[PATCH v2 2/2] ASoC: Add initial ZL38060 driver

From: Sven Van Asbroeck
Date: Fri Apr 17 2020 - 18:13:52 EST


The ZL38060 is a "Connected Home Audio Processor" from Microsemi,
which consists of a Digital Signal Processor (DSP), several Digital
Audio Interfaces (DAIs), analog outputs, and a block of 14 GPIOs.

This driver supports only a tiny subset of the chip's functionality
and possible configurations:
- bypass mode (whole dsp block is bypassed)
- chip's I2S DAI routed directly to/from DACs and microphone
- chip's internal clock is driven by a 12 MHz external crystal
- chip's DAI connected to CPU is I2S, and bit + frame clock master
- chip must be strapped for "host boot": in this mode, firmware will
be provided by this driver.

Signed-off-by: Sven Van Asbroeck <TheSven73@xxxxxxxxx>
---

Tree: v5.7-rc1

v1->v2:

Mark Brown:

- fixup comment style at top of file.

- fixup curly braces in if-elseif-else statement.

- explicitly put the chip in reset so it reverts to a known state.

- remove 'mscc,load-firmware' devicetree property, which provided support for
switching between chip bootstrap modes (host boot / auto boot from external
flash).
On reflection, I cannot test correct operation of auto-boot - it involves
interaction with the Bootloader Status Register, and I have no access to an
auto-boot zl38060.
This means the only tested and supported mode will be 'host boot', where the
firmware is programmed by the host CPU (ie. Linux).

- remove amplifier enable gpio. if required, it should be part of the machine
layer.

Sven Van Asbroeck:

- add dapm widgets: DAC1, DAC2, DMICL. Routed to Playback and Capture,
respectively. This is required to drive a microphone amp-enable gpio
from the machine layer.


sound/soc/codecs/Kconfig | 11 +
sound/soc/codecs/Makefile | 2 +
sound/soc/codecs/zl38060.c | 638 +++++++++++++++++++++++++++++++++++++
3 files changed, 651 insertions(+)
create mode 100644 sound/soc/codecs/zl38060.c

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index e6a0c5d05fa5..7cb032757d32 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -272,6 +272,7 @@ config SND_SOC_ALL_CODECS
imply SND_SOC_WM9712
imply SND_SOC_WM9713
imply SND_SOC_WSA881X
+ imply SND_SOC_ZL38060
help
Normally ASoC codec drivers are only built if a machine driver which
uses them is also built since they are only usable with a machine
@@ -1642,6 +1643,16 @@ config SND_SOC_WSA881X
This enables support for Qualcomm WSA8810/WSA8815 Class-D
Smart Speaker Amplifier.

+config SND_SOC_ZL38060
+ tristate "Microsemi ZL38060 Connected Home Audio Processor"
+ depends on SPI_MASTER
+ select GPIOLIB
+ select REGMAP
+ help
+ Support for ZL38060 Connected Home Audio Processor from Microsemi,
+ which consists of a Digital Signal Processor (DSP), several Digital
+ Audio Interfaces (DAIs), analog outputs, and a block of 14 GPIOs.
+
config SND_SOC_ZX_AUD96P22
tristate "ZTE ZX AUD96P22 CODEC"
depends on I2C
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index 03533157cda6..a603532c7af5 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -288,6 +288,7 @@ snd-soc-wm9712-objs := wm9712.o
snd-soc-wm9713-objs := wm9713.o
snd-soc-wm-hubs-objs := wm_hubs.o
snd-soc-wsa881x-objs := wsa881x.o
+snd-soc-zl38060-objs := zl38060.o
snd-soc-zx-aud96p22-objs := zx_aud96p22.o
# Amp
snd-soc-max9877-objs := max9877.o
@@ -588,6 +589,7 @@ obj-$(CONFIG_SND_SOC_WM9713) += snd-soc-wm9713.o
obj-$(CONFIG_SND_SOC_WM_ADSP) += snd-soc-wm-adsp.o
obj-$(CONFIG_SND_SOC_WM_HUBS) += snd-soc-wm-hubs.o
obj-$(CONFIG_SND_SOC_WSA881X) += snd-soc-wsa881x.o
+obj-$(CONFIG_SND_SOC_ZL38060) += snd-soc-zl38060.o
obj-$(CONFIG_SND_SOC_ZX_AUD96P22) += snd-soc-zx-aud96p22.o

# Amp
diff --git a/sound/soc/codecs/zl38060.c b/sound/soc/codecs/zl38060.c
new file mode 100644
index 000000000000..927ad849ad2d
--- /dev/null
+++ b/sound/soc/codecs/zl38060.c
@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Codec driver for Microsemi ZL38060 Connected Home Audio Processor.
+//
+// Copyright(c) 2020 Sven Van Asbroeck
+
+// The ZL38060 is very flexible and configurable. This driver implements only a
+// tiny subset of the chip's possible configurations:
+//
+// - DSP block bypassed: DAI routed straight to DACs
+// microphone routed straight to DAI
+// - chip's internal clock is driven by a 12 MHz external crystal
+// - chip's DAI connected to CPU is I2S, and bit + frame clock master
+// - chip must be strapped for "host boot": in this mode, firmware will be
+// provided by this driver.
+
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/property.h>
+#include <linux/spi/spi.h>
+#include <linux/regmap.h>
+#include <linux/module.h>
+#include <linux/ihex.h>
+
+#include <sound/pcm_params.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+
+#define DRV_NAME "zl38060"
+
+#define ZL38_RATES (SNDRV_PCM_RATE_8000 |\
+ SNDRV_PCM_RATE_16000 |\
+ SNDRV_PCM_RATE_48000)
+#define ZL38_FORMATS SNDRV_PCM_FMTBIT_S16_LE
+
+#define HBI_FIRMWARE_PAGE 0xFF
+#define ZL38_MAX_RAW_XFER 0x100
+
+#define REG_TDMA_CFG_CLK 0x0262
+#define CFG_CLK_PCLK_SHIFT 4
+#define CFG_CLK_PCLK_MASK (0x7ff << CFG_CLK_PCLK_SHIFT)
+#define CFG_CLK_PCLK(bits) ((bits - 1) << CFG_CLK_PCLK_SHIFT)
+#define CFG_CLK_MASTER BIT(15)
+#define CFG_CLK_FSRATE_MASK 0x7
+#define CFG_CLK_FSRATE_8KHZ 0x1
+#define CFG_CLK_FSRATE_16KHZ 0x2
+#define CFG_CLK_FSRATE_48KHZ 0x6
+
+#define REG_CLK_CFG 0x0016
+#define CLK_CFG_SOURCE_XTAL BIT(15)
+
+#define REG_CLK_STATUS 0x0014
+#define CLK_STATUS_HWRST BIT(0)
+
+#define REG_PARAM_RESULT 0x0034
+#define PARAM_RESULT_READY 0xD3D3
+
+#define REG_PG255_BASE_HI 0x000C
+#define REG_PG255_OFFS(addr) ((HBI_FIRMWARE_PAGE << 8) | (addr & 0xFF))
+#define REG_FWR_EXEC 0x012C
+
+#define REG_CMD 0x0032
+#define REG_HW_REV 0x0020
+#define REG_FW_PROD 0x0022
+#define REG_FW_REV 0x0024
+
+#define REG_SEMA_FLAGS 0x0006
+#define SEMA_FLAGS_BOOT_CMD BIT(0)
+#define SEMA_FLAGS_APP_REBOOT BIT(1)
+
+#define REG_HW_REV 0x0020
+#define REG_FW_PROD 0x0022
+#define REG_FW_REV 0x0024
+#define REG_GPIO_DIR 0x02DC
+#define REG_GPIO_DAT 0x02DA
+
+#define BOOTCMD_LOAD_COMPLETE 0x000D
+#define BOOTCMD_FW_GO 0x0008
+
+#define FIRMWARE_MAJOR 2
+#define FIRMWARE_MINOR 2
+
+struct zl38_codec_priv {
+ struct device *dev;
+ struct regmap *regmap;
+ bool is_stream_in_use[2];
+ struct gpio_chip *gpio_chip;
+};
+
+static int zl38_fw_issue_command(struct regmap *regmap, u16 cmd)
+{
+ unsigned int val;
+ int err;
+
+ err = regmap_read_poll_timeout(regmap, REG_SEMA_FLAGS, val,
+ !(val & SEMA_FLAGS_BOOT_CMD), 10000,
+ 10000 * 100);
+ if (err)
+ return err;
+ err = regmap_write(regmap, REG_CMD, cmd);
+ if (err)
+ return err;
+ err = regmap_update_bits(regmap, REG_SEMA_FLAGS, SEMA_FLAGS_BOOT_CMD,
+ SEMA_FLAGS_BOOT_CMD);
+ if (err)
+ return err;
+
+ return regmap_read_poll_timeout(regmap, REG_CMD, val, !val, 10000,
+ 10000 * 100);
+}
+
+static int zl38_fw_go(struct regmap *regmap)
+{
+ int err;
+
+ err = zl38_fw_issue_command(regmap, BOOTCMD_LOAD_COMPLETE);
+ if (err)
+ return err;
+
+ return zl38_fw_issue_command(regmap, BOOTCMD_FW_GO);
+}
+
+static int zl38_fw_enter_boot_mode(struct regmap *regmap)
+{
+ unsigned int val;
+ int err;
+
+ err = regmap_update_bits(regmap, REG_CLK_STATUS, CLK_STATUS_HWRST,
+ CLK_STATUS_HWRST);
+ if (err)
+ return err;
+
+ return regmap_read_poll_timeout(regmap, REG_PARAM_RESULT, val,
+ val == PARAM_RESULT_READY, 1000, 50000);
+}
+
+static int
+zl38_fw_send_data(struct regmap *regmap, u32 addr, const void *data, u16 len)
+{
+ __be32 addr_base = cpu_to_be32(addr & ~0xFF);
+ int err;
+
+ err = regmap_raw_write(regmap, REG_PG255_BASE_HI, &addr_base,
+ sizeof(addr_base));
+ if (err)
+ return err;
+ return regmap_raw_write(regmap, REG_PG255_OFFS(addr), data, len);
+}
+
+static int zl38_fw_send_xaddr(struct regmap *regmap, const void *data)
+{
+ /* execution address from ihex: 32-bit little endian.
+ * device register expects 32-bit big endian.
+ */
+ u32 addr = le32_to_cpup(data);
+ __be32 baddr = cpu_to_be32(addr);
+
+ return regmap_raw_write(regmap, REG_FWR_EXEC, &baddr, sizeof(baddr));
+}
+
+static int zl38_load_firmware(struct device *dev, struct regmap *regmap)
+{
+ const struct ihex_binrec *rec;
+ const struct firmware *fw;
+ u32 addr;
+ u16 len;
+ int err;
+
+ /* how to get this firmware:
+ * 1. request and download chip firmware from Microsemi
+ * (provided by Microsemi in srec format)
+ * 2. convert downloaded firmware from srec to ihex. Simple tool:
+ * https://gitlab.com/TheSven73/s3-to-irec
+ * 3. convert ihex to binary (.fw) using ihex2fw tool which is included
+ * with the Linux kernel sources
+ */
+ err = request_ihex_firmware(&fw, "zl38060.fw", dev);
+ if (err)
+ return err;
+ err = zl38_fw_enter_boot_mode(regmap);
+ if (err)
+ goto out;
+ rec = (const struct ihex_binrec *)fw->data;
+ while (rec) {
+ addr = be32_to_cpu(rec->addr);
+ len = be16_to_cpu(rec->len);
+ if (addr) {
+ /* regular data ihex record */
+ err = zl38_fw_send_data(regmap, addr, rec->data, len);
+ } else if (len == 4) {
+ /* execution address ihex record */
+ err = zl38_fw_send_xaddr(regmap, rec->data);
+ } else {
+ err = -EINVAL;
+ }
+ if (err)
+ goto out;
+ /* next ! */
+ rec = ihex_next_binrec(rec);
+ }
+ err = zl38_fw_go(regmap);
+
+out:
+ release_firmware(fw);
+ return err;
+}
+
+
+static int zl38_software_reset(struct regmap *regmap)
+{
+ unsigned int val;
+ int err;
+
+ err = regmap_update_bits(regmap, REG_SEMA_FLAGS, SEMA_FLAGS_APP_REBOOT,
+ SEMA_FLAGS_APP_REBOOT);
+ if (err)
+ return err;
+
+ /* wait for host bus interface to settle.
+ * Not sure if this is required: Microsemi's vendor driver does this,
+ * but the firmware manual does not mention it. Leave it in, there's
+ * little downside, apart from a slower reset.
+ */
+ msleep(50);
+
+ return regmap_read_poll_timeout(regmap, REG_SEMA_FLAGS, val,
+ !(val & SEMA_FLAGS_APP_REBOOT), 10000,
+ 10000 * 100);
+}
+
+static int zl38_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+ struct zl38_codec_priv *priv = snd_soc_dai_get_drvdata(dai);
+ int err;
+
+ switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ /* firmware default is normal i2s */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+ case SND_SOC_DAIFMT_NB_NF:
+ /* firmware default is normal bitclock and frame */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+ case SND_SOC_DAIFMT_CBM_CFM:
+ /* always 32 bits per frame (= 16 bits/channel, 2 channels) */
+ err = regmap_update_bits(priv->regmap, REG_TDMA_CFG_CLK,
+ CFG_CLK_MASTER | CFG_CLK_PCLK_MASK,
+ CFG_CLK_MASTER | CFG_CLK_PCLK(32));
+ if (err)
+ return err;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int zl38_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params,
+ struct snd_soc_dai *dai)
+{
+ struct zl38_codec_priv *priv = snd_soc_dai_get_drvdata(dai);
+ bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
+ unsigned int fsrate;
+ int err;
+
+ /* We cannot change hw_params while the dai is already in use - the
+ * software reset will corrupt the audio. However, this is not required,
+ * as the chip's TDM buses are fully symmetric, which mandates identical
+ * rates, channels, and samplebits for record and playback.
+ */
+ if (priv->is_stream_in_use[!tx])
+ goto skip_setup;
+
+ switch (params_rate(params)) {
+ case 8000:
+ fsrate = CFG_CLK_FSRATE_8KHZ;
+ break;
+ case 16000:
+ fsrate = CFG_CLK_FSRATE_16KHZ;
+ break;
+ case 48000:
+ fsrate = CFG_CLK_FSRATE_48KHZ;
+ break;
+ default:
+ return -EINVAL;
+ };
+
+ err = regmap_update_bits(priv->regmap, REG_TDMA_CFG_CLK,
+ CFG_CLK_FSRATE_MASK, fsrate);
+ if (err)
+ return err;
+
+ /* chip requires a software reset to apply audio register changes */
+ err = zl38_software_reset(priv->regmap);
+ if (err)
+ return err;
+
+skip_setup:
+ priv->is_stream_in_use[tx] = true;
+
+ return 0;
+}
+
+static int zl38_hw_free(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct zl38_codec_priv *priv = snd_soc_dai_get_drvdata(dai);
+ bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
+
+ priv->is_stream_in_use[tx] = false;
+
+ return 0;
+}
+
+/* stereo bypass with no AEC */
+static const struct reg_sequence cp_config_stereo_bypass[] = {
+ /* interconnects must be programmed first */
+ { 0x0210, 0x0005 }, /* DAC1 in <= I2S1-L */
+ { 0x0212, 0x0006 }, /* DAC2 in <= I2S1-R */
+ { 0x0214, 0x0001 }, /* I2S1-L in <= MIC1 */
+ { 0x0216, 0x0001 }, /* I2S1-R in <= MIC1 */
+ { 0x0224, 0x0000 }, /* AEC-S in <= n/a */
+ { 0x0226, 0x0000 }, /* AEC-R in <= n/a */
+ /* output enables must be programmed next */
+ { 0x0202, 0x000F }, /* enable I2S1 + DAC */
+};
+
+static const struct snd_soc_dai_ops zl38_dai_ops = {
+ .set_fmt = zl38_set_fmt,
+ .hw_params = zl38_hw_params,
+ .hw_free = zl38_hw_free,
+};
+
+static struct snd_soc_dai_driver zl38_dai = {
+ .name = "zl38060-tdma",
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = ZL38_RATES,
+ .formats = ZL38_FORMATS,
+ },
+ .capture = {
+ .stream_name = "Capture",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = ZL38_RATES,
+ .formats = ZL38_FORMATS,
+ },
+ .ops = &zl38_dai_ops,
+ .symmetric_rates = 1,
+ .symmetric_samplebits = 1,
+ .symmetric_channels = 1,
+};
+
+static const struct snd_soc_dapm_widget zl38_dapm_widgets[] = {
+ SND_SOC_DAPM_OUTPUT("DAC1"),
+ SND_SOC_DAPM_OUTPUT("DAC2"),
+
+ SND_SOC_DAPM_INPUT("DMICL"),
+};
+
+static const struct snd_soc_dapm_route zl38_dapm_routes[] = {
+ { "DAC1", NULL, "Playback" },
+ { "DAC2", NULL, "Playback" },
+
+ { "Capture", NULL, "DMICL" },
+};
+
+static const struct snd_soc_component_driver zl38_component_dev = {
+ .dapm_widgets = zl38_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(zl38_dapm_widgets),
+ .dapm_routes = zl38_dapm_routes,
+ .num_dapm_routes = ARRAY_SIZE(zl38_dapm_routes),
+ .endianness = 1,
+ .non_legacy_dai_naming = 1,
+};
+
+static void chip_gpio_set(struct gpio_chip *c, unsigned int offset, int val)
+{
+ struct regmap *regmap = gpiochip_get_data(c);
+ unsigned int mask = BIT(offset);
+
+ regmap_update_bits(regmap, REG_GPIO_DAT, mask, val ? mask : 0);
+}
+
+static int chip_gpio_get(struct gpio_chip *c, unsigned int offset)
+{
+ struct regmap *regmap = gpiochip_get_data(c);
+ unsigned int mask = BIT(offset);
+ unsigned int val;
+ int err;
+
+ err = regmap_read(regmap, REG_GPIO_DAT, &val);
+ if (err)
+ return err;
+
+ return !!(val & mask);
+}
+
+static int chip_direction_input(struct gpio_chip *c, unsigned int offset)
+{
+ struct regmap *regmap = gpiochip_get_data(c);
+ unsigned int mask = BIT(offset);
+
+ return regmap_update_bits(regmap, REG_GPIO_DIR, mask, 0);
+}
+
+static int
+chip_direction_output(struct gpio_chip *c, unsigned int offset, int val)
+{
+ struct regmap *regmap = gpiochip_get_data(c);
+ unsigned int mask = BIT(offset);
+
+ chip_gpio_set(c, offset, val);
+ return regmap_update_bits(regmap, REG_GPIO_DIR, mask, mask);
+}
+
+static const struct gpio_chip template_chip = {
+ .owner = THIS_MODULE,
+ .label = DRV_NAME,
+
+ .base = -1,
+ .ngpio = 14,
+ .direction_input = chip_direction_input,
+ .direction_output = chip_direction_output,
+ .get = chip_gpio_get,
+ .set = chip_gpio_set,
+
+ .can_sleep = true,
+};
+
+static int zl38_check_revision(struct device *dev, struct regmap *regmap)
+{
+ unsigned int hwrev, fwprod, fwrev;
+ int fw_major, fw_minor, fw_micro;
+ int err;
+
+ err = regmap_read(regmap, REG_HW_REV, &hwrev);
+ if (err)
+ return err;
+ err = regmap_read(regmap, REG_FW_PROD, &fwprod);
+ if (err)
+ return err;
+ err = regmap_read(regmap, REG_FW_REV, &fwrev);
+ if (err)
+ return err;
+
+ fw_major = (fwrev >> 12) & 0xF;
+ fw_minor = (fwrev >> 8) & 0xF;
+ fw_micro = fwrev & 0xFF;
+ dev_info(dev, "hw rev 0x%x, fw product code %d, firmware rev %d.%d.%d",
+ hwrev & 0x1F, fwprod, fw_major, fw_minor, fw_micro);
+
+ if (fw_major != FIRMWARE_MAJOR || fw_minor < FIRMWARE_MINOR) {
+ dev_err(dev, "unsupported firmware. driver supports %d.%d",
+ FIRMWARE_MAJOR, FIRMWARE_MINOR);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int zl38_bus_read(void *context,
+ const void *reg_buf, size_t reg_size,
+ void *val_buf, size_t val_size)
+{
+ struct spi_device *spi = context;
+ const u8 *reg_buf8 = reg_buf;
+ size_t len = 0;
+ u8 offs, page;
+ u8 txbuf[4];
+
+ if (reg_size != 2 || val_size > ZL38_MAX_RAW_XFER)
+ return -EINVAL;
+
+ offs = reg_buf8[1] >> 1;
+ page = reg_buf8[0];
+
+ if (page) {
+ txbuf[len++] = 0xFE;
+ txbuf[len++] = page == HBI_FIRMWARE_PAGE ? 0xFF : page - 1;
+ txbuf[len++] = offs;
+ txbuf[len++] = val_size / 2 - 1;
+ } else {
+ txbuf[len++] = offs | 0x80;
+ txbuf[len++] = val_size / 2 - 1;
+ }
+
+ return spi_write_then_read(spi, txbuf, len, val_buf, val_size);
+}
+
+static int zl38_bus_write(void *context, const void *data, size_t count)
+{
+ struct spi_device *spi = context;
+ u8 buf[4 + ZL38_MAX_RAW_XFER];
+ size_t val_len, len = 0;
+ const u8 *data8 = data;
+ u8 offs, page;
+
+ if (count > (2 + ZL38_MAX_RAW_XFER) || count < 4)
+ return -EINVAL;
+ val_len = count - 2;
+ offs = data8[1] >> 1;
+ page = data8[0];
+
+ if (page) {
+ buf[len++] = 0xFE;
+ buf[len++] = page == HBI_FIRMWARE_PAGE ? 0xFF : page - 1;
+ buf[len++] = offs;
+ buf[len++] = (val_len / 2 - 1) | 0x80;
+ } else {
+ buf[len++] = offs | 0x80;
+ buf[len++] = (val_len / 2 - 1) | 0x80;
+ }
+ memcpy(buf + len, data8 + 2, val_len);
+ len += val_len;
+
+ return spi_write(spi, buf, len);
+}
+
+static const struct regmap_bus zl38_regmap_bus = {
+ .read = zl38_bus_read,
+ .write = zl38_bus_write,
+ .max_raw_write = ZL38_MAX_RAW_XFER,
+ .max_raw_read = ZL38_MAX_RAW_XFER,
+};
+
+static const struct regmap_config zl38_regmap_conf = {
+ .reg_bits = 16,
+ .val_bits = 16,
+ .reg_stride = 2,
+ .use_single_read = true,
+ .use_single_write = true,
+};
+
+static int zl38_spi_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct zl38_codec_priv *priv;
+ struct gpio_desc *reset_gpio;
+ int err;
+
+ /* get the chip to a known state by putting it in reset */
+ reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(reset_gpio))
+ return PTR_ERR(reset_gpio);
+ if (reset_gpio) {
+ /* datasheet: need > 10us for a digital + analog reset */
+ usleep_range(15, 50);
+ /* take the chip out of reset */
+ gpiod_set_value_cansleep(reset_gpio, 0);
+ /* datasheet: need > 3ms for digital section to become stable */
+ usleep_range(3000, 10000);
+ }
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+ dev_set_drvdata(dev, priv);
+ priv->regmap = devm_regmap_init(dev, &zl38_regmap_bus, spi,
+ &zl38_regmap_conf);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ err = zl38_load_firmware(dev, priv->regmap);
+ if (err)
+ return err;
+
+ err = zl38_check_revision(dev, priv->regmap);
+ if (err)
+ return err;
+
+ priv->gpio_chip = devm_kmemdup(dev, &template_chip,
+ sizeof(template_chip), GFP_KERNEL);
+ if (!priv->gpio_chip)
+ return -ENOMEM;
+#ifdef CONFIG_OF_GPIO
+ priv->gpio_chip->of_node = dev->of_node;
+#endif
+ err = devm_gpiochip_add_data(dev, priv->gpio_chip, priv->regmap);
+ if (err)
+ return err;
+
+ /* setup the cross-point switch for stereo bypass */
+ err = regmap_multi_reg_write(priv->regmap, cp_config_stereo_bypass,
+ ARRAY_SIZE(cp_config_stereo_bypass));
+ if (err)
+ return err;
+ /* setup for 12MHz crystal connected to the chip */
+ err = regmap_update_bits(priv->regmap, REG_CLK_CFG, CLK_CFG_SOURCE_XTAL,
+ CLK_CFG_SOURCE_XTAL);
+ if (err)
+ return err;
+
+ return devm_snd_soc_register_component(dev, &zl38_component_dev,
+ &zl38_dai, 1);
+}
+
+static const struct of_device_id zl38_dt_ids[] = {
+ { .compatible = "mscc,zl38060", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, zl38_dt_ids);
+
+static const struct spi_device_id zl38_spi_ids[] = {
+ { "zl38060", 0 },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(spi, zl38_spi_ids);
+
+static struct spi_driver zl38060_spi_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = of_match_ptr(zl38_dt_ids),
+ },
+ .probe = zl38_spi_probe,
+ .id_table = zl38_spi_ids,
+};
+module_spi_driver(zl38060_spi_driver);
+
+MODULE_DESCRIPTION("ASoC ZL38060 driver");
+MODULE_AUTHOR("Sven Van Asbroeck <TheSven73@xxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.17.1