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Diffstat (limited to 'drivers/i2c/busses/i2c-mv64xxx.c')
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c54
1 files changed, 34 insertions, 20 deletions
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index bb37e14f3fbd..6356439454ee 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -86,6 +86,8 @@ enum {
};
struct mv64xxx_i2c_data {
+ struct i2c_msg *msgs;
+ int num_msgs;
int irq;
u32 state;
u32 action;
@@ -194,7 +196,7 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
if ((drv_data->bytes_left == 0)
|| (drv_data->aborting
&& (drv_data->byte_posn != 0))) {
- if (drv_data->send_stop) {
+ if (drv_data->send_stop || drv_data->aborting) {
drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
drv_data->state = MV64XXX_I2C_STATE_IDLE;
} else {
@@ -271,12 +273,25 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
{
switch(drv_data->action) {
case MV64XXX_I2C_ACTION_SEND_RESTART:
+ /* We should only get here if we have further messages */
+ BUG_ON(drv_data->num_msgs == 0);
+
drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START;
- drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits,
drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
- drv_data->block = 0;
- wake_up(&drv_data->waitq);
+
+ drv_data->msgs++;
+ drv_data->num_msgs--;
+
+ /* Setup for the next message */
+ mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs);
+
+ /*
+ * We're never at the start of the message here, and by this
+ * time it's already too late to do any protocol mangling.
+ * Thankfully, do not advertise support for that feature.
+ */
+ drv_data->send_stop = drv_data->num_msgs == 1;
break;
case MV64XXX_I2C_ACTION_CONTINUE:
@@ -412,20 +427,15 @@ mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
static int
mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
- int is_first, int is_last)
+ int is_last)
{
unsigned long flags;
spin_lock_irqsave(&drv_data->lock, flags);
mv64xxx_i2c_prepare_for_io(drv_data, msg);
- if (is_first) {
- drv_data->action = MV64XXX_I2C_ACTION_SEND_START;
- drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND;
- } else {
- drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1;
- drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
- }
+ drv_data->action = MV64XXX_I2C_ACTION_SEND_START;
+ drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND;
drv_data->send_stop = is_last;
drv_data->block = 1;
@@ -453,16 +463,20 @@ static int
mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
- int i, rc;
+ int rc, ret = num;
- for (i = 0; i < num; i++) {
- rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[i],
- i == 0, i + 1 == num);
- if (rc < 0)
- return rc;
- }
+ BUG_ON(drv_data->msgs != NULL);
+ drv_data->msgs = msgs;
+ drv_data->num_msgs = num;
+
+ rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1);
+ if (rc < 0)
+ ret = rc;
+
+ drv_data->num_msgs = 0;
+ drv_data->msgs = NULL;
- return num;
+ return ret;
}
static const struct i2c_algorithm mv64xxx_i2c_algo = {
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