1
2
3
4
5
6
7
8
9
10
11
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/delay.h>
17#include <linux/jiffies.h>
18#include <linux/errno.h>
19#include <linux/i2c.h>
20#include <linux/interrupt.h>
21#include <linux/platform_device.h>
22#include <linux/i2c-algo-pca.h>
23#include <linux/i2c-pca-platform.h>
24#include <linux/gpio.h>
25#include <linux/io.h>
26
27#include <asm/irq.h>
28
29struct i2c_pca_pf_data {
30 void __iomem *reg_base;
31 int irq;
32 int 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
42static 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
48static 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
54static 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
60static 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
66static 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
72static 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
79static 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
104static void i2c_pca_pf_dummyreset(void *pd)
105{
106 struct i2c_pca_pf_data *i2c = pd;
107 printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n",
108 i2c->adap.name);
109}
110
111static void i2c_pca_pf_resetchip(void *pd)
112{
113 struct i2c_pca_pf_data *i2c = pd;
114
115 gpio_set_value(i2c->gpio, 0);
116 ndelay(100);
117 gpio_set_value(i2c->gpio, 1);
118}
119
120static 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
133static 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 int ret = 0;
140 int irq;
141
142 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
143 irq = platform_get_irq(pdev, 0);
144
145
146 if (res == NULL) {
147 ret = -ENODEV;
148 goto e_print;
149 }
150
151 if (!request_mem_region(res->start, resource_size(res), res->name)) {
152 ret = -ENOMEM;
153 goto e_print;
154 }
155
156 i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
157 if (!i2c) {
158 ret = -ENOMEM;
159 goto e_alloc;
160 }
161
162 init_waitqueue_head(&i2c->wait);
163
164 i2c->reg_base = ioremap(res->start, resource_size(res));
165 if (!i2c->reg_base) {
166 ret = -ENOMEM;
167 goto e_remap;
168 }
169 i2c->io_base = res->start;
170 i2c->io_size = resource_size(res);
171 i2c->irq = irq;
172
173 i2c->adap.nr = pdev->id;
174 i2c->adap.owner = THIS_MODULE;
175 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
176 "PCA9564/PCA9665 at 0x%08lx",
177 (unsigned long) res->start);
178 i2c->adap.algo_data = &i2c->algo_data;
179 i2c->adap.dev.parent = &pdev->dev;
180
181 if (platform_data) {
182 i2c->adap.timeout = platform_data->timeout;
183 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
184 i2c->gpio = platform_data->gpio;
185 } else {
186 i2c->adap.timeout = HZ;
187 i2c->algo_data.i2c_clock = 59000;
188 i2c->gpio = -1;
189 }
190
191 i2c->algo_data.data = i2c;
192 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
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
212 if (i2c->gpio > -1) {
213 ret = gpio_request(i2c->gpio, i2c->adap.name);
214 if (ret == 0) {
215 gpio_direction_output(i2c->gpio, 1);
216 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
217 } else {
218 printk(KERN_WARNING "%s: Registering gpio failed!\n",
219 i2c->adap.name);
220 i2c->gpio = ret;
221 }
222 }
223
224 if (irq) {
225 ret = request_irq(irq, i2c_pca_pf_handler,
226 IRQF_TRIGGER_FALLING, pdev->name, i2c);
227 if (ret)
228 goto e_reqirq;
229 }
230
231 if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
232 ret = -ENODEV;
233 goto e_adapt;
234 }
235
236 platform_set_drvdata(pdev, i2c);
237
238 printk(KERN_INFO "%s registered.\n", i2c->adap.name);
239
240 return 0;
241
242e_adapt:
243 if (irq)
244 free_irq(irq, i2c);
245e_reqirq:
246 if (i2c->gpio > -1)
247 gpio_free(i2c->gpio);
248
249 iounmap(i2c->reg_base);
250e_remap:
251 kfree(i2c);
252e_alloc:
253 release_mem_region(res->start, resource_size(res));
254e_print:
255 printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
256 return ret;
257}
258
259static int i2c_pca_pf_remove(struct platform_device *pdev)
260{
261 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
262
263 i2c_del_adapter(&i2c->adap);
264
265 if (i2c->irq)
266 free_irq(i2c->irq, i2c);
267
268 if (i2c->gpio > -1)
269 gpio_free(i2c->gpio);
270
271 iounmap(i2c->reg_base);
272 release_mem_region(i2c->io_base, i2c->io_size);
273 kfree(i2c);
274
275 return 0;
276}
277
278static struct platform_driver i2c_pca_pf_driver = {
279 .probe = i2c_pca_pf_probe,
280 .remove = i2c_pca_pf_remove,
281 .driver = {
282 .name = "i2c-pca-platform",
283 },
284};
285
286module_platform_driver(i2c_pca_pf_driver);
287
288MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
289MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
290MODULE_LICENSE("GPL");
291
