Re: [PATCH v5 10/32] ASoC: qcom: Add USB backend ASoC driver for Q6

From: Wesley Cheng
Date: Thu Aug 31 2023 - 15:35:30 EST


Hi,

On 8/30/2023 5:50 AM, Amadeusz Sławiński wrote:
On 8/29/2023 11:06 PM, Wesley Cheng wrote:
Create a USB BE component that will register a new USB port to the ASoC USB
framework.  This will handle determination on if the requested audio
profile is supported by the USB device currently selected.

Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
---
  include/sound/q6usboffload.h  |  20 ++++
  sound/soc/qcom/Kconfig        |   4 +
  sound/soc/qcom/qdsp6/Makefile |   1 +
  sound/soc/qcom/qdsp6/q6usb.c  | 200 ++++++++++++++++++++++++++++++++++
  4 files changed, 225 insertions(+)
  create mode 100644 include/sound/q6usboffload.h
  create mode 100644 sound/soc/qcom/qdsp6/q6usb.c

diff --git a/include/sound/q6usboffload.h b/include/sound/q6usboffload.h
new file mode 100644
index 000000000000..4fb1912d9f55
--- /dev/null
+++ b/include/sound/q6usboffload.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * linux/sound/q6usboffload.h -- QDSP6 USB offload
+ *
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+/**
+ * struct q6usb_offload
+ * @dev - dev handle to usb be
+ * @sid - streamID for iommu
+ * @intr_num - usb interrupter number
+ * @domain - allocated iommu domain
+ **/
+struct q6usb_offload {
+    struct device *dev;
+    long long sid;
+    u32 intr_num;
+    struct iommu_domain *domain;
+};
diff --git a/sound/soc/qcom/Kconfig b/sound/soc/qcom/Kconfig
index e7b00d1d9e99..bb285af6bb04 100644
--- a/sound/soc/qcom/Kconfig
+++ b/sound/soc/qcom/Kconfig
@@ -114,6 +114,9 @@ config SND_SOC_QDSP6_APM
  config SND_SOC_QDSP6_PRM_LPASS_CLOCKS
      tristate
+config SND_SOC_QDSP6_USB
+    tristate
+
  config SND_SOC_QDSP6_PRM
      tristate
      select SND_SOC_QDSP6_PRM_LPASS_CLOCKS
@@ -134,6 +137,7 @@ config SND_SOC_QDSP6
      select SND_SOC_TOPOLOGY
      select SND_SOC_QDSP6_APM
      select SND_SOC_QDSP6_PRM
+    select SND_SOC_QDSP6_USB
      help
       To add support for MSM QDSP6 Soc Audio.
       This will enable sound soc platform specific
diff --git a/sound/soc/qcom/qdsp6/Makefile b/sound/soc/qcom/qdsp6/Makefile
index 3963bf234664..c9457ee898d0 100644
--- a/sound/soc/qcom/qdsp6/Makefile
+++ b/sound/soc/qcom/qdsp6/Makefile
@@ -17,3 +17,4 @@ obj-$(CONFIG_SND_SOC_QDSP6_APM_DAI) += q6apm-dai.o
  obj-$(CONFIG_SND_SOC_QDSP6_APM_LPASS_DAI) += q6apm-lpass-dais.o
  obj-$(CONFIG_SND_SOC_QDSP6_PRM) += q6prm.o
  obj-$(CONFIG_SND_SOC_QDSP6_PRM_LPASS_CLOCKS) += q6prm-clocks.o
+obj-$(CONFIG_SND_SOC_QDSP6_USB) += q6usb.o
diff --git a/sound/soc/qcom/qdsp6/q6usb.c b/sound/soc/qcom/qdsp6/q6usb.c
new file mode 100644
index 000000000000..88aa0a64201a
--- /dev/null
+++ b/sound/soc/qcom/qdsp6/q6usb.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma-map-ops.h>
+
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/soc-usb.h>
+#include <sound/pcm_params.h>
+#include <sound/asound.h>
+#include <sound/q6usboffload.h>
+
+#include "q6dsp-lpass-ports.h"
+#include "q6afe.h"
+
+#define SID_MASK    0xF
+
+struct q6usb_port_data {
+    struct q6afe_usb_cfg usb_cfg;
+    struct snd_soc_usb *usb;
+    struct q6usb_offload priv;
+    int active_idx;
+};
+
+static const struct snd_soc_dapm_widget q6usb_dai_widgets[] = {
+    SND_SOC_DAPM_HP("USB_RX_BE", NULL),
+};
+
+static const struct snd_soc_dapm_route q6usb_dapm_routes[] = {
+    {"USB Playback", NULL, "USB_RX_BE"},
+};
+
+static int q6usb_hw_params(struct snd_pcm_substream *substream,
+               struct snd_pcm_hw_params *params,
+               struct snd_soc_dai *dai)
+{
+    return 0;
+}

Missing new line after closing bracket between function and following struct.


Thanks for the review, will fix this.

+static const struct snd_soc_dai_ops q6usb_ops = {
+    .hw_params = q6usb_hw_params,
+};
+
+static struct snd_soc_dai_driver q6usb_be_dais[] = {
+    {
+        .playback = {
+            .stream_name = "USB BE RX",
+            .rates = SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |
+                SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 |
+                SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
+                SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000 |
+                SNDRV_PCM_RATE_192000,
+            .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |
+                SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |
+                SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE |
+                SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_U24_BE,
+            .channels_min = 1,
+            .channels_max = 2,
+            .rate_max =     192000,
+            .rate_min =    8000,
+        },
+        .id = USB_RX,
+        .name = "USB_RX_BE",
+        .ops = &q6usb_ops,
+    },
+};
+
+static int q6usb_audio_ports_of_xlate_dai_name(struct snd_soc_component *component,
+                    const struct of_phandle_args *args,
+                    const char **dai_name)
+{
+    int id = args->args[0];
+    int ret = -EINVAL;
+    int i;
+
+    for (i = 0; i  < ARRAY_SIZE(q6usb_be_dais); i++) {

Double space after second i.


Will change.

+        if (q6usb_be_dais[i].id == id) {
+            *dai_name = q6usb_be_dais[i].name;
+            ret = 0;
+            break;
+        }
+    }
+
+    return ret;
+}
+
+static int q6usb_alsa_connection_cb(struct snd_soc_usb *usb,
+            struct snd_soc_usb_device *sdev, bool connected)
+{
+    struct q6usb_port_data *data;
+
+    if (!usb->component)
+        return -ENODEV;
+
+    data = dev_get_drvdata(usb->component->dev);
+
+    if (connected)
+        /* We only track the latest USB headset plugged in */
+        data->active_idx = sdev->card_idx;

Maybe add brackets around both comment and code? Not sure what guidance there is in such cases, but above code looks weird to me.


Sure.

+
+    return 0;
+}
+
+static int q6usb_component_probe(struct snd_soc_component *component)
+{
+    struct q6usb_port_data *data = dev_get_drvdata(component->dev);
+
+    data->usb = snd_soc_usb_add_port(component->dev, &data->priv, q6usb_alsa_connection_cb);
+    if (IS_ERR(data->usb)) {
+        dev_err(component->dev, "failed to add usb port\n");
+        return -ENODEV;
+    }
+
+    data->usb->component = component;
+
+    return 0;
+}
+
+static void q6usb_component_remove(struct snd_soc_component *component)
+{
+    snd_soc_usb_remove_port(component->dev);
+}
+
+static const struct snd_soc_component_driver q6usb_dai_component = {
+    .probe = q6usb_component_probe,
+    .remove = q6usb_component_remove,
+    .name = "q6usb-dai-component",
+    .dapm_widgets = q6usb_dai_widgets,
+    .num_dapm_widgets = ARRAY_SIZE(q6usb_dai_widgets),
+    .dapm_routes = q6usb_dapm_routes,
+    .num_dapm_routes = ARRAY_SIZE(q6usb_dapm_routes),
+    .of_xlate_dai_name = q6usb_audio_ports_of_xlate_dai_name,
+};
+
+static int q6usb_dai_dev_probe(struct platform_device *pdev)
+{
+    struct device_node *node = pdev->dev.of_node;
+    struct q6usb_port_data *data;
+    struct device *dev = &pdev->dev;
+    struct of_phandle_args args;
+    int ret;
+
+    data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+    if (!data)
+        return -ENOMEM;
+
+    ret = of_property_read_u32(node, "qcom,usb-audio-intr-num",
+                &data->priv.intr_num);
+    if (ret) {
+        dev_err(&pdev->dev, "failed to read intr num.\n");
+        return ret;
+    }
+
+    ret = of_parse_phandle_with_fixed_args(node, "iommus", 1, 0, &args);
+    if (ret < 0)
+        data->priv.sid = -1;
+    else
+        data->priv.sid = args.args[0] & SID_MASK;
+
+    data->priv.domain = iommu_get_domain_for_dev(&pdev->dev);
+
+    data->priv.dev = dev;
+    dev_set_drvdata(dev, data);
+
+    return devm_snd_soc_register_component(dev, &q6usb_dai_component,
+                    q6usb_be_dais, ARRAY_SIZE(q6usb_be_dais));
+}
+
+static int q6usb_dai_dev_remove(struct platform_device *pdev)
+{
+    return 0;
+}

Does platform driver really need empty remove function? Remove it.


Wasn't too sure about this either, so I included it to be consistent. Will remove this and add a small comment on why it isn't required..

Thanks
Wesley Cheng