Commit 9e3caa9d authored by Diogo Ivo's avatar Diogo Ivo Committed by Greg Kroah-Hartman
Browse files

usb: typec: ucsi_acpi: Add LG Gram quirk 



Some LG Gram laptops report a bogus connector change event after a
GET_PDOS command for the partner's source PDOs, which disappears from
the CCI after acknowledging the command. However, the subsequent
GET_CONNECTOR_STATUS in ucsi_handle_connector_change() still reports
this bogus change in bits 5 and 6, leading to the UCSI core re-checking
the partner's source PDOs and thus to an infinite loop.

Fix this by adding a quirk that signals when a potentially buggy GET_PDOS
command is used, checks the status change report and clears it if it is a
bogus event before sending it to the UCSI core.

Signed-off-by: default avatarDiogo Ivo <diogo.ivo@tecnico.ulisboa.pt>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240612-gram_quirk-v1-1-52b0ff0e1546@tecnico.ulisboa.pt


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8e1ec117

drivers/usb/typec/ucsi/ucsi_acpi.c

+61 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ struct ucsi_acpi { 
	unsigned long flags;

#define UCSI_ACPI_COMMAND_PENDING	1

#define UCSI_ACPI_ACK_PENDING		2

#define UCSI_ACPI_CHECK_BOGUS_EVENT	3

	guid_t guid;

	u64 cmd;

};
@@ -128,6 +129,58 @@ static const struct ucsi_operations ucsi_zenbook_ops = { 
	.async_write = ucsi_acpi_async_write

};



static int ucsi_gram_read(struct ucsi *ucsi, unsigned int offset,

			  void *val, size_t val_len)

{

	u16 bogus_change = UCSI_CONSTAT_POWER_LEVEL_CHANGE |

			   UCSI_CONSTAT_PDOS_CHANGE;

	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);

	struct ucsi_connector_status *status;

	int ret;



	ret = ucsi_acpi_read(ucsi, offset, val, val_len);

	if (ret < 0)

		return ret;



	if (UCSI_COMMAND(ua->cmd) == UCSI_GET_CONNECTOR_STATUS &&

	    test_bit(UCSI_ACPI_CHECK_BOGUS_EVENT, &ua->flags) &&

	    offset == UCSI_MESSAGE_IN) {

		status = (struct ucsi_connector_status *)val;



		/* Clear the bogus change */

		if (status->change == bogus_change)

			status->change = 0;



		clear_bit(UCSI_ACPI_CHECK_BOGUS_EVENT, &ua->flags);

	}



	return ret;

}



static int ucsi_gram_sync_write(struct ucsi *ucsi, unsigned int offset,

				const void *val, size_t val_len)

{

	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);

	int ret;



	ret = ucsi_acpi_sync_write(ucsi, offset, val, val_len);

	if (ret < 0)

		return ret;



	if (UCSI_COMMAND(ua->cmd) == UCSI_GET_PDOS &&

	    ua->cmd & UCSI_GET_PDOS_PARTNER_PDO(1) &&

	    ua->cmd & UCSI_GET_PDOS_SRC_PDOS)

		set_bit(UCSI_ACPI_CHECK_BOGUS_EVENT, &ua->flags);



	return ret;

}



static const struct ucsi_operations ucsi_gram_ops = {

	.read = ucsi_gram_read,

	.sync_write = ucsi_gram_sync_write,

	.async_write = ucsi_acpi_async_write

};



static const struct dmi_system_id ucsi_acpi_quirks[] = {

	{

		.matches = {
@@ -136,6 +189,14 @@ static const struct dmi_system_id ucsi_acpi_quirks[] = { 
		},

		.driver_data = (void *)&ucsi_zenbook_ops,

	},

	{

		.matches = {

			DMI_MATCH(DMI_SYS_VENDOR, "LG Electronics"),

			DMI_MATCH(DMI_PRODUCT_FAMILY, "LG gram PC"),

			DMI_MATCH(DMI_PRODUCT_NAME, "90Q"),

		},

		.driver_data = (void *)&ucsi_gram_ops,

	},

	{ }

};