diff options
| -rw-r--r-- | drivers/mmc/core/Makefile | 2 | ||||
| -rw-r--r-- | drivers/mmc/core/cd-gpio.c | 74 | ||||
| -rw-r--r-- | include/linux/mmc/cd-gpio.h | 19 |
3 files changed, 94 insertions, 1 deletions
diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile index 639501970b41..dca4428380f1 100644 --- a/drivers/mmc/core/Makefile +++ b/drivers/mmc/core/Makefile @@ -7,6 +7,6 @@ mmc_core-y := core.o bus.o host.o \ mmc.o mmc_ops.o sd.o sd_ops.o \ sdio.o sdio_ops.o sdio_bus.o \ sdio_cis.o sdio_io.o sdio_irq.o \ - quirks.o + quirks.o cd-gpio.o mmc_core-$(CONFIG_DEBUG_FS) += debugfs.o diff --git a/drivers/mmc/core/cd-gpio.c b/drivers/mmc/core/cd-gpio.c new file mode 100644 index 000000000000..082202ae4a03 --- /dev/null +++ b/drivers/mmc/core/cd-gpio.c @@ -0,0 +1,74 @@ +/* + * Generic GPIO card-detect helper + * + * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/mmc/host.h> +#include <linux/module.h> +#include <linux/slab.h> + +struct mmc_cd_gpio { + unsigned int gpio; + char label[0]; +}; + +static irqreturn_t mmc_cd_gpio_irqt(int irq, void *dev_id) +{ + /* Schedule a card detection after a debounce timeout */ + mmc_detect_change(dev_id, msecs_to_jiffies(100)); + return IRQ_HANDLED; +} + +int mmc_cd_gpio_request(struct mmc_host *host, unsigned int gpio, + unsigned int irq, unsigned long flags) +{ + size_t len = strlen(dev_name(host->parent)) + 4; + struct mmc_cd_gpio *cd = kmalloc(sizeof(*cd) + len, GFP_KERNEL); + int ret; + + if (!cd) + return -ENOMEM; + + snprintf(cd->label, len, "%s cd", dev_name(host->parent)); + + ret = gpio_request_one(gpio, GPIOF_DIR_IN, cd->label); + if (ret < 0) + goto egpioreq; + + ret = request_threaded_irq(irq, NULL, mmc_cd_gpio_irqt, + flags, cd->label, host); + if (ret < 0) + goto eirqreq; + + cd->gpio = gpio; + host->hotplug.irq = irq; + host->hotplug.handler_priv = cd; + + return 0; + +eirqreq: + gpio_free(gpio); +egpioreq: + kfree(cd); + return ret; +} +EXPORT_SYMBOL(mmc_cd_gpio_request); + +void mmc_cd_gpio_free(struct mmc_host *host) +{ + struct mmc_cd_gpio *cd = host->hotplug.handler_priv; + + free_irq(host->hotplug.irq, host); + gpio_free(cd->gpio); + kfree(cd); +} +EXPORT_SYMBOL(mmc_cd_gpio_free); diff --git a/include/linux/mmc/cd-gpio.h b/include/linux/mmc/cd-gpio.h new file mode 100644 index 000000000000..a8e469783318 --- /dev/null +++ b/include/linux/mmc/cd-gpio.h @@ -0,0 +1,19 @@ +/* + * Generic GPIO card-detect helper header + * + * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef MMC_CD_GPIO_H +#define MMC_CD_GPIO_H + +struct mmc_host; +int mmc_cd_gpio_request(struct mmc_host *host, unsigned int gpio, + unsigned int irq, unsigned long flags); +void mmc_cd_gpio_free(struct mmc_host *host); + +#endif |