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d87964c4 BD |
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2 | /* linux/arch/arm/plat-s3c/pm-gpio.c | |
3 | * | |
4 | * Copyright 2008 Openmoko, Inc. | |
5 | * Copyright 2008 Simtec Electronics | |
6 | * Ben Dooks <ben@simtec.co.uk> | |
7 | * http://armlinux.simtec.co.uk/ | |
8 | * | |
9 | * S3C series GPIO PM code | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License version 2 as | |
13 | * published by the Free Software Foundation. | |
14 | */ | |
15 | ||
16 | #include <linux/kernel.h> | |
edbaa603 | 17 | #include <linux/device.h> |
d87964c4 BD |
18 | #include <linux/init.h> |
19 | #include <linux/io.h> | |
20 | #include <linux/gpio.h> | |
21 | ||
785acec3 | 22 | #if defined(CONFIG_ARCH_S3C24XX) || defined(CONFIG_ARCH_S3C64XX) |
b0161caa | 23 | #include <mach/gpio-samsung.h> |
785acec3 SK |
24 | #endif |
25 | ||
e856bb1f | 26 | #include <plat/gpio-core.h> |
d87964c4 BD |
27 | #include <plat/pm.h> |
28 | ||
29 | /* PM GPIO helpers */ | |
30 | ||
31 | #define OFFS_CON (0x00) | |
32 | #define OFFS_DAT (0x04) | |
33 | #define OFFS_UP (0x08) | |
34 | ||
782d8a3c | 35 | static void samsung_gpio_pm_1bit_save(struct samsung_gpio_chip *chip) |
d87964c4 BD |
36 | { |
37 | chip->pm_save[0] = __raw_readl(chip->base + OFFS_CON); | |
38 | chip->pm_save[1] = __raw_readl(chip->base + OFFS_DAT); | |
39 | } | |
40 | ||
782d8a3c | 41 | static void samsung_gpio_pm_1bit_resume(struct samsung_gpio_chip *chip) |
d87964c4 BD |
42 | { |
43 | void __iomem *base = chip->base; | |
44 | u32 old_gpcon = __raw_readl(base + OFFS_CON); | |
45 | u32 old_gpdat = __raw_readl(base + OFFS_DAT); | |
46 | u32 gps_gpcon = chip->pm_save[0]; | |
47 | u32 gps_gpdat = chip->pm_save[1]; | |
48 | u32 gpcon; | |
49 | ||
50 | /* GPACON only has one bit per control / data and no PULLUPs. | |
51 | * GPACON[x] = 0 => Output, 1 => SFN */ | |
52 | ||
53 | /* first set all SFN bits to SFN */ | |
54 | ||
55 | gpcon = old_gpcon | gps_gpcon; | |
56 | __raw_writel(gpcon, base + OFFS_CON); | |
57 | ||
58 | /* now set all the other bits */ | |
59 | ||
60 | __raw_writel(gps_gpdat, base + OFFS_DAT); | |
61 | __raw_writel(gps_gpcon, base + OFFS_CON); | |
62 | ||
63 | S3C_PMDBG("%s: CON %08x => %08x, DAT %08x => %08x\n", | |
64 | chip->chip.label, old_gpcon, gps_gpcon, old_gpdat, gps_gpdat); | |
65 | } | |
66 | ||
782d8a3c KK |
67 | struct samsung_gpio_pm samsung_gpio_pm_1bit = { |
68 | .save = samsung_gpio_pm_1bit_save, | |
69 | .resume = samsung_gpio_pm_1bit_resume, | |
d87964c4 BD |
70 | }; |
71 | ||
782d8a3c | 72 | static void samsung_gpio_pm_2bit_save(struct samsung_gpio_chip *chip) |
d87964c4 BD |
73 | { |
74 | chip->pm_save[0] = __raw_readl(chip->base + OFFS_CON); | |
75 | chip->pm_save[1] = __raw_readl(chip->base + OFFS_DAT); | |
76 | chip->pm_save[2] = __raw_readl(chip->base + OFFS_UP); | |
77 | } | |
78 | ||
79 | /* Test whether the given masked+shifted bits of an GPIO configuration | |
80 | * are one of the SFN (special function) modes. */ | |
81 | ||
82 | static inline int is_sfn(unsigned long con) | |
83 | { | |
84 | return con >= 2; | |
85 | } | |
86 | ||
87 | /* Test if the given masked+shifted GPIO configuration is an input */ | |
88 | ||
89 | static inline int is_in(unsigned long con) | |
90 | { | |
91 | return con == 0; | |
92 | } | |
93 | ||
94 | /* Test if the given masked+shifted GPIO configuration is an output */ | |
95 | ||
96 | static inline int is_out(unsigned long con) | |
97 | { | |
98 | return con == 1; | |
99 | } | |
100 | ||
101 | /** | |
782d8a3c | 102 | * samsung_gpio_pm_2bit_resume() - restore the given GPIO bank |
d87964c4 BD |
103 | * @chip: The chip information to resume. |
104 | * | |
105 | * Restore one of the GPIO banks that was saved during suspend. This is | |
106 | * not as simple as once thought, due to the possibility of glitches | |
107 | * from the order that the CON and DAT registers are set in. | |
108 | * | |
109 | * The three states the pin can be are {IN,OUT,SFN} which gives us 9 | |
110 | * combinations of changes to check. Three of these, if the pin stays | |
111 | * in the same configuration can be discounted. This leaves us with | |
112 | * the following: | |
113 | * | |
114 | * { IN => OUT } Change DAT first | |
115 | * { IN => SFN } Change CON first | |
116 | * { OUT => SFN } Change CON first, so new data will not glitch | |
117 | * { OUT => IN } Change CON first, so new data will not glitch | |
118 | * { SFN => IN } Change CON first | |
119 | * { SFN => OUT } Change DAT first, so new data will not glitch [1] | |
120 | * | |
121 | * We do not currently deal with the UP registers as these control | |
122 | * weak resistors, so a small delay in change should not need to bring | |
123 | * these into the calculations. | |
124 | * | |
125 | * [1] this assumes that writing to a pin DAT whilst in SFN will set the | |
126 | * state for when it is next output. | |
127 | */ | |
782d8a3c | 128 | static void samsung_gpio_pm_2bit_resume(struct samsung_gpio_chip *chip) |
d87964c4 BD |
129 | { |
130 | void __iomem *base = chip->base; | |
131 | u32 old_gpcon = __raw_readl(base + OFFS_CON); | |
132 | u32 old_gpdat = __raw_readl(base + OFFS_DAT); | |
133 | u32 gps_gpcon = chip->pm_save[0]; | |
134 | u32 gps_gpdat = chip->pm_save[1]; | |
135 | u32 gpcon, old, new, mask; | |
136 | u32 change_mask = 0x0; | |
137 | int nr; | |
138 | ||
139 | /* restore GPIO pull-up settings */ | |
140 | __raw_writel(chip->pm_save[2], base + OFFS_UP); | |
141 | ||
142 | /* Create a change_mask of all the items that need to have | |
143 | * their CON value changed before their DAT value, so that | |
144 | * we minimise the work between the two settings. | |
145 | */ | |
146 | ||
147 | for (nr = 0, mask = 0x03; nr < 32; nr += 2, mask <<= 2) { | |
148 | old = (old_gpcon & mask) >> nr; | |
149 | new = (gps_gpcon & mask) >> nr; | |
150 | ||
151 | /* If there is no change, then skip */ | |
152 | ||
153 | if (old == new) | |
154 | continue; | |
155 | ||
156 | /* If both are special function, then skip */ | |
157 | ||
158 | if (is_sfn(old) && is_sfn(new)) | |
159 | continue; | |
160 | ||
161 | /* Change is IN => OUT, do not change now */ | |
162 | ||
163 | if (is_in(old) && is_out(new)) | |
164 | continue; | |
165 | ||
166 | /* Change is SFN => OUT, do not change now */ | |
167 | ||
168 | if (is_sfn(old) && is_out(new)) | |
169 | continue; | |
170 | ||
171 | /* We should now be at the case of IN=>SFN, | |
172 | * OUT=>SFN, OUT=>IN, SFN=>IN. */ | |
173 | ||
174 | change_mask |= mask; | |
175 | } | |
176 | ||
177 | ||
178 | /* Write the new CON settings */ | |
179 | ||
180 | gpcon = old_gpcon & ~change_mask; | |
181 | gpcon |= gps_gpcon & change_mask; | |
182 | ||
183 | __raw_writel(gpcon, base + OFFS_CON); | |
184 | ||
185 | /* Now change any items that require DAT,CON */ | |
186 | ||
187 | __raw_writel(gps_gpdat, base + OFFS_DAT); | |
188 | __raw_writel(gps_gpcon, base + OFFS_CON); | |
189 | ||
190 | S3C_PMDBG("%s: CON %08x => %08x, DAT %08x => %08x\n", | |
191 | chip->chip.label, old_gpcon, gps_gpcon, old_gpdat, gps_gpdat); | |
192 | } | |
193 | ||
782d8a3c KK |
194 | struct samsung_gpio_pm samsung_gpio_pm_2bit = { |
195 | .save = samsung_gpio_pm_2bit_save, | |
196 | .resume = samsung_gpio_pm_2bit_resume, | |
d87964c4 BD |
197 | }; |
198 | ||
e9d428ee | 199 | #if defined(CONFIG_ARCH_S3C64XX) || defined(CONFIG_PLAT_S5P) |
782d8a3c | 200 | static void samsung_gpio_pm_4bit_save(struct samsung_gpio_chip *chip) |
d87964c4 BD |
201 | { |
202 | chip->pm_save[1] = __raw_readl(chip->base + OFFS_CON); | |
203 | chip->pm_save[2] = __raw_readl(chip->base + OFFS_DAT); | |
204 | chip->pm_save[3] = __raw_readl(chip->base + OFFS_UP); | |
205 | ||
206 | if (chip->chip.ngpio > 8) | |
207 | chip->pm_save[0] = __raw_readl(chip->base - 4); | |
208 | } | |
209 | ||
782d8a3c | 210 | static u32 samsung_gpio_pm_4bit_mask(u32 old_gpcon, u32 gps_gpcon) |
d87964c4 BD |
211 | { |
212 | u32 old, new, mask; | |
213 | u32 change_mask = 0x0; | |
214 | int nr; | |
215 | ||
216 | for (nr = 0, mask = 0x0f; nr < 16; nr += 4, mask <<= 4) { | |
217 | old = (old_gpcon & mask) >> nr; | |
218 | new = (gps_gpcon & mask) >> nr; | |
219 | ||
220 | /* If there is no change, then skip */ | |
221 | ||
222 | if (old == new) | |
223 | continue; | |
224 | ||
225 | /* If both are special function, then skip */ | |
226 | ||
227 | if (is_sfn(old) && is_sfn(new)) | |
228 | continue; | |
229 | ||
230 | /* Change is IN => OUT, do not change now */ | |
231 | ||
232 | if (is_in(old) && is_out(new)) | |
233 | continue; | |
234 | ||
235 | /* Change is SFN => OUT, do not change now */ | |
236 | ||
237 | if (is_sfn(old) && is_out(new)) | |
238 | continue; | |
239 | ||
240 | /* We should now be at the case of IN=>SFN, | |
241 | * OUT=>SFN, OUT=>IN, SFN=>IN. */ | |
242 | ||
243 | change_mask |= mask; | |
244 | } | |
245 | ||
246 | return change_mask; | |
247 | } | |
248 | ||
782d8a3c | 249 | static void samsung_gpio_pm_4bit_con(struct samsung_gpio_chip *chip, int index) |
d87964c4 BD |
250 | { |
251 | void __iomem *con = chip->base + (index * 4); | |
252 | u32 old_gpcon = __raw_readl(con); | |
253 | u32 gps_gpcon = chip->pm_save[index + 1]; | |
254 | u32 gpcon, mask; | |
255 | ||
782d8a3c | 256 | mask = samsung_gpio_pm_4bit_mask(old_gpcon, gps_gpcon); |
d87964c4 BD |
257 | |
258 | gpcon = old_gpcon & ~mask; | |
259 | gpcon |= gps_gpcon & mask; | |
260 | ||
261 | __raw_writel(gpcon, con); | |
262 | } | |
263 | ||
782d8a3c | 264 | static void samsung_gpio_pm_4bit_resume(struct samsung_gpio_chip *chip) |
d87964c4 BD |
265 | { |
266 | void __iomem *base = chip->base; | |
267 | u32 old_gpcon[2]; | |
268 | u32 old_gpdat = __raw_readl(base + OFFS_DAT); | |
269 | u32 gps_gpdat = chip->pm_save[2]; | |
270 | ||
271 | /* First, modify the CON settings */ | |
272 | ||
273 | old_gpcon[0] = 0; | |
274 | old_gpcon[1] = __raw_readl(base + OFFS_CON); | |
275 | ||
782d8a3c | 276 | samsung_gpio_pm_4bit_con(chip, 0); |
d87964c4 BD |
277 | if (chip->chip.ngpio > 8) { |
278 | old_gpcon[0] = __raw_readl(base - 4); | |
782d8a3c | 279 | samsung_gpio_pm_4bit_con(chip, -1); |
d87964c4 BD |
280 | } |
281 | ||
282 | /* Now change the configurations that require DAT,CON */ | |
283 | ||
284 | __raw_writel(chip->pm_save[2], base + OFFS_DAT); | |
285 | __raw_writel(chip->pm_save[1], base + OFFS_CON); | |
286 | if (chip->chip.ngpio > 8) | |
287 | __raw_writel(chip->pm_save[0], base - 4); | |
288 | ||
289 | __raw_writel(chip->pm_save[2], base + OFFS_DAT); | |
290 | __raw_writel(chip->pm_save[3], base + OFFS_UP); | |
291 | ||
292 | if (chip->chip.ngpio > 8) { | |
293 | S3C_PMDBG("%s: CON4 %08x,%08x => %08x,%08x, DAT %08x => %08x\n", | |
294 | chip->chip.label, old_gpcon[0], old_gpcon[1], | |
295 | __raw_readl(base - 4), | |
296 | __raw_readl(base + OFFS_CON), | |
297 | old_gpdat, gps_gpdat); | |
298 | } else | |
299 | S3C_PMDBG("%s: CON4 %08x => %08x, DAT %08x => %08x\n", | |
300 | chip->chip.label, old_gpcon[1], | |
301 | __raw_readl(base + OFFS_CON), | |
302 | old_gpdat, gps_gpdat); | |
303 | } | |
304 | ||
782d8a3c KK |
305 | struct samsung_gpio_pm samsung_gpio_pm_4bit = { |
306 | .save = samsung_gpio_pm_4bit_save, | |
307 | .resume = samsung_gpio_pm_4bit_resume, | |
d87964c4 | 308 | }; |
e9d428ee | 309 | #endif /* CONFIG_ARCH_S3C64XX || CONFIG_PLAT_S5P */ |
d87964c4 BD |
310 | |
311 | /** | |
782d8a3c | 312 | * samsung_pm_save_gpio() - save gpio chip data for suspend |
d87964c4 BD |
313 | * @ourchip: The chip for suspend. |
314 | */ | |
782d8a3c | 315 | static void samsung_pm_save_gpio(struct samsung_gpio_chip *ourchip) |
d87964c4 | 316 | { |
782d8a3c | 317 | struct samsung_gpio_pm *pm = ourchip->pm; |
d87964c4 BD |
318 | |
319 | if (pm == NULL || pm->save == NULL) | |
320 | S3C_PMDBG("%s: no pm for %s\n", __func__, ourchip->chip.label); | |
321 | else | |
322 | pm->save(ourchip); | |
323 | } | |
324 | ||
325 | /** | |
782d8a3c | 326 | * samsung_pm_save_gpios() - Save the state of the GPIO banks. |
d87964c4 BD |
327 | * |
328 | * For all the GPIO banks, save the state of each one ready for going | |
329 | * into a suspend mode. | |
330 | */ | |
782d8a3c | 331 | void samsung_pm_save_gpios(void) |
d87964c4 | 332 | { |
782d8a3c | 333 | struct samsung_gpio_chip *ourchip; |
d87964c4 BD |
334 | unsigned int gpio_nr; |
335 | ||
32b6cb38 | 336 | for (gpio_nr = 0; gpio_nr < S3C_GPIO_END;) { |
782d8a3c | 337 | ourchip = samsung_gpiolib_getchip(gpio_nr); |
91dc74e4 P |
338 | if (!ourchip) { |
339 | gpio_nr++; | |
d87964c4 | 340 | continue; |
91dc74e4 | 341 | } |
d87964c4 | 342 | |
782d8a3c | 343 | samsung_pm_save_gpio(ourchip); |
d87964c4 BD |
344 | |
345 | S3C_PMDBG("%s: save %08x,%08x,%08x,%08x\n", | |
346 | ourchip->chip.label, | |
347 | ourchip->pm_save[0], | |
348 | ourchip->pm_save[1], | |
349 | ourchip->pm_save[2], | |
350 | ourchip->pm_save[3]); | |
351 | ||
352 | gpio_nr += ourchip->chip.ngpio; | |
353 | gpio_nr += CONFIG_S3C_GPIO_SPACE; | |
354 | } | |
355 | } | |
356 | ||
357 | /** | |
782d8a3c | 358 | * samsung_pm_resume_gpio() - restore gpio chip data after suspend |
d87964c4 BD |
359 | * @ourchip: The suspended chip. |
360 | */ | |
782d8a3c | 361 | static void samsung_pm_resume_gpio(struct samsung_gpio_chip *ourchip) |
d87964c4 | 362 | { |
782d8a3c | 363 | struct samsung_gpio_pm *pm = ourchip->pm; |
d87964c4 BD |
364 | |
365 | if (pm == NULL || pm->resume == NULL) | |
366 | S3C_PMDBG("%s: no pm for %s\n", __func__, ourchip->chip.label); | |
367 | else | |
368 | pm->resume(ourchip); | |
369 | } | |
370 | ||
782d8a3c | 371 | void samsung_pm_restore_gpios(void) |
d87964c4 | 372 | { |
782d8a3c | 373 | struct samsung_gpio_chip *ourchip; |
d87964c4 BD |
374 | unsigned int gpio_nr; |
375 | ||
32b6cb38 | 376 | for (gpio_nr = 0; gpio_nr < S3C_GPIO_END;) { |
782d8a3c | 377 | ourchip = samsung_gpiolib_getchip(gpio_nr); |
91dc74e4 P |
378 | if (!ourchip) { |
379 | gpio_nr++; | |
d87964c4 | 380 | continue; |
91dc74e4 | 381 | } |
d87964c4 | 382 | |
782d8a3c | 383 | samsung_pm_resume_gpio(ourchip); |
d87964c4 BD |
384 | |
385 | gpio_nr += ourchip->chip.ngpio; | |
386 | gpio_nr += CONFIG_S3C_GPIO_SPACE; | |
387 | } | |
388 | } |