Author: avg Date: Mon Sep 7 06:32:03 2020 New Revision: 365397 URL: https://svnweb.freebsd.org/changeset/base/365397
Log: twsi: some variants clear interrupt flag by writing 0, others by writing 1 Make that distinction more explicit and regular in the code. The difference in behavior is documented in the respective datasheets. Previously, the code handled the distinction by writing the control register multiple times where at least one write was zero and another was one. This can be considered a follow-up to r363021. Reviewed by: manu MFC after: 4 weeks Differential Revision: https://reviews.freebsd.org/D26308 Modified: head/sys/dev/iicbus/twsi/a10_twsi.c head/sys/dev/iicbus/twsi/twsi.c head/sys/dev/iicbus/twsi/twsi.h Modified: head/sys/dev/iicbus/twsi/a10_twsi.c ============================================================================== --- head/sys/dev/iicbus/twsi/a10_twsi.c Mon Sep 7 06:29:41 2020 (r365396) +++ head/sys/dev/iicbus/twsi/a10_twsi.c Mon Sep 7 06:32:03 2020 (r365397) @@ -122,6 +122,10 @@ a10_twsi_attach(device_t dev) sc->reg_soft_reset = TWI_SRST; sc->need_ack = true; + + if (ofw_bus_is_compatible(dev, "allwinner,sun6i-a31-i2c") || + ofw_bus_is_compatible(dev, "allwinner,sun6i-a83t-i2c")) + sc->iflag_w1c = true; return (twsi_attach(dev)); } Modified: head/sys/dev/iicbus/twsi/twsi.c ============================================================================== --- head/sys/dev/iicbus/twsi/twsi.c Mon Sep 7 06:29:41 2020 (r365396) +++ head/sys/dev/iicbus/twsi/twsi.c Mon Sep 7 06:32:03 2020 (r365397) @@ -147,7 +147,11 @@ twsi_clear_iflg(struct twsi_softc *sc) { DELAY(1000); - twsi_control_clear(sc, TWSI_CONTROL_IFLG); + /* There are two ways of clearing IFLAG. */ + if (sc->iflag_w1c) + twsi_control_set(sc, TWSI_CONTROL_IFLG); + else + twsi_control_clear(sc, TWSI_CONTROL_IFLG); DELAY(1000); } @@ -667,13 +671,11 @@ twsi_intr(void *arg) } debugf(sc->dev, "Refresh reg_control\n"); - /* - * Fix silicon bug on > Allwinner A20 by doing a read and writing - * again to the control register + /* + * Newer Allwinner chips clear IFLG after writing 1 to it. */ - status = TWSI_READ(sc, sc->reg_status); - TWSI_WRITE(sc, sc->reg_control, - sc->control_val | TWSI_CONTROL_IFLG); + TWSI_WRITE(sc, sc->reg_control, sc->control_val | + (sc->iflag_w1c ? TWSI_CONTROL_IFLG : 0)); debugf(sc->dev, "Done with interrupts\n\n"); if (transfer_done == 1) { Modified: head/sys/dev/iicbus/twsi/twsi.h ============================================================================== --- head/sys/dev/iicbus/twsi/twsi.h Mon Sep 7 06:29:41 2020 (r365396) +++ head/sys/dev/iicbus/twsi/twsi.h Mon Sep 7 06:32:03 2020 (r365397) @@ -66,6 +66,7 @@ struct twsi_softc { int error; uint32_t control_val; bool need_ack; + bool iflag_w1c; bus_size_t reg_data; bus_size_t reg_slave_addr; _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
