Russell King wrote:
>The allocation function should initialise class_dev as much as possible.
>The registration function should add the class device with the class
>model. The unregistration should remove the class device from the class
>model, but _not_ free it. The free function should drop the last
>reference to the class device, which results in the remove function
>(eventually) being called. Finally, the remove function can free the
>mmc_host.
>
>
New patch according to above system. I've moved the naming a bit earlier
to avoid having a nameless kobj floating around.
>Also note that since we have a class_dev, the mmc_host 'dev' field can
>be removed. However, we'll probably have to update the host drivers
>to do this, so it should be a separate patch.
>
>
>
I believe there's a bit of abstraction to be gained from not poking
around inside the class_dev struct in too many places. It's not like
we're wasting any large amounts of memory.
Rgds
Pierre
Index: linux-wbsd/drivers/mmc/mmc.h
===================================================================
--- linux-wbsd/drivers/mmc/mmc.h (revision 134)
+++ linux-wbsd/drivers/mmc/mmc.h (working copy)
@@ -13,4 +13,7 @@
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);
+void mmc_init_host(struct mmc_host *host);
+int mmc_register_host(struct mmc_host *host);
+void mmc_unregister_host(struct mmc_host *host);
#endif
Index: linux-wbsd/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-wbsd/drivers/mmc/mmc_sysfs.c (revision 153)
+++ linux-wbsd/drivers/mmc/mmc_sysfs.c (working copy)
@@ -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, char *buf) \
@@ -224,14 +225,64 @@
put_device(&card->dev);
}
+static void mmc_host_class_dev_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_class_dev_release,
+};
+
+void mmc_init_host(struct mmc_host *host)
+{
+ static unsigned int host_num;
+
+ snprintf(host->host_name, sizeof(host->host_name),
+ "mmc%d", host_num++);
+
+ host->class_dev.dev = host->dev;
+ host->class_dev.class = &mmc_host_class;
+ strlcpy(host->class_dev.class_id, host->host_name, BUS_ID_SIZE);
+
+ class_device_initialize(&host->class_dev);
+ class_device_get(&host->class_dev);
+}
+
+/*
+ * Internal function. Register a new MMC host with the MMC class.
+ */
+int mmc_register_host(struct mmc_host *host)
+{
+ return class_device_add(&host->class_dev);
+}
+
+/*
+ * Internal function. Unregister a MMC host with the MMC class.
+ */
+void mmc_unregister_host(struct mmc_host *host)
+{
+ class_device_unregister(&host->class_dev);
+}
static int __init mmc_init(void)
{
- return bus_register(&mmc_bus_type);
+ int retval;
+
+ retval = bus_register(&mmc_bus_type);
+ if (retval)
+ return retval;
+ retval = class_register(&mmc_host_class);
+ if (retval)
+ return retval;
+ return 0;
}
static void __exit mmc_exit(void)
{
+ class_unregister(&mmc_host_class);
bus_unregister(&mmc_bus_type);
}
Index: linux-wbsd/drivers/mmc/mmc.c
===================================================================
--- linux-wbsd/drivers/mmc/mmc.c (revision 153)
+++ linux-wbsd/drivers/mmc/mmc.c (working copy)
@@ -1178,6 +1178,8 @@
host->max_phys_segs = 1;
host->max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
host->max_seg_size = PAGE_CACHE_SIZE;
+
+ mmc_init_host(host);
}
return host;
@@ -1191,10 +1193,7 @@
*/
int mmc_add_host(struct mmc_host *host)
{
- static unsigned int host_num;
-
- snprintf(host->host_name, sizeof(host->host_name),
- "mmc%d", host_num++);
+ mmc_register_host(host);
mmc_power_off(host);
mmc_detect_change(host);
@@ -1222,6 +1221,8 @@
}
mmc_power_off(host);
+
+ mmc_unregister_host(host);
}
EXPORT_SYMBOL(mmc_remove_host);
@@ -1235,7 +1236,8 @@
void mmc_free_host(struct mmc_host *host)
{
flush_scheduled_work();
- kfree(host);
+
+ class_device_put(&host->class_dev);
}
EXPORT_SYMBOL(mmc_free_host);
Index: linux-wbsd/include/linux/mmc/host.h
===================================================================
--- linux-wbsd/include/linux/mmc/host.h (revision 153)
+++ linux-wbsd/include/linux/mmc/host.h (working copy)
@@ -69,6 +69,7 @@
struct mmc_host {
struct device *dev;
+ struct class_device class_dev;
struct mmc_host_ops *ops;
unsigned int f_min;
unsigned int f_max;
