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