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-rw-r--r--drivers/mmc/core/host.c2
-rw-r--r--drivers/mmc/core/slot-gpio.c51
-rw-r--r--include/linux/mmc/host.h3
3 files changed, 43 insertions, 13 deletions
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index b8c5290571f..74cf29a504f 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -32,6 +32,7 @@
static void mmc_host_classdev_release(struct device *dev)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
+ mutex_destroy(&host->slot.lock);
kfree(host);
}
@@ -327,6 +328,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
mmc_host_clk_init(host);
+ mutex_init(&host->slot.lock);
host->slot.cd_irq = -EINVAL;
spin_lock_init(&host->lock);
diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
index 92cba02c04b..41689da14b8 100644
--- a/drivers/mmc/core/slot-gpio.c
+++ b/drivers/mmc/core/slot-gpio.c
@@ -29,6 +29,34 @@ static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
return IRQ_HANDLED;
}
+static int mmc_gpio_alloc(struct mmc_host *host)
+{
+ size_t len = strlen(dev_name(host->parent)) + 4;
+ struct mmc_gpio *ctx;
+
+ mutex_lock(&host->slot.lock);
+
+ ctx = host->slot.handler_priv;
+ if (!ctx) {
+ /*
+ * devm_kzalloc() can be called after device_initialize(), even
+ * before device_add(), i.e., between mmc_alloc_host() and
+ * mmc_add_host()
+ */
+ ctx = devm_kzalloc(&host->class_dev, sizeof(*ctx) + len,
+ GFP_KERNEL);
+ if (ctx) {
+ snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent));
+ ctx->cd_gpio = -EINVAL;
+ host->slot.handler_priv = ctx;
+ }
+ }
+
+ mutex_unlock(&host->slot.lock);
+
+ return ctx ? 0 : -ENOMEM;
+}
+
int mmc_gpio_get_cd(struct mmc_host *host)
{
struct mmc_gpio *ctx = host->slot.handler_priv;
@@ -43,20 +71,24 @@ EXPORT_SYMBOL(mmc_gpio_get_cd);
int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
{
- size_t len = strlen(dev_name(host->parent)) + 4;
struct mmc_gpio *ctx;
int irq = gpio_to_irq(gpio);
int ret;
- ctx = kmalloc(sizeof(*ctx) + len, GFP_KERNEL);
- if (!ctx)
- return -ENOMEM;
+ ret = mmc_gpio_alloc(host);
+ if (ret < 0)
+ return ret;
- snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent));
+ ctx = host->slot.handler_priv;
ret = gpio_request_one(gpio, GPIOF_DIR_IN, ctx->cd_label);
if (ret < 0)
- goto egpioreq;
+ /*
+ * don't bother freeing memory. It might still get used by other
+ * slot functions, in any case it will be freed, when the device
+ * is destroyed.
+ */
+ return ret;
/*
* Even if gpio_to_irq() returns a valid IRQ number, the platform might
@@ -80,13 +112,8 @@ int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
host->caps |= MMC_CAP_NEEDS_POLL;
ctx->cd_gpio = gpio;
- host->slot.handler_priv = ctx;
return 0;
-
-egpioreq:
- kfree(ctx);
- return ret;
}
EXPORT_SYMBOL(mmc_gpio_request_cd);
@@ -107,7 +134,5 @@ void mmc_gpio_free_cd(struct mmc_host *host)
ctx->cd_gpio = -EINVAL;
gpio_free(gpio);
- host->slot.handler_priv = NULL;
- kfree(ctx);
}
EXPORT_SYMBOL(mmc_gpio_free_cd);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index c1a03eed1d1..65c64ee578a 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -11,6 +11,7 @@
#define LINUX_MMC_HOST_H
#include <linux/leds.h>
+#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/fault-inject.h>
@@ -154,6 +155,7 @@ struct mmc_async_req {
* struct mmc_slot - MMC slot functions
*
* @cd_irq: MMC/SD-card slot hotplug detection IRQ or -EINVAL
+ * @lock: protect the @handler_priv pointer
* @handler_priv: MMC/SD-card slot context
*
* Some MMC/SD host controllers implement slot-functions like card and
@@ -163,6 +165,7 @@ struct mmc_async_req {
*/
struct mmc_slot {
int cd_irq;
+ struct mutex lock;
void *handler_priv;
};