[PATCH v6 1/2] usb: dwc2: remove no longer needed init_mutex

From: Marek Szyprowski
Date: Wed Oct 14 2015 - 02:52:59 EST


init_mutex is a leftover from the time, when s3c-hsotg driver did not
implement proper pull up/down control and emulated it by enabling
enabling/disabling usb phy. Proper pull up/down control has been added
by commit 5b9451f8c4fbaf0549139755fb45ff2b57975b7f ("usb: dwc2: gadget:
use soft-disconnect udc feature in pullup() method"), so init_muxtex can
be removed now to avoid potential deadlocks with other locks.

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Acked-by: John Youn <johnyoun@xxxxxxxxxxxx>
Tested-by: John Youn <johnyoun@xxxxxxxxxxxx>
---
drivers/usb/dwc2/core.h | 1 -
drivers/usb/dwc2/gadget.c | 17 -----------------
drivers/usb/dwc2/platform.c | 1 -
3 files changed, 19 deletions(-)

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index ebf2504..89091db 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -712,7 +712,6 @@ struct dwc2_hsotg {
struct regulator_bulk_data supplies[ARRAY_SIZE(dwc2_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 7e5670c..79d9f3b 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3193,7 +3193,6 @@ static int dwc2_hsotg_udc_start(struct usb_gadget *gadget,
return -EINVAL;
}

- mutex_lock(&hsotg->init_mutex);
WARN_ON(hsotg->driver);

driver->driver.bus = NULL;
@@ -3220,12 +3219,9 @@ static int dwc2_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;
}
@@ -3246,8 +3242,6 @@ static int dwc2_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++) {
if (hsotg->eps_in[ep])
@@ -3270,8 +3264,6 @@ static int dwc2_hsotg_udc_stop(struct usb_gadget *gadget)

regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies), hsotg->supplies);

- mutex_unlock(&hsotg->init_mutex);
-
return 0;
}

@@ -3307,7 +3299,6 @@ static int dwc2_hsotg_pullup(struct usb_gadget *gadget, int is_on)
return 0;
}

- mutex_lock(&hsotg->init_mutex);
spin_lock_irqsave(&hsotg->lock, flags);
if (is_on) {
hsotg->enabled = 1;
@@ -3321,7 +3312,6 @@ static int dwc2_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;
}
@@ -3832,8 +3822,6 @@ int dwc2_hsotg_suspend(struct dwc2_hsotg *hsotg)
if (hsotg->lx_state != DWC2_L0)
return ret;

- mutex_lock(&hsotg->init_mutex);
-
if (hsotg->driver) {
int ep;

@@ -3861,8 +3849,6 @@ int dwc2_hsotg_suspend(struct dwc2_hsotg *hsotg)
clk_disable(hsotg->clk);
}

- mutex_unlock(&hsotg->init_mutex);
-
return ret;
}

@@ -3874,8 +3860,6 @@ int dwc2_hsotg_resume(struct dwc2_hsotg *hsotg)
if (hsotg->lx_state == DWC2_L2)
return ret;

- mutex_lock(&hsotg->init_mutex);
-
if (hsotg->driver) {
dev_info(hsotg->dev, "resuming usb gadget %s\n",
hsotg->driver->driver.name);
@@ -3892,7 +3876,6 @@ int dwc2_hsotg_resume(struct dwc2_hsotg *hsotg)
dwc2_hsotg_core_connect(hsotg);
spin_unlock_irqrestore(&hsotg->lock, flags);
}
- mutex_unlock(&hsotg->init_mutex);

return ret;
}
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index b920e43..581e9ca 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -252,7 +252,6 @@ static int dwc2_driver_probe(struct platform_device *dev)
}

spin_lock_init(&hsotg->lock);
- mutex_init(&hsotg->init_mutex);

/* Detect config values from hardware */
retval = dwc2_get_hwparams(hsotg);
--
1.9.2

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