usb: typec: ucsi_acpi: Remove Dell quirk

The Dell quirk from ucsi_acpi.c. The quirk is no longer
necessary as we no longer send lone connector change acks.
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240327224554.1772525-4-lk@c--e.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/ucsi/ucsi_acpi.c

@@ -23,7 +23,6 @@ struct ucsi_acpi {
 	void *base;
 	struct completion complete;
 	unsigned long flags;
-#define UCSI_ACPI_SUPPRESS_EVENT	0
 #define UCSI_ACPI_COMMAND_PENDING	1
 #define UCSI_ACPI_ACK_PENDING		2
 	guid_t guid;
@@ -129,49 +128,6 @@ static const struct ucsi_operations ucsi_zenbook_ops = {
 	.async_write = ucsi_acpi_async_write
 };
 
-/*
- * Some Dell laptops don't like ACK commands with the
- * UCSI_ACK_CONNECTOR_CHANGE but not the UCSI_ACK_COMMAND_COMPLETE
- * bit set. To work around this send a dummy command and bundle the
- * UCSI_ACK_CONNECTOR_CHANGE with the UCSI_ACK_COMMAND_COMPLETE
- * for the dummy command.
- */
-static int
-ucsi_dell_sync_write(struct ucsi *ucsi, unsigned int offset,
-		     const void *val, size_t val_len)
-{
-	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
-	u64 cmd = *(u64 *)val;
-	u64 dummycmd = UCSI_GET_CAPABILITY;
-	int ret;
-
-	if (cmd == (UCSI_ACK_CC_CI | UCSI_ACK_CONNECTOR_CHANGE)) {
-		cmd |= UCSI_ACK_COMMAND_COMPLETE;
-
-		/*
-		 * The UCSI core thinks it is sending a connector change ack
-		 * and will accept new connector change events. We don't want
-		 * this to happen for the dummy command as its response will
-		 * still report the very event that the core is trying to clear.
-		 */
-		set_bit(UCSI_ACPI_SUPPRESS_EVENT, &ua->flags);
-		ret = ucsi_acpi_sync_write(ucsi, UCSI_CONTROL, &dummycmd,
-					   sizeof(dummycmd));
-		clear_bit(UCSI_ACPI_SUPPRESS_EVENT, &ua->flags);
-
-		if (ret < 0)
-			return ret;
-	}
-
-	return ucsi_acpi_sync_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
-}
-
-static const struct ucsi_operations ucsi_dell_ops = {
-	.read = ucsi_acpi_read,
-	.sync_write = ucsi_dell_sync_write,
-	.async_write = ucsi_acpi_async_write
-};
-
 static const struct dmi_system_id ucsi_acpi_quirks[] = {
 	{
 		.matches = {
@@ -180,12 +136,6 @@ static const struct dmi_system_id ucsi_acpi_quirks[] = {
 		},
 		.driver_data = (void *)&ucsi_zenbook_ops,
 	},
-	{
-		.matches = {
-			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		},
-		.driver_data = (void *)&ucsi_dell_ops,
-	},
 	{ }
 };
 
@@ -199,8 +149,7 @@ static void ucsi_acpi_notify(acpi_handle handle, u32 event, void *data)
 	if (ret)
 		return;
 
-	if (UCSI_CCI_CONNECTOR(cci) &&
-	    !test_bit(UCSI_ACPI_SUPPRESS_EVENT, &ua->flags))
+	if (UCSI_CCI_CONNECTOR(cci))
 		ucsi_connector_change(ua->ucsi, UCSI_CCI_CONNECTOR(cci));
 
 	if (cci & UCSI_CCI_ACK_COMPLETE &&