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