diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index c89103786b1cba8d7d607bb8228b47ce6e00e7ff..a00420e9626b65fd4670bedd2e7b7b79f86a8073 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -52,6 +52,8 @@
* between each attampt. When the busy bit is still set at that time,
* the access attempt is considered to have failed,
* and we will print an error.
+ * If the usb_cache_mutex is already held then the _lock variants must
+ * be used instead.
*/
static inline void rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
const unsigned int offset,
@@ -64,6 +66,17 @@ static inline void rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
*value = le16_to_cpu(reg);
}
+static inline void rt2500usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset,
+ u16 *value)
+{
+ __le16 reg;
+ rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
+ USB_VENDOR_REQUEST_IN, offset,
+ ®, sizeof(u16), REGISTER_TIMEOUT);
+ *value = le16_to_cpu(reg);
+}
+
static inline void rt2500usb_register_multiread(struct rt2x00_dev *rt2x00dev,
const unsigned int offset,
void *value, const u16 length)
@@ -84,6 +97,16 @@ static inline void rt2500usb_register_write(struct rt2x00_dev *rt2x00dev,
®, sizeof(u16), REGISTER_TIMEOUT);
}
+static inline void rt2500usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset,
+ u16 value)
+{
+ __le16 reg = cpu_to_le16(value);
+ rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_WRITE,
+ USB_VENDOR_REQUEST_OUT, offset,
+ ®, sizeof(u16), REGISTER_TIMEOUT);
+}
+
static inline void rt2500usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
const unsigned int offset,
void *value, const u16 length)
@@ -100,7 +123,7 @@ static u16 rt2500usb_bbp_check(struct rt2x00_dev *rt2x00dev)
unsigned int i;
for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
- rt2500usb_register_read(rt2x00dev, PHY_CSR8, ®);
+ rt2500usb_register_read_lock(rt2x00dev, PHY_CSR8, ®);
if (!rt2x00_get_field16(reg, PHY_CSR8_BUSY))
break;
udelay(REGISTER_BUSY_DELAY);
@@ -114,12 +137,15 @@ static void rt2500usb_bbp_write(struct rt2x00_dev *rt2x00dev,
{
u16 reg;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
/*
* Wait until the BBP becomes ready.
*/
reg = rt2500usb_bbp_check(rt2x00dev);
if (rt2x00_get_field16(reg, PHY_CSR8_BUSY)) {
ERROR(rt2x00dev, "PHY_CSR8 register busy. Write failed.\n");
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
return;
}
@@ -131,7 +157,9 @@ static void rt2500usb_bbp_write(struct rt2x00_dev *rt2x00dev,
rt2x00_set_field16(®, PHY_CSR7_REG_ID, word);
rt2x00_set_field16(®, PHY_CSR7_READ_CONTROL, 0);
- rt2500usb_register_write(rt2x00dev, PHY_CSR7, reg);
+ rt2500usb_register_write_lock(rt2x00dev, PHY_CSR7, reg);
+
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
static void rt2500usb_bbp_read(struct rt2x00_dev *rt2x00dev,
@@ -139,6 +167,8 @@ static void rt2500usb_bbp_read(struct rt2x00_dev *rt2x00dev,
{
u16 reg;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
/*
* Wait until the BBP becomes ready.
*/
@@ -155,7 +185,7 @@ static void rt2500usb_bbp_read(struct rt2x00_dev *rt2x00dev,
rt2x00_set_field16(®, PHY_CSR7_REG_ID, word);
rt2x00_set_field16(®, PHY_CSR7_READ_CONTROL, 1);
- rt2500usb_register_write(rt2x00dev, PHY_CSR7, reg);
+ rt2500usb_register_write_lock(rt2x00dev, PHY_CSR7, reg);
/*
* Wait until the BBP becomes ready.
@@ -164,11 +194,14 @@ static void rt2500usb_bbp_read(struct rt2x00_dev *rt2x00dev,
if (rt2x00_get_field16(reg, PHY_CSR8_BUSY)) {
ERROR(rt2x00dev, "PHY_CSR8 register busy. Read failed.\n");
*value = 0xff;
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
return;
}
- rt2500usb_register_read(rt2x00dev, PHY_CSR7, ®);
+ rt2500usb_register_read_lock(rt2x00dev, PHY_CSR7, ®);
*value = rt2x00_get_field16(reg, PHY_CSR7_DATA);
+
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
static void rt2500usb_rf_write(struct rt2x00_dev *rt2x00dev,
@@ -180,20 +213,23 @@ static void rt2500usb_rf_write(struct rt2x00_dev *rt2x00dev,
if (!word)
return;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
- rt2500usb_register_read(rt2x00dev, PHY_CSR10, ®);
+ rt2500usb_register_read_lock(rt2x00dev, PHY_CSR10, ®);
if (!rt2x00_get_field16(reg, PHY_CSR10_RF_BUSY))
goto rf_write;
udelay(REGISTER_BUSY_DELAY);
}
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
ERROR(rt2x00dev, "PHY_CSR10 register busy. Write failed.\n");
return;
rf_write:
reg = 0;
rt2x00_set_field16(®, PHY_CSR9_RF_VALUE, value);
- rt2500usb_register_write(rt2x00dev, PHY_CSR9, reg);
+ rt2500usb_register_write_lock(rt2x00dev, PHY_CSR9, reg);
reg = 0;
rt2x00_set_field16(®, PHY_CSR10_RF_VALUE, value >> 16);
@@ -201,8 +237,10 @@ rf_write:
rt2x00_set_field16(®, PHY_CSR10_RF_IF_SELECT, 0);
rt2x00_set_field16(®, PHY_CSR10_RF_BUSY, 1);
- rt2500usb_register_write(rt2x00dev, PHY_CSR10, reg);
+ rt2500usb_register_write_lock(rt2x00dev, PHY_CSR10, reg);
rt2x00_rf_write(rt2x00dev, word, value);
+
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 2cd2c9fab1a59915a3d928ea9a80af04c923a67d..75c9a766e4211530edf722ca5b222118bb2f6b6b 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -31,6 +31,7 @@
#include <linux/skbuff.h>
#include <linux/workqueue.h>
#include <linux/firmware.h>
+#include <linux/mutex.h>
#include <net/mac80211.h>
@@ -658,6 +659,18 @@ struct rt2x00_dev {
void __iomem *csr_addr;
void *csr_cache;
+ /*
+ * Mutex to protect register accesses on USB devices.
+ * There are 2 reasons this is needed, one is to ensure
+ * use of the csr_cache (for USB devices) by one thread
+ * isn't corrupted by another thread trying to access it.
+ * The other is that access to BBP and RF registers
+ * require multiple BUS transactions and if another thread
+ * attempted to access one of those registers at the same
+ * time one of the writes could silently fail.
+ */
+ struct mutex usb_cache_mutex;
+
/*
* Interface configuration.
*/
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index ab97b0600ec8b3ecd07ef07392b6d38189fe7885..a8f0f80ddd216732864a7d0779e70b41ffa61ffc 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -31,6 +31,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>
+#include <linux/bug.h>
#include "rt2x00.h"
#include "rt2x00usb.h"
@@ -52,6 +53,7 @@ int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
(requesttype == USB_VENDOR_REQUEST_IN) ?
usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
+
for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
status = usb_control_msg(usb_dev, pipe, request, requesttype,
value, offset, buffer, buffer_length,
@@ -76,13 +78,15 @@ int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
}
EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
-int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
- const u8 request, const u8 requesttype,
- const u16 offset, void *buffer,
- const u16 buffer_length, const int timeout)
+int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
+ const u8 request, const u8 requesttype,
+ const u16 offset, void *buffer,
+ const u16 buffer_length, const int timeout)
{
int status;
+ BUG_ON(!mutex_is_locked(&rt2x00dev->usb_cache_mutex));
+
/*
* Check for Cache availability.
*/
@@ -103,6 +107,25 @@ int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
return status;
}
+EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
+
+int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
+ const u8 request, const u8 requesttype,
+ const u16 offset, void *buffer,
+ const u16 buffer_length, const int timeout)
+{
+ int status;
+
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
+ status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
+ requesttype, offset, buffer,
+ buffer_length, timeout);
+
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
+
+ return status;
+}
EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
/*
@@ -507,6 +530,7 @@ int rt2x00usb_probe(struct usb_interface *usb_intf,
rt2x00dev->dev = usb_intf;
rt2x00dev->ops = ops;
rt2x00dev->hw = hw;
+ mutex_init(&rt2x00dev->usb_cache_mutex);
rt2x00dev->usb_maxpacket =
usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.h b/drivers/net/wireless/rt2x00/rt2x00usb.h
index 53282b0369272a5320f167831406d02ed6bb6ec7..2fa45c57a73fa812f050a6bc2df21b47aea92dc9 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.h
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.h
@@ -112,6 +112,14 @@ int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
const u16 offset, void *buffer,
const u16 buffer_length, const int timeout);
+/*
+ * A version of rt2x00usb_vendor_request_buff which must be called
+ * if the usb_cache_mutex is already held. */
+int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
+ const u8 request, const u8 requesttype,
+ const u16 offset, void *buffer,
+ const u16 buffer_length, const int timeout);
+
/*
* Simple wrapper around rt2x00usb_vendor_request to write a single
* command to the device. Since we don't use the buffer argument we
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index d89db266757c6c466877061f3dbe4193041ad642..7caa3639dadf3d495ca63df1f49d2ffab3b91dae 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -52,6 +52,7 @@
* between each attampt. When the busy bit is still set at that time,
* the access attempt is considered to have failed,
* and we will print an error.
+ * The _lock versions must be used if you already hold the usb_cache_mutex
*/
static inline void rt73usb_register_read(struct rt2x00_dev *rt2x00dev,
const unsigned int offset, u32 *value)
@@ -63,6 +64,16 @@ static inline void rt73usb_register_read(struct rt2x00_dev *rt2x00dev,
*value = le32_to_cpu(reg);
}
+static inline void rt73usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset, u32 *value)
+{
+ __le32 reg;
+ rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
+ USB_VENDOR_REQUEST_IN, offset,
+ ®, sizeof(u32), REGISTER_TIMEOUT);
+ *value = le32_to_cpu(reg);
+}
+
static inline void rt73usb_register_multiread(struct rt2x00_dev *rt2x00dev,
const unsigned int offset,
void *value, const u32 length)
@@ -82,6 +93,15 @@ static inline void rt73usb_register_write(struct rt2x00_dev *rt2x00dev,
®, sizeof(u32), REGISTER_TIMEOUT);
}
+static inline void rt73usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset, u32 value)
+{
+ __le32 reg = cpu_to_le32(value);
+ rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_WRITE,
+ USB_VENDOR_REQUEST_OUT, offset,
+ ®, sizeof(u32), REGISTER_TIMEOUT);
+}
+
static inline void rt73usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
const unsigned int offset,
void *value, const u32 length)
@@ -98,7 +118,7 @@ static u32 rt73usb_bbp_check(struct rt2x00_dev *rt2x00dev)
unsigned int i;
for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
- rt73usb_register_read(rt2x00dev, PHY_CSR3, ®);
+ rt73usb_register_read_lock(rt2x00dev, PHY_CSR3, ®);
if (!rt2x00_get_field32(reg, PHY_CSR3_BUSY))
break;
udelay(REGISTER_BUSY_DELAY);
@@ -112,12 +132,15 @@ static void rt73usb_bbp_write(struct rt2x00_dev *rt2x00dev,
{
u32 reg;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
/*
* Wait until the BBP becomes ready.
*/
reg = rt73usb_bbp_check(rt2x00dev);
if (rt2x00_get_field32(reg, PHY_CSR3_BUSY)) {
ERROR(rt2x00dev, "PHY_CSR3 register busy. Write failed.\n");
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
return;
}
@@ -130,7 +153,8 @@ static void rt73usb_bbp_write(struct rt2x00_dev *rt2x00dev,
rt2x00_set_field32(®, PHY_CSR3_BUSY, 1);
rt2x00_set_field32(®, PHY_CSR3_READ_CONTROL, 0);
- rt73usb_register_write(rt2x00dev, PHY_CSR3, reg);
+ rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
@@ -138,12 +162,15 @@ static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
{
u32 reg;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
/*
* Wait until the BBP becomes ready.
*/
reg = rt73usb_bbp_check(rt2x00dev);
if (rt2x00_get_field32(reg, PHY_CSR3_BUSY)) {
ERROR(rt2x00dev, "PHY_CSR3 register busy. Read failed.\n");
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
return;
}
@@ -155,7 +182,7 @@ static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
rt2x00_set_field32(®, PHY_CSR3_BUSY, 1);
rt2x00_set_field32(®, PHY_CSR3_READ_CONTROL, 1);
- rt73usb_register_write(rt2x00dev, PHY_CSR3, reg);
+ rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
/*
* Wait until the BBP becomes ready.
@@ -168,6 +195,7 @@ static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
}
*value = rt2x00_get_field32(reg, PHY_CSR3_VALUE);
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
static void rt73usb_rf_write(struct rt2x00_dev *rt2x00dev,
@@ -179,13 +207,16 @@ static void rt73usb_rf_write(struct rt2x00_dev *rt2x00dev,
if (!word)
return;
+ mutex_lock(&rt2x00dev->usb_cache_mutex);
+
for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
- rt73usb_register_read(rt2x00dev, PHY_CSR4, ®);
+ rt73usb_register_read_lock(rt2x00dev, PHY_CSR4, ®);
if (!rt2x00_get_field32(reg, PHY_CSR4_BUSY))
goto rf_write;
udelay(REGISTER_BUSY_DELAY);
}
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
ERROR(rt2x00dev, "PHY_CSR4 register busy. Write failed.\n");
return;
@@ -203,8 +234,9 @@ rf_write:
rt2x00_set_field32(®, PHY_CSR4_IF_SELECT, 0);
rt2x00_set_field32(®, PHY_CSR4_BUSY, 1);
- rt73usb_register_write(rt2x00dev, PHY_CSR4, reg);
+ rt73usb_register_write_lock(rt2x00dev, PHY_CSR4, reg);
rt2x00_rf_write(rt2x00dev, word, value);
+ mutex_unlock(&rt2x00dev->usb_cache_mutex);
}
#ifdef CONFIG_RT2X00_LIB_DEBUGFS