/* * CS4270 ALSA SoC (ASoC) codec driver * * Author: Timur Tabi * * 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 #include #include #include #include #include #include #include #include /* * The codec isn't really big-endian or little-endian, since the I2S * interface requires data to be sent serially with the MSbit first. * However, to support BE and LE I2S devices, we specify both here. That * way, ALSA will always match the bit patterns. */ #define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8 | \ SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_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) /* 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. * * Also note that on the CS4270, the first readable register is 1, but ASoC * assumes the first register is 0. Therfore, the array must have an entry for * register 0, but we use cs4270_reg_is_readable() to tell ASoC that it can't * be read. */ static const u8 cs4270_default_reg_cache[CS4270_LASTREG + 1] = { 0x00, 0x00, 0x00, 0x30, 0x00, 0x60, 0x20, 0x00, 0x00 }; static const char *supply_names[] = { "va", "vd", "vlc" }; /* Private data for the CS4270 */ struct cs4270_private { enum snd_soc_control_type control_type; void *control_data; 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)]; }; /** * 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 int cs4270_reg_is_readable(struct snd_soc_codec *codec, unsigned int reg) { return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG); } static int cs4270_reg_is_volatile(struct snd_soc_codec *codec, unsigned int reg) { /* Unreadable registers are considered volatile */ if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG)) return 1; 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_codec *codec = codec_dai->codec; struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); 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_codec *codec = codec_dai->codec; struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); int ret = 0; /* 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(codec->dev, "invalid dai format\n"); ret = -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 */ ret = -EINVAL; } return ret; } /** * 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_pcm_runtime *rtd = substream->private_data; struct snd_soc_codec *codec = rtd->codec; struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); 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(codec->dev, "could not find matching ratio\n"); return -EINVAL; } /* Set the sample rate */ reg = snd_soc_read(codec, 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_write(codec, CS4270_MODE, reg); if (ret < 0) { dev_err(codec->dev, "i2c write failed\n"); return ret; } /* Set the DAI format */ reg = snd_soc_read(codec, 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(codec->dev, "unknown dai format\n"); return -EINVAL; } ret = snd_soc_write(codec, CS4270_FORMAT, reg); if (ret < 0) { dev_err(codec->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 * * 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) { struct snd_soc_codec *codec = dai->codec; struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); int reg6; reg6 = snd_soc_read(codec, 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_write(codec, 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_codec *codec = snd_kcontrol_chip(kcontrol); struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); 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 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, .digital_mute = cs4270_dai_mute, }; static struct snd_soc_dai_driver cs4270_dai = { .name = "cs4270-hifi", .playback = { .stream_name = "Playback", .channels_min = 1, .channels_max = 2, .rates = SNDRV_PCM_RATE_CONTINUOUS, .rate_min = 4000, .rate_max = 216000, .formats = CS4270_FORMATS, }, .capture = { .stream_name = "Capture", .channels_min = 1, .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 * @pdev: platform device * * This function is called when ASoC has all the pieces it needs to * instantiate a sound driver. */ static int cs4270_probe(struct snd_soc_codec *codec) { struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); int i, ret; codec->control_data = cs4270->control_data; /* Tell ASoC what kind of I/O to use to read the registers. ASoC will * then do the I2C transactions itself. */ ret = snd_soc_codec_set_cache_io(codec, 8, 8, cs4270->control_type); if (ret < 0) { dev_err(codec->dev, "failed to set cache I/O (ret=%i)\n", ret); return 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_update_bits(codec, CS4270_MUTE, CS4270_MUTE_AUTO, 0); if (ret < 0) { dev_err(codec->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_update_bits(codec, CS4270_TRANS, CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0); if (ret < 0) { dev_err(codec->dev, "i2c write failed\n"); return ret; } /* Add the non-DAPM controls */ ret = snd_soc_add_controls(codec, cs4270_snd_controls, ARRAY_SIZE(cs4270_snd_controls)); if (ret < 0) { dev_err(codec->dev, "failed to add controls\n"); return ret; } /* get the power supply regulators */ for (i = 0; i < ARRAY_SIZE(supply_names); i++) cs4270->supplies[i].supply = supply_names[i]; ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(cs4270->supplies), cs4270->supplies); if (ret < 0) return ret; ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies); if (ret < 0) goto error_free_regulators; return 0; error_free_regulators: regulator_bulk_free(ARRAY_SIZE(cs4270->supplies), cs4270->supplies); return ret; } /** * cs4270_remove - ASoC remove function * @pdev: platform device * * This function is the counterpart to cs4270_probe(). */ static int cs4270_remove(struct snd_soc_codec *codec) { struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies); regulator_bulk_free(ARRAY_SIZE(cs4270->supplies), cs4270->supplies); return 0; }; #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_codec *codec, pm_message_t mesg) { struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); int reg, ret; reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL; if (reg < 0) return reg; ret = snd_soc_write(codec, 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_codec *codec) { struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec); struct i2c_client *i2c_client = codec->control_data; int reg; regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies); /* 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 ... */ for (reg = CS4270_FIRSTREG; reg <= CS4270_LASTREG; reg++) { u8 val = snd_soc_read(codec, reg); if (i2c_smbus_write_byte_data(i2c_client, reg, val)) { dev_err(codec->dev, "i2c write failed\n"); return -EIO; } } /* ... then disable the power-down bits */ reg = snd_soc_read(codec, CS4270_PWRCTL); reg &= ~CS4270_PWRCTL_PDN_ALL; return snd_soc_write(codec, 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_codec_driver soc_codec_device_cs4270 = { .probe = cs4270_probe, .remove = cs4270_remove, .suspend = cs4270_soc_suspend, .resume = cs4270_soc_resume, .volatile_register = cs4270_reg_is_volatile, .readable_register = cs4270_reg_is_readable, .reg_cache_size = CS4270_LASTREG + 1, .reg_word_size = sizeof(u8), .reg_cache_default = cs4270_default_reg_cache, }; /** * cs4270_i2c_probe - initialize the I2C interface of the CS4270 * @i2c_client: the I2C client object * @id: the I2C device ID (ignored) * * 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, const struct i2c_device_id *id) { struct cs4270_private *cs4270; int ret; /* Verify that we have a CS4270 */ ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID); 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 ((ret & 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", ret & 0xF); cs4270 = kzalloc(sizeof(struct cs4270_private), GFP_KERNEL); if (!cs4270) { dev_err(&i2c_client->dev, "could not allocate codec\n"); return -ENOMEM; } i2c_set_clientdata(i2c_client, cs4270); cs4270->control_data = i2c_client; cs4270->control_type = SND_SOC_I2C; ret = snd_soc_register_codec(&i2c_client->dev, &soc_codec_device_cs4270, &cs4270_dai, 1); if (ret < 0) kfree(cs4270); return ret; } /** * cs4270_i2c_remove - remove an I2C device * @i2c_client: the I2C client object * * This function is the counterpart to cs4270_i2c_probe(). */ static int cs4270_i2c_remove(struct i2c_client *i2c_client) { snd_soc_unregister_codec(&i2c_client->dev); kfree(i2c_get_clientdata(i2c_client)); return 0; } /* * 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-codec", .owner = THIS_MODULE, }, .id_table = cs4270_id, .probe = cs4270_i2c_probe, .remove = cs4270_i2c_remove, }; static int __init cs4270_init(void) { return i2c_add_driver(&cs4270_i2c_driver); } module_init(cs4270_init); static void __exit cs4270_exit(void) { i2c_del_driver(&cs4270_i2c_driver); } module_exit(cs4270_exit); MODULE_AUTHOR("Timur Tabi "); MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver"); MODULE_LICENSE("GPL");