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