platform/chrome: cros_typec_switch: Add event check

The Chrome EC updates Type-C status events when mux set requests from
the Application Processor (AP) are completed. Add a check to the
flow of configuring muxes to look for this status done bit, so that
the driver is aware that the mux set completed successfully or not.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Link: https://lore.kernel.org/r/20220711072333.2064341-7-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/platform/chrome/cros_typec_switch.c b/drivers/platform/chrome/cros_typec_switch.c
index b50eced..7c01957 100644 (file)
--- a/drivers/platform/chrome/cros_typec_switch.c
+++ b/drivers/platform/chrome/cros_typec_switch.c
@@ -7,6 +7,8 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/platform_data/cros_ec_commands.h>
 #include <linux/platform_data/cros_ec_proto.h>
@@ -63,6 +65,40 @@ static int cros_typec_get_mux_state(unsigned long mode, struct typec_altmode *al
        return ret;
 }
 
+static int cros_typec_send_clear_event(struct cros_typec_switch_data *sdata, int port_num,
+                                      u32 events_mask)
+{
+       struct ec_params_typec_control req = {
+               .port = port_num,
+               .command = TYPEC_CONTROL_COMMAND_CLEAR_EVENTS,
+               .clear_events_mask = events_mask,
+       };
+
+       return cros_ec_command(sdata->ec, 0, EC_CMD_TYPEC_CONTROL, &req,
+                              sizeof(req), NULL, 0);
+}
+
+static bool cros_typec_check_event(struct cros_typec_switch_data *sdata, int port_num, u32 mask)
+{
+       struct ec_response_typec_status resp;
+       struct ec_params_typec_status req = {
+               .port = port_num,
+       };
+       int ret;
+
+       ret = cros_ec_command(sdata->ec, 0, EC_CMD_TYPEC_STATUS, &req, sizeof(req),
+                             &resp, sizeof(resp));
+       if (ret < 0) {
+               dev_warn(sdata->dev, "EC_CMD_TYPEC_STATUS failed for port: %d\n", port_num);
+               return false;
+       }
+
+       if (resp.events & mask)
+               return true;
+
+       return false;
+}
+
 /*
  * The Chrome EC treats both mode-switches and retimers as "muxes" for the purposes of the
  * host command API. This common function configures and verifies the retimer/mode-switch
@@ -71,12 +107,44 @@ static int cros_typec_get_mux_state(unsigned long mode, struct typec_altmode *al
 static int cros_typec_configure_mux(struct cros_typec_switch_data *sdata, int port_num, int index,
                                    unsigned long mode, struct typec_altmode *alt)
 {
-       int ret = cros_typec_get_mux_state(mode, alt);
+       unsigned long end;
+       u32 event_mask;
+       u8 mux_state;
+       int ret;
+
+       ret = cros_typec_get_mux_state(mode, alt);
+       if (ret < 0)
+               return ret;
+       mux_state = (u8)ret;
 
+       /* Clear any old mux set done event. */
+       if (index == 0)
+               event_mask = PD_STATUS_EVENT_MUX_0_SET_DONE;
+       else
+               event_mask = PD_STATUS_EVENT_MUX_1_SET_DONE;
+
+       ret = cros_typec_send_clear_event(sdata, port_num, event_mask);
+       if (ret < 0)
+               return ret;
+
+       /* Send the set command. */
+       ret = cros_typec_cmd_mux_set(sdata, port_num, index, mux_state);
        if (ret < 0)
                return ret;
 
-       return cros_typec_cmd_mux_set(sdata, port_num, index, (u8)ret);
+       /* Check for the mux set done event. */
+       end = jiffies + msecs_to_jiffies(1000);
+       do {
+               if (cros_typec_check_event(sdata, port_num, event_mask))
+                       return 0;
+
+               usleep_range(500, 1000);
+       } while (time_before(jiffies, end));
+
+       dev_err(sdata->dev, "Timed out waiting for mux set done on index: %d, state: %d\n",
+               index, mux_state);
+
+       return -ETIMEDOUT;
 }
 
 static int cros_typec_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)