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