[RFT] rtl8187: use DMA-aware buffers with usb_control_msg

John W. Linville
2009-05-06T18:16:45Z

This definitely needs to fail more gracefully in the event of a
kmalloc failure...

Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
drivers/net/wireless/rtl818x/rtl8187.h | 72 ++++++++++++++++++++----
drivers/net/wireless/rtl818x/rtl8187_rtl8225.c | 11 +++-
2 files changed, 71 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/rtl818x/rtl8187.h b/drivers/net/wireless/rtl818x/rtl8187.h
index 622196d..600ae34 100644
--- a/drivers/net/wireless/rtl818x/rtl8187.h
+++ b/drivers/net/wireless/rtl818x/rtl8187.h
@@ -134,13 +134,21 @@ void rtl8187_write_phy(struct ieee80211_hw *dev, u8 addr, u32 data);
static inline u8 rtl818x_ioread8_idx(struct rtl8187_priv *priv,
u8 *addr, u8 idx)
{
- u8 val;
+ u8 val, *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */

usb_control_msg(priv->udev, usb_rcvctrlpipe(priv->udev, 0),
RTL8187_REQ_GET_REG, RTL8187_REQT_READ,
- (unsigned long)addr, idx & 0x03, &val,
+ (unsigned long)addr, idx & 0x03, buf,
sizeof(val), HZ / 2);

+ val = *buf;
+ kfree(buf);
+
return val;
}

@@ -152,13 +160,21 @@ static inline u8 rtl818x_ioread8(struct rtl8187_priv *priv, u8 *addr)
static inline u16 rtl818x_ioread16_idx(struct rtl8187_priv *priv,
__le16 *addr, u8 idx)
{
- __le16 val;
+ __le16 val, *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */

usb_control_msg(priv->udev, usb_rcvctrlpipe(priv->udev, 0),
RTL8187_REQ_GET_REG, RTL8187_REQT_READ,
- (unsigned long)addr, idx & 0x03, &val,
+ (unsigned long)addr, idx & 0x03, buf,
sizeof(val), HZ / 2);

+ val = *buf;
+ kfree(buf);
+
return le16_to_cpu(val);
}

@@ -170,13 +186,21 @@ static inline u16 rtl818x_ioread16(struct rtl8187_priv *priv, __le16 *addr)
static inline u32 rtl818x_ioread32_idx(struct rtl8187_priv *priv,
__le32 *addr, u8 idx)
{
- __le32 val;
+ __le32 val, *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */

usb_control_msg(priv->udev, usb_rcvctrlpipe(priv->udev, 0),
RTL8187_REQ_GET_REG, RTL8187_REQT_READ,
- (unsigned long)addr, idx & 0x03, &val,
+ (unsigned long)addr, idx & 0x03, buf,
sizeof(val), HZ / 2);

+ val = *buf;
+ kfree(buf);
+
return le32_to_cpu(val);
}

@@ -188,10 +212,20 @@ static inline u32 rtl818x_ioread32(struct rtl8187_priv *priv, __le32 *addr)
static inline void rtl818x_iowrite8_idx(struct rtl8187_priv *priv,
u8 *addr, u8 val, u8 idx)
{
+ u8 *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */
+ *buf = val;
+
usb_control_msg(priv->udev, usb_sndctrlpipe(priv->udev, 0),
RTL8187_REQ_SET_REG, RTL8187_REQT_WRITE,
- (unsigned long)addr, idx & 0x03, &val,
+ (unsigned long)addr, idx & 0x03, buf,
sizeof(val), HZ / 2);
+
+ kfree(buf);
}

static inline void rtl818x_iowrite8(struct rtl8187_priv *priv, u8 *addr, u8 val)
@@ -202,12 +236,20 @@ static inline void rtl818x_iowrite8(struct rtl8187_priv *priv, u8 *addr, u8 val)
static inline void rtl818x_iowrite16_idx(struct rtl8187_priv *priv,
__le16 *addr, u16 val, u8 idx)
{
- __le16 buf = cpu_to_le16(val);
+ __le16 *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */
+ *buf = cpu_to_le16(val);

usb_control_msg(priv->udev, usb_sndctrlpipe(priv->udev, 0),
RTL8187_REQ_SET_REG, RTL8187_REQT_WRITE,
- (unsigned long)addr, idx & 0x03, &buf, sizeof(buf),
+ (unsigned long)addr, idx & 0x03, buf, sizeof(*buf),
HZ / 2);
+
+ kfree(buf);
}

static inline void rtl818x_iowrite16(struct rtl8187_priv *priv, __le16 *addr,
@@ -219,12 +261,20 @@ static inline void rtl818x_iowrite16(struct rtl8187_priv *priv, __le16 *addr,
static inline void rtl818x_iowrite32_idx(struct rtl8187_priv *priv,
__le32 *addr, u32 val, u8 idx)
{
- __le32 buf = cpu_to_le32(val);
+ __le32 *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */
+ *buf = cpu_to_le32(val);

usb_control_msg(priv->udev, usb_sndctrlpipe(priv->udev, 0),
RTL8187_REQ_SET_REG, RTL8187_REQT_WRITE,
- (unsigned long)addr, idx & 0x03, &buf, sizeof(buf),
+ (unsigned long)addr, idx & 0x03, buf, sizeof(*buf),
HZ / 2);
+
+ kfree(buf);
}

static inline void rtl818x_iowrite32(struct rtl8187_priv *priv, __le32 *addr,
diff --git a/drivers/net/wireless/rtl818x/rtl8187_rtl8225.c b/drivers/net/wireless/rtl818x/rtl8187_rtl8225.c
index 78df281..6c6dba2 100644
--- a/drivers/net/wireless/rtl818x/rtl8187_rtl8225.c
+++ b/drivers/net/wireless/rtl818x/rtl8187_rtl8225.c
@@ -70,6 +70,13 @@ static void rtl8225_write_8051(struct ieee80211_hw *dev, u8 addr, __le16 data)
{
struct rtl8187_priv *priv = dev->priv;
u16 reg80, reg82, reg84;
+ __le16 *buf;
+
+ /* Use "DMA-aware" buffer. */
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ BUG(); /* TODO -- handle this more gracefully */
+ *buf = data;

reg80 = rtl818x_ioread16(priv, &priv->map->RFPinsOutput);
reg82 = rtl818x_ioread16(priv, &priv->map->RFPinsEnable);
@@ -90,13 +97,15 @@ static void rtl8225_write_8051(struct ieee80211_hw *dev, u8 addr, __le16 data)

usb_control_msg(priv->udev, usb_sndctrlpipe(priv->udev, 0),
RTL8187_REQ_SET_REG, RTL8187_REQT_WRITE,
- addr, 0x8225, &data, sizeof(data), HZ / 2);
+ addr, 0x8225, buf, sizeof(*buf), HZ / 2);

rtl818x_iowrite16(priv, &priv->map->RFPinsOutput, reg80 | (1 << 2));
udelay(10);

rtl818x_iowrite16(priv, &priv->map->RFPinsOutput, reg80 | (1 << 2));
rtl818x_iowrite16(priv, &priv->map->RFPinsSelect, reg84);
+
+ kfree(buf);
}

static void rtl8225_write(struct ieee80211_hw *dev, u8 addr, u16 data)
--
1.6.0.6