arcnet: Remove pointer comparisons to NULL
[linux/fpc-iii.git] / drivers / gpio / gpio-mpc5200.c
blob4c542153e9234a0fecfada2e9da67df9ad028f6a
1 /*
2 * MPC52xx gpio driver
4 * Copyright (c) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/of.h>
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/of_gpio.h>
24 #include <linux/io.h>
25 #include <linux/of_platform.h>
26 #include <linux/module.h>
28 #include <asm/gpio.h>
29 #include <asm/mpc52xx.h>
30 #include <sysdev/fsl_soc.h>
32 static DEFINE_SPINLOCK(gpio_lock);
34 struct mpc52xx_gpiochip {
35 struct of_mm_gpio_chip mmchip;
36 unsigned int shadow_dvo;
37 unsigned int shadow_gpioe;
38 unsigned int shadow_ddr;
42 * GPIO LIB API implementation for wakeup GPIOs.
44 * There's a maximum of 8 wakeup GPIOs. Which of these are available
45 * for use depends on your board setup.
47 * 0 -> GPIO_WKUP_7
48 * 1 -> GPIO_WKUP_6
49 * 2 -> PSC6_1
50 * 3 -> PSC6_0
51 * 4 -> ETH_17
52 * 5 -> PSC3_9
53 * 6 -> PSC2_4
54 * 7 -> PSC1_4
57 static int mpc52xx_wkup_gpio_get(struct gpio_chip *gc, unsigned int gpio)
59 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
60 struct mpc52xx_gpio_wkup __iomem *regs = mm_gc->regs;
61 unsigned int ret;
63 ret = (in_8(&regs->wkup_ival) >> (7 - gpio)) & 1;
65 pr_debug("%s: gpio: %d ret: %d\n", __func__, gpio, ret);
67 return ret;
70 static inline void
71 __mpc52xx_wkup_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
73 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
74 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
75 struct mpc52xx_gpiochip, mmchip);
76 struct mpc52xx_gpio_wkup __iomem *regs = mm_gc->regs;
78 if (val)
79 chip->shadow_dvo |= 1 << (7 - gpio);
80 else
81 chip->shadow_dvo &= ~(1 << (7 - gpio));
83 out_8(&regs->wkup_dvo, chip->shadow_dvo);
86 static void
87 mpc52xx_wkup_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
89 unsigned long flags;
91 spin_lock_irqsave(&gpio_lock, flags);
93 __mpc52xx_wkup_gpio_set(gc, gpio, val);
95 spin_unlock_irqrestore(&gpio_lock, flags);
97 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
100 static int mpc52xx_wkup_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
102 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
103 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
104 struct mpc52xx_gpiochip, mmchip);
105 struct mpc52xx_gpio_wkup __iomem *regs = mm_gc->regs;
106 unsigned long flags;
108 spin_lock_irqsave(&gpio_lock, flags);
110 /* set the direction */
111 chip->shadow_ddr &= ~(1 << (7 - gpio));
112 out_8(&regs->wkup_ddr, chip->shadow_ddr);
114 /* and enable the pin */
115 chip->shadow_gpioe |= 1 << (7 - gpio);
116 out_8(&regs->wkup_gpioe, chip->shadow_gpioe);
118 spin_unlock_irqrestore(&gpio_lock, flags);
120 return 0;
123 static int
124 mpc52xx_wkup_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
126 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
127 struct mpc52xx_gpio_wkup __iomem *regs = mm_gc->regs;
128 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
129 struct mpc52xx_gpiochip, mmchip);
130 unsigned long flags;
132 spin_lock_irqsave(&gpio_lock, flags);
134 __mpc52xx_wkup_gpio_set(gc, gpio, val);
136 /* Then set direction */
137 chip->shadow_ddr |= 1 << (7 - gpio);
138 out_8(&regs->wkup_ddr, chip->shadow_ddr);
140 /* Finally enable the pin */
141 chip->shadow_gpioe |= 1 << (7 - gpio);
142 out_8(&regs->wkup_gpioe, chip->shadow_gpioe);
144 spin_unlock_irqrestore(&gpio_lock, flags);
146 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
148 return 0;
151 static int mpc52xx_wkup_gpiochip_probe(struct platform_device *ofdev)
153 struct mpc52xx_gpiochip *chip;
154 struct mpc52xx_gpio_wkup __iomem *regs;
155 struct gpio_chip *gc;
156 int ret;
158 chip = devm_kzalloc(&ofdev->dev, sizeof(*chip), GFP_KERNEL);
159 if (!chip)
160 return -ENOMEM;
162 platform_set_drvdata(ofdev, chip);
164 gc = &chip->mmchip.gc;
166 gc->ngpio = 8;
167 gc->direction_input = mpc52xx_wkup_gpio_dir_in;
168 gc->direction_output = mpc52xx_wkup_gpio_dir_out;
169 gc->get = mpc52xx_wkup_gpio_get;
170 gc->set = mpc52xx_wkup_gpio_set;
172 ret = of_mm_gpiochip_add(ofdev->dev.of_node, &chip->mmchip);
173 if (ret)
174 return ret;
176 regs = chip->mmchip.regs;
177 chip->shadow_gpioe = in_8(&regs->wkup_gpioe);
178 chip->shadow_ddr = in_8(&regs->wkup_ddr);
179 chip->shadow_dvo = in_8(&regs->wkup_dvo);
181 return 0;
184 static int mpc52xx_gpiochip_remove(struct platform_device *ofdev)
186 struct mpc52xx_gpiochip *chip = platform_get_drvdata(ofdev);
188 of_mm_gpiochip_remove(&chip->mmchip);
190 return 0;
193 static const struct of_device_id mpc52xx_wkup_gpiochip_match[] = {
194 { .compatible = "fsl,mpc5200-gpio-wkup", },
198 static struct platform_driver mpc52xx_wkup_gpiochip_driver = {
199 .driver = {
200 .name = "mpc5200-gpio-wkup",
201 .of_match_table = mpc52xx_wkup_gpiochip_match,
203 .probe = mpc52xx_wkup_gpiochip_probe,
204 .remove = mpc52xx_gpiochip_remove,
208 * GPIO LIB API implementation for simple GPIOs
210 * There's a maximum of 32 simple GPIOs. Which of these are available
211 * for use depends on your board setup.
212 * The numbering reflects the bit numbering in the port registers:
214 * 0..1 > reserved
215 * 2..3 > IRDA
216 * 4..7 > ETHR
217 * 8..11 > reserved
218 * 12..15 > USB
219 * 16..17 > reserved
220 * 18..23 > PSC3
221 * 24..27 > PSC2
222 * 28..31 > PSC1
224 static int mpc52xx_simple_gpio_get(struct gpio_chip *gc, unsigned int gpio)
226 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
227 struct mpc52xx_gpio __iomem *regs = mm_gc->regs;
228 unsigned int ret;
230 ret = (in_be32(&regs->simple_ival) >> (31 - gpio)) & 1;
232 return ret;
235 static inline void
236 __mpc52xx_simple_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
238 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
239 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
240 struct mpc52xx_gpiochip, mmchip);
241 struct mpc52xx_gpio __iomem *regs = mm_gc->regs;
243 if (val)
244 chip->shadow_dvo |= 1 << (31 - gpio);
245 else
246 chip->shadow_dvo &= ~(1 << (31 - gpio));
247 out_be32(&regs->simple_dvo, chip->shadow_dvo);
250 static void
251 mpc52xx_simple_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
253 unsigned long flags;
255 spin_lock_irqsave(&gpio_lock, flags);
257 __mpc52xx_simple_gpio_set(gc, gpio, val);
259 spin_unlock_irqrestore(&gpio_lock, flags);
261 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
264 static int mpc52xx_simple_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
266 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
267 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
268 struct mpc52xx_gpiochip, mmchip);
269 struct mpc52xx_gpio __iomem *regs = mm_gc->regs;
270 unsigned long flags;
272 spin_lock_irqsave(&gpio_lock, flags);
274 /* set the direction */
275 chip->shadow_ddr &= ~(1 << (31 - gpio));
276 out_be32(&regs->simple_ddr, chip->shadow_ddr);
278 /* and enable the pin */
279 chip->shadow_gpioe |= 1 << (31 - gpio);
280 out_be32(&regs->simple_gpioe, chip->shadow_gpioe);
282 spin_unlock_irqrestore(&gpio_lock, flags);
284 return 0;
287 static int
288 mpc52xx_simple_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
290 struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
291 struct mpc52xx_gpiochip *chip = container_of(mm_gc,
292 struct mpc52xx_gpiochip, mmchip);
293 struct mpc52xx_gpio __iomem *regs = mm_gc->regs;
294 unsigned long flags;
296 spin_lock_irqsave(&gpio_lock, flags);
298 /* First set initial value */
299 __mpc52xx_simple_gpio_set(gc, gpio, val);
301 /* Then set direction */
302 chip->shadow_ddr |= 1 << (31 - gpio);
303 out_be32(&regs->simple_ddr, chip->shadow_ddr);
305 /* Finally enable the pin */
306 chip->shadow_gpioe |= 1 << (31 - gpio);
307 out_be32(&regs->simple_gpioe, chip->shadow_gpioe);
309 spin_unlock_irqrestore(&gpio_lock, flags);
311 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
313 return 0;
316 static int mpc52xx_simple_gpiochip_probe(struct platform_device *ofdev)
318 struct mpc52xx_gpiochip *chip;
319 struct gpio_chip *gc;
320 struct mpc52xx_gpio __iomem *regs;
321 int ret;
323 chip = devm_kzalloc(&ofdev->dev, sizeof(*chip), GFP_KERNEL);
324 if (!chip)
325 return -ENOMEM;
327 platform_set_drvdata(ofdev, chip);
329 gc = &chip->mmchip.gc;
331 gc->ngpio = 32;
332 gc->direction_input = mpc52xx_simple_gpio_dir_in;
333 gc->direction_output = mpc52xx_simple_gpio_dir_out;
334 gc->get = mpc52xx_simple_gpio_get;
335 gc->set = mpc52xx_simple_gpio_set;
337 ret = of_mm_gpiochip_add(ofdev->dev.of_node, &chip->mmchip);
338 if (ret)
339 return ret;
341 regs = chip->mmchip.regs;
342 chip->shadow_gpioe = in_be32(&regs->simple_gpioe);
343 chip->shadow_ddr = in_be32(&regs->simple_ddr);
344 chip->shadow_dvo = in_be32(&regs->simple_dvo);
346 return 0;
349 static const struct of_device_id mpc52xx_simple_gpiochip_match[] = {
350 { .compatible = "fsl,mpc5200-gpio", },
354 static struct platform_driver mpc52xx_simple_gpiochip_driver = {
355 .driver = {
356 .name = "mpc5200-gpio",
357 .of_match_table = mpc52xx_simple_gpiochip_match,
359 .probe = mpc52xx_simple_gpiochip_probe,
360 .remove = mpc52xx_gpiochip_remove,
363 static int __init mpc52xx_gpio_init(void)
365 if (platform_driver_register(&mpc52xx_wkup_gpiochip_driver))
366 printk(KERN_ERR "Unable to register wakeup GPIO driver\n");
368 if (platform_driver_register(&mpc52xx_simple_gpiochip_driver))
369 printk(KERN_ERR "Unable to register simple GPIO driver\n");
371 return 0;
374 /* Make sure we get initialised before anyone else tries to use us */
375 subsys_initcall(mpc52xx_gpio_init);
377 static void __exit mpc52xx_gpio_exit(void)
379 platform_driver_unregister(&mpc52xx_wkup_gpiochip_driver);
381 platform_driver_unregister(&mpc52xx_simple_gpiochip_driver);
383 module_exit(mpc52xx_gpio_exit);
385 MODULE_DESCRIPTION("Freescale MPC52xx gpio driver");
386 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de");
387 MODULE_LICENSE("GPL v2");