return PTR_ERR(i2c->reg_base);
156
157
158 init_waitqueue_head(&i2c->wait);
159
160 i2c->io_base = res->start;
161 i2c->io_size = resource_size(res);
162 i2c->irq = irq;
163
164 i2c->adap.nr = pdev->id;
165 i2c->adap.owner = THIS_MODULE;
166 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
167 "PCA9564/PCA9665 at 0x%08lx",
168 (unsigned long) res->start);
169 i2c->adap.algo_data = &i2c->algo_data;
170 i2c->adap.dev.parent = &pdev->dev;
171 i2c->adap.dev.of_node = np;
172
173 i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
174 if (IS_ERR(i2c->gpio))
175 return PTR_ERR(i2c->gpio);
176
177 i2c->adap.timeout = HZ;
178 ret = device_property_read_u32(&pdev->dev, "clock-frequency",
179 &i2c->algo_data.i2c_clock);
180 if (ret)
181 i2c->algo_data.i2c_clock = 59000;
182
183 if (platform_data) {
184 i2c->adap.timeout = platform_data->timeout;
185 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
186 }
187
188 i2c->algo_data.data = i2c;
189 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
190 if (i2c->gpio)
191 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
192 else
193 i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
194
195 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
196 case IORESOURCE_MEM_32BIT:
197 i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
198 i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
199 break;
200 case IORESOURCE_MEM_16BIT:
201 i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
202 i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
203 break;
204 case IORESOURCE_MEM_8BIT:
205 default:
206 i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
207 i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
208 break;
209 }
210
211 if (irq) {
212 ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
213 IRQF_TRIGGER_FALLING, pdev->name, i2c);
214 if (ret)
215 return ret;
216 }
217
218 ret = i2c_pca_add_numbered_bus(&i2c->adap);
219 if (ret)
220 return ret;
221
222 platform_set_drvdata(pdev, i2c);
223
224 dev_info(&pdev->dev, "registered.\n");
225
226 return 0;
227 }
228
229 static int i2c_pca_pf_remove(struct platform_device *pdev)
230 {
231 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
232
233 i2c_del_adapter(&i2c->adap);
234
235 return 0;
236 }
237
238 #ifdef CONFIG_OF
239 static const struct of_device_id i2c_pca_of_match_table[] = {
240 { .compatible = "nxp,pca9564" },
241 { .compatible = "nxp,pca9665" },
242 {},
243 };
244 MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
245 #endif
246
247 static struct platform_driver i2c_pca_pf_driver = {
248 .probe = i2c_pca_pf_probe,
249 .remove = i2c_pca_pf_remove,
250 .driver = {
251 .name = "i2c-pca-platform",
252 .of_match_table = of_match_ptr(i2c_pca_of_match_table),
253 },
254 };
255
256 module_platform_driver(i2c_pca_pf_driver);
257
258 MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
259 MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
260 MODULE_LICENSE("GPL");