--- /dev/null
+/*
+ * drivers/i2c/chips/tsl2563.c
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Written by Timo O. Karjalainen <timo.o.karjalainen@nokia.com>
+ * Contact: Mathias Nyman <mathias.nyman@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/hwmon.h>
+#include <linux/err.h>
+#include <mach/board.h>
+
+#define DRIVER_NAME "tsl2563"
+
+/* Use this many bits for fraction part. */
+#define ADC_FRAC_BITS (14)
+
+/* Given number of 1/10000's in ADC_FRAC_BITS precision. */
+#define FRAC10K(f) (((f) * (1L << (ADC_FRAC_BITS))) / (10000))
+
+/* Bits used for fraction in calibration coefficients.*/
+#define CALIB_FRAC_BITS (10)
+/* 0.5 in CALIB_FRAC_BITS precision */
+#define CALIB_FRAC_HALF (1 << (CALIB_FRAC_BITS - 1))
+/* Make a fraction from a number n that was multiplied with b. */
+#define CALIB_FRAC(n, b) (((n) << CALIB_FRAC_BITS) / (b))
+/* Decimal 10^(digits in sysfs presentation) */
+#define CALIB_BASE_SYSFS (1000)
+
+#define TSL2563_CMD (0x80)
+#define TSL2563_CLEARINT (0x40)
+
+#define TSL2563_REG_CTRL (0x00)
+#define TSL2563_REG_TIMING (0x01)
+#define TSL2563_REG_LOWLOW (0x02) /* data0 low threshold, 2 bytes */
+#define TSL2563_REG_LOWHIGH (0x03)
+#define TSL2563_REG_HIGHLOW (0x04) /* data0 high threshold, 2 bytes */
+#define TSL2563_REG_HIGHHIGH (0x05)
+#define TSL2563_REG_INT (0x06)
+#define TSL2563_REG_ID (0x0a)
+#define TSL2563_REG_DATA0LOW (0x0c) /* broadband sensor value, 2 bytes */
+#define TSL2563_REG_DATA0HIGH (0x0d)
+#define TSL2563_REG_DATA1LOW (0x0e) /* infrared sensor value, 2 bytes */
+#define TSL2563_REG_DATA1HIGH (0x0f)
+
+#define TSL2563_CMD_POWER_ON (0x03)
+#define TSL2563_CMD_POWER_OFF (0x00)
+#define TSL2563_CTRL_POWER_MASK (0x03)
+
+#define TSL2563_TIMING_13MS (0x00)
+#define TSL2563_TIMING_100MS (0x01)
+#define TSL2563_TIMING_400MS (0x02)
+#define TSL2563_TIMING_MASK (0x03)
+#define TSL2563_TIMING_GAIN16 (0x10)
+#define TSL2563_TIMING_GAIN1 (0x00)
+
+#define TSL2563_INT_DISBLED (0x00)
+#define TSL2563_INT_LEVEL (0x10)
+#define TSL2563_INT_PERSIST(n) ((n) & 0x0F)
+
+struct tsl2563_gainlevel_coeff {
+ u8 gaintime;
+ u16 min;
+ u16 max;
+};
+
+static struct tsl2563_gainlevel_coeff tsl2563_gainlevel_table[] = {
+ {
+ .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN16,
+ .min = 0,
+ .max = 65534,
+ }, {
+ .gaintime = TSL2563_TIMING_400MS | TSL2563_TIMING_GAIN1,
+ .min = 2048,
+ .max = 65534,
+ }, {
+ .gaintime = TSL2563_TIMING_100MS | TSL2563_TIMING_GAIN1,
+ .min = 4095,
+ .max = 37177,
+ }, {
+ .gaintime = TSL2563_TIMING_13MS | TSL2563_TIMING_GAIN1,
+ .min = 3000,
+ .max = 65535,
+ },
+};
+
+struct tsl2563_chip {
+ struct mutex lock;
+ struct i2c_client *client;
+ struct device *hwmon_dev;
+
+ /* Remember state for suspend and resume functions */
+ pm_message_t state;
+
+ struct tsl2563_gainlevel_coeff *gainlevel;
+
+ /* Thresholds are in lux */
+ u16 low_thres;
+ u16 high_thres;
+ u8 intr;
+
+ /* Calibration coefficients */
+ u32 calib0;
+ u32 calib1;
+
+ /* Cache current values, to be returned while suspended */
+ u32 data0;
+ u32 data1;
+};
+
+static int tsl2563_write(struct i2c_client *client, u8 reg, u8 value)
+{
+ int ret;
+ u8 buf[2];
+
+ buf[0] = TSL2563_CMD | reg;
+ buf[1] = value;
+
+ ret = i2c_master_send(client, buf, sizeof(buf));
+ return (ret == sizeof(buf)) ? 0 : ret;
+}
+
+static int tsl2563_read(struct i2c_client *client, u8 reg, void *buf, int len)
+{
+ int ret;
+ u8 cmd = TSL2563_CMD | reg;
+
+ ret = i2c_master_send(client, &cmd, sizeof(cmd));
+ if (ret != sizeof(cmd))
+ return ret;
+
+ return i2c_master_recv(client, buf, len);
+}
+
+static int tsl2563_set_power(struct tsl2563_chip *chip, int on)
+{
+ struct i2c_client *client = chip->client;
+ u8 cmd;
+
+ cmd = on ? TSL2563_CMD_POWER_ON : TSL2563_CMD_POWER_OFF;
+ return tsl2563_write(client, TSL2563_REG_CTRL, cmd);
+}
+
+/*
+ * Return value is 0 for off, 1 for on, or a negative error
+ * code if reading failed.
+ */
+static int tsl2563_get_power(struct tsl2563_chip *chip)
+{
+ struct i2c_client *client = chip->client;
+ int ret;
+ u8 val;
+
+ ret = tsl2563_read(client, TSL2563_REG_CTRL, &val, sizeof(val));
+ if (ret != sizeof(val))
+ return ret;
+
+ return (val & TSL2563_CTRL_POWER_MASK) == TSL2563_CMD_POWER_ON;
+}
+
+static int tsl2563_configure(struct tsl2563_chip *chip)
+{
+ struct i2c_client *client = chip->client;
+ int ret;
+
+ ret = tsl2563_write(client, TSL2563_REG_TIMING,
+ chip->gainlevel->gaintime);
+ if (ret)
+ goto out;
+
+ ret = tsl2563_write(client, TSL2563_REG_INT, chip->intr);
+
+out:
+ return ret;
+}
+
+static int tsl2563_detect(struct tsl2563_chip *chip)
+{
+ int ret;
+
+ ret = tsl2563_set_power(chip, 1);
+ if (ret)
+ return ret;
+
+ ret = tsl2563_get_power(chip);
+ if (ret < 0)
+ return ret;
+
+ return ret ? 0 : -ENODEV;
+}
+
+static int tsl2563_read_id(struct tsl2563_chip *chip, u8 *id)
+{
+ struct i2c_client *client = chip->client;
+ int ret;
+
+ ret = tsl2563_read(client, TSL2563_REG_ID, id, sizeof(*id));
+ if (ret != sizeof(*id))
+ return ret;
+
+ return 0;
+}
+
+/*
+ * "Normalized" ADC value is one obtained with 400ms of integration time and
+ * 16x gain. This function returns the number of bits of shift needed to
+ * convert between normalized values and HW values obtained using given
+ * timing and gain settings.
+ */
+static int adc_shiftbits(u8 timing)
+{
+ int shift = 0;
+
+ switch (timing & TSL2563_TIMING_MASK) {
+ case TSL2563_TIMING_13MS:
+ shift += 5;
+ break;
+ case TSL2563_TIMING_100MS:
+ shift += 2;
+ break;
+ case TSL2563_TIMING_400MS:
+ /* no-op */
+ break;
+ }
+
+ if (!(timing & TSL2563_TIMING_GAIN16))
+ shift += 4;
+
+ return shift;
+}
+
+/* Convert a HW ADC value to normalized scale. */
+static u32 normalize_adc(u16 adc, u8 timing)
+{
+ return adc << adc_shiftbits(timing);
+}
+
+static void tsl2563_wait_adc(struct tsl2563_chip *chip)
+{
+ unsigned int delay;
+
+ switch (chip->gainlevel->gaintime & TSL2563_TIMING_MASK) {
+ case TSL2563_TIMING_13MS:
+ delay = 14;
+ break;
+ case TSL2563_TIMING_100MS:
+ delay = 101;
+ break;
+ default:
+ delay = 402;
+ }
+ /*
+ * TODO: Make sure that we wait at least required delay but why we
+ * have to extend it one tick more?
+ */
+ schedule_timeout_interruptible(msecs_to_jiffies(delay) + 2);
+}
+
+static int tsl2563_adjust_gainlevel(struct tsl2563_chip *chip, u16 adc)
+{
+ struct i2c_client *client = chip->client;
+
+ if (adc > chip->gainlevel->max || adc < chip->gainlevel->min) {
+
+ (adc > chip->gainlevel->max) ?
+ chip->gainlevel++ : chip->gainlevel--;
+
+ tsl2563_write(client, TSL2563_REG_TIMING,
+ chip->gainlevel->gaintime);
+
+ tsl2563_wait_adc(chip);
+ tsl2563_wait_adc(chip);
+
+ return 1;
+ } else
+ return 0;
+}
+
+static int tsl2563_get_adc(struct tsl2563_chip *chip)
+{
+ struct i2c_client *client = chip->client;
+ u8 buf0[2], buf1[2];
+ u16 adc0, adc1;
+ int retry = 1;
+ int ret = 0;
+
+ if (chip->state.event != PM_EVENT_ON)
+ goto out;
+
+ while (retry) {
+ ret = tsl2563_read(client,
+ TSL2563_REG_DATA0LOW | TSL2563_CLEARINT,
+ buf0, sizeof(buf0));
+ if (ret != sizeof(buf0))
+ goto out;
+
+ ret = tsl2563_read(client, TSL2563_REG_DATA1LOW,
+ buf1, sizeof(buf1));
+ if (ret != sizeof(buf1))
+ goto out;
+
+ adc0 = (buf0[1] << 8) + buf0[0];
+ adc1 = (buf1[1] << 8) + buf1[0];
+
+ retry = tsl2563_adjust_gainlevel(chip, adc0);
+ }
+
+ chip->data0 = normalize_adc(adc0, chip->gainlevel->gaintime);
+ chip->data1 = normalize_adc(adc1, chip->gainlevel->gaintime);
+
+ ret = 0;
+out:
+ return ret;
+}
+
+static inline int calib_to_sysfs(u32 calib)
+{
+ return (int) (((calib * CALIB_BASE_SYSFS) +
+ CALIB_FRAC_HALF) >> CALIB_FRAC_BITS);
+}
+
+static inline u32 calib_from_sysfs(int value)
+{
+ return (((u32) value) << CALIB_FRAC_BITS) / CALIB_BASE_SYSFS;
+}
+
+/*
+ * Conversions between lux and ADC values.
+ *
+ * The basic formula is lux = c0 * adc0 - c1 * adc1, where c0 and c1 are
+ * appropriate constants. Different constants are needed for different
+ * kinds of light, determined by the ratio adc1/adc0 (basically the ratio
+ * of the intensities in infrared and visible wavelengths). lux_table below
+ * lists the upper threshold of the adc1/adc0 ratio and the corresponding
+ * constants.
+ */
+
+struct tsl2563_lux_coeff {
+ unsigned long ch_ratio;
+ unsigned long ch0_coeff;
+ unsigned long ch1_coeff;
+};
+
+static const struct tsl2563_lux_coeff lux_table[] = {
+ {
+ .ch_ratio = FRAC10K(1300),
+ .ch0_coeff = FRAC10K(315),
+ .ch1_coeff = FRAC10K(262),
+ }, {
+ .ch_ratio = FRAC10K(2600),
+ .ch0_coeff = FRAC10K(337),
+ .ch1_coeff = FRAC10K(430),
+ }, {
+ .ch_ratio = FRAC10K(3900),
+ .ch0_coeff = FRAC10K(363),
+ .ch1_coeff = FRAC10K(529),
+ }, {
+ .ch_ratio = FRAC10K(5200),
+ .ch0_coeff = FRAC10K(392),
+ .ch1_coeff = FRAC10K(605),
+ }, {
+ .ch_ratio = FRAC10K(6500),
+ .ch0_coeff = FRAC10K(229),
+ .ch1_coeff = FRAC10K(291),
+ }, {
+ .ch_ratio = FRAC10K(8000),
+ .ch0_coeff = FRAC10K(157),
+ .ch1_coeff = FRAC10K(180),
+ }, {
+ .ch_ratio = FRAC10K(13000),
+ .ch0_coeff = FRAC10K(34),
+ .ch1_coeff = FRAC10K(26),
+ }, {
+ .ch_ratio = ULONG_MAX,
+ .ch0_coeff = 0,
+ .ch1_coeff = 0,
+ },
+};
+
+/*
+ * Convert normalized, scaled ADC values to lux.
+ */
+static unsigned int adc_to_lux(u32 adc0, u32 adc1)
+{
+ const struct tsl2563_lux_coeff *lp = lux_table;
+ unsigned long ratio, lux, ch0 = adc0, ch1 = adc1;
+
+ ratio = ch0 ? ((ch1 << ADC_FRAC_BITS) / ch0) : ULONG_MAX;
+
+ while (lp->ch_ratio < ratio)
+ lp++;
+
+ lux = ch0 * lp->ch0_coeff - ch1 * lp->ch1_coeff;
+
+ return (unsigned int) (lux >> ADC_FRAC_BITS);
+}
+
+/*--------------------------------------------------------------*/
+/* Sysfs interface */
+/*--------------------------------------------------------------*/
+
+static ssize_t tsl2563_adc0_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = tsl2563_get_adc(chip);
+ if (ret)
+ return ret;
+
+ ret = snprintf(buf, PAGE_SIZE, "%d\n", chip->data0);
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+
+static ssize_t tsl2563_adc1_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = tsl2563_get_adc(chip);
+ if (ret)
+ return ret;
+
+ ret = snprintf(buf, PAGE_SIZE, "%d\n", chip->data1);
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+
+/* Apply calibration coefficient to ADC count. */
+static u32 calib_adc(u32 adc, u32 calib)
+{
+ unsigned long scaled = adc;
+
+ scaled *= calib;
+ scaled >>= CALIB_FRAC_BITS;
+
+ return (u32) scaled;
+}
+
+static ssize_t tsl2563_lux_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ u32 calib0, calib1;
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = tsl2563_get_adc(chip);
+ if (ret)
+ goto out;
+
+ calib0 = calib_adc(chip->data0, chip->calib0);
+ calib1 = calib_adc(chip->data1, chip->calib1);
+
+ ret = snprintf(buf, PAGE_SIZE, "%d\n", adc_to_lux(calib0, calib1));
+
+out:
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static ssize_t format_calib(char *buf, int len, u32 calib)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", calib_to_sysfs(calib));
+}
+
+static ssize_t tsl2563_calib0_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+ ret = format_calib(buf, PAGE_SIZE, chip->calib0);
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static ssize_t tsl2563_calib1_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+ ret = format_calib(buf, PAGE_SIZE, chip->calib1);
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static int do_calib_store(struct device *dev, const char *buf, size_t len,
+ int ch)
+{
+ struct tsl2563_chip *chip = dev_get_drvdata(dev);
+ int value;
+ u32 calib;
+
+ if (1 != sscanf(buf, "%d", &value))
+ return -EINVAL;
+
+ calib = calib_from_sysfs(value);
+
+ if (ch)
+ chip->calib1 = calib;
+ else
+ chip->calib0 = calib;
+
+ return len;
+}
+
+static ssize_t tsl2563_calib0_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ return do_calib_store(dev, buf, len, 0);
+}
+
+static ssize_t tsl2563_calib1_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ return do_calib_store(dev, buf, len, 1);
+}
+
+static DEVICE_ATTR(adc0, S_IRUGO, tsl2563_adc0_show, NULL);
+static DEVICE_ATTR(adc1, S_IRUGO, tsl2563_adc1_show, NULL);
+static DEVICE_ATTR(lux, S_IRUGO, tsl2563_lux_show, NULL);
+static DEVICE_ATTR(calib0, S_IRUGO | S_IWUSR,
+ tsl2563_calib0_show, tsl2563_calib0_store);
+static DEVICE_ATTR(calib1, S_IRUGO | S_IWUSR,
+ tsl2563_calib1_show, tsl2563_calib1_store);
+
+static struct attribute *tsl2563_attributes[] = {
+ &dev_attr_adc0.attr,
+ &dev_attr_adc1.attr,
+ &dev_attr_lux.attr,
+ &dev_attr_calib0.attr,
+ &dev_attr_calib1.attr,
+ NULL
+};
+
+static const struct attribute_group tsl2563_group = {
+ .attrs = tsl2563_attributes,
+};
+
+static int tsl2563_register_sysfs(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+
+ return sysfs_create_group(&dev->kobj, &tsl2563_group);
+}
+
+static void tsl2563_unregister_sysfs(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+
+ sysfs_remove_group(&dev->kobj, &tsl2563_group);
+}
+
+/*--------------------------------------------------------------*/
+/* Probe, Attach, Remove */
+/*--------------------------------------------------------------*/
+static struct i2c_driver tsl2563_i2c_driver;
+
+static int tsl2563_probe(struct i2c_client *client,
+ const struct i2c_device_id *device_id)
+{
+ struct tsl2563_chip *chip;
+ int err = 0;
+ u8 id;
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, chip);
+ chip->client = client;
+
+ err = tsl2563_detect(chip);
+ if (err) {
+ dev_err(&client->dev, "device not found, error %d \n", -err);
+ goto fail1;
+ }
+
+ err = tsl2563_read_id(chip, &id);
+ if (err)
+ goto fail1;
+
+ mutex_init(&chip->lock);
+
+ /* Default values used until userspace says otherwise */
+ chip->low_thres = 0x0;
+ chip->high_thres = 0xffff;
+ chip->gainlevel = tsl2563_gainlevel_table;
+ chip->intr = TSL2563_INT_PERSIST(4);
+ chip->calib0 = calib_from_sysfs(CALIB_BASE_SYSFS);
+ chip->calib1 = calib_from_sysfs(CALIB_BASE_SYSFS);
+
+ dev_info(&client->dev, "model %d, rev. %d\n", id >> 4, id & 0x0f);
+
+ err = tsl2563_configure(chip);
+ if (err)
+ goto fail1;
+
+ chip->hwmon_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(chip->hwmon_dev))
+ goto fail1;
+
+ err = tsl2563_register_sysfs(client);
+ if (err) {
+ dev_err(&client->dev, "sysfs registration failed, %d\n", err);
+ goto fail2;
+ }
+
+ return 0;
+fail2:
+ hwmon_device_unregister(chip->hwmon_dev);
+fail1:
+ kfree(chip);
+ return err;
+}
+
+static int tsl2563_remove(struct i2c_client *client)
+{
+ struct tsl2563_chip *chip = i2c_get_clientdata(client);
+
+ tsl2563_unregister_sysfs(client);
+ hwmon_device_unregister(chip->hwmon_dev);
+
+ kfree(chip);
+ return 0;
+}
+
+static int tsl2563_suspend(struct i2c_client *client, pm_message_t state)
+{
+ struct tsl2563_chip *chip = i2c_get_clientdata(client);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = tsl2563_set_power(chip, 0);
+ if (ret)
+ goto out;
+
+ chip->state = state;
+
+out:
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static int tsl2563_resume(struct i2c_client *client)
+{
+ struct tsl2563_chip *chip = i2c_get_clientdata(client);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = tsl2563_set_power(chip, 1);
+ if (ret)
+ goto out;
+
+ ret = tsl2563_configure(chip);
+ if (ret)
+ goto out;
+
+ chip->state.event = PM_EVENT_ON;
+
+out:
+ mutex_unlock(&chip->lock);
+ return ret;
+}
+
+static const struct i2c_device_id tsl2563_id[] = {
+ { DRIVER_NAME, 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, tsl2563_id);
+
+static struct i2c_driver tsl2563_i2c_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ },
+ .suspend = tsl2563_suspend,
+ .resume = tsl2563_resume,
+ .probe = tsl2563_probe,
+ .remove = __devexit_p(tsl2563_remove),
+ .id_table = tsl2563_id,
+};
+
+static int __init tsl2563_init(void)
+{
+ return i2c_add_driver(&tsl2563_i2c_driver);
+}
+
+static void __exit tsl2563_exit(void)
+{
+ i2c_del_driver(&tsl2563_i2c_driver);
+}
+
+MODULE_AUTHOR("Nokia Corporation");
+MODULE_DESCRIPTION("tsl2563 light sensor driver");
+MODULE_LICENSE("GPL");
+
+module_init(tsl2563_init);
+module_exit(tsl2563_exit);
projects / linux-2.6-omap-h63xx.git / blobdiff