Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 25 Feb 2020 10:58:37 +0100
From:   Maxime Ripard <maxime@cerno.tech>
To:     Stefan Mavrodiev <stefan@olimex.com>
Cc:     wens@kernel.org, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        open list <linux-kernel@vger.kernel.org>,
        "open list:DRM DRIVERS FOR ALLWINNER A10" 
        <dri-devel@lists.freedesktop.org>,
        "moderated list:ARM/Allwinner sunXi SoC support" 
        <linux-arm-kernel@lists.infradead.org>,
        linux-sunxi <linux-sunxi@googlegroups.com>,
        Takashi Iwai <tiwai@suse.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Linux-ALSA <alsa-devel@alsa-project.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>, Chen-Yu Tsai <wens@csie.org>
Subject: Re: [linux-sunxi] [PATCH v3 1/1] drm: sun4i: hdmi: Add support for
 sun4i HDMI encoder audio
Message-ID: <20200225095837.py6v2tkpyb7bonoz@gilmour.lan>
References: <20200128140642.8404-1-stefan@olimex.com>
 <20200128140642.8404-2-stefan@olimex.com>
 <CAGb2v66kEACD0oOqoL2sx8JJJAnZzZc+EwEK8+74bZx48L-Z5A@mail.gmail.com>
 <81b0a464-22f7-4d36-e9bc-f08a52accdbc@olimex.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
        protocol="application/pgp-signature"; boundary="j63zqoiiqzwxe7qb"
Content-Disposition: inline
In-Reply-To: <81b0a464-22f7-4d36-e9bc-f08a52accdbc@olimex.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


--j63zqoiiqzwxe7qb
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

On Tue, Feb 25, 2020 at 11:45:28AM +0200, Stefan Mavrodiev wrote:
>
> On 1/29/20 6:34 PM, Chen-Yu Tsai wrote:
> > On Tue, Jan 28, 2020 at 10:07 PM Stefan Mavrodiev <stefan@olimex.com> wrote:
> > > Add HDMI audio support for the sun4i-hdmi encoder, used on
> > > the older Allwinner chips - A10, A20, A31.
> > >
> > > Most of the code is based on the BSP implementation. In it
> > > dditional formats are supported (S20_3LE and S24_LE), however
> > > there where some problems with them and only S16_LE is left.
> > >
> > > Signed-off-by: Stefan Mavrodiev <stefan@olimex.com>
> > > ---
> > > Changes for v3:
> > >   - Instead of platfrom_driver dynammicly register/unregister card
> > >   - Add Kconfig dependencies
> > >   - Restrore drvdata after card unregistering
> > >
> > > Changes for v2:
> > >   - Create a new platform driver instead of using the HDMI encoder
> > >   - Expose a new kcontrol to the userspace holding the ELD data
> > >   - Wrap all macro arguments in parentheses
> > >
> > >   drivers/gpu/drm/sun4i/Kconfig            |  11 +
> > >   drivers/gpu/drm/sun4i/Makefile           |   3 +
> > >   drivers/gpu/drm/sun4i/sun4i_hdmi.h       |  37 ++
> > >   drivers/gpu/drm/sun4i/sun4i_hdmi_audio.c | 450 +++++++++++++++++++++++
> > >   drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c   |  14 +
> > >   5 files changed, 515 insertions(+)
> > >   create mode 100644 drivers/gpu/drm/sun4i/sun4i_hdmi_audio.c
> > Since this is actually an audio driver, please include all the ALSA / ASoC
> > maintainers and mailing lists (CC-ed).
> >
> > > diff --git a/drivers/gpu/drm/sun4i/Kconfig b/drivers/gpu/drm/sun4i/Kconfig
> > > index 37e90e42943f..ca2ab5d53dd4 100644
> > > --- a/drivers/gpu/drm/sun4i/Kconfig
> > > +++ b/drivers/gpu/drm/sun4i/Kconfig
> > > @@ -23,6 +23,17 @@ config DRM_SUN4I_HDMI
> > >            Choose this option if you have an Allwinner SoC with an HDMI
> > >            controller.
> > >
> > > +config DRM_SUN4I_HDMI_AUDIO
> > > +       bool "Allwinner A10 HDMI Audio Support"
> > > +       default y
> > > +       depends on DRM_SUN4I_HDMI
> > > +       depends on SND_SOC=y || SND_SOC=DRM_SUN4I_HDMI
> > > +       select SND_PCM_ELD
> > > +       select SND_SOC_GENERIC_DMAENGINE_PCM
> > > +       help
> > > +         Choose this option if you have an Allwinner SoC with an HDMI
> > > +         controller and want to use audio.
> > > +
> > >   config DRM_SUN4I_HDMI_CEC
> > >          bool "Allwinner A10 HDMI CEC Support"
> > >          depends on DRM_SUN4I_HDMI
> > > diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile
> > > index 0d04f2447b01..492bfd28ad2e 100644
> > > --- a/drivers/gpu/drm/sun4i/Makefile
> > > +++ b/drivers/gpu/drm/sun4i/Makefile
> > > @@ -5,6 +5,9 @@ sun4i-frontend-y                += sun4i_frontend.o
> > >   sun4i-drm-y                    += sun4i_drv.o
> > >   sun4i-drm-y                    += sun4i_framebuffer.o
> > >
> > > +ifdef CONFIG_DRM_SUN4I_HDMI_AUDIO
> > > +sun4i-drm-hdmi-y               += sun4i_hdmi_audio.o
> > > +endif
> > >   sun4i-drm-hdmi-y               += sun4i_hdmi_ddc_clk.o
> > >   sun4i-drm-hdmi-y               += sun4i_hdmi_enc.o
> > >   sun4i-drm-hdmi-y               += sun4i_hdmi_i2c.o
> > > diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi.h b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
> > > index 7ad3f06c127e..28621d289655 100644
> > > --- a/drivers/gpu/drm/sun4i/sun4i_hdmi.h
> > > +++ b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
> > > @@ -42,7 +42,32 @@
> > >   #define SUN4I_HDMI_VID_TIMING_POL_VSYNC                BIT(1)
> > >   #define SUN4I_HDMI_VID_TIMING_POL_HSYNC                BIT(0)
> > >
> > > +#define SUN4I_HDMI_AUDIO_CTRL_REG      0x040
> > > +#define SUN4I_HDMI_AUDIO_CTRL_ENABLE           BIT(31)
> > > +#define SUN4I_HDMI_AUDIO_CTRL_RESET            BIT(30)
> > > +
> > > +#define SUN4I_HDMI_AUDIO_FMT_REG       0x048
> > > +#define SUN4I_HDMI_AUDIO_FMT_SRC               BIT(31)
> > > +#define SUN4I_HDMI_AUDIO_FMT_LAYOUT            BIT(3)
> > > +#define SUN4I_HDMI_AUDIO_FMT_CH_CFG(n)         ((n) - 1)
> > > +#define SUN4I_HDMI_AUDIO_FMT_CH_CFG_MASK       GENMASK(2, 0)
> > > +
> > > +#define SUN4I_HDMI_AUDIO_PCM_REG       0x4c
> > > +#define SUN4I_HDMI_AUDIO_PCM_CH_MAP(n, m)      (((m) - 1) << ((n) * 4))
> > > +#define SUN4I_HDMI_AUDIO_PCM_CH_MAP_MASK(n)    (GENMASK(2, 0) << ((n) * 4))
> > > +
> > > +#define SUN4I_HDMI_AUDIO_CTS_REG       0x050
> > > +#define SUN4I_HDMI_AUDIO_CTS(n)                        ((n) & GENMASK(19, 0))
> > > +
> > > +#define SUN4I_HDMI_AUDIO_N_REG         0x054
> > > +#define SUN4I_HDMI_AUDIO_N(n)                  ((n) & GENMASK(19, 0))
> > > +
> > > +#define SUN4I_HDMI_AUDIO_STAT0_REG     0x58
> > > +#define SUN4I_HDMI_AUDIO_STAT0_FREQ(n)         ((n) << 24)
> > > +#define SUN4I_HDMI_AUDIO_STAT0_FREQ_MASK       GENMASK(27, 24)
> > > +
> > >   #define SUN4I_HDMI_AVI_INFOFRAME_REG(n)        (0x080 + (n))
> > > +#define SUN4I_HDMI_AUDIO_INFOFRAME_REG(n)      (0x0a0 + (n))
> > >
> > >   #define SUN4I_HDMI_PAD_CTRL0_REG       0x200
> > >   #define SUN4I_HDMI_PAD_CTRL0_BIASEN            BIT(31)
> > > @@ -242,6 +267,11 @@ struct sun4i_hdmi_variant {
> > >          bool                    ddc_fifo_has_dir;
> > >   };
> > >
> > > +struct sun4i_hdmi_audio {
> > > +       struct snd_soc_card             *card;
> > > +       u8                              channels;
> > > +};
> > > +
> > >   struct sun4i_hdmi {
> > >          struct drm_connector    connector;
> > >          struct drm_encoder      encoder;
> > > @@ -283,9 +313,14 @@ struct sun4i_hdmi {
> > >          struct regmap_field     *field_ddc_sda_en;
> > >          struct regmap_field     *field_ddc_sck_en;
> > >
> > > +
> > >          struct sun4i_drv        *drv;
> > >
> > >          bool                    hdmi_monitor;
> > > +       bool                    hdmi_audio;
> > > +
> > > +       struct sun4i_hdmi_audio audio;
> > > +
> > >          struct cec_adapter      *cec_adap;
> > >
> > >          const struct sun4i_hdmi_variant *variant;
> > > @@ -294,5 +329,7 @@ struct sun4i_hdmi {
> > >   int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *clk);
> > >   int sun4i_tmds_create(struct sun4i_hdmi *hdmi);
> > >   int sun4i_hdmi_i2c_create(struct device *dev, struct sun4i_hdmi *hdmi);
> > > +int sun4i_hdmi_audio_create(struct sun4i_hdmi *hdmi);
> > > +void sun4i_hdmi_audio_destroy(struct sun4i_hdmi *hdmi);
> > >
> > >   #endif /* _SUN4I_HDMI_H_ */
> > > diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi_audio.c b/drivers/gpu/drm/sun4i/sun4i_hdmi_audio.c
> > > new file mode 100644
> > > index 000000000000..f42f2cea4e9e
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/sun4i/sun4i_hdmi_audio.c
> > > @@ -0,0 +1,450 @@
> > > +// SPDX-License-Identifier: GPL-2.0-or-later
> > > +/*
> > > + * Copyright (C) 2020 Olimex Ltd.
> > > + *   Author: Stefan Mavrodiev <stefan@olimex.com>
> > > + */
> > > +#include <linux/dma-mapping.h>
> > > +#include <linux/dmaengine.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of_dma.h>
> > > +#include <linux/regmap.h>
> > > +
> > > +#include <drm/drm_print.h>
> > > +
> > > +#include <sound/dmaengine_pcm.h>
> > > +#include <sound/pcm_drm_eld.h>
> > > +#include <sound/pcm_params.h>
> > > +#include <sound/soc.h>
> > > +
> > > +#include "sun4i_hdmi.h"
> > > +
> > > +static int sun4i_hdmi_audio_ctl_eld_info(struct snd_kcontrol *kcontrol,
> > > +                                        struct snd_ctl_elem_info *uinfo)
> > > +{
> > > +       uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
> > > +       uinfo->count = MAX_ELD_BYTES;
> > > +       return 0;
> > > +}
> > > +
> > > +static int sun4i_hdmi_audio_ctl_eld_get(struct snd_kcontrol *kcontrol,
> > > +                                       struct snd_ctl_elem_value *ucontrol)
> > > +{
> > > +       struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
> > > +       struct snd_soc_card *card = snd_soc_component_get_drvdata(component);
> > > +       struct sun4i_hdmi *hdmi = snd_soc_card_get_drvdata(card);
> > > +
> > > +       memcpy(ucontrol->value.bytes.data,
> > > +              hdmi->connector.eld,
> > > +              MAX_ELD_BYTES);
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static const struct snd_kcontrol_new sun4i_hdmi_audio_controls[] = {
> > > +       {
> > > +               .access = SNDRV_CTL_ELEM_ACCESS_READ |
> > > +                         SNDRV_CTL_ELEM_ACCESS_VOLATILE,
> > > +               .iface = SNDRV_CTL_ELEM_IFACE_PCM,
> > > +               .name = "ELD",
> > > +               .info = sun4i_hdmi_audio_ctl_eld_info,
> > > +               .get = sun4i_hdmi_audio_ctl_eld_get,
> > > +       },
> > > +};
> > > +
> > > +static const struct snd_soc_dapm_widget sun4i_hdmi_audio_widgets[] = {
> > > +       SND_SOC_DAPM_OUTPUT("TX"),
> > > +};
> > > +
> > > +static const struct snd_soc_dapm_route sun4i_hdmi_audio_routes[] = {
> > > +       { "TX", NULL, "Playback" },
> > > +};
> > > +
> > > +static const struct snd_soc_component_driver sun4i_hdmi_audio_component = {
> > > +       .controls               = sun4i_hdmi_audio_controls,
> > > +       .num_controls           = ARRAY_SIZE(sun4i_hdmi_audio_controls),
> > > +       .dapm_widgets           = sun4i_hdmi_audio_widgets,
> > > +       .num_dapm_widgets       = ARRAY_SIZE(sun4i_hdmi_audio_widgets),
> > > +       .dapm_routes            = sun4i_hdmi_audio_routes,
> > > +       .num_dapm_routes        = ARRAY_SIZE(sun4i_hdmi_audio_routes),
> > > +};
> > > +
> > > +static int sun4i_hdmi_audio_startup(struct snd_pcm_substream *substream,
> > > +                                   struct snd_soc_dai *dai)
> > > +{
> > > +       struct snd_soc_card *card = snd_soc_dai_get_drvdata(dai);
> > > +       struct sun4i_hdmi *hdmi = snd_soc_card_get_drvdata(card);
> > > +       u32 reg;
> > > +       int ret;
> > > +
> > > +       regmap_write(hdmi->regmap, SUN4I_HDMI_AUDIO_CTRL_REG, 0);
> > > +       regmap_write(hdmi->regmap,
> > > +                    SUN4I_HDMI_AUDIO_CTRL_REG,
> > > +                    SUN4I_HDMI_AUDIO_CTRL_RESET);
> > > +       ret = regmap_read_poll_timeout(hdmi->regmap,
> > > +                                      SUN4I_HDMI_AUDIO_CTRL_REG,
> > > +                                      reg, !reg, 100, 50000);
> > > +       if (ret < 0) {
> > > +               DRM_ERROR("Failed to reset HDMI Audio\n");
> > > +               return ret;
> > > +       }
> > > +
> > > +       regmap_write(hdmi->regmap,
> > > +                    SUN4I_HDMI_AUDIO_CTRL_REG,
> > > +                    SUN4I_HDMI_AUDIO_CTRL_ENABLE);
> > > +
> > > +       return snd_pcm_hw_constraint_eld(substream->runtime,
> > > +                                       hdmi->connector.eld);
> > > +}
> > > +
> > > +static void sun4i_hdmi_audio_shutdown(struct snd_pcm_substream *substream,
> > > +                                     struct snd_soc_dai *dai)
> > > +{
> > > +       struct snd_soc_card *card = snd_soc_dai_get_drvdata(dai);
> > > +       struct sun4i_hdmi *hdmi = snd_soc_card_get_drvdata(card);
> > > +
> > > +       regmap_write(hdmi->regmap, SUN4I_HDMI_AUDIO_CTRL_REG, 0);
> > > +}
> > > +
> > > +static int sun4i_hdmi_setup_audio_infoframes(struct sun4i_hdmi *hdmi)
> > > +{
> > > +       union hdmi_infoframe frame;
> > > +       u8 buffer[14];
> > > +       int i, ret;
> > > +
> > > +       ret = hdmi_audio_infoframe_init(&frame.audio);
> > > +       if (ret < 0) {
> > > +               DRM_ERROR("Failed to init HDMI audio infoframe\n");
> > > +               return ret;
> > > +       }
> > > +
> > > +       frame.audio.coding_type = HDMI_AUDIO_CODING_TYPE_STREAM;
> > > +       frame.audio.sample_frequency = HDMI_AUDIO_SAMPLE_FREQUENCY_STREAM;
> > > +       frame.audio.sample_size = HDMI_AUDIO_SAMPLE_SIZE_STREAM;
> > > +       frame.audio.channels = hdmi->audio.channels;
> > > +
> > > +       ret = hdmi_infoframe_pack(&frame, buffer, sizeof(buffer));
> > > +       if (ret < 0) {
> > > +               DRM_ERROR("Failed to pack HDMI audio infoframe\n");
> > > +               return ret;
> > > +       }
> > > +
> > > +       for (i = 0; i < sizeof(buffer); i++)
> > > +               writeb(buffer[i],
> > > +                      hdmi->base + SUN4I_HDMI_AUDIO_INFOFRAME_REG(i));
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static void sun4i_hdmi_audio_set_cts_n(struct sun4i_hdmi *hdmi,
> > > +                                      struct snd_pcm_hw_params *params)
> > > +{
> > > +       struct drm_encoder *encoder = &hdmi->encoder;
> > > +       struct drm_crtc *crtc = encoder->crtc;
> > > +       const struct drm_display_mode *mode = &crtc->state->adjusted_mode;
> > > +       u32 rate = params_rate(params);
> > > +       u32 n, cts;
> > > +       u64 tmp;
> > > +
> > > +       /**
> > > +        * Calculate Cycle Time Stamp (CTS) and Numerator (N):
> > > +        *
> > > +        * N = 128 * Samplerate / 1000
> > > +        * CTS = (Ftdms * N) / (128 * Samplerate)
> > > +        */
> > > +
> > > +       n = 128 * rate / 1000;
> > > +       tmp = (u64)(mode->clock * 1000) * n;
> > > +       do_div(tmp, 128 * rate);
> > > +       cts = tmp;
> > > +
> > > +       regmap_write(hdmi->regmap,
> > > +                    SUN4I_HDMI_AUDIO_CTS_REG,
> > > +                    SUN4I_HDMI_AUDIO_CTS(cts));
> > > +
> > > +       regmap_write(hdmi->regmap,
> > > +                    SUN4I_HDMI_AUDIO_N_REG,
> > > +                    SUN4I_HDMI_AUDIO_N(n));
> > > +}
> > > +
> > > +static int sun4i_hdmi_audio_set_hw_rate(struct sun4i_hdmi *hdmi,
> > > +                                       struct snd_pcm_hw_params *params)
> > > +{
> > > +       u32 rate = params_rate(params);
> > > +       u32 val;
> > > +
> > > +       switch (rate) {
> > > +       case 44100:
> > > +               val = 0x0;
> > > +               break;
> > > +       case 48000:
> > > +               val = 0x2;
> > > +               break;
> > > +       case 32000:
> > > +               val = 0x3;
> > > +               break;
> > > +       case 88200:
> > > +               val = 0x8;
> > > +               break;
> > > +       case 96000:
> > > +               val = 0x9;
> > > +               break;
> > > +       case 176400:
> > > +               val = 0xc;
> > > +               break;
> > > +       case 192000:
> > > +               val = 0xe;
> > > +               break;
> > > +       default:
> > > +               return -EINVAL;
> > > +       }
> > > +
> > > +       regmap_update_bits(hdmi->regmap,
> > > +                          SUN4I_HDMI_AUDIO_STAT0_REG,
> > > +                          SUN4I_HDMI_AUDIO_STAT0_FREQ_MASK,
> > > +                          SUN4I_HDMI_AUDIO_STAT0_FREQ(val));
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int sun4i_hdmi_audio_set_hw_channels(struct sun4i_hdmi *hdmi,
> > > +                                           struct snd_pcm_hw_params *params)
> > > +{
> > > +       u32 channels = params_channels(params);
> > > +
> > > +       if (channels > 8)
> > > +               return -EINVAL;
> > > +
> > > +       hdmi->audio.channels = channels;
> > > +
> > > +       regmap_update_bits(hdmi->regmap,
> > > +                          SUN4I_HDMI_AUDIO_FMT_REG,
> > > +                          SUN4I_HDMI_AUDIO_FMT_LAYOUT,
> > > +                          (channels > 2) ? SUN4I_HDMI_AUDIO_FMT_LAYOUT : 0);
> > > +
> > > +       regmap_update_bits(hdmi->regmap,
> > > +                          SUN4I_HDMI_AUDIO_FMT_REG,
> > > +                          SUN4I_HDMI_AUDIO_FMT_CH_CFG_MASK,
> > > +                          SUN4I_HDMI_AUDIO_FMT_CH_CFG(channels));
> > > +
> > > +       regmap_write(hdmi->regmap, SUN4I_HDMI_AUDIO_PCM_REG, 0x76543210);
> > > +
> > > +       /**
> > > +        * If only one channel is required, send the same sample
> > > +        * to the sink device as a left and right channel.
> > > +        */
> > > +       if (channels == 1)
> > > +               regmap_update_bits(hdmi->regmap,
> > > +                                  SUN4I_HDMI_AUDIO_PCM_REG,
> > > +                                  SUN4I_HDMI_AUDIO_PCM_CH_MAP_MASK(1),
> > > +                                  SUN4I_HDMI_AUDIO_PCM_CH_MAP(1, 1));
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int sun4i_hdmi_audio_hw_params(struct snd_pcm_substream *substream,
> > > +                                     struct snd_pcm_hw_params *params,
> > > +                                     struct snd_soc_dai *dai)
> > > +{
> > > +       struct snd_soc_card *card = snd_soc_dai_get_drvdata(dai);
> > > +       struct sun4i_hdmi *hdmi = snd_soc_card_get_drvdata(card);
> > > +       int ret;
> > > +
> > > +       ret = sun4i_hdmi_audio_set_hw_rate(hdmi, params);
> > > +       if (ret < 0)
> > > +               return ret;
> > > +
> > > +       ret = sun4i_hdmi_audio_set_hw_channels(hdmi, params);
> > > +       if (ret < 0)
> > > +               return ret;
> > > +
> > > +       sun4i_hdmi_audio_set_cts_n(hdmi, params);
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int sun4i_hdmi_audio_trigger(struct snd_pcm_substream *substream,
> > > +                                   int cmd,
> > > +                                   struct snd_soc_dai *dai)
> > > +{
> > > +       struct snd_soc_card *card = snd_soc_dai_get_drvdata(dai);
> > > +       struct sun4i_hdmi *hdmi = snd_soc_card_get_drvdata(card);
> > > +       int ret = 0;
> > > +
> > > +       switch (cmd) {
> > > +       case SNDRV_PCM_TRIGGER_START:
> > > +               ret = sun4i_hdmi_setup_audio_infoframes(hdmi);
> > > +               break;
> > > +       default:
> > > +               break;
> > > +       }
> > > +
> > > +       return ret;
> > > +}
> > > +
> > > +static const struct snd_soc_dai_ops sun4i_hdmi_audio_dai_ops = {
> > > +       .startup = sun4i_hdmi_audio_startup,
> > > +       .shutdown = sun4i_hdmi_audio_shutdown,
> > > +       .hw_params = sun4i_hdmi_audio_hw_params,
> > > +       .trigger = sun4i_hdmi_audio_trigger,
> > > +};
> > > +
> > > +static int sun4i_hdmi_audio_dai_probe(struct snd_soc_dai *dai)
> > > +{
> > > +       struct snd_dmaengine_dai_dma_data *dma_data;
> > > +
> > > +       dma_data = devm_kzalloc(dai->dev, sizeof(*dma_data), GFP_KERNEL);
> > > +       if (!dma_data)
> > > +               return -ENOMEM;
> > > +
> > > +       dma_data->addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> > > +       dma_data->maxburst = 8;
> > > +
> > > +       snd_soc_dai_init_dma_data(dai, dma_data, NULL);
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static struct snd_soc_dai_driver sun4i_hdmi_audio_dai = {
> > > +       .name = "HDMI",
> > > +       .ops = &sun4i_hdmi_audio_dai_ops,
> > > +       .probe = sun4i_hdmi_audio_dai_probe,
> > > +       .playback = {
> > > +               .stream_name    = "Playback",
> > > +               .channels_min   = 1,
> > > +               .channels_max   = 8,
> > > +               .formats        = SNDRV_PCM_FMTBIT_S16_LE,
> > > +               .rates          = SNDRV_PCM_RATE_8000_192000,
> > > +       },
> > > +};
> > > +
> > > +static const struct snd_pcm_hardware sun4i_hdmi_audio_pcm_hardware = {
> > > +       .info                   = SNDRV_PCM_INFO_INTERLEAVED |
> > > +                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
> > > +                                 SNDRV_PCM_INFO_MMAP |
> > > +                                 SNDRV_PCM_INFO_MMAP_VALID |
> > > +                                 SNDRV_PCM_INFO_PAUSE |
> > > +                                 SNDRV_PCM_INFO_RESUME,
> > > +       .formats                = SNDRV_PCM_FMTBIT_S16_LE,
> > > +       .rates                  = SNDRV_PCM_RATE_8000_192000,
> > > +       .rate_min               = 8000,
> > > +       .rate_max               = 192000,
> > > +       .channels_min           = 1,
> > > +       .channels_max           = 8,
> > > +       .buffer_bytes_max       = 128 * 1024,
> > > +       .period_bytes_min       = 4 * 1024,
> > > +       .period_bytes_max       = 32 * 1024,
> > > +       .periods_min            = 2,
> > > +       .periods_max            = 8,
> > > +       .fifo_size              = 128,
> > > +};
> > > +
> > > +static const struct snd_dmaengine_pcm_config sun4i_hdmi_audio_pcm_config = {
> > > +       .chan_names[SNDRV_PCM_STREAM_PLAYBACK] = "audio-tx",
> > > +       .pcm_hardware = &sun4i_hdmi_audio_pcm_hardware,
> > > +       .prealloc_buffer_size = 128 * 1024,
> > > +       .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
> > > +};
> > > +
> > > +struct snd_soc_card sun4i_hdmi_audio_card = {
> > > +       .name = "sun4i-hdmi",
> > > +};
> > > +
> > > +int sun4i_hdmi_audio_create(struct sun4i_hdmi *hdmi)
> > > +{
> > > +       struct snd_soc_card *card = &sun4i_hdmi_audio_card;
> > > +       struct snd_soc_dai_link_component *comp;
> > > +       struct snd_soc_dai_link *link;
> > > +       int ret;
> > > +
> > > +       ret = snd_dmaengine_pcm_register(hdmi->dev,
> > > +                                        &sun4i_hdmi_audio_pcm_config, 0);
> > > +       if (ret < 0) {
> > > +               DRM_ERROR("Could not register PCM\n");
> > > +               return ret;
> > > +       }
> > > +
> > > +       ret = snd_soc_register_component(hdmi->dev,
> > > +                                        &sun4i_hdmi_audio_component,
> > > +                                        &sun4i_hdmi_audio_dai, 1);
> > > +       if (ret < 0) {
> > > +               DRM_ERROR("Could not register DAI\n");
> > > +               goto unregister_pcm;
> > > +       }
> > > +
> > > +       link = devm_kzalloc(hdmi->dev, sizeof(*link), GFP_KERNEL);
> > > +       if (!link) {
> > > +               ret = -ENOMEM;
> > > +               goto unregister_component;
> > > +       }
> > > +
> > > +       comp = devm_kzalloc(hdmi->dev, sizeof(*comp) * 3, GFP_KERNEL);
> > > +       if (!comp) {
> > > +               ret = -ENOMEM;
> > > +               goto unregister_component;
> > > +       }
> > > +
> > > +       link->cpus = &comp[0];
> > > +       link->codecs = &comp[1];
> > > +       link->platforms = &comp[2];
> > > +
> > > +       link->num_cpus = 1;
> > > +       link->num_codecs = 1;
> > > +       link->num_platforms = 1;
> > > +
> > > +       link->playback_only = 1;
> > > +
> > > +       link->name = "SUN4I-HDMI";
> > > +       link->stream_name = "SUN4I-HDMI PCM";
> > > +
> > > +       link->codecs->name = dev_name(hdmi->dev);
> > > +       link->codecs->dai_name  = sun4i_hdmi_audio_dai.name;
> > > +
> > > +       link->cpus->dai_name = dev_name(hdmi->dev);
> > > +
> > > +       link->platforms->name = dev_name(hdmi->dev);
> > > +
> > > +       link->dai_fmt = SND_SOC_DAIFMT_I2S;
> > > +
> > > +       card->dai_link = link;
> > > +       card->num_links = 1;
> > > +       card->dev = hdmi->dev;
> > > +
> > > +       hdmi->audio.card = card;
> > > +
> > > +       /**
> > > +        * snd_soc_register_card() will overwrite the driver_data pointer.
> > > +        * So before registering the card, store the original pointer in
> > > +        * card->drvdata.
> > > +        */
> > > +       snd_soc_card_set_drvdata(card, hdmi);
> > > +       ret = snd_soc_register_card(card);
> > > +       if (ret)
> > > +               goto unregister_component;
> > So using ASoC with all the components IMHO is just adding dead weight. The
> > audio interface for this particular hardware is just a FIFO that needs to
> > be written to by an external DMA engine, and a bunch of controls to setup
> > the parameters of the HDMI audio stream. There's no power sequencing to do,
> > and no actual individual components to control. There's no reason you couldn't
> > use just the ALSA DMAENGINE helpers to create a simple ALSA sound card.
> >
> > (Maybe we could clean it up after it's merged? Would there be any issues
> >   with backward compatibility?)
> >
> > I think the only example of this besides ASoC is the PXA2xx sound library
> > and AC97 driver:
> >
> >    - sound/arm/pxa2xx-pcm-lib.c
> >    - sound/arm/pxa2xx-ac97.c
>
> I'd like to hear Maxime opinion on this. I get it why it's overkill to use
> ASoC.
> However it will take only couple of lines to make the changes for v4. On the
> other
> side with dropping the ASoC, the driver must be almost rewritten. It's not
> such a big deal,
> but I want to know that this is the right thing to do.

I don't really have an opinion on this, either way is fine for me, so
if it's simpler to go for ALSA, then let's do it :)

Maxime

--j63zqoiiqzwxe7qb
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXlTvzQAKCRDj7w1vZxhR
xcfcAP4vXsSMFgNjurcgJoQ+w1ZJzQ8Sm02R6pJ5GDrpqSv46wD8Dne6WOUxO7v1
BFaJ38xRqthGU9r0pGDB5btH1BiyjQs=
=H9tj
-----END PGP SIGNATURE-----

--j63zqoiiqzwxe7qb--