[MMC] Add MMC class devices
Create a mmc_host class to allow enumeration of MMC host controllers
even though they have no card(s) inserted.
Patch based on work by Pierre Ossman.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index e02e5df..3c59048 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -796,17 +796,13 @@
{
struct mmc_host *host;
- host = kmalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
+ host = mmc_alloc_host_sysfs(extra, dev);
if (host) {
- memset(host, 0, sizeof(struct mmc_host) + extra);
-
spin_lock_init(&host->lock);
init_waitqueue_head(&host->wq);
INIT_LIST_HEAD(&host->cards);
INIT_WORK(&host->detect, mmc_rescan, host);
- host->dev = dev;
-
/*
* By default, hosts do not support SGIO or large requests.
* They have to set these according to their abilities.
@@ -828,15 +824,15 @@
*/
int mmc_add_host(struct mmc_host *host)
{
- static unsigned int host_num;
+ int ret;
- snprintf(host->host_name, sizeof(host->host_name),
- "mmc%d", host_num++);
+ ret = mmc_add_host_sysfs(host);
+ if (ret == 0) {
+ mmc_power_off(host);
+ mmc_detect_change(host);
+ }
- mmc_power_off(host);
- mmc_detect_change(host);
-
- return 0;
+ return ret;
}
EXPORT_SYMBOL(mmc_add_host);
@@ -859,6 +855,7 @@
}
mmc_power_off(host);
+ mmc_remove_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_remove_host);
@@ -872,7 +869,7 @@
void mmc_free_host(struct mmc_host *host)
{
flush_scheduled_work();
- kfree(host);
+ mmc_free_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_free_host);
diff --git a/drivers/mmc/mmc.h b/drivers/mmc/mmc.h
index b498dff..97bae00 100644
--- a/drivers/mmc/mmc.h
+++ b/drivers/mmc/mmc.h
@@ -13,4 +13,9 @@
void mmc_init_card(struct mmc_card *card, struct mmc_host *host);
int mmc_register_card(struct mmc_card *card);
void mmc_remove_card(struct mmc_card *card);
+
+struct mmc_host *mmc_alloc_host_sysfs(int extra, struct device *dev);
+int mmc_add_host_sysfs(struct mmc_host *host);
+void mmc_remove_host_sysfs(struct mmc_host *host);
+void mmc_free_host_sysfs(struct mmc_host *host);
#endif
diff --git a/drivers/mmc/mmc_sysfs.c b/drivers/mmc/mmc_sysfs.c
index 3a6b325..96c1920 100644
--- a/drivers/mmc/mmc_sysfs.c
+++ b/drivers/mmc/mmc_sysfs.c
@@ -20,6 +20,7 @@
#define dev_to_mmc_card(d) container_of(d, struct mmc_card, dev)
#define to_mmc_driver(d) container_of(d, struct mmc_driver, drv)
+#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
#define MMC_ATTR(name, fmt, args...) \
static ssize_t mmc_##name##_show (struct device *dev, struct device_attribute *attr, char *buf) \
@@ -224,13 +225,82 @@
}
+static void mmc_host_classdev_release(struct class_device *dev)
+{
+ struct mmc_host *host = cls_dev_to_mmc_host(dev);
+ kfree(host);
+}
+
+static struct class mmc_host_class = {
+ .name = "mmc_host",
+ .release = mmc_host_classdev_release,
+};
+
+/*
+ * Internal function. Allocate a new MMC host.
+ */
+struct mmc_host *mmc_alloc_host_sysfs(int extra, struct device *dev)
+{
+ struct mmc_host *host;
+
+ host = kmalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
+ if (host) {
+ memset(host, 0, sizeof(struct mmc_host) + extra);
+
+ host->dev = dev;
+ host->class_dev.dev = host->dev;
+ host->class_dev.class = &mmc_host_class;
+ class_device_initialize(&host->class_dev);
+ }
+
+ return host;
+}
+
+/*
+ * Internal function. Register a new MMC host with the MMC class.
+ */
+int mmc_add_host_sysfs(struct mmc_host *host)
+{
+ static unsigned int host_num;
+
+ snprintf(host->host_name, sizeof(host->host_name),
+ "mmc%d", host_num++);
+
+ strlcpy(host->class_dev.class_id, host->host_name, BUS_ID_SIZE);
+ return class_device_add(&host->class_dev);
+}
+
+/*
+ * Internal function. Unregister a MMC host with the MMC class.
+ */
+void mmc_remove_host_sysfs(struct mmc_host *host)
+{
+ class_device_del(&host->class_dev);
+}
+
+/*
+ * Internal function. Free a MMC host.
+ */
+void mmc_free_host_sysfs(struct mmc_host *host)
+{
+ class_device_put(&host->class_dev);
+}
+
+
static int __init mmc_init(void)
{
- return bus_register(&mmc_bus_type);
+ int ret = bus_register(&mmc_bus_type);
+ if (ret == 0) {
+ ret = class_register(&mmc_host_class);
+ if (ret)
+ bus_unregister(&mmc_bus_type);
+ }
+ return ret;
}
static void __exit mmc_exit(void)
{
+ class_unregister(&mmc_host_class);
bus_unregister(&mmc_bus_type);
}