Merge "input: sensors: add LTR553 auto gain switch feature" (5170e4d3) · Commits · e / devices / samsung / android_kernel_samsung_msm8916

Documentation/devicetree/bindings/input/misc/ltr553.txt

+4 −0

Original line number	Diff line number	Diff line
		@@ -39,6 +39,9 @@ Required properties:
		light ratio above 0.99.
		- liteon,wakeup-threshold : Threshold in centimeter to wake up SoC in
		suspend mode when proximity is enabled.
		- liteon,als-sensitivity : Ambient light sensitivity in lux. This array
		configures how much light intensity change will trigger a light sensor
		event under different als gain configuration. The array size must be 8.

		Example:

		@@ -59,5 +62,6 @@ Required properties:
		liteon,ps-pulses = <4>;
		liteon,wakeup-threshold = <4>;
		liteon,als-integration-time = <0>;
		liteon,als-sensitivity = <6000 3200 1600 800 0 0 130 1>;
		};
		}

drivers/input/misc/ltr553.c

+173 −54

Original line number	Diff line number	Diff line
		@@ -79,6 +79,10 @@

		#define LTR553_CALIBRATE_SAMPLES 15

		#define ALS_GAIN_SWITCH_THRESHOLD 60000

		#define LTR553_ALS_INVALID(value) (value & 0x80)

		/* LTR553 ALS data is 16 bit */
		#define ALS_DATA_MASK 0xffff
		#define ALS_LOW_BYTE(data) ((data) & 0xff)
		@@ -150,7 +154,6 @@ struct ltr553_data {
		int als_persist;
		int als_integration_time;
		int als_measure_rate;
		int als_sensitivity;
		int ps_led;
		int ps_pulses;
		int ps_measure_rate;
		@@ -233,6 +236,8 @@ static int ps_mrr_table[] = { 50, 70, 100, 200, 500, 1000, 2000, 10,
		/* Tuned for devices with rubber */
		static int ps_distance_table[] = { 790, 337, 195, 114, 78, 62, 50 };

		static int sensitivity_table[] = {150, 150, 100, 100, 0, 0, 100, 1};

		static struct sensors_classdev als_cdev = {
		.name = "ltr553-light",
		.vendor = "Lite-On Technology Corp",
		@@ -487,18 +492,16 @@ static int ltr553_parse_dt(struct device dev, struct ltr553_data ltr)
		}
		/* 4 & 5 are reserved */
		if ((value > 0x7) \|\| (value == 0x4) \|\| (value == 0x5)) {
		dev_err(dev, "liteon,als-integration-time out of range\n");
		dev_err(dev, "liteon,als-gain invalid\n");
		return -EINVAL;
		}
		ltr->als_gain = value;

		/* als sensitivity */
		rc = of_property_read_u32(dp, "liteon,als-sensitivity", &value);
		if (rc) {
		dev_err(dev, "read liteon,als-sensitivity failed. Drop to default\n");
		value = LTR553_ALS_SENSITIVITY;
		}
		ltr->als_sensitivity = value;
		rc = of_property_read_u32_array(dp, "liteon,als-sensitivity",
		sensitivity_table, ARRAY_SIZE(sensitivity_table));
		if (rc)
		dev_info(dev, "read liteon,als-sensitivity failed. Drop to default\n");

		/* als equation map */
		rc = of_property_read_u32_array(dp, "liteon,als-equation-0",
		@@ -596,6 +599,7 @@ static int ltr553_init_input(struct ltr553_data *ltr)
		static int ltr553_init_device(struct ltr553_data *ltr)
		{
		int rc;
		unsigned int tmp;

		/* Enable als/ps interrupt */
		rc = regmap_write(ltr->regmap, LTR553_REG_INTERRUPT,
		@@ -655,6 +659,21 @@ static int ltr553_init_device(struct ltr553_data *ltr)
		return rc;
		}

		/* set up als gain */
		rc = regmap_read(ltr->regmap, LTR553_REG_ALS_CTL, &tmp);
		if (rc) {
		dev_err(&ltr->i2c->dev, "read %d register failed\n",
		LTR553_REG_ALS_CTL);
		return rc;
		}
		rc = regmap_write(ltr->regmap, LTR553_REG_ALS_CTL,
		(tmp & (~0x1c)) \| (ltr->als_gain << 2));
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d register failed\n",
		LTR553_REG_ALS_CTL);
		return rc;
		}

		return 0;
		}

		@@ -675,9 +694,9 @@ static int ltr553_calc_lux(int ch0data, int ch1data, int gain,
		ratio = ch1data * 100 / (ch0data + ch1data);
		if (ratio < 45)
		eqtn = &eqtn_map[0];
		else if ((ratio >= 45) && (ratio < 68))
		else if ((ratio >= 45) && (ratio < 74))
		eqtn = &eqtn_map[1];
		else if ((ratio >= 68) && (ratio < 99))
		else if ((ratio >= 74) && (ratio < 99))
		eqtn = &eqtn_map[2];
		else
		eqtn = &eqtn_map[3];
		@@ -730,6 +749,123 @@ static int ltr553_calc_adc(int ratio, int lux, int gain,
		return result <= 0 ? 1 : result;
		}

		/* update als gain and threshold */
		static int ltr553_als_update_setting(struct ltr553_data *ltr,
		unsigned int ch0data, unsigned int ch1data,
		unsigned int als_int_fac)
		{
		int gain_index;
		unsigned int config;
		unsigned int ratio;
		unsigned int adc_base;
		int rc;
		int adc;
		int i;
		u8 als_data[4];

		for (i = ARRAY_SIZE(als_gain_table) - 1; i >= 0; i--) {
		if ((i == 4) \|\| (i == 5))
		continue;

		if ((ch0data + ch1data) * als_gain_table[i] /
		als_gain_table[ltr->als_gain] <
		ALS_GAIN_SWITCH_THRESHOLD)
		break;
		}

		gain_index = i < 0 ? 0 : i;

		/*
		* Disable als and enable it again to avoid incorrect value.
		* Updating als gain during als measurement cycle will cause
		* incorrect light sensor adc value. The logic here is to handle
		* this scenario.
		*/

		if (ltr->als_gain != gain_index) {
		rc = regmap_read(ltr->regmap, LTR553_REG_ALS_CTL, &config);
		if (rc) {
		dev_err(&ltr->i2c->dev, "read %d failed.(%d)\n",
		LTR553_REG_ALS_CTL, rc);
		return rc;
		}

		/* disable als sensor */
		rc = regmap_write(ltr->regmap, LTR553_REG_ALS_CTL,
		config & (~0x1));
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_ALS_CTL, rc);
		return rc;
		}

		/* write new als gain */
		rc = regmap_write(ltr->regmap, LTR553_REG_ALS_CTL,
		(config & (~0x1c)) \| (gain_index << 2));
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d register failed\n",
		LTR553_REG_ALS_CTL);
		return rc;
		}
		}

		if ((ch0data == 0) && (ch1data == 0)) {
		adc = 1;
		} else {
		ratio = ch1data * 100 / (ch0data + ch1data);
		dev_dbg(&ltr->i2c->dev, "ratio:%d\n", ratio);
		adc = ltr553_calc_adc(ratio, sensitivity_table[gain_index],
		als_gain_table[gain_index], als_int_fac);
		}

		dev_dbg(&ltr->i2c->dev, "adc:%d\n", adc);

		/* catch'ya! */
		adc_base = ch0data * als_gain_table[gain_index] /
		als_gain_table[ltr->als_gain];

		/* upper threshold */
		if (adc_base + adc > ALS_DATA_MASK) {
		als_data[0] = 0xff;
		als_data[1] = 0xff;
		} else {
		als_data[0] = ALS_LOW_BYTE(adc_base + adc);
		als_data[1] = ALS_HIGH_BYTE(adc_base + adc);
		}

		/* lower threshold */
		if (adc_base < adc) {
		als_data[2] = 0x0;
		als_data[3] = 0x0;
		} else {
		als_data[2] = ALS_LOW_BYTE(adc_base - adc);
		als_data[3] = ALS_HIGH_BYTE(adc_base - adc);
		}

		rc = regmap_bulk_write(ltr->regmap, LTR553_REG_ALS_THRES_UP_0,
		als_data, 4);
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_ALS_THRES_UP_0, rc);
		return rc;
		}

		if (ltr->als_gain != gain_index) {
		/* enable als_sensor */
		rc = regmap_write(ltr->regmap, LTR553_REG_ALS_CTL,
		(config & (~0x1c)) \| (gain_index << 2) \| 0x1);
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_ALS_CTL, rc);
		return rc;
		}

		ltr->als_gain = gain_index;
		}

		return 0;
		}

		static int ltr553_process_data(struct ltr553_data *ltr, int als_ps)
		{
		unsigned int als_int_fac;
		@@ -741,8 +877,6 @@ static int ltr553_process_data(struct ltr553_data *ltr, int als_ps)
		int lux;
		unsigned int ch0data;
		unsigned int ch1data;
		int adc;
		int ratio;

		u8 ps_data[4];
		int i;
		@@ -778,7 +912,15 @@ static int ltr553_process_data(struct ltr553_data *ltr, int als_ps)
		lux, als_data[0], als_data[1],
		als_data[2], als_data[3]);

		if (lux != ltr->last_als) {
		rc = regmap_read(ltr->regmap, LTR553_REG_ALS_PS_STATUS, &tmp);
		if (rc) {
		dev_err(&ltr->i2c->dev, "read %d failed.(%d)\n",
		LTR553_REG_ALS_PS_STATUS, rc);
		goto exit;
		}


		if ((lux != ltr->last_als) && (!LTR553_ALS_INVALID(tmp))) {
		input_report_abs(ltr->input_light, ABS_MISC, lux);
		input_event(ltr->input_light, EV_SYN, SYN_TIME_SEC,
		ktime_to_timespec(timestamp).tv_sec);
		@@ -790,44 +932,21 @@ static int ltr553_process_data(struct ltr553_data *ltr, int als_ps)
		}

		ltr->last_als = lux;
		/* Set up threshold */
		tmp = als_data[2] \| (als_data[3] << 8);
		if ((ch0data == 0) && (ch1data == 0)) {
		adc = 1;
		} else {
		ratio = ch1data * 100 / (ch0data + ch1data);
		dev_dbg(&ltr->i2c->dev, "ratio:%d\n", ratio);
		adc = ltr553_calc_adc(ratio, ltr->als_sensitivity,
		als_gain_table[ltr->als_gain], als_int_fac);
		}

		dev_dbg(&ltr->i2c->dev, "adc:%d\n", adc);
		dev_dbg(&ltr->i2c->dev, "previous als_gain:%d\n",
		ltr->als_gain);

		/* upper threshold */
		if (tmp + adc > ALS_DATA_MASK) {
		als_data[0] = 0xff;
		als_data[1] = 0xff;
		} else {
		als_data[0] = ALS_LOW_BYTE(tmp + adc);
		als_data[1] = ALS_HIGH_BYTE(tmp + adc);
		}

		/* lower threshold */
		if (tmp < adc) {
		als_data[2] = 0x0;
		als_data[3] = 0x0;
		} else {
		als_data[2] = ALS_LOW_BYTE(tmp - adc);
		als_data[3] = ALS_HIGH_BYTE(tmp - adc);
		}

		rc = regmap_bulk_write(ltr->regmap, LTR553_REG_ALS_THRES_UP_0,
		als_data, 4);
		rc = ltr553_als_update_setting(ltr, ch0data, ch1data,
		als_int_fac);
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_ALS_THRES_UP_0, rc);
		dev_err(&ltr->i2c->dev, "update setting failed\n");
		goto exit;
		}

		dev_dbg(&ltr->i2c->dev, "new als_gain:%d\n",
		ltr->als_gain);


		} else { /* process ps value */
		rc = regmap_bulk_read(ltr->regmap, LTR553_REG_PS_DATA_0,
		ps_data, 2);
		@@ -1035,7 +1154,7 @@ static int ltr553_enable_ps(struct ltr553_data *ltr, int enable)
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_PS_CTL, rc);
		return rc;
		goto exit;
		}

		ltr->ps_enabled = false;
		@@ -1103,14 +1222,14 @@ static int ltr553_enable_als(struct ltr553_data *ltr, int enable)
		if (rc) {
		dev_err(&ltr->i2c->dev, "write %d failed.(%d)\n",
		LTR553_REG_ALS_CTL, rc);
		return rc;
		goto exit;
		}

		ltr->als_enabled = false;
		}

		exit:
		return 0;
		return rc;
		}

		static void ltr553_als_enable_work(struct work_struct *work)