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hwmon: (sht3x) remove blocking_io property

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Due to no support on clock-strench, blocking mode was removed and
now single-shot mode only uses non-blocking mode.

Signed-off-by: JuenKit Yip <JuenKit_Yip@hotmail.com>
Link: https://lore.kernel.org/r/DB4PR10MB6261DA9202AF37B4F6ECDD6C9258A@DB4PR10MB6261.EURPRD10.PROD.OUTLOOK.COM
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
JuenKit Yip 2023-06-17 00:00:13 +08:00 committed by Guenter Roeck
parent fc669e922e
commit 5bca68ac63
2 changed files with 16 additions and 29 deletions
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12
Documentation/hwmon/sht3x.rst
View file

@ -28,16 +28,14 @@ The device communicates with the I2C protocol. Sensors can have the I2C
addresses 0x44 or 0x45, depending on the wiring. See
Documentation/i2c/instantiating-devices.rst for methods to instantiate the device.
There are two options configurable by means of sht3x_data:
There is only one option configurable by means of sht3x_data:
1. blocking (pull the I2C clock line down while performing the measurement) or
non-blocking mode. Blocking mode will guarantee the fastest result but
the I2C bus will be busy during that time. By default, non-blocking mode
is used. Make sure clock-stretching works properly on your device if you
want to use blocking mode.
2. high or low accuracy. High accuracy is used by default and using it is
high or low accuracy. High accuracy is used by default and using it is
strongly recommended.
Even if sht3x sensor supports clock-strech(blocking mode) and non-strench
(non-blocking mode) in single-shot mode, this driver only supports the latter.
The sht3x sensor supports a single shot mode as well as 5 periodic measure
modes, which can be controlled with the update_interval sysfs interface.
The allowed update_interval in milliseconds are as follows:

33
drivers/hwmon/sht3x.c
View file

@ -22,12 +22,10 @@
#include <linux/jiffies.h>
/* commands (high precision mode) */
static const unsigned char sht3x_cmd_measure_blocking_hpm[] = { 0x2c, 0x06 };
static const unsigned char sht3x_cmd_measure_nonblocking_hpm[] = { 0x24, 0x00 };
static const unsigned char sht3x_cmd_measure_single_hpm[] = { 0x24, 0x00 };
/* commands (low power mode) */
static const unsigned char sht3x_cmd_measure_blocking_lpm[] = { 0x2c, 0x10 };
static const unsigned char sht3x_cmd_measure_nonblocking_lpm[] = { 0x24, 0x16 };
static const unsigned char sht3x_cmd_measure_single_lpm[] = { 0x24, 0x16 };
/* commands for periodic mode */
static const unsigned char sht3x_cmd_measure_periodic_mode[] = { 0xe0, 0x00 };
@ -41,9 +39,9 @@ static const unsigned char sht3x_cmd_heater_off[] = { 0x30, 0x66 };
static const unsigned char sht3x_cmd_read_status_reg[] = { 0xf3, 0x2d };
static const unsigned char sht3x_cmd_clear_status_reg[] = { 0x30, 0x41 };
/* delays for non-blocking i2c commands, both in us */
#define SHT3X_NONBLOCKING_WAIT_TIME_HPM 15000
#define SHT3X_NONBLOCKING_WAIT_TIME_LPM 4000
/* delays for single-shot mode i2c commands, both in us */
#define SHT3X_SINGLE_WAIT_TIME_HPM 15000
#define SHT3X_SINGLE_WAIT_TIME_LPM 4000
#define SHT3X_WORD_LEN 2
#define SHT3X_CMD_LENGTH 2
@ -134,7 +132,6 @@ struct sht3x_data {
const unsigned char *command;
u32 wait_time; /* in us*/
unsigned long last_update; /* last update in periodic mode*/
bool blocking_io;
bool high_precision;
/*
@ -432,26 +429,19 @@ static ssize_t humidity1_limit_store(struct device *dev,
static void sht3x_select_command(struct sht3x_data *data)
{
/*
* In blocking mode (clock stretching mode) the I2C bus
* is blocked for other traffic, thus the call to i2c_master_recv()
* will wait until the data is ready. For non blocking mode, we
* have to wait ourselves.
* For single-shot mode, only non blocking mode is support,
* we have to wait ourselves for result.
*/
if (data->mode > 0) {
data->command = sht3x_cmd_measure_periodic_mode;
data->wait_time = 0;
} else if (data->blocking_io) {
data->command = data->high_precision ?
sht3x_cmd_measure_blocking_hpm :
sht3x_cmd_measure_blocking_lpm;
data->wait_time = 0;
} else {
if (data->high_precision) {
data->command = sht3x_cmd_measure_nonblocking_hpm;
data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_HPM;
data->command = sht3x_cmd_measure_single_hpm;
data->wait_time = SHT3X_SINGLE_WAIT_TIME_HPM;
} else {
data->command = sht3x_cmd_measure_nonblocking_lpm;
data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_LPM;
data->command = sht3x_cmd_measure_single_lpm;
data->wait_time = SHT3X_SINGLE_WAIT_TIME_LPM;
}
}
}
@ -689,7 +679,6 @@ static int sht3x_probe(struct i2c_client *client)
if (!data)
return -ENOMEM;
data->blocking_io = false;
data->high_precision = true;
data->mode = 0;
data->last_update = jiffies - msecs_to_jiffies(3000);