From: Marek Szyprowski [mailto:m.szyprow...@samsung.com]
Sent: Friday, October 31, 2014 3:13 AM
This patch adds mutex, which protects initialization and
deinitialization procedures against suspend/resume methods.
Signed-off-by: Marek Szyprowski <m.szyprow...@samsung.com>
---
drivers/usb/dwc2/core.h | 1 +
drivers/usb/dwc2/gadget.c | 20 ++++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 9f77b4d1c5ff..58732a9a0019 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -187,6 +187,7 @@ struct s3c_hsotg {
struct s3c_hsotg_plat *plat;
spinlock_t lock;
+ struct mutex init_mutex;
void __iomem *regs;
int irq;
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index d8dda39c9e16..a2e4272a904e 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>
@@ -2908,6 +2909,7 @@ static int s3c_hsotg_udc_start(struct usb_gadget *gadget,
return -EINVAL;
}
+ mutex_lock(&hsotg->init_mutex);
WARN_ON(hsotg->driver);
driver->driver.bus = NULL;
@@ -2933,9 +2935,12 @@ static int s3c_hsotg_udc_start(struct usb_gadget *gadget,
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;
}
@@ -2957,6 +2962,8 @@ static int s3c_hsotg_udc_stop(struct usb_gadget *gadget,
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);
@@ -2974,6 +2981,8 @@ static int s3c_hsotg_udc_stop(struct usb_gadget *gadget,
clk_disable(hsotg->clk);
+ mutex_unlock(&hsotg->init_mutex);
+
return 0;
}
@@ -3002,6 +3011,7 @@ static int s3c_hsotg_pullup(struct usb_gadget *gadget,
int is_on)
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);
@@ -3013,6 +3023,7 @@ static int s3c_hsotg_pullup(struct usb_gadget *gadget,
int is_on)
hsotg->gadget.speed = USB_SPEED_UNKNOWN;
spin_unlock_irqrestore(&hsotg->lock, flags);
+ mutex_unlock(&hsotg->init_mutex);
return 0;
}
@@ -3507,6 +3518,7 @@ static int s3c_hsotg_probe(struct platform_device *pdev)
}
spin_lock_init(&hsotg->lock);
+ mutex_init(&hsotg->init_mutex);
hsotg->irq = ret;
@@ -3652,6 +3664,8 @@ static int s3c_hsotg_suspend(struct platform_device
*pdev, pm_message_t state)
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);
@@ -3674,6 +3688,8 @@ static int s3c_hsotg_suspend(struct platform_device
*pdev, pm_message_t state)
clk_disable(hsotg->clk);
}
+ mutex_unlock(&hsotg->init_mutex);
+
return ret;
}
@@ -3683,7 +3699,9 @@ static int s3c_hsotg_resume(struct platform_device *pdev)
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);
@@ -3699,6 +3717,8 @@ static int s3c_hsotg_resume(struct platform_device *pdev)
s3c_hsotg_core_connect(hsotg);
spin_unlock_irqrestore(&hsotg->lock, flags);
+ mutex_unlock(&hsotg->init_mutex);
+
return ret;
}