The timeout when waiting for data to be received for polled mode is
too small for taling to the BMC on the Ampere/Lenovo arm64 server.
This bumps it to 50 ms, which is still lower than what it is for
non-polled mode.
I also found that things worked much better if we checked for the
actually STOP detection bit to come instead of looking at the activity
bit in the status register.
Also tested on my Asus x205ta, which has an i2c keyboard.
ok?
Index: dwiic.c
===================================================================
RCS file: /cvs/src/sys/dev/ic/dwiic.c,v
retrieving revision 1.6
diff -u -p -r1.6 dwiic.c
--- dwiic.c 6 Aug 2019 06:56:29 -0000 1.6
+++ dwiic.c 17 Aug 2019 16:12:39 -0000
@@ -350,7 +350,7 @@ dwiic_i2c_exec(void *cookie, i2c_op_t op
sc->sc_dev.dv_xname, __func__, tx_limit, x));
if (flags & I2C_F_POLL) {
- for (retries = 100; retries > 0; retries--) {
+ for (retries = 1000; retries > 0; retries--) {
rx_avail = dwiic_read(sc, DW_IC_RXFLR);
if (rx_avail > 0)
break;
@@ -407,14 +407,13 @@ dwiic_i2c_exec(void *cookie, i2c_op_t op
if (I2C_OP_STOP_P(op) && I2C_OP_WRITE_P(op)) {
if (flags & I2C_F_POLL) {
- /* wait for bus to be idle */
for (retries = 100; retries > 0; retries--) {
- st = dwiic_read(sc, DW_IC_STATUS);
- if (!(st & DW_IC_STATUS_ACTIVITY))
+ st = dwiic_read(sc, DW_IC_RAW_INTR_STAT);
+ if (st & DW_IC_INTR_STOP_DET)
break;
DELAY(1000);
}
- if (st & DW_IC_STATUS_ACTIVITY)
+ if (!(st & DW_IC_INTR_STOP_DET))
printf("%s: timed out waiting for bus idle\n",
sc->sc_dev.dv_xname);
} else {
