Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 366 insertions, 0 deletions

diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
new file mode 100644
index 000000000..d206f2de8
--- /dev/null
+++ b/drivers/mmc/core/sdio_irq.c
@@ -0,0 +1,366 @@
+/*
+ * linux/drivers/mmc/core/sdio_irq.c
+ *
+ * Author:      Nicolas Pitre
+ * Created:     June 18, 2007
+ * Copyright:   MontaVista Software Inc.
+ *
+ * Copyright 2008 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <uapi/linux/sched/types.h>
+#include <linux/kthread.h>
+#include <linux/export.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+
+#include <linux/mmc/core.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/sdio.h>
+#include <linux/mmc/sdio_func.h>
+
+#include "sdio_ops.h"
+#include "core.h"
+#include "card.h"
+
+static int process_sdio_pending_irqs(struct mmc_host *host)
+{
+	struct mmc_card *card = host->card;
+	int i, ret, count;
+	bool sdio_irq_pending = host->sdio_irq_pending;
+	unsigned char pending;
+	struct sdio_func *func;
+
+	/* Don't process SDIO IRQs if the card is suspended. */
+	if (mmc_card_suspended(card))
+		return 0;
+
+	/* Clear the flag to indicate that we have processed the IRQ. */
+	host->sdio_irq_pending = false;
+
+	/*
+	 * Optimization, if there is only 1 function interrupt registered
+	 * and we know an IRQ was signaled then call irq handler directly.
+	 * Otherwise do the full probe.
+	 */
+	func = card->sdio_single_irq;
+	if (func && sdio_irq_pending) {
+		func->irq_handler(func);
+		return 1;
+	}
+
+	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTx, 0, &pending);
+	if (ret) {
+		pr_debug("%s: error %d reading SDIO_CCCR_INTx\n",
+		       mmc_card_id(card), ret);
+		return ret;
+	}
+
+	if (pending && mmc_card_broken_irq_polling(card) &&
+	    !(host->caps & MMC_CAP_SDIO_IRQ)) {
+		unsigned char dummy;
+
+		/* A fake interrupt could be created when we poll SDIO_CCCR_INTx
+		 * register with a Marvell SD8797 card. A dummy CMD52 read to
+		 * function 0 register 0xff can avoid this.
+		 */
+		mmc_io_rw_direct(card, 0, 0, 0xff, 0, &dummy);
+	}
+
+	count = 0;
+	for (i = 1; i <= 7; i++) {
+		if (pending & (1 << i)) {
+			func = card->sdio_func[i - 1];
+			if (!func) {
+				pr_warn("%s: pending IRQ for non-existent function\n",
+					mmc_card_id(card));
+				ret = -EINVAL;
+			} else if (func->irq_handler) {
+				func->irq_handler(func);
+				count++;
+			} else {
+				pr_warn("%s: pending IRQ with no handler\n",
+					sdio_func_id(func));
+				ret = -EINVAL;
+			}
+		}
+	}
+
+	if (count)
+		return count;
+
+	return ret;
+}
+
+void sdio_run_irqs(struct mmc_host *host)
+{
+	mmc_claim_host(host);
+	if (host->sdio_irqs) {
+		process_sdio_pending_irqs(host);
+		if (host->ops->ack_sdio_irq)
+			host->ops->ack_sdio_irq(host);
+	}
+	mmc_release_host(host);
+}
+EXPORT_SYMBOL_GPL(sdio_run_irqs);
+
+void sdio_irq_work(struct work_struct *work)
+{
+	struct mmc_host *host =
+		container_of(work, struct mmc_host, sdio_irq_work.work);
+
+	sdio_run_irqs(host);
+}
+
+void sdio_signal_irq(struct mmc_host *host)
+{
+	host->sdio_irq_pending = true;
+	queue_delayed_work(system_wq, &host->sdio_irq_work, 0);
+}
+EXPORT_SYMBOL_GPL(sdio_signal_irq);
+
+static int sdio_irq_thread(void *_host)
+{
+	struct mmc_host *host = _host;
+	struct sched_param param = { .sched_priority = 1 };
+	unsigned long period, idle_period;
+	int ret;
+
+	sched_setscheduler(current, SCHED_FIFO, &param);
+
+	/*
+	 * We want to allow for SDIO cards to work even on non SDIO
+	 * aware hosts.  One thing that non SDIO host cannot do is
+	 * asynchronous notification of pending SDIO card interrupts
+	 * hence we poll for them in that case.
+	 */
+	idle_period = msecs_to_jiffies(10);
+	period = (host->caps & MMC_CAP_SDIO_IRQ) ?
+		MAX_SCHEDULE_TIMEOUT : idle_period;
+
+	pr_debug("%s: IRQ thread started (poll period = %lu jiffies)\n",
+		 mmc_hostname(host), period);
+
+	do {
+		/*
+		 * We claim the host here on drivers behalf for a couple
+		 * reasons:
+		 *
+		 * 1) it is already needed to retrieve the CCCR_INTx;
+		 * 2) we want the driver(s) to clear the IRQ condition ASAP;
+		 * 3) we need to control the abort condition locally.
+		 *
+		 * Just like traditional hard IRQ handlers, we expect SDIO
+		 * IRQ handlers to be quick and to the point, so that the
+		 * holding of the host lock does not cover too much work
+		 * that doesn't require that lock to be held.
+		 */
+		ret = __mmc_claim_host(host, NULL,
+				       &host->sdio_irq_thread_abort);
+		if (ret)
+			break;
+		ret = process_sdio_pending_irqs(host);
+		mmc_release_host(host);
+
+		/*
+		 * Give other threads a chance to run in the presence of
+		 * errors.
+		 */
+		if (ret < 0) {
+			set_current_state(TASK_INTERRUPTIBLE);
+			if (!kthread_should_stop())
+				schedule_timeout(HZ);
+			set_current_state(TASK_RUNNING);
+		}
+
+		/*
+		 * Adaptive polling frequency based on the assumption
+		 * that an interrupt will be closely followed by more.
+		 * This has a substantial benefit for network devices.
+		 */
+		if (!(host->caps & MMC_CAP_SDIO_IRQ)) {
+			if (ret > 0)
+				period /= 2;
+			else {
+				period++;
+				if (period > idle_period)
+					period = idle_period;
+			}
+		}
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (host->caps & MMC_CAP_SDIO_IRQ)
+			host->ops->enable_sdio_irq(host, 1);
+		if (!kthread_should_stop())
+			schedule_timeout(period);
+		set_current_state(TASK_RUNNING);
+	} while (!kthread_should_stop());
+
+	if (host->caps & MMC_CAP_SDIO_IRQ)
+		host->ops->enable_sdio_irq(host, 0);
+
+	pr_debug("%s: IRQ thread exiting with code %d\n",
+		 mmc_hostname(host), ret);
+
+	return ret;
+}
+
+static int sdio_card_irq_get(struct mmc_card *card)
+{
+	struct mmc_host *host = card->host;
+
+	WARN_ON(!host->claimed);
+
+	if (!host->sdio_irqs++) {
+		if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD)) {
+			atomic_set(&host->sdio_irq_thread_abort, 0);
+			host->sdio_irq_thread =
+				kthread_run(sdio_irq_thread, host,
+					    "ksdioirqd/%s", mmc_hostname(host));
+			if (IS_ERR(host->sdio_irq_thread)) {
+				int err = PTR_ERR(host->sdio_irq_thread);
+				host->sdio_irqs--;
+				return err;
+			}
+		} else if (host->caps & MMC_CAP_SDIO_IRQ) {
+			host->ops->enable_sdio_irq(host, 1);
+		}
+	}
+
+	return 0;
+}
+
+static int sdio_card_irq_put(struct mmc_card *card)
+{
+	struct mmc_host *host = card->host;
+
+	WARN_ON(!host->claimed);
+
+	if (host->sdio_irqs < 1)
+		return -EINVAL;
+
+	if (!--host->sdio_irqs) {
+		if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD)) {
+			atomic_set(&host->sdio_irq_thread_abort, 1);
+			kthread_stop(host->sdio_irq_thread);
+		} else if (host->caps & MMC_CAP_SDIO_IRQ) {
+			host->ops->enable_sdio_irq(host, 0);
+		}
+	}
+
+	return 0;
+}
+
+/* If there is only 1 function registered set sdio_single_irq */
+static void sdio_single_irq_set(struct mmc_card *card)
+{
+	struct sdio_func *func;
+	int i;
+
+	card->sdio_single_irq = NULL;
+	if ((card->host->caps & MMC_CAP_SDIO_IRQ) &&
+	    card->host->sdio_irqs == 1)
+		for (i = 0; i < card->sdio_funcs; i++) {
+		       func = card->sdio_func[i];
+		       if (func && func->irq_handler) {
+			       card->sdio_single_irq = func;
+			       break;
+		       }
+	       }
+}
+
+/**
+ *	sdio_claim_irq - claim the IRQ for a SDIO function
+ *	@func: SDIO function
+ *	@handler: IRQ handler callback
+ *
+ *	Claim and activate the IRQ for the given SDIO function. The provided
+ *	handler will be called when that IRQ is asserted.  The host is always
+ *	claimed already when the handler is called so the handler should not
+ *	call sdio_claim_host() or sdio_release_host().
+ */
+int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler)
+{
+	int ret;
+	unsigned char reg;
+
+	if (!func)
+		return -EINVAL;
+
+	pr_debug("SDIO: Enabling IRQ for %s...\n", sdio_func_id(func));
+
+	if (func->irq_handler) {
+		pr_debug("SDIO: IRQ for %s already in use.\n", sdio_func_id(func));
+		return -EBUSY;
+	}
+
+	ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, &reg);
+	if (ret)
+		return ret;
+
+	reg |= 1 << func->num;
+
+	reg |= 1; /* Master interrupt enable */
+
+	ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IENx, reg, NULL);
+	if (ret)
+		return ret;
+
+	func->irq_handler = handler;
+	ret = sdio_card_irq_get(func->card);
+	if (ret)
+		func->irq_handler = NULL;
+	sdio_single_irq_set(func->card);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sdio_claim_irq);
+
+/**
+ *	sdio_release_irq - release the IRQ for a SDIO function
+ *	@func: SDIO function
+ *
+ *	Disable and release the IRQ for the given SDIO function.
+ */
+int sdio_release_irq(struct sdio_func *func)
+{
+	int ret;
+	unsigned char reg;
+
+	if (!func)
+		return -EINVAL;
+
+	pr_debug("SDIO: Disabling IRQ for %s...\n", sdio_func_id(func));
+
+	if (func->irq_handler) {
+		func->irq_handler = NULL;
+		sdio_card_irq_put(func->card);
+		sdio_single_irq_set(func->card);
+	}
+
+	ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, &reg);
+	if (ret)
+		return ret;
+
+	reg &= ~(1 << func->num);
+
+	/* Disable master interrupt with the last function interrupt */
+	if (!(reg & 0xFE))
+		reg = 0;
+
+	ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IENx, reg, NULL);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sdio_release_irq);
+