When u-boot boots the board may be powering vbus, we turn off vbus in sunxi_usbc_request_resources, if we are too quick with reading vusb-detect after this we may see a residual charge and assume we've an external vusb connected even though we do not. So when we see an external vusb wait a bit and try again.
Without this when dealing with a pmic controller vbus and doing "reset" on the u-boot console the musb host will only init once every other boot, because the other boot it thinks an external vbus is present, this commit fixes this.
Signed-off-by: Hans de Goede hdegoede@redhat.com --- arch/arm/cpu/armv7/sunxi/usbc.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/arm/cpu/armv7/sunxi/usbc.c b/arch/arm/cpu/armv7/sunxi/usbc.c index 6285fa5..a0e9604 100644 --- a/arch/arm/cpu/armv7/sunxi/usbc.c +++ b/arch/arm/cpu/armv7/sunxi/usbc.c @@ -286,12 +286,23 @@ void sunxi_usbc_vbus_disable(int index) int sunxi_usbc_vbus_detect(int index) { struct sunxi_usbc_hcd *sunxi_usbc = &sunxi_usbc_hcd[index]; - int err; + int err, retries = 3;
if (sunxi_usbc->gpio_vbus_det == -1) { eprintf("Error: invalid vbus detection pin\n"); return -1; }
- return gpio_get_value(sunxi_usbc->gpio_vbus_det); + err = gpio_get_value(sunxi_usbc->gpio_vbus_det); + /* + * Vbus may have been provided by the board and just been turned of + * some milliseconds ago on reset, what we're measuring then is a + * residual charge on Vbus, sleep a bit and try again. + */ + while (err > 0 && retries--) { + mdelay(100); + err = gpio_get_value(sunxi_usbc->gpio_vbus_det); + } + + return err; }