drivers/media/platform/vivid/vivid-cec.c

   1 /*
   2  * vivid-cec.c - A Virtual Video Test Driver, cec emulation
   3  *
   4  * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   5  *
   6  * This program is free software; you may redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  11  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  12  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  13  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  14  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  15  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  16  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  17  * SOFTWARE.
  18  */
  19
  20 #include <media/cec.h>
  21
  22 #include "vivid-core.h"
  23 #include "vivid-cec.h"
  24
  25 void vivid_cec_bus_free_work(struct vivid_dev *dev)
  26 {
  27         spin_lock(&dev->cec_slock);
  28         while (!list_empty(&dev->cec_work_list)) {
  29                 struct vivid_cec_work *cw =
  30                         list_first_entry(&dev->cec_work_list,
  31                                          struct vivid_cec_work, list);
  32
  33                 spin_unlock(&dev->cec_slock);
  34                 cancel_delayed_work_sync(&cw->work);
  35                 spin_lock(&dev->cec_slock);
  36                 list_del(&cw->list);
  37                 cec_transmit_done(cw->adap, CEC_TX_STATUS_LOW_DRIVE, 0, 0, 1, 0);
  38                 kfree(cw);
  39         }
  40         spin_unlock(&dev->cec_slock);
  41 }
  42
  43 static bool vivid_cec_find_dest_adap(struct vivid_dev *dev,
  44                                      struct cec_adapter *adap, u8 dest)
  45 {
  46         unsigned int i;
  47
  48         if (dest >= 0xf)
  49                 return false;
  50
  51         if (adap != dev->cec_rx_adap && dev->cec_rx_adap &&
  52             dev->cec_rx_adap->is_configured &&
  53             cec_has_log_addr(dev->cec_rx_adap, dest))
  54                 return true;
  55
  56         for (i = 0; i < MAX_OUTPUTS && dev->cec_tx_adap[i]; i++) {
  57                 if (adap == dev->cec_tx_adap[i])
  58                         continue;
  59                 if (!dev->cec_tx_adap[i]->is_configured)
  60                         continue;
  61                 if (cec_has_log_addr(dev->cec_tx_adap[i], dest))
  62                         return true;
  63         }
  64         return false;
  65 }
  66
  67 static void vivid_cec_xfer_done_worker(struct work_struct *work)
  68 {
  69         struct vivid_cec_work *cw =
  70                 container_of(work, struct vivid_cec_work, work.work);
  71         struct vivid_dev *dev = cw->dev;
  72         struct cec_adapter *adap = cw->adap;
  73         u8 dest = cec_msg_destination(&cw->msg);
  74         bool valid_dest;
  75         unsigned int i;
  76
  77         valid_dest = cec_msg_is_broadcast(&cw->msg);
  78         if (!valid_dest)
  79                 valid_dest = vivid_cec_find_dest_adap(dev, adap, dest);
  80
  81         cw->tx_status = valid_dest ? CEC_TX_STATUS_OK : CEC_TX_STATUS_NACK;
  82         spin_lock(&dev->cec_slock);
  83         dev->cec_xfer_time_jiffies = 0;
  84         dev->cec_xfer_start_jiffies = 0;
  85         list_del(&cw->list);
  86         spin_unlock(&dev->cec_slock);
  87         cec_transmit_done(cw->adap, cw->tx_status, 0, valid_dest ? 0 : 1, 0, 0);
  88
  89         /* Broadcast message */
  90         if (adap != dev->cec_rx_adap)
  91                 cec_received_msg(dev->cec_rx_adap, &cw->msg);
  92         for (i = 0; i < MAX_OUTPUTS && dev->cec_tx_adap[i]; i++)
  93                 if (adap != dev->cec_tx_adap[i])
  94                         cec_received_msg(dev->cec_tx_adap[i], &cw->msg);
  95         kfree(cw);
  96 }
  97
  98 static void vivid_cec_xfer_try_worker(struct work_struct *work)
  99 {
 100         struct vivid_cec_work *cw =
 101                 container_of(work, struct vivid_cec_work, work.work);
 102         struct vivid_dev *dev = cw->dev;
 103
 104         spin_lock(&dev->cec_slock);
 105         if (dev->cec_xfer_time_jiffies) {
 106                 list_del(&cw->list);
 107                 spin_unlock(&dev->cec_slock);
 108                 cec_transmit_done(cw->adap, CEC_TX_STATUS_ARB_LOST, 1, 0, 0, 0);
 109                 kfree(cw);
 110         } else {
 111                 INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_done_worker);
 112                 dev->cec_xfer_start_jiffies = jiffies;
 113                 dev->cec_xfer_time_jiffies = usecs_to_jiffies(cw->usecs);
 114                 spin_unlock(&dev->cec_slock);
 115                 schedule_delayed_work(&cw->work, dev->cec_xfer_time_jiffies);
 116         }
 117 }
 118
 119 static int vivid_cec_adap_enable(struct cec_adapter *adap, bool enable)
 120 {
 121         return 0;
 122 }
 123
 124 static int vivid_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
 125 {
 126         return 0;
 127 }
 128
 129 /*
 130  * One data bit takes 2400 us, each byte needs 10 bits so that's 24000 us
 131  * per byte.
 132  */
 133 #define USECS_PER_BYTE 24000
 134
 135 static int vivid_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
 136                                    u32 signal_free_time, struct cec_msg *msg)
 137 {
 138         struct vivid_dev *dev = adap->priv;
 139         struct vivid_cec_work *cw = kzalloc(sizeof(*cw), GFP_KERNEL);
 140         long delta_jiffies = 0;
 141
 142         if (cw == NULL)
 143                 return -ENOMEM;
 144         cw->dev = dev;
 145         cw->adap = adap;
 146         cw->usecs = CEC_FREE_TIME_TO_USEC(signal_free_time) +
 147                     msg->len * USECS_PER_BYTE;
 148         cw->msg = *msg;
 149
 150         spin_lock(&dev->cec_slock);
 151         list_add(&cw->list, &dev->cec_work_list);
 152         if (dev->cec_xfer_time_jiffies == 0) {
 153                 INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_done_worker);
 154                 dev->cec_xfer_start_jiffies = jiffies;
 155                 dev->cec_xfer_time_jiffies = usecs_to_jiffies(cw->usecs);
 156                 delta_jiffies = dev->cec_xfer_time_jiffies;
 157         } else {
 158                 INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_try_worker);
 159                 delta_jiffies = dev->cec_xfer_start_jiffies +
 160                         dev->cec_xfer_time_jiffies - jiffies;
 161         }
 162         spin_unlock(&dev->cec_slock);
 163         schedule_delayed_work(&cw->work, delta_jiffies < 0 ? 0 : delta_jiffies);
 164         return 0;
 165 }
 166
 167 static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
 168 {
 169         struct vivid_dev *dev = adap->priv;
 170         struct cec_msg reply;
 171         u8 dest = cec_msg_destination(msg);
 172         u8 disp_ctl;
 173         char osd[14];
 174
 175         if (cec_msg_is_broadcast(msg))
 176                 dest = adap->log_addrs.log_addr[0];
 177         cec_msg_init(&reply, dest, cec_msg_initiator(msg));
 178
 179         switch (cec_msg_opcode(msg)) {
 180         case CEC_MSG_SET_OSD_STRING:
 181                 if (!cec_is_sink(adap))
 182                         return -ENOMSG;
 183                 cec_ops_set_osd_string(msg, &disp_ctl, osd);
 184                 switch (disp_ctl) {
 185                 case CEC_OP_DISP_CTL_DEFAULT:
 186                         strcpy(dev->osd, osd);
 187                         dev->osd_jiffies = jiffies;
 188                         break;
 189                 case CEC_OP_DISP_CTL_UNTIL_CLEARED:
 190                         strcpy(dev->osd, osd);
 191                         dev->osd_jiffies = 0;
 192                         break;
 193                 case CEC_OP_DISP_CTL_CLEAR:
 194                         dev->osd[0] = 0;
 195                         dev->osd_jiffies = 0;
 196                         break;
 197                 default:
 198                         cec_msg_feature_abort(&reply, cec_msg_opcode(msg),
 199                                               CEC_OP_ABORT_INVALID_OP);
 200                         cec_transmit_msg(adap, &reply, false);
 201                         break;
 202                 }
 203                 break;
 204         default:
 205                 return -ENOMSG;
 206         }
 207         return 0;
 208 }
 209
 210 static const struct cec_adap_ops vivid_cec_adap_ops = {
 211         .adap_enable = vivid_cec_adap_enable,
 212         .adap_log_addr = vivid_cec_adap_log_addr,
 213         .adap_transmit = vivid_cec_adap_transmit,
 214         .received = vivid_received,
 215 };
 216
 217 struct cec_adapter *vivid_cec_alloc_adap(struct vivid_dev *dev,
 218                                          unsigned int idx,
 219                                          bool is_source)
 220 {
 221         char name[sizeof(dev->vid_out_dev.name) + 2];
 222         u32 caps = CEC_CAP_TRANSMIT | CEC_CAP_LOG_ADDRS |
 223                 CEC_CAP_PASSTHROUGH | CEC_CAP_RC | CEC_CAP_MONITOR_ALL;
 224
 225         snprintf(name, sizeof(name), "%s%d",
 226                  is_source ? dev->vid_out_dev.name : dev->vid_cap_dev.name,
 227                  idx);
 228         return cec_allocate_adapter(&vivid_cec_adap_ops, dev,
 229                 name, caps, 1);
 230 }