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244fbbb8 WS |
1 | /* |
2 | * i2c_pca_platform.c | |
3 | * | |
4 | * Platform driver for the PCA9564 I2C controller. | |
5 | * | |
6 | * Copyright (C) 2008 Pengutronix | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | ||
12 | */ | |
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> | |
2378bc09 | 18 | #include <linux/jiffies.h> |
244fbbb8 WS |
19 | #include <linux/errno.h> |
20 | #include <linux/i2c.h> | |
21 | #include <linux/interrupt.h> | |
22 | #include <linux/platform_device.h> | |
23 | #include <linux/i2c-algo-pca.h> | |
24 | #include <linux/i2c-pca-platform.h> | |
25 | #include <linux/gpio.h> | |
26 | ||
27 | #include <asm/irq.h> | |
28 | #include <asm/io.h> | |
29 | ||
244fbbb8 WS |
30 | struct i2c_pca_pf_data { |
31 | void __iomem *reg_base; | |
32 | int irq; /* if 0, use polling */ | |
33 | int gpio; | |
34 | wait_queue_head_t wait; | |
35 | struct i2c_adapter adap; | |
36 | struct i2c_algo_pca_data algo_data; | |
37 | unsigned long io_base; | |
38 | unsigned long io_size; | |
39 | }; | |
40 | ||
41 | /* Read/Write functions for different register alignments */ | |
42 | ||
43 | static int i2c_pca_pf_readbyte8(void *pd, int reg) | |
44 | { | |
45 | struct i2c_pca_pf_data *i2c = pd; | |
46 | return ioread8(i2c->reg_base + reg); | |
47 | } | |
48 | ||
49 | static int i2c_pca_pf_readbyte16(void *pd, int reg) | |
50 | { | |
51 | struct i2c_pca_pf_data *i2c = pd; | |
52 | return ioread8(i2c->reg_base + reg * 2); | |
53 | } | |
54 | ||
55 | static int i2c_pca_pf_readbyte32(void *pd, int reg) | |
56 | { | |
57 | struct i2c_pca_pf_data *i2c = pd; | |
58 | return ioread8(i2c->reg_base + reg * 4); | |
59 | } | |
60 | ||
61 | static void i2c_pca_pf_writebyte8(void *pd, int reg, int val) | |
62 | { | |
63 | struct i2c_pca_pf_data *i2c = pd; | |
64 | iowrite8(val, i2c->reg_base + reg); | |
65 | } | |
66 | ||
67 | static void i2c_pca_pf_writebyte16(void *pd, int reg, int val) | |
68 | { | |
69 | struct i2c_pca_pf_data *i2c = pd; | |
70 | iowrite8(val, i2c->reg_base + reg * 2); | |
71 | } | |
72 | ||
73 | static void i2c_pca_pf_writebyte32(void *pd, int reg, int val) | |
74 | { | |
75 | struct i2c_pca_pf_data *i2c = pd; | |
76 | iowrite8(val, i2c->reg_base + reg * 4); | |
77 | } | |
78 | ||
79 | ||
80 | static int i2c_pca_pf_waitforcompletion(void *pd) | |
81 | { | |
82 | struct i2c_pca_pf_data *i2c = pd; | |
2378bc09 WS |
83 | long ret = ~0; |
84 | unsigned long timeout; | |
244fbbb8 WS |
85 | |
86 | if (i2c->irq) { | |
22f8b269 | 87 | ret = wait_event_timeout(i2c->wait, |
244fbbb8 | 88 | i2c->algo_data.read_byte(i2c, I2C_PCA_CON) |
2378bc09 | 89 | & I2C_PCA_CON_SI, i2c->adap.timeout); |
244fbbb8 | 90 | } else { |
2378bc09 WS |
91 | /* Do polling */ |
92 | timeout = jiffies + i2c->adap.timeout; | |
93 | while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) | |
244fbbb8 | 94 | & I2C_PCA_CON_SI) == 0) |
2378bc09 | 95 | && (ret = time_before(jiffies, timeout))) |
244fbbb8 WS |
96 | udelay(100); |
97 | } | |
98 | ||
2378bc09 | 99 | return ret > 0; |
244fbbb8 WS |
100 | } |
101 | ||
102 | static void i2c_pca_pf_dummyreset(void *pd) | |
103 | { | |
104 | struct i2c_pca_pf_data *i2c = pd; | |
105 | printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n", | |
106 | i2c->adap.name); | |
107 | } | |
108 | ||
109 | static void i2c_pca_pf_resetchip(void *pd) | |
110 | { | |
111 | struct i2c_pca_pf_data *i2c = pd; | |
112 | ||
113 | gpio_set_value(i2c->gpio, 0); | |
114 | ndelay(100); | |
115 | gpio_set_value(i2c->gpio, 1); | |
116 | } | |
117 | ||
118 | static 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 | ||
22f8b269 | 125 | wake_up(&i2c->wait); |
244fbbb8 WS |
126 | |
127 | return IRQ_HANDLED; | |
128 | } | |
129 | ||
130 | ||
131 | static int __devinit 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 | pdev->dev.platform_data; | |
137 | int ret = 0; | |
138 | int irq; | |
139 | ||
140 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
141 | irq = platform_get_irq(pdev, 0); | |
142 | /* If irq is 0, we do polling. */ | |
143 | ||
144 | if (res == NULL) { | |
145 | ret = -ENODEV; | |
146 | goto e_print; | |
147 | } | |
148 | ||
c6ffddea | 149 | if (!request_mem_region(res->start, resource_size(res), res->name)) { |
244fbbb8 WS |
150 | ret = -ENOMEM; |
151 | goto e_print; | |
152 | } | |
153 | ||
154 | i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL); | |
155 | if (!i2c) { | |
156 | ret = -ENOMEM; | |
157 | goto e_alloc; | |
158 | } | |
159 | ||
160 | init_waitqueue_head(&i2c->wait); | |
161 | ||
c6ffddea | 162 | i2c->reg_base = ioremap(res->start, resource_size(res)); |
244fbbb8 | 163 | if (!i2c->reg_base) { |
7650da02 | 164 | ret = -ENOMEM; |
244fbbb8 WS |
165 | goto e_remap; |
166 | } | |
167 | i2c->io_base = res->start; | |
c6ffddea | 168 | i2c->io_size = resource_size(res); |
244fbbb8 WS |
169 | i2c->irq = irq; |
170 | ||
171 | i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0; | |
172 | i2c->adap.owner = THIS_MODULE; | |
eff9ec95 MAC |
173 | snprintf(i2c->adap.name, sizeof(i2c->adap.name), |
174 | "PCA9564/PCA9665 at 0x%08lx", | |
175 | (unsigned long) res->start); | |
244fbbb8 WS |
176 | i2c->adap.algo_data = &i2c->algo_data; |
177 | i2c->adap.dev.parent = &pdev->dev; | |
244fbbb8 | 178 | |
6b110d13 WS |
179 | if (platform_data) { |
180 | i2c->adap.timeout = platform_data->timeout; | |
181 | i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed; | |
182 | i2c->gpio = platform_data->gpio; | |
183 | } else { | |
184 | i2c->adap.timeout = HZ; | |
185 | i2c->algo_data.i2c_clock = 59000; | |
186 | i2c->gpio = -1; | |
187 | } | |
188 | ||
244fbbb8 | 189 | i2c->algo_data.data = i2c; |
6b110d13 WS |
190 | i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion; |
191 | i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset; | |
244fbbb8 WS |
192 | |
193 | switch (res->flags & IORESOURCE_MEM_TYPE_MASK) { | |
194 | case IORESOURCE_MEM_32BIT: | |
195 | i2c->algo_data.write_byte = i2c_pca_pf_writebyte32; | |
196 | i2c->algo_data.read_byte = i2c_pca_pf_readbyte32; | |
197 | break; | |
198 | case IORESOURCE_MEM_16BIT: | |
199 | i2c->algo_data.write_byte = i2c_pca_pf_writebyte16; | |
200 | i2c->algo_data.read_byte = i2c_pca_pf_readbyte16; | |
201 | break; | |
202 | case IORESOURCE_MEM_8BIT: | |
203 | default: | |
204 | i2c->algo_data.write_byte = i2c_pca_pf_writebyte8; | |
205 | i2c->algo_data.read_byte = i2c_pca_pf_readbyte8; | |
206 | break; | |
207 | } | |
208 | ||
244fbbb8 WS |
209 | /* Use gpio_is_valid() when in mainline */ |
210 | if (i2c->gpio > -1) { | |
211 | ret = gpio_request(i2c->gpio, i2c->adap.name); | |
212 | if (ret == 0) { | |
213 | gpio_direction_output(i2c->gpio, 1); | |
214 | i2c->algo_data.reset_chip = i2c_pca_pf_resetchip; | |
215 | } else { | |
216 | printk(KERN_WARNING "%s: Registering gpio failed!\n", | |
217 | i2c->adap.name); | |
218 | i2c->gpio = ret; | |
219 | } | |
220 | } | |
221 | ||
222 | if (irq) { | |
223 | ret = request_irq(irq, i2c_pca_pf_handler, | |
224 | IRQF_TRIGGER_FALLING, i2c->adap.name, i2c); | |
225 | if (ret) | |
226 | goto e_reqirq; | |
227 | } | |
228 | ||
229 | if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) { | |
230 | ret = -ENODEV; | |
231 | goto e_adapt; | |
232 | } | |
233 | ||
234 | platform_set_drvdata(pdev, i2c); | |
235 | ||
236 | printk(KERN_INFO "%s registered.\n", i2c->adap.name); | |
237 | ||
238 | return 0; | |
239 | ||
240 | e_adapt: | |
241 | if (irq) | |
242 | free_irq(irq, i2c); | |
243 | e_reqirq: | |
244 | if (i2c->gpio > -1) | |
245 | gpio_free(i2c->gpio); | |
246 | ||
247 | iounmap(i2c->reg_base); | |
248 | e_remap: | |
249 | kfree(i2c); | |
250 | e_alloc: | |
c6ffddea | 251 | release_mem_region(res->start, resource_size(res)); |
244fbbb8 | 252 | e_print: |
eff9ec95 | 253 | printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret); |
244fbbb8 WS |
254 | return ret; |
255 | } | |
256 | ||
257 | static int __devexit i2c_pca_pf_remove(struct platform_device *pdev) | |
258 | { | |
259 | struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev); | |
260 | platform_set_drvdata(pdev, NULL); | |
261 | ||
262 | i2c_del_adapter(&i2c->adap); | |
263 | ||
264 | if (i2c->irq) | |
265 | free_irq(i2c->irq, i2c); | |
266 | ||
267 | if (i2c->gpio > -1) | |
268 | gpio_free(i2c->gpio); | |
269 | ||
270 | iounmap(i2c->reg_base); | |
271 | release_mem_region(i2c->io_base, i2c->io_size); | |
272 | kfree(i2c); | |
273 | ||
274 | return 0; | |
275 | } | |
276 | ||
277 | static struct platform_driver i2c_pca_pf_driver = { | |
278 | .probe = i2c_pca_pf_probe, | |
279 | .remove = __devexit_p(i2c_pca_pf_remove), | |
280 | .driver = { | |
281 | .name = "i2c-pca-platform", | |
282 | .owner = THIS_MODULE, | |
283 | }, | |
284 | }; | |
285 | ||
286 | static int __init i2c_pca_pf_init(void) | |
287 | { | |
288 | return platform_driver_register(&i2c_pca_pf_driver); | |
289 | } | |
290 | ||
291 | static void __exit i2c_pca_pf_exit(void) | |
292 | { | |
293 | platform_driver_unregister(&i2c_pca_pf_driver); | |
294 | } | |
295 | ||
296 | MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>"); | |
eff9ec95 | 297 | MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver"); |
244fbbb8 WS |
298 | MODULE_LICENSE("GPL"); |
299 | ||
300 | module_init(i2c_pca_pf_init); | |
301 | module_exit(i2c_pca_pf_exit); | |
302 |