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// 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);
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