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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /sound/soc/codecs/cs4270.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sound/soc/codecs/cs4270.c')
-rw-r--r--sound/soc/codecs/cs4270.c762
1 files changed, 762 insertions, 0 deletions
diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
new file mode 100644
index 000000000..1b640d823
--- /dev/null
+++ b/sound/soc/codecs/cs4270.c
@@ -0,0 +1,762 @@
+/*
+ * CS4270 ALSA SoC (ASoC) codec driver
+ *
+ * Author: Timur Tabi <timur@freescale.com>
+ *
+ * Copyright 2007-2009 Freescale Semiconductor, Inc. This file is licensed
+ * under the terms of the GNU General Public License version 2. This
+ * program is licensed "as is" without any warranty of any kind, whether
+ * express or implied.
+ *
+ * This is an ASoC device driver for the Cirrus Logic CS4270 codec.
+ *
+ * Current features/limitations:
+ *
+ * - Software mode is supported. Stand-alone mode is not supported.
+ * - Only I2C is supported, not SPI
+ * - Support for master and slave mode
+ * - The machine driver's 'startup' function must call
+ * cs4270_set_dai_sysclk() with the value of MCLK.
+ * - Only I2S and left-justified modes are supported
+ * - Power management is supported
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/soc.h>
+#include <sound/initval.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/regulator/consumer.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of_device.h>
+
+#define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE | \
+ SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S20_3LE | \
+ SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+/* CS4270 registers addresses */
+#define CS4270_CHIPID 0x01 /* Chip ID */
+#define CS4270_PWRCTL 0x02 /* Power Control */
+#define CS4270_MODE 0x03 /* Mode Control */
+#define CS4270_FORMAT 0x04 /* Serial Format, ADC/DAC Control */
+#define CS4270_TRANS 0x05 /* Transition Control */
+#define CS4270_MUTE 0x06 /* Mute Control */
+#define CS4270_VOLA 0x07 /* DAC Channel A Volume Control */
+#define CS4270_VOLB 0x08 /* DAC Channel B Volume Control */
+
+#define CS4270_FIRSTREG 0x01
+#define CS4270_LASTREG 0x08
+#define CS4270_NUMREGS (CS4270_LASTREG - CS4270_FIRSTREG + 1)
+#define CS4270_I2C_INCR 0x80
+
+/* Bit masks for the CS4270 registers */
+#define CS4270_CHIPID_ID 0xF0
+#define CS4270_CHIPID_REV 0x0F
+#define CS4270_PWRCTL_FREEZE 0x80
+#define CS4270_PWRCTL_PDN_ADC 0x20
+#define CS4270_PWRCTL_PDN_DAC 0x02
+#define CS4270_PWRCTL_PDN 0x01
+#define CS4270_PWRCTL_PDN_ALL \
+ (CS4270_PWRCTL_PDN_ADC | CS4270_PWRCTL_PDN_DAC | CS4270_PWRCTL_PDN)
+#define CS4270_MODE_SPEED_MASK 0x30
+#define CS4270_MODE_1X 0x00
+#define CS4270_MODE_2X 0x10
+#define CS4270_MODE_4X 0x20
+#define CS4270_MODE_SLAVE 0x30
+#define CS4270_MODE_DIV_MASK 0x0E
+#define CS4270_MODE_DIV1 0x00
+#define CS4270_MODE_DIV15 0x02
+#define CS4270_MODE_DIV2 0x04
+#define CS4270_MODE_DIV3 0x06
+#define CS4270_MODE_DIV4 0x08
+#define CS4270_MODE_POPGUARD 0x01
+#define CS4270_FORMAT_FREEZE_A 0x80
+#define CS4270_FORMAT_FREEZE_B 0x40
+#define CS4270_FORMAT_LOOPBACK 0x20
+#define CS4270_FORMAT_DAC_MASK 0x18
+#define CS4270_FORMAT_DAC_LJ 0x00
+#define CS4270_FORMAT_DAC_I2S 0x08
+#define CS4270_FORMAT_DAC_RJ16 0x18
+#define CS4270_FORMAT_DAC_RJ24 0x10
+#define CS4270_FORMAT_ADC_MASK 0x01
+#define CS4270_FORMAT_ADC_LJ 0x00
+#define CS4270_FORMAT_ADC_I2S 0x01
+#define CS4270_TRANS_ONE_VOL 0x80
+#define CS4270_TRANS_SOFT 0x40
+#define CS4270_TRANS_ZERO 0x20
+#define CS4270_TRANS_INV_ADC_A 0x08
+#define CS4270_TRANS_INV_ADC_B 0x10
+#define CS4270_TRANS_INV_DAC_A 0x02
+#define CS4270_TRANS_INV_DAC_B 0x04
+#define CS4270_TRANS_DEEMPH 0x01
+#define CS4270_MUTE_AUTO 0x20
+#define CS4270_MUTE_ADC_A 0x08
+#define CS4270_MUTE_ADC_B 0x10
+#define CS4270_MUTE_POLARITY 0x04
+#define CS4270_MUTE_DAC_A 0x01
+#define CS4270_MUTE_DAC_B 0x02
+
+/* Power-on default values for the registers
+ *
+ * This array contains the power-on default values of the registers, with the
+ * exception of the "CHIPID" register (01h). The lower four bits of that
+ * register contain the hardware revision, so it is treated as volatile.
+ */
+static const struct reg_default cs4270_reg_defaults[] = {
+ { 2, 0x00 },
+ { 3, 0x30 },
+ { 4, 0x00 },
+ { 5, 0x60 },
+ { 6, 0x20 },
+ { 7, 0x00 },
+ { 8, 0x00 },
+};
+
+static const char *supply_names[] = {
+ "va", "vd", "vlc"
+};
+
+/* Private data for the CS4270 */
+struct cs4270_private {
+ struct regmap *regmap;
+ unsigned int mclk; /* Input frequency of the MCLK pin */
+ unsigned int mode; /* The mode (I2S or left-justified) */
+ unsigned int slave_mode;
+ unsigned int manual_mute;
+
+ /* power domain regulators */
+ struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+
+ /* reset gpio */
+ struct gpio_desc *reset_gpio;
+};
+
+static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
+SND_SOC_DAPM_INPUT("AINL"),
+SND_SOC_DAPM_INPUT("AINR"),
+
+SND_SOC_DAPM_OUTPUT("AOUTL"),
+SND_SOC_DAPM_OUTPUT("AOUTR"),
+};
+
+static const struct snd_soc_dapm_route cs4270_dapm_routes[] = {
+ { "Capture", NULL, "AINL" },
+ { "Capture", NULL, "AINR" },
+
+ { "AOUTL", NULL, "Playback" },
+ { "AOUTR", NULL, "Playback" },
+};
+
+/**
+ * struct cs4270_mode_ratios - clock ratio tables
+ * @ratio: the ratio of MCLK to the sample rate
+ * @speed_mode: the Speed Mode bits to set in the Mode Control register for
+ * this ratio
+ * @mclk: the Ratio Select bits to set in the Mode Control register for this
+ * ratio
+ *
+ * The data for this chart is taken from Table 5 of the CS4270 reference
+ * manual.
+ *
+ * This table is used to determine how to program the Mode Control register.
+ * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
+ * rates the CS4270 currently supports.
+ *
+ * @speed_mode is the corresponding bit pattern to be written to the
+ * MODE bits of the Mode Control Register
+ *
+ * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
+ * the Mode Control Register.
+ *
+ * In situations where a single ratio is represented by multiple speed
+ * modes, we favor the slowest speed. E.g, for a ratio of 128, we pick
+ * double-speed instead of quad-speed. However, the CS4270 errata states
+ * that divide-By-1.5 can cause failures, so we avoid that mode where
+ * possible.
+ *
+ * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
+ * work if Vd is 3.3V. If this effects you, select the
+ * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
+ * never select any sample rates that require divide-by-1.5.
+ */
+struct cs4270_mode_ratios {
+ unsigned int ratio;
+ u8 speed_mode;
+ u8 mclk;
+};
+
+static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
+ {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
+#ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
+ {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
+#endif
+ {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
+ {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
+ {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
+ {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
+ {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
+ {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
+ {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
+};
+
+/* The number of MCLK/LRCK ratios supported by the CS4270 */
+#define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
+
+static bool cs4270_reg_is_readable(struct device *dev, unsigned int reg)
+{
+ return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG);
+}
+
+static bool cs4270_reg_is_volatile(struct device *dev, unsigned int reg)
+{
+ /* Unreadable registers are considered volatile */
+ if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
+ return true;
+
+ return reg == CS4270_CHIPID;
+}
+
+/**
+ * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
+ * @codec_dai: the codec DAI
+ * @clk_id: the clock ID (ignored)
+ * @freq: the MCLK input frequency
+ * @dir: the clock direction (ignored)
+ *
+ * This function is used to tell the codec driver what the input MCLK
+ * frequency is.
+ *
+ * The value of MCLK is used to determine which sample rates are supported
+ * by the CS4270. The ratio of MCLK / Fs must be equal to one of nine
+ * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
+ *
+ * This function calculates the nine ratios and determines which ones match
+ * a standard sample rate. If there's a match, then it is added to the list
+ * of supported sample rates.
+ *
+ * This function must be called by the machine driver's 'startup' function,
+ * otherwise the list of supported sample rates will not be available in
+ * time for ALSA.
+ *
+ * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
+ * theoretically possible sample rates to be enabled. Call it again with a
+ * proper value set one the external clock is set (most probably you would do
+ * that from a machine's driver 'hw_param' hook.
+ */
+static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
+ int clk_id, unsigned int freq, int dir)
+{
+ struct snd_soc_component *component = codec_dai->component;
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+
+ cs4270->mclk = freq;
+ return 0;
+}
+
+/**
+ * cs4270_set_dai_fmt - configure the codec for the selected audio format
+ * @codec_dai: the codec DAI
+ * @format: a SND_SOC_DAIFMT_x value indicating the data format
+ *
+ * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
+ * codec accordingly.
+ *
+ * Currently, this function only supports SND_SOC_DAIFMT_I2S and
+ * SND_SOC_DAIFMT_LEFT_J. The CS4270 codec also supports right-justified
+ * data for playback only, but ASoC currently does not support different
+ * formats for playback vs. record.
+ */
+static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
+ unsigned int format)
+{
+ struct snd_soc_component *component = codec_dai->component;
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+
+ /* set DAI format */
+ switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ case SND_SOC_DAIFMT_LEFT_J:
+ cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
+ break;
+ default:
+ dev_err(component->dev, "invalid dai format\n");
+ return -EINVAL;
+ }
+
+ /* set master/slave audio interface */
+ switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
+ case SND_SOC_DAIFMT_CBS_CFS:
+ cs4270->slave_mode = 1;
+ break;
+ case SND_SOC_DAIFMT_CBM_CFM:
+ cs4270->slave_mode = 0;
+ break;
+ default:
+ /* all other modes are unsupported by the hardware */
+ dev_err(component->dev, "Unknown master/slave configuration\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * cs4270_hw_params - program the CS4270 with the given hardware parameters.
+ * @substream: the audio stream
+ * @params: the hardware parameters to set
+ * @dai: the SOC DAI (ignored)
+ *
+ * This function programs the hardware with the values provided.
+ * Specifically, the sample rate and the data format.
+ *
+ * The .ops functions are used to provide board-specific data, like input
+ * frequencies, to this driver. This function takes that information,
+ * combines it with the hardware parameters provided, and programs the
+ * hardware accordingly.
+ */
+static int cs4270_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params,
+ struct snd_soc_dai *dai)
+{
+ struct snd_soc_component *component = dai->component;
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int ret;
+ unsigned int i;
+ unsigned int rate;
+ unsigned int ratio;
+ int reg;
+
+ /* Figure out which MCLK/LRCK ratio to use */
+
+ rate = params_rate(params); /* Sampling rate, in Hz */
+ ratio = cs4270->mclk / rate; /* MCLK/LRCK ratio */
+
+ for (i = 0; i < NUM_MCLK_RATIOS; i++) {
+ if (cs4270_mode_ratios[i].ratio == ratio)
+ break;
+ }
+
+ if (i == NUM_MCLK_RATIOS) {
+ /* We did not find a matching ratio */
+ dev_err(component->dev, "could not find matching ratio\n");
+ return -EINVAL;
+ }
+
+ /* Set the sample rate */
+
+ reg = snd_soc_component_read(component, CS4270_MODE);
+ reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
+ reg |= cs4270_mode_ratios[i].mclk;
+
+ if (cs4270->slave_mode)
+ reg |= CS4270_MODE_SLAVE;
+ else
+ reg |= cs4270_mode_ratios[i].speed_mode;
+
+ ret = snd_soc_component_write(component, CS4270_MODE, reg);
+ if (ret < 0) {
+ dev_err(component->dev, "i2c write failed\n");
+ return ret;
+ }
+
+ /* Set the DAI format */
+
+ reg = snd_soc_component_read(component, CS4270_FORMAT);
+ reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
+
+ switch (cs4270->mode) {
+ case SND_SOC_DAIFMT_I2S:
+ reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
+ break;
+ case SND_SOC_DAIFMT_LEFT_J:
+ reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
+ break;
+ default:
+ dev_err(component->dev, "unknown dai format\n");
+ return -EINVAL;
+ }
+
+ ret = snd_soc_component_write(component, CS4270_FORMAT, reg);
+ if (ret < 0) {
+ dev_err(component->dev, "i2c write failed\n");
+ return ret;
+ }
+
+ return ret;
+}
+
+/**
+ * cs4270_dai_mute - enable/disable the CS4270 external mute
+ * @dai: the SOC DAI
+ * @mute: 0 = disable mute, 1 = enable mute
+ * @direction: (ignored)
+ *
+ * This function toggles the mute bits in the MUTE register. The CS4270's
+ * mute capability is intended for external muting circuitry, so if the
+ * board does not have the MUTEA or MUTEB pins connected to such circuitry,
+ * then this function will do nothing.
+ */
+static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute, int direction)
+{
+ struct snd_soc_component *component = dai->component;
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int reg6;
+
+ reg6 = snd_soc_component_read(component, CS4270_MUTE);
+
+ if (mute)
+ reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
+ else {
+ reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
+ reg6 |= cs4270->manual_mute;
+ }
+
+ return snd_soc_component_write(component, CS4270_MUTE, reg6);
+}
+
+/**
+ * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
+ * alsa control.
+ * @kcontrol: mixer control
+ * @ucontrol: control element information
+ *
+ * This function basically passes the arguments on to the generic
+ * snd_soc_put_volsw() function and saves the mute information in
+ * our private data structure. This is because we want to prevent
+ * cs4270_dai_mute() neglecting the user's decision to manually
+ * mute the codec's output.
+ *
+ * Returns 0 for success.
+ */
+static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int left = !ucontrol->value.integer.value[0];
+ int right = !ucontrol->value.integer.value[1];
+
+ cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
+ (right ? CS4270_MUTE_DAC_B : 0);
+
+ return snd_soc_put_volsw(kcontrol, ucontrol);
+}
+
+/* A list of non-DAPM controls that the CS4270 supports */
+static const struct snd_kcontrol_new cs4270_snd_controls[] = {
+ SOC_DOUBLE_R("Master Playback Volume",
+ CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
+ SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
+ SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
+ SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
+ SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
+ SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
+ SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
+ SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
+ SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
+ snd_soc_get_volsw, cs4270_soc_put_mute),
+};
+
+static const struct snd_soc_dai_ops cs4270_dai_ops = {
+ .hw_params = cs4270_hw_params,
+ .set_sysclk = cs4270_set_dai_sysclk,
+ .set_fmt = cs4270_set_dai_fmt,
+ .mute_stream = cs4270_dai_mute,
+ .no_capture_mute = 1,
+};
+
+static struct snd_soc_dai_driver cs4270_dai = {
+ .name = "cs4270-hifi",
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_CONTINUOUS,
+ .rate_min = 4000,
+ .rate_max = 216000,
+ .formats = CS4270_FORMATS,
+ },
+ .capture = {
+ .stream_name = "Capture",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_CONTINUOUS,
+ .rate_min = 4000,
+ .rate_max = 216000,
+ .formats = CS4270_FORMATS,
+ },
+ .ops = &cs4270_dai_ops,
+};
+
+/**
+ * cs4270_probe - ASoC probe function
+ * @component: ASoC component
+ *
+ * This function is called when ASoC has all the pieces it needs to
+ * instantiate a sound driver.
+ */
+static int cs4270_probe(struct snd_soc_component *component)
+{
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int ret;
+
+ /* Disable auto-mute. This feature appears to be buggy. In some
+ * situations, auto-mute will not deactivate when it should, so we want
+ * this feature disabled by default. An application (e.g. alsactl) can
+ * re-enabled it by using the controls.
+ */
+ ret = snd_soc_component_update_bits(component, CS4270_MUTE, CS4270_MUTE_AUTO, 0);
+ if (ret < 0) {
+ dev_err(component->dev, "i2c write failed\n");
+ return ret;
+ }
+
+ /* Disable automatic volume control. The hardware enables, and it
+ * causes volume change commands to be delayed, sometimes until after
+ * playback has started. An application (e.g. alsactl) can
+ * re-enabled it by using the controls.
+ */
+ ret = snd_soc_component_update_bits(component, CS4270_TRANS,
+ CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0);
+ if (ret < 0) {
+ dev_err(component->dev, "i2c write failed\n");
+ return ret;
+ }
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
+ cs4270->supplies);
+
+ return ret;
+}
+
+/**
+ * cs4270_remove - ASoC remove function
+ * @component: ASoC component
+ *
+ * This function is the counterpart to cs4270_probe().
+ */
+static void cs4270_remove(struct snd_soc_component *component)
+{
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+
+ regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
+};
+
+#ifdef CONFIG_PM
+
+/* This suspend/resume implementation can handle both - a simple standby
+ * where the codec remains powered, and a full suspend, where the voltage
+ * domain the codec is connected to is teared down and/or any other hardware
+ * reset condition is asserted.
+ *
+ * The codec's own power saving features are enabled in the suspend callback,
+ * and all registers are written back to the hardware when resuming.
+ */
+
+static int cs4270_soc_suspend(struct snd_soc_component *component)
+{
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int reg, ret;
+
+ reg = snd_soc_component_read(component, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
+ if (reg < 0)
+ return reg;
+
+ ret = snd_soc_component_write(component, CS4270_PWRCTL, reg);
+ if (ret < 0)
+ return ret;
+
+ regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
+ cs4270->supplies);
+
+ return 0;
+}
+
+static int cs4270_soc_resume(struct snd_soc_component *component)
+{
+ struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
+ int reg, ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
+ cs4270->supplies);
+ if (ret != 0)
+ return ret;
+
+ /* In case the device was put to hard reset during sleep, we need to
+ * wait 500ns here before any I2C communication. */
+ ndelay(500);
+
+ /* first restore the entire register cache ... */
+ regcache_sync(cs4270->regmap);
+
+ /* ... then disable the power-down bits */
+ reg = snd_soc_component_read(component, CS4270_PWRCTL);
+ reg &= ~CS4270_PWRCTL_PDN_ALL;
+
+ return snd_soc_component_write(component, CS4270_PWRCTL, reg);
+}
+#else
+#define cs4270_soc_suspend NULL
+#define cs4270_soc_resume NULL
+#endif /* CONFIG_PM */
+
+/*
+ * ASoC codec driver structure
+ */
+static const struct snd_soc_component_driver soc_component_device_cs4270 = {
+ .probe = cs4270_probe,
+ .remove = cs4270_remove,
+ .suspend = cs4270_soc_suspend,
+ .resume = cs4270_soc_resume,
+ .controls = cs4270_snd_controls,
+ .num_controls = ARRAY_SIZE(cs4270_snd_controls),
+ .dapm_widgets = cs4270_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(cs4270_dapm_widgets),
+ .dapm_routes = cs4270_dapm_routes,
+ .num_dapm_routes = ARRAY_SIZE(cs4270_dapm_routes),
+ .idle_bias_on = 1,
+ .use_pmdown_time = 1,
+ .endianness = 1,
+};
+
+/*
+ * cs4270_of_match - the device tree bindings
+ */
+static const struct of_device_id cs4270_of_match[] = {
+ { .compatible = "cirrus,cs4270", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, cs4270_of_match);
+
+static const struct regmap_config cs4270_regmap = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = CS4270_LASTREG,
+ .reg_defaults = cs4270_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(cs4270_reg_defaults),
+ .cache_type = REGCACHE_RBTREE,
+ .write_flag_mask = CS4270_I2C_INCR,
+
+ .readable_reg = cs4270_reg_is_readable,
+ .volatile_reg = cs4270_reg_is_volatile,
+};
+
+/**
+ * cs4270_i2c_remove - deinitialize the I2C interface of the CS4270
+ * @i2c_client: the I2C client object
+ *
+ * This function puts the chip into low power mode when the i2c device
+ * is removed.
+ */
+static void cs4270_i2c_remove(struct i2c_client *i2c_client)
+{
+ struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
+
+ gpiod_set_value_cansleep(cs4270->reset_gpio, 0);
+}
+
+/**
+ * cs4270_i2c_probe - initialize the I2C interface of the CS4270
+ * @i2c_client: the I2C client object
+ *
+ * This function is called whenever the I2C subsystem finds a device that
+ * matches the device ID given via a prior call to i2c_add_driver().
+ */
+static int cs4270_i2c_probe(struct i2c_client *i2c_client)
+{
+ struct cs4270_private *cs4270;
+ unsigned int val;
+ int ret, i;
+
+ cs4270 = devm_kzalloc(&i2c_client->dev, sizeof(struct cs4270_private),
+ GFP_KERNEL);
+ if (!cs4270)
+ return -ENOMEM;
+
+ /* get the power supply regulators */
+ for (i = 0; i < ARRAY_SIZE(supply_names); i++)
+ cs4270->supplies[i].supply = supply_names[i];
+
+ ret = devm_regulator_bulk_get(&i2c_client->dev,
+ ARRAY_SIZE(cs4270->supplies),
+ cs4270->supplies);
+ if (ret < 0)
+ return ret;
+
+ /* reset the device */
+ cs4270->reset_gpio = devm_gpiod_get_optional(&i2c_client->dev, "reset",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(cs4270->reset_gpio)) {
+ dev_dbg(&i2c_client->dev, "Error getting CS4270 reset GPIO\n");
+ return PTR_ERR(cs4270->reset_gpio);
+ }
+
+ if (cs4270->reset_gpio) {
+ dev_dbg(&i2c_client->dev, "Found reset GPIO\n");
+ gpiod_set_value_cansleep(cs4270->reset_gpio, 1);
+ }
+
+ /* Sleep 500ns before i2c communications */
+ ndelay(500);
+
+ cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
+ if (IS_ERR(cs4270->regmap))
+ return PTR_ERR(cs4270->regmap);
+
+ /* Verify that we have a CS4270 */
+ ret = regmap_read(cs4270->regmap, CS4270_CHIPID, &val);
+ if (ret < 0) {
+ dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
+ i2c_client->addr);
+ return ret;
+ }
+ /* The top four bits of the chip ID should be 1100. */
+ if ((val & 0xF0) != 0xC0) {
+ dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
+ i2c_client->addr);
+ return -ENODEV;
+ }
+
+ dev_info(&i2c_client->dev, "found device at i2c address %X\n",
+ i2c_client->addr);
+ dev_info(&i2c_client->dev, "hardware revision %X\n", val & 0xF);
+
+ i2c_set_clientdata(i2c_client, cs4270);
+
+ ret = devm_snd_soc_register_component(&i2c_client->dev,
+ &soc_component_device_cs4270, &cs4270_dai, 1);
+ return ret;
+}
+
+/*
+ * cs4270_id - I2C device IDs supported by this driver
+ */
+static const struct i2c_device_id cs4270_id[] = {
+ {"cs4270", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, cs4270_id);
+
+/*
+ * cs4270_i2c_driver - I2C device identification
+ *
+ * This structure tells the I2C subsystem how to identify and support a
+ * given I2C device type.
+ */
+static struct i2c_driver cs4270_i2c_driver = {
+ .driver = {
+ .name = "cs4270",
+ .of_match_table = cs4270_of_match,
+ },
+ .id_table = cs4270_id,
+ .probe_new = cs4270_i2c_probe,
+ .remove = cs4270_i2c_remove,
+};
+
+module_i2c_driver(cs4270_i2c_driver);
+
+MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
+MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
+MODULE_LICENSE("GPL");