mmc: extend and rename cd-gpio helpers to handle more slot GPIO functions

GPIOs can be used in MMC/SD-card slots not only for hotplug detection, but
also to implement the write-protection pin. Rename cd-gpio helpers to
slot-gpio to make addition of further slot GPIO functions possible.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/slot-gpio.h b/include/linux/mmc/slot-gpio.h
new file mode 100644
index 0000000..edfaa32
--- /dev/null
+++ b/include/linux/mmc/slot-gpio.h
@@ -0,0 +1,18 @@
+/*
+ * 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_SLOT_GPIO_H
+#define MMC_SLOT_GPIO_H
+
+struct mmc_host;
+int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio);
+void mmc_gpio_free_cd(struct mmc_host *host);
+
+#endif