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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Support for the OLPC DCON and OLPC EC access
4 *
5 * Copyright © 2006 Advanced Micro Devices, Inc.
6 * Copyright © 2007-2008 Andres Salomon <dilinger@debian.org>
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/export.h>
12#include <linux/delay.h>
13#include <linux/io.h>
14#include <linux/string.h>
15#include <linux/platform_device.h>
16#include <linux/of.h>
17#include <linux/syscore_ops.h>
18#include <linux/mutex.h>
19#include <linux/olpc-ec.h>
20
21#include <asm/geode.h>
22#include <asm/setup.h>
23#include <asm/olpc.h>
24#include <asm/olpc_ofw.h>
25
26struct olpc_platform_t olpc_platform_info;
27EXPORT_SYMBOL_GPL(olpc_platform_info);
28
29/* what the timeout *should* be (in ms) */
30#define EC_BASE_TIMEOUT 20
31
32/* the timeout that bugs in the EC might force us to actually use */
33static int ec_timeout = EC_BASE_TIMEOUT;
34
35static int __init olpc_ec_timeout_set(char *str)
36{
37 if (get_option(&str, &ec_timeout) != 1) {
38 ec_timeout = EC_BASE_TIMEOUT;
39 printk(KERN_ERR "olpc-ec: invalid argument to "
40 "'olpc_ec_timeout=', ignoring!\n");
41 }
42 printk(KERN_DEBUG "olpc-ec: using %d ms delay for EC commands.\n",
43 ec_timeout);
44 return 1;
45}
46__setup("olpc_ec_timeout=", olpc_ec_timeout_set);
47
48/*
49 * These {i,o}bf_status functions return whether the buffers are full or not.
50 */
51
52static inline unsigned int ibf_status(unsigned int port)
53{
54 return !!(inb(port) & 0x02);
55}
56
57static inline unsigned int obf_status(unsigned int port)
58{
59 return inb(port) & 0x01;
60}
61
62#define wait_on_ibf(p, d) __wait_on_ibf(__LINE__, (p), (d))
63static int __wait_on_ibf(unsigned int line, unsigned int port, int desired)
64{
65 unsigned int timeo;
66 int state = ibf_status(port);
67
68 for (timeo = ec_timeout; state != desired && timeo; timeo--) {
69 mdelay(1);
70 state = ibf_status(port);
71 }
72
73 if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
74 timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
75 printk(KERN_WARNING "olpc-ec: %d: waited %u ms for IBF!\n",
76 line, ec_timeout - timeo);
77 }
78
79 return !(state == desired);
80}
81
82#define wait_on_obf(p, d) __wait_on_obf(__LINE__, (p), (d))
83static int __wait_on_obf(unsigned int line, unsigned int port, int desired)
84{
85 unsigned int timeo;
86 int state = obf_status(port);
87
88 for (timeo = ec_timeout; state != desired && timeo; timeo--) {
89 mdelay(1);
90 state = obf_status(port);
91 }
92
93 if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
94 timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
95 printk(KERN_WARNING "olpc-ec: %d: waited %u ms for OBF!\n",
96 line, ec_timeout - timeo);
97 }
98
99 return !(state == desired);
100}
101
102/*
103 * This allows the kernel to run Embedded Controller commands. The EC is
104 * documented at <http://wiki.laptop.org/go/Embedded_controller>, and the
105 * available EC commands are here:
106 * <http://wiki.laptop.org/go/Ec_specification>. Unfortunately, while
107 * OpenFirmware's source is available, the EC's is not.
108 */
109static int olpc_xo1_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf,
110 size_t outlen, void *arg)
111{
112 int ret = -EIO;
113 int i;
114 int restarts = 0;
115
116 /* Clear OBF */
117 for (i = 0; i < 10 && (obf_status(0x6c) == 1); i++)
118 inb(0x68);
119 if (i == 10) {
120 printk(KERN_ERR "olpc-ec: timeout while attempting to "
121 "clear OBF flag!\n");
122 goto err;
123 }
124
125 if (wait_on_ibf(0x6c, 0)) {
126 printk(KERN_ERR "olpc-ec: timeout waiting for EC to "
127 "quiesce!\n");
128 goto err;
129 }
130
131restart:
132 /*
133 * Note that if we time out during any IBF checks, that's a failure;
134 * we have to return. There's no way for the kernel to clear that.
135 *
136 * If we time out during an OBF check, we can restart the command;
137 * reissuing it will clear the OBF flag, and we should be alright.
138 * The OBF flag will sometimes misbehave due to what we believe
139 * is a hardware quirk..
140 */
141 pr_devel("olpc-ec: running cmd 0x%x\n", cmd);
142 outb(cmd, 0x6c);
143
144 if (wait_on_ibf(0x6c, 0)) {
145 printk(KERN_ERR "olpc-ec: timeout waiting for EC to read "
146 "command!\n");
147 goto err;
148 }
149
150 if (inbuf && inlen) {
151 /* write data to EC */
152 for (i = 0; i < inlen; i++) {
153 pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]);
154 outb(inbuf[i], 0x68);
155 if (wait_on_ibf(0x6c, 0)) {
156 printk(KERN_ERR "olpc-ec: timeout waiting for"
157 " EC accept data!\n");
158 goto err;
159 }
160 }
161 }
162 if (outbuf && outlen) {
163 /* read data from EC */
164 for (i = 0; i < outlen; i++) {
165 if (wait_on_obf(0x6c, 1)) {
166 printk(KERN_ERR "olpc-ec: timeout waiting for"
167 " EC to provide data!\n");
168 if (restarts++ < 10)
169 goto restart;
170 goto err;
171 }
172 outbuf[i] = inb(0x68);
173 pr_devel("olpc-ec: received 0x%x\n", outbuf[i]);
174 }
175 }
176
177 ret = 0;
178err:
179 return ret;
180}
181
182static bool __init check_ofw_architecture(struct device_node *root)
183{
184 const char *olpc_arch;
185 int propsize;
186
187 olpc_arch = of_get_property(root, "architecture", &propsize);
188 return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
189}
190
191static u32 __init get_board_revision(struct device_node *root)
192{
193 int propsize;
194 const __be32 *rev;
195
196 rev = of_get_property(root, "board-revision-int", &propsize);
197 if (propsize != 4)
198 return 0;
199
200 return be32_to_cpu(*rev);
201}
202
203static bool __init platform_detect(void)
204{
205 struct device_node *root = of_find_node_by_path("/");
206 bool success;
207
208 if (!root)
209 return false;
210
211 success = check_ofw_architecture(root);
212 if (success) {
213 olpc_platform_info.boardrev = get_board_revision(root);
214 olpc_platform_info.flags |= OLPC_F_PRESENT;
215
216 pr_info("OLPC board revision %s%X\n",
217 ((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
218 olpc_platform_info.boardrev >> 4);
219 }
220
221 of_node_put(root);
222 return success;
223}
224
225static int __init add_xo1_platform_devices(void)
226{
227 struct platform_device *pdev;
228
229 pdev = platform_device_register_simple("xo1-rfkill", -1, NULL, 0);
230 if (IS_ERR(pdev))
231 return PTR_ERR(pdev);
232
233 pdev = platform_device_register_simple("olpc-xo1", -1, NULL, 0);
234
235 return PTR_ERR_OR_ZERO(pdev);
236}
237
238static int olpc_xo1_ec_suspend(struct platform_device *pdev)
239{
240 /*
241 * Squelch SCIs while suspended. This is a fix for
242 * <http://dev.laptop.org/ticket/1835>.
243 */
244 return olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0);
245}
246
247static int olpc_xo1_ec_resume(struct platform_device *pdev)
248{
249 /* Tell the EC to stop inhibiting SCIs */
250 olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0);
251
252 /*
253 * Tell the wireless module to restart USB communication.
254 * Must be done twice.
255 */
256 olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
257 olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
258
259 return 0;
260}
261
262static struct olpc_ec_driver ec_xo1_driver = {
263 .suspend = olpc_xo1_ec_suspend,
264 .resume = olpc_xo1_ec_resume,
265 .ec_cmd = olpc_xo1_ec_cmd,
266#ifdef CONFIG_OLPC_XO1_SCI
267 /*
268 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
269 * compiled in
270 */
271 .wakeup_available = true,
272#endif
273};
274
275static struct olpc_ec_driver ec_xo1_5_driver = {
276 .ec_cmd = olpc_xo1_ec_cmd,
277#ifdef CONFIG_OLPC_XO15_SCI
278 /*
279 * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
280 * compiled in
281 */
282 .wakeup_available = true,
283#endif
284};
285
286static int __init olpc_init(void)
287{
288 int r = 0;
289
290 if (!olpc_ofw_present() || !platform_detect())
291 return 0;
292
293 /* register the XO-1 and 1.5-specific EC handler */
294 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
295 olpc_ec_driver_register(&ec_xo1_driver, NULL);
296 else
297 olpc_ec_driver_register(&ec_xo1_5_driver, NULL);
298 platform_device_register_simple("olpc-ec", -1, NULL, 0);
299
300 /* assume B1 and above models always have a DCON */
301 if (olpc_board_at_least(olpc_board(0xb1)))
302 olpc_platform_info.flags |= OLPC_F_DCON;
303
304#ifdef CONFIG_PCI_OLPC
305 /* If the VSA exists let it emulate PCI, if not emulate in kernel.
306 * XO-1 only. */
307 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0) &&
308 !cs5535_has_vsa2())
309 x86_init.pci.arch_init = pci_olpc_init;
310#endif
311
312 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
313 r = add_xo1_platform_devices();
314 if (r)
315 return r;
316 }
317
318 return 0;
319}
320
321postcore_initcall(olpc_init);
1/*
2 * Support for the OLPC DCON and OLPC EC access
3 *
4 * Copyright © 2006 Advanced Micro Devices, Inc.
5 * Copyright © 2007-2008 Andres Salomon <dilinger@debian.org>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/delay.h>
17#include <linux/spinlock.h>
18#include <linux/io.h>
19#include <linux/string.h>
20#include <linux/platform_device.h>
21#include <linux/of.h>
22#include <linux/syscore_ops.h>
23
24#include <asm/geode.h>
25#include <asm/setup.h>
26#include <asm/olpc.h>
27#include <asm/olpc_ofw.h>
28
29struct olpc_platform_t olpc_platform_info;
30EXPORT_SYMBOL_GPL(olpc_platform_info);
31
32static DEFINE_SPINLOCK(ec_lock);
33
34/* EC event mask to be applied during suspend (defining wakeup sources). */
35static u16 ec_wakeup_mask;
36
37/* what the timeout *should* be (in ms) */
38#define EC_BASE_TIMEOUT 20
39
40/* the timeout that bugs in the EC might force us to actually use */
41static int ec_timeout = EC_BASE_TIMEOUT;
42
43static int __init olpc_ec_timeout_set(char *str)
44{
45 if (get_option(&str, &ec_timeout) != 1) {
46 ec_timeout = EC_BASE_TIMEOUT;
47 printk(KERN_ERR "olpc-ec: invalid argument to "
48 "'olpc_ec_timeout=', ignoring!\n");
49 }
50 printk(KERN_DEBUG "olpc-ec: using %d ms delay for EC commands.\n",
51 ec_timeout);
52 return 1;
53}
54__setup("olpc_ec_timeout=", olpc_ec_timeout_set);
55
56/*
57 * These {i,o}bf_status functions return whether the buffers are full or not.
58 */
59
60static inline unsigned int ibf_status(unsigned int port)
61{
62 return !!(inb(port) & 0x02);
63}
64
65static inline unsigned int obf_status(unsigned int port)
66{
67 return inb(port) & 0x01;
68}
69
70#define wait_on_ibf(p, d) __wait_on_ibf(__LINE__, (p), (d))
71static int __wait_on_ibf(unsigned int line, unsigned int port, int desired)
72{
73 unsigned int timeo;
74 int state = ibf_status(port);
75
76 for (timeo = ec_timeout; state != desired && timeo; timeo--) {
77 mdelay(1);
78 state = ibf_status(port);
79 }
80
81 if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
82 timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
83 printk(KERN_WARNING "olpc-ec: %d: waited %u ms for IBF!\n",
84 line, ec_timeout - timeo);
85 }
86
87 return !(state == desired);
88}
89
90#define wait_on_obf(p, d) __wait_on_obf(__LINE__, (p), (d))
91static int __wait_on_obf(unsigned int line, unsigned int port, int desired)
92{
93 unsigned int timeo;
94 int state = obf_status(port);
95
96 for (timeo = ec_timeout; state != desired && timeo; timeo--) {
97 mdelay(1);
98 state = obf_status(port);
99 }
100
101 if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
102 timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
103 printk(KERN_WARNING "olpc-ec: %d: waited %u ms for OBF!\n",
104 line, ec_timeout - timeo);
105 }
106
107 return !(state == desired);
108}
109
110/*
111 * This allows the kernel to run Embedded Controller commands. The EC is
112 * documented at <http://wiki.laptop.org/go/Embedded_controller>, and the
113 * available EC commands are here:
114 * <http://wiki.laptop.org/go/Ec_specification>. Unfortunately, while
115 * OpenFirmware's source is available, the EC's is not.
116 */
117int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
118 unsigned char *outbuf, size_t outlen)
119{
120 unsigned long flags;
121 int ret = -EIO;
122 int i;
123 int restarts = 0;
124
125 spin_lock_irqsave(&ec_lock, flags);
126
127 /* Clear OBF */
128 for (i = 0; i < 10 && (obf_status(0x6c) == 1); i++)
129 inb(0x68);
130 if (i == 10) {
131 printk(KERN_ERR "olpc-ec: timeout while attempting to "
132 "clear OBF flag!\n");
133 goto err;
134 }
135
136 if (wait_on_ibf(0x6c, 0)) {
137 printk(KERN_ERR "olpc-ec: timeout waiting for EC to "
138 "quiesce!\n");
139 goto err;
140 }
141
142restart:
143 /*
144 * Note that if we time out during any IBF checks, that's a failure;
145 * we have to return. There's no way for the kernel to clear that.
146 *
147 * If we time out during an OBF check, we can restart the command;
148 * reissuing it will clear the OBF flag, and we should be alright.
149 * The OBF flag will sometimes misbehave due to what we believe
150 * is a hardware quirk..
151 */
152 pr_devel("olpc-ec: running cmd 0x%x\n", cmd);
153 outb(cmd, 0x6c);
154
155 if (wait_on_ibf(0x6c, 0)) {
156 printk(KERN_ERR "olpc-ec: timeout waiting for EC to read "
157 "command!\n");
158 goto err;
159 }
160
161 if (inbuf && inlen) {
162 /* write data to EC */
163 for (i = 0; i < inlen; i++) {
164 pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]);
165 outb(inbuf[i], 0x68);
166 if (wait_on_ibf(0x6c, 0)) {
167 printk(KERN_ERR "olpc-ec: timeout waiting for"
168 " EC accept data!\n");
169 goto err;
170 }
171 }
172 }
173 if (outbuf && outlen) {
174 /* read data from EC */
175 for (i = 0; i < outlen; i++) {
176 if (wait_on_obf(0x6c, 1)) {
177 printk(KERN_ERR "olpc-ec: timeout waiting for"
178 " EC to provide data!\n");
179 if (restarts++ < 10)
180 goto restart;
181 goto err;
182 }
183 outbuf[i] = inb(0x68);
184 pr_devel("olpc-ec: received 0x%x\n", outbuf[i]);
185 }
186 }
187
188 ret = 0;
189err:
190 spin_unlock_irqrestore(&ec_lock, flags);
191 return ret;
192}
193EXPORT_SYMBOL_GPL(olpc_ec_cmd);
194
195void olpc_ec_wakeup_set(u16 value)
196{
197 ec_wakeup_mask |= value;
198}
199EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);
200
201void olpc_ec_wakeup_clear(u16 value)
202{
203 ec_wakeup_mask &= ~value;
204}
205EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);
206
207/*
208 * Returns true if the compile and runtime configurations allow for EC events
209 * to wake the system.
210 */
211bool olpc_ec_wakeup_available(void)
212{
213 if (!machine_is_olpc())
214 return false;
215
216 /*
217 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
218 * compiled in
219 */
220#ifdef CONFIG_OLPC_XO1_SCI
221 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
222 return true;
223#endif
224
225 /*
226 * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
227 * compiled in
228 */
229#ifdef CONFIG_OLPC_XO15_SCI
230 if (olpc_platform_info.boardrev >= olpc_board_pre(0xd0)) /* XO-1.5 */
231 return true;
232#endif
233
234 return false;
235}
236EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
237
238int olpc_ec_mask_write(u16 bits)
239{
240 if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
241 __be16 ec_word = cpu_to_be16(bits);
242 return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2,
243 NULL, 0);
244 } else {
245 unsigned char ec_byte = bits & 0xff;
246 return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
247 }
248}
249EXPORT_SYMBOL_GPL(olpc_ec_mask_write);
250
251int olpc_ec_sci_query(u16 *sci_value)
252{
253 int ret;
254
255 if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
256 __be16 ec_word;
257 ret = olpc_ec_cmd(EC_EXT_SCI_QUERY,
258 NULL, 0, (void *) &ec_word, 2);
259 if (ret == 0)
260 *sci_value = be16_to_cpu(ec_word);
261 } else {
262 unsigned char ec_byte;
263 ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
264 if (ret == 0)
265 *sci_value = ec_byte;
266 }
267
268 return ret;
269}
270EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
271
272static int olpc_ec_suspend(void)
273{
274 return olpc_ec_mask_write(ec_wakeup_mask);
275}
276
277static bool __init check_ofw_architecture(struct device_node *root)
278{
279 const char *olpc_arch;
280 int propsize;
281
282 olpc_arch = of_get_property(root, "architecture", &propsize);
283 return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
284}
285
286static u32 __init get_board_revision(struct device_node *root)
287{
288 int propsize;
289 const __be32 *rev;
290
291 rev = of_get_property(root, "board-revision-int", &propsize);
292 if (propsize != 4)
293 return 0;
294
295 return be32_to_cpu(*rev);
296}
297
298static bool __init platform_detect(void)
299{
300 struct device_node *root = of_find_node_by_path("/");
301 bool success;
302
303 if (!root)
304 return false;
305
306 success = check_ofw_architecture(root);
307 if (success) {
308 olpc_platform_info.boardrev = get_board_revision(root);
309 olpc_platform_info.flags |= OLPC_F_PRESENT;
310 }
311
312 of_node_put(root);
313 return success;
314}
315
316static int __init add_xo1_platform_devices(void)
317{
318 struct platform_device *pdev;
319
320 pdev = platform_device_register_simple("xo1-rfkill", -1, NULL, 0);
321 if (IS_ERR(pdev))
322 return PTR_ERR(pdev);
323
324 pdev = platform_device_register_simple("olpc-xo1", -1, NULL, 0);
325 if (IS_ERR(pdev))
326 return PTR_ERR(pdev);
327
328 return 0;
329}
330
331static struct syscore_ops olpc_syscore_ops = {
332 .suspend = olpc_ec_suspend,
333};
334
335static int __init olpc_init(void)
336{
337 int r = 0;
338
339 if (!olpc_ofw_present() || !platform_detect())
340 return 0;
341
342 spin_lock_init(&ec_lock);
343
344 /* assume B1 and above models always have a DCON */
345 if (olpc_board_at_least(olpc_board(0xb1)))
346 olpc_platform_info.flags |= OLPC_F_DCON;
347
348 /* get the EC revision */
349 olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0,
350 (unsigned char *) &olpc_platform_info.ecver, 1);
351
352#ifdef CONFIG_PCI_OLPC
353 /* If the VSA exists let it emulate PCI, if not emulate in kernel.
354 * XO-1 only. */
355 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0) &&
356 !cs5535_has_vsa2())
357 x86_init.pci.arch_init = pci_olpc_init;
358#endif
359 /* EC version 0x5f adds support for wide SCI mask */
360 if (olpc_platform_info.ecver >= 0x5f)
361 olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI;
362
363 printk(KERN_INFO "OLPC board revision %s%X (EC=%x)\n",
364 ((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
365 olpc_platform_info.boardrev >> 4,
366 olpc_platform_info.ecver);
367
368 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
369 r = add_xo1_platform_devices();
370 if (r)
371 return r;
372 }
373
374 register_syscore_ops(&olpc_syscore_ops);
375
376 return 0;
377}
378
379postcore_initcall(olpc_init);