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13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/delay.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
26#include <asm/irq.h>
27#include <asm/io.h>
28
29#define res_len(r) ((r)->end - (r)->start + 1)
30
31struct i2c_pca_pf_data {
32 void __iomem *reg_base;
33 int irq;
34 int gpio;
35 wait_queue_head_t wait;
36 struct i2c_adapter adap;
37 struct i2c_algo_pca_data algo_data;
38 unsigned long io_base;
39 unsigned long io_size;
40};
41
42
43
44static int i2c_pca_pf_readbyte8(void *pd, int reg)
45{
46 struct i2c_pca_pf_data *i2c = pd;
47 return ioread8(i2c->reg_base + reg);
48}
49
50static int i2c_pca_pf_readbyte16(void *pd, int reg)
51{
52 struct i2c_pca_pf_data *i2c = pd;
53 return ioread8(i2c->reg_base + reg * 2);
54}
55
56static int i2c_pca_pf_readbyte32(void *pd, int reg)
57{
58 struct i2c_pca_pf_data *i2c = pd;
59 return ioread8(i2c->reg_base + reg * 4);
60}
61
62static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
63{
64 struct i2c_pca_pf_data *i2c = pd;
65 iowrite8(val, i2c->reg_base + reg);
66}
67
68static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
69{
70 struct i2c_pca_pf_data *i2c = pd;
71 iowrite8(val, i2c->reg_base + reg * 2);
72}
73
74static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
75{
76 struct i2c_pca_pf_data *i2c = pd;
77 iowrite8(val, i2c->reg_base + reg * 4);
78}
79
80
81static int i2c_pca_pf_waitforcompletion(void *pd)
82{
83 struct i2c_pca_pf_data *i2c = pd;
84 int ret = 0;
85
86 if (i2c->irq) {
87 ret = wait_event_interruptible(i2c->wait,
88 i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
89 & I2C_PCA_CON_SI);
90 } else {
91
92
93
94
95
96 while ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
97 & I2C_PCA_CON_SI) == 0)
98 udelay(100);
99 }
100
101 return ret;
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_interruptible(&i2c->wait);
128
129 return IRQ_HANDLED;
130}
131
132
133static int __devinit 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 pdev->dev.platform_data;
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, res_len(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, res_len(res));
165 if (!i2c->reg_base) {
166 ret = -ENOMEM;
167 goto e_remap;
168 }
169 i2c->io_base = res->start;
170 i2c->io_size = res_len(res);
171 i2c->irq = irq;
172
173 i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
174 i2c->adap.owner = THIS_MODULE;
175 snprintf(i2c->adap.name, sizeof(i2c->adap.name), "PCA9564 at 0x%08lx",
176 (unsigned long) res->start);
177 i2c->adap.algo_data = &i2c->algo_data;
178 i2c->adap.dev.parent = &pdev->dev;
179 i2c->adap.timeout = platform_data->timeout;
180
181 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
182 i2c->algo_data.data = i2c;
183
184 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
185 case IORESOURCE_MEM_32BIT:
186 i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
187 i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
188 break;
189 case IORESOURCE_MEM_16BIT:
190 i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
191 i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
192 break;
193 case IORESOURCE_MEM_8BIT:
194 default:
195 i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
196 i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
197 break;
198 }
199
200 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
201
202 i2c->gpio = platform_data->gpio;
203 i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
204
205
206 if (i2c->gpio > -1) {
207 ret = gpio_request(i2c->gpio, i2c->adap.name);
208 if (ret == 0) {
209 gpio_direction_output(i2c->gpio, 1);
210 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
211 } else {
212 printk(KERN_WARNING "%s: Registering gpio failed!\n",
213 i2c->adap.name);
214 i2c->gpio = ret;
215 }
216 }
217
218 if (irq) {
219 ret = request_irq(irq, i2c_pca_pf_handler,
220 IRQF_TRIGGER_FALLING, i2c->adap.name, i2c);
221 if (ret)
222 goto e_reqirq;
223 }
224
225 if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
226 ret = -ENODEV;
227 goto e_adapt;
228 }
229
230 platform_set_drvdata(pdev, i2c);
231
232 printk(KERN_INFO "%s registered.\n", i2c->adap.name);
233
234 return 0;
235
236e_adapt:
237 if (irq)
238 free_irq(irq, i2c);
239e_reqirq:
240 if (i2c->gpio > -1)
241 gpio_free(i2c->gpio);
242
243 iounmap(i2c->reg_base);
244e_remap:
245 kfree(i2c);
246e_alloc:
247 release_mem_region(res->start, res_len(res));
248e_print:
249 printk(KERN_ERR "Registering PCA9564 FAILED! (%d)\n", ret);
250 return ret;
251}
252
253static int __devexit i2c_pca_pf_remove(struct platform_device *pdev)
254{
255 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
256 platform_set_drvdata(pdev, NULL);
257
258 i2c_del_adapter(&i2c->adap);
259
260 if (i2c->irq)
261 free_irq(i2c->irq, i2c);
262
263 if (i2c->gpio > -1)
264 gpio_free(i2c->gpio);
265
266 iounmap(i2c->reg_base);
267 release_mem_region(i2c->io_base, i2c->io_size);
268 kfree(i2c);
269
270 return 0;
271}
272
273static struct platform_driver i2c_pca_pf_driver = {
274 .probe = i2c_pca_pf_probe,
275 .remove = __devexit_p(i2c_pca_pf_remove),
276 .driver = {
277 .name = "i2c-pca-platform",
278 .owner = THIS_MODULE,
279 },
280};
281
282static int __init i2c_pca_pf_init(void)
283{
284 return platform_driver_register(&i2c_pca_pf_driver);
285}
286
287static void __exit i2c_pca_pf_exit(void)
288{
289 platform_driver_unregister(&i2c_pca_pf_driver);
290}
291
292MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
293MODULE_DESCRIPTION("I2C-PCA9564 platform driver");
294MODULE_LICENSE("GPL");
295
296module_init(i2c_pca_pf_init);
297module_exit(i2c_pca_pf_exit);
298
299
