2 * Generic GPIO card-detect helper
4 * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/err.h>
12 #include <linux/gpio.h>
13 #include <linux/interrupt.h>
14 #include <linux/jiffies.h>
15 #include <linux/mmc/host.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
24 static irqreturn_t mmc_cd_gpio_irqt(int irq, void *dev_id)
26 /* Schedule a card detection after a debounce timeout */
27 mmc_detect_change(dev_id, msecs_to_jiffies(100));
31 int mmc_cd_gpio_request(struct mmc_host *host, unsigned int gpio,
32 unsigned int irq, unsigned long flags)
34 size_t len = strlen(dev_name(host->parent)) + 4;
35 struct mmc_cd_gpio *cd = kmalloc(sizeof(*cd) + len, GFP_KERNEL);
41 snprintf(cd->label, len, "%s cd", dev_name(host->parent));
43 ret = gpio_request_one(gpio, GPIOF_DIR_IN, cd->label);
47 ret = request_threaded_irq(irq, NULL, mmc_cd_gpio_irqt,
48 flags, cd->label, host);
53 host->hotplug.irq = irq;
54 host->hotplug.handler_priv = cd;
64 EXPORT_SYMBOL(mmc_cd_gpio_request);
66 void mmc_cd_gpio_free(struct mmc_host *host)
68 struct mmc_cd_gpio *cd = host->hotplug.handler_priv;
70 free_irq(host->hotplug.irq, host);
74 EXPORT_SYMBOL(mmc_cd_gpio_free);