Hi,
On Thu, Oct 07, 2021 at 09:15:12AM -0700, Bjorn Andersson wrote:
> The one thing that I still don't understand though is, if the typec_mux
> is used by the typec controller to inform _the_ mux about the function
> to be used, what's up with the complexity in typec_mux_match()? This is
> what lead me to believe that typec_mux was enabling/disabling individual
> altmodes, rather just flipping the physical switch at the bottom.
Ah, typec_mux_match() is a mess. I'm sorry about that. I think most of
the code in that function is not used by anybody. If I remember
correctly, all that complexity is attempting to solve some
hypothetical corner case(s). Probable a case where we have multiple
muxes per port to deal with.
I think it would probable be best to clean the function to the bare
minimum by keeping only the parts that are actually used today
(attached).
thanks,
--
heikki
diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
index c8340de0ed495..44f168c9bd9bf 100644
--- a/drivers/usb/typec/mux.c
+++ b/drivers/usb/typec/mux.c
@@ -193,56 +193,15 @@ static int mux_fwnode_match(struct device *dev, const
void *fwnode)
static void *typec_mux_match(struct fwnode_handle *fwnode, const char *id,
void *data)
{
- const struct typec_altmode_desc *desc = data;
struct device *dev;
- bool match;
- int nval;
- u16 *val;
- int ret;
- int i;
/*
- * Check has the identifier already been "consumed". If it
- * has, no need to do any extra connection identification.
+ * The connection identifier will be needed with device graph (OF
graph).
+ * Device graph is not supported by this code yet, so bailing out.
*/
- match = !id;
- if (match)
- goto find_mux;
-
- /* Accessory Mode muxes */
- if (!desc) {
- match = fwnode_property_present(fwnode, "accessory");
- if (match)
- goto find_mux;
- return NULL;
- }
-
- /* Alternate Mode muxes */
- nval = fwnode_property_count_u16(fwnode, "svid");
- if (nval <= 0)
- return NULL;
-
- val = kcalloc(nval, sizeof(*val), GFP_KERNEL);
- if (!val)
- return ERR_PTR(-ENOMEM);
-
- ret = fwnode_property_read_u16_array(fwnode, "svid", val, nval);
- if (ret < 0) {
- kfree(val);
- return ERR_PTR(ret);
- }
-
- for (i = 0; i < nval; i++) {
- match = val[i] == desc->svid;
- if (match) {
- kfree(val);
- goto find_mux;
- }
- }
- kfree(val);
- return NULL;
+ if (id)
+ return ERR_PTR(-ENOTSUPP);
-find_mux:
dev = class_find_device(&typec_mux_class, NULL, fwnode,
mux_fwnode_match);
