ixp4xx: fix lzma/jffs2 config options
[openwrt.git] / target / linux / ixp4xx / patches-2.6.33 / 020-gateworks_i2c_pld.patch
1 --- /dev/null
2 +++ b/drivers/gpio/gw_i2c_pld.c
3 @@ -0,0 +1,371 @@
4 +/*
5 + * Gateworks I2C PLD GPIO expander
6 + *
7 + * Copyright (C) 2009 Gateworks Corporation
8 + *
9 + * This program is free software; you can redistribute it and/or modify
10 + * it under the terms of the GNU General Public License as published by
11 + * the Free Software Foundation; either version 2 of the License, or
12 + * (at your option) any later version.
13 + *
14 + * This program is distributed in the hope that it will be useful,
15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 + * GNU General Public License for more details.
18 + *
19 + * You should have received a copy of the GNU General Public License
20 + * along with this program; if not, write to the Free Software
21 + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 + */
23 +
24 +#include <linux/kernel.h>
25 +#include <linux/slab.h>
26 +#include <linux/hardirq.h>
27 +#include <linux/i2c.h>
28 +#include <linux/i2c/gw_i2c_pld.h>
29 +#include <asm/gpio.h>
30 +
31 +static const struct i2c_device_id gw_i2c_pld_id[] = {
32 + { "gw_i2c_pld", 8 },
33 + { }
34 +};
35 +MODULE_DEVICE_TABLE(i2c, gw_i2c_pld_id);
36 +
37 +/*
38 + * The Gateworks I2C PLD chip only expose one read and one
39 + * write register. Writing a "one" bit (to match the reset state) lets
40 + * that pin be used as an input. It is an open-drain model.
41 + */
42 +
43 +struct gw_i2c_pld {
44 + struct gpio_chip chip;
45 + struct i2c_client *client;
46 + unsigned out; /* software latch */
47 +};
48 +
49 +/*-------------------------------------------------------------------------*/
50 +
51 +/*
52 + * The Gateworks I2C PLD chip does not properly send the acknowledge bit
53 + * thus we cannot use standard i2c_smbus functions. We have recreated
54 + * our own here, but we still use the mutex_lock to lock the i2c_bus
55 + * as the device still exists on the I2C bus.
56 +*/
57 +
58 +#define PLD_SCL_GPIO 6
59 +#define PLD_SDA_GPIO 7
60 +
61 +#define SCL_LO() gpio_line_set(PLD_SCL_GPIO, IXP4XX_GPIO_LOW)
62 +#define SCL_HI() gpio_line_set(PLD_SCL_GPIO, IXP4XX_GPIO_HIGH)
63 +#define SCL_EN() gpio_line_config(PLD_SCL_GPIO, IXP4XX_GPIO_OUT)
64 +#define SDA_LO() gpio_line_set(PLD_SDA_GPIO, IXP4XX_GPIO_LOW)
65 +#define SDA_HI() gpio_line_set(PLD_SDA_GPIO, IXP4XX_GPIO_HIGH)
66 +#define SDA_EN() gpio_line_config(PLD_SDA_GPIO, IXP4XX_GPIO_OUT)
67 +#define SDA_DIS() gpio_line_config(PLD_SDA_GPIO, IXP4XX_GPIO_IN)
68 +#define SDA_IN(x) gpio_line_get(PLD_SDA_GPIO, &x);
69 +
70 +static int i2c_pld_write_byte(int address, int byte)
71 +{
72 + int i;
73 +
74 + address = (address << 1) & ~0x1;
75 +
76 + SDA_HI();
77 + SDA_EN();
78 + SCL_EN();
79 + SCL_HI();
80 + SDA_LO();
81 + SCL_LO();
82 +
83 + for (i = 7; i >= 0; i--)
84 + {
85 + if (address & (1 << i))
86 + SDA_HI();
87 + else
88 + SDA_LO();
89 +
90 + SCL_HI();
91 + SCL_LO();
92 + }
93 +
94 + SDA_DIS();
95 + SCL_HI();
96 + SDA_IN(i);
97 + SCL_LO();
98 + SDA_EN();
99 +
100 + for (i = 7; i >= 0; i--)
101 + {
102 + if (byte & (1 << i))
103 + SDA_HI();
104 + else
105 + SDA_LO();
106 + SCL_HI();
107 + SCL_LO();
108 + }
109 +
110 + SDA_DIS();
111 + SCL_HI();
112 + SDA_IN(i);
113 + SCL_LO();
114 +
115 + SDA_HI();
116 + SDA_EN();
117 +
118 + SDA_LO();
119 + SCL_HI();
120 + SDA_HI();
121 + SCL_LO();
122 + SCL_HI();
123 +
124 + return 0;
125 +}
126 +
127 +static unsigned int i2c_pld_read_byte(int address)
128 +{
129 + int i = 0, byte = 0;
130 + int bit;
131 +
132 + address = (address << 1) | 0x1;
133 +
134 + SDA_HI();
135 + SDA_EN();
136 + SCL_EN();
137 + SCL_HI();
138 + SDA_LO();
139 + SCL_LO();
140 +
141 + for (i = 7; i >= 0; i--)
142 + {
143 + if (address & (1 << i))
144 + SDA_HI();
145 + else
146 + SDA_LO();
147 +
148 + SCL_HI();
149 + SCL_LO();
150 + }
151 +
152 + SDA_DIS();
153 + SCL_HI();
154 + SDA_IN(i);
155 + SCL_LO();
156 + SDA_EN();
157 +
158 + SDA_DIS();
159 + for (i = 7; i >= 0; i--)
160 + {
161 + SCL_HI();
162 + SDA_IN(bit);
163 + byte |= bit << i;
164 + SCL_LO();
165 + }
166 +
167 + SDA_LO();
168 + SCL_HI();
169 + SDA_HI();
170 + SCL_LO();
171 + SCL_HI();
172 +
173 + return byte;
174 +}
175 +
176 +
177 +static int gw_i2c_pld_input8(struct gpio_chip *chip, unsigned offset)
178 +{
179 + int ret;
180 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
181 + struct i2c_adapter *adap = gpio->client->adapter;
182 +
183 + if (in_atomic() || irqs_disabled()) {
184 + ret = mutex_trylock(&adap->bus_lock);
185 + if (!ret)
186 + /* I2C activity is ongoing. */
187 + return -EAGAIN;
188 + } else {
189 + mutex_lock_nested(&adap->bus_lock, adap->level);
190 + }
191 +
192 + gpio->out |= (1 << offset);
193 +
194 + ret = i2c_pld_write_byte(gpio->client->addr, gpio->out);
195 +
196 + mutex_unlock(&adap->bus_lock);
197 +
198 + return ret;
199 +}
200 +
201 +static int gw_i2c_pld_get8(struct gpio_chip *chip, unsigned offset)
202 +{
203 + int ret;
204 + s32 value;
205 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
206 + struct i2c_adapter *adap = gpio->client->adapter;
207 +
208 + if (in_atomic() || irqs_disabled()) {
209 + ret = mutex_trylock(&adap->bus_lock);
210 + if (!ret)
211 + /* I2C activity is ongoing. */
212 + return -EAGAIN;
213 + } else {
214 + mutex_lock_nested(&adap->bus_lock, adap->level);
215 + }
216 +
217 + value = i2c_pld_read_byte(gpio->client->addr);
218 +
219 + mutex_unlock(&adap->bus_lock);
220 +
221 + return (value < 0) ? 0 : (value & (1 << offset));
222 +}
223 +
224 +static int gw_i2c_pld_output8(struct gpio_chip *chip, unsigned offset, int value)
225 +{
226 + int ret;
227 +
228 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
229 + struct i2c_adapter *adap = gpio->client->adapter;
230 +
231 + unsigned bit = 1 << offset;
232 +
233 + if (in_atomic() || irqs_disabled()) {
234 + ret = mutex_trylock(&adap->bus_lock);
235 + if (!ret)
236 + /* I2C activity is ongoing. */
237 + return -EAGAIN;
238 + } else {
239 + mutex_lock_nested(&adap->bus_lock, adap->level);
240 + }
241 +
242 +
243 + if (value)
244 + gpio->out |= bit;
245 + else
246 + gpio->out &= ~bit;
247 +
248 + ret = i2c_pld_write_byte(gpio->client->addr, gpio->out);
249 +
250 + mutex_unlock(&adap->bus_lock);
251 +
252 + return ret;
253 +}
254 +
255 +static void gw_i2c_pld_set8(struct gpio_chip *chip, unsigned offset, int value)
256 +{
257 + gw_i2c_pld_output8(chip, offset, value);
258 +}
259 +
260 +/*-------------------------------------------------------------------------*/
261 +
262 +static int gw_i2c_pld_probe(struct i2c_client *client,
263 + const struct i2c_device_id *id)
264 +{
265 + struct gw_i2c_pld_platform_data *pdata;
266 + struct gw_i2c_pld *gpio;
267 + int status;
268 +
269 + pdata = client->dev.platform_data;
270 + if (!pdata)
271 + return -ENODEV;
272 +
273 + /* Allocate, initialize, and register this gpio_chip. */
274 + gpio = kzalloc(sizeof *gpio, GFP_KERNEL);
275 + if (!gpio)
276 + return -ENOMEM;
277 +
278 + gpio->chip.base = pdata->gpio_base;
279 + gpio->chip.can_sleep = 1;
280 + gpio->chip.dev = &client->dev;
281 + gpio->chip.owner = THIS_MODULE;
282 +
283 + gpio->chip.ngpio = pdata->nr_gpio;
284 + gpio->chip.direction_input = gw_i2c_pld_input8;
285 + gpio->chip.get = gw_i2c_pld_get8;
286 + gpio->chip.direction_output = gw_i2c_pld_output8;
287 + gpio->chip.set = gw_i2c_pld_set8;
288 +
289 + gpio->chip.label = client->name;
290 +
291 + gpio->client = client;
292 + i2c_set_clientdata(client, gpio);
293 +
294 + gpio->out = 0xFF;
295 +
296 + status = gpiochip_add(&gpio->chip);
297 + if (status < 0)
298 + goto fail;
299 +
300 + dev_info(&client->dev, "gpios %d..%d on a %s%s\n",
301 + gpio->chip.base,
302 + gpio->chip.base + gpio->chip.ngpio - 1,
303 + client->name,
304 + client->irq ? " (irq ignored)" : "");
305 +
306 + /* Let platform code set up the GPIOs and their users.
307 + * Now is the first time anyone could use them.
308 + */
309 + if (pdata->setup) {
310 + status = pdata->setup(client,
311 + gpio->chip.base, gpio->chip.ngpio,
312 + pdata->context);
313 + if (status < 0)
314 + dev_warn(&client->dev, "setup --> %d\n", status);
315 + }
316 +
317 + return 0;
318 +
319 +fail:
320 + dev_dbg(&client->dev, "probe error %d for '%s'\n",
321 + status, client->name);
322 + kfree(gpio);
323 + return status;
324 +}
325 +
326 +static int gw_i2c_pld_remove(struct i2c_client *client)
327 +{
328 + struct gw_i2c_pld_platform_data *pdata = client->dev.platform_data;
329 + struct gw_i2c_pld *gpio = i2c_get_clientdata(client);
330 + int status = 0;
331 +
332 + if (pdata->teardown) {
333 + status = pdata->teardown(client,
334 + gpio->chip.base, gpio->chip.ngpio,
335 + pdata->context);
336 + if (status < 0) {
337 + dev_err(&client->dev, "%s --> %d\n",
338 + "teardown", status);
339 + return status;
340 + }
341 + }
342 +
343 + status = gpiochip_remove(&gpio->chip);
344 + if (status == 0)
345 + kfree(gpio);
346 + else
347 + dev_err(&client->dev, "%s --> %d\n", "remove", status);
348 + return status;
349 +}
350 +
351 +static struct i2c_driver gw_i2c_pld_driver = {
352 + .driver = {
353 + .name = "gw_i2c_pld",
354 + .owner = THIS_MODULE,
355 + },
356 + .probe = gw_i2c_pld_probe,
357 + .remove = gw_i2c_pld_remove,
358 + .id_table = gw_i2c_pld_id,
359 +};
360 +
361 +static int __init gw_i2c_pld_init(void)
362 +{
363 + return i2c_add_driver(&gw_i2c_pld_driver);
364 +}
365 +module_init(gw_i2c_pld_init);
366 +
367 +static void __exit gw_i2c_pld_exit(void)
368 +{
369 + i2c_del_driver(&gw_i2c_pld_driver);
370 +}
371 +module_exit(gw_i2c_pld_exit);
372 +
373 +MODULE_LICENSE("GPL");
374 +MODULE_AUTHOR("Chris Lang");
375 --- a/drivers/gpio/Kconfig
376 +++ b/drivers/gpio/Kconfig
377 @@ -221,6 +221,14 @@ config GPIO_TIMBERDALE
378 ---help---
379 Add support for the GPIO IP in the timberdale FPGA.
380
381 +config GPIO_GW_I2C_PLD
382 + tristate "Gateworks I2C PLD GPIO Expander"
383 + depends on I2C
384 + help
385 + Say yes here to provide access to the Gateworks I2C PLD GPIO
386 + Expander. This is used at least on the GW2358-4.
387 +
388 +
389 comment "SPI GPIO expanders:"
390
391 config GPIO_MAX7301
392 --- a/drivers/gpio/Makefile
393 +++ b/drivers/gpio/Makefile
394 @@ -22,3 +22,4 @@ obj-$(CONFIG_GPIO_CS5535) += cs5535-gpio
395 obj-$(CONFIG_GPIO_BT8XX) += bt8xxgpio.o
396 obj-$(CONFIG_GPIO_VR41XX) += vr41xx_giu.o
397 obj-$(CONFIG_GPIO_WM831X) += wm831x-gpio.o
398 +obj-$(CONFIG_GPIO_GW_I2C_PLD) += gw_i2c_pld.o
399 --- /dev/null
400 +++ b/include/linux/i2c/gw_i2c_pld.h
401 @@ -0,0 +1,20 @@
402 +#ifndef __LINUX_GW_I2C_PLD_H
403 +#define __LINUX_GW_I2C_PLD_H
404 +
405 +/**
406 + * The Gateworks I2C PLD Implements an additional 8 bits of GPIO through the PLD
407 + */
408 +
409 +struct gw_i2c_pld_platform_data {
410 + unsigned gpio_base;
411 + unsigned nr_gpio;
412 + int (*setup)(struct i2c_client *client,
413 + int gpio, unsigned ngpio,
414 + void *context);
415 + int (*teardown)(struct i2c_client *client,
416 + int gpio, unsigned ngpio,
417 + void *context);
418 + void *context;
419 +};
420 +
421 +#endif /* __LINUX_GW_I2C_PLD_H */
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