From b747038d9d14a2ca9e6f139a8584507d5aed8634 Mon Sep 17 00:00:00 2001 From: Heikki Krogerus Date: Tue, 11 Feb 2020 14:25:26 +0300 Subject: [PATCH] usb: typec: Make the attributes read-only when writing is not possible This affects the read-writable attribute files. Before this there was no way for the user to know is changing the value supported or not. >From now on those attribute files will be made read-only unless the underlying driver supports changing of the value. Signed-off-by: Heikki Krogerus Link: https://lore.kernel.org/r/20200211112531.86510-2-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/class.c | 65 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 63 insertions(+), 2 deletions(-) diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c index 7c44e93..a451ae1 100644 --- a/drivers/usb/typec/class.c +++ b/drivers/usb/typec/class.c @@ -432,7 +432,28 @@ static struct attribute *typec_altmode_attrs[] = { &dev_attr_vdo.attr, NULL }; -ATTRIBUTE_GROUPS(typec_altmode); + +static umode_t typec_altmode_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct typec_altmode *adev = to_typec_altmode(kobj_to_dev(kobj)); + + if (attr == &dev_attr_active.attr) + if (!adev->ops || !adev->ops->activate) + return 0444; + + return attr->mode; +} + +static struct attribute_group typec_altmode_group = { + .is_visible = typec_altmode_attr_is_visible, + .attrs = typec_altmode_attrs, +}; + +static const struct attribute_group *typec_altmode_groups[] = { + &typec_altmode_group, + NULL +}; static int altmode_id_get(struct device *dev) { @@ -1305,7 +1326,47 @@ static struct attribute *typec_attrs[] = { &dev_attr_port_type.attr, NULL, }; -ATTRIBUTE_GROUPS(typec); + +static umode_t typec_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct typec_port *port = to_typec_port(kobj_to_dev(kobj)); + + if (attr == &dev_attr_data_role.attr) { + if (port->cap->data != TYPEC_PORT_DRD || + !port->ops || !port->ops->dr_set) + return 0444; + } else if (attr == &dev_attr_power_role.attr) { + if (port->cap->type != TYPEC_PORT_DRP || + !port->cap->pd_revision || + !port->ops || !port->ops->pr_set) + return 0444; + } else if (attr == &dev_attr_vconn_source.attr) { + if (!port->cap->pd_revision || + !port->ops || !port->ops->vconn_set) + return 0444; + } else if (attr == &dev_attr_preferred_role.attr) { + if (port->cap->type != TYPEC_PORT_DRP || + !port->ops || !port->ops->try_role) + return 0444; + } else if (attr == &dev_attr_port_type.attr) { + if (port->cap->type != TYPEC_PORT_DRP || + !port->ops || !port->ops->port_type_set) + return 0444; + } + + return attr->mode; +} + +static struct attribute_group typec_group = { + .is_visible = typec_attr_is_visible, + .attrs = typec_attrs, +}; + +static const struct attribute_group *typec_groups[] = { + &typec_group, + NULL +}; static int typec_uevent(struct device *dev, struct kobj_uevent_env *env) { -- 2.7.4