Merge tag 'linux-can-fixes-for-3.15-20140401' of git://gitorious.org/linux-can/linux-can

linux-can-fixes-for-3.15-20140401

Marc Kleine-Budde says:

====================
this is a pull request of 16 patches for the 3.15 release cycle.

Bjorn Van Tilt contributes a patch which fixes a memory leak in usb_8dev's
usb_8dev_start_xmit()s error path. A patch by Robert Schwebel fixes a typo in
the can documentation. The remaining patches all target the c_can driver. Two
of them are by me; they add a missing netif_napi_del() and return value
checking. Thomas Gleixner contributes 12 patches, which address several
shortcomings in the driver like hardware initialisation, concurrency, message
ordering and poor performance.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/can.txt

@@ -1017,7 +1017,7 @@ solution for a couple of reasons:
 	in case of a bus-off condition after the specified delay time
 	in milliseconds. By default it's off.
 
-    "bitrate 125000 sample_point 0.875"
+    "bitrate 125000 sample-point 0.875"
 	Shows the real bit-rate in bits/sec and the sample-point in the
 	range 0.000..0.999. If the calculation of bit-timing parameters
 	is enabled in the kernel (CONFIG_CAN_CALC_BITTIMING=y), the

drivers/net/can/c_can/c_can.h

@@ -22,6 +22,33 @@
 #ifndef C_CAN_H
 #define C_CAN_H
 
+/*
+ * IFx register masks:
+ * allow easy operation on 16-bit registers when the
+ * argument is 32-bit instead
+ */
+#define IFX_WRITE_LOW_16BIT(x)	((x) & 0xFFFF)
+#define IFX_WRITE_HIGH_16BIT(x)	(((x) & 0xFFFF0000) >> 16)
+
+/* message object split */
+#define C_CAN_NO_OF_OBJECTS	32
+#define C_CAN_MSG_OBJ_RX_NUM	16
+#define C_CAN_MSG_OBJ_TX_NUM	16
+
+#define C_CAN_MSG_OBJ_RX_FIRST	1
+#define C_CAN_MSG_OBJ_RX_LAST	(C_CAN_MSG_OBJ_RX_FIRST + \
+				C_CAN_MSG_OBJ_RX_NUM - 1)
+
+#define C_CAN_MSG_OBJ_TX_FIRST	(C_CAN_MSG_OBJ_RX_LAST + 1)
+#define C_CAN_MSG_OBJ_TX_LAST	(C_CAN_MSG_OBJ_TX_FIRST + \
+				C_CAN_MSG_OBJ_TX_NUM - 1)
+
+#define C_CAN_MSG_OBJ_RX_SPLIT	9
+#define C_CAN_MSG_RX_LOW_LAST	(C_CAN_MSG_OBJ_RX_SPLIT - 1)
+
+#define C_CAN_NEXT_MSG_OBJ_MASK	(C_CAN_MSG_OBJ_TX_NUM - 1)
+#define RECEIVE_OBJECT_BITS	0x0000ffff
+
 enum reg {
 	C_CAN_CTRL_REG = 0,
 	C_CAN_CTRL_EX_REG,
@@ -156,6 +183,7 @@ struct c_can_priv {
 	struct napi_struct napi;
 	struct net_device *dev;
 	struct device *device;
+	spinlock_t xmit_lock;
 	int tx_object;
 	int current_status;
 	int last_status;
@@ -172,6 +200,7 @@ struct c_can_priv {
 	u32 __iomem *raminit_ctrlreg;
 	unsigned int instance;
 	void (*raminit) (const struct c_can_priv *priv, bool enable);
+	u32 dlc[C_CAN_MSG_OBJ_TX_NUM];
 };
 
 struct net_device *alloc_c_can_dev(void);

drivers/net/can/c_can/c_can_platform.c

@@ -37,8 +37,10 @@
 
 #include "c_can.h"
 
-#define CAN_RAMINIT_START_MASK(i)	(1 << (i))
-
+#define CAN_RAMINIT_START_MASK(i)	(0x001 << (i))
+#define CAN_RAMINIT_DONE_MASK(i)	(0x100 << (i))
+#define CAN_RAMINIT_ALL_MASK(i)		(0x101 << (i))
+static DEFINE_SPINLOCK(raminit_lock);
 /*
  * 16-bit c_can registers can be arranged differently in the memory
  * architecture of different implementations. For example: 16-bit
@@ -69,16 +71,41 @@ static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
 	writew(val, priv->base + 2 * priv->regs[index]);
 }
 
+static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask,
+				  u32 val)
+{
+	/* We look only at the bits of our instance. */
+	val &= mask;
+	while ((readl(priv->raminit_ctrlreg) & mask) != val)
+		udelay(1);
+}
+
 static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
 {
-	u32 val;
-
-	val = readl(priv->raminit_ctrlreg);
-	if (enable)
-		val |= CAN_RAMINIT_START_MASK(priv->instance);
-	else
-		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
-	writel(val, priv->raminit_ctrlreg);
+	u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
+	u32 ctrl;
+
+	spin_lock(&raminit_lock);
+
+	ctrl = readl(priv->raminit_ctrlreg);
+	/* We clear the done and start bit first. The start bit is
+	 * looking at the 0 -> transition, but is not self clearing;
+	 * And we clear the init done bit as well.
+	 */
+	ctrl &= ~CAN_RAMINIT_START_MASK(priv->instance);
+	ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+	writel(ctrl, priv->raminit_ctrlreg);
+	ctrl &= ~CAN_RAMINIT_DONE_MASK(priv->instance);
+	c_can_hw_raminit_wait(priv, ctrl, mask);
+
+	if (enable) {
+		/* Set start bit and wait for the done bit. */
+		ctrl |= CAN_RAMINIT_START_MASK(priv->instance);
+		writel(ctrl, priv->raminit_ctrlreg);
+		ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+		c_can_hw_raminit_wait(priv, ctrl, mask);
+	}
+	spin_unlock(&raminit_lock);
 }
 
 static struct platform_device_id c_can_id_table[] = {

drivers/net/can/usb/usb_8dev.c

@@ -697,8 +697,8 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
 	return NETDEV_TX_OK;
 
 nofreecontext:
-	usb_unanchor_urb(urb);
 	usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
+	usb_free_urb(urb);
 
 	netdev_warn(netdev, "couldn't find free context");