OMAPDSS: VENC: fix NULL pointer dereference in DSS2 VENC sysfs debug attr on OMAP4
[zen-stable.git] / drivers / mfd / tc3589x.c
blobde979742c6fc1049cf49f858870034f3885eeb05
1 /*
2 * Copyright (C) ST-Ericsson SA 2010
4 * License Terms: GNU General Public License, version 2
5 * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
6 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
7 */
9 #include <linux/module.h>
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/slab.h>
13 #include <linux/i2c.h>
14 #include <linux/mfd/core.h>
15 #include <linux/mfd/tc3589x.h>
17 #define TC3589x_CLKMODE_MODCTL_SLEEP 0x0
18 #define TC3589x_CLKMODE_MODCTL_OPERATION (1 << 0)
20 /**
21 * tc3589x_reg_read() - read a single TC3589x register
22 * @tc3589x: Device to read from
23 * @reg: Register to read
25 int tc3589x_reg_read(struct tc3589x *tc3589x, u8 reg)
27 int ret;
29 ret = i2c_smbus_read_byte_data(tc3589x->i2c, reg);
30 if (ret < 0)
31 dev_err(tc3589x->dev, "failed to read reg %#x: %d\n",
32 reg, ret);
34 return ret;
36 EXPORT_SYMBOL_GPL(tc3589x_reg_read);
38 /**
39 * tc3589x_reg_read() - write a single TC3589x register
40 * @tc3589x: Device to write to
41 * @reg: Register to read
42 * @data: Value to write
44 int tc3589x_reg_write(struct tc3589x *tc3589x, u8 reg, u8 data)
46 int ret;
48 ret = i2c_smbus_write_byte_data(tc3589x->i2c, reg, data);
49 if (ret < 0)
50 dev_err(tc3589x->dev, "failed to write reg %#x: %d\n",
51 reg, ret);
53 return ret;
55 EXPORT_SYMBOL_GPL(tc3589x_reg_write);
57 /**
58 * tc3589x_block_read() - read multiple TC3589x registers
59 * @tc3589x: Device to read from
60 * @reg: First register
61 * @length: Number of registers
62 * @values: Buffer to write to
64 int tc3589x_block_read(struct tc3589x *tc3589x, u8 reg, u8 length, u8 *values)
66 int ret;
68 ret = i2c_smbus_read_i2c_block_data(tc3589x->i2c, reg, length, values);
69 if (ret < 0)
70 dev_err(tc3589x->dev, "failed to read regs %#x: %d\n",
71 reg, ret);
73 return ret;
75 EXPORT_SYMBOL_GPL(tc3589x_block_read);
77 /**
78 * tc3589x_block_write() - write multiple TC3589x registers
79 * @tc3589x: Device to write to
80 * @reg: First register
81 * @length: Number of registers
82 * @values: Values to write
84 int tc3589x_block_write(struct tc3589x *tc3589x, u8 reg, u8 length,
85 const u8 *values)
87 int ret;
89 ret = i2c_smbus_write_i2c_block_data(tc3589x->i2c, reg, length,
90 values);
91 if (ret < 0)
92 dev_err(tc3589x->dev, "failed to write regs %#x: %d\n",
93 reg, ret);
95 return ret;
97 EXPORT_SYMBOL_GPL(tc3589x_block_write);
99 /**
100 * tc3589x_set_bits() - set the value of a bitfield in a TC3589x register
101 * @tc3589x: Device to write to
102 * @reg: Register to write
103 * @mask: Mask of bits to set
104 * @values: Value to set
106 int tc3589x_set_bits(struct tc3589x *tc3589x, u8 reg, u8 mask, u8 val)
108 int ret;
110 mutex_lock(&tc3589x->lock);
112 ret = tc3589x_reg_read(tc3589x, reg);
113 if (ret < 0)
114 goto out;
116 ret &= ~mask;
117 ret |= val;
119 ret = tc3589x_reg_write(tc3589x, reg, ret);
121 out:
122 mutex_unlock(&tc3589x->lock);
123 return ret;
125 EXPORT_SYMBOL_GPL(tc3589x_set_bits);
127 static struct resource gpio_resources[] = {
129 .start = TC3589x_INT_GPIIRQ,
130 .end = TC3589x_INT_GPIIRQ,
131 .flags = IORESOURCE_IRQ,
135 static struct resource keypad_resources[] = {
137 .start = TC3589x_INT_KBDIRQ,
138 .end = TC3589x_INT_KBDIRQ,
139 .flags = IORESOURCE_IRQ,
143 static struct mfd_cell tc3589x_dev_gpio[] = {
145 .name = "tc3589x-gpio",
146 .num_resources = ARRAY_SIZE(gpio_resources),
147 .resources = &gpio_resources[0],
151 static struct mfd_cell tc3589x_dev_keypad[] = {
153 .name = "tc3589x-keypad",
154 .num_resources = ARRAY_SIZE(keypad_resources),
155 .resources = &keypad_resources[0],
159 static irqreturn_t tc3589x_irq(int irq, void *data)
161 struct tc3589x *tc3589x = data;
162 int status;
164 again:
165 status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
166 if (status < 0)
167 return IRQ_NONE;
169 while (status) {
170 int bit = __ffs(status);
172 handle_nested_irq(tc3589x->irq_base + bit);
173 status &= ~(1 << bit);
177 * A dummy read or write (to any register) appears to be necessary to
178 * have the last interrupt clear (for example, GPIO IC write) take
179 * effect. In such a case, recheck for any interrupt which is still
180 * pending.
182 status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
183 if (status)
184 goto again;
186 return IRQ_HANDLED;
189 static int tc3589x_irq_init(struct tc3589x *tc3589x)
191 int base = tc3589x->irq_base;
192 int irq;
194 for (irq = base; irq < base + TC3589x_NR_INTERNAL_IRQS; irq++) {
195 irq_set_chip_data(irq, tc3589x);
196 irq_set_chip_and_handler(irq, &dummy_irq_chip,
197 handle_edge_irq);
198 irq_set_nested_thread(irq, 1);
199 #ifdef CONFIG_ARM
200 set_irq_flags(irq, IRQF_VALID);
201 #else
202 irq_set_noprobe(irq);
203 #endif
206 return 0;
209 static void tc3589x_irq_remove(struct tc3589x *tc3589x)
211 int base = tc3589x->irq_base;
212 int irq;
214 for (irq = base; irq < base + TC3589x_NR_INTERNAL_IRQS; irq++) {
215 #ifdef CONFIG_ARM
216 set_irq_flags(irq, 0);
217 #endif
218 irq_set_chip_and_handler(irq, NULL, NULL);
219 irq_set_chip_data(irq, NULL);
223 static int tc3589x_chip_init(struct tc3589x *tc3589x)
225 int manf, ver, ret;
227 manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);
228 if (manf < 0)
229 return manf;
231 ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);
232 if (ver < 0)
233 return ver;
235 if (manf != TC3589x_MANFCODE_MAGIC) {
236 dev_err(tc3589x->dev, "unknown manufacturer: %#x\n", manf);
237 return -EINVAL;
240 dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
243 * Put everything except the IRQ module into reset;
244 * also spare the GPIO module for any pin initialization
245 * done during pre-kernel boot
247 ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
248 TC3589x_RSTCTRL_TIMRST
249 | TC3589x_RSTCTRL_ROTRST
250 | TC3589x_RSTCTRL_KBDRST);
251 if (ret < 0)
252 return ret;
254 /* Clear the reset interrupt. */
255 return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);
258 static int __devinit tc3589x_device_init(struct tc3589x *tc3589x)
260 int ret = 0;
261 unsigned int blocks = tc3589x->pdata->block;
263 if (blocks & TC3589x_BLOCK_GPIO) {
264 ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,
265 ARRAY_SIZE(tc3589x_dev_gpio), NULL,
266 tc3589x->irq_base);
267 if (ret) {
268 dev_err(tc3589x->dev, "failed to add gpio child\n");
269 return ret;
271 dev_info(tc3589x->dev, "added gpio block\n");
274 if (blocks & TC3589x_BLOCK_KEYPAD) {
275 ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,
276 ARRAY_SIZE(tc3589x_dev_keypad), NULL,
277 tc3589x->irq_base);
278 if (ret) {
279 dev_err(tc3589x->dev, "failed to keypad child\n");
280 return ret;
282 dev_info(tc3589x->dev, "added keypad block\n");
285 return ret;
288 static int __devinit tc3589x_probe(struct i2c_client *i2c,
289 const struct i2c_device_id *id)
291 struct tc3589x_platform_data *pdata = i2c->dev.platform_data;
292 struct tc3589x *tc3589x;
293 int ret;
295 if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
296 | I2C_FUNC_SMBUS_I2C_BLOCK))
297 return -EIO;
299 tc3589x = kzalloc(sizeof(struct tc3589x), GFP_KERNEL);
300 if (!tc3589x)
301 return -ENOMEM;
303 mutex_init(&tc3589x->lock);
305 tc3589x->dev = &i2c->dev;
306 tc3589x->i2c = i2c;
307 tc3589x->pdata = pdata;
308 tc3589x->irq_base = pdata->irq_base;
309 tc3589x->num_gpio = id->driver_data;
311 i2c_set_clientdata(i2c, tc3589x);
313 ret = tc3589x_chip_init(tc3589x);
314 if (ret)
315 goto out_free;
317 ret = tc3589x_irq_init(tc3589x);
318 if (ret)
319 goto out_free;
321 ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,
322 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
323 "tc3589x", tc3589x);
324 if (ret) {
325 dev_err(tc3589x->dev, "failed to request IRQ: %d\n", ret);
326 goto out_removeirq;
329 ret = tc3589x_device_init(tc3589x);
330 if (ret) {
331 dev_err(tc3589x->dev, "failed to add child devices\n");
332 goto out_freeirq;
335 return 0;
337 out_freeirq:
338 free_irq(tc3589x->i2c->irq, tc3589x);
339 out_removeirq:
340 tc3589x_irq_remove(tc3589x);
341 out_free:
342 kfree(tc3589x);
343 return ret;
346 static int __devexit tc3589x_remove(struct i2c_client *client)
348 struct tc3589x *tc3589x = i2c_get_clientdata(client);
350 mfd_remove_devices(tc3589x->dev);
352 free_irq(tc3589x->i2c->irq, tc3589x);
353 tc3589x_irq_remove(tc3589x);
355 kfree(tc3589x);
357 return 0;
360 #ifdef CONFIG_PM
361 static int tc3589x_suspend(struct device *dev)
363 struct tc3589x *tc3589x = dev_get_drvdata(dev);
364 struct i2c_client *client = tc3589x->i2c;
365 int ret = 0;
367 /* put the system to sleep mode */
368 if (!device_may_wakeup(&client->dev))
369 ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
370 TC3589x_CLKMODE_MODCTL_SLEEP);
372 return ret;
375 static int tc3589x_resume(struct device *dev)
377 struct tc3589x *tc3589x = dev_get_drvdata(dev);
378 struct i2c_client *client = tc3589x->i2c;
379 int ret = 0;
381 /* enable the system into operation */
382 if (!device_may_wakeup(&client->dev))
383 ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
384 TC3589x_CLKMODE_MODCTL_OPERATION);
386 return ret;
389 static const SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops, tc3589x_suspend,
390 tc3589x_resume);
391 #endif
393 static const struct i2c_device_id tc3589x_id[] = {
394 { "tc3589x", 24 },
397 MODULE_DEVICE_TABLE(i2c, tc3589x_id);
399 static struct i2c_driver tc3589x_driver = {
400 .driver.name = "tc3589x",
401 .driver.owner = THIS_MODULE,
402 #ifdef CONFIG_PM
403 .driver.pm = &tc3589x_dev_pm_ops,
404 #endif
405 .probe = tc3589x_probe,
406 .remove = __devexit_p(tc3589x_remove),
407 .id_table = tc3589x_id,
410 static int __init tc3589x_init(void)
412 return i2c_add_driver(&tc3589x_driver);
414 subsys_initcall(tc3589x_init);
416 static void __exit tc3589x_exit(void)
418 i2c_del_driver(&tc3589x_driver);
420 module_exit(tc3589x_exit);
422 MODULE_LICENSE("GPL v2");
423 MODULE_DESCRIPTION("TC3589x MFD core driver");
424 MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");