usb: dwc2: gadget: add mutex to serialize init/deinit calls
This patch adds mutex, which protects initialization and
deinitialization procedures against suspend/resume methods. This mutex
will be needed by the updated suspend/resume calls, which tracks gadget
state.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 2cb0ac3..6b19755 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -576,6 +576,7 @@
struct regulator_bulk_data supplies[ARRAY_SIZE(s3c_hsotg_supply_names)];
spinlock_t lock;
+ struct mutex init_mutex;
void *priv;
int irq;
struct clk *clk;
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 3cd7891..6517334 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -21,6 +21,7 @@
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/debugfs.h>
+#include <linux/mutex.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/io.h>
@@ -2866,6 +2867,7 @@
return -EINVAL;
}
+ mutex_lock(&hsotg->init_mutex);
WARN_ON(hsotg->driver);
driver->driver.bus = NULL;
@@ -2891,9 +2893,12 @@
dev_info(hsotg->dev, "bound driver %s\n", driver->driver.name);
+ mutex_unlock(&hsotg->init_mutex);
+
return 0;
err:
+ mutex_unlock(&hsotg->init_mutex);
hsotg->driver = NULL;
return ret;
}
@@ -2914,6 +2919,8 @@
if (!hsotg)
return -ENODEV;
+ mutex_lock(&hsotg->init_mutex);
+
/* all endpoints should be shutdown */
for (ep = 1; ep < hsotg->num_of_eps; ep++)
s3c_hsotg_ep_disable(&hsotg->eps[ep].ep);
@@ -2931,6 +2938,8 @@
clk_disable(hsotg->clk);
+ mutex_unlock(&hsotg->init_mutex);
+
return 0;
}
@@ -2959,6 +2968,7 @@
dev_dbg(hsotg->dev, "%s: is_on: %d\n", __func__, is_on);
+ mutex_lock(&hsotg->init_mutex);
spin_lock_irqsave(&hsotg->lock, flags);
if (is_on) {
clk_enable(hsotg->clk);
@@ -2970,6 +2980,7 @@
hsotg->gadget.speed = USB_SPEED_UNKNOWN;
spin_unlock_irqrestore(&hsotg->lock, flags);
+ mutex_unlock(&hsotg->init_mutex);
return 0;
}
@@ -3572,6 +3583,8 @@
unsigned long flags;
int ret = 0;
+ mutex_lock(&hsotg->init_mutex);
+
if (hsotg->driver)
dev_info(hsotg->dev, "suspending usb gadget %s\n",
hsotg->driver->driver.name);
@@ -3594,6 +3607,8 @@
clk_disable(hsotg->clk);
}
+ mutex_unlock(&hsotg->init_mutex);
+
return ret;
}
EXPORT_SYMBOL_GPL(s3c_hsotg_suspend);
@@ -3603,6 +3618,8 @@
unsigned long flags;
int ret = 0;
+ mutex_lock(&hsotg->init_mutex);
+
if (hsotg->driver) {
dev_info(hsotg->dev, "resuming usb gadget %s\n",
hsotg->driver->driver.name);
@@ -3619,6 +3636,8 @@
s3c_hsotg_core_connect(hsotg);
spin_unlock_irqrestore(&hsotg->lock, flags);
+ mutex_unlock(&hsotg->init_mutex);
+
return ret;
}
EXPORT_SYMBOL_GPL(s3c_hsotg_resume);
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 57eb8a3..ec5658a 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -40,6 +40,7 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/of_device.h>
+#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/usb/of.h>
@@ -212,6 +213,7 @@
hsotg->dr_mode = of_usb_get_dr_mode(dev->dev.of_node);
spin_lock_init(&hsotg->lock);
+ mutex_init(&hsotg->init_mutex);
retval = dwc2_gadget_init(hsotg, irq);
if (retval)
return retval;