Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging

* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c: Functions for byte-swapped smbus_write/read_word_data i2c-algo-pca: Return standard fault codes i2c-algo-bit: Return standard fault codes i2c-algo-bit: Be verbose on bus testing failure i2c-algo-bit: Let user test buses without failing i2c/scx200_acb: Fix section mismatch warning in scx200_pci_drv i2c: I2C_ELEKTOR should depend on HAS_IOPORT
2011-10-30 15:54:59 -07:00 · 2011-10-30 15:54:59 -07:00 · 839d881074
--- a/Documentation/i2c/smbus-protocol
+++ b/Documentation/i2c/smbus-protocol
@ -88,6 +88,10 @@ byte. But this time, the data is a complete word (16 bits).

 S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P

+Note the convenience function i2c_smbus_read_word_swapped is
+available for reads where the two data bytes are the other way
+around (not SMBus compliant, but very popular.)
+

 SMBus Write Byte:  i2c_smbus_write_byte_data()
 ==============================================
@ -108,6 +112,10 @@ specified through the Comm byte.

 S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A] P

+Note the convenience function i2c_smbus_write_word_swapped is
+available for writes where the two data bytes are the other way
+around (not SMBus compliant, but very popular.)
+

 SMBus Process Call:  i2c_smbus_process_call()
 =============================================
--- a/drivers/i2c/algos/i2c-algo-bit.c
+++ b/drivers/i2c/algos/i2c-algo-bit.c
@ -47,8 +47,8 @@
 /* ----- global variables ---------------------------------------------	*/

 static int bit_test;	/* see if the line-setting functions work	*/
-module_param(bit_test, bool, 0);
-MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck");
+module_param(bit_test, int, S_IRUGO);
+MODULE_PARM_DESC(bit_test, "lines testing - 0 off; 1 report; 2 fail if stuck");

 #ifdef DEBUG
 static int i2c_debug = 1;
@ -250,7 +250,9 @@ static int test_bus(struct i2c_adapter *i2c_adap)
 	sda = getsda(adap);
 	scl = (adap->getscl == NULL) ? 1 : getscl(adap);
 	if (!scl || !sda) {
-		printk(KERN_WARNING "%s: bus seems to be busy\n", name);
+		printk(KERN_WARNING
+		       "%s: bus seems to be busy (scl=%d, sda=%d)\n",
+		       name, scl, sda);
 		goto bailout;
 	}

@ -441,7 +443,7 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 					acknak(i2c_adap, 0);
 				dev_err(&i2c_adap->dev, "readbytes: invalid "
 					"block length (%d)\n", inval);
-				return -EREMOTEIO;
+				return -EPROTO;
 			}
 			/* The original count value accounts for the extra
 			   bytes, that is, either 1 for a regular transaction,
@ -470,7 +472,7 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 * reads, writes as well as 10bit-addresses.
 * returns:
 *  0 everything went okay, the chip ack'ed, or IGNORE_NAK flag was set
- * -x an error occurred (like: -EREMOTEIO if the device did not answer, or
+ * -x an error occurred (like: -ENXIO if the device did not answer, or
 *	-ETIMEDOUT, for example if the lines are stuck...)
 */
 static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
@ -493,14 +495,14 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 		if ((ret != 1) && !nak_ok)  {
 			dev_err(&i2c_adap->dev,
 				"died at extended address code\n");
-			return -EREMOTEIO;
+			return -ENXIO;
 		}
 		/* the remaining 8 bit address */
 		ret = i2c_outb(i2c_adap, msg->addr & 0x7f);
 		if ((ret != 1) && !nak_ok) {
 			/* the chip did not ack / xmission error occurred */
 			dev_err(&i2c_adap->dev, "died at 2nd address code\n");
-			return -EREMOTEIO;
+			return -ENXIO;
 		}
 		if (flags & I2C_M_RD) {
 			bit_dbg(3, &i2c_adap->dev, "emitting repeated "
@ -512,7 +514,7 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
 			if ((ret != 1) && !nak_ok) {
 				dev_err(&i2c_adap->dev,
 					"died at repeated address code\n");
-				return -EREMOTEIO;
+				return -EIO;
 			}
 		}
 	} else {		/* normal 7bit address	*/
@ -570,7 +572,7 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
 					ret, ret == 1 ? "" : "s");
 			if (ret < pmsg->len) {
 				if (ret >= 0)
-					ret = -EREMOTEIO;
+					ret = -EIO;
 				goto bailout;
 			}
 		} else {
@ -581,7 +583,7 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
 					ret, ret == 1 ? "" : "s");
 			if (ret < pmsg->len) {
 				if (ret >= 0)
-					ret = -EREMOTEIO;
+					ret = -EIO;
 				goto bailout;
 			}
 		}
@ -624,7 +626,7 @@ static int __i2c_bit_add_bus(struct i2c_adapter *adap,

 	if (bit_test) {
 		ret = test_bus(adap);
-		if (ret < 0)
+		if (bit_test >= 2 && ret < 0)
 			return -ENODEV;
 	}

--- a/drivers/i2c/algos/i2c-algo-pca.c
+++ b/drivers/i2c/algos/i2c-algo-pca.c
@ -196,7 +196,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap,
 		} else {
 			dev_dbg(&i2c_adap->dev, "bus is not idle. status is "
 				"%#04x\n", state);
-			return -EAGAIN;
+			return -EBUSY;
 		}
 	}

@ -224,7 +224,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap,
 	}

 	curmsg = 0;
-	ret = -EREMOTEIO;
+	ret = -EIO;
 	while (curmsg < num) {
 		state = pca_status(adap);

@ -259,6 +259,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap,
 		case 0x20: /* SLA+W has been transmitted; NOT ACK has been received */
 			DEB2("NOT ACK received after SLA+W\n");
 			pca_stop(adap);
+			ret = -ENXIO;
 			goto out;

 		case 0x40: /* SLA+R has been transmitted; ACK has been received */
@ -283,6 +284,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap,
 		case 0x48: /* SLA+R has been transmitted; NOT ACK has been received */
 			DEB2("NOT ACK received after SLA+R\n");
 			pca_stop(adap);
+			ret = -ENXIO;
 			goto out;

 		case 0x30: /* Data byte in I2CDAT has been transmitted; NOT ACK has been received */
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@ -789,7 +789,7 @@ config I2C_ACORN

 config I2C_ELEKTOR
 	tristate "Elektor ISA card"
-	depends on ISA && BROKEN_ON_SMP
+	depends on ISA && HAS_IOPORT && BROKEN_ON_SMP
 	select I2C_ALGOPCF
 	help
 	  This supports the PCF8584 ISA bus I2C adapter.  Say Y if you own
--- a/drivers/i2c/busses/scx200_acb.c
+++ b/drivers/i2c/busses/scx200_acb.c
@ -550,7 +550,7 @@ static int __devexit scx200_remove(struct platform_device *pdev)
 	return 0;
 }

-static struct platform_driver scx200_pci_drv = {
+static struct platform_driver scx200_pci_driver = {
 	.driver = {
 		.name = "cs5535-smb",
 		.owner = THIS_MODULE,
@ -593,14 +593,14 @@ static int __init scx200_acb_init(void)
 		return 0;

 	/* No ISA devices; register the platform driver for PCI-based devices */
-	return platform_driver_register(&scx200_pci_drv);
+	return platform_driver_register(&scx200_pci_driver);
 }

 static void __exit scx200_acb_cleanup(void)
 {
 	struct scx200_acb_iface *iface;

-	platform_driver_unregister(&scx200_pci_drv);
+	platform_driver_unregister(&scx200_pci_driver);

 	mutex_lock(&scx200_acb_list_mutex);
 	while ((iface = scx200_acb_list) != NULL) {
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@ -34,6 +34,7 @@
 #include <linux/sched.h>	/* for completion */
 #include <linux/mutex.h>
 #include <linux/of.h>		/* for struct device_node */
+#include <linux/swab.h>		/* for swab16 */

 extern struct bus_type i2c_bus_type;
 extern struct device_type i2c_adapter_type;
@ -88,6 +89,22 @@ extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
 				    u8 command);
 extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
 				     u8 command, u16 value);
+
+static inline s32
+i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command)
+{
+	s32 value = i2c_smbus_read_word_data(client, command);
+
+	return (value < 0) ? value : swab16(value);
+}
+
+static inline s32
+i2c_smbus_write_word_swapped(const struct i2c_client *client,
+			     u8 command, u16 value)
+{
+	return i2c_smbus_write_word_data(client, command, swab16(value));
+}
+
 /* Returns the number of read bytes */
 extern s32 i2c_smbus_read_block_data(const struct i2c_client *client,
 				     u8 command, u8 *values);