Author: manu
Date: Fri Jan 10 18:52:14 2020
New Revision: 356609
URL: https://svnweb.freebsd.org/changeset/base/356609
Log:
twsi: Rework how we handle the i2c messages
We use to handle each message separately in i2c_transfer but that cannot
work with message with NOSTOP as it confuses the controller that we disable
the interrupts and start a new message.
Handle every message in the interrupt handler and fire a new start condition
if the previous message have NOSTOP, the controller understand this as a
repeated start.
This fixes booting on Allwinner A10/A20 platform where before the i2c
controller
used to write 0 to the PMIC register that control the regulators as it though
that
this was the continuation of the write message.
Tested on: A20 BananaPi, Cubieboard 1 (kevans)
Reported by: kevans
MFC after: 1 month
Modified:
head/sys/dev/iicbus/twsi/twsi.c
head/sys/dev/iicbus/twsi/twsi.h
Modified: head/sys/dev/iicbus/twsi/twsi.c
==============================================================================
--- head/sys/dev/iicbus/twsi/twsi.c Fri Jan 10 18:48:11 2020
(r356608)
+++ head/sys/dev/iicbus/twsi/twsi.c Fri Jan 10 18:52:14 2020
(r356609)
@@ -481,7 +481,6 @@ static int
twsi_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
{
struct twsi_softc *sc;
- int i;
sc = device_get_softc(dev);
@@ -495,28 +494,25 @@ twsi_transfer(device_t dev, struct iic_msg *msgs, uint
TWSI_WRITE(sc, sc->reg_control, sc->control_val);
debugf(dev, "transmitting %d messages\n", nmsgs);
debugf(sc->dev, "status=%x\n", TWSI_READ(sc, sc->reg_status));
- for (i = 0; i < nmsgs && sc->error == 0; i++) {
- sc->transfer = 1;
- sc->msg = &msgs[i];
- debugf(dev, "msg[%d] flags: %x\n", i, msgs[i].flags);
- debugf(dev, "msg[%d] len: %d\n", i, msgs[i].len);
+ sc->nmsgs = nmsgs;
+ sc->msgs = msgs;
+ sc->msg_idx = 0;
+ sc->transfer = 1;
- /* Send start and re-enable interrupts */
- sc->control_val = TWSI_CONTROL_TWSIEN |
- TWSI_CONTROL_INTEN | TWSI_CONTROL_ACK;
- if (sc->msg->len == 1)
- sc->control_val &= ~TWSI_CONTROL_ACK;
- TWSI_WRITE(sc, sc->reg_control, sc->control_val |
TWSI_CONTROL_START);
- while (sc->error == 0 && sc->transfer != 0) {
- pause_sbt("twsi", SBT_1MS * 30, SBT_1MS, 0);
- }
+ /* Send start and re-enable interrupts */
+ sc->control_val = TWSI_CONTROL_TWSIEN |
+ TWSI_CONTROL_INTEN | TWSI_CONTROL_ACK;
+ if (sc->msgs[0].len == 1)
+ sc->control_val &= ~TWSI_CONTROL_ACK;
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val | TWSI_CONTROL_START);
+ while (sc->error == 0 && sc->transfer != 0) {
+ pause_sbt("twsi", SBT_1MS * 30, SBT_1MS, 0);
+ }
+ debugf(sc->dev, "pause finish\n");
- debugf(dev, "Done with msg[%d]\n", i);
- if (sc->error) {
- debugf(sc->dev, "Error, aborting (%d)\n", sc->error);
- TWSI_WRITE(sc, sc->reg_control, 0);
- goto out;
- }
+ if (sc->error) {
+ debugf(sc->dev, "Error, aborting (%d)\n", sc->error);
+ TWSI_WRITE(sc, sc->reg_control, 0);
}
/* Disable module and interrupts */
@@ -524,7 +520,6 @@ twsi_transfer(device_t dev, struct iic_msg *msgs, uint
TWSI_WRITE(sc, sc->reg_control, 0);
debugf(sc->dev, "status=%x\n", TWSI_READ(sc, sc->reg_status));
-out:
return (sc->error);
}
@@ -537,122 +532,123 @@ twsi_intr(void *arg)
sc = arg;
- debugf(sc->dev, "Got interrupt\n");
+ debugf(sc->dev, "Got interrupt Current msg=%x\n", sc->msg_idx);
- while (TWSI_READ(sc, sc->reg_control) & TWSI_CONTROL_IFLG) {
- status = TWSI_READ(sc, sc->reg_status);
- debugf(sc->dev, "status=%x\n", status);
+ status = TWSI_READ(sc, sc->reg_status);
+ debugf(sc->dev, "initial status=%x\n", status);
- switch (status) {
- case TWSI_STATUS_START:
- case TWSI_STATUS_RPTD_START:
- /* Transmit the address */
- debugf(sc->dev, "Send the address\n");
+ switch (status) {
+ case TWSI_STATUS_START:
+ case TWSI_STATUS_RPTD_START:
+ /* Transmit the address */
+ debugf(sc->dev, "Send the address\n");
- if (sc->msg->flags & IIC_M_RD)
- TWSI_WRITE(sc, sc->reg_data,
- sc->msg->slave | LSB);
- else
- TWSI_WRITE(sc, sc->reg_data,
- sc->msg->slave & ~LSB);
+ if (sc->msgs[sc->msg_idx].flags & IIC_M_RD)
+ TWSI_WRITE(sc, sc->reg_data,
+ sc->msgs[sc->msg_idx].slave | LSB);
+ else
+ TWSI_WRITE(sc, sc->reg_data,
+ sc->msgs[sc->msg_idx].slave & ~LSB);
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val);
+ break;
- TWSI_WRITE(sc, sc->reg_control, sc->control_val);
- break;
+ case TWSI_STATUS_ADDR_W_ACK:
+ debugf(sc->dev, "Ack received after transmitting the address
(write)\n");
+ /* Directly send the first byte */
+ sc->sent_bytes = 0;
+ debugf(sc->dev, "Sending byte 0 = %x\n",
sc->msgs[sc->msg_idx].buf[0]);
+ TWSI_WRITE(sc, sc->reg_data, sc->msgs[sc->msg_idx].buf[0]);
- case TWSI_STATUS_ADDR_W_ACK:
- debugf(sc->dev, "Ack received after transmitting the
address\n");
- /* Directly send the first byte */
- sc->sent_bytes = 0;
- debugf(sc->dev, "Sending byte 0 = %x\n",
sc->msg->buf[0]);
- TWSI_WRITE(sc, sc->reg_data, sc->msg->buf[0]);
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val);
+ break;
- TWSI_WRITE(sc, sc->reg_control, sc->control_val);
- break;
+ case TWSI_STATUS_ADDR_R_ACK:
+ debugf(sc->dev, "Ack received after transmitting the address
(read)\n");
+ sc->recv_bytes = 0;
- case TWSI_STATUS_ADDR_R_ACK:
- debugf(sc->dev, "Ack received after transmitting the
address\n");
- sc->recv_bytes = 0;
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val);
+ break;
- TWSI_WRITE(sc, sc->reg_control, sc->control_val);
- break;
+ case TWSI_STATUS_ADDR_W_NACK:
+ case TWSI_STATUS_ADDR_R_NACK:
+ debugf(sc->dev, "No ack received after transmitting the
address\n");
+ sc->transfer = 0;
+ sc->error = ETIMEDOUT;
+ sc->control_val = 0;
+ wakeup(sc);
+ break;
- case TWSI_STATUS_ADDR_W_NACK:
- case TWSI_STATUS_ADDR_R_NACK:
- debugf(sc->dev, "No ack received after transmitting the
address\n");
- sc->transfer = 0;
- sc->error = ETIMEDOUT;
- sc->control_val = 0;
- wakeup(sc);
- break;
-
- case TWSI_STATUS_DATA_WR_ACK:
- debugf(sc->dev, "Ack received after transmitting
data\n");
- if (sc->sent_bytes++ == (sc->msg->len - 1)) {
- debugf(sc->dev, "Done sending all the bytes\n");
- /* Send stop, no interrupts on stop */
- if (!(sc->msg->flags & IIC_M_NOSTOP)) {
- debugf(sc->dev, "Done TX data, send
stop\n");
- TWSI_WRITE(sc, sc->reg_control,
- sc->control_val | TWSI_CONTROL_STOP);
- } else {
- sc->control_val &= ~TWSI_CONTROL_INTEN;
- TWSI_WRITE(sc, sc->reg_control,
- sc->control_val);
- }
- transfer_done = 1;
- } else {
- debugf(sc->dev, "Sending byte %d = %x\n",
- sc->sent_bytes,
- sc->msg->buf[sc->sent_bytes]);
- TWSI_WRITE(sc, sc->reg_data,
- sc->msg->buf[sc->sent_bytes]);
+ case TWSI_STATUS_DATA_WR_ACK:
+ debugf(sc->dev, "Ack received after transmitting data\n");
+ if (sc->sent_bytes++ == (sc->msgs[sc->msg_idx].len - 1)) {
+ debugf(sc->dev, "Done sending all the bytes for msg
%d\n", sc->msg_idx);
+ /* Send stop, no interrupts on stop */
+ if (!(sc->msgs[sc->msg_idx].flags & IIC_M_NOSTOP)) {
+ debugf(sc->dev, "Done TX data, send stop\n");
TWSI_WRITE(sc, sc->reg_control,
- sc->control_val);
+ sc->control_val | TWSI_CONTROL_STOP);
+ } else {
+ debugf(sc->dev, "Done TX data with NO_STOP\n");
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val
| TWSI_CONTROL_START);
}
+ sc->msg_idx++;
+ if (sc->msg_idx == sc->nmsgs) {
+ debugf(sc->dev, "transfer_done=1\n");
+ transfer_done = 1;
+ }
+ } else {
+ debugf(sc->dev, "Sending byte %d = %x\n",
+ sc->sent_bytes,
+ sc->msgs[sc->msg_idx].buf[sc->sent_bytes]);
+ TWSI_WRITE(sc, sc->reg_data,
+ sc->msgs[sc->msg_idx].buf[sc->sent_bytes]);
+ TWSI_WRITE(sc, sc->reg_control,
+ sc->control_val);
+ }
+ break;
- break;
- case TWSI_STATUS_DATA_RD_ACK:
- debugf(sc->dev, "Ack received after receiving data\n");
- debugf(sc->dev, "msg_len=%d recv_bytes=%d\n",
sc->msg->len, sc->recv_bytes);
- sc->msg->buf[sc->recv_bytes++] = TWSI_READ(sc,
sc->reg_data);
+ case TWSI_STATUS_DATA_RD_ACK:
+ debugf(sc->dev, "Ack received after receiving data\n");
+ debugf(sc->dev, "msg_len=%d recv_bytes=%d\n",
sc->msgs[sc->msg_idx].len, sc->recv_bytes);
+ sc->msgs[sc->msg_idx].buf[sc->recv_bytes++] = TWSI_READ(sc,
sc->reg_data);
- /* If we only have one byte left, disable ACK */
- if (sc->msg->len - sc->recv_bytes == 1)
- sc->control_val &= ~TWSI_CONTROL_ACK;
- TWSI_WRITE(sc, sc->reg_control, sc->control_val);
- break;
+ /* If we only have one byte left, disable ACK */
+ if (sc->msgs[sc->msg_idx].len - sc->recv_bytes == 1)
+ sc->control_val &= ~TWSI_CONTROL_ACK;
+ if (sc->msgs[sc->msg_idx].len - sc->recv_bytes) {
+ sc->msg_idx++;
+ if (sc->msg_idx == sc->nmsgs - 1)
+ transfer_done = 1;
+ }
+ TWSI_WRITE(sc, sc->reg_control, sc->control_val);
+ break;
- case TWSI_STATUS_DATA_RD_NOACK:
- if (sc->msg->len - sc->recv_bytes == 1) {
- sc->msg->buf[sc->recv_bytes++] = TWSI_READ(sc,
sc->reg_data);
- debugf(sc->dev, "Done RX data, send stop
(2)\n");
- if (!(sc->msg->flags & IIC_M_NOSTOP))
- TWSI_WRITE(sc, sc->reg_control,
- sc->control_val | TWSI_CONTROL_STOP);
- } else {
- debugf(sc->dev, "No ack when receiving data\n");
- sc->error = ENXIO;
- sc->control_val = 0;
- }
- sc->transfer = 0;
- transfer_done = 1;
- break;
-
- default:
- debugf(sc->dev, "status=%x hot handled\n", status);
- sc->transfer = 0;
+ case TWSI_STATUS_DATA_RD_NOACK:
+ if (sc->msgs[sc->msg_idx].len - sc->recv_bytes == 1) {
+ sc->msgs[sc->msg_idx].buf[sc->recv_bytes++] =
TWSI_READ(sc, sc->reg_data);
+ debugf(sc->dev, "Done RX data, send stop (2)\n");
+ if (!(sc->msgs[sc->msg_idx].flags & IIC_M_NOSTOP))
+ TWSI_WRITE(sc, sc->reg_control,
+ sc->control_val | TWSI_CONTROL_STOP);
+ } else {
+ debugf(sc->dev, "No ack when receiving data\n");
sc->error = ENXIO;
sc->control_val = 0;
- wakeup(sc);
- break;
}
+ sc->transfer = 0;
+ transfer_done = 1;
+ break;
- if (sc->need_ack)
- TWSI_WRITE(sc, sc->reg_control,
- sc->control_val | TWSI_CONTROL_IFLG);
+ default:
+ debugf(sc->dev, "status=%x hot handled\n", status);
+ sc->transfer = 0;
+ sc->error = ENXIO;
+ sc->control_val = 0;
+ wakeup(sc);
+ break;
}
- debugf(sc->dev, "Done with interrupts\n");
+ debugf(sc->dev, "Done with interrupts\n\n");
if (transfer_done == 1) {
sc->transfer = 0;
wakeup(sc);
Modified: head/sys/dev/iicbus/twsi/twsi.h
==============================================================================
--- head/sys/dev/iicbus/twsi/twsi.h Fri Jan 10 18:48:11 2020
(r356608)
+++ head/sys/dev/iicbus/twsi/twsi.h Fri Jan 10 18:52:14 2020
(r356609)
@@ -57,7 +57,9 @@ struct twsi_softc {
void * intrhand;
bool have_intr;
- struct iic_msg *msg;
+ struct iic_msg *msgs;
+ uint32_t nmsgs;
+ uint32_t msg_idx;
uint16_t sent_bytes;
uint16_t recv_bytes;
int transfer;
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