1de73b88cSMauro Carvalho Chehab // SPDX-License-Identifier: GPL-2.0-only 2de73b88cSMauro Carvalho Chehab /* 3de73b88cSMauro Carvalho Chehab * cec-notifier.c - notify CEC drivers of physical address changes 4de73b88cSMauro Carvalho Chehab * 5de73b88cSMauro Carvalho Chehab * Copyright 2016 Russell King <rmk+kernel@arm.linux.org.uk> 6de73b88cSMauro Carvalho Chehab * Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 7de73b88cSMauro Carvalho Chehab */ 8de73b88cSMauro Carvalho Chehab 9de73b88cSMauro Carvalho Chehab #include <linux/export.h> 10de73b88cSMauro Carvalho Chehab #include <linux/string.h> 11de73b88cSMauro Carvalho Chehab #include <linux/slab.h> 12de73b88cSMauro Carvalho Chehab #include <linux/list.h> 13de73b88cSMauro Carvalho Chehab #include <linux/kref.h> 14de73b88cSMauro Carvalho Chehab #include <linux/of_platform.h> 15de73b88cSMauro Carvalho Chehab 16de73b88cSMauro Carvalho Chehab #include <media/cec.h> 17de73b88cSMauro Carvalho Chehab #include <media/cec-notifier.h> 18de73b88cSMauro Carvalho Chehab #include <drm/drm_edid.h> 19de73b88cSMauro Carvalho Chehab 20de73b88cSMauro Carvalho Chehab struct cec_notifier { 21de73b88cSMauro Carvalho Chehab struct mutex lock; 22de73b88cSMauro Carvalho Chehab struct list_head head; 23de73b88cSMauro Carvalho Chehab struct kref kref; 24de73b88cSMauro Carvalho Chehab struct device *hdmi_dev; 25de73b88cSMauro Carvalho Chehab struct cec_connector_info conn_info; 26de73b88cSMauro Carvalho Chehab const char *port_name; 27de73b88cSMauro Carvalho Chehab struct cec_adapter *cec_adap; 28de73b88cSMauro Carvalho Chehab 29de73b88cSMauro Carvalho Chehab u16 phys_addr; 30de73b88cSMauro Carvalho Chehab }; 31de73b88cSMauro Carvalho Chehab 32de73b88cSMauro Carvalho Chehab static LIST_HEAD(cec_notifiers); 33de73b88cSMauro Carvalho Chehab static DEFINE_MUTEX(cec_notifiers_lock); 34de73b88cSMauro Carvalho Chehab 35de73b88cSMauro Carvalho Chehab /** 36de73b88cSMauro Carvalho Chehab * cec_notifier_get_conn - find or create a new cec_notifier for the given 37de73b88cSMauro Carvalho Chehab * device and connector tuple. 38de73b88cSMauro Carvalho Chehab * @hdmi_dev: device that sends the events. 39de73b88cSMauro Carvalho Chehab * @port_name: the connector name from which the event occurs 40de73b88cSMauro Carvalho Chehab * 41de73b88cSMauro Carvalho Chehab * If a notifier for device @dev already exists, then increase the refcount 42de73b88cSMauro Carvalho Chehab * and return that notifier. 43de73b88cSMauro Carvalho Chehab * 44de73b88cSMauro Carvalho Chehab * If it doesn't exist, then allocate a new notifier struct and return a 45de73b88cSMauro Carvalho Chehab * pointer to that new struct. 46de73b88cSMauro Carvalho Chehab * 47de73b88cSMauro Carvalho Chehab * Return NULL if the memory could not be allocated. 48de73b88cSMauro Carvalho Chehab */ 49de73b88cSMauro Carvalho Chehab static struct cec_notifier * 50de73b88cSMauro Carvalho Chehab cec_notifier_get_conn(struct device *hdmi_dev, const char *port_name) 51de73b88cSMauro Carvalho Chehab { 52de73b88cSMauro Carvalho Chehab struct cec_notifier *n; 53de73b88cSMauro Carvalho Chehab 54de73b88cSMauro Carvalho Chehab mutex_lock(&cec_notifiers_lock); 55de73b88cSMauro Carvalho Chehab list_for_each_entry(n, &cec_notifiers, head) { 56de73b88cSMauro Carvalho Chehab if (n->hdmi_dev == hdmi_dev && 57de73b88cSMauro Carvalho Chehab (!port_name || 58de73b88cSMauro Carvalho Chehab (n->port_name && !strcmp(n->port_name, port_name)))) { 59de73b88cSMauro Carvalho Chehab kref_get(&n->kref); 60de73b88cSMauro Carvalho Chehab mutex_unlock(&cec_notifiers_lock); 61de73b88cSMauro Carvalho Chehab return n; 62de73b88cSMauro Carvalho Chehab } 63de73b88cSMauro Carvalho Chehab } 64de73b88cSMauro Carvalho Chehab n = kzalloc(sizeof(*n), GFP_KERNEL); 65de73b88cSMauro Carvalho Chehab if (!n) 66de73b88cSMauro Carvalho Chehab goto unlock; 67de73b88cSMauro Carvalho Chehab n->hdmi_dev = hdmi_dev; 68de73b88cSMauro Carvalho Chehab if (port_name) { 69de73b88cSMauro Carvalho Chehab n->port_name = kstrdup(port_name, GFP_KERNEL); 70de73b88cSMauro Carvalho Chehab if (!n->port_name) { 71de73b88cSMauro Carvalho Chehab kfree(n); 72de73b88cSMauro Carvalho Chehab n = NULL; 73de73b88cSMauro Carvalho Chehab goto unlock; 74de73b88cSMauro Carvalho Chehab } 75de73b88cSMauro Carvalho Chehab } 76de73b88cSMauro Carvalho Chehab n->phys_addr = CEC_PHYS_ADDR_INVALID; 77de73b88cSMauro Carvalho Chehab 78de73b88cSMauro Carvalho Chehab mutex_init(&n->lock); 79de73b88cSMauro Carvalho Chehab kref_init(&n->kref); 80de73b88cSMauro Carvalho Chehab list_add_tail(&n->head, &cec_notifiers); 81de73b88cSMauro Carvalho Chehab unlock: 82de73b88cSMauro Carvalho Chehab mutex_unlock(&cec_notifiers_lock); 83de73b88cSMauro Carvalho Chehab return n; 84de73b88cSMauro Carvalho Chehab } 85de73b88cSMauro Carvalho Chehab 86de73b88cSMauro Carvalho Chehab static void cec_notifier_release(struct kref *kref) 87de73b88cSMauro Carvalho Chehab { 88de73b88cSMauro Carvalho Chehab struct cec_notifier *n = 89de73b88cSMauro Carvalho Chehab container_of(kref, struct cec_notifier, kref); 90de73b88cSMauro Carvalho Chehab 91de73b88cSMauro Carvalho Chehab list_del(&n->head); 92de73b88cSMauro Carvalho Chehab kfree(n->port_name); 93de73b88cSMauro Carvalho Chehab kfree(n); 94de73b88cSMauro Carvalho Chehab } 95de73b88cSMauro Carvalho Chehab 96de73b88cSMauro Carvalho Chehab static void cec_notifier_put(struct cec_notifier *n) 97de73b88cSMauro Carvalho Chehab { 98de73b88cSMauro Carvalho Chehab mutex_lock(&cec_notifiers_lock); 99de73b88cSMauro Carvalho Chehab kref_put(&n->kref, cec_notifier_release); 100de73b88cSMauro Carvalho Chehab mutex_unlock(&cec_notifiers_lock); 101de73b88cSMauro Carvalho Chehab } 102de73b88cSMauro Carvalho Chehab 103de73b88cSMauro Carvalho Chehab struct cec_notifier * 104de73b88cSMauro Carvalho Chehab cec_notifier_conn_register(struct device *hdmi_dev, const char *port_name, 105de73b88cSMauro Carvalho Chehab const struct cec_connector_info *conn_info) 106de73b88cSMauro Carvalho Chehab { 107de73b88cSMauro Carvalho Chehab struct cec_notifier *n = cec_notifier_get_conn(hdmi_dev, port_name); 108de73b88cSMauro Carvalho Chehab 109de73b88cSMauro Carvalho Chehab if (!n) 110de73b88cSMauro Carvalho Chehab return n; 111de73b88cSMauro Carvalho Chehab 112de73b88cSMauro Carvalho Chehab mutex_lock(&n->lock); 113de73b88cSMauro Carvalho Chehab n->phys_addr = CEC_PHYS_ADDR_INVALID; 114de73b88cSMauro Carvalho Chehab if (conn_info) 115de73b88cSMauro Carvalho Chehab n->conn_info = *conn_info; 116de73b88cSMauro Carvalho Chehab else 117de73b88cSMauro Carvalho Chehab memset(&n->conn_info, 0, sizeof(n->conn_info)); 118de73b88cSMauro Carvalho Chehab if (n->cec_adap) { 119de73b88cSMauro Carvalho Chehab cec_phys_addr_invalidate(n->cec_adap); 120de73b88cSMauro Carvalho Chehab cec_s_conn_info(n->cec_adap, conn_info); 121de73b88cSMauro Carvalho Chehab } 122de73b88cSMauro Carvalho Chehab mutex_unlock(&n->lock); 123de73b88cSMauro Carvalho Chehab return n; 124de73b88cSMauro Carvalho Chehab } 125de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_conn_register); 126de73b88cSMauro Carvalho Chehab 127de73b88cSMauro Carvalho Chehab void cec_notifier_conn_unregister(struct cec_notifier *n) 128de73b88cSMauro Carvalho Chehab { 129de73b88cSMauro Carvalho Chehab if (!n) 130de73b88cSMauro Carvalho Chehab return; 131de73b88cSMauro Carvalho Chehab 132de73b88cSMauro Carvalho Chehab mutex_lock(&n->lock); 133de73b88cSMauro Carvalho Chehab memset(&n->conn_info, 0, sizeof(n->conn_info)); 134de73b88cSMauro Carvalho Chehab n->phys_addr = CEC_PHYS_ADDR_INVALID; 135de73b88cSMauro Carvalho Chehab if (n->cec_adap) { 136de73b88cSMauro Carvalho Chehab cec_phys_addr_invalidate(n->cec_adap); 137de73b88cSMauro Carvalho Chehab cec_s_conn_info(n->cec_adap, NULL); 138de73b88cSMauro Carvalho Chehab } 139de73b88cSMauro Carvalho Chehab mutex_unlock(&n->lock); 140de73b88cSMauro Carvalho Chehab cec_notifier_put(n); 141de73b88cSMauro Carvalho Chehab } 142de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_conn_unregister); 143de73b88cSMauro Carvalho Chehab 144de73b88cSMauro Carvalho Chehab struct cec_notifier * 145de73b88cSMauro Carvalho Chehab cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *port_name, 146de73b88cSMauro Carvalho Chehab struct cec_adapter *adap) 147de73b88cSMauro Carvalho Chehab { 148de73b88cSMauro Carvalho Chehab struct cec_notifier *n; 149de73b88cSMauro Carvalho Chehab 150de73b88cSMauro Carvalho Chehab if (WARN_ON(!adap)) 151de73b88cSMauro Carvalho Chehab return NULL; 152de73b88cSMauro Carvalho Chehab 153de73b88cSMauro Carvalho Chehab n = cec_notifier_get_conn(hdmi_dev, port_name); 154de73b88cSMauro Carvalho Chehab if (!n) 155de73b88cSMauro Carvalho Chehab return n; 156de73b88cSMauro Carvalho Chehab 157de73b88cSMauro Carvalho Chehab mutex_lock(&n->lock); 158de73b88cSMauro Carvalho Chehab n->cec_adap = adap; 159de73b88cSMauro Carvalho Chehab adap->conn_info = n->conn_info; 160de73b88cSMauro Carvalho Chehab adap->notifier = n; 161de73b88cSMauro Carvalho Chehab cec_s_phys_addr(adap, n->phys_addr, false); 162de73b88cSMauro Carvalho Chehab mutex_unlock(&n->lock); 163de73b88cSMauro Carvalho Chehab return n; 164de73b88cSMauro Carvalho Chehab } 165de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_cec_adap_register); 166de73b88cSMauro Carvalho Chehab 167de73b88cSMauro Carvalho Chehab void cec_notifier_cec_adap_unregister(struct cec_notifier *n, 168de73b88cSMauro Carvalho Chehab struct cec_adapter *adap) 169de73b88cSMauro Carvalho Chehab { 170de73b88cSMauro Carvalho Chehab if (!n) 171de73b88cSMauro Carvalho Chehab return; 172de73b88cSMauro Carvalho Chehab 173de73b88cSMauro Carvalho Chehab mutex_lock(&n->lock); 174de73b88cSMauro Carvalho Chehab adap->notifier = NULL; 175de73b88cSMauro Carvalho Chehab n->cec_adap = NULL; 176de73b88cSMauro Carvalho Chehab mutex_unlock(&n->lock); 177de73b88cSMauro Carvalho Chehab cec_notifier_put(n); 178de73b88cSMauro Carvalho Chehab } 179de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_cec_adap_unregister); 180de73b88cSMauro Carvalho Chehab 181de73b88cSMauro Carvalho Chehab void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa) 182de73b88cSMauro Carvalho Chehab { 183de73b88cSMauro Carvalho Chehab if (n == NULL) 184de73b88cSMauro Carvalho Chehab return; 185de73b88cSMauro Carvalho Chehab 186de73b88cSMauro Carvalho Chehab mutex_lock(&n->lock); 187de73b88cSMauro Carvalho Chehab n->phys_addr = pa; 188de73b88cSMauro Carvalho Chehab if (n->cec_adap) 189de73b88cSMauro Carvalho Chehab cec_s_phys_addr(n->cec_adap, n->phys_addr, false); 190de73b88cSMauro Carvalho Chehab mutex_unlock(&n->lock); 191de73b88cSMauro Carvalho Chehab } 192de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_set_phys_addr); 193de73b88cSMauro Carvalho Chehab 194de73b88cSMauro Carvalho Chehab void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n, 195de73b88cSMauro Carvalho Chehab const struct edid *edid) 196de73b88cSMauro Carvalho Chehab { 197de73b88cSMauro Carvalho Chehab u16 pa = CEC_PHYS_ADDR_INVALID; 198de73b88cSMauro Carvalho Chehab 199de73b88cSMauro Carvalho Chehab if (n == NULL) 200de73b88cSMauro Carvalho Chehab return; 201de73b88cSMauro Carvalho Chehab 202de73b88cSMauro Carvalho Chehab if (edid && edid->extensions) 203de73b88cSMauro Carvalho Chehab pa = cec_get_edid_phys_addr((const u8 *)edid, 204de73b88cSMauro Carvalho Chehab EDID_LENGTH * (edid->extensions + 1), NULL); 205de73b88cSMauro Carvalho Chehab cec_notifier_set_phys_addr(n, pa); 206de73b88cSMauro Carvalho Chehab } 207de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_set_phys_addr_from_edid); 208de73b88cSMauro Carvalho Chehab 209de73b88cSMauro Carvalho Chehab struct device *cec_notifier_parse_hdmi_phandle(struct device *dev) 210de73b88cSMauro Carvalho Chehab { 211de73b88cSMauro Carvalho Chehab struct platform_device *hdmi_pdev; 212de73b88cSMauro Carvalho Chehab struct device *hdmi_dev = NULL; 213de73b88cSMauro Carvalho Chehab struct device_node *np; 214de73b88cSMauro Carvalho Chehab 215de73b88cSMauro Carvalho Chehab np = of_parse_phandle(dev->of_node, "hdmi-phandle", 0); 216de73b88cSMauro Carvalho Chehab 217de73b88cSMauro Carvalho Chehab if (!np) { 218de73b88cSMauro Carvalho Chehab dev_err(dev, "Failed to find HDMI node in device tree\n"); 219de73b88cSMauro Carvalho Chehab return ERR_PTR(-ENODEV); 220de73b88cSMauro Carvalho Chehab } 221de73b88cSMauro Carvalho Chehab hdmi_pdev = of_find_device_by_node(np); 222de73b88cSMauro Carvalho Chehab of_node_put(np); 223de73b88cSMauro Carvalho Chehab if (hdmi_pdev) { 224de73b88cSMauro Carvalho Chehab hdmi_dev = &hdmi_pdev->dev; 225de73b88cSMauro Carvalho Chehab /* 226de73b88cSMauro Carvalho Chehab * Note that the device struct is only used as a key into the 227de73b88cSMauro Carvalho Chehab * cec_notifiers list, it is never actually accessed. 228de73b88cSMauro Carvalho Chehab * So we decrement the reference here so we don't leak 229de73b88cSMauro Carvalho Chehab * memory. 230de73b88cSMauro Carvalho Chehab */ 231de73b88cSMauro Carvalho Chehab put_device(hdmi_dev); 232de73b88cSMauro Carvalho Chehab return hdmi_dev; 233de73b88cSMauro Carvalho Chehab } 234de73b88cSMauro Carvalho Chehab return ERR_PTR(-EPROBE_DEFER); 235de73b88cSMauro Carvalho Chehab } 236de73b88cSMauro Carvalho Chehab EXPORT_SYMBOL_GPL(cec_notifier_parse_hdmi_phandle); 237