sound/hda/hdac_bus.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * HD-audio core bus driver
   4  */
   5
   6 #include <linux/init.h>
   7 #include <linux/io.h>
   8 #include <linux/device.h>
   9 #include <linux/module.h>
  10 #include <linux/export.h>
  11 #include <sound/hdaudio.h>
  12 #include "local.h"
  13 #include "trace.h"
  14
  15 static void snd_hdac_bus_process_unsol_events(struct work_struct *work);
  16
  17 static const struct hdac_bus_ops default_ops = {
  18         .command = snd_hdac_bus_send_cmd,
  19         .get_response = snd_hdac_bus_get_response,
  20         .link_power = snd_hdac_bus_link_power,
  21 };
  22
  23 /**
  24  * snd_hdac_bus_init - initialize a HD-audio bas bus
  25  * @bus: the pointer to bus object
  26  * @dev: device pointer
  27  * @ops: bus verb operators
  28  *
  29  * Returns 0 if successful, or a negative error code.
  30  */
  31 int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
  32                       const struct hdac_bus_ops *ops)
  33 {
  34         memset(bus, 0, sizeof(*bus));
  35         bus->dev = dev;
  36         if (ops)
  37                 bus->ops = ops;
  38         else
  39                 bus->ops = &default_ops;
  40         bus->dma_type = SNDRV_DMA_TYPE_DEV;
  41         INIT_LIST_HEAD(&bus->stream_list);
  42         INIT_LIST_HEAD(&bus->codec_list);
  43         INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events);
  44         spin_lock_init(&bus->reg_lock);
  45         mutex_init(&bus->cmd_mutex);
  46         mutex_init(&bus->lock);
  47         INIT_LIST_HEAD(&bus->hlink_list);
  48         init_waitqueue_head(&bus->rirb_wq);
  49         bus->irq = -1;
  50
  51         /*
  52          * Default value of '8' is as per the HD audio specification (Rev 1.0a).
  53          * Following relation is used to derive STRIPE control value.
  54          *  For sample rate <= 48K:
  55          *   { ((num_channels * bits_per_sample) / number of SDOs) >= 8 }
  56          *  For sample rate > 48K:
  57          *   { ((num_channels * bits_per_sample * rate/48000) /
  58          *      number of SDOs) >= 8 }
  59          */
  60         bus->sdo_limit = 8;
  61
  62         return 0;
  63 }
  64 EXPORT_SYMBOL_GPL(snd_hdac_bus_init);
  65
  66 /**
  67  * snd_hdac_bus_exit - clean up a HD-audio bas bus
  68  * @bus: the pointer to bus object
  69  */
  70 void snd_hdac_bus_exit(struct hdac_bus *bus)
  71 {
  72         WARN_ON(!list_empty(&bus->stream_list));
  73         WARN_ON(!list_empty(&bus->codec_list));
  74         cancel_work_sync(&bus->unsol_work);
  75 }
  76 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit);
  77
  78 /**
  79  * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus
  80  * @bus: bus object
  81  * @addr: the HDAC device address
  82  * @cmd: HD-audio encoded verb
  83  * @res: pointer to store the response, NULL if performing asynchronously
  84  *
  85  * Returns 0 if successful, or a negative error code.
  86  */
  87 int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr,
  88                            unsigned int cmd, unsigned int *res)
  89 {
  90         int err;
  91
  92         mutex_lock(&bus->cmd_mutex);
  93         err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res);
  94         mutex_unlock(&bus->cmd_mutex);
  95         return err;
  96 }
  97
  98 /**
  99  * snd_hdac_bus_exec_verb_unlocked - unlocked version
 100  * @bus: bus object
 101  * @addr: the HDAC device address
 102  * @cmd: HD-audio encoded verb
 103  * @res: pointer to store the response, NULL if performing asynchronously
 104  *
 105  * Returns 0 if successful, or a negative error code.
 106  */
 107 int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr,
 108                                     unsigned int cmd, unsigned int *res)
 109 {
 110         unsigned int tmp;
 111         int err;
 112
 113         if (cmd == ~0)
 114                 return -EINVAL;
 115
 116         if (res)
 117                 *res = -1;
 118         else if (bus->sync_write)
 119                 res = &tmp;
 120         for (;;) {
 121                 trace_hda_send_cmd(bus, cmd);
 122                 err = bus->ops->command(bus, cmd);
 123                 if (err != -EAGAIN)
 124                         break;
 125                 /* process pending verbs */
 126                 err = bus->ops->get_response(bus, addr, &tmp);
 127                 if (err)
 128                         break;
 129         }
 130         if (!err && res) {
 131                 err = bus->ops->get_response(bus, addr, res);
 132                 trace_hda_get_response(bus, addr, *res);
 133         }
 134         return err;
 135 }
 136 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked);
 137
 138 /**
 139  * snd_hdac_bus_queue_event - add an unsolicited event to queue
 140  * @bus: the BUS
 141  * @res: unsolicited event (lower 32bit of RIRB entry)
 142  * @res_ex: codec addr and flags (upper 32bit or RIRB entry)
 143  *
 144  * Adds the given event to the queue.  The events are processed in
 145  * the workqueue asynchronously.  Call this function in the interrupt
 146  * hanlder when RIRB receives an unsolicited event.
 147  */
 148 void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex)
 149 {
 150         unsigned int wp;
 151
 152         if (!bus)
 153                 return;
 154
 155         trace_hda_unsol_event(bus, res, res_ex);
 156         wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE;
 157         bus->unsol_wp = wp;
 158
 159         wp <<= 1;
 160         bus->unsol_queue[wp] = res;
 161         bus->unsol_queue[wp + 1] = res_ex;
 162
 163         schedule_work(&bus->unsol_work);
 164 }
 165
 166 /*
 167  * process queued unsolicited events
 168  */
 169 static void snd_hdac_bus_process_unsol_events(struct work_struct *work)
 170 {
 171         struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work);
 172         struct hdac_device *codec;
 173         struct hdac_driver *drv;
 174         unsigned int rp, caddr, res;
 175
 176         spin_lock_irq(&bus->reg_lock);
 177         while (bus->unsol_rp != bus->unsol_wp) {
 178                 rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE;
 179                 bus->unsol_rp = rp;
 180                 rp <<= 1;
 181                 res = bus->unsol_queue[rp];
 182                 caddr = bus->unsol_queue[rp + 1];
 183                 if (!(caddr & (1 << 4))) /* no unsolicited event? */
 184                         continue;
 185                 codec = bus->caddr_tbl[caddr & 0x0f];
 186                 if (!codec || !codec->registered)
 187                         continue;
 188                 spin_unlock_irq(&bus->reg_lock);
 189                 drv = drv_to_hdac_driver(codec->dev.driver);
 190                 if (drv->unsol_event)
 191                         drv->unsol_event(codec, res);
 192                 spin_lock_irq(&bus->reg_lock);
 193         }
 194         spin_unlock_irq(&bus->reg_lock);
 195 }
 196
 197 /**
 198  * snd_hdac_bus_add_device - Add a codec to bus
 199  * @bus: HDA core bus
 200  * @codec: HDA core device to add
 201  *
 202  * Adds the given codec to the list in the bus.  The caddr_tbl array
 203  * and codec_powered bits are updated, as well.
 204  * Returns zero if success, or a negative error code.
 205  */
 206 int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec)
 207 {
 208         if (bus->caddr_tbl[codec->addr]) {
 209                 dev_err(bus->dev, "address 0x%x is already occupied\n",
 210                         codec->addr);
 211                 return -EBUSY;
 212         }
 213
 214         list_add_tail(&codec->list, &bus->codec_list);
 215         bus->caddr_tbl[codec->addr] = codec;
 216         set_bit(codec->addr, &bus->codec_powered);
 217         bus->num_codecs++;
 218         return 0;
 219 }
 220
 221 /**
 222  * snd_hdac_bus_remove_device - Remove a codec from bus
 223  * @bus: HDA core bus
 224  * @codec: HDA core device to remove
 225  */
 226 void snd_hdac_bus_remove_device(struct hdac_bus *bus,
 227                                 struct hdac_device *codec)
 228 {
 229         WARN_ON(bus != codec->bus);
 230         if (list_empty(&codec->list))
 231                 return;
 232         list_del_init(&codec->list);
 233         bus->caddr_tbl[codec->addr] = NULL;
 234         clear_bit(codec->addr, &bus->codec_powered);
 235         bus->num_codecs--;
 236         flush_work(&bus->unsol_work);
 237 }
 238
 239 #ifdef CONFIG_SND_HDA_ALIGNED_MMIO
 240 /* Helpers for aligned read/write of mmio space, for Tegra */
 241 unsigned int snd_hdac_aligned_read(void __iomem *addr, unsigned int mask)
 242 {
 243         void __iomem *aligned_addr =
 244                 (void __iomem *)((unsigned long)(addr) & ~0x3);
 245         unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
 246         unsigned int v;
 247
 248         v = readl(aligned_addr);
 249         return (v >> shift) & mask;
 250 }
 251 EXPORT_SYMBOL_GPL(snd_hdac_aligned_read);
 252
 253 void snd_hdac_aligned_write(unsigned int val, void __iomem *addr,
 254                             unsigned int mask)
 255 {
 256         void __iomem *aligned_addr =
 257                 (void __iomem *)((unsigned long)(addr) & ~0x3);
 258         unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
 259         unsigned int v;
 260
 261         v = readl(aligned_addr);
 262         v &= ~(mask << shift);
 263         v |= val << shift;
 264         writel(v, aligned_addr);
 265 }
 266 EXPORT_SYMBOL_GPL(snd_hdac_aligned_write);
 267 #endif /* CONFIG_SND_HDA_ALIGNED_MMIO */
 268
 269 void snd_hdac_codec_link_up(struct hdac_device *codec)
 270 {
 271         struct hdac_bus *bus = codec->bus;
 272
 273         if (bus->ops->link_power)
 274                 bus->ops->link_power(codec, true);
 275         else
 276                 snd_hdac_bus_link_power(codec, true);
 277 }
 278 EXPORT_SYMBOL_GPL(snd_hdac_codec_link_up);
 279
 280 void snd_hdac_codec_link_down(struct hdac_device *codec)
 281 {
 282         struct hdac_bus *bus = codec->bus;
 283
 284         if (bus->ops->link_power)
 285                 bus->ops->link_power(codec, false);
 286         else
 287                 snd_hdac_bus_link_power(codec, false);
 288 }
 289 EXPORT_SYMBOL_GPL(snd_hdac_codec_link_down);