The new SPDIF TX controller is a serial port compliant with the IEC-
60958 standard. It also supports programmable User Data and Channel
Status fields.

This IP is embedded in Microchip's sama7g5 SoC.

Signed-off-by: Codrin Ciubotariu <codrin.ciubota...@microchip.com>
---

Changes in v2:
 - none

 sound/soc/atmel/Kconfig        |  12 +
 sound/soc/atmel/Makefile       |   2 +
 sound/soc/atmel/mchp-spdiftx.c | 864 +++++++++++++++++++++++++++++++++
 3 files changed, 878 insertions(+)
 create mode 100644 sound/soc/atmel/mchp-spdiftx.c

diff --git a/sound/soc/atmel/Kconfig b/sound/soc/atmel/Kconfig
index 71f2d42188c4..93beb7d670a3 100644
--- a/sound/soc/atmel/Kconfig
+++ b/sound/soc/atmel/Kconfig
@@ -132,4 +132,16 @@ config SND_MCHP_SOC_I2S_MCC
          and supports a Time Division Multiplexed (TDM) interface with
          external multi-channel audio codecs.
 
+config SND_MCHP_SOC_SPDIFTX
+       tristate "Microchip ASoC driver for boards using S/PDIF TX"
+       depends on OF && (ARCH_AT91 || COMPILE_TEST)
+       select SND_SOC_GENERIC_DMAENGINE_PCM
+       select REGMAP_MMIO
+       help
+         Say Y or M if you want to add support for Microchip S/PDIF TX ASoc
+         driver on the following Microchip platforms:
+         - sama7g5
+
+         This S/PDIF TX driver is compliant with IEC-60958 standard and
+         includes programable User Data and Channel Status fields.
 endif
diff --git a/sound/soc/atmel/Makefile b/sound/soc/atmel/Makefile
index c7d2989791be..3fd89a0063df 100644
--- a/sound/soc/atmel/Makefile
+++ b/sound/soc/atmel/Makefile
@@ -5,6 +5,7 @@ snd-soc-atmel-pcm-dma-objs := atmel-pcm-dma.o
 snd-soc-atmel_ssc_dai-objs := atmel_ssc_dai.o
 snd-soc-atmel-i2s-objs := atmel-i2s.o
 snd-soc-mchp-i2s-mcc-objs := mchp-i2s-mcc.o
+snd-soc-mchp-spdiftx-objs := mchp-spdiftx.o
 
 # pdc and dma need to both be built-in if any user of
 # ssc is built-in.
@@ -17,6 +18,7 @@ endif
 obj-$(CONFIG_SND_ATMEL_SOC_SSC) += snd-soc-atmel_ssc_dai.o
 obj-$(CONFIG_SND_ATMEL_SOC_I2S) += snd-soc-atmel-i2s.o
 obj-$(CONFIG_SND_MCHP_SOC_I2S_MCC) += snd-soc-mchp-i2s-mcc.o
+obj-$(CONFIG_SND_MCHP_SOC_SPDIFTX) += snd-soc-mchp-spdiftx.o
 
 # AT91 Machine Support
 snd-soc-sam9g20-wm8731-objs := sam9g20_wm8731.o
diff --git a/sound/soc/atmel/mchp-spdiftx.c b/sound/soc/atmel/mchp-spdiftx.c
new file mode 100644
index 000000000000..738f6788212e
--- /dev/null
+++ b/sound/soc/atmel/mchp-spdiftx.c
@@ -0,0 +1,864 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Driver for Microchip S/PDIF TX Controller
+//
+// Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
+//
+// Author: Codrin Ciubotariu <codrin.ciubota...@microchip.com>
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+
+#include <sound/asoundef.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+/*
+ * ---- S/PDIF Transmitter Controller Register map ----
+ */
+#define SPDIFTX_CR                     0x00    /* Control Register */
+#define SPDIFTX_MR                     0x04    /* Mode Register */
+#define SPDIFTX_CDR                    0x0C    /* Common Data Register */
+
+#define SPDIFTX_IER                    0x14    /* Interrupt Enable Register */
+#define SPDIFTX_IDR                    0x18    /* Interrupt Disable Register */
+#define SPDIFTX_IMR                    0x1C    /* Interrupt Mask Register */
+#define SPDIFTX_ISR                    0x20    /* Interrupt Status Register */
+
+#define SPDIFTX_CH1UD(reg)     (0x50 + (reg) * 4)      /* User Data 1 Register 
x */
+#define SPDIFTX_CH1S(reg)      (0x80 + (reg) * 4)      /* Channel Status 1 
Register x */
+
+#define SPDIFTX_VERSION                        0xF0
+
+/*
+ * ---- Control Register (Write-only) ----
+ */
+#define SPDIFTX_CR_SWRST               BIT(0)  /* Software Reset */
+#define SPDIFTX_CR_FCLR                        BIT(1)  /* FIFO clear */
+
+/*
+ * ---- Mode Register (Read/Write) ----
+ */
+/* Transmit Enable */
+#define SPDIFTX_MR_TXEN_MASK           GENMASK(0, 0)
+#define SPDIFTX_MR_TXEN_DISABLE                (0 << 0)
+#define SPDIFTX_MR_TXEN_ENABLE         (1 << 0)
+
+/* Multichannel Transfer */
+#define SPDIFTX_MR_MULTICH_MASK                GENAMSK(1, 1)
+#define SPDIFTX_MR_MULTICH_MONO                (0 << 1)
+#define SPDIFTX_MR_MULTICH_DUAL                (1 << 1)
+
+/* Data Word Endian Mode */
+#define SPDIFTX_MR_ENDIAN_MASK         GENMASK(2, 2)
+#define SPDIFTX_MR_ENDIAN_LITTLE       (0 << 2)
+#define SPDIFTX_MR_ENDIAN_BIG          (1 << 2)
+
+/* Data Justification */
+#define SPDIFTX_MR_JUSTIFY_MASK                GENMASK(3, 3)
+#define SPDIFTX_MR_JUSTIFY_LSB         (0 << 3)
+#define SPDIFTX_MR_JUSTIFY_MSB         (1 << 3)
+
+/* Common Audio Register Transfer Mode */
+#define SPDIFTX_MR_CMODE_MASK                  GENMASK(5, 4)
+#define SPDIFTX_MR_CMODE_INDEX_ACCESS          (0 << 4)
+#define SPDIFTX_MR_CMODE_TOGGLE_ACCESS         (1 << 4)
+#define SPDIFTX_MR_CMODE_INTERLVD_ACCESS       (2 << 4)
+
+/* Valid Bits per Sample */
+#define SPDIFTX_MR_VBPS_MASK           GENMASK(13, 8)
+#define SPDIFTX_MR_VBPS(bps)           (((bps) << 8) & SPDIFTX_MR_VBPS_MASK)
+
+/* Chunk Size */
+#define SPDIFTX_MR_CHUNK_MASK          GENMASK(19, 16)
+#define SPDIFTX_MR_CHUNK(size)         (((size) << 16) & SPDIFTX_MR_CHUNK_MASK)
+
+/* Validity Bits for Channels 1 and 2 */
+#define SPDIFTX_MR_VALID1                      BIT(24)
+#define SPDIFTX_MR_VALID2                      BIT(25)
+
+/* Disable Null Frame on underrrun */
+#define SPDIFTX_MR_DNFR_MASK           GENMASK(27, 27)
+#define SPDIFTX_MR_DNFR_INVALID                (0 << 27)
+#define SPDIFTX_MR_DNFR_VALID          (1 << 27)
+
+/* Bytes per Sample */
+#define SPDIFTX_MR_BPS_MASK            GENMASK(29, 28)
+#define SPDIFTX_MR_BPS(bytes) \
+       ((((bytes) - 1) << 28) & SPDIFTX_MR_BPS_MASK)
+
+/*
+ * ---- Interrupt Enable/Disable/Mask/Status Register (Write/Read-only) ----
+ */
+#define SPDIFTX_IR_TXRDY               BIT(0)
+#define SPDIFTX_IR_TXEMPTY             BIT(1)
+#define SPDIFTX_IR_TXFULL              BIT(2)
+#define SPDIFTX_IR_TXCHUNK             BIT(3)
+#define SPDIFTX_IR_TXUDR               BIT(4)
+#define SPDIFTX_IR_TXOVR               BIT(5)
+#define SPDIFTX_IR_CSRDY               BIT(6)
+#define SPDIFTX_IR_UDRDY               BIT(7)
+#define SPDIFTX_IR_TXRDYCH(ch)         BIT((ch) + 8)
+#define SPDIFTX_IR_SECE                        BIT(10)
+#define SPDIFTX_IR_TXUDRCH(ch)         BIT((ch) + 11)
+#define SPDIFTX_IR_BEND                        BIT(13)
+
+static bool mchp_spdiftx_readable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case SPDIFTX_MR:
+       case SPDIFTX_IMR:
+       case SPDIFTX_ISR:
+       case SPDIFTX_CH1UD(0):
+       case SPDIFTX_CH1UD(1):
+       case SPDIFTX_CH1UD(2):
+       case SPDIFTX_CH1UD(3):
+       case SPDIFTX_CH1UD(4):
+       case SPDIFTX_CH1UD(5):
+       case SPDIFTX_CH1S(0):
+       case SPDIFTX_CH1S(1):
+       case SPDIFTX_CH1S(2):
+       case SPDIFTX_CH1S(3):
+       case SPDIFTX_CH1S(4):
+       case SPDIFTX_CH1S(5):
+               return true;
+       default:
+               return false;
+       }
+}
+
+static bool mchp_spdiftx_writeable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case SPDIFTX_CR:
+       case SPDIFTX_MR:
+       case SPDIFTX_CDR:
+       case SPDIFTX_IER:
+       case SPDIFTX_IDR:
+       case SPDIFTX_CH1UD(0):
+       case SPDIFTX_CH1UD(1):
+       case SPDIFTX_CH1UD(2):
+       case SPDIFTX_CH1UD(3):
+       case SPDIFTX_CH1UD(4):
+       case SPDIFTX_CH1UD(5):
+       case SPDIFTX_CH1S(0):
+       case SPDIFTX_CH1S(1):
+       case SPDIFTX_CH1S(2):
+       case SPDIFTX_CH1S(3):
+       case SPDIFTX_CH1S(4):
+       case SPDIFTX_CH1S(5):
+               return true;
+       default:
+               return false;
+       }
+}
+
+static bool mchp_spdiftx_precious_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case SPDIFTX_CDR:
+       case SPDIFTX_ISR:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static const struct regmap_config mchp_spdiftx_regmap_config = {
+       .reg_bits = 32,
+       .reg_stride = 4,
+       .val_bits = 32,
+       .max_register = SPDIFTX_VERSION,
+       .readable_reg = mchp_spdiftx_readable_reg,
+       .writeable_reg = mchp_spdiftx_writeable_reg,
+       .precious_reg = mchp_spdiftx_precious_reg,
+};
+
+#define SPDIFTX_GCLK_RATIO     128
+
+#define SPDIFTX_CS_BITS                192
+#define SPDIFTX_UD_BITS                192
+
+struct mchp_spdiftx_mixer_control {
+       unsigned char                           ch_stat[SPDIFTX_CS_BITS / 8];
+       unsigned char                           user_data[SPDIFTX_UD_BITS / 8];
+       spinlock_t                              lock;
+};
+
+struct mchp_spdiftx_dev {
+       struct mchp_spdiftx_mixer_control       control;
+       struct snd_dmaengine_dai_dma_data       playback;
+       struct device                           *dev;
+       struct regmap                           *regmap;
+       struct clk                              *pclk;
+       struct clk                              *gclk;
+       unsigned int                            fmt;
+       const struct mchp_i2s_caps              *caps;
+       int                                     gclk_enabled:1;
+};
+
+static inline int mchp_spdiftx_is_running(struct mchp_spdiftx_dev *dev)
+{
+       u32 mr;
+
+       regmap_read(dev->regmap, SPDIFTX_MR, &mr);
+       return !!(mr & SPDIFTX_MR_TXEN_ENABLE);
+}
+
+static void mchp_spdiftx_channel_status_write(struct mchp_spdiftx_dev *dev)
+{
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       u32 val;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(ctrl->ch_stat) / 4; i++) {
+               val = (ctrl->ch_stat[(i * 4) + 0] << 0) |
+                     (ctrl->ch_stat[(i * 4) + 1] << 8) |
+                     (ctrl->ch_stat[(i * 4) + 2] << 16) |
+                     (ctrl->ch_stat[(i * 4) + 3] << 24);
+
+               regmap_write(dev->regmap, SPDIFTX_CH1S(i), val);
+       }
+}
+
+static void mchp_spdiftx_user_data_write(struct mchp_spdiftx_dev *dev)
+{
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       u32 val;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(ctrl->user_data) / 4; i++) {
+               val = (ctrl->user_data[(i * 4) + 0] << 0) |
+                     (ctrl->user_data[(i * 4) + 1] << 8) |
+                     (ctrl->user_data[(i * 4) + 2] << 16) |
+                     (ctrl->user_data[(i * 4) + 3] << 24);
+
+               regmap_write(dev->regmap, SPDIFTX_CH1UD(i), val);
+       }
+}
+
+static irqreturn_t mchp_spdiftx_interrupt(int irq, void *dev_id)
+{
+       struct mchp_spdiftx_dev *dev = dev_id;
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       u32 sr, imr, pending, idr = 0;
+
+       regmap_read(dev->regmap, SPDIFTX_ISR, &sr);
+       regmap_read(dev->regmap, SPDIFTX_IMR, &imr);
+       pending = sr & imr;
+
+       if (!pending)
+               return IRQ_NONE;
+
+       if (pending & SPDIFTX_IR_TXUDR) {
+               dev_warn(dev->dev, "underflow detected\n");
+               idr |= SPDIFTX_IR_TXUDR;
+       }
+
+       if (pending & SPDIFTX_IR_TXOVR) {
+               dev_warn(dev->dev, "overflow detected\n");
+               idr |= SPDIFTX_IR_TXOVR;
+       }
+
+       if (pending & SPDIFTX_IR_UDRDY) {
+               spin_lock(&ctrl->lock);
+               mchp_spdiftx_user_data_write(dev);
+               spin_unlock(&ctrl->lock);
+               idr |= SPDIFTX_IR_UDRDY;
+       }
+
+       if (pending & SPDIFTX_IR_CSRDY) {
+               spin_lock(&ctrl->lock);
+               mchp_spdiftx_channel_status_write(dev);
+               spin_unlock(&ctrl->lock);
+               idr |= SPDIFTX_IR_CSRDY;
+       }
+
+       regmap_write(dev->regmap, SPDIFTX_IDR, idr);
+
+       return IRQ_HANDLED;
+}
+
+static int mchp_spdiftx_dai_startup(struct snd_pcm_substream *substream,
+                                   struct snd_soc_dai *dai)
+{
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       int err;
+
+       err = clk_prepare_enable(dev->pclk);
+       if (err) {
+               dev_err(dev->dev,
+                       "failed to enable the peripheral clock: %d\n", err);
+               return err;
+       }
+
+       /* Software reset the IP */
+       regmap_write(dev->regmap, SPDIFTX_CR,
+                    SPDIFTX_CR_SWRST | SPDIFTX_CR_FCLR);
+
+       return 0;
+}
+
+static void mchp_spdiftx_dai_shutdown(struct snd_pcm_substream *substream,
+                                     struct snd_soc_dai *dai)
+{
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+
+       /* Disable interrupts */
+       regmap_write(dev->regmap, SPDIFTX_IDR, 0xffffffff);
+
+       clk_disable_unprepare(dev->pclk);
+}
+
+static int mchp_spdiftx_trigger(struct snd_pcm_substream *substream, int cmd,
+                               struct snd_soc_dai *dai)
+{
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       u32 mr;
+       int running;
+       int ret;
+
+       /* do not start/stop while channel status or user data is updated */
+       spin_lock(&ctrl->lock);
+       regmap_read(dev->regmap, SPDIFTX_MR, &mr);
+       running = !!(mr & SPDIFTX_MR_TXEN_ENABLE);
+
+       switch (cmd) {
+       case SNDRV_PCM_TRIGGER_START:
+       case SNDRV_PCM_TRIGGER_RESUME:
+       case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+               if (!running) {
+                       mr &= ~SPDIFTX_MR_TXEN_MASK;
+                       mr |= SPDIFTX_MR_TXEN_ENABLE;
+               }
+               break;
+       case SNDRV_PCM_TRIGGER_STOP:
+       case SNDRV_PCM_TRIGGER_SUSPEND:
+       case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+               if (running) {
+                       mr &= ~SPDIFTX_MR_TXEN_MASK;
+                       mr |= SPDIFTX_MR_TXEN_DISABLE;
+               }
+               break;
+       default:
+               spin_unlock(&ctrl->lock);
+               return -EINVAL;
+       }
+
+       ret = regmap_write(dev->regmap, SPDIFTX_MR, mr);
+       spin_unlock(&ctrl->lock);
+       if (ret) {
+               dev_err(dev->dev, "unable to disable TX: %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int mchp_spdiftx_hw_params(struct snd_pcm_substream *substream,
+                                 struct snd_pcm_hw_params *params,
+                                 struct snd_soc_dai *dai)
+{
+       unsigned long flags;
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       u32 mr;
+       unsigned int bps = params_physical_width(params) / 8;
+       int ret;
+
+       dev_dbg(dev->dev, "%s() rate=%u format=%#x width=%u channels=%u\n",
+               __func__, params_rate(params), params_format(params),
+               params_width(params), params_channels(params));
+
+       if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+               dev_err(dev->dev, "Capture is not supported\n");
+               return -EINVAL;
+       }
+
+       regmap_read(dev->regmap, SPDIFTX_MR, &mr);
+
+       if (mr & SPDIFTX_MR_TXEN_ENABLE) {
+               dev_err(dev->dev, "PCM already running\n");
+               return -EBUSY;
+       }
+
+       /* Defaults: Toggle mode, justify to LSB, chunksize 1 */
+       mr = SPDIFTX_MR_CMODE_TOGGLE_ACCESS | SPDIFTX_MR_JUSTIFY_LSB;
+       dev->playback.maxburst = 1;
+       switch (params_channels(params)) {
+       case 1:
+               mr |= SPDIFTX_MR_MULTICH_MONO;
+               break;
+       case 2:
+               mr |= SPDIFTX_MR_MULTICH_DUAL;
+               if (bps > 2)
+                       dev->playback.maxburst = 2;
+               break;
+       default:
+               dev_err(dev->dev, "unsupported number of channels: %d\n",
+                       params_channels(params));
+               return -EINVAL;
+       }
+       mr |= SPDIFTX_MR_CHUNK(dev->playback.maxburst);
+
+       switch (params_format(params)) {
+       case SNDRV_PCM_FORMAT_S8:
+               mr |= SPDIFTX_MR_VBPS(8);
+               break;
+       case SNDRV_PCM_FORMAT_S16_BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S16_LE:
+               mr |= SPDIFTX_MR_VBPS(16);
+               break;
+       case SNDRV_PCM_FORMAT_S18_3BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S18_3LE:
+               mr |= SPDIFTX_MR_VBPS(18);
+               break;
+       case SNDRV_PCM_FORMAT_S20_3BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S20_3LE:
+               mr |= SPDIFTX_MR_VBPS(20);
+               break;
+       case SNDRV_PCM_FORMAT_S24_3BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S24_3LE:
+               mr |= SPDIFTX_MR_VBPS(24);
+               break;
+       case SNDRV_PCM_FORMAT_S24_BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S24_LE:
+               mr |= SPDIFTX_MR_VBPS(24);
+               break;
+       case SNDRV_PCM_FORMAT_S32_BE:
+               mr |= SPDIFTX_MR_ENDIAN_BIG;
+               fallthrough;
+       case SNDRV_PCM_FORMAT_S32_LE:
+               mr |= SPDIFTX_MR_VBPS(32);
+               break;
+       default:
+               dev_err(dev->dev, "unsupported PCM format: %d\n",
+                       params_format(params));
+               return -EINVAL;
+       }
+
+       mr |= SPDIFTX_MR_BPS(bps);
+
+       spin_lock_irqsave(&ctrl->lock, flags);
+       ctrl->ch_stat[3] &= ~IEC958_AES3_CON_FS;
+       switch (params_rate(params)) {
+       case 22050:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_22050;
+               break;
+       case 24000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_24000;
+               break;
+       case 32000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_32000;
+               break;
+       case 44100:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_44100;
+               break;
+       case 48000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_48000;
+               break;
+       case 88200:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_88200;
+               break;
+       case 96000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_96000;
+               break;
+       case 176400:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_176400;
+               break;
+       case 192000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_192000;
+               break;
+       case 8000:
+       case 11025:
+       case 16000:
+       case 64000:
+               ctrl->ch_stat[3] |= IEC958_AES3_CON_FS_NOTID;
+               break;
+       default:
+               dev_err(dev->dev, "unsupported sample frequency: %u\n",
+                       params_rate(params));
+               spin_unlock_irqrestore(&ctrl->lock, flags);
+               return -EINVAL;
+       }
+       mchp_spdiftx_channel_status_write(dev);
+       spin_unlock_irqrestore(&ctrl->lock, flags);
+       mr |= SPDIFTX_MR_VALID1 | SPDIFTX_MR_VALID2;
+
+       if (dev->gclk_enabled) {
+               clk_disable_unprepare(dev->gclk);
+               dev->gclk_enabled = 0;
+       }
+       ret = clk_set_rate(dev->gclk, params_rate(params) *
+                                     SPDIFTX_GCLK_RATIO);
+       if (ret) {
+               dev_err(dev->dev,
+                       "unable to change gclk rate to: rate %u * ratio %u\n",
+                       params_rate(params), SPDIFTX_GCLK_RATIO);
+               return ret;
+       }
+       ret = clk_prepare_enable(dev->gclk);
+       if (ret) {
+               dev_err(dev->dev, "unable to enable gclk: %d\n", ret);
+               return ret;
+       }
+       dev->gclk_enabled = 1;
+       dev_dbg(dev->dev, "%s(): GCLK set to %d\n", __func__,
+               params_rate(params) * SPDIFTX_GCLK_RATIO);
+
+       /* Enable interrupts */
+       regmap_write(dev->regmap, SPDIFTX_IER,
+                    SPDIFTX_IR_TXUDR | SPDIFTX_IR_TXOVR);
+
+       regmap_write(dev->regmap, SPDIFTX_MR, mr);
+
+       return 0;
+}
+
+static int mchp_spdiftx_hw_free(struct snd_pcm_substream *substream,
+                               struct snd_soc_dai *dai)
+{
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+
+       regmap_write(dev->regmap, SPDIFTX_IDR,
+                    SPDIFTX_IR_TXUDR | SPDIFTX_IR_TXOVR);
+       if (dev->gclk_enabled) {
+               clk_disable_unprepare(dev->gclk);
+               dev->gclk_enabled = 0;
+       }
+
+       return regmap_write(dev->regmap, SPDIFTX_CR,
+                           SPDIFTX_CR_SWRST | SPDIFTX_CR_FCLR);
+}
+
+
+static const struct snd_soc_dai_ops mchp_spdiftx_dai_ops = {
+       .startup        = mchp_spdiftx_dai_startup,
+       .shutdown       = mchp_spdiftx_dai_shutdown,
+       .trigger        = mchp_spdiftx_trigger,
+       .hw_params      = mchp_spdiftx_hw_params,
+       .hw_free        = mchp_spdiftx_hw_free,
+};
+
+#define MCHP_SPDIFTX_RATES     SNDRV_PCM_RATE_8000_192000
+
+#define MCHP_SPDIFTX_FORMATS   (SNDRV_PCM_FMTBIT_S8 |          \
+                                SNDRV_PCM_FMTBIT_S16_LE |      \
+                                SNDRV_PCM_FMTBIT_U16_BE |      \
+                                SNDRV_PCM_FMTBIT_S18_3LE |     \
+                                SNDRV_PCM_FMTBIT_S18_3BE |     \
+                                SNDRV_PCM_FMTBIT_S20_3LE |     \
+                                SNDRV_PCM_FMTBIT_S20_3BE |     \
+                                SNDRV_PCM_FMTBIT_S24_3LE |     \
+                                SNDRV_PCM_FMTBIT_S24_3BE |     \
+                                SNDRV_PCM_FMTBIT_S24_LE |      \
+                                SNDRV_PCM_FMTBIT_S24_BE |      \
+                                SNDRV_PCM_FMTBIT_S32_LE |      \
+                                SNDRV_PCM_FMTBIT_S32_BE        \
+                                )
+
+static int mchp_spdiftx_info(struct snd_kcontrol *kcontrol,
+                            struct snd_ctl_elem_info *uinfo)
+{
+       uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+       uinfo->count = 1;
+
+       return 0;
+}
+
+static int mchp_spdiftx_cs_get(struct snd_kcontrol *kcontrol,
+                              struct snd_ctl_elem_value *uvalue)
+{
+       unsigned long flags;
+       struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+
+       spin_lock_irqsave(&ctrl->lock, flags);
+       memcpy(uvalue->value.iec958.status, ctrl->ch_stat,
+              sizeof(ctrl->ch_stat));
+       spin_unlock_irqrestore(&ctrl->lock, flags);
+
+       return 0;
+}
+
+static int mchp_spdiftx_cs_put(struct snd_kcontrol *kcontrol,
+                              struct snd_ctl_elem_value *uvalue)
+{
+       unsigned long flags;
+       struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       int changed = 0;
+       int i;
+
+       spin_lock_irqsave(&ctrl->lock, flags);
+       for (i = 0; i < ARRAY_SIZE(ctrl->ch_stat); i++) {
+               if (ctrl->ch_stat[i] != uvalue->value.iec958.status[i])
+                       changed = 1;
+               ctrl->ch_stat[i] = uvalue->value.iec958.status[i];
+       }
+
+       if (changed) {
+               /* don't enable IP while we copy the channel status */
+               if (mchp_spdiftx_is_running(dev)) {
+                       /*
+                        * if SPDIF is running, wait for interrupt to write
+                        * channel status
+                        */
+                       regmap_write(dev->regmap, SPDIFTX_IER,
+                                    SPDIFTX_IR_CSRDY);
+               } else {
+                       mchp_spdiftx_channel_status_write(dev);
+               }
+       }
+       spin_unlock_irqrestore(&ctrl->lock, flags);
+
+       return changed;
+}
+
+static int mchp_spdiftx_cs_mask(struct snd_kcontrol *kcontrol,
+                               struct snd_ctl_elem_value *uvalue)
+{
+       memset(uvalue->value.iec958.status, 0xff,
+              sizeof(uvalue->value.iec958.status));
+
+       return 0;
+}
+
+static int mchp_spdiftx_subcode_get(struct snd_kcontrol *kcontrol,
+                                   struct snd_ctl_elem_value *uvalue)
+{
+       struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       unsigned long flags;
+
+       spin_lock_irqsave(&ctrl->lock, flags);
+       memcpy(uvalue->value.iec958.subcode, ctrl->user_data,
+              sizeof(ctrl->user_data));
+       spin_unlock_irqrestore(&ctrl->lock, flags);
+
+       return 0;
+}
+
+static int mchp_spdiftx_subcode_put(struct snd_kcontrol *kcontrol,
+                                   struct snd_ctl_elem_value *uvalue)
+{
+       unsigned long flags;
+       struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+       struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
+       int changed = 0;
+       int i;
+
+       spin_lock_irqsave(&ctrl->lock, flags);
+       for (i = 0; i < ARRAY_SIZE(ctrl->user_data); i++) {
+               if (ctrl->user_data[i] != uvalue->value.iec958.subcode[i])
+                       changed = 1;
+
+               ctrl->user_data[i] = uvalue->value.iec958.subcode[i];
+       }
+       if (changed) {
+               if (mchp_spdiftx_is_running(dev)) {
+                       /*
+                        * if SPDIF is running, wait for interrupt to write
+                        * user data
+                        */
+                       regmap_write(dev->regmap, SPDIFTX_IER,
+                                    SPDIFTX_IR_UDRDY);
+               } else {
+                       mchp_spdiftx_user_data_write(dev);
+               }
+       }
+       spin_unlock_irqrestore(&ctrl->lock, flags);
+
+       return changed;
+}
+
+static struct snd_kcontrol_new mchp_spdiftx_ctrls[] = {
+       /* Channel status controller */
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+               .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
+               .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+                       SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+               .info = mchp_spdiftx_info,
+               .get = mchp_spdiftx_cs_get,
+               .put = mchp_spdiftx_cs_put,
+       },
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+               .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
+               .access = SNDRV_CTL_ELEM_ACCESS_READ,
+                       SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+               .info = mchp_spdiftx_info,
+               .get = mchp_spdiftx_cs_mask,
+       },
+       /* User bits controller */
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+               .name = "IEC958 Subcode Playback Default",
+               .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+               .info = mchp_spdiftx_info,
+               .get = mchp_spdiftx_subcode_get,
+               .put = mchp_spdiftx_subcode_put,
+       },
+};
+
+static int mchp_spdiftx_dai_probe(struct snd_soc_dai *dai)
+{
+       struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
+
+       snd_soc_dai_init_dma_data(dai, &dev->playback, NULL);
+
+       /* Add controls */
+       snd_soc_add_dai_controls(dai, mchp_spdiftx_ctrls,
+                                ARRAY_SIZE(mchp_spdiftx_ctrls));
+
+       return 0;
+}
+
+static struct snd_soc_dai_driver mchp_spdiftx_dai = {
+       .name = "mchp-spdiftx",
+       .probe  = mchp_spdiftx_dai_probe,
+       .playback = {
+               .stream_name = "S/PDIF TX Playback",
+               .channels_min = 1,
+               .channels_max = 2,
+               .rates = MCHP_SPDIFTX_RATES,
+               .formats = MCHP_SPDIFTX_FORMATS,
+       },
+       .ops = &mchp_spdiftx_dai_ops,
+};
+
+static const struct snd_soc_component_driver mchp_spdiftx_component = {
+       .name           = "mchp-spdiftx",
+};
+
+static const struct of_device_id mchp_spdiftx_dt_ids[] = {
+       {
+               .compatible = "microchip,sama7g5-spdiftx",
+       },
+       { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, mchp_spdiftx_dt_ids);
+static int mchp_spdiftx_probe(struct platform_device *pdev)
+{
+       struct device_node *np = pdev->dev.of_node;
+       const struct of_device_id *match;
+       struct mchp_spdiftx_dev *dev;
+       struct resource *mem;
+       struct regmap *regmap;
+       void __iomem *base;
+       struct mchp_spdiftx_mixer_control *ctrl;
+       int irq;
+       int err;
+
+       /* Get memory for driver data. */
+       dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+       if (!dev)
+               return -ENOMEM;
+
+       /* Get hardware capabilities. */
+       match = of_match_node(mchp_spdiftx_dt_ids, np);
+       if (match)
+               dev->caps = match->data;
+
+       /* Map I/O registers. */
+       base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
+       if (IS_ERR(base))
+               return PTR_ERR(base);
+
+       regmap = devm_regmap_init_mmio(&pdev->dev, base,
+                                      &mchp_spdiftx_regmap_config);
+       if (IS_ERR(regmap))
+               return PTR_ERR(regmap);
+
+       /* Request IRQ */
+       irq = platform_get_irq(pdev, 0);
+       if (irq < 0)
+               return irq;
+
+       err = devm_request_irq(&pdev->dev, irq, mchp_spdiftx_interrupt, 0,
+                              dev_name(&pdev->dev), dev);
+       if (err)
+               return err;
+
+       /* Get the peripheral clock */
+       dev->pclk = devm_clk_get(&pdev->dev, "pclk");
+       if (IS_ERR(dev->pclk)) {
+               err = PTR_ERR(dev->pclk);
+               dev_err(&pdev->dev,
+                       "failed to get the peripheral clock: %d\n", err);
+               return err;
+       }
+
+       /* Get the generic clock */
+       dev->gclk = devm_clk_get(&pdev->dev, "gclk");
+       if (IS_ERR(dev->gclk)) {
+               err = PTR_ERR(dev->gclk);
+               dev_err(&pdev->dev,
+                       "failed to get the PMC generic clock: %d\n", err);
+               return err;
+       }
+
+       ctrl = &dev->control;
+       spin_lock_init(&ctrl->lock);
+
+       /* Init channel status */
+       ctrl->ch_stat[0] = IEC958_AES0_CON_NOT_COPYRIGHT |
+                          IEC958_AES0_CON_EMPHASIS_NONE;
+
+       dev->dev = &pdev->dev;
+       dev->regmap = regmap;
+       platform_set_drvdata(pdev, dev);
+
+       dev->playback.addr = (dma_addr_t)mem->start + SPDIFTX_CDR;
+       dev->playback.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+       err = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+       if (err) {
+               dev_err(&pdev->dev, "failed to register PMC: %d\n", err);
+               return err;
+       }
+
+       err = devm_snd_soc_register_component(&pdev->dev,
+                                             &mchp_spdiftx_component,
+                                             &mchp_spdiftx_dai, 1);
+       if (err) {
+               dev_err(&pdev->dev, "failed to register component: %d\n", err);
+               return err;
+       }
+
+       return 0;
+}
+
+static struct platform_driver mchp_spdiftx_driver = {
+       .probe  = mchp_spdiftx_probe,
+       .driver = {
+               .name   = "mchp_spdiftx",
+               .of_match_table = of_match_ptr(mchp_spdiftx_dt_ids),
+       },
+};
+
+module_platform_driver(mchp_spdiftx_driver);
+
+MODULE_AUTHOR("Codrin Ciubotariu <codrin.ciubota...@microchip.com>");
+MODULE_DESCRIPTION("Microchip S/PDIF TX Controller Driver");
+MODULE_LICENSE("GPL v2");
-- 
2.25.1

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