tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * max3107.c - spi uart protocol driver for Maxim 3107
3 * Based on max3100.c
4 * by Christian Pellegrin <chripell@evolware.org>
5 * and max3110.c
6 * by Feng Tang <feng.tang@intel.com>
7 *
8 * Copyright (C) Aavamobile 2009
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 *
28 */
29
30#include <linux/delay.h>
31#include <linux/device.h>
32#include <linux/serial_core.h>
33#include <linux/serial.h>
34#include <linux/spi/spi.h>
35#include <linux/freezer.h>
36#include <linux/platform_device.h>
37#include <linux/gpio.h>
38#include <linux/sfi.h>
39#include <asm/mrst.h>
40#include "max3107.h"
41
42/* GPIO direction to input function */
43static int max3107_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
44{
45 struct max3107_port *s = container_of(chip, struct max3107_port, chip);
46 u16 buf[1]; /* Buffer for SPI transfer */
47
48 if (offset >= MAX3107_GPIO_COUNT) {
49 dev_err(&s->spi->dev, "Invalid GPIO\n");
50 return -EINVAL;
51 }
52
53 /* Read current GPIO configuration register */
54 buf[0] = MAX3107_GPIOCFG_REG;
55 /* Perform SPI transfer */
56 if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
57 dev_err(&s->spi->dev, "SPI transfer GPIO read failed\n");
58 return -EIO;
59 }
60 buf[0] &= MAX3107_SPI_RX_DATA_MASK;
61
62 /* Set GPIO to input */
63 buf[0] &= ~(0x0001 << offset);
64
65 /* Write new GPIO configuration register value */
66 buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIOCFG_REG);
67 /* Perform SPI transfer */
68 if (max3107_rw(s, (u8 *)buf, NULL, 2)) {
69 dev_err(&s->spi->dev, "SPI transfer GPIO write failed\n");
70 return -EIO;
71 }
72 return 0;
73}
74
75/* GPIO direction to output function */
76static int max3107_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
77 int value)
78{
79 struct max3107_port *s = container_of(chip, struct max3107_port, chip);
80 u16 buf[2]; /* Buffer for SPI transfers */
81
82 if (offset >= MAX3107_GPIO_COUNT) {
83 dev_err(&s->spi->dev, "Invalid GPIO\n");
84 return -EINVAL;
85 }
86
87 /* Read current GPIO configuration and data registers */
88 buf[0] = MAX3107_GPIOCFG_REG;
89 buf[1] = MAX3107_GPIODATA_REG;
90 /* Perform SPI transfer */
91 if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 4)) {
92 dev_err(&s->spi->dev, "SPI transfer gpio failed\n");
93 return -EIO;
94 }
95 buf[0] &= MAX3107_SPI_RX_DATA_MASK;
96 buf[1] &= MAX3107_SPI_RX_DATA_MASK;
97
98 /* Set GPIO to output */
99 buf[0] |= (0x0001 << offset);
100 /* Set value */
101 if (value)
102 buf[1] |= (0x0001 << offset);
103 else
104 buf[1] &= ~(0x0001 << offset);
105
106 /* Write new GPIO configuration and data register values */
107 buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIOCFG_REG);
108 buf[1] |= (MAX3107_WRITE_BIT | MAX3107_GPIODATA_REG);
109 /* Perform SPI transfer */
110 if (max3107_rw(s, (u8 *)buf, NULL, 4)) {
111 dev_err(&s->spi->dev,
112 "SPI transfer for GPIO conf data w failed\n");
113 return -EIO;
114 }
115 return 0;
116}
117
118/* GPIO value query function */
119static int max3107_gpio_get(struct gpio_chip *chip, unsigned offset)
120{
121 struct max3107_port *s = container_of(chip, struct max3107_port, chip);
122 u16 buf[1]; /* Buffer for SPI transfer */
123
124 if (offset >= MAX3107_GPIO_COUNT) {
125 dev_err(&s->spi->dev, "Invalid GPIO\n");
126 return -EINVAL;
127 }
128
129 /* Read current GPIO data register */
130 buf[0] = MAX3107_GPIODATA_REG;
131 /* Perform SPI transfer */
132 if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
133 dev_err(&s->spi->dev, "SPI transfer GPIO data r failed\n");
134 return -EIO;
135 }
136 buf[0] &= MAX3107_SPI_RX_DATA_MASK;
137
138 /* Return value */
139 return buf[0] & (0x0001 << offset);
140}
141
142/* GPIO value set function */
143static void max3107_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
144{
145 struct max3107_port *s = container_of(chip, struct max3107_port, chip);
146 u16 buf[2]; /* Buffer for SPI transfers */
147
148 if (offset >= MAX3107_GPIO_COUNT) {
149 dev_err(&s->spi->dev, "Invalid GPIO\n");
150 return;
151 }
152
153 /* Read current GPIO configuration registers*/
154 buf[0] = MAX3107_GPIODATA_REG;
155 buf[1] = MAX3107_GPIOCFG_REG;
156 /* Perform SPI transfer */
157 if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 4)) {
158 dev_err(&s->spi->dev,
159 "SPI transfer for GPIO data and config read failed\n");
160 return;
161 }
162 buf[0] &= MAX3107_SPI_RX_DATA_MASK;
163 buf[1] &= MAX3107_SPI_RX_DATA_MASK;
164
165 if (!(buf[1] & (0x0001 << offset))) {
166 /* Configured as input, can't set value */
167 dev_warn(&s->spi->dev,
168 "Trying to set value for input GPIO\n");
169 return;
170 }
171
172 /* Set value */
173 if (value)
174 buf[0] |= (0x0001 << offset);
175 else
176 buf[0] &= ~(0x0001 << offset);
177
178 /* Write new GPIO data register value */
179 buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIODATA_REG);
180 /* Perform SPI transfer */
181 if (max3107_rw(s, (u8 *)buf, NULL, 2))
182 dev_err(&s->spi->dev, "SPI transfer GPIO data w failed\n");
183}
184
185/* GPIO chip data */
186static struct gpio_chip max3107_gpio_chip = {
187 .owner = THIS_MODULE,
188 .direction_input = max3107_gpio_direction_in,
189 .direction_output = max3107_gpio_direction_out,
190 .get = max3107_gpio_get,
191 .set = max3107_gpio_set,
192 .can_sleep = 1,
193 .base = MAX3107_GPIO_BASE,
194 .ngpio = MAX3107_GPIO_COUNT,
195};
196
197/**
198 * max3107_aava_reset - reset on AAVA systems
199 * @spi: The SPI device we are probing
200 *
201 * Reset the device ready for probing.
202 */
203
204static int max3107_aava_reset(struct spi_device *spi)
205{
206 /* Reset the chip */
207 if (gpio_request(MAX3107_RESET_GPIO, "max3107")) {
208 pr_err("Requesting RESET GPIO failed\n");
209 return -EIO;
210 }
211 if (gpio_direction_output(MAX3107_RESET_GPIO, 0)) {
212 pr_err("Setting RESET GPIO to 0 failed\n");
213 gpio_free(MAX3107_RESET_GPIO);
214 return -EIO;
215 }
216 msleep(MAX3107_RESET_DELAY);
217 if (gpio_direction_output(MAX3107_RESET_GPIO, 1)) {
218 pr_err("Setting RESET GPIO to 1 failed\n");
219 gpio_free(MAX3107_RESET_GPIO);
220 return -EIO;
221 }
222 gpio_free(MAX3107_RESET_GPIO);
223 msleep(MAX3107_WAKEUP_DELAY);
224 return 0;
225}
226
227static int max3107_aava_configure(struct max3107_port *s)
228{
229 int retval;
230
231 /* Initialize GPIO chip data */
232 s->chip = max3107_gpio_chip;
233 s->chip.label = s->spi->modalias;
234 s->chip.dev = &s->spi->dev;
235
236 /* Add GPIO chip */
237 retval = gpiochip_add(&s->chip);
238 if (retval) {
239 dev_err(&s->spi->dev, "Adding GPIO chip failed\n");
240 return retval;
241 }
242
243 /* Temporary fix for EV2 boot problems, set modem reset to 0 */
244 max3107_gpio_direction_out(&s->chip, 3, 0);
245 return 0;
246}
247
248#if 0
249/* This will get enabled once we have the board stuff merged for this
250 specific case */
251
252static const struct baud_table brg13_ext[] = {
253 { 300, MAX3107_BRG13_B300 },
254 { 600, MAX3107_BRG13_B600 },
255 { 1200, MAX3107_BRG13_B1200 },
256 { 2400, MAX3107_BRG13_B2400 },
257 { 4800, MAX3107_BRG13_B4800 },
258 { 9600, MAX3107_BRG13_B9600 },
259 { 19200, MAX3107_BRG13_B19200 },
260 { 57600, MAX3107_BRG13_B57600 },
261 { 115200, MAX3107_BRG13_B115200 },
262 { 230400, MAX3107_BRG13_B230400 },
263 { 460800, MAX3107_BRG13_B460800 },
264 { 921600, MAX3107_BRG13_B921600 },
265 { 0, 0 }
266};
267
268static void max3107_aava_init(struct max3107_port *s)
269{
270 /*override for AAVA SC specific*/
271 if (mrst_platform_id() == MRST_PLATFORM_AAVA_SC) {
272 if (get_koski_build_id() <= KOSKI_EV2)
273 if (s->ext_clk) {
274 s->brg_cfg = MAX3107_BRG13_B9600;
275 s->baud_tbl = (struct baud_table *)brg13_ext;
276 }
277 }
278}
279#endif
280
281static int __devexit max3107_aava_remove(struct spi_device *spi)
282{
283 struct max3107_port *s = dev_get_drvdata(&spi->dev);
284
285 /* Remove GPIO chip */
286 if (gpiochip_remove(&s->chip))
287 dev_warn(&spi->dev, "Removing GPIO chip failed\n");
288
289 /* Then do the default remove */
290 return max3107_remove(spi);
291}
292
293/* Platform data */
294static struct max3107_plat aava_plat_data = {
295 .loopback = 0,
296 .ext_clk = 1,
297/* .init = max3107_aava_init, */
298 .configure = max3107_aava_configure,
299 .hw_suspend = max3107_hw_susp,
300 .polled_mode = 0,
301 .poll_time = 0,
302};
303
304
305static int __devinit max3107_probe_aava(struct spi_device *spi)
306{
307 int err = max3107_aava_reset(spi);
308 if (err < 0)
309 return err;
310 return max3107_probe(spi, &aava_plat_data);
311}
312
313/* Spi driver data */
314static struct spi_driver max3107_driver = {
315 .driver = {
316 .name = "aava-max3107",
317 .bus = &spi_bus_type,
318 .owner = THIS_MODULE,
319 },
320 .probe = max3107_probe_aava,
321 .remove = __devexit_p(max3107_aava_remove),
322 .suspend = max3107_suspend,
323 .resume = max3107_resume,
324};
325
326/* Driver init function */
327static int __init max3107_init(void)
328{
329 return spi_register_driver(&max3107_driver);
330}
331
332/* Driver exit function */
333static void __exit max3107_exit(void)
334{
335 spi_unregister_driver(&max3107_driver);
336}
337
338module_init(max3107_init);
339module_exit(max3107_exit);
340
341MODULE_DESCRIPTION("MAX3107 driver");
342MODULE_AUTHOR("Aavamobile");
343MODULE_ALIAS("aava-max3107-spi");
344MODULE_LICENSE("GPL v2");