Re: [PATCH v2 7/7] platform/chrome: cros_ec_typec: Register partner altmodes

From: Heikki Krogerus
Date: Fri Oct 30 2020 - 09:32:25 EST


On Thu, Oct 29, 2020 at 03:27:42PM -0700, Prashant Malani wrote:
> Use the discovery data from the Chrome EC to register parter altmodes
> with the Type C Connector Class framework. Also introduce a node
> struct to keep track of the list of registered alt modes.
>
> Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx>

Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
>
> Changes in v2:
> - Changed list traversal during alt mode unregistering to use
> list_for_each_entry_safe() base on review comment.
>
> drivers/platform/chrome/cros_ec_typec.c | 77 +++++++++++++++++++++++++
> 1 file changed, 77 insertions(+)
>
> diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> index f14550dac614..ce031a10eb1b 100644
> --- a/drivers/platform/chrome/cros_ec_typec.c
> +++ b/drivers/platform/chrome/cros_ec_typec.c
> @@ -7,6 +7,7 @@
> */
>
> #include <linux/acpi.h>
> +#include <linux/list.h>
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/platform_data/cros_ec_commands.h>
> @@ -31,6 +32,12 @@ enum {
> CROS_EC_ALTMODE_MAX,
> };
>
> +/* Container for altmode pointer nodes. */
> +struct cros_typec_altmode_node {
> + struct typec_altmode *amode;
> + struct list_head list;
> +};
> +
> /* Per port data. */
> struct cros_typec_port {
> struct typec_port *port;
> @@ -53,6 +60,7 @@ struct cros_typec_port {
> /* Flag indicating that PD discovery data parsing is completed. */
> bool disc_done;
> struct ec_response_typec_discovery *sop_disc;
> + struct list_head partner_mode_list;
> };
>
> /* Platform-specific data for the Chrome OS EC Type C controller. */
> @@ -172,11 +180,25 @@ static int cros_typec_add_partner(struct cros_typec_data *typec, int port_num,
> return ret;
> }
>
> +static void cros_typec_unregister_altmodes(struct cros_typec_data *typec, int port_num)
> +{
> + struct cros_typec_port *port = typec->ports[port_num];
> + struct cros_typec_altmode_node *node, *tmp;
> +
> + list_for_each_entry_safe(node, tmp, &port->partner_mode_list, list) {
> + list_del(&node->list);
> + typec_unregister_altmode(node->amode);
> + devm_kfree(typec->dev, node);
> + }
> +}
> +
> static void cros_typec_remove_partner(struct cros_typec_data *typec,
> int port_num)
> {
> struct cros_typec_port *port = typec->ports[port_num];
>
> + cros_typec_unregister_altmodes(typec, port_num);
> +
> port->state.alt = NULL;
> port->state.mode = TYPEC_STATE_USB;
> port->state.data = NULL;
> @@ -306,6 +328,8 @@ static int cros_typec_init_ports(struct cros_typec_data *typec)
> ret = -ENOMEM;
> goto unregister_ports;
> }
> +
> + INIT_LIST_HEAD(&cros_port->partner_mode_list);
> }
>
> return 0;
> @@ -590,6 +614,49 @@ static int cros_typec_get_mux_info(struct cros_typec_data *typec, int port_num,
> sizeof(req), resp, sizeof(*resp));
> }
>
> +static int cros_typec_register_altmodes(struct cros_typec_data *typec, int port_num)
> +{
> + struct cros_typec_port *port = typec->ports[port_num];
> + struct ec_response_typec_discovery *sop_disc = port->sop_disc;
> + struct cros_typec_altmode_node *node;
> + struct typec_altmode_desc desc;
> + struct typec_altmode *amode;
> + int ret = 0;
> + int i, j;
> +
> + for (i = 0; i < sop_disc->svid_count; i++) {
> + for (j = 0; j < sop_disc->svids[i].mode_count; j++) {
> + memset(&desc, 0, sizeof(desc));
> + desc.svid = sop_disc->svids[i].svid;
> + desc.mode = j;
> + desc.vdo = sop_disc->svids[i].mode_vdo[j];
> +
> + amode = typec_partner_register_altmode(port->partner, &desc);
> + if (IS_ERR(amode)) {
> + ret = PTR_ERR(amode);
> + goto err_cleanup;
> + }
> +
> + /* If no memory is available we should unregister and exit. */
> + node = devm_kzalloc(typec->dev, sizeof(*node), GFP_KERNEL);
> + if (!node) {
> + ret = -ENOMEM;
> + typec_unregister_altmode(amode);
> + goto err_cleanup;
> + }
> +
> + node->amode = amode;
> + list_add_tail(&node->list, &port->partner_mode_list);
> + }
> + }
> +
> + return 0;
> +
> +err_cleanup:
> + cros_typec_unregister_altmodes(typec, port_num);
> + return ret;
> +}
> +
> static int cros_typec_handle_sop_disc(struct cros_typec_data *typec, int port_num)
> {
> struct cros_typec_port *port = typec->ports[port_num];
> @@ -630,6 +697,16 @@ static int cros_typec_handle_sop_disc(struct cros_typec_data *typec, int port_nu
> port->p_identity.vdo[i - 3] = sop_disc->discovery_vdo[i];
>
> ret = typec_partner_set_identity(port->partner);
> + if (ret < 0) {
> + dev_err(typec->dev, "Failed to update partner PD identity, port: %d\n", port_num);
> + goto disc_exit;
> + }
> +
> + ret = cros_typec_register_altmodes(typec, port_num);
> + if (ret < 0) {
> + dev_err(typec->dev, "Failed to register partner altmodes, port: %d\n", port_num);
> + goto disc_exit;
> + }
>
> disc_exit:
> return ret;
> --
> 2.29.1.341.ge80a0c044ae-goog

thanks,

--
heikki