Hi,
On Fri, Dec 23 2011, Guennadi Liakhovetski wrote:
> This patch adds a primitive helper to support card hotplug detection on
> platforms, where a GPIO, capable of producing interrupts, is used for
> detection of card-insertion and -removal events.
>
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> ---
> drivers/mmc/core/Makefile | 2 +-
> drivers/mmc/core/cd-gpio.c | 74 +++++++++++++++++++++++++++++++++++++++++++
> include/linux/mmc/cd-gpio.h | 19 +++++++++++
> 3 files changed, 94 insertions(+), 1 deletions(-)
> create mode 100644 drivers/mmc/core/cd-gpio.c
> create mode 100644 include/linux/mmc/cd-gpio.h
>
> diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
> index 6395019..dca4428 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 0000000..4c79f0c
> --- /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@xxxxxx>
> + *
> + * 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;
> +
> + sprintf(cd->label, "%s cd", dev_name(host->parent));
Mind using snprintf() instead? I prefer it for new uses, it leaves
fewer uses of sprintf to audit for correctness.
Thanks,
- Chris.
--
Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
One Laptop Per Child
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
