Merge tag 'pci-v6.16-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
[linux-2.6-block.git] / drivers / mmc / core / sdio_irq.c
CommitLineData
2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
d1496c39
NP
2/*
3 * linux/drivers/mmc/core/sdio_irq.c
4 *
5 * Author: Nicolas Pitre
6 * Created: June 18, 2007
7 * Copyright: MontaVista Software Inc.
8 *
e633b7bc 9 * Copyright 2008 Pierre Ossman
d1496c39
NP
10 */
11
12#include <linux/kernel.h>
13#include <linux/sched.h>
ae7e81c0 14#include <uapi/linux/sched/types.h>
d1496c39 15#include <linux/kthread.h>
3ef77af1 16#include <linux/export.h>
d1496c39
NP
17#include <linux/wait.h>
18#include <linux/delay.h>
19
20#include <linux/mmc/core.h>
21#include <linux/mmc/host.h>
22#include <linux/mmc/card.h>
23#include <linux/mmc/sdio.h>
24#include <linux/mmc/sdio_func.h>
25
26#include "sdio_ops.h"
55244c56 27#include "core.h"
4facdde1 28#include "card.h"
d1496c39 29
a29b5fcc
MK
30static int sdio_get_pending_irqs(struct mmc_host *host, u8 *pending)
31{
32 struct mmc_card *card = host->card;
33 int ret;
34
35 WARN_ON(!host->claimed);
36
37 ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTx, 0, pending);
38 if (ret) {
39 pr_debug("%s: error %d reading SDIO_CCCR_INTx\n",
40 mmc_card_id(card), ret);
41 return ret;
42 }
43
44 if (*pending && mmc_card_broken_irq_polling(card) &&
45 !(host->caps & MMC_CAP_SDIO_IRQ)) {
46 unsigned char dummy;
47
48 /* A fake interrupt could be created when we poll SDIO_CCCR_INTx
49 * register with a Marvell SD8797 card. A dummy CMD52 read to
50 * function 0 register 0xff can avoid this.
51 */
52 mmc_io_rw_direct(card, 0, 0, 0xff, 0, &dummy);
53 }
54
55 return 0;
56}
57
bbbc4c4d 58static int process_sdio_pending_irqs(struct mmc_host *host)
d1496c39 59{
bbbc4c4d 60 struct mmc_card *card = host->card;
6f4285d1 61 int i, ret, count;
36d57efb 62 bool sdio_irq_pending = host->sdio_irq_pending;
d1496c39 63 unsigned char pending;
06e8935f
SNX
64 struct sdio_func *func;
65
83293386
UH
66 /* Don't process SDIO IRQs if the card is suspended. */
67 if (mmc_card_suspended(card))
68 return 0;
69
36d57efb
UH
70 /* Clear the flag to indicate that we have processed the IRQ. */
71 host->sdio_irq_pending = false;
72
06e8935f
SNX
73 /*
74 * Optimization, if there is only 1 function interrupt registered
bbbc4c4d
NP
75 * and we know an IRQ was signaled then call irq handler directly.
76 * Otherwise do the full probe.
06e8935f
SNX
77 */
78 func = card->sdio_single_irq;
36d57efb 79 if (func && sdio_irq_pending) {
06e8935f
SNX
80 func->irq_handler(func);
81 return 1;
82 }
d1496c39 83
a29b5fcc
MK
84 ret = sdio_get_pending_irqs(host, &pending);
85 if (ret)
d1496c39 86 return ret;
e5624054 87
6f4285d1 88 count = 0;
d1496c39
NP
89 for (i = 1; i <= 7; i++) {
90 if (pending & (1 << i)) {
06e8935f 91 func = card->sdio_func[i - 1];
d1496c39 92 if (!func) {
6606110d 93 pr_warn("%s: pending IRQ for non-existent function\n",
3e01e4bc 94 mmc_card_id(card));
599473cf 95 ret = -EINVAL;
d1496c39
NP
96 } else if (func->irq_handler) {
97 func->irq_handler(func);
6f4285d1 98 count++;
599473cf 99 } else {
6606110d
JP
100 pr_warn("%s: pending IRQ with no handler\n",
101 sdio_func_id(func));
599473cf
NP
102 ret = -EINVAL;
103 }
d1496c39
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104 }
105 }
106
599473cf
NP
107 if (count)
108 return count;
109
110 return ret;
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111}
112
cf4b20ec 113static void sdio_run_irqs(struct mmc_host *host)
bf3b5ec6
RK
114{
115 mmc_claim_host(host);
e3a84267 116 if (host->sdio_irqs) {
e3a84267 117 process_sdio_pending_irqs(host);
51133850
UH
118 if (!host->sdio_irq_pending)
119 host->ops->ack_sdio_irq(host);
e3a84267 120 }
bf3b5ec6
RK
121 mmc_release_host(host);
122}
bf3b5ec6 123
68269660
UH
124void sdio_irq_work(struct work_struct *work)
125{
126 struct mmc_host *host =
1dd611a9 127 container_of(work, struct mmc_host, sdio_irq_work);
68269660
UH
128
129 sdio_run_irqs(host);
130}
131
132void sdio_signal_irq(struct mmc_host *host)
133{
36d57efb 134 host->sdio_irq_pending = true;
1dd611a9 135 schedule_work(&host->sdio_irq_work);
68269660
UH
136}
137EXPORT_SYMBOL_GPL(sdio_signal_irq);
138
d1496c39
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139static int sdio_irq_thread(void *_host)
140{
141 struct mmc_host *host = _host;
6f4285d1 142 unsigned long period, idle_period;
d1496c39
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143 int ret;
144
f8ec806b 145 sched_set_fifo_low(current);
d1496c39
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146
147 /*
148 * We want to allow for SDIO cards to work even on non SDIO
149 * aware hosts. One thing that non SDIO host cannot do is
150 * asynchronous notification of pending SDIO card interrupts
151 * hence we poll for them in that case.
152 */
6f4285d1 153 idle_period = msecs_to_jiffies(10);
17b759af 154 period = (host->caps & MMC_CAP_SDIO_IRQ) ?
6f4285d1 155 MAX_SCHEDULE_TIMEOUT : idle_period;
d1496c39
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156
157 pr_debug("%s: IRQ thread started (poll period = %lu jiffies)\n",
158 mmc_hostname(host), period);
159
160 do {
161 /*
162 * We claim the host here on drivers behalf for a couple
163 * reasons:
164 *
165 * 1) it is already needed to retrieve the CCCR_INTx;
166 * 2) we want the driver(s) to clear the IRQ condition ASAP;
167 * 3) we need to control the abort condition locally.
168 *
169 * Just like traditional hard IRQ handlers, we expect SDIO
170 * IRQ handlers to be quick and to the point, so that the
171 * holding of the host lock does not cover too much work
172 * that doesn't require that lock to be held.
173 */
6c0cedd1
AH
174 ret = __mmc_claim_host(host, NULL,
175 &host->sdio_irq_thread_abort);
d1496c39
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176 if (ret)
177 break;
bbbc4c4d 178 ret = process_sdio_pending_irqs(host);
d1496c39
NP
179 mmc_release_host(host);
180
181 /*
182 * Give other threads a chance to run in the presence of
e633b7bc 183 * errors.
d1496c39 184 */
e633b7bc
PO
185 if (ret < 0) {
186 set_current_state(TASK_INTERRUPTIBLE);
187 if (!kthread_should_stop())
188 schedule_timeout(HZ);
189 set_current_state(TASK_RUNNING);
190 }
d1496c39 191
6f4285d1
PO
192 /*
193 * Adaptive polling frequency based on the assumption
194 * that an interrupt will be closely followed by more.
195 * This has a substantial benefit for network devices.
196 */
197 if (!(host->caps & MMC_CAP_SDIO_IRQ)) {
198 if (ret > 0)
199 period /= 2;
200 else {
201 period++;
202 if (period > idle_period)
203 period = idle_period;
204 }
205 }
206
6fee65cf 207 set_current_state(TASK_INTERRUPTIBLE);
9eadcc05 208 if (host->caps & MMC_CAP_SDIO_IRQ)
17b759af 209 host->ops->enable_sdio_irq(host, 1);
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210 if (!kthread_should_stop())
211 schedule_timeout(period);
6fee65cf 212 set_current_state(TASK_RUNNING);
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213 } while (!kthread_should_stop());
214
9eadcc05 215 if (host->caps & MMC_CAP_SDIO_IRQ)
17b759af
NP
216 host->ops->enable_sdio_irq(host, 0);
217
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NP
218 pr_debug("%s: IRQ thread exiting with code %d\n",
219 mmc_hostname(host), ret);
220
221 return ret;
222}
223
224static int sdio_card_irq_get(struct mmc_card *card)
225{
226 struct mmc_host *host = card->host;
227
d84075c8 228 WARN_ON(!host->claimed);
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229
230 if (!host->sdio_irqs++) {
bf3b5ec6
RK
231 if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD)) {
232 atomic_set(&host->sdio_irq_thread_abort, 0);
233 host->sdio_irq_thread =
234 kthread_run(sdio_irq_thread, host,
235 "ksdioirqd/%s", mmc_hostname(host));
236 if (IS_ERR(host->sdio_irq_thread)) {
237 int err = PTR_ERR(host->sdio_irq_thread);
238 host->sdio_irqs--;
239 return err;
240 }
dea67c4e 241 } else if (host->caps & MMC_CAP_SDIO_IRQ) {
bf3b5ec6 242 host->ops->enable_sdio_irq(host, 1);
d1496c39
NP
243 }
244 }
245
246 return 0;
247}
248
249static int sdio_card_irq_put(struct mmc_card *card)
250{
251 struct mmc_host *host = card->host;
252
d84075c8 253 WARN_ON(!host->claimed);
5df0e823
SL
254
255 if (host->sdio_irqs < 1)
256 return -EINVAL;
d1496c39
NP
257
258 if (!--host->sdio_irqs) {
bf3b5ec6
RK
259 if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD)) {
260 atomic_set(&host->sdio_irq_thread_abort, 1);
261 kthread_stop(host->sdio_irq_thread);
dea67c4e 262 } else if (host->caps & MMC_CAP_SDIO_IRQ) {
bf3b5ec6 263 host->ops->enable_sdio_irq(host, 0);
bf3b5ec6 264 }
d1496c39
NP
265 }
266
267 return 0;
268}
269
06e8935f
SNX
270/* If there is only 1 function registered set sdio_single_irq */
271static void sdio_single_irq_set(struct mmc_card *card)
272{
273 struct sdio_func *func;
274 int i;
275
276 card->sdio_single_irq = NULL;
277 if ((card->host->caps & MMC_CAP_SDIO_IRQ) &&
6660d0ae 278 card->host->sdio_irqs == 1) {
06e8935f 279 for (i = 0; i < card->sdio_funcs; i++) {
6660d0ae
JP
280 func = card->sdio_func[i];
281 if (func && func->irq_handler) {
282 card->sdio_single_irq = func;
283 break;
284 }
285 }
286 }
06e8935f
SNX
287}
288
d1496c39
NP
289/**
290 * sdio_claim_irq - claim the IRQ for a SDIO function
291 * @func: SDIO function
292 * @handler: IRQ handler callback
293 *
294 * Claim and activate the IRQ for the given SDIO function. The provided
295 * handler will be called when that IRQ is asserted. The host is always
8647d26e
JC
296 * claimed already when the handler is called so the handler should not
297 * call sdio_claim_host() or sdio_release_host().
d1496c39
NP
298 */
299int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler)
300{
301 int ret;
302 unsigned char reg;
303
5df0e823
SL
304 if (!func)
305 return -EINVAL;
d1496c39
NP
306
307 pr_debug("SDIO: Enabling IRQ for %s...\n", sdio_func_id(func));
308
309 if (func->irq_handler) {
310 pr_debug("SDIO: IRQ for %s already in use.\n", sdio_func_id(func));
311 return -EBUSY;
312 }
313
314 ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, &reg);
315 if (ret)
316 return ret;
317
318 reg |= 1 << func->num;
319
320 reg |= 1; /* Master interrupt enable */
321
322 ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IENx, reg, NULL);
323 if (ret)
324 return ret;
325
326 func->irq_handler = handler;
327 ret = sdio_card_irq_get(func->card);
328 if (ret)
329 func->irq_handler = NULL;
06e8935f 330 sdio_single_irq_set(func->card);
d1496c39
NP
331
332 return ret;
333}
334EXPORT_SYMBOL_GPL(sdio_claim_irq);
335
336/**
337 * sdio_release_irq - release the IRQ for a SDIO function
338 * @func: SDIO function
339 *
340 * Disable and release the IRQ for the given SDIO function.
341 */
342int sdio_release_irq(struct sdio_func *func)
343{
344 int ret;
345 unsigned char reg;
346
5df0e823
SL
347 if (!func)
348 return -EINVAL;
d1496c39
NP
349
350 pr_debug("SDIO: Disabling IRQ for %s...\n", sdio_func_id(func));
351
352 if (func->irq_handler) {
353 func->irq_handler = NULL;
354 sdio_card_irq_put(func->card);
06e8935f 355 sdio_single_irq_set(func->card);
d1496c39
NP
356 }
357
358 ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, &reg);
359 if (ret)
360 return ret;
361
362 reg &= ~(1 << func->num);
363
364 /* Disable master interrupt with the last function interrupt */
365 if (!(reg & 0xFE))
366 reg = 0;
367
368 ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IENx, reg, NULL);
369 if (ret)
370 return ret;
371
372 return 0;
373}
374EXPORT_SYMBOL_GPL(sdio_release_irq);
375