Some Samsung devices that use the midas_wm1811 driver use a GPIO-based method for detecting whether the headset jack is plugged in, as well as detecting which headset buttons are pressed. There are two GPIOs: a "headset detect" GPIO responsible for detecting jack insertion, and a "headset key" GPIO which triggers when a button on the headset is pressed. The plug type and the button pressed are determined based on information from an ADC channel. The headset mic is enabled by a headset mic bias regulator.
Add support for the GPIO-based headset jack detection mechanism, and make it configurable from the device tree.
This implementation borrows somewhat from the aries_wm8994.c driver, though there are a few changes to make the code cleaner, and to add support for DT-based configuration.
Notably, a dependency on IIO is introduced, to accommodate the ADC reading requirement.
Signed-off-by: Artur Weber aweber.kernel@gmail.com --- Changes in v2: - Added separate headset mic bias regulator - Added samsung preset to threshold properties - Replaced dev_err+return with return dev_err_probe where needed --- sound/soc/samsung/Kconfig | 2 +- sound/soc/samsung/midas_wm1811.c | 286 +++++++++++++++++++++++++++++++++++++-- 2 files changed, 277 insertions(+), 11 deletions(-)
diff --git a/sound/soc/samsung/Kconfig b/sound/soc/samsung/Kconfig index 93c2b1b08d0a..4b1ea7b2c796 100644 --- a/sound/soc/samsung/Kconfig +++ b/sound/soc/samsung/Kconfig @@ -140,7 +140,7 @@ config SND_SOC_SAMSUNG_ARIES_WM8994
config SND_SOC_SAMSUNG_MIDAS_WM1811 tristate "SoC I2S Audio support for Midas boards" - depends on SND_SOC_SAMSUNG + depends on SND_SOC_SAMSUNG && IIO select SND_SAMSUNG_I2S select SND_SOC_WM8994 help diff --git a/sound/soc/samsung/midas_wm1811.c b/sound/soc/samsung/midas_wm1811.c index ab0a4804b45e..ce94550ee32e 100644 --- a/sound/soc/samsung/midas_wm1811.c +++ b/sound/soc/samsung/midas_wm1811.c @@ -7,7 +7,9 @@
#include <linux/clk.h> #include <linux/gpio/consumer.h> +#include <linux/iio/consumer.h> #include <linux/mfd/wm8994/registers.h> +#include <linux/input-event-codes.h> #include <linux/module.h> #include <linux/of.h> #include <linux/regulator/consumer.h> @@ -32,6 +34,9 @@ struct midas_priv { struct regulator *reg_headset_mic_bias; struct gpio_desc *gpio_fm_sel; struct gpio_desc *gpio_lineout_sel; + struct gpio_desc *gpio_headset_detect; + struct gpio_desc *gpio_headset_key; + struct iio_channel *adc_headset_detect; unsigned int fll1_rate;
struct snd_soc_jack headset_jack; @@ -48,6 +53,131 @@ static struct snd_soc_jack_pin headset_jack_pins[] = { }, };
+/* + * min_mv/max_mv values in this struct are set up based on DT values. + */ +static struct snd_soc_jack_zone headset_jack_zones[] = { + { .jack_type = SND_JACK_HEADPHONE, }, + { .jack_type = SND_JACK_HEADSET, }, + { .jack_type = SND_JACK_HEADPHONE, }, +}; + +/* + * This is used for manual detection in headset_key_check, we reuse the + * structure since it's convenient. + * + * min_mv/max_mv values in this struct are set up based on DT values. + */ +static struct snd_soc_jack_zone headset_key_zones[] = { + { .jack_type = SND_JACK_BTN_0, }, /* Media */ + { .jack_type = SND_JACK_BTN_1, }, /* Volume Up */ + { .jack_type = SND_JACK_BTN_2, }, /* Volume Down */ +}; + +static int headset_jack_check(void *data) +{ + struct midas_priv *priv = (struct midas_priv *) data; + int adc, jack_type, ret; + int bias_already_on = 0; + + if (!gpiod_get_value_cansleep(priv->gpio_headset_detect)) + return 0; + + if (priv->reg_headset_mic_bias) { + /* + * Get state of Headset Mic switch by checking the headset mic + * bias regulator + */ + bias_already_on = \ + regulator_is_enabled(priv->reg_headset_mic_bias); + + /* + * If it's not enabled yet, temporarily enable headset mic bias + * for ADC measurement + */ + if (bias_already_on < 0) + pr_err("%s: Failed to get headset mic bias state: %d", + __func__, ret); + else if (!bias_already_on) { + ret = regulator_enable(priv->reg_headset_mic_bias); + if (ret) + pr_err("%s: Failed to enable micbias: %d\n", + __func__, ret); + } + } + + /* Sleep for a small amount of time to get the value to stabilize */ + msleep(20); + + ret = iio_read_channel_processed(priv->adc_headset_detect, &adc); + if (ret) { + pr_err("%s: Failed to read ADC (%d), assuming headphones\n", + __func__, ret); + return SND_JACK_HEADPHONE; + } + pr_debug("%s: ADC value is %d\n", __func__, adc); + + jack_type = snd_soc_jack_get_type(&priv->headset_jack, adc); + + /* + * Revert the headset mic bias supply to its previous state + * (i.e. if it was disabled before the check, disable it again) + */ + if (priv->reg_headset_mic_bias && bias_already_on == 0) { + ret = regulator_disable(priv->reg_headset_mic_bias); + if (ret) + pr_err("%s: Failed to disable micbias: %d\n", + __func__, ret); + } + + return jack_type; +} + +static int headset_key_check(void *data) +{ + struct midas_priv *priv = (struct midas_priv *) data; + int adc, i, ret; + + if (!gpiod_get_value_cansleep(priv->gpio_headset_key)) + return 0; + + /* Filter out keypresses when 4 pole jack not detected */ + if (!(priv->headset_jack.status & SND_JACK_MICROPHONE)) + return 0; + + ret = iio_read_channel_processed(priv->adc_headset_detect, &adc); + if (ret) { + pr_err("%s: Failed to read ADC (%d), can't detect key type\n", + __func__, ret); + return 0; + } + pr_debug("%s: ADC value is %d\n", __func__, adc); + + for (i = 0; i < ARRAY_SIZE(headset_key_zones); i++) { + if (adc >= headset_key_zones[i].min_mv && + adc <= headset_key_zones[i].max_mv) { + return headset_key_zones[i].jack_type; + } + } + + return 0; +} + +static struct snd_soc_jack_gpio headset_gpio[] = { + { + .name = "Headset Jack", + .report = SND_JACK_HEADSET, + .debounce_time = 150, + .jack_status_check = headset_jack_check, + }, + { + .name = "Headset Key", + .report = SND_JACK_BTN_0 | SND_JACK_BTN_1 | SND_JACK_BTN_2, + .debounce_time = 30, + .jack_status_check = headset_key_check, + }, +}; + static int midas_start_fll1(struct snd_soc_pcm_runtime *rtd, unsigned int rate) { struct snd_soc_card *card = rtd->card; @@ -335,18 +465,67 @@ static int midas_late_probe(struct snd_soc_card *card) return ret; }
- ret = snd_soc_card_jack_new_pins(card, "Headset", - SND_JACK_HEADSET | SND_JACK_MECHANICAL | - SND_JACK_BTN_0 | SND_JACK_BTN_1 | SND_JACK_BTN_2 | - SND_JACK_BTN_3 | SND_JACK_BTN_4 | SND_JACK_BTN_5, - &priv->headset_jack, - headset_jack_pins, - ARRAY_SIZE(headset_jack_pins)); - if (ret) + if (!priv->gpio_headset_detect) { + ret = snd_soc_card_jack_new_pins(card, "Headset", + SND_JACK_HEADSET | SND_JACK_MECHANICAL | + SND_JACK_BTN_0 | SND_JACK_BTN_1 | + SND_JACK_BTN_2 | SND_JACK_BTN_3 | + SND_JACK_BTN_4 | SND_JACK_BTN_5, + &priv->headset_jack, + headset_jack_pins, + ARRAY_SIZE(headset_jack_pins)); + if (ret) + return ret; + + wm8958_mic_detect(aif1_dai->component, &priv->headset_jack, + NULL, NULL, NULL, NULL); + } else { + /* Some devices (n8000, t310) use a GPIO to detect the jack. */ + ret = snd_soc_card_jack_new_pins(card, "Headset", + SND_JACK_HEADSET | SND_JACK_BTN_0 | + SND_JACK_BTN_1 | SND_JACK_BTN_2, + &priv->headset_jack, + headset_jack_pins, + ARRAY_SIZE(headset_jack_pins)); + if (ret) { + dev_err(card->dev, + "Failed to set up headset pins: %d\n", ret); + return ret; + } + + ret = snd_soc_jack_add_zones(&priv->headset_jack, + ARRAY_SIZE(headset_jack_zones), + headset_jack_zones); + if (ret) { + dev_err(card->dev, + "Failed to set up headset zones: %d\n", ret); + return ret; + } + + headset_gpio[0].data = priv; + headset_gpio[0].desc = priv->gpio_headset_detect; + + headset_gpio[1].data = priv; + headset_gpio[1].desc = priv->gpio_headset_key; + + snd_jack_set_key(priv->headset_jack.jack, + SND_JACK_BTN_0, KEY_MEDIA); + snd_jack_set_key(priv->headset_jack.jack, + SND_JACK_BTN_1, KEY_VOLUMEUP); + snd_jack_set_key(priv->headset_jack.jack, + SND_JACK_BTN_2, KEY_VOLUMEDOWN); + + ret = snd_soc_jack_add_gpios(&priv->headset_jack, + ARRAY_SIZE(headset_gpio), + headset_gpio); + if (ret) + dev_err(card->dev, + "Failed to set up headset jack GPIOs: %d\n", + ret); + return ret; + }
- wm8958_mic_detect(aif1_dai->component, &priv->headset_jack, - NULL, NULL, NULL, NULL); return 0; }
@@ -453,6 +632,9 @@ static int midas_probe(struct platform_device *pdev) struct snd_soc_card *card = &midas_card; struct device *dev = &pdev->dev; static struct snd_soc_dai_link *dai_link; + enum iio_chan_type channel_type; + u32 fourpole_threshold[2]; + u32 button_threshold[3]; struct midas_priv *priv; int ret, i;
@@ -499,6 +681,90 @@ static int midas_probe(struct platform_device *pdev) return PTR_ERR(priv->gpio_lineout_sel); }
+ priv->gpio_headset_detect = devm_gpiod_get_optional(dev, + "headset-detect", GPIOD_IN); + if (IS_ERR(priv->gpio_headset_detect)) + return dev_err_probe(dev, PTR_ERR(priv->gpio_headset_detect), + "Failed to get headset jack detect GPIO\n"); + + if (priv->gpio_headset_detect) { + priv->adc_headset_detect = devm_iio_channel_get(dev, + "headset-detect"); + if (IS_ERR(priv->adc_headset_detect)) + return dev_err_probe(dev, + PTR_ERR(priv->adc_headset_detect), + "Failed to get ADC channel\n"); + + ret = iio_get_channel_type(priv->adc_headset_detect, + &channel_type); + if (ret) { + dev_err(dev, "Failed to get ADC channel type\n"); + return ret; + } + + if (channel_type != IIO_VOLTAGE) { + dev_err(dev, "ADC channel is not voltage\n"); + return ret; + } + + priv->gpio_headset_key = devm_gpiod_get(dev, "headset-key", + GPIOD_IN); + if (IS_ERR(priv->gpio_headset_key)) + return dev_err_probe(dev, + PTR_ERR(priv->gpio_headset_key), + "Failed to get headset key GPIO\n"); + + ret = of_property_read_u32_array(dev->of_node, + "samsung,headset-4pole-threshold-microvolt", + fourpole_threshold, + ARRAY_SIZE(fourpole_threshold)); + if (ret) { + dev_err(dev, "Failed to get 4-pole jack detection threshold\n"); + return ret; + } + + if (fourpole_threshold[0] > fourpole_threshold[1]) { + dev_err(dev, "Invalid 4-pole jack detection threshold value\n"); + return -EINVAL; + } + + headset_jack_zones[0].max_mv = (fourpole_threshold[0]); + headset_jack_zones[1].min_mv = (fourpole_threshold[0] + 1); + + headset_jack_zones[1].max_mv = (fourpole_threshold[1]); + headset_jack_zones[2].min_mv = (fourpole_threshold[1] + 1); + + ret = of_property_read_u32_array(dev->of_node, + "samsung,headset-button-threshold-microvolt", + button_threshold, + ARRAY_SIZE(button_threshold)); + if (ret) { + dev_err(dev, "Failed to get headset button detection threshold\n"); + return ret; + } + + if (button_threshold[0] > button_threshold[1] || + button_threshold[1] > button_threshold[2]) { + dev_err(dev, "Invalid headset button detection threshold value\n"); + return -EINVAL; + } + + for (i = 0; i < 3; i++) { + if (i != 0 && button_threshold[i] <= 0) { + dev_err(dev, "Invalid headset button detection threshold value\n"); + return -EINVAL; + } + + headset_key_zones[i].min_mv = button_threshold[i]; + + if (i == 2) + headset_key_zones[i].max_mv = UINT_MAX; + else + headset_key_zones[i].max_mv = \ + (button_threshold[i+1] - 1); + } + } + ret = snd_soc_of_parse_card_name(card, "model"); if (ret < 0) { dev_err(dev, "Card name is not specified\n");