[PATCH v4 19/26] staging: iio: tsl2583: move from a global to a per device lux table

From: Brian Masney
Date: Sat Nov 12 2016 - 13:21:35 EST


The driver contains a global lux table that can be updated via sysfs.
Change this to a per device lux table so that multiple devices can be
hooked up to the same system with different lux tables.

There are 10 entries, plus 1 for the termination segment, set aside for
the entries in the lux table. When updating the lux table via sysfs,
only 9 entries, plus the terminator, could be added. This changes
the code to allow for the 10 entries, plus the terminator.

Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx>
---
drivers/staging/iio/light/tsl2583.c | 80 +++++++++++++++++++++----------------
1 file changed, 46 insertions(+), 34 deletions(-)

diff --git a/drivers/staging/iio/light/tsl2583.c b/drivers/staging/iio/light/tsl2583.c
index 78967dc..3818ffa 100644
--- a/drivers/staging/iio/light/tsl2583.c
+++ b/drivers/staging/iio/light/tsl2583.c
@@ -70,11 +70,34 @@ struct tsl2583_als_info {
u16 lux;
};

+struct tsl2583_lux {
+ unsigned int ratio;
+ unsigned int ch0;
+ unsigned int ch1;
+};
+
+static const struct tsl2583_lux tsl2583_default_lux[] = {
+ { 9830, 8520, 15729 },
+ { 12452, 10807, 23344 },
+ { 14746, 6383, 11705 },
+ { 17695, 4063, 6554 },
+ { 0, 0, 0 } /* Termination segment */
+};
+
+#define TSL2583_MAX_LUX_TABLE_ENTRIES 11
+
struct tsl2583_settings {
int als_time;
int als_gain;
int als_gain_trim;
int als_cal_target;
+
+ /*
+ * This structure is intentionally large to accommodate updates via
+ * sysfs. Sized to 11 = max 10 segments + 1 termination segment.
+ * Assumption is that one and only one type of glass used.
+ */
+ struct tsl2583_lux als_device_lux[TSL2583_MAX_LUX_TABLE_ENTRIES];
};

struct tsl2583_chip {
@@ -87,24 +110,6 @@ struct tsl2583_chip {
bool suspended;
};

-struct tsl2583_lux {
- unsigned int ratio;
- unsigned int ch0;
- unsigned int ch1;
-};
-
-/*
- * This structure is intentionally large to accommodate updates via sysfs.
- * Sized to 11 = max 10 segments + 1 termination segment. Assumption is that
- * one and only one type of glass used.
- */
-static struct tsl2583_lux tsl2583_device_lux[11] = {
- { 9830, 8520, 15729 },
- { 12452, 10807, 23344 },
- { 14746, 6383, 11705 },
- { 17695, 4063, 6554 },
-};
-
struct gainadj {
s16 ch0;
s16 ch1;
@@ -142,6 +147,10 @@ static void tsl2583_defaults(struct tsl2583_chip *chip)

/* Known external ALS reading used for calibration */
chip->als_settings.als_cal_target = 130;
+
+ /* Default lux table. */
+ memcpy(chip->als_settings.als_device_lux, tsl2583_default_lux,
+ sizeof(tsl2583_default_lux));
}

/*
@@ -151,7 +160,7 @@ static void tsl2583_defaults(struct tsl2583_chip *chip)
* Time scale factor array values are adjusted based on the integration time.
* The raw values are multiplied by a scale factor, and device gain is obtained
* using gain index. Limit checks are done next, then the ratio of a multiple
- * of ch1 value, to the ch0 value, is calculated. The array tsl2583_device_lux[]
+ * of ch1 value, to the ch0 value, is calculated. The array als_device_lux[]
* declared above is then scanned to find the first ratio value that is just
* above the ratio we just calculated. The ch0 and ch1 multiplier constants in
* the array are then used along with the time scale factor array values, to
@@ -233,7 +242,7 @@ static int tsl2583_get_lux(struct iio_dev *indio_dev)
ratio = (ch1 << 15) / ch0;

/* convert to unscaled lux using the pointer to the table */
- for (p = (struct tsl2583_lux *)tsl2583_device_lux;
+ for (p = (struct tsl2583_lux *)chip->als_settings.als_device_lux;
p->ratio != 0 && p->ratio < ratio; p++)
;

@@ -270,7 +279,7 @@ static int tsl2583_get_lux(struct iio_dev *indio_dev)

/*
* Adjust for active gain scale.
- * The tsl2583_device_lux tables above have a factor of 8192 built in,
+ * The tsl2583_default_lux tables above have a factor of 8192 built in,
* so we need to shift right.
* User-specified gain provides a multiplier.
* Apply user-specified gain before shifting right to retain precision.
@@ -522,15 +531,17 @@ static ssize_t in_illuminance_lux_table_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct tsl2583_chip *chip = iio_priv(indio_dev);
unsigned int i;
int offset = 0;

- for (i = 0; i < ARRAY_SIZE(tsl2583_device_lux); i++) {
+ for (i = 0; i < ARRAY_SIZE(chip->als_settings.als_device_lux); i++) {
offset += sprintf(buf + offset, "%u,%u,%u,",
- tsl2583_device_lux[i].ratio,
- tsl2583_device_lux[i].ch0,
- tsl2583_device_lux[i].ch1);
- if (tsl2583_device_lux[i].ratio == 0) {
+ chip->als_settings.als_device_lux[i].ratio,
+ chip->als_settings.als_device_lux[i].ch0,
+ chip->als_settings.als_device_lux[i].ch1);
+ if (chip->als_settings.als_device_lux[i].ratio == 0) {
/*
* We just printed the first "0" entry.
* Now get rid of the extra "," and break.
@@ -545,15 +556,14 @@ static ssize_t in_illuminance_lux_table_show(struct device *dev,
return offset;
}

-#define TSL2583_MAX_LUX_INTS ((ARRAY_SIZE(tsl2583_device_lux) - 1) * 3)
-
static ssize_t in_illuminance_lux_table_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct tsl2583_chip *chip = iio_priv(indio_dev);
- int value[ARRAY_SIZE(tsl2583_device_lux) * 3 + 1];
+ const unsigned int max_ints = TSL2583_MAX_LUX_TABLE_ENTRIES * 3;
+ int value[TSL2583_MAX_LUX_TABLE_ENTRIES * 3];
int ret = -EINVAL;
unsigned int n;

@@ -568,10 +578,10 @@ static ssize_t in_illuminance_lux_table_store(struct device *dev,
* and the last table entry is all 0.
*/
n = value[0];
- if ((n % 3) || n < 6 || n > TSL2583_MAX_LUX_INTS) {
+ if ((n % 3) || n < 6 || n > max_ints) {
dev_err(dev,
- "%s: The number of entries in the lux table must be a multiple of 3 and within the range [6, %zu]\n",
- __func__, TSL2583_MAX_LUX_INTS);
+ "%s: The number of entries in the lux table must be a multiple of 3 and within the range [6, %d]\n",
+ __func__, max_ints);
goto done;
}
if ((value[n - 2] | value[n - 1] | value[n]) != 0) {
@@ -581,8 +591,10 @@ static ssize_t in_illuminance_lux_table_store(struct device *dev,
}

/* Zero out the table */
- memset(tsl2583_device_lux, 0, sizeof(tsl2583_device_lux));
- memcpy(tsl2583_device_lux, &value[1], value[0] * sizeof(value[1]));
+ memset(chip->als_settings.als_device_lux, 0,
+ sizeof(chip->als_settings.als_device_lux));
+ memcpy(chip->als_settings.als_device_lux, &value[1],
+ value[0] * sizeof(value[1]));

ret = len;

--
2.7.4