diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-28 18:54:04 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-28 18:54:04 -0400 |
commit | b779b332d0e1ef68f40867948ae5526a3e925163 (patch) | |
tree | d2fc8bb455d696fbdb288055ce0a4f0cfcee31fd /drivers/gpio/vx855_gpio.c | |
parent | a0cadc2777a71b1fde62e6417284b38e52128e88 (diff) | |
parent | 0f48285755991b73c14b6eeeee464590f490ac25 (diff) |
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6: (73 commits)
power: Revert "power_supply: Mark twl4030_charger as broken"
mfd: Fix a memory leak when unload mc13xxx-core module
mfd: Fix resource reclaim for max8998
mfd: Remove unneeded ret value checking for max8998 register updates
mfd: Add free max8998->ono irq in max8998_irq_exit()
mfd: Fix resource reclaim in pcf50633_remove()
omap4: pandaboard: fix up mmc card detect logic
mfd: Fix ezx_pcap_probe error path
mfd: Fix off-by-one value range checking for tps6507x
mfd: Remove __devinitdata from tc6393xb_mmc_resources
mfd: Add WM831x SPI support
mfd: Factor out WM831x I2C I/O from the core driver
mfd: Remove DEBUG defines from mc13xxx-core
mfd: Fix jz4740_adc_set_enabled
mfd: Add TPS658621C device ID
mfd: Fix twl-irq function declaration warnings
regulator: max8998 BUCK1/2 voltage change with use of GPIOs
mfd: Voltages and GPIOs platform_data definitions for max8998
regulator: max8998 BUCK1/2 internal voltages and indexes defined
mfd: Support for ICs compliant with max8998
...
Diffstat (limited to 'drivers/gpio/vx855_gpio.c')
-rw-r--r-- | drivers/gpio/vx855_gpio.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/gpio/vx855_gpio.c b/drivers/gpio/vx855_gpio.c new file mode 100644 index 000000000000..8a98ee5d5f6c --- /dev/null +++ b/drivers/gpio/vx855_gpio.c | |||
@@ -0,0 +1,332 @@ | |||
1 | /* | ||
2 | * Linux GPIOlib driver for the VIA VX855 integrated southbridge GPIO | ||
3 | * | ||
4 | * Copyright (C) 2009 VIA Technologies, Inc. | ||
5 | * Copyright (C) 2010 One Laptop per Child | ||
6 | * Author: Harald Welte <HaraldWelte@viatech.com> | ||
7 | * All rights reserved. | ||
8 | * | ||
9 | * This program is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU General Public License as | ||
11 | * published by the Free Software Foundation; either version 2 of | ||
12 | * the License, or (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., 59 Temple Place, Suite 330, Boston, | ||
22 | * MA 02111-1307 USA | ||
23 | * | ||
24 | */ | ||
25 | |||
26 | #include <linux/kernel.h> | ||
27 | #include <linux/module.h> | ||
28 | #include <linux/gpio.h> | ||
29 | #include <linux/device.h> | ||
30 | #include <linux/platform_device.h> | ||
31 | #include <linux/pci.h> | ||
32 | #include <linux/io.h> | ||
33 | |||
34 | #define MODULE_NAME "vx855_gpio" | ||
35 | |||
36 | /* The VX855 south bridge has the following GPIO pins: | ||
37 | * GPI 0...13 General Purpose Input | ||
38 | * GPO 0...12 General Purpose Output | ||
39 | * GPIO 0...14 General Purpose I/O (Open-Drain) | ||
40 | */ | ||
41 | |||
42 | #define NR_VX855_GPI 14 | ||
43 | #define NR_VX855_GPO 13 | ||
44 | #define NR_VX855_GPIO 15 | ||
45 | |||
46 | #define NR_VX855_GPInO (NR_VX855_GPI + NR_VX855_GPO) | ||
47 | #define NR_VX855_GP (NR_VX855_GPI + NR_VX855_GPO + NR_VX855_GPIO) | ||
48 | |||
49 | struct vx855_gpio { | ||
50 | struct gpio_chip gpio; | ||
51 | spinlock_t lock; | ||
52 | u32 io_gpi; | ||
53 | u32 io_gpo; | ||
54 | bool gpi_reserved; | ||
55 | bool gpo_reserved; | ||
56 | }; | ||
57 | |||
58 | /* resolve a GPIx into the corresponding bit position */ | ||
59 | static inline u_int32_t gpi_i_bit(int i) | ||
60 | { | ||
61 | if (i < 10) | ||
62 | return 1 << i; | ||
63 | else | ||
64 | return 1 << (i + 14); | ||
65 | } | ||
66 | |||
67 | static inline u_int32_t gpo_o_bit(int i) | ||
68 | { | ||
69 | if (i < 11) | ||
70 | return 1 << i; | ||
71 | else | ||
72 | return 1 << (i + 14); | ||
73 | } | ||
74 | |||
75 | static inline u_int32_t gpio_i_bit(int i) | ||
76 | { | ||
77 | if (i < 14) | ||
78 | return 1 << (i + 10); | ||
79 | else | ||
80 | return 1 << (i + 14); | ||
81 | } | ||
82 | |||
83 | static inline u_int32_t gpio_o_bit(int i) | ||
84 | { | ||
85 | if (i < 14) | ||
86 | return 1 << (i + 11); | ||
87 | else | ||
88 | return 1 << (i + 13); | ||
89 | } | ||
90 | |||
91 | /* Mapping betwee numeric GPIO ID and the actual GPIO hardware numbering: | ||
92 | * 0..13 GPI 0..13 | ||
93 | * 14..26 GPO 0..12 | ||
94 | * 27..41 GPIO 0..14 | ||
95 | */ | ||
96 | |||
97 | static int vx855gpio_direction_input(struct gpio_chip *gpio, | ||
98 | unsigned int nr) | ||
99 | { | ||
100 | struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio); | ||
101 | unsigned long flags; | ||
102 | u_int32_t reg_out; | ||
103 | |||
104 | /* Real GPI bits are always in input direction */ | ||
105 | if (nr < NR_VX855_GPI) | ||
106 | return 0; | ||
107 | |||
108 | /* Real GPO bits cannot be put in output direction */ | ||
109 | if (nr < NR_VX855_GPInO) | ||
110 | return -EINVAL; | ||
111 | |||
112 | /* Open Drain GPIO have to be set to one */ | ||
113 | spin_lock_irqsave(&vg->lock, flags); | ||
114 | reg_out = inl(vg->io_gpo); | ||
115 | reg_out |= gpio_o_bit(nr - NR_VX855_GPInO); | ||
116 | outl(reg_out, vg->io_gpo); | ||
117 | spin_unlock_irqrestore(&vg->lock, flags); | ||
118 | |||
119 | return 0; | ||
120 | } | ||
121 | |||
122 | static int vx855gpio_get(struct gpio_chip *gpio, unsigned int nr) | ||
123 | { | ||
124 | struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio); | ||
125 | u_int32_t reg_in; | ||
126 | int ret = 0; | ||
127 | |||
128 | if (nr < NR_VX855_GPI) { | ||
129 | reg_in = inl(vg->io_gpi); | ||
130 | if (reg_in & gpi_i_bit(nr)) | ||
131 | ret = 1; | ||
132 | } else if (nr < NR_VX855_GPInO) { | ||
133 | /* GPO don't have an input bit, we need to read it | ||
134 | * back from the output register */ | ||
135 | reg_in = inl(vg->io_gpo); | ||
136 | if (reg_in & gpo_o_bit(nr - NR_VX855_GPI)) | ||
137 | ret = 1; | ||
138 | } else { | ||
139 | reg_in = inl(vg->io_gpi); | ||
140 | if (reg_in & gpio_i_bit(nr - NR_VX855_GPInO)) | ||
141 | ret = 1; | ||
142 | } | ||
143 | |||
144 | return ret; | ||
145 | } | ||
146 | |||
147 | static void vx855gpio_set(struct gpio_chip *gpio, unsigned int nr, | ||
148 | int val) | ||
149 | { | ||
150 | struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio); | ||
151 | unsigned long flags; | ||
152 | u_int32_t reg_out; | ||
153 | |||
154 | /* True GPI cannot be switched to output mode */ | ||
155 | if (nr < NR_VX855_GPI) | ||
156 | return; | ||
157 | |||
158 | spin_lock_irqsave(&vg->lock, flags); | ||
159 | reg_out = inl(vg->io_gpo); | ||
160 | if (nr < NR_VX855_GPInO) { | ||
161 | if (val) | ||
162 | reg_out |= gpo_o_bit(nr - NR_VX855_GPI); | ||
163 | else | ||
164 | reg_out &= ~gpo_o_bit(nr - NR_VX855_GPI); | ||
165 | } else { | ||
166 | if (val) | ||
167 | reg_out |= gpio_o_bit(nr - NR_VX855_GPInO); | ||
168 | else | ||
169 | reg_out &= ~gpio_o_bit(nr - NR_VX855_GPInO); | ||
170 | } | ||
171 | outl(reg_out, vg->io_gpo); | ||
172 | spin_unlock_irqrestore(&vg->lock, flags); | ||
173 | } | ||
174 | |||
175 | static int vx855gpio_direction_output(struct gpio_chip *gpio, | ||
176 | unsigned int nr, int val) | ||
177 | { | ||
178 | /* True GPI cannot be switched to output mode */ | ||
179 | if (nr < NR_VX855_GPI) | ||
180 | return -EINVAL; | ||
181 | |||
182 | /* True GPO don't need to be switched to output mode, | ||
183 | * and GPIO are open-drain, i.e. also need no switching, | ||
184 | * so all we do is set the level */ | ||
185 | vx855gpio_set(gpio, nr, val); | ||
186 | |||
187 | return 0; | ||
188 | } | ||
189 | |||
190 | static const char *vx855gpio_names[NR_VX855_GP] = { | ||
191 | "VX855_GPI0", "VX855_GPI1", "VX855_GPI2", "VX855_GPI3", "VX855_GPI4", | ||
192 | "VX855_GPI5", "VX855_GPI6", "VX855_GPI7", "VX855_GPI8", "VX855_GPI9", | ||
193 | "VX855_GPI10", "VX855_GPI11", "VX855_GPI12", "VX855_GPI13", | ||
194 | "VX855_GPO0", "VX855_GPO1", "VX855_GPO2", "VX855_GPO3", "VX855_GPO4", | ||
195 | "VX855_GPO5", "VX855_GPO6", "VX855_GPO7", "VX855_GPO8", "VX855_GPO9", | ||
196 | "VX855_GPO10", "VX855_GPO11", "VX855_GPO12", | ||
197 | "VX855_GPIO0", "VX855_GPIO1", "VX855_GPIO2", "VX855_GPIO3", | ||
198 | "VX855_GPIO4", "VX855_GPIO5", "VX855_GPIO6", "VX855_GPIO7", | ||
199 | "VX855_GPIO8", "VX855_GPIO9", "VX855_GPIO10", "VX855_GPIO11", | ||
200 | "VX855_GPIO12", "VX855_GPIO13", "VX855_GPIO14" | ||
201 | }; | ||
202 | |||
203 | static void vx855gpio_gpio_setup(struct vx855_gpio *vg) | ||
204 | { | ||
205 | struct gpio_chip *c = &vg->gpio; | ||
206 | |||
207 | c->label = "VX855 South Bridge"; | ||
208 | c->owner = THIS_MODULE; | ||
209 | c->direction_input = vx855gpio_direction_input; | ||
210 | c->direction_output = vx855gpio_direction_output; | ||
211 | c->get = vx855gpio_get; | ||
212 | c->set = vx855gpio_set; | ||
213 | c->dbg_show = NULL; | ||
214 | c->base = 0; | ||
215 | c->ngpio = NR_VX855_GP; | ||
216 | c->can_sleep = 0; | ||
217 | c->names = vx855gpio_names; | ||
218 | } | ||
219 | |||
220 | /* This platform device is ordinarily registered by the vx855 mfd driver */ | ||
221 | static __devinit int vx855gpio_probe(struct platform_device *pdev) | ||
222 | { | ||
223 | struct resource *res_gpi; | ||
224 | struct resource *res_gpo; | ||
225 | struct vx855_gpio *vg; | ||
226 | int ret; | ||
227 | |||
228 | res_gpi = platform_get_resource(pdev, IORESOURCE_IO, 0); | ||
229 | res_gpo = platform_get_resource(pdev, IORESOURCE_IO, 1); | ||
230 | if (!res_gpi || !res_gpo) | ||
231 | return -EBUSY; | ||
232 | |||
233 | vg = kzalloc(sizeof(*vg), GFP_KERNEL); | ||
234 | if (!vg) | ||
235 | return -ENOMEM; | ||
236 | |||
237 | platform_set_drvdata(pdev, vg); | ||
238 | |||
239 | dev_info(&pdev->dev, "found VX855 GPIO controller\n"); | ||
240 | vg->io_gpi = res_gpi->start; | ||
241 | vg->io_gpo = res_gpo->start; | ||
242 | spin_lock_init(&vg->lock); | ||
243 | |||
244 | /* | ||
245 | * A single byte is used to control various GPIO ports on the VX855, | ||
246 | * and in the case of the OLPC XO-1.5, some of those ports are used | ||
247 | * for switches that are interpreted and exposed through ACPI. ACPI | ||
248 | * will have reserved the region, so our own reservation will not | ||
249 | * succeed. Ignore and continue. | ||
250 | */ | ||
251 | |||
252 | if (!request_region(res_gpi->start, resource_size(res_gpi), | ||
253 | MODULE_NAME "_gpi")) | ||
254 | dev_warn(&pdev->dev, | ||
255 | "GPI I/O resource busy, probably claimed by ACPI\n"); | ||
256 | else | ||
257 | vg->gpi_reserved = true; | ||
258 | |||
259 | if (!request_region(res_gpo->start, resource_size(res_gpo), | ||
260 | MODULE_NAME "_gpo")) | ||
261 | dev_warn(&pdev->dev, | ||
262 | "GPO I/O resource busy, probably claimed by ACPI\n"); | ||
263 | else | ||
264 | vg->gpo_reserved = true; | ||
265 | |||
266 | vx855gpio_gpio_setup(vg); | ||
267 | |||
268 | ret = gpiochip_add(&vg->gpio); | ||
269 | if (ret) { | ||
270 | dev_err(&pdev->dev, "failed to register GPIOs\n"); | ||
271 | goto out_release; | ||
272 | } | ||
273 | |||
274 | return 0; | ||
275 | |||
276 | out_release: | ||
277 | if (vg->gpi_reserved) | ||
278 | release_region(res_gpi->start, resource_size(res_gpi)); | ||
279 | if (vg->gpo_reserved) | ||
280 | release_region(res_gpi->start, resource_size(res_gpo)); | ||
281 | platform_set_drvdata(pdev, NULL); | ||
282 | kfree(vg); | ||
283 | return ret; | ||
284 | } | ||
285 | |||
286 | static int __devexit vx855gpio_remove(struct platform_device *pdev) | ||
287 | { | ||
288 | struct vx855_gpio *vg = platform_get_drvdata(pdev); | ||
289 | struct resource *res; | ||
290 | |||
291 | if (gpiochip_remove(&vg->gpio)) | ||
292 | dev_err(&pdev->dev, "unable to remove gpio_chip?\n"); | ||
293 | |||
294 | if (vg->gpi_reserved) { | ||
295 | res = platform_get_resource(pdev, IORESOURCE_IO, 0); | ||
296 | release_region(res->start, resource_size(res)); | ||
297 | } | ||
298 | if (vg->gpo_reserved) { | ||
299 | res = platform_get_resource(pdev, IORESOURCE_IO, 1); | ||
300 | release_region(res->start, resource_size(res)); | ||
301 | } | ||
302 | |||
303 | platform_set_drvdata(pdev, NULL); | ||
304 | kfree(vg); | ||
305 | return 0; | ||
306 | } | ||
307 | |||
308 | static struct platform_driver vx855gpio_driver = { | ||
309 | .driver = { | ||
310 | .name = MODULE_NAME, | ||
311 | .owner = THIS_MODULE, | ||
312 | }, | ||
313 | .probe = vx855gpio_probe, | ||
314 | .remove = __devexit_p(vx855gpio_remove), | ||
315 | }; | ||
316 | |||
317 | static int vx855gpio_init(void) | ||
318 | { | ||
319 | return platform_driver_register(&vx855gpio_driver); | ||
320 | } | ||
321 | module_init(vx855gpio_init); | ||
322 | |||
323 | static void vx855gpio_exit(void) | ||
324 | { | ||
325 | platform_driver_unregister(&vx855gpio_driver); | ||
326 | } | ||
327 | module_exit(vx855gpio_exit); | ||
328 | |||
329 | MODULE_LICENSE("GPL"); | ||
330 | MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>"); | ||
331 | MODULE_DESCRIPTION("GPIO driver for the VIA VX855 chipset"); | ||
332 | MODULE_ALIAS("platform:vx855_gpio"); | ||