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21#include <linux/kernel.h>
22#include <linux/ioport.h>
23#include <linux/module.h>
24#include <linux/moduleparam.h>
25#include <linux/delay.h>
26#include <linux/jiffies.h>
27#include <linux/init.h>
28#include <linux/interrupt.h>
29#include <linux/wait.h>
30#include <linux/isa.h>
31#include <linux/i2c.h>
32#include <linux/i2c-algo-pca.h>
33#include <linux/io.h>
34
35#include <asm/irq.h>
36
37#define DRIVER "i2c-pca-isa"
38#define IO_SIZE 4
39
40static unsigned long base;
41static int irq = -1;
42
43
44
45static int clock = 59000;
46
47static struct i2c_adapter pca_isa_ops;
48static wait_queue_head_t pca_wait;
49
50static void pca_isa_writebyte(void *pd, int reg, int val)
51{
52#ifdef DEBUG_IO
53 static char *names[] = { "T/O", "DAT", "ADR", "CON" };
54 printk(KERN_DEBUG "*** write %s at %#lx <= %#04x\n", names[reg],
55 base+reg, val);
56#endif
57 outb(val, base+reg);
58}
59
60static int pca_isa_readbyte(void *pd, int reg)
61{
62 int res = inb(base+reg);
63#ifdef DEBUG_IO
64 {
65 static char *names[] = { "STA", "DAT", "ADR", "CON" };
66 printk(KERN_DEBUG "*** read %s => %#04x\n", names[reg], res);
67 }
68#endif
69 return res;
70}
71
72static int pca_isa_waitforcompletion(void *pd)
73{
74 unsigned long timeout;
75 long ret;
76
77 if (irq > -1) {
78 ret = wait_event_timeout(pca_wait,
79 pca_isa_readbyte(pd, I2C_PCA_CON)
80 & I2C_PCA_CON_SI, pca_isa_ops.timeout);
81 } else {
82
83 timeout = jiffies + pca_isa_ops.timeout;
84 do {
85 ret = time_before(jiffies, timeout);
86 if (pca_isa_readbyte(pd, I2C_PCA_CON)
87 & I2C_PCA_CON_SI)
88 break;
89 udelay(100);
90 } while (ret);
91 }
92
93 return ret > 0;
94}
95
96static void pca_isa_resetchip(void *pd)
97{
98
99 printk(KERN_WARNING DRIVER ": Haven't figured out how to do a reset yet\n");
100}
101
102static irqreturn_t pca_handler(int this_irq, void *dev_id) {
103 wake_up(&pca_wait);
104 return IRQ_HANDLED;
105}
106
107static struct i2c_algo_pca_data pca_isa_data = {
108
109 .write_byte = pca_isa_writebyte,
110 .read_byte = pca_isa_readbyte,
111 .wait_for_completion = pca_isa_waitforcompletion,
112 .reset_chip = pca_isa_resetchip,
113};
114
115static struct i2c_adapter pca_isa_ops = {
116 .owner = THIS_MODULE,
117 .algo_data = &pca_isa_data,
118 .name = "PCA9564/PCA9665 ISA Adapter",
119 .timeout = HZ,
120};
121
122static int __devinit pca_isa_match(struct device *dev, unsigned int id)
123{
124 int match = base != 0;
125
126 if (match) {
127 if (irq <= -1)
128 dev_warn(dev, "Using polling mode (specify irq)\n");
129 } else
130 dev_err(dev, "Please specify I/O base\n");
131
132 return match;
133}
134
135static int __devinit pca_isa_probe(struct device *dev, unsigned int id)
136{
137 init_waitqueue_head(&pca_wait);
138
139 dev_info(dev, "i/o base %#08lx. irq %d\n", base, irq);
140
141#ifdef CONFIG_PPC
142 if (check_legacy_ioport(base)) {
143 dev_err(dev, "I/O address %#08lx is not available\n", base);
144 goto out;
145 }
146#endif
147
148 if (!request_region(base, IO_SIZE, "i2c-pca-isa")) {
149 dev_err(dev, "I/O address %#08lx is in use\n", base);
150 goto out;
151 }
152
153 if (irq > -1) {
154 if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) {
155 dev_err(dev, "Request irq%d failed\n", irq);
156 goto out_region;
157 }
158 }
159
160 pca_isa_data.i2c_clock = clock;
161 if (i2c_pca_add_bus(&pca_isa_ops) < 0) {
162 dev_err(dev, "Failed to add i2c bus\n");
163 goto out_irq;
164 }
165
166 return 0;
167
168 out_irq:
169 if (irq > -1)
170 free_irq(irq, &pca_isa_ops);
171 out_region:
172 release_region(base, IO_SIZE);
173 out:
174 return -ENODEV;
175}
176
177static int __devexit pca_isa_remove(struct device *dev, unsigned int id)
178{
179 i2c_del_adapter(&pca_isa_ops);
180
181 if (irq > -1) {
182 disable_irq(irq);
183 free_irq(irq, &pca_isa_ops);
184 }
185 release_region(base, IO_SIZE);
186
187 return 0;
188}
189
190static struct isa_driver pca_isa_driver = {
191 .match = pca_isa_match,
192 .probe = pca_isa_probe,
193 .remove = __devexit_p(pca_isa_remove),
194 .driver = {
195 .owner = THIS_MODULE,
196 .name = DRIVER,
197 }
198};
199
200static int __init pca_isa_init(void)
201{
202 return isa_register_driver(&pca_isa_driver, 1);
203}
204
205static void __exit pca_isa_exit(void)
206{
207 isa_unregister_driver(&pca_isa_driver);
208}
209
210MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
211MODULE_DESCRIPTION("ISA base PCA9564/PCA9665 driver");
212MODULE_LICENSE("GPL");
213
214module_param(base, ulong, 0);
215MODULE_PARM_DESC(base, "I/O base address");
216
217module_param(irq, int, 0);
218MODULE_PARM_DESC(irq, "IRQ");
219module_param(clock, int, 0);
220MODULE_PARM_DESC(clock, "Clock rate in hertz.\n\t\t"
221 "For PCA9564: 330000,288000,217000,146000,"
222 "88000,59000,44000,36000\n"
223 "\t\tFor PCA9665:\tStandard: 60300 - 100099\n"
224 "\t\t\t\tFast: 100100 - 400099\n"
225 "\t\t\t\tFast+: 400100 - 10000099\n"
226 "\t\t\t\tTurbo: Up to 1265800");
227
228module_init(pca_isa_init);
229module_exit(pca_isa_exit);
230
