On Mon, Nov 08, 2021 at 11:28:32AM +0100, Ondrej Jirman wrote:
> The code that enables either BC_LVL or COMP_CHNG interrupt in tcpm_set_cc
> wrongly assumes that the interrupt is unmasked by writing 1 to the apropriate
> bit in the mask register. In fact, interrupts are enabled when the mask
> is 0, so the tcpm_set_cc enables interrupt for COMP_CHNG when it expects
> BC_LVL interrupt to be enabled.
>
> This causes inability of the driver to recognize cable unplug events
> in host mode (unplug is recognized only via a COMP_CHNG interrupt).
>
> In device mode this bug was masked by simultaneous triggering of the VBUS
> change interrupt, because of loss of VBUS when the port peer is providing
> power.
>
> Fixes: 48242e30532b ("usb: typec: fusb302: Revert "Resolve fixed power role contract setup"")
> Signed-off-by: Ondrej Jirman <megous@xxxxxxxxxx>
> Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
Should this go to stable?
Acked-by: Heikki Krogerus@xxxxxxxxxxxxxxx
> ---
> drivers/usb/typec/tcpm/fusb302.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/fusb302.c b/drivers/usb/typec/tcpm/fusb302.c
> index 7a2a17866a823..72f9001b07921 100644
> --- a/drivers/usb/typec/tcpm/fusb302.c
> +++ b/drivers/usb/typec/tcpm/fusb302.c
> @@ -669,25 +669,27 @@ static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc)
> ret = fusb302_i2c_mask_write(chip, FUSB_REG_MASK,
> FUSB_REG_MASK_BC_LVL |
> FUSB_REG_MASK_COMP_CHNG,
> - FUSB_REG_MASK_COMP_CHNG);
> + FUSB_REG_MASK_BC_LVL);
> if (ret < 0) {
> fusb302_log(chip, "cannot set SRC interrupt, ret=%d",
> ret);
> goto done;
> }
> chip->intr_comp_chng = true;
> + chip->intr_bc_lvl = false;
> break;
> case TYPEC_CC_RD:
> ret = fusb302_i2c_mask_write(chip, FUSB_REG_MASK,
> FUSB_REG_MASK_BC_LVL |
> FUSB_REG_MASK_COMP_CHNG,
> - FUSB_REG_MASK_BC_LVL);
> + FUSB_REG_MASK_COMP_CHNG);
> if (ret < 0) {
> fusb302_log(chip, "cannot set SRC interrupt, ret=%d",
> ret);
> goto done;
> }
> chip->intr_bc_lvl = true;
> + chip->intr_comp_chng = false;
> break;
> default:
> break;
thanks,
--
heikki
