usb: typec: altmodes/displayport: Add pin assignment helper

commit 582836e3cf upstream.

The code to extract a peripheral's currently supported Pin Assignments
is repeated in a couple of locations. Factor it out into a separate
function.

This will also make it easier to add fixes (we only need to update 1
location instead of 2).

Fixes: c1e5c2f0cb ("usb: typec: altmodes/displayport: correct pin assignment for UFP receptacles")
Cc: stable@vger.kernel.org
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230111020546.3384569-1-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Prashant Malani 2023-01-11 02:05:41 +00:00 committed by Greg Kroah-Hartman
parent 59f9ee3796
commit 7fb1322e7a

View file

@ -418,6 +418,18 @@ static const char * const pin_assignments[] = {
[DP_PIN_ASSIGN_F] = "F",
};
/*
* Helper function to extract a peripheral's currently supported
* Pin Assignments from its DisplayPort alternate mode state.
*/
static u8 get_current_pin_assignments(struct dp_altmode *dp)
{
if (DP_CONF_CURRENTLY(dp->data.conf) == DP_CONF_DFP_D)
return DP_CAP_UFP_D_PIN_ASSIGN(dp->alt->vdo);
else
return DP_CAP_DFP_D_PIN_ASSIGN(dp->alt->vdo);
}
static ssize_t
pin_assignment_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t size)
@ -444,10 +456,7 @@ pin_assignment_store(struct device *dev, struct device_attribute *attr,
goto out_unlock;
}
if (DP_CONF_CURRENTLY(dp->data.conf) == DP_CONF_DFP_D)
assignments = DP_CAP_UFP_D_PIN_ASSIGN(dp->alt->vdo);
else
assignments = DP_CAP_DFP_D_PIN_ASSIGN(dp->alt->vdo);
assignments = get_current_pin_assignments(dp);
if (!(DP_CONF_GET_PIN_ASSIGN(conf) & assignments)) {
ret = -EINVAL;
@ -484,10 +493,7 @@ static ssize_t pin_assignment_show(struct device *dev,
cur = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
if (DP_CONF_CURRENTLY(dp->data.conf) == DP_CONF_DFP_D)
assignments = DP_CAP_UFP_D_PIN_ASSIGN(dp->alt->vdo);
else
assignments = DP_CAP_DFP_D_PIN_ASSIGN(dp->alt->vdo);
assignments = get_current_pin_assignments(dp);
for (i = 0; assignments; assignments >>= 1, i++) {
if (assignments & 1) {