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@@ -1,6 +1,10 @@
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/*
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/*
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* sht15.c - support for the SHT15 Temperature and Humidity Sensor
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* sht15.c - support for the SHT15 Temperature and Humidity Sensor
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*
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*
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+ * Portions Copyright (c) 2010-2011 Savoir-faire Linux Inc.
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+ * Jerome Oufella <jerome.oufella@savoirfairelinux.com>
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+ * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
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+ *
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* Copyright (c) 2009 Jonathan Cameron
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* Copyright (c) 2009 Jonathan Cameron
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*
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*
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* Copyright (c) 2007 Wouter Horre
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* Copyright (c) 2007 Wouter Horre
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@@ -9,16 +13,7 @@
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* it under the terms of the GNU General Public License version 2 as
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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* published by the Free Software Foundation.
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*
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*
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- * Currently ignoring checksum on readings.
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- * Default resolution only (14bit temp, 12bit humidity)
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- * Ignoring battery status.
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- * Heater not enabled.
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- * Timings are all conservative.
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- *
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- * Data sheet available (1/2009) at
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- * http://www.sensirion.ch/en/pdf/product_information/Datasheet-humidity-sensor-SHT1x.pdf
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- *
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- * Regulator supply name = vcc
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+ * For further information, see the Documentation/hwmon/sht15 file.
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*/
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*/
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#include <linux/interrupt.h>
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#include <linux/interrupt.h>
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@@ -39,17 +34,31 @@
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#include <linux/slab.h>
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#include <linux/slab.h>
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#include <asm/atomic.h>
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#include <asm/atomic.h>
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-#define SHT15_MEASURE_TEMP 3
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-#define SHT15_MEASURE_RH 5
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-
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-#define SHT15_READING_NOTHING 0
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-#define SHT15_READING_TEMP 1
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-#define SHT15_READING_HUMID 2
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-
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-/* Min timings in nsecs */
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-#define SHT15_TSCKL 100 /* clock low */
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-#define SHT15_TSCKH 100 /* clock high */
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-#define SHT15_TSU 150 /* data setup time */
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+/* Commands */
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+#define SHT15_MEASURE_TEMP 0x03
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+#define SHT15_MEASURE_RH 0x05
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+#define SHT15_WRITE_STATUS 0x06
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+#define SHT15_READ_STATUS 0x07
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+#define SHT15_SOFT_RESET 0x1E
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+
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+/* Min timings */
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+#define SHT15_TSCKL 100 /* (nsecs) clock low */
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+#define SHT15_TSCKH 100 /* (nsecs) clock high */
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+#define SHT15_TSU 150 /* (nsecs) data setup time */
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+#define SHT15_TSRST 11 /* (msecs) soft reset time */
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+
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+/* Status Register Bits */
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+#define SHT15_STATUS_LOW_RESOLUTION 0x01
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+#define SHT15_STATUS_NO_OTP_RELOAD 0x02
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+#define SHT15_STATUS_HEATER 0x04
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+#define SHT15_STATUS_LOW_BATTERY 0x40
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+
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+/* Actions the driver may be doing */
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+enum sht15_state {
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+ SHT15_READING_NOTHING,
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+ SHT15_READING_TEMP,
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+ SHT15_READING_HUMID
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+};
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/**
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/**
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* struct sht15_temppair - elements of voltage dependent temp calc
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* struct sht15_temppair - elements of voltage dependent temp calc
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@@ -61,9 +70,7 @@ struct sht15_temppair {
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int d1;
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int d1;
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};
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};
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-/* Table 9 from data sheet - relates temperature calculation
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- * to supply voltage.
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- */
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+/* Table 9 from datasheet - relates temperature calculation to supply voltage */
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static const struct sht15_temppair temppoints[] = {
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static const struct sht15_temppair temppoints[] = {
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{ 2500000, -39400 },
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{ 2500000, -39400 },
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{ 3000000, -39600 },
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{ 3000000, -39600 },
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@@ -72,29 +79,70 @@ static const struct sht15_temppair temppoints[] = {
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{ 5000000, -40100 },
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{ 5000000, -40100 },
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};
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};
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+/* Table from CRC datasheet, section 2.4 */
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+static const u8 sht15_crc8_table[] = {
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+ 0, 49, 98, 83, 196, 245, 166, 151,
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+ 185, 136, 219, 234, 125, 76, 31, 46,
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+ 67, 114, 33, 16, 135, 182, 229, 212,
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+ 250, 203, 152, 169, 62, 15, 92, 109,
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+ 134, 183, 228, 213, 66, 115, 32, 17,
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+ 63, 14, 93, 108, 251, 202, 153, 168,
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+ 197, 244, 167, 150, 1, 48, 99, 82,
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+ 124, 77, 30, 47, 184, 137, 218, 235,
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+ 61, 12, 95, 110, 249, 200, 155, 170,
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+ 132, 181, 230, 215, 64, 113, 34, 19,
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+ 126, 79, 28, 45, 186, 139, 216, 233,
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+ 199, 246, 165, 148, 3, 50, 97, 80,
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+ 187, 138, 217, 232, 127, 78, 29, 44,
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+ 2, 51, 96, 81, 198, 247, 164, 149,
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+ 248, 201, 154, 171, 60, 13, 94, 111,
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+ 65, 112, 35, 18, 133, 180, 231, 214,
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+ 122, 75, 24, 41, 190, 143, 220, 237,
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+ 195, 242, 161, 144, 7, 54, 101, 84,
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+ 57, 8, 91, 106, 253, 204, 159, 174,
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+ 128, 177, 226, 211, 68, 117, 38, 23,
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+ 252, 205, 158, 175, 56, 9, 90, 107,
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+ 69, 116, 39, 22, 129, 176, 227, 210,
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+ 191, 142, 221, 236, 123, 74, 25, 40,
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+ 6, 55, 100, 85, 194, 243, 160, 145,
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+ 71, 118, 37, 20, 131, 178, 225, 208,
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+ 254, 207, 156, 173, 58, 11, 88, 105,
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+ 4, 53, 102, 87, 192, 241, 162, 147,
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+ 189, 140, 223, 238, 121, 72, 27, 42,
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+ 193, 240, 163, 146, 5, 52, 103, 86,
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+ 120, 73, 26, 43, 188, 141, 222, 239,
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+ 130, 179, 224, 209, 70, 119, 36, 21,
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+ 59, 10, 89, 104, 255, 206, 157, 172
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+};
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+
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/**
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/**
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* struct sht15_data - device instance specific data
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* struct sht15_data - device instance specific data
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- * @pdata: platform data (gpio's etc)
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- * @read_work: bh of interrupt handler
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- * @wait_queue: wait queue for getting values from device
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- * @val_temp: last temperature value read from device
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- * @val_humid: last humidity value read from device
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- * @flag: status flag used to identify what the last request was
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- * @valid: are the current stored values valid (start condition)
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- * @last_updat: time of last update
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- * @read_lock: mutex to ensure only one read in progress
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- * at a time.
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- * @dev: associate device structure
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- * @hwmon_dev: device associated with hwmon subsystem
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- * @reg: associated regulator (if specified)
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- * @nb: notifier block to handle notifications of voltage changes
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- * @supply_uV: local copy of supply voltage used to allow
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- * use of regulator consumer if available
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- * @supply_uV_valid: indicates that an updated value has not yet
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- * been obtained from the regulator and so any calculations
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- * based upon it will be invalid.
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- * @update_supply_work: work struct that is used to update the supply_uV
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- * @interrupt_handled: flag used to indicate a hander has been scheduled
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+ * @pdata: platform data (gpio's etc).
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+ * @read_work: bh of interrupt handler.
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+ * @wait_queue: wait queue for getting values from device.
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+ * @val_temp: last temperature value read from device.
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+ * @val_humid: last humidity value read from device.
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+ * @val_status: last status register value read from device.
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+ * @checksum_ok: last value read from the device passed CRC validation.
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+ * @checksumming: flag used to enable the data validation with CRC.
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+ * @state: state identifying the action the driver is doing.
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+ * @measurements_valid: are the current stored measures valid (start condition).
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+ * @status_valid: is the current stored status valid (start condition).
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+ * @last_measurement: time of last measure.
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+ * @last_status: time of last status reading.
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+ * @read_lock: mutex to ensure only one read in progress at a time.
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+ * @dev: associate device structure.
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+ * @hwmon_dev: device associated with hwmon subsystem.
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+ * @reg: associated regulator (if specified).
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+ * @nb: notifier block to handle notifications of voltage
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+ * changes.
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+ * @supply_uV: local copy of supply voltage used to allow use of
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+ * regulator consumer if available.
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+ * @supply_uV_valid: indicates that an updated value has not yet been
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+ * obtained from the regulator and so any calculations
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+ * based upon it will be invalid.
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+ * @update_supply_work: work struct that is used to update the supply_uV.
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+ * @interrupt_handled: flag used to indicate a handler has been scheduled.
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*/
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*/
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struct sht15_data {
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struct sht15_data {
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struct sht15_platform_data *pdata;
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struct sht15_platform_data *pdata;
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@@ -102,20 +150,59 @@ struct sht15_data {
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wait_queue_head_t wait_queue;
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wait_queue_head_t wait_queue;
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uint16_t val_temp;
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uint16_t val_temp;
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uint16_t val_humid;
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uint16_t val_humid;
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- u8 flag;
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- u8 valid;
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- unsigned long last_updat;
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+ u8 val_status;
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+ bool checksum_ok;
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+ bool checksumming;
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+ enum sht15_state state;
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+ bool measurements_valid;
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+ bool status_valid;
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+ unsigned long last_measurement;
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+ unsigned long last_status;
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struct mutex read_lock;
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struct mutex read_lock;
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struct device *dev;
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struct device *dev;
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struct device *hwmon_dev;
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struct device *hwmon_dev;
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struct regulator *reg;
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struct regulator *reg;
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struct notifier_block nb;
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struct notifier_block nb;
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int supply_uV;
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int supply_uV;
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- int supply_uV_valid;
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+ bool supply_uV_valid;
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struct work_struct update_supply_work;
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struct work_struct update_supply_work;
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atomic_t interrupt_handled;
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atomic_t interrupt_handled;
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};
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};
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+/**
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+ * sht15_reverse() - reverse a byte
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+ * @byte: byte to reverse.
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+ */
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+static u8 sht15_reverse(u8 byte)
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+{
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+ u8 i, c;
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+
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+ for (c = 0, i = 0; i < 8; i++)
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+ c |= (!!(byte & (1 << i))) << (7 - i);
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+ return c;
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+}
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+
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+/**
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+ * sht15_crc8() - compute crc8
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+ * @data: sht15 specific data.
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+ * @value: sht15 retrieved data.
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+ *
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+ * This implements section 2 of the CRC datasheet.
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+ */
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+static u8 sht15_crc8(struct sht15_data *data,
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+ const u8 *value,
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+ int len)
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+{
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+ u8 crc = sht15_reverse(data->val_status & 0x0F);
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+
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+ while (len--) {
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+ crc = sht15_crc8_table[*value ^ crc];
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+ value++;
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+ }
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+
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+ return crc;
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+}
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+
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/**
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/**
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* sht15_connection_reset() - reset the comms interface
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* sht15_connection_reset() - reset the comms interface
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* @data: sht15 specific data
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* @data: sht15 specific data
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@@ -125,6 +212,7 @@ struct sht15_data {
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static void sht15_connection_reset(struct sht15_data *data)
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static void sht15_connection_reset(struct sht15_data *data)
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{
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{
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int i;
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int i;
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+
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gpio_direction_output(data->pdata->gpio_data, 1);
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gpio_direction_output(data->pdata->gpio_data, 1);
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ndelay(SHT15_TSCKL);
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ndelay(SHT15_TSCKL);
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gpio_set_value(data->pdata->gpio_sck, 0);
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gpio_set_value(data->pdata->gpio_sck, 0);
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@@ -136,14 +224,14 @@ static void sht15_connection_reset(struct sht15_data *data)
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ndelay(SHT15_TSCKL);
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ndelay(SHT15_TSCKL);
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}
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}
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}
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}
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+
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/**
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/**
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* sht15_send_bit() - send an individual bit to the device
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* sht15_send_bit() - send an individual bit to the device
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* @data: device state data
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* @data: device state data
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* @val: value of bit to be sent
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* @val: value of bit to be sent
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- **/
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+ */
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static inline void sht15_send_bit(struct sht15_data *data, int val)
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static inline void sht15_send_bit(struct sht15_data *data, int val)
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{
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{
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-
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gpio_set_value(data->pdata->gpio_data, val);
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gpio_set_value(data->pdata->gpio_data, val);
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ndelay(SHT15_TSU);
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ndelay(SHT15_TSU);
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gpio_set_value(data->pdata->gpio_sck, 1);
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gpio_set_value(data->pdata->gpio_sck, 1);
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@@ -154,12 +242,12 @@ static inline void sht15_send_bit(struct sht15_data *data, int val)
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/**
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/**
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* sht15_transmission_start() - specific sequence for new transmission
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* sht15_transmission_start() - specific sequence for new transmission
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- *
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* @data: device state data
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* @data: device state data
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+ *
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* Timings for this are not documented on the data sheet, so very
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* Timings for this are not documented on the data sheet, so very
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* conservative ones used in implementation. This implements
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* conservative ones used in implementation. This implements
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* figure 12 on the data sheet.
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* figure 12 on the data sheet.
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- **/
|
|
|
|
|
|
|
+ */
|
|
|
static void sht15_transmission_start(struct sht15_data *data)
|
|
static void sht15_transmission_start(struct sht15_data *data)
|
|
|
{
|
|
{
|
|
|
/* ensure data is high and output */
|
|
/* ensure data is high and output */
|
|
@@ -180,23 +268,26 @@ static void sht15_transmission_start(struct sht15_data *data)
|
|
|
gpio_set_value(data->pdata->gpio_sck, 0);
|
|
gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
ndelay(SHT15_TSCKL);
|
|
ndelay(SHT15_TSCKL);
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
/**
|
|
/**
|
|
|
* sht15_send_byte() - send a single byte to the device
|
|
* sht15_send_byte() - send a single byte to the device
|
|
|
* @data: device state
|
|
* @data: device state
|
|
|
* @byte: value to be sent
|
|
* @byte: value to be sent
|
|
|
- **/
|
|
|
|
|
|
|
+ */
|
|
|
static void sht15_send_byte(struct sht15_data *data, u8 byte)
|
|
static void sht15_send_byte(struct sht15_data *data, u8 byte)
|
|
|
{
|
|
{
|
|
|
int i;
|
|
int i;
|
|
|
|
|
+
|
|
|
for (i = 0; i < 8; i++) {
|
|
for (i = 0; i < 8; i++) {
|
|
|
sht15_send_bit(data, !!(byte & 0x80));
|
|
sht15_send_bit(data, !!(byte & 0x80));
|
|
|
byte <<= 1;
|
|
byte <<= 1;
|
|
|
}
|
|
}
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
/**
|
|
/**
|
|
|
* sht15_wait_for_response() - checks for ack from device
|
|
* sht15_wait_for_response() - checks for ack from device
|
|
|
* @data: device state
|
|
* @data: device state
|
|
|
- **/
|
|
|
|
|
|
|
+ */
|
|
|
static int sht15_wait_for_response(struct sht15_data *data)
|
|
static int sht15_wait_for_response(struct sht15_data *data)
|
|
|
{
|
|
{
|
|
|
gpio_direction_input(data->pdata->gpio_data);
|
|
gpio_direction_input(data->pdata->gpio_data);
|
|
@@ -220,27 +311,199 @@ static int sht15_wait_for_response(struct sht15_data *data)
|
|
|
*
|
|
*
|
|
|
* On entry, sck is output low, data is output pull high
|
|
* On entry, sck is output low, data is output pull high
|
|
|
* and the interrupt disabled.
|
|
* and the interrupt disabled.
|
|
|
- **/
|
|
|
|
|
|
|
+ */
|
|
|
static int sht15_send_cmd(struct sht15_data *data, u8 cmd)
|
|
static int sht15_send_cmd(struct sht15_data *data, u8 cmd)
|
|
|
{
|
|
{
|
|
|
int ret = 0;
|
|
int ret = 0;
|
|
|
|
|
+
|
|
|
sht15_transmission_start(data);
|
|
sht15_transmission_start(data);
|
|
|
sht15_send_byte(data, cmd);
|
|
sht15_send_byte(data, cmd);
|
|
|
ret = sht15_wait_for_response(data);
|
|
ret = sht15_wait_for_response(data);
|
|
|
return ret;
|
|
return ret;
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_soft_reset() - send a soft reset command
|
|
|
|
|
+ * @data: sht15 specific data.
|
|
|
|
|
+ *
|
|
|
|
|
+ * As described in section 3.2 of the datasheet.
|
|
|
|
|
+ */
|
|
|
|
|
+static int sht15_soft_reset(struct sht15_data *data)
|
|
|
|
|
+{
|
|
|
|
|
+ int ret;
|
|
|
|
|
+
|
|
|
|
|
+ ret = sht15_send_cmd(data, SHT15_SOFT_RESET);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ return ret;
|
|
|
|
|
+ msleep(SHT15_TSRST);
|
|
|
|
|
+ /* device resets default hardware status register value */
|
|
|
|
|
+ data->val_status = 0;
|
|
|
|
|
+
|
|
|
|
|
+ return ret;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_ack() - send a ack
|
|
|
|
|
+ * @data: sht15 specific data.
|
|
|
|
|
+ *
|
|
|
|
|
+ * Each byte of data is acknowledged by pulling the data line
|
|
|
|
|
+ * low for one clock pulse.
|
|
|
|
|
+ */
|
|
|
|
|
+static void sht15_ack(struct sht15_data *data)
|
|
|
|
|
+{
|
|
|
|
|
+ gpio_direction_output(data->pdata->gpio_data, 0);
|
|
|
|
|
+ ndelay(SHT15_TSU);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
+ ndelay(SHT15_TSU);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
+ ndelay(SHT15_TSU);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_data, 1);
|
|
|
|
|
+
|
|
|
|
|
+ gpio_direction_input(data->pdata->gpio_data);
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_end_transmission() - notify device of end of transmission
|
|
|
|
|
+ * @data: device state.
|
|
|
|
|
+ *
|
|
|
|
|
+ * This is basically a NAK (single clock pulse, data high).
|
|
|
|
|
+ */
|
|
|
|
|
+static void sht15_end_transmission(struct sht15_data *data)
|
|
|
|
|
+{
|
|
|
|
|
+ gpio_direction_output(data->pdata->gpio_data, 1);
|
|
|
|
|
+ ndelay(SHT15_TSU);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
+ ndelay(SHT15_TSCKH);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
+ ndelay(SHT15_TSCKL);
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_read_byte() - Read a byte back from the device
|
|
|
|
|
+ * @data: device state.
|
|
|
|
|
+ */
|
|
|
|
|
+static u8 sht15_read_byte(struct sht15_data *data)
|
|
|
|
|
+{
|
|
|
|
|
+ int i;
|
|
|
|
|
+ u8 byte = 0;
|
|
|
|
|
+
|
|
|
|
|
+ for (i = 0; i < 8; ++i) {
|
|
|
|
|
+ byte <<= 1;
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
+ ndelay(SHT15_TSCKH);
|
|
|
|
|
+ byte |= !!gpio_get_value(data->pdata->gpio_data);
|
|
|
|
|
+ gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
+ ndelay(SHT15_TSCKL);
|
|
|
|
|
+ }
|
|
|
|
|
+ return byte;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_send_status() - write the status register byte
|
|
|
|
|
+ * @data: sht15 specific data.
|
|
|
|
|
+ * @status: the byte to set the status register with.
|
|
|
|
|
+ *
|
|
|
|
|
+ * As described in figure 14 and table 5 of the datasheet.
|
|
|
|
|
+ */
|
|
|
|
|
+static int sht15_send_status(struct sht15_data *data, u8 status)
|
|
|
|
|
+{
|
|
|
|
|
+ int ret;
|
|
|
|
|
+
|
|
|
|
|
+ ret = sht15_send_cmd(data, SHT15_WRITE_STATUS);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ return ret;
|
|
|
|
|
+ gpio_direction_output(data->pdata->gpio_data, 1);
|
|
|
|
|
+ ndelay(SHT15_TSU);
|
|
|
|
|
+ sht15_send_byte(data, status);
|
|
|
|
|
+ ret = sht15_wait_for_response(data);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ return ret;
|
|
|
|
|
+
|
|
|
|
|
+ data->val_status = status;
|
|
|
|
|
+ return 0;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_update_status() - get updated status register from device if too old
|
|
|
|
|
+ * @data: device instance specific data.
|
|
|
|
|
+ *
|
|
|
|
|
+ * As described in figure 15 and table 5 of the datasheet.
|
|
|
|
|
+ */
|
|
|
|
|
+static int sht15_update_status(struct sht15_data *data)
|
|
|
|
|
+{
|
|
|
|
|
+ int ret = 0;
|
|
|
|
|
+ u8 status;
|
|
|
|
|
+ u8 previous_config;
|
|
|
|
|
+ u8 dev_checksum = 0;
|
|
|
|
|
+ u8 checksum_vals[2];
|
|
|
|
|
+ int timeout = HZ;
|
|
|
|
|
+
|
|
|
|
|
+ mutex_lock(&data->read_lock);
|
|
|
|
|
+ if (time_after(jiffies, data->last_status + timeout)
|
|
|
|
|
+ || !data->status_valid) {
|
|
|
|
|
+ ret = sht15_send_cmd(data, SHT15_READ_STATUS);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ goto error_ret;
|
|
|
|
|
+ status = sht15_read_byte(data);
|
|
|
|
|
+
|
|
|
|
|
+ if (data->checksumming) {
|
|
|
|
|
+ sht15_ack(data);
|
|
|
|
|
+ dev_checksum = sht15_reverse(sht15_read_byte(data));
|
|
|
|
|
+ checksum_vals[0] = SHT15_READ_STATUS;
|
|
|
|
|
+ checksum_vals[1] = status;
|
|
|
|
|
+ data->checksum_ok = (sht15_crc8(data, checksum_vals, 2)
|
|
|
|
|
+ == dev_checksum);
|
|
|
|
|
+ }
|
|
|
|
|
+
|
|
|
|
|
+ sht15_end_transmission(data);
|
|
|
|
|
+
|
|
|
|
|
+ /*
|
|
|
|
|
+ * Perform checksum validation on the received data.
|
|
|
|
|
+ * Specification mentions that in case a checksum verification
|
|
|
|
|
+ * fails, a soft reset command must be sent to the device.
|
|
|
|
|
+ */
|
|
|
|
|
+ if (data->checksumming && !data->checksum_ok) {
|
|
|
|
|
+ previous_config = data->val_status & 0x07;
|
|
|
|
|
+ ret = sht15_soft_reset(data);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ goto error_ret;
|
|
|
|
|
+ if (previous_config) {
|
|
|
|
|
+ ret = sht15_send_status(data, previous_config);
|
|
|
|
|
+ if (ret) {
|
|
|
|
|
+ dev_err(data->dev,
|
|
|
|
|
+ "CRC validation failed, unable "
|
|
|
|
|
+ "to restore device settings\n");
|
|
|
|
|
+ goto error_ret;
|
|
|
|
|
+ }
|
|
|
|
|
+ }
|
|
|
|
|
+ ret = -EAGAIN;
|
|
|
|
|
+ goto error_ret;
|
|
|
|
|
+ }
|
|
|
|
|
+
|
|
|
|
|
+ data->val_status = status;
|
|
|
|
|
+ data->status_valid = true;
|
|
|
|
|
+ data->last_status = jiffies;
|
|
|
|
|
+ }
|
|
|
|
|
+error_ret:
|
|
|
|
|
+ mutex_unlock(&data->read_lock);
|
|
|
|
|
+
|
|
|
|
|
+ return ret;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
/**
|
|
/**
|
|
|
- * sht15_update_single_val() - get a new value from device
|
|
|
|
|
|
|
+ * sht15_measurement() - get a new value from device
|
|
|
* @data: device instance specific data
|
|
* @data: device instance specific data
|
|
|
* @command: command sent to request value
|
|
* @command: command sent to request value
|
|
|
* @timeout_msecs: timeout after which comms are assumed
|
|
* @timeout_msecs: timeout after which comms are assumed
|
|
|
* to have failed are reset.
|
|
* to have failed are reset.
|
|
|
- **/
|
|
|
|
|
-static inline int sht15_update_single_val(struct sht15_data *data,
|
|
|
|
|
- int command,
|
|
|
|
|
- int timeout_msecs)
|
|
|
|
|
|
|
+ */
|
|
|
|
|
+static int sht15_measurement(struct sht15_data *data,
|
|
|
|
|
+ int command,
|
|
|
|
|
+ int timeout_msecs)
|
|
|
{
|
|
{
|
|
|
int ret;
|
|
int ret;
|
|
|
|
|
+ u8 previous_config;
|
|
|
|
|
+
|
|
|
ret = sht15_send_cmd(data, command);
|
|
ret = sht15_send_cmd(data, command);
|
|
|
if (ret)
|
|
if (ret)
|
|
|
return ret;
|
|
return ret;
|
|
@@ -256,38 +519,61 @@ static inline int sht15_update_single_val(struct sht15_data *data,
|
|
|
schedule_work(&data->read_work);
|
|
schedule_work(&data->read_work);
|
|
|
}
|
|
}
|
|
|
ret = wait_event_timeout(data->wait_queue,
|
|
ret = wait_event_timeout(data->wait_queue,
|
|
|
- (data->flag == SHT15_READING_NOTHING),
|
|
|
|
|
|
|
+ (data->state == SHT15_READING_NOTHING),
|
|
|
msecs_to_jiffies(timeout_msecs));
|
|
msecs_to_jiffies(timeout_msecs));
|
|
|
if (ret == 0) {/* timeout occurred */
|
|
if (ret == 0) {/* timeout occurred */
|
|
|
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
|
|
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
|
|
|
sht15_connection_reset(data);
|
|
sht15_connection_reset(data);
|
|
|
return -ETIME;
|
|
return -ETIME;
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
|
|
+ /*
|
|
|
|
|
+ * Perform checksum validation on the received data.
|
|
|
|
|
+ * Specification mentions that in case a checksum verification fails,
|
|
|
|
|
+ * a soft reset command must be sent to the device.
|
|
|
|
|
+ */
|
|
|
|
|
+ if (data->checksumming && !data->checksum_ok) {
|
|
|
|
|
+ previous_config = data->val_status & 0x07;
|
|
|
|
|
+ ret = sht15_soft_reset(data);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ return ret;
|
|
|
|
|
+ if (previous_config) {
|
|
|
|
|
+ ret = sht15_send_status(data, previous_config);
|
|
|
|
|
+ if (ret) {
|
|
|
|
|
+ dev_err(data->dev,
|
|
|
|
|
+ "CRC validation failed, unable "
|
|
|
|
|
+ "to restore device settings\n");
|
|
|
|
|
+ return ret;
|
|
|
|
|
+ }
|
|
|
|
|
+ }
|
|
|
|
|
+ return -EAGAIN;
|
|
|
|
|
+ }
|
|
|
|
|
+
|
|
|
return 0;
|
|
return 0;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
/**
|
|
|
- * sht15_update_vals() - get updated readings from device if too old
|
|
|
|
|
|
|
+ * sht15_update_measurements() - get updated measures from device if too old
|
|
|
* @data: device state
|
|
* @data: device state
|
|
|
- **/
|
|
|
|
|
-static int sht15_update_vals(struct sht15_data *data)
|
|
|
|
|
|
|
+ */
|
|
|
|
|
+static int sht15_update_measurements(struct sht15_data *data)
|
|
|
{
|
|
{
|
|
|
int ret = 0;
|
|
int ret = 0;
|
|
|
int timeout = HZ;
|
|
int timeout = HZ;
|
|
|
|
|
|
|
|
mutex_lock(&data->read_lock);
|
|
mutex_lock(&data->read_lock);
|
|
|
- if (time_after(jiffies, data->last_updat + timeout)
|
|
|
|
|
- || !data->valid) {
|
|
|
|
|
- data->flag = SHT15_READING_HUMID;
|
|
|
|
|
- ret = sht15_update_single_val(data, SHT15_MEASURE_RH, 160);
|
|
|
|
|
|
|
+ if (time_after(jiffies, data->last_measurement + timeout)
|
|
|
|
|
+ || !data->measurements_valid) {
|
|
|
|
|
+ data->state = SHT15_READING_HUMID;
|
|
|
|
|
+ ret = sht15_measurement(data, SHT15_MEASURE_RH, 160);
|
|
|
if (ret)
|
|
if (ret)
|
|
|
goto error_ret;
|
|
goto error_ret;
|
|
|
- data->flag = SHT15_READING_TEMP;
|
|
|
|
|
- ret = sht15_update_single_val(data, SHT15_MEASURE_TEMP, 400);
|
|
|
|
|
|
|
+ data->state = SHT15_READING_TEMP;
|
|
|
|
|
+ ret = sht15_measurement(data, SHT15_MEASURE_TEMP, 400);
|
|
|
if (ret)
|
|
if (ret)
|
|
|
goto error_ret;
|
|
goto error_ret;
|
|
|
- data->valid = 1;
|
|
|
|
|
- data->last_updat = jiffies;
|
|
|
|
|
|
|
+ data->measurements_valid = true;
|
|
|
|
|
+ data->last_measurement = jiffies;
|
|
|
}
|
|
}
|
|
|
error_ret:
|
|
error_ret:
|
|
|
mutex_unlock(&data->read_lock);
|
|
mutex_unlock(&data->read_lock);
|
|
@@ -300,10 +586,11 @@ error_ret:
|
|
|
* @data: device state
|
|
* @data: device state
|
|
|
*
|
|
*
|
|
|
* As per section 4.3 of the data sheet.
|
|
* As per section 4.3 of the data sheet.
|
|
|
- **/
|
|
|
|
|
|
|
+ */
|
|
|
static inline int sht15_calc_temp(struct sht15_data *data)
|
|
static inline int sht15_calc_temp(struct sht15_data *data)
|
|
|
{
|
|
{
|
|
|
int d1 = temppoints[0].d1;
|
|
int d1 = temppoints[0].d1;
|
|
|
|
|
+ int d2 = (data->val_status & SHT15_STATUS_LOW_RESOLUTION) ? 40 : 10;
|
|
|
int i;
|
|
int i;
|
|
|
|
|
|
|
|
for (i = ARRAY_SIZE(temppoints) - 1; i > 0; i--)
|
|
for (i = ARRAY_SIZE(temppoints) - 1; i > 0; i--)
|
|
@@ -316,7 +603,7 @@ static inline int sht15_calc_temp(struct sht15_data *data)
|
|
|
break;
|
|
break;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
- return data->val_temp*10 + d1;
|
|
|
|
|
|
|
+ return data->val_temp * d2 + d1;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
/**
|
|
@@ -325,23 +612,102 @@ static inline int sht15_calc_temp(struct sht15_data *data)
|
|
|
*
|
|
*
|
|
|
* This is the temperature compensated version as per section 4.2 of
|
|
* This is the temperature compensated version as per section 4.2 of
|
|
|
* the data sheet.
|
|
* the data sheet.
|
|
|
- **/
|
|
|
|
|
|
|
+ *
|
|
|
|
|
+ * The sensor is assumed to be V3, which is compatible with V4.
|
|
|
|
|
+ * Humidity conversion coefficients are shown in table 7 of the datasheet.
|
|
|
|
|
+ */
|
|
|
static inline int sht15_calc_humid(struct sht15_data *data)
|
|
static inline int sht15_calc_humid(struct sht15_data *data)
|
|
|
{
|
|
{
|
|
|
- int RHlinear; /* milli percent */
|
|
|
|
|
|
|
+ int rh_linear; /* milli percent */
|
|
|
int temp = sht15_calc_temp(data);
|
|
int temp = sht15_calc_temp(data);
|
|
|
-
|
|
|
|
|
|
|
+ int c2, c3;
|
|
|
|
|
+ int t2;
|
|
|
const int c1 = -4;
|
|
const int c1 = -4;
|
|
|
- const int c2 = 40500; /* x 10 ^ -6 */
|
|
|
|
|
- const int c3 = -28; /* x 10 ^ -7 */
|
|
|
|
|
|
|
|
|
|
- RHlinear = c1*1000
|
|
|
|
|
- + c2 * data->val_humid/1000
|
|
|
|
|
|
|
+ if (data->val_status & SHT15_STATUS_LOW_RESOLUTION) {
|
|
|
|
|
+ c2 = 648000; /* x 10 ^ -6 */
|
|
|
|
|
+ c3 = -7200; /* x 10 ^ -7 */
|
|
|
|
|
+ t2 = 1280;
|
|
|
|
|
+ } else {
|
|
|
|
|
+ c2 = 40500; /* x 10 ^ -6 */
|
|
|
|
|
+ c3 = -28; /* x 10 ^ -7 */
|
|
|
|
|
+ t2 = 80;
|
|
|
|
|
+ }
|
|
|
|
|
+
|
|
|
|
|
+ rh_linear = c1 * 1000
|
|
|
|
|
+ + c2 * data->val_humid / 1000
|
|
|
+ (data->val_humid * data->val_humid * c3) / 10000;
|
|
+ (data->val_humid * data->val_humid * c3) / 10000;
|
|
|
- return (temp - 25000) * (10000 + 80 * data->val_humid)
|
|
|
|
|
- / 1000000 + RHlinear;
|
|
|
|
|
|
|
+ return (temp - 25000) * (10000 + t2 * data->val_humid)
|
|
|
|
|
+ / 1000000 + rh_linear;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_show_status() - show status information in sysfs
|
|
|
|
|
+ * @dev: device.
|
|
|
|
|
+ * @attr: device attribute.
|
|
|
|
|
+ * @buf: sysfs buffer where information is written to.
|
|
|
|
|
+ *
|
|
|
|
|
+ * Will be called on read access to temp1_fault, humidity1_fault
|
|
|
|
|
+ * and heater_enable sysfs attributes.
|
|
|
|
|
+ * Returns number of bytes written into buffer, negative errno on error.
|
|
|
|
|
+ */
|
|
|
|
|
+static ssize_t sht15_show_status(struct device *dev,
|
|
|
|
|
+ struct device_attribute *attr,
|
|
|
|
|
+ char *buf)
|
|
|
|
|
+{
|
|
|
|
|
+ int ret;
|
|
|
|
|
+ struct sht15_data *data = dev_get_drvdata(dev);
|
|
|
|
|
+ u8 bit = to_sensor_dev_attr(attr)->index;
|
|
|
|
|
+
|
|
|
|
|
+ ret = sht15_update_status(data);
|
|
|
|
|
+
|
|
|
|
|
+ return ret ? ret : sprintf(buf, "%d\n", !!(data->val_status & bit));
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_store_heater() - change heater state via sysfs
|
|
|
|
|
+ * @dev: device.
|
|
|
|
|
+ * @attr: device attribute.
|
|
|
|
|
+ * @buf: sysfs buffer to read the new heater state from.
|
|
|
|
|
+ * @count: length of the data.
|
|
|
|
|
+ *
|
|
|
|
|
+ * Will be called on read access to heater_enable sysfs attribute.
|
|
|
|
|
+ * Returns number of bytes actually decoded, negative errno on error.
|
|
|
|
|
+ */
|
|
|
|
|
+static ssize_t sht15_store_heater(struct device *dev,
|
|
|
|
|
+ struct device_attribute *attr,
|
|
|
|
|
+ const char *buf, size_t count)
|
|
|
|
|
+{
|
|
|
|
|
+ int ret;
|
|
|
|
|
+ struct sht15_data *data = dev_get_drvdata(dev);
|
|
|
|
|
+ long value;
|
|
|
|
|
+ u8 status;
|
|
|
|
|
+
|
|
|
|
|
+ if (strict_strtol(buf, 10, &value))
|
|
|
|
|
+ return -EINVAL;
|
|
|
|
|
+
|
|
|
|
|
+ mutex_lock(&data->read_lock);
|
|
|
|
|
+ status = data->val_status & 0x07;
|
|
|
|
|
+ if (!!value)
|
|
|
|
|
+ status |= SHT15_STATUS_HEATER;
|
|
|
|
|
+ else
|
|
|
|
|
+ status &= ~SHT15_STATUS_HEATER;
|
|
|
|
|
+
|
|
|
|
|
+ ret = sht15_send_status(data, status);
|
|
|
|
|
+ mutex_unlock(&data->read_lock);
|
|
|
|
|
+
|
|
|
|
|
+ return ret ? ret : count;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_show_temp() - show temperature measurement value in sysfs
|
|
|
|
|
+ * @dev: device.
|
|
|
|
|
+ * @attr: device attribute.
|
|
|
|
|
+ * @buf: sysfs buffer where measurement values are written to.
|
|
|
|
|
+ *
|
|
|
|
|
+ * Will be called on read access to temp1_input sysfs attribute.
|
|
|
|
|
+ * Returns number of bytes written into buffer, negative errno on error.
|
|
|
|
|
+ */
|
|
|
static ssize_t sht15_show_temp(struct device *dev,
|
|
static ssize_t sht15_show_temp(struct device *dev,
|
|
|
struct device_attribute *attr,
|
|
struct device_attribute *attr,
|
|
|
char *buf)
|
|
char *buf)
|
|
@@ -350,12 +716,21 @@ static ssize_t sht15_show_temp(struct device *dev,
|
|
|
struct sht15_data *data = dev_get_drvdata(dev);
|
|
struct sht15_data *data = dev_get_drvdata(dev);
|
|
|
|
|
|
|
|
/* Technically no need to read humidity as well */
|
|
/* Technically no need to read humidity as well */
|
|
|
- ret = sht15_update_vals(data);
|
|
|
|
|
|
|
+ ret = sht15_update_measurements(data);
|
|
|
|
|
|
|
|
return ret ? ret : sprintf(buf, "%d\n",
|
|
return ret ? ret : sprintf(buf, "%d\n",
|
|
|
sht15_calc_temp(data));
|
|
sht15_calc_temp(data));
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
+/**
|
|
|
|
|
+ * sht15_show_humidity() - show humidity measurement value in sysfs
|
|
|
|
|
+ * @dev: device.
|
|
|
|
|
+ * @attr: device attribute.
|
|
|
|
|
+ * @buf: sysfs buffer where measurement values are written to.
|
|
|
|
|
+ *
|
|
|
|
|
+ * Will be called on read access to humidity1_input sysfs attribute.
|
|
|
|
|
+ * Returns number of bytes written into buffer, negative errno on error.
|
|
|
|
|
+ */
|
|
|
static ssize_t sht15_show_humidity(struct device *dev,
|
|
static ssize_t sht15_show_humidity(struct device *dev,
|
|
|
struct device_attribute *attr,
|
|
struct device_attribute *attr,
|
|
|
char *buf)
|
|
char *buf)
|
|
@@ -363,11 +738,11 @@ static ssize_t sht15_show_humidity(struct device *dev,
|
|
|
int ret;
|
|
int ret;
|
|
|
struct sht15_data *data = dev_get_drvdata(dev);
|
|
struct sht15_data *data = dev_get_drvdata(dev);
|
|
|
|
|
|
|
|
- ret = sht15_update_vals(data);
|
|
|
|
|
|
|
+ ret = sht15_update_measurements(data);
|
|
|
|
|
|
|
|
return ret ? ret : sprintf(buf, "%d\n", sht15_calc_humid(data));
|
|
return ret ? ret : sprintf(buf, "%d\n", sht15_calc_humid(data));
|
|
|
|
|
+}
|
|
|
|
|
|
|
|
-};
|
|
|
|
|
static ssize_t show_name(struct device *dev,
|
|
static ssize_t show_name(struct device *dev,
|
|
|
struct device_attribute *attr,
|
|
struct device_attribute *attr,
|
|
|
char *buf)
|
|
char *buf)
|
|
@@ -376,16 +751,23 @@ static ssize_t show_name(struct device *dev,
|
|
|
return sprintf(buf, "%s\n", pdev->name);
|
|
return sprintf(buf, "%s\n", pdev->name);
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
-static SENSOR_DEVICE_ATTR(temp1_input,
|
|
|
|
|
- S_IRUGO, sht15_show_temp,
|
|
|
|
|
- NULL, 0);
|
|
|
|
|
-static SENSOR_DEVICE_ATTR(humidity1_input,
|
|
|
|
|
- S_IRUGO, sht15_show_humidity,
|
|
|
|
|
- NULL, 0);
|
|
|
|
|
|
|
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
|
|
|
|
|
+ sht15_show_temp, NULL, 0);
|
|
|
|
|
+static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO,
|
|
|
|
|
+ sht15_show_humidity, NULL, 0);
|
|
|
|
|
+static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, sht15_show_status, NULL,
|
|
|
|
|
+ SHT15_STATUS_LOW_BATTERY);
|
|
|
|
|
+static SENSOR_DEVICE_ATTR(humidity1_fault, S_IRUGO, sht15_show_status, NULL,
|
|
|
|
|
+ SHT15_STATUS_LOW_BATTERY);
|
|
|
|
|
+static SENSOR_DEVICE_ATTR(heater_enable, S_IRUGO | S_IWUSR, sht15_show_status,
|
|
|
|
|
+ sht15_store_heater, SHT15_STATUS_HEATER);
|
|
|
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
|
|
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
|
|
|
static struct attribute *sht15_attrs[] = {
|
|
static struct attribute *sht15_attrs[] = {
|
|
|
&sensor_dev_attr_temp1_input.dev_attr.attr,
|
|
&sensor_dev_attr_temp1_input.dev_attr.attr,
|
|
|
&sensor_dev_attr_humidity1_input.dev_attr.attr,
|
|
&sensor_dev_attr_humidity1_input.dev_attr.attr,
|
|
|
|
|
+ &sensor_dev_attr_temp1_fault.dev_attr.attr,
|
|
|
|
|
+ &sensor_dev_attr_humidity1_fault.dev_attr.attr,
|
|
|
|
|
+ &sensor_dev_attr_heater_enable.dev_attr.attr,
|
|
|
&dev_attr_name.attr,
|
|
&dev_attr_name.attr,
|
|
|
NULL,
|
|
NULL,
|
|
|
};
|
|
};
|
|
@@ -397,59 +779,31 @@ static const struct attribute_group sht15_attr_group = {
|
|
|
static irqreturn_t sht15_interrupt_fired(int irq, void *d)
|
|
static irqreturn_t sht15_interrupt_fired(int irq, void *d)
|
|
|
{
|
|
{
|
|
|
struct sht15_data *data = d;
|
|
struct sht15_data *data = d;
|
|
|
|
|
+
|
|
|
/* First disable the interrupt */
|
|
/* First disable the interrupt */
|
|
|
disable_irq_nosync(irq);
|
|
disable_irq_nosync(irq);
|
|
|
atomic_inc(&data->interrupt_handled);
|
|
atomic_inc(&data->interrupt_handled);
|
|
|
/* Then schedule a reading work struct */
|
|
/* Then schedule a reading work struct */
|
|
|
- if (data->flag != SHT15_READING_NOTHING)
|
|
|
|
|
|
|
+ if (data->state != SHT15_READING_NOTHING)
|
|
|
schedule_work(&data->read_work);
|
|
schedule_work(&data->read_work);
|
|
|
return IRQ_HANDLED;
|
|
return IRQ_HANDLED;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
-/* Each byte of data is acknowledged by pulling the data line
|
|
|
|
|
- * low for one clock pulse.
|
|
|
|
|
- */
|
|
|
|
|
-static void sht15_ack(struct sht15_data *data)
|
|
|
|
|
-{
|
|
|
|
|
- gpio_direction_output(data->pdata->gpio_data, 0);
|
|
|
|
|
- ndelay(SHT15_TSU);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
- ndelay(SHT15_TSU);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
- ndelay(SHT15_TSU);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_data, 1);
|
|
|
|
|
-
|
|
|
|
|
- gpio_direction_input(data->pdata->gpio_data);
|
|
|
|
|
-}
|
|
|
|
|
-/**
|
|
|
|
|
- * sht15_end_transmission() - notify device of end of transmission
|
|
|
|
|
- * @data: device state
|
|
|
|
|
- *
|
|
|
|
|
- * This is basically a NAK. (single clock pulse, data high)
|
|
|
|
|
- **/
|
|
|
|
|
-static void sht15_end_transmission(struct sht15_data *data)
|
|
|
|
|
-{
|
|
|
|
|
- gpio_direction_output(data->pdata->gpio_data, 1);
|
|
|
|
|
- ndelay(SHT15_TSU);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
- ndelay(SHT15_TSCKH);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
- ndelay(SHT15_TSCKL);
|
|
|
|
|
-}
|
|
|
|
|
-
|
|
|
|
|
static void sht15_bh_read_data(struct work_struct *work_s)
|
|
static void sht15_bh_read_data(struct work_struct *work_s)
|
|
|
{
|
|
{
|
|
|
- int i;
|
|
|
|
|
uint16_t val = 0;
|
|
uint16_t val = 0;
|
|
|
|
|
+ u8 dev_checksum = 0;
|
|
|
|
|
+ u8 checksum_vals[3];
|
|
|
struct sht15_data *data
|
|
struct sht15_data *data
|
|
|
= container_of(work_s, struct sht15_data,
|
|
= container_of(work_s, struct sht15_data,
|
|
|
read_work);
|
|
read_work);
|
|
|
|
|
+
|
|
|
/* Firstly, verify the line is low */
|
|
/* Firstly, verify the line is low */
|
|
|
if (gpio_get_value(data->pdata->gpio_data)) {
|
|
if (gpio_get_value(data->pdata->gpio_data)) {
|
|
|
- /* If not, then start the interrupt again - care
|
|
|
|
|
- here as could have gone low in meantime so verify
|
|
|
|
|
- it hasn't!
|
|
|
|
|
- */
|
|
|
|
|
|
|
+ /*
|
|
|
|
|
+ * If not, then start the interrupt again - care here as could
|
|
|
|
|
+ * have gone low in meantime so verify it hasn't!
|
|
|
|
|
+ */
|
|
|
atomic_set(&data->interrupt_handled, 0);
|
|
atomic_set(&data->interrupt_handled, 0);
|
|
|
enable_irq(gpio_to_irq(data->pdata->gpio_data));
|
|
enable_irq(gpio_to_irq(data->pdata->gpio_data));
|
|
|
/* If still not occurred or another handler has been scheduled */
|
|
/* If still not occurred or another handler has been scheduled */
|
|
@@ -457,30 +811,43 @@ static void sht15_bh_read_data(struct work_struct *work_s)
|
|
|
|| atomic_read(&data->interrupt_handled))
|
|
|| atomic_read(&data->interrupt_handled))
|
|
|
return;
|
|
return;
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
/* Read the data back from the device */
|
|
/* Read the data back from the device */
|
|
|
- for (i = 0; i < 16; ++i) {
|
|
|
|
|
- val <<= 1;
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 1);
|
|
|
|
|
- ndelay(SHT15_TSCKH);
|
|
|
|
|
- val |= !!gpio_get_value(data->pdata->gpio_data);
|
|
|
|
|
- gpio_set_value(data->pdata->gpio_sck, 0);
|
|
|
|
|
- ndelay(SHT15_TSCKL);
|
|
|
|
|
- if (i == 7)
|
|
|
|
|
- sht15_ack(data);
|
|
|
|
|
|
|
+ val = sht15_read_byte(data);
|
|
|
|
|
+ val <<= 8;
|
|
|
|
|
+ sht15_ack(data);
|
|
|
|
|
+ val |= sht15_read_byte(data);
|
|
|
|
|
+
|
|
|
|
|
+ if (data->checksumming) {
|
|
|
|
|
+ /*
|
|
|
|
|
+ * Ask the device for a checksum and read it back.
|
|
|
|
|
+ * Note: the device sends the checksum byte reversed.
|
|
|
|
|
+ */
|
|
|
|
|
+ sht15_ack(data);
|
|
|
|
|
+ dev_checksum = sht15_reverse(sht15_read_byte(data));
|
|
|
|
|
+ checksum_vals[0] = (data->state == SHT15_READING_TEMP) ?
|
|
|
|
|
+ SHT15_MEASURE_TEMP : SHT15_MEASURE_RH;
|
|
|
|
|
+ checksum_vals[1] = (u8) (val >> 8);
|
|
|
|
|
+ checksum_vals[2] = (u8) val;
|
|
|
|
|
+ data->checksum_ok
|
|
|
|
|
+ = (sht15_crc8(data, checksum_vals, 3) == dev_checksum);
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
/* Tell the device we are done */
|
|
/* Tell the device we are done */
|
|
|
sht15_end_transmission(data);
|
|
sht15_end_transmission(data);
|
|
|
|
|
|
|
|
- switch (data->flag) {
|
|
|
|
|
|
|
+ switch (data->state) {
|
|
|
case SHT15_READING_TEMP:
|
|
case SHT15_READING_TEMP:
|
|
|
data->val_temp = val;
|
|
data->val_temp = val;
|
|
|
break;
|
|
break;
|
|
|
case SHT15_READING_HUMID:
|
|
case SHT15_READING_HUMID:
|
|
|
data->val_humid = val;
|
|
data->val_humid = val;
|
|
|
break;
|
|
break;
|
|
|
|
|
+ default:
|
|
|
|
|
+ break;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
- data->flag = SHT15_READING_NOTHING;
|
|
|
|
|
|
|
+ data->state = SHT15_READING_NOTHING;
|
|
|
wake_up(&data->wait_queue);
|
|
wake_up(&data->wait_queue);
|
|
|
}
|
|
}
|
|
|
|
|
|
|
@@ -500,10 +867,10 @@ static void sht15_update_voltage(struct work_struct *work_s)
|
|
|
*
|
|
*
|
|
|
* Note that as the notification code holds the regulator lock, we have
|
|
* Note that as the notification code holds the regulator lock, we have
|
|
|
* to schedule an update of the supply voltage rather than getting it directly.
|
|
* to schedule an update of the supply voltage rather than getting it directly.
|
|
|
- **/
|
|
|
|
|
|
|
+ */
|
|
|
static int sht15_invalidate_voltage(struct notifier_block *nb,
|
|
static int sht15_invalidate_voltage(struct notifier_block *nb,
|
|
|
- unsigned long event,
|
|
|
|
|
- void *ignored)
|
|
|
|
|
|
|
+ unsigned long event,
|
|
|
|
|
+ void *ignored)
|
|
|
{
|
|
{
|
|
|
struct sht15_data *data = container_of(nb, struct sht15_data, nb);
|
|
struct sht15_data *data = container_of(nb, struct sht15_data, nb);
|
|
|
|
|
|
|
@@ -518,10 +885,11 @@ static int __devinit sht15_probe(struct platform_device *pdev)
|
|
|
{
|
|
{
|
|
|
int ret = 0;
|
|
int ret = 0;
|
|
|
struct sht15_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
|
|
struct sht15_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
|
|
|
|
|
+ u8 status = 0;
|
|
|
|
|
|
|
|
if (!data) {
|
|
if (!data) {
|
|
|
ret = -ENOMEM;
|
|
ret = -ENOMEM;
|
|
|
- dev_err(&pdev->dev, "kzalloc failed");
|
|
|
|
|
|
|
+ dev_err(&pdev->dev, "kzalloc failed\n");
|
|
|
goto error_ret;
|
|
goto error_ret;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
@@ -533,13 +901,22 @@ static int __devinit sht15_probe(struct platform_device *pdev)
|
|
|
init_waitqueue_head(&data->wait_queue);
|
|
init_waitqueue_head(&data->wait_queue);
|
|
|
|
|
|
|
|
if (pdev->dev.platform_data == NULL) {
|
|
if (pdev->dev.platform_data == NULL) {
|
|
|
- dev_err(&pdev->dev, "no platform data supplied");
|
|
|
|
|
|
|
+ dev_err(&pdev->dev, "no platform data supplied\n");
|
|
|
goto err_free_data;
|
|
goto err_free_data;
|
|
|
}
|
|
}
|
|
|
data->pdata = pdev->dev.platform_data;
|
|
data->pdata = pdev->dev.platform_data;
|
|
|
- data->supply_uV = data->pdata->supply_mv*1000;
|
|
|
|
|
-
|
|
|
|
|
-/* If a regulator is available, query what the supply voltage actually is!*/
|
|
|
|
|
|
|
+ data->supply_uV = data->pdata->supply_mv * 1000;
|
|
|
|
|
+ if (data->pdata->checksum)
|
|
|
|
|
+ data->checksumming = true;
|
|
|
|
|
+ if (data->pdata->no_otp_reload)
|
|
|
|
|
+ status |= SHT15_STATUS_NO_OTP_RELOAD;
|
|
|
|
|
+ if (data->pdata->low_resolution)
|
|
|
|
|
+ status |= SHT15_STATUS_LOW_RESOLUTION;
|
|
|
|
|
+
|
|
|
|
|
+ /*
|
|
|
|
|
+ * If a regulator is available,
|
|
|
|
|
+ * query what the supply voltage actually is!
|
|
|
|
|
+ */
|
|
|
data->reg = regulator_get(data->dev, "vcc");
|
|
data->reg = regulator_get(data->dev, "vcc");
|
|
|
if (!IS_ERR(data->reg)) {
|
|
if (!IS_ERR(data->reg)) {
|
|
|
int voltage;
|
|
int voltage;
|
|
@@ -549,28 +926,34 @@ static int __devinit sht15_probe(struct platform_device *pdev)
|
|
|
data->supply_uV = voltage;
|
|
data->supply_uV = voltage;
|
|
|
|
|
|
|
|
regulator_enable(data->reg);
|
|
regulator_enable(data->reg);
|
|
|
- /* setup a notifier block to update this if another device
|
|
|
|
|
- * causes the voltage to change */
|
|
|
|
|
|
|
+ /*
|
|
|
|
|
+ * Setup a notifier block to update this if another device
|
|
|
|
|
+ * causes the voltage to change
|
|
|
|
|
+ */
|
|
|
data->nb.notifier_call = &sht15_invalidate_voltage;
|
|
data->nb.notifier_call = &sht15_invalidate_voltage;
|
|
|
ret = regulator_register_notifier(data->reg, &data->nb);
|
|
ret = regulator_register_notifier(data->reg, &data->nb);
|
|
|
|
|
+ if (ret) {
|
|
|
|
|
+ dev_err(&pdev->dev,
|
|
|
|
|
+ "regulator notifier request failed\n");
|
|
|
|
|
+ regulator_disable(data->reg);
|
|
|
|
|
+ regulator_put(data->reg);
|
|
|
|
|
+ goto err_free_data;
|
|
|
|
|
+ }
|
|
|
}
|
|
}
|
|
|
-/* Try requesting the GPIOs */
|
|
|
|
|
|
|
+
|
|
|
|
|
+ /* Try requesting the GPIOs */
|
|
|
ret = gpio_request(data->pdata->gpio_sck, "SHT15 sck");
|
|
ret = gpio_request(data->pdata->gpio_sck, "SHT15 sck");
|
|
|
if (ret) {
|
|
if (ret) {
|
|
|
- dev_err(&pdev->dev, "gpio request failed");
|
|
|
|
|
- goto err_free_data;
|
|
|
|
|
|
|
+ dev_err(&pdev->dev, "gpio request failed\n");
|
|
|
|
|
+ goto err_release_reg;
|
|
|
}
|
|
}
|
|
|
gpio_direction_output(data->pdata->gpio_sck, 0);
|
|
gpio_direction_output(data->pdata->gpio_sck, 0);
|
|
|
|
|
+
|
|
|
ret = gpio_request(data->pdata->gpio_data, "SHT15 data");
|
|
ret = gpio_request(data->pdata->gpio_data, "SHT15 data");
|
|
|
if (ret) {
|
|
if (ret) {
|
|
|
- dev_err(&pdev->dev, "gpio request failed");
|
|
|
|
|
|
|
+ dev_err(&pdev->dev, "gpio request failed\n");
|
|
|
goto err_release_gpio_sck;
|
|
goto err_release_gpio_sck;
|
|
|
}
|
|
}
|
|
|
- ret = sysfs_create_group(&pdev->dev.kobj, &sht15_attr_group);
|
|
|
|
|
- if (ret) {
|
|
|
|
|
- dev_err(&pdev->dev, "sysfs create failed");
|
|
|
|
|
- goto err_release_gpio_data;
|
|
|
|
|
- }
|
|
|
|
|
|
|
|
|
|
ret = request_irq(gpio_to_irq(data->pdata->gpio_data),
|
|
ret = request_irq(gpio_to_irq(data->pdata->gpio_data),
|
|
|
sht15_interrupt_fired,
|
|
sht15_interrupt_fired,
|
|
@@ -578,30 +961,53 @@ static int __devinit sht15_probe(struct platform_device *pdev)
|
|
|
"sht15 data",
|
|
"sht15 data",
|
|
|
data);
|
|
data);
|
|
|
if (ret) {
|
|
if (ret) {
|
|
|
- dev_err(&pdev->dev, "failed to get irq for data line");
|
|
|
|
|
|
|
+ dev_err(&pdev->dev, "failed to get irq for data line\n");
|
|
|
goto err_release_gpio_data;
|
|
goto err_release_gpio_data;
|
|
|
}
|
|
}
|
|
|
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
|
|
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
|
|
|
sht15_connection_reset(data);
|
|
sht15_connection_reset(data);
|
|
|
- sht15_send_cmd(data, 0x1E);
|
|
|
|
|
|
|
+ ret = sht15_soft_reset(data);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ goto err_release_irq;
|
|
|
|
|
+
|
|
|
|
|
+ /* write status with platform data options */
|
|
|
|
|
+ if (status) {
|
|
|
|
|
+ ret = sht15_send_status(data, status);
|
|
|
|
|
+ if (ret)
|
|
|
|
|
+ goto err_release_irq;
|
|
|
|
|
+ }
|
|
|
|
|
+
|
|
|
|
|
+ ret = sysfs_create_group(&pdev->dev.kobj, &sht15_attr_group);
|
|
|
|
|
+ if (ret) {
|
|
|
|
|
+ dev_err(&pdev->dev, "sysfs create failed\n");
|
|
|
|
|
+ goto err_release_irq;
|
|
|
|
|
+ }
|
|
|
|
|
|
|
|
data->hwmon_dev = hwmon_device_register(data->dev);
|
|
data->hwmon_dev = hwmon_device_register(data->dev);
|
|
|
if (IS_ERR(data->hwmon_dev)) {
|
|
if (IS_ERR(data->hwmon_dev)) {
|
|
|
ret = PTR_ERR(data->hwmon_dev);
|
|
ret = PTR_ERR(data->hwmon_dev);
|
|
|
- goto err_release_irq;
|
|
|
|
|
|
|
+ goto err_release_sysfs_group;
|
|
|
}
|
|
}
|
|
|
|
|
+
|
|
|
return 0;
|
|
return 0;
|
|
|
|
|
|
|
|
|
|
+err_release_sysfs_group:
|
|
|
|
|
+ sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
|
|
|
err_release_irq:
|
|
err_release_irq:
|
|
|
free_irq(gpio_to_irq(data->pdata->gpio_data), data);
|
|
free_irq(gpio_to_irq(data->pdata->gpio_data), data);
|
|
|
err_release_gpio_data:
|
|
err_release_gpio_data:
|
|
|
gpio_free(data->pdata->gpio_data);
|
|
gpio_free(data->pdata->gpio_data);
|
|
|
err_release_gpio_sck:
|
|
err_release_gpio_sck:
|
|
|
gpio_free(data->pdata->gpio_sck);
|
|
gpio_free(data->pdata->gpio_sck);
|
|
|
|
|
+err_release_reg:
|
|
|
|
|
+ if (!IS_ERR(data->reg)) {
|
|
|
|
|
+ regulator_unregister_notifier(data->reg, &data->nb);
|
|
|
|
|
+ regulator_disable(data->reg);
|
|
|
|
|
+ regulator_put(data->reg);
|
|
|
|
|
+ }
|
|
|
err_free_data:
|
|
err_free_data:
|
|
|
kfree(data);
|
|
kfree(data);
|
|
|
error_ret:
|
|
error_ret:
|
|
|
-
|
|
|
|
|
return ret;
|
|
return ret;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
@@ -609,9 +1015,15 @@ static int __devexit sht15_remove(struct platform_device *pdev)
|
|
|
{
|
|
{
|
|
|
struct sht15_data *data = platform_get_drvdata(pdev);
|
|
struct sht15_data *data = platform_get_drvdata(pdev);
|
|
|
|
|
|
|
|
- /* Make sure any reads from the device are done and
|
|
|
|
|
- * prevent new ones from beginning */
|
|
|
|
|
|
|
+ /*
|
|
|
|
|
+ * Make sure any reads from the device are done and
|
|
|
|
|
+ * prevent new ones beginning
|
|
|
|
|
+ */
|
|
|
mutex_lock(&data->read_lock);
|
|
mutex_lock(&data->read_lock);
|
|
|
|
|
+ if (sht15_soft_reset(data)) {
|
|
|
|
|
+ mutex_unlock(&data->read_lock);
|
|
|
|
|
+ return -EFAULT;
|
|
|
|
|
+ }
|
|
|
hwmon_device_unregister(data->hwmon_dev);
|
|
hwmon_device_unregister(data->hwmon_dev);
|
|
|
sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
|
|
sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
|
|
|
if (!IS_ERR(data->reg)) {
|
|
if (!IS_ERR(data->reg)) {
|
|
@@ -625,10 +1037,10 @@ static int __devexit sht15_remove(struct platform_device *pdev)
|
|
|
gpio_free(data->pdata->gpio_sck);
|
|
gpio_free(data->pdata->gpio_sck);
|
|
|
mutex_unlock(&data->read_lock);
|
|
mutex_unlock(&data->read_lock);
|
|
|
kfree(data);
|
|
kfree(data);
|
|
|
|
|
+
|
|
|
return 0;
|
|
return 0;
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
-
|
|
|
|
|
/*
|
|
/*
|
|
|
* sht_drivers simultaneously refers to __devinit and __devexit function
|
|
* sht_drivers simultaneously refers to __devinit and __devexit function
|
|
|
* which causes spurious section mismatch warning. So use __refdata to
|
|
* which causes spurious section mismatch warning. So use __refdata to
|
|
@@ -673,7 +1085,6 @@ static struct platform_driver __refdata sht_drivers[] = {
|
|
|
},
|
|
},
|
|
|
};
|
|
};
|
|
|
|
|
|
|
|
-
|
|
|
|
|
static int __init sht15_init(void)
|
|
static int __init sht15_init(void)
|
|
|
{
|
|
{
|
|
|
int ret;
|
|
int ret;
|