[PATCH v2] platform/chrome: cros_ec_typec: allow deferred probe of switch handles

From: Victor Ding
Date: Tue Jan 24 2023 - 01:16:39 EST


`fwnode_typec_{retimer,mux,switch}_get()` could return `-EPROBE_DEFER`,
which is called from `cros_typec_get_switch_handles`. When this happens,
it does not indicate absence of switches; instead, it only hints that
probing of switches should occur at a later time.

Progagate `-EPROBE_DEFER` to upper layer logic so that they can re-try
probing switches as a better time.

Signed-off-by: Victor Ding <victording@xxxxxxxxxxxx>
---

Changes in v2:
- Coverted switch-block to nested if-blocks.

drivers/platform/chrome/cros_ec_typec.c | 26 ++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 59de4ce01fab..580f3bdf091c 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -145,31 +145,37 @@ static int cros_typec_get_switch_handles(struct cros_typec_port *port,
struct fwnode_handle *fwnode,
struct device *dev)
{
+ int ret = 0;
+
port->mux = fwnode_typec_mux_get(fwnode, NULL);
if (IS_ERR(port->mux)) {
- dev_dbg(dev, "Mux handle not found.\n");
+ ret = PTR_ERR(port->mux);
+ dev_dbg(dev, "Mux handle not found: %d.\n", ret);
goto mux_err;
}

port->retimer = fwnode_typec_retimer_get(fwnode);
if (IS_ERR(port->retimer)) {
- dev_dbg(dev, "Retimer handle not found.\n");
+ ret = PTR_ERR(port->retimer);
+ dev_dbg(dev, "Retimer handle not found: %d.\n", ret);
goto retimer_sw_err;
}

port->ori_sw = fwnode_typec_switch_get(fwnode);
if (IS_ERR(port->ori_sw)) {
- dev_dbg(dev, "Orientation switch handle not found.\n");
+ ret = PTR_ERR(port->ori_sw);
+ dev_dbg(dev, "Orientation switch handle not found: %d\n", ret);
goto ori_sw_err;
}

port->role_sw = fwnode_usb_role_switch_get(fwnode);
if (IS_ERR(port->role_sw)) {
- dev_dbg(dev, "USB role switch handle not found.\n");
+ ret = PTR_ERR(port->role_sw);
+ dev_dbg(dev, "USB role switch handle not found: %d\n", ret);
goto role_sw_err;
}

- return 0;
+ return ret;

role_sw_err:
typec_switch_put(port->ori_sw);
@@ -181,7 +187,7 @@ static int cros_typec_get_switch_handles(struct cros_typec_port *port,
typec_mux_put(port->mux);
port->mux = NULL;
mux_err:
- return -ENODEV;
+ return ret;
}

static int cros_typec_add_partner(struct cros_typec_data *typec, int port_num,
@@ -423,9 +429,11 @@ static int cros_typec_init_ports(struct cros_typec_data *typec)
}

ret = cros_typec_get_switch_handles(cros_port, fwnode, dev);
- if (ret)
- dev_dbg(dev, "No switch control for port %d\n",
- port_num);
+ if (ret) {
+ dev_dbg(dev, "No switch control for port %d, err: %d\n", port_num, ret);
+ if (ret == -EPROBE_DEFER)
+ goto unregister_ports;
+ }

ret = cros_typec_register_port_altmodes(typec, port_num);
if (ret) {
--
2.39.1.405.gd4c25cc71f-goog