1 files changed, 258 insertions, 0 deletions

diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
new file mode 100644
index 000000000..dd2a4b6ab
--- /dev/null
+++ b/drivers/mmc/core/slot-gpio.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generic GPIO card-detect helper
+ *
+ * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ */
+
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/slot-gpio.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "slot-gpio.h"
+
+struct mmc_gpio {
+	struct gpio_desc *ro_gpio;
+	struct gpio_desc *cd_gpio;
+	irqreturn_t (*cd_gpio_isr)(int irq, void *dev_id);
+	char *ro_label;
+	char *cd_label;
+	u32 cd_debounce_delay_ms;
+};
+
+static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
+{
+	/* Schedule a card detection after a debounce timeout */
+	struct mmc_host *host = dev_id;
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	host->trigger_card_event = true;
+	mmc_detect_change(host, msecs_to_jiffies(ctx->cd_debounce_delay_ms));
+
+	return IRQ_HANDLED;
+}
+
+int mmc_gpio_alloc(struct mmc_host *host)
+{
+	const char *devname = dev_name(host->parent);
+	struct mmc_gpio *ctx;
+
+	ctx = devm_kzalloc(host->parent, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->cd_debounce_delay_ms = 200;
+	ctx->cd_label = devm_kasprintf(host->parent, GFP_KERNEL, "%s cd", devname);
+	if (!ctx->cd_label)
+		return -ENOMEM;
+	ctx->ro_label = devm_kasprintf(host->parent, GFP_KERNEL, "%s ro", devname);
+	if (!ctx->ro_label)
+		return -ENOMEM;
+	host->slot.handler_priv = ctx;
+	host->slot.cd_irq = -EINVAL;
+
+	return 0;
+}
+
+int mmc_gpio_get_ro(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	if (!ctx || !ctx->ro_gpio)
+		return -ENOSYS;
+
+	return gpiod_get_value_cansleep(ctx->ro_gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_get_ro);
+
+int mmc_gpio_get_cd(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	int cansleep;
+
+	if (!ctx || !ctx->cd_gpio)
+		return -ENOSYS;
+
+	cansleep = gpiod_cansleep(ctx->cd_gpio);
+	return cansleep ?
+		gpiod_get_value_cansleep(ctx->cd_gpio) :
+		gpiod_get_value(ctx->cd_gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_get_cd);
+
+void mmc_gpiod_request_cd_irq(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	int irq = -EINVAL;
+	int ret;
+
+	if (host->slot.cd_irq >= 0 || !ctx || !ctx->cd_gpio)
+		return;
+
+	/*
+	 * Do not use IRQ if the platform prefers to poll, e.g., because that
+	 * IRQ number is already used by another unit and cannot be shared.
+	 */
+	if (!(host->caps & MMC_CAP_NEEDS_POLL))
+		irq = gpiod_to_irq(ctx->cd_gpio);
+
+	if (irq >= 0) {
+		if (!ctx->cd_gpio_isr)
+			ctx->cd_gpio_isr = mmc_gpio_cd_irqt;
+		ret = devm_request_threaded_irq(host->parent, irq,
+			NULL, ctx->cd_gpio_isr,
+			IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+			ctx->cd_label, host);
+		if (ret < 0)
+			irq = ret;
+	}
+
+	host->slot.cd_irq = irq;
+
+	if (irq < 0)
+		host->caps |= MMC_CAP_NEEDS_POLL;
+}
+EXPORT_SYMBOL(mmc_gpiod_request_cd_irq);
+
+int mmc_gpio_set_cd_wake(struct mmc_host *host, bool on)
+{
+	int ret = 0;
+
+	if (!(host->caps & MMC_CAP_CD_WAKE) ||
+	    host->slot.cd_irq < 0 ||
+	    on == host->slot.cd_wake_enabled)
+		return 0;
+
+	if (on) {
+		ret = enable_irq_wake(host->slot.cd_irq);
+		host->slot.cd_wake_enabled = !ret;
+	} else {
+		disable_irq_wake(host->slot.cd_irq);
+		host->slot.cd_wake_enabled = false;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(mmc_gpio_set_cd_wake);
+
+/* Register an alternate interrupt service routine for
+ * the card-detect GPIO.
+ */
+void mmc_gpio_set_cd_isr(struct mmc_host *host,
+			 irqreturn_t (*isr)(int irq, void *dev_id))
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	WARN_ON(ctx->cd_gpio_isr);
+	ctx->cd_gpio_isr = isr;
+}
+EXPORT_SYMBOL(mmc_gpio_set_cd_isr);
+
+/**
+ * mmc_gpiod_request_cd - request a gpio descriptor for card-detection
+ * @host: mmc host
+ * @con_id: function within the GPIO consumer
+ * @idx: index of the GPIO to obtain in the consumer
+ * @override_active_level: ignore %GPIO_ACTIVE_LOW flag
+ * @debounce: debounce time in microseconds
+ *
+ * Note that this must be called prior to mmc_add_host()
+ * otherwise the caller must also call mmc_gpiod_request_cd_irq().
+ *
+ * Returns zero on success, else an error.
+ */
+int mmc_gpiod_request_cd(struct mmc_host *host, const char *con_id,
+			 unsigned int idx, bool override_active_level,
+			 unsigned int debounce)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	struct gpio_desc *desc;
+	int ret;
+
+	desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	/* Update default label if no con_id provided */
+	if (!con_id)
+		gpiod_set_consumer_name(desc, ctx->cd_label);
+
+	if (debounce) {
+		ret = gpiod_set_debounce(desc, debounce);
+		if (ret < 0)
+			ctx->cd_debounce_delay_ms = debounce / 1000;
+	}
+
+	/* override forces default (active-low) polarity ... */
+	if (override_active_level && !gpiod_is_active_low(desc))
+		gpiod_toggle_active_low(desc);
+
+	/* ... or active-high */
+	if (host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH)
+		gpiod_toggle_active_low(desc);
+
+	ctx->cd_gpio = desc;
+
+	return 0;
+}
+EXPORT_SYMBOL(mmc_gpiod_request_cd);
+
+bool mmc_can_gpio_cd(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	return ctx->cd_gpio ? true : false;
+}
+EXPORT_SYMBOL(mmc_can_gpio_cd);
+
+/**
+ * mmc_gpiod_request_ro - request a gpio descriptor for write protection
+ * @host: mmc host
+ * @con_id: function within the GPIO consumer
+ * @idx: index of the GPIO to obtain in the consumer
+ * @debounce: debounce time in microseconds
+ *
+ * Returns zero on success, else an error.
+ */
+int mmc_gpiod_request_ro(struct mmc_host *host, const char *con_id,
+			 unsigned int idx, unsigned int debounce)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	struct gpio_desc *desc;
+	int ret;
+
+	desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	/* Update default label if no con_id provided */
+	if (!con_id)
+		gpiod_set_consumer_name(desc, ctx->ro_label);
+
+	if (debounce) {
+		ret = gpiod_set_debounce(desc, debounce);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (host->caps2 & MMC_CAP2_RO_ACTIVE_HIGH)
+		gpiod_toggle_active_low(desc);
+
+	ctx->ro_gpio = desc;
+
+	return 0;
+}
+EXPORT_SYMBOL(mmc_gpiod_request_ro);
+
+bool mmc_can_gpio_ro(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	return ctx->ro_gpio ? true : false;
+}
+EXPORT_SYMBOL(mmc_can_gpio_ro);