ixp4xx: add v3.18 support
[openwrt/svn-archive/archive.git] / target / linux / ixp4xx / patches-3.18 / 020-gateworks_i2c_pld.patch
1 Index: linux-3.18.5/drivers/gpio/Kconfig
2 ===================================================================
3 --- linux-3.18.5.orig/drivers/gpio/Kconfig 2015-01-30 02:41:03.000000000 +0100
4 +++ linux-3.18.5/drivers/gpio/Kconfig 2015-02-09 13:55:16.942041668 +0100
5 @@ -794,6 +794,14 @@
6 Support for the RDC R321x SoC GPIOs over southbridge
7 PCI configuration space.
8
9 +config GPIO_GW_I2C_PLD
10 + tristate "Gateworks I2C PLD GPIO Expander"
11 + depends on I2C
12 + help
13 + Say yes here to provide access to the Gateworks I2C PLD GPIO
14 + Expander. This is used at least on the GW2358-4.
15 +
16 +
17 comment "SPI GPIO expanders:"
18
19 config GPIO_MAX7301
20 Index: linux-3.18.5/drivers/gpio/Makefile
21 ===================================================================
22 --- linux-3.18.5.orig/drivers/gpio/Makefile 2015-01-30 02:41:03.000000000 +0100
23 +++ linux-3.18.5/drivers/gpio/Makefile 2015-02-09 13:56:05.990145732 +0100
24 @@ -106,3 +106,4 @@
25 obj-$(CONFIG_GPIO_XTENSA) += gpio-xtensa.o
26 obj-$(CONFIG_GPIO_ZEVIO) += gpio-zevio.o
27 obj-$(CONFIG_GPIO_ZYNQ) += gpio-zynq.o
28 +obj-$(CONFIG_GPIO_GW_I2C_PLD) += gw_i2c_pld.o
29 Index: linux-3.18.5/drivers/gpio/gw_i2c_pld.c
30 ===================================================================
31 --- /dev/null 1970-01-01 00:00:00.000000000 +0000
32 +++ linux-3.18.5/drivers/gpio/gw_i2c_pld.c 2015-02-09 14:02:00.146895858 +0100
33 @@ -0,0 +1,371 @@
34 +/*
35 + * Gateworks I2C PLD GPIO expander
36 + *
37 + * Copyright (C) 2009 Gateworks Corporation
38 + *
39 + * This program is free software; you can redistribute it and/or modify
40 + * it under the terms of the GNU General Public License as published by
41 + * the Free Software Foundation; either version 2 of the License, or
42 + * (at your option) any later version.
43 + *
44 + * This program is distributed in the hope that it will be useful,
45 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
46 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
47 + * GNU General Public License for more details.
48 + *
49 + * You should have received a copy of the GNU General Public License
50 + * along with this program; if not, write to the Free Software
51 + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
52 + */
53 +
54 +#include <linux/kernel.h>
55 +#include <linux/slab.h>
56 +#include <linux/hardirq.h>
57 +#include <linux/i2c.h>
58 +#include <linux/i2c/gw_i2c_pld.h>
59 +#include <linux/module.h>
60 +#include <linux/export.h>
61 +#include <asm/gpio.h>
62 +#include <mach/hardware.h>
63 +
64 +static const struct i2c_device_id gw_i2c_pld_id[] = {
65 + { "gw_i2c_pld", 8 },
66 + { }
67 +};
68 +MODULE_DEVICE_TABLE(i2c, gw_i2c_pld_id);
69 +
70 +/*
71 + * The Gateworks I2C PLD chip only expose one read and one
72 + * write register. Writing a "one" bit (to match the reset state) lets
73 + * that pin be used as an input. It is an open-drain model.
74 + */
75 +
76 +struct gw_i2c_pld {
77 + struct gpio_chip chip;
78 + struct i2c_client *client;
79 + unsigned out; /* software latch */
80 +};
81 +
82 +/*-------------------------------------------------------------------------*/
83 +
84 +/*
85 + * The Gateworks I2C PLD chip does not properly send the acknowledge bit
86 + * thus we cannot use standard i2c_smbus functions. We have recreated
87 + * our own here, but we still use the rt_mutex_lock to lock the i2c_bus
88 + * as the device still exists on the I2C bus.
89 +*/
90 +
91 +#define PLD_SCL_GPIO 6
92 +#define PLD_SDA_GPIO 7
93 +
94 +#define SCL_LO() gpio_line_set(PLD_SCL_GPIO, IXP4XX_GPIO_LOW)
95 +#define SCL_HI() gpio_line_set(PLD_SCL_GPIO, IXP4XX_GPIO_HIGH)
96 +#define SCL_EN() gpio_line_config(PLD_SCL_GPIO, IXP4XX_GPIO_OUT)
97 +#define SDA_LO() gpio_line_set(PLD_SDA_GPIO, IXP4XX_GPIO_LOW)
98 +#define SDA_HI() gpio_line_set(PLD_SDA_GPIO, IXP4XX_GPIO_HIGH)
99 +#define SDA_EN() gpio_line_config(PLD_SDA_GPIO, IXP4XX_GPIO_OUT)
100 +#define SDA_DIS() gpio_line_config(PLD_SDA_GPIO, IXP4XX_GPIO_IN)
101 +#define SDA_IN(x) gpio_line_get(PLD_SDA_GPIO, &x);
102 +
103 +static int i2c_pld_write_byte(int address, int byte)
104 +{
105 + int i;
106 +
107 + address = (address << 1) & ~0x1;
108 +
109 + SDA_HI();
110 + SDA_EN();
111 + SCL_EN();
112 + SCL_HI();
113 + SDA_LO();
114 + SCL_LO();
115 +
116 + for (i = 7; i >= 0; i--)
117 + {
118 + if (address & (1 << i))
119 + SDA_HI();
120 + else
121 + SDA_LO();
122 +
123 + SCL_HI();
124 + SCL_LO();
125 + }
126 +
127 + SDA_DIS();
128 + SCL_HI();
129 + SDA_IN(i);
130 + SCL_LO();
131 + SDA_EN();
132 +
133 + for (i = 7; i >= 0; i--)
134 + {
135 + if (byte & (1 << i))
136 + SDA_HI();
137 + else
138 + SDA_LO();
139 + SCL_HI();
140 + SCL_LO();
141 + }
142 +
143 + SDA_DIS();
144 + SCL_HI();
145 + SDA_IN(i);
146 + SCL_LO();
147 +
148 + SDA_HI();
149 + SDA_EN();
150 +
151 + SDA_LO();
152 + SCL_HI();
153 + SDA_HI();
154 + SCL_LO();
155 + SCL_HI();
156 +
157 + return 0;
158 +}
159 +
160 +static unsigned int i2c_pld_read_byte(int address)
161 +{
162 + int i = 0, byte = 0;
163 + int bit;
164 +
165 + address = (address << 1) | 0x1;
166 +
167 + SDA_HI();
168 + SDA_EN();
169 + SCL_EN();
170 + SCL_HI();
171 + SDA_LO();
172 + SCL_LO();
173 +
174 + for (i = 7; i >= 0; i--)
175 + {
176 + if (address & (1 << i))
177 + SDA_HI();
178 + else
179 + SDA_LO();
180 +
181 + SCL_HI();
182 + SCL_LO();
183 + }
184 +
185 + SDA_DIS();
186 + SCL_HI();
187 + SDA_IN(i);
188 + SCL_LO();
189 + SDA_EN();
190 +
191 + SDA_DIS();
192 + for (i = 7; i >= 0; i--)
193 + {
194 + SCL_HI();
195 + SDA_IN(bit);
196 + byte |= bit << i;
197 + SCL_LO();
198 + }
199 +
200 + SDA_LO();
201 + SCL_HI();
202 + SDA_HI();
203 + SCL_LO();
204 + SCL_HI();
205 +
206 + return byte;
207 +}
208 +
209 +
210 +static int gw_i2c_pld_input8(struct gpio_chip *chip, unsigned offset)
211 +{
212 + int ret;
213 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
214 + struct i2c_adapter *adap = gpio->client->adapter;
215 +
216 + if (in_atomic() || irqs_disabled()) {
217 + ret = rt_mutex_trylock(&adap->bus_lock);
218 + if (!ret)
219 + /* I2C activity is ongoing. */
220 + return -EAGAIN;
221 + } else {
222 + rt_mutex_lock(&adap->bus_lock);
223 + }
224 +
225 + gpio->out |= (1 << offset);
226 +
227 + ret = i2c_pld_write_byte(gpio->client->addr, gpio->out);
228 +
229 + rt_mutex_unlock(&adap->bus_lock);
230 +
231 + return ret;
232 +}
233 +
234 +static int gw_i2c_pld_get8(struct gpio_chip *chip, unsigned offset)
235 +{
236 + int ret;
237 + s32 value;
238 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
239 + struct i2c_adapter *adap = gpio->client->adapter;
240 +
241 + if (in_atomic() || irqs_disabled()) {
242 + ret = rt_mutex_trylock(&adap->bus_lock);
243 + if (!ret)
244 + /* I2C activity is ongoing. */
245 + return -EAGAIN;
246 + } else {
247 + rt_mutex_lock(&adap->bus_lock);
248 + }
249 +
250 + value = i2c_pld_read_byte(gpio->client->addr);
251 +
252 + rt_mutex_unlock(&adap->bus_lock);
253 +
254 + return (value < 0) ? 0 : (value & (1 << offset));
255 +}
256 +
257 +static int gw_i2c_pld_output8(struct gpio_chip *chip, unsigned offset, int value)
258 +{
259 + int ret;
260 +
261 + struct gw_i2c_pld *gpio = container_of(chip, struct gw_i2c_pld, chip);
262 + struct i2c_adapter *adap = gpio->client->adapter;
263 +
264 + unsigned bit = 1 << offset;
265 +
266 + if (in_atomic() || irqs_disabled()) {
267 + ret = rt_mutex_trylock(&adap->bus_lock);
268 + if (!ret)
269 + /* I2C activity is ongoing. */
270 + return -EAGAIN;
271 + } else {
272 + rt_mutex_lock(&adap->bus_lock);
273 + }
274 +
275 +
276 + if (value)
277 + gpio->out |= bit;
278 + else
279 + gpio->out &= ~bit;
280 +
281 + ret = i2c_pld_write_byte(gpio->client->addr, gpio->out);
282 +
283 + rt_mutex_unlock(&adap->bus_lock);
284 +
285 + return ret;
286 +}
287 +
288 +static void gw_i2c_pld_set8(struct gpio_chip *chip, unsigned offset, int value)
289 +{
290 + gw_i2c_pld_output8(chip, offset, value);
291 +}
292 +
293 +/*-------------------------------------------------------------------------*/
294 +
295 +static int gw_i2c_pld_probe(struct i2c_client *client,
296 + const struct i2c_device_id *id)
297 +{
298 + struct gw_i2c_pld_platform_data *pdata;
299 + struct gw_i2c_pld *gpio;
300 + int status;
301 +
302 + pdata = client->dev.platform_data;
303 + if (!pdata)
304 + return -ENODEV;
305 +
306 + /* Allocate, initialize, and register this gpio_chip. */
307 + gpio = kzalloc(sizeof *gpio, GFP_KERNEL);
308 + if (!gpio)
309 + return -ENOMEM;
310 +
311 + gpio->chip.base = pdata->gpio_base;
312 + gpio->chip.can_sleep = 1;
313 + gpio->chip.dev = &client->dev;
314 + gpio->chip.owner = THIS_MODULE;
315 +
316 + gpio->chip.ngpio = pdata->nr_gpio;
317 + gpio->chip.direction_input = gw_i2c_pld_input8;
318 + gpio->chip.get = gw_i2c_pld_get8;
319 + gpio->chip.direction_output = gw_i2c_pld_output8;
320 + gpio->chip.set = gw_i2c_pld_set8;
321 +
322 + gpio->chip.label = client->name;
323 +
324 + gpio->client = client;
325 + i2c_set_clientdata(client, gpio);
326 +
327 + gpio->out = 0xFF;
328 +
329 + status = gpiochip_add(&gpio->chip);
330 + if (status < 0)
331 + goto fail;
332 +
333 + dev_info(&client->dev, "gpios %d..%d on a %s%s\n",
334 + gpio->chip.base,
335 + gpio->chip.base + gpio->chip.ngpio - 1,
336 + client->name,
337 + client->irq ? " (irq ignored)" : "");
338 +
339 + /* Let platform code set up the GPIOs and their users.
340 + * Now is the first time anyone could use them.
341 + */
342 + if (pdata->setup) {
343 + status = pdata->setup(client,
344 + gpio->chip.base, gpio->chip.ngpio,
345 + pdata->context);
346 + if (status < 0)
347 + dev_warn(&client->dev, "setup --> %d\n", status);
348 + }
349 +
350 + return 0;
351 +
352 +fail:
353 + dev_dbg(&client->dev, "probe error %d for '%s'\n",
354 + status, client->name);
355 + kfree(gpio);
356 + return status;
357 +}
358 +
359 +static int gw_i2c_pld_remove(struct i2c_client *client)
360 +{
361 + struct gw_i2c_pld_platform_data *pdata = client->dev.platform_data;
362 + struct gw_i2c_pld *gpio = i2c_get_clientdata(client);
363 + int status = 0;
364 +
365 + if (pdata->teardown) {
366 + status = pdata->teardown(client,
367 + gpio->chip.base, gpio->chip.ngpio,
368 + pdata->context);
369 + if (status < 0) {
370 + dev_err(&client->dev, "%s --> %d\n",
371 + "teardown", status);
372 + return status;
373 + }
374 + }
375 +
376 + gpiochip_remove(&gpio->chip);
377 + kfree(gpio);
378 + return 0;
379 +}
380 +
381 +static struct i2c_driver gw_i2c_pld_driver = {
382 + .driver = {
383 + .name = "gw_i2c_pld",
384 + .owner = THIS_MODULE,
385 + },
386 + .probe = gw_i2c_pld_probe,
387 + .remove = gw_i2c_pld_remove,
388 + .id_table = gw_i2c_pld_id,
389 +};
390 +
391 +static int __init gw_i2c_pld_init(void)
392 +{
393 + return i2c_add_driver(&gw_i2c_pld_driver);
394 +}
395 +module_init(gw_i2c_pld_init);
396 +
397 +static void __exit gw_i2c_pld_exit(void)
398 +{
399 + i2c_del_driver(&gw_i2c_pld_driver);
400 +}
401 +module_exit(gw_i2c_pld_exit);
402 +
403 +MODULE_LICENSE("GPL");
404 +MODULE_AUTHOR("Chris Lang");
405 Index: linux-3.18.5/include/linux/i2c/gw_i2c_pld.h
406 ===================================================================
407 --- /dev/null 1970-01-01 00:00:00.000000000 +0000
408 +++ linux-3.18.5/include/linux/i2c/gw_i2c_pld.h 2015-02-09 13:55:16.946041675 +0100
409 @@ -0,0 +1,20 @@
410 +#ifndef __LINUX_GW_I2C_PLD_H
411 +#define __LINUX_GW_I2C_PLD_H
412 +
413 +/**
414 + * The Gateworks I2C PLD Implements an additional 8 bits of GPIO through the PLD
415 + */
416 +
417 +struct gw_i2c_pld_platform_data {
418 + unsigned gpio_base;
419 + unsigned nr_gpio;
420 + int (*setup)(struct i2c_client *client,
421 + int gpio, unsigned ngpio,
422 + void *context);
423 + int (*teardown)(struct i2c_client *client,
424 + int gpio, unsigned ngpio,
425 + void *context);
426 + void *context;
427 +};
428 +
429 +#endif /* __LINUX_GW_I2C_PLD_H */