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Diffstat (limited to 'drivers/i2c/algos/i2c-algo-bit.c')
-rw-r--r--drivers/i2c/algos/i2c-algo-bit.c49
1 files changed, 29 insertions, 20 deletions
diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c
index d6d58684712..65ef9664d5d 100644
--- a/drivers/i2c/algos/i2c-algo-bit.c
+++ b/drivers/i2c/algos/i2c-algo-bit.c
@@ -15,16 +15,16 @@
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ MA 02110-1301 USA.
* ------------------------------------------------------------------------- */
/* With some changes from Frodo Looijaard <frodol@dds.nl>, Kyösti Mälkki
- <kmalkki@cc.hut.fi> and Jean Delvare <khali@linux-fr.org> */
+ <kmalkki@cc.hut.fi> and Jean Delvare <jdelvare@suse.de> */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
-#include <linux/init.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/i2c.h>
@@ -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;
@@ -103,9 +103,15 @@ static int sclhi(struct i2c_algo_bit_data *adap)
* chips may hold it low ("clock stretching") while they
* are processing data internally.
*/
- if (time_after(jiffies, start + adap->timeout))
+ if (time_after(jiffies, start + adap->timeout)) {
+ /* Test one last time, as we may have been preempted
+ * between last check and timeout test.
+ */
+ if (getscl(adap))
+ break;
return -ETIMEDOUT;
- cond_resched();
+ }
+ cpu_relax();
}
#ifdef DEBUG
if (jiffies != start && i2c_debug >= 3)
@@ -250,7 +256,9 @@ 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 +449,7 @@ 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 +478,7 @@ 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)
@@ -486,21 +494,21 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
if (flags & I2C_M_TEN) {
/* a ten bit address */
- addr = 0xf0 | ((msg->addr >> 7) & 0x03);
+ addr = 0xf0 | ((msg->addr >> 7) & 0x06);
bit_dbg(2, &i2c_adap->dev, "addr0: %d\n", addr);
/* try extended address code...*/
ret = try_address(i2c_adap, addr, retries);
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);
+ ret = i2c_outb(i2c_adap, msg->addr & 0xff);
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 +520,7 @@ 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 +578,7 @@ 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 +589,7 @@ 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;
}
}
@@ -599,7 +607,7 @@ bailout:
static u32 bit_func(struct i2c_adapter *adap)
{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ return I2C_FUNC_I2C | I2C_FUNC_NOSTART | I2C_FUNC_SMBUS_EMUL |
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
@@ -608,10 +616,11 @@ static u32 bit_func(struct i2c_adapter *adap)
/* -----exported algorithm data: ------------------------------------- */
-static const struct i2c_algorithm i2c_bit_algo = {
+const struct i2c_algorithm i2c_bit_algo = {
.master_xfer = bit_xfer,
.functionality = bit_func,
};
+EXPORT_SYMBOL(i2c_bit_algo);
/*
* registering functions to load algorithms at runtime
@@ -624,7 +633,7 @@ 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;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-13 04:58:38 +0000