Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:

 - regression fixes for i801 and designware

 - better API and leak fix for releasing DMA safe buffers

 - better greppable strings for the bitbang algorithm

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sh_mobile: fix leak when using DMA bounce buffer
  i2c: sh_mobile: define start_ch() void as it only returns 0 anyhow
  i2c: refactor function to release a DMA safe buffer
  i2c: algos: bit: make the error messages grepable
  i2c: designware: Re-init controllers with pm_disabled set on resume
  i2c: i801: Allow ACPI AML access I/O ports not reserved for SMBus

Documentation/i2c/DMA-considerations

@@ -50,10 +50,14 @@ bounce buffer. But you don't need to care about that detail, just use the
 returned buffer. If NULL is returned, the threshold was not met or a bounce
 buffer could not be allocated. Fall back to PIO in that case.
 
-In any case, a buffer obtained from above needs to be released. It ensures data
-is copied back to the message and a potentially used bounce buffer is freed::
+In any case, a buffer obtained from above needs to be released. Another helper
+function ensures a potentially used bounce buffer is freed::
 
-	i2c_release_dma_safe_msg_buf(msg, dma_buf);
+	i2c_put_dma_safe_msg_buf(dma_buf, msg, xferred);
+
+The last argument 'xferred' controls if the buffer is synced back to the
+message or not. No syncing is needed in cases setting up DMA had an error and
+there was no data transferred.
 
 The bounce buffer handling from the core is generic and simple. It will always
 allocate a new bounce buffer. If you want a more sophisticated handling (e.g.

drivers/i2c/algos/i2c-algo-bit.c

@@ -110,8 +110,8 @@ static int sclhi(struct i2c_algo_bit_data *adap)
 	}
 #ifdef DEBUG
 	if (jiffies != start && i2c_debug >= 3)
-		pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go "
-			 "high\n", jiffies - start);
+		pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go high\n",
+			 jiffies - start);
 #endif
 
 done:
@@ -171,8 +171,9 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c)
 		setsda(adap, sb);
 		udelay((adap->udelay + 1) / 2);
 		if (sclhi(adap) < 0) { /* timed out */
-			bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
-				"timeout at bit #%d\n", (int)c, i);
+			bit_dbg(1, &i2c_adap->dev,
+				"i2c_outb: 0x%02x, timeout at bit #%d\n",
+				(int)c, i);
 			return -ETIMEDOUT;
 		}
 		/* FIXME do arbitration here:
@@ -185,8 +186,8 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c)
 	}
 	sdahi(adap);
 	if (sclhi(adap) < 0) { /* timeout */
-		bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
-			"timeout at ack\n", (int)c);
+		bit_dbg(1, &i2c_adap->dev,
+			"i2c_outb: 0x%02x, timeout at ack\n", (int)c);
 		return -ETIMEDOUT;
 	}
 
@@ -215,8 +216,9 @@ static int i2c_inb(struct i2c_adapter *i2c_adap)
 	sdahi(adap);
 	for (i = 0; i < 8; i++) {
 		if (sclhi(adap) < 0) { /* timeout */
-			bit_dbg(1, &i2c_adap->dev, "i2c_inb: timeout at bit "
-				"#%d\n", 7 - i);
+			bit_dbg(1, &i2c_adap->dev,
+				"i2c_inb: timeout at bit #%d\n",
+				7 - i);
 			return -ETIMEDOUT;
 		}
 		indata *= 2;
@@ -265,8 +267,9 @@ static int test_bus(struct i2c_adapter *i2c_adap)
 		goto bailout;
 	}
 	if (!scl) {
-		printk(KERN_WARNING "%s: SCL unexpected low "
-		       "while pulling SDA low!\n", name);
+		printk(KERN_WARNING
+		       "%s: SCL unexpected low while pulling SDA low!\n",
+		       name);
 		goto bailout;
 	}
 
@@ -278,8 +281,9 @@ static int test_bus(struct i2c_adapter *i2c_adap)
 		goto bailout;
 	}
 	if (!scl) {
-		printk(KERN_WARNING "%s: SCL unexpected low "
-		       "while pulling SDA high!\n", name);
+		printk(KERN_WARNING
+		       "%s: SCL unexpected low while pulling SDA high!\n",
+		       name);
 		goto bailout;
 	}
 
@@ -291,8 +295,9 @@ static int test_bus(struct i2c_adapter *i2c_adap)
 		goto bailout;
 	}
 	if (!sda) {
-		printk(KERN_WARNING "%s: SDA unexpected low "
-		       "while pulling SCL low!\n", name);
+		printk(KERN_WARNING
+		       "%s: SDA unexpected low while pulling SCL low!\n",
+		       name);
 		goto bailout;
 	}
 
@@ -304,8 +309,9 @@ static int test_bus(struct i2c_adapter *i2c_adap)
 		goto bailout;
 	}
 	if (!sda) {
-		printk(KERN_WARNING "%s: SDA unexpected low "
-		       "while pulling SCL high!\n", name);
+		printk(KERN_WARNING
+		       "%s: SDA unexpected low while pulling SCL high!\n",
+		       name);
 		goto bailout;
 	}
 
@@ -352,8 +358,8 @@ static int try_address(struct i2c_adapter *i2c_adap,
 		i2c_start(adap);
 	}
 	if (i && ret)
-		bit_dbg(1, &i2c_adap->dev, "Used %d tries to %s client at "
-			"0x%02x: %s\n", i + 1,
+		bit_dbg(1, &i2c_adap->dev,
+			"Used %d tries to %s client at 0x%02x: %s\n", i + 1,
 			addr & 1 ? "read from" : "write to", addr >> 1,
 			ret == 1 ? "success" : "failed, timeout?");
 	return ret;
@@ -442,8 +448,9 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 			if (inval <= 0 || inval > I2C_SMBUS_BLOCK_MAX) {
 				if (!(flags & I2C_M_NO_RD_ACK))
 					acknak(i2c_adap, 0);
-				dev_err(&i2c_adap->dev, "readbytes: invalid "
-					"block length (%d)\n", inval);
+				dev_err(&i2c_adap->dev,
+					"readbytes: invalid block length (%d)\n",
+					inval);
 				return -EPROTO;
 			}
 			/* The original count value accounts for the extra
@@ -506,8 +513,8 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 			return -ENXIO;
 		}
 		if (flags & I2C_M_RD) {
-			bit_dbg(3, &i2c_adap->dev, "emitting repeated "
-				"start condition\n");
+			bit_dbg(3, &i2c_adap->dev,
+				"emitting repeated start condition\n");
 			i2c_repstart(adap);
 			/* okay, now switch into reading mode */
 			addr |= 0x01;
@@ -564,8 +571,8 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
 			}
 			ret = bit_doAddress(i2c_adap, pmsg);
 			if ((ret != 0) && !nak_ok) {
-				bit_dbg(1, &i2c_adap->dev, "NAK from "
-					"device addr 0x%02x msg #%d\n",
+				bit_dbg(1, &i2c_adap->dev,
+					"NAK from device addr 0x%02x msg #%d\n",
 					msgs[i].addr, i);
 				goto bailout;
 			}

drivers/i2c/busses/i2c-designware-master.c

@@ -708,7 +708,6 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
 	i2c_set_adapdata(adap, dev);
 
 	if (dev->pm_disabled) {
-		dev_pm_syscore_device(dev->dev, true);
 		irq_flags = IRQF_NO_SUSPEND;
 	} else {
 		irq_flags = IRQF_SHARED | IRQF_COND_SUSPEND;

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -434,6 +434,9 @@ static int dw_i2c_plat_suspend(struct device *dev)
 {
 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 
+	if (i_dev->pm_disabled)
+		return 0;
+
 	i_dev->disable(i_dev);
 	i2c_dw_prepare_clk(i_dev, false);
 
@@ -444,7 +447,9 @@ static int dw_i2c_plat_resume(struct device *dev)
 {
 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 
-	i2c_dw_prepare_clk(i_dev, true);
+	if (!i_dev->pm_disabled)
+		i2c_dw_prepare_clk(i_dev, true);
+
 	i_dev->init(i_dev);
 
 	return 0;

drivers/i2c/busses/i2c-i801.c

@@ -1415,6 +1415,13 @@ static void i801_add_tco(struct i801_priv *priv)
 }
 
 #ifdef CONFIG_ACPI
+static bool i801_acpi_is_smbus_ioport(const struct i801_priv *priv,
+				      acpi_physical_address address)
+{
+	return address >= priv->smba &&
+	       address <= pci_resource_end(priv->pci_dev, SMBBAR);
+}
+
 static acpi_status
 i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
 		     u64 *value, void *handler_context, void *region_context)
@@ -1430,7 +1437,7 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
 	 */
 	mutex_lock(&priv->acpi_lock);
 
-	if (!priv->acpi_reserved) {
+	if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) {
 		priv->acpi_reserved = true;
 
 		dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n");

drivers/i2c/busses/i2c-sh_mobile.c

@@ -507,8 +507,6 @@ static void sh_mobile_i2c_dma_callback(void *data)
 	pd->pos = pd->msg->len;
 	pd->stop_after_dma = true;
 
-	i2c_release_dma_safe_msg_buf(pd->msg, pd->dma_buf);
-
 	iic_set_clr(pd, ICIC, 0, ICIC_TDMAE | ICIC_RDMAE);
 }
 
@@ -602,8 +600,8 @@ static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd)
 	dma_async_issue_pending(chan);
 }
 
-static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg,
-		    bool do_init)
+static void start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg,
+		     bool do_init)
 {
 	if (do_init) {
 		/* Initialize channel registers */
@@ -627,7 +625,6 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg,
 
 	/* Enable all interrupts to begin with */
 	iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
-	return 0;
 }
 
 static int poll_dte(struct sh_mobile_i2c_data *pd)
@@ -698,9 +695,7 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
 		pd->send_stop = i == num - 1 || msg->flags & I2C_M_STOP;
 		pd->stop_after_dma = false;
 
-		err = start_ch(pd, msg, do_start);
-		if (err)
-			break;
+		start_ch(pd, msg, do_start);
 
 		if (do_start)
 			i2c_op(pd, OP_START, 0);
@@ -709,6 +704,10 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
 		timeout = wait_event_timeout(pd->wait,
 				       pd->sr & (ICSR_TACK | SW_DONE),
 				       adapter->timeout);
+
+		/* 'stop_after_dma' tells if DMA transfer was complete */
+		i2c_put_dma_safe_msg_buf(pd->dma_buf, pd->msg, pd->stop_after_dma);
+
 		if (!timeout) {
 			dev_err(pd->dev, "Transfer request timed out\n");
 			if (pd->dma_direction != DMA_NONE)

drivers/i2c/i2c-core-base.c

@@ -2293,21 +2293,22 @@ u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold)
 EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf);
 
 /**
- * i2c_release_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg
- * @msg: the message to be synced with
+ * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg
  * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL.
+ * @msg: the message which the buffer corresponds to
+ * @xferred: bool saying if the message was transferred
  */
-void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf)
+void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred)
 {
 	if (!buf || buf == msg->buf)
 		return;
 
-	if (msg->flags & I2C_M_RD)
+	if (xferred && msg->flags & I2C_M_RD)
 		memcpy(msg->buf, buf, msg->len);
 
 	kfree(buf);
 }
-EXPORT_SYMBOL_GPL(i2c_release_dma_safe_msg_buf);
+EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf);
 
 MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
 MODULE_DESCRIPTION("I2C-Bus main module");

include/linux/i2c.h

@@ -855,7 +855,7 @@ static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
 }
 
 u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold);
-void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf);
+void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred);
 
 int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr);
 /**