drivers/misc/ti-st/st_ll.c

   1 /*
   2  *  Shared Transport driver
   3  *      HCI-LL module responsible for TI proprietary HCI_LL protocol
   4  *  Copyright (C) 2009-2010 Texas Instruments
   5  *  Author: Pavan Savoy <pavan_savoy@ti.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #define pr_fmt(fmt) "(stll) :" fmt
  23 #include <linux/skbuff.h>
  24 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/ti_wilink_st.h>
  27
  28 /**********************************************************************/
  29
  30 /* internal functions */
  31 static void send_ll_cmd(struct st_data_s *st_data,
  32         unsigned char cmd)
  33 {
  34
  35         pr_debug("%s: writing %x", __func__, cmd);
  36         st_int_write(st_data, &cmd, 1);
  37         return;
  38 }
  39
  40 static void ll_device_want_to_sleep(struct st_data_s *st_data)
  41 {
  42         struct kim_data_s       *kim_data;
  43         struct ti_st_plat_data  *pdata;
  44
  45         pr_debug("%s", __func__);
  46         /* sanity check */
  47         if (st_data->ll_state != ST_LL_AWAKE)
  48                 pr_err("ERR hcill: ST_LL_GO_TO_SLEEP_IND"
  49                           "in state %ld", st_data->ll_state);
  50
  51         send_ll_cmd(st_data, LL_SLEEP_ACK);
  52         /* update state */
  53         st_data->ll_state = ST_LL_ASLEEP;
  54
  55         /* communicate to platform about chip asleep */
  56         kim_data = st_data->kim_data;
  57         if (kim_data->kim_pdev->dev.of_node) {
  58                 pr_debug("use device tree data");
  59                 pdata = dt_pdata;
  60         } else {
  61                 pdata = kim_data->kim_pdev->dev.platform_data;
  62         }
  63
  64         if (pdata->chip_asleep)
  65                 pdata->chip_asleep(NULL);
  66 }
  67
  68 static void ll_device_want_to_wakeup(struct st_data_s *st_data)
  69 {
  70         struct kim_data_s       *kim_data;
  71         struct ti_st_plat_data  *pdata;
  72
  73         /* diff actions in diff states */
  74         switch (st_data->ll_state) {
  75         case ST_LL_ASLEEP:
  76                 send_ll_cmd(st_data, LL_WAKE_UP_ACK);   /* send wake_ack */
  77                 break;
  78         case ST_LL_ASLEEP_TO_AWAKE:
  79                 /* duplicate wake_ind */
  80                 pr_err("duplicate wake_ind while waiting for Wake ack");
  81                 break;
  82         case ST_LL_AWAKE:
  83                 /* duplicate wake_ind */
  84                 pr_err("duplicate wake_ind already AWAKE");
  85                 break;
  86         case ST_LL_AWAKE_TO_ASLEEP:
  87                 /* duplicate wake_ind */
  88                 pr_err("duplicate wake_ind");
  89                 break;
  90         }
  91         /* update state */
  92         st_data->ll_state = ST_LL_AWAKE;
  93
  94         /* communicate to platform about chip wakeup */
  95         kim_data = st_data->kim_data;
  96         if (kim_data->kim_pdev->dev.of_node) {
  97                 pr_debug("use device tree data");
  98                 pdata = dt_pdata;
  99         } else {
 100                 pdata = kim_data->kim_pdev->dev.platform_data;
 101         }
 102
 103         if (pdata->chip_awake)
 104                 pdata->chip_awake(NULL);
 105 }
 106
 107 /**********************************************************************/
 108 /* functions invoked by ST Core */
 109
 110 /* called when ST Core wants to
 111  * enable ST LL */
 112 void st_ll_enable(struct st_data_s *ll)
 113 {
 114         ll->ll_state = ST_LL_AWAKE;
 115 }
 116
 117 /* called when ST Core /local module wants to
 118  * disable ST LL */
 119 void st_ll_disable(struct st_data_s *ll)
 120 {
 121         ll->ll_state = ST_LL_INVALID;
 122 }
 123
 124 /* called when ST Core wants to update the state */
 125 void st_ll_wakeup(struct st_data_s *ll)
 126 {
 127         if (likely(ll->ll_state != ST_LL_AWAKE)) {
 128                 send_ll_cmd(ll, LL_WAKE_UP_IND);        /* WAKE_IND */
 129                 ll->ll_state = ST_LL_ASLEEP_TO_AWAKE;
 130         } else {
 131                 /* don't send the duplicate wake_indication */
 132                 pr_err(" Chip already AWAKE ");
 133         }
 134 }
 135
 136 /* called when ST Core wants the state */
 137 unsigned long st_ll_getstate(struct st_data_s *ll)
 138 {
 139         pr_debug(" returning state %ld", ll->ll_state);
 140         return ll->ll_state;
 141 }
 142
 143 /* called from ST Core, when a PM related packet arrives */
 144 unsigned long st_ll_sleep_state(struct st_data_s *st_data,
 145         unsigned char cmd)
 146 {
 147         switch (cmd) {
 148         case LL_SLEEP_IND:      /* sleep ind */
 149                 pr_debug("sleep indication recvd");
 150                 ll_device_want_to_sleep(st_data);
 151                 break;
 152         case LL_SLEEP_ACK:      /* sleep ack */
 153                 pr_err("sleep ack rcvd: host shouldn't");
 154                 break;
 155         case LL_WAKE_UP_IND:    /* wake ind */
 156                 pr_debug("wake indication recvd");
 157                 ll_device_want_to_wakeup(st_data);
 158                 break;
 159         case LL_WAKE_UP_ACK:    /* wake ack */
 160                 pr_debug("wake ack rcvd");
 161                 st_data->ll_state = ST_LL_AWAKE;
 162                 break;
 163         default:
 164                 pr_err(" unknown input/state ");
 165                 return -EINVAL;
 166         }
 167         return 0;
 168 }
 169
 170 /* Called from ST CORE to initialize ST LL */
 171 long st_ll_init(struct st_data_s *ll)
 172 {
 173         /* set state to invalid */
 174         ll->ll_state = ST_LL_INVALID;
 175         return 0;
 176 }
 177
 178 /* Called from ST CORE to de-initialize ST LL */
 179 long st_ll_deinit(struct st_data_s *ll)
 180 {
 181         return 0;
 182 }