Merge "input: sensor: add FIR filter for noise filtering" (b7562569) · Commits · e / devices / android_kernel_sony_msm8994

Documentation/devicetree/bindings/input/misc/stk-stk3x1x.txt

+5 −0

Original line number	Diff line number	Diff line
		@@ -25,6 +25,10 @@ Required properties:
		- stk,ps-thdl : Low threshold for proximity sensor, sensor will report
		"far" if the proximity sensor reading is larger than this value.

		Optional properties:

		- stk,use-fir : Boolean to enable light data jitter suppressing FIR filter.

		Example:
		i2c@f9925000 {
		stk@48 {
		@@ -43,4 +47,5 @@ Example:
		stk,wait-reg = <0x07>;
		stk,ps-thdh = <1700>;
		stk,ps-thdl = <1500>;
		stk,use-fir;
		};

drivers/input/misc/stk3x1x.c

+147 −1

Original line number	Diff line number	Diff line
		@@ -179,6 +179,15 @@
		#define STK3X1X_VIO_MIN_UV 1750000
		#define STK3X1X_VIO_MAX_UV 1950000

		#define STK_FIR_LEN 16
		#define MAX_FIR_LEN 32
		struct data_filter {
		u16 raw[MAX_FIR_LEN];
		int sum;
		int number;
		int idx;
		};

		struct stk3x1x_data {
		struct i2c_client *client;
		#if (!defined(STK_POLL_PS) \|\| !defined(STK_POLL_ALS))
		@@ -218,6 +227,9 @@ struct stk3x1x_data {
		struct regulator *vdd;
		struct regulator *vio;
		bool power_enabled;
		bool use_fir;
		struct data_filter fir;
		atomic_t firlength;
		};

		#if( !defined(CONFIG_STK_PS_ALS_USE_CHANGE_THRESHOLD))
		@@ -387,6 +399,13 @@ static int32_t stk3x1x_init_all_reg(struct stk3x1x_data *ps_data, struct stk3x1x
		printk(KERN_ERR "%s: write i2c error\n", __func__);
		return ret;
		}

		ret = i2c_smbus_write_byte_data(ps_data->client, 0x87, 0x60);
		if (ret < 0) {
		dev_err(&ps_data->client->dev,
		"%s: write i2c error\n", __func__);
		return ret;
		}
		return 0;
		}

		@@ -708,9 +727,32 @@ static int32_t stk3x1x_enable_als(struct stk3x1x_data *ps_data, uint8_t enable)
		return ret;
		}

		static inline int32_t stk3x1x_filter_reading(struct stk3x1x_data *ps_data,
		int32_t word_data)
		{
		int index;
		int firlen = atomic_read(&ps_data->firlength);

		if (ps_data->fir.number < firlen) {
		ps_data->fir.raw[ps_data->fir.number] = word_data;
		ps_data->fir.sum += word_data;
		ps_data->fir.number++;
		ps_data->fir.idx++;
		} else {
		index = ps_data->fir.idx % firlen;
		ps_data->fir.sum -= ps_data->fir.raw[index];
		ps_data->fir.raw[index] = word_data;
		ps_data->fir.sum += word_data;
		ps_data->fir.idx++;
		word_data = ps_data->fir.sum/firlen;
		}
		return word_data;
		}

		static inline int32_t stk3x1x_get_als_reading(struct stk3x1x_data *ps_data)
		{
		int32_t word_data, tmp_word_data;

		tmp_word_data = i2c_smbus_read_word_data(ps_data->client, STK_DATA1_ALS_REG);
		if(tmp_word_data < 0)
		{
		@@ -718,6 +760,9 @@ static inline int32_t stk3x1x_get_als_reading(struct stk3x1x_data *ps_data)
		return tmp_word_data;
		}
		word_data = ((tmp_word_data & 0xFF00) >> 8) \| ((tmp_word_data & 0x00FF) << 8) ;
		if (ps_data->use_fir)
		word_data = stk3x1x_filter_reading(ps_data, word_data);

		return word_data;
		}

		@@ -912,7 +957,12 @@ static ssize_t stk_als_delay_show(struct device dev, struct device_attribute a
		return scnprintf(buf, PAGE_SIZE, "%lld\n", ktime_to_ns(ps_data->als_poll_delay));
		}


		static inline void stk_als_delay_store_fir(struct stk3x1x_data *ps_data)
		{
		ps_data->fir.number = 0;
		ps_data->fir.idx = 0;
		ps_data->fir.sum = 0;
		}
		static ssize_t stk_als_delay_store(struct device dev, struct device_attribute attr, const char *buf, size_t size)
		{
		uint64_t value = 0;
		@@ -936,6 +986,10 @@ static ssize_t stk_als_delay_store(struct device dev, struct device_attribute
		mutex_lock(&ps_data->io_lock);
		if(value != ktime_to_ns(ps_data->als_poll_delay))
		ps_data->als_poll_delay = ns_to_ktime(value);

		if (ps_data->use_fir)
		stk_als_delay_store_fir(ps_data);

		mutex_unlock(&ps_data->io_lock);
		return size;
		}
		@@ -948,6 +1002,77 @@ static ssize_t stk_als_ir_code_show(struct device *dev, struct device_attribute
		return scnprintf(buf, PAGE_SIZE, "%d\n", reading);
		}

		static ssize_t stk_als_firlen_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct stk3x1x_data *ps_data = dev_get_drvdata(dev);
		int len = atomic_read(&ps_data->firlength);

		dev_dbg(dev, "%s: len = %2d, idx = %2d\n",
		__func__, len, ps_data->fir.idx);
		dev_dbg(dev, "%s: sum = %5d, ave = %5d\n",
		__func__, ps_data->fir.sum, ps_data->fir.sum/len);

		return scnprintf(buf, PAGE_SIZE, "%d\n", len);
		}

		static ssize_t stk_als_firlen_store(struct device *dev,
		struct device_attribute *attr,
		const char *buf, size_t size)
		{
		uint64_t value = 0;
		int ret;
		struct stk3x1x_data *ps_data = dev_get_drvdata(dev);
		ret = kstrtoull(buf, 10, &value);
		if (ret < 0) {
		dev_err(dev, "%s:strict_strtoull failed, ret=0x%x\n",
		__func__, ret);
		return ret;
		}

		if (value > MAX_FIR_LEN) {
		dev_err(dev, "%s: firlen exceed maximum filter length\n",
		__func__);
		} else if (value < 1) {
		atomic_set(&ps_data->firlength, 1);
		memset(&ps_data->fir, 0x00, sizeof(ps_data->fir));
		} else {
		atomic_set(&ps_data->firlength, value);
		memset(&ps_data->fir, 0x00, sizeof(ps_data->fir));
		}
		return size;
		}

		static ssize_t stk_als_fir_enable_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct stk3x1x_data *ps_data = dev_get_drvdata(dev);

		return scnprintf(buf, PAGE_SIZE, "%d\n", ps_data->use_fir);
		}

		static ssize_t stk_als_fir_enable_store(struct device *dev,
		struct device_attribute *attr,
		const char *buf, size_t size)
		{
		uint64_t value = 0;
		int ret;
		struct stk3x1x_data *ps_data = dev_get_drvdata(dev);
		ret = kstrtoull(buf, 10, &value);
		if (ret < 0) {
		dev_err(dev, "%s:strict_strtoull failed, ret=0x%x\n",
		__func__, ret);
		return ret;
		}

		if (value) {
		ps_data->use_fir = true;
		memset(&ps_data->fir, 0x00, sizeof(ps_data->fir));
		} else {
		ps_data->use_fir = false;
		}
		return size;
		}
		static ssize_t stk_ps_code_show(struct device dev, struct device_attribute attr, char *buf)
		{
		struct stk3x1x_data *ps_data = dev_get_drvdata(dev);
		@@ -1432,6 +1557,11 @@ static struct device_attribute als_transmittance_attribute = __ATTR(transmittanc
		static struct device_attribute als_poll_delay_attribute =
		__ATTR(poll_delay, 0664, stk_als_delay_show, stk_als_delay_store);
		static struct device_attribute als_ir_code_attribute = __ATTR(ircode,0444,stk_als_ir_code_show,NULL);
		static struct device_attribute als_firlen_attribute =
		__ATTR(firlen, 0664, stk_als_firlen_show, stk_als_firlen_store);
		static struct device_attribute als_fir_enable_attribute =
		__ATTR(fir_enable, 0664, stk_als_fir_enable_show,
		stk_als_fir_enable_store);

		static struct attribute *stk_als_attrs [] =
		{
		@@ -1441,6 +1571,8 @@ static struct attribute *stk_als_attrs [] =
		&als_transmittance_attribute.attr,
		&als_poll_delay_attribute.attr,
		&als_ir_code_attribute.attr,
		&als_firlen_attribute.attr,
		&als_fir_enable_attribute.attr,
		NULL
		};

		@@ -1673,6 +1805,13 @@ static irqreturn_t stk_oss_irq_handler(int irq, void *data)
		return IRQ_HANDLED;
		}
		#endif /* #if (!defined(STK_POLL_PS) \|\| !defined(STK_POLL_ALS)) */

		static inline void stk3x1x_init_fir(struct stk3x1x_data *ps_data)
		{
		memset(&ps_data->fir, 0x00, sizeof(ps_data->fir));
		atomic_set(&ps_data->firlength, STK_FIR_LEN);
		}

		static int32_t stk3x1x_init_all_setting(struct i2c_client client, struct stk3x1x_platform_data plat_data)
		{
		int32_t ret;
		@@ -1697,6 +1836,10 @@ static int32_t stk3x1x_init_all_setting(struct i2c_client *client, struct stk3x1
		#ifndef CONFIG_STK_PS_ALS_USE_CHANGE_THRESHOLD
		stk_init_code_threshold_table(ps_data);
		#endif

		if (plat_data->use_fir)
		stk3x1x_init_fir(ps_data);

		return 0;
		}

		@@ -1998,6 +2141,8 @@ static int stk3x1x_parse_dt(struct device *dev,
		return rc;
		}

		pdata->use_fir = of_property_read_bool(np, "stk,use-fir");

		return 0;
		}
		#else
		@@ -2064,6 +2209,7 @@ static int stk3x1x_probe(struct i2c_client *client,
		}
		ps_data->als_transmittance = plat_data->transmittance;
		ps_data->int_pin = plat_data->int_pin;
		ps_data->use_fir = plat_data->use_fir;

		if (ps_data->als_transmittance == 0) {
		dev_err(&client->dev,

include/linux/stk3x1x.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@ struct stk3x1x_platform_data {
		int int_pin;
		uint32_t transmittance;
		uint32_t int_flags;
		bool use_fir;
		};

		#endif /* __STK3X1X_H__ */