[PATCH] Add STMicroelectronics LPS001WP pressure sensor device driver into misc
From: mems applications
Date: Mon Mar 14 2011 - 13:55:31 EST
---
Documentation/ABI/testing/sysfs-i2c-lps001wp_prs | 64 ++
drivers/misc/Kconfig | 10 +
drivers/misc/Makefile | 1 +
drivers/misc/lps001wp.h | 67 ++
drivers/misc/lps001wp_prs.c | 1137 ++++++++++++++++++++++
5 files changed, 1279 insertions(+), 0 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-i2c-lps001wp_prs
create mode 100644 drivers/misc/lps001wp.h
create mode 100644 drivers/misc/lps001wp_prs.c
diff --git a/Documentation/ABI/testing/sysfs-i2c-lps001wp_prs b/Documentation/ABI/testing/sysfs-i2c-lps001wp_prs
new file mode 100644
index 0000000..55c87c9
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-i2c-lps001wp_prs
@@ -0,0 +1,64 @@
+What: /sys/bus/i2c/devices/<busnum>-<devaddr>/enable_device
+Date: March 2011
+Contact: Matteo Dameno <matteo.dameno@xxxxxx>
+Contact: Carmine Iascone <carmine.iascone@xxxxxx>
+Description: Enables the devices: switches it between Power Down and Normal
+ working modes. Switches the device on or off.
+
+ Reading: returns 0 if Power Down mode is set;
+ returns 1 if Normal mode is set.
+
+ Writing: sets the working mode.
+ Accepted values: 0, 1.
+
+
+What: /sys/bus/i2c/devices/<busnum>-<devaddr>/poll_period_ms
+Date: March 2011
+Contact: Matteo Dameno <matteo.dameno@xxxxxx>
+Contact: Carmine Iascone <carmine.iascone@xxxxxx>
+Description: Shows/Stores the data output polling period experessed in msec.
+ The driver automatically selects to better ODR to support the
+ polling period choise.
+ The data output is diverted to input device.
+ The updated values are polled at a 1/poll_period_ms (KHz)
+ frequency.
+
+ Reading: returns the current polling period (msec).
+ Writing: sets the current polling period to the given integer
+ number of msec.
+ Accepted values: 1,2,3,..,1000,...
+
+
+What: /sys/bus/i2c/devices/<busnum>-<devaddr>/enable_differential_output
+Date: March 2011
+Contact: Matteo Dameno <matteo.dameno@xxxxxx>
+Contact: Carmine Iascone <carmine.iascone@xxxxxx>
+Description: Tells the lps001wp to enable circuitry to calculate
+ differential pressure and start to output it.
+ Differential pressure is calculated as the difference between a
+ constant reference value, stored in pressure_reference_level as
+ described below, and the actual pressure measured.
+
+
+ Reading: returns 0 if differential output is disabled;
+ returns 1 if differential output is enabled.
+
+ Writing: enables the differential output.
+ Accepted values: 0, 1.
+
+
+What: /sys/bus/i2c/devices/<busnum>-<devaddr>/lowpower_enable
+Date: March 2011
+Contact: Matteo Dameno <matteo.dameno@xxxxxx>
+Contact: Carmine Iascone <carmine.iascone@xxxxxx>
+Description: Tells the lps001wp to switch to low power mode.
+ This options let the device to work at a lower power consumption
+ rate. The cost is a decay on output resolution/noise density.
+
+
+ Reading: returns 0 if low power mode is disabled;
+ returns 1 if low power mode is enabled.
+
+ Writing: enables the low power consumtion working mode .
+ Accepted values: 0, 1.
+
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 203500d..c728f10 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -448,6 +448,16 @@ config BMP085
To compile this driver as a module, choose M here: the
module will be called bmp085.
+config LPS001WP_PRS
+ tristate "STMicroelectronics LPS001WP MEMS Pressure Temperature Sensor"
+ depends on I2C
+ default n
+ help
+ If you say yes here you get support for the
+ STM LPS001WP Barometer/Thermometer on I2C bus.
+ This driver can also be built as a module (choose M).
+ If so, the module will be called lps001wp_prs.
+
config PCH_PHUB
tristate "PCH Packet Hub of Intel Topcliff / OKI SEMICONDUCTOR ML7213"
depends on PCI
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 804f421..621f42a 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o
obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o
obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o
obj-$(CONFIG_BMP085) += bmp085.o
+obj-$(CONFIG_LPS001WP_PRS) += lps001wp_prs.o
obj-$(CONFIG_ICS932S401) += ics932s401.o
obj-$(CONFIG_LKDTM) += lkdtm.o
obj-$(CONFIG_TIFM_CORE) += tifm_core.o
diff --git a/drivers/misc/lps001wp.h b/drivers/misc/lps001wp.h
new file mode 100644
index 0000000..52a7bb0
--- /dev/null
+++ b/drivers/misc/lps001wp.h
@@ -0,0 +1,67 @@
+/*
+* STMicroelectronics LPS001WP Pressure / Temperature Sensor module driver
+*
+* Copyright (C) 2010 STMicroelectronics
+* Matteo Dameno (matteo.dameno@xxxxxx)
+* Carmine Iascone (carmine.iascone@xxxxxx)
+*
+* Both authors are willing to be considered the contact and update points for
+* the driver.
+*
+*
+* 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
+*
+*/
+
+#ifndef __LPS001WP_H__
+#define __LPS001WP_H__
+
+#define SAD0L 0x00
+#define SAD0H 0x01
+#define LPS001WP_PRS_I2C_SADROOT 0x2E
+#define LPS001WP_PRS_I2C_SAD_L ((LPS001WP_PRS_I2C_SADROOT<<1)|SAD0L)
+#define LPS001WP_PRS_I2C_SAD_H ((LPS001WP_PRS_I2C_SADROOT<<1)|SAD0H)
+#define LPS001WP_PRS_DEV_NAME "lps001wp_prs"
+
+/* input define mappings */
+#define ABS_PR ABS_PRESSURE
+#define ABS_TEMP ABS_GAS
+#define ABS_DLTPR ABS_MISC
+
+/* Pressure section defines */
+
+/* Pressure Sensor Operating Mode */
+#define LPS001WP_PRS_ENABLE 0x01
+#define LPS001WP_PRS_DISABLE 0x00
+
+#define LPS001WP_PRS_PM_NORMAL 0x40
+#define LPS001WP_PRS_PM_OFF LPS001WP_PRS_DISABLE
+
+#define SENSITIVITY_T 64 /** = 64 LSB/degrC */
+#define SENSITIVITY_P 16 /** = 16 LSB/mbar */
+
+#ifdef __KERNEL__
+struct lps001wp_prs_platform_data {
+ int poll_interval;
+ int min_interval;
+
+ int (*init)(void);
+ void (*exit)(void);
+ int (*power_on)(void);
+ int (*power_off)(void);
+};
+#endif /* __KERNEL__ */
+
+#endif /* __LPS001WP_H__ */
diff --git a/drivers/misc/lps001wp_prs.c b/drivers/misc/lps001wp_prs.c
new file mode 100644
index 0000000..5ed8398
--- /dev/null
+++ b/drivers/misc/lps001wp_prs.c
@@ -0,0 +1,1137 @@
+/*
+* drivers/misc/lps001wp_prs.c
+*
+* STMicroelectronics LPS001WP Pressure / Temperature Sensor module driver
+*
+* Copyright (C) 2010 STMicroelectronics
+* Matteo Dameno (matteo.dameno@xxxxxx)
+* Carmine Iascone (carmine.iascone@xxxxxx)
+*
+* Both authors are willing to be considered the contact and update points for
+* the driver.
+*
+* This driver supports the STMicroelectronics LPS001WP digital pressure and
+* temperature sensor. The datasheet for the device is avaliable from STM
+* website, currently at:
+*
+* http://www.st.com/internet/analog/product/251247.jsp
+*
+* Output data from the device are available from the assigned
+* /dev/input/eventX device;
+*
+* LPS001WP can be controlled by sysfs interface looking inside:
+* /sys/bus/i2c/devices/<busnum>-<devaddr>/
+*
+* LPS001WP make available to i2C addresses selectable from platform_data
+* by the LPS001WP_PRS_I2C_SAD_H or LPS001WP_PRS_I2C_SAD_L.
+*
+* Read pressures and temperatures output can be converted in units of
+* measurement by deviding them for SENSITIVITY_P and SENSITIVITY_T
+* respectively.
+* Obtained values are then expessed as
+* mbar (=0.1 kPa) and Celsius degrees.
+*
+* 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/err.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/i2c.h>
+
+#include <linux/input.h>
+#include <linux/uaccess.h>
+
+#include <linux/workqueue.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+
+#include "lps001wp.h"
+
+
+#define PR_ABS_MAX USHRT_MAX
+
+#define PR_ABS_MIN (u16)(0U)
+#define PR_DLT_MAX SHRT_MAX
+#define PR_DLT_MIN SHRT_MIN
+#define TEMP_MAX SHRT_MAX
+#define TEMP_MIN SHRT_MIN
+
+
+#define SENSITIVITY_T_SHIFT 6 /** = 64 LSB/degrC */
+#define SENSITIVITY_P_SHIFT 4 /** = 16 LSB/mbar */
+
+/* output/reference first registers */
+#define OUTDATA_REG 0x28
+#define INDATA_REG 0X30
+
+#define WHOAMI_LPS001WP_PRS 0xBA /* Expctd content for WAI */
+
+/* CONTROL REGISTERS */
+#define WHO_AM_I 0x0F /* WhoAmI register */
+#define CTRL_REG1 0x20 /* power / ODR control reg */
+#define CTRL_REG2 0x21 /* boot reg */
+#define CTRL_REG3 0x22 /* interrupt control reg */
+
+#define STATUS_REG 0X27 /* status reg */
+
+#define PRESS_OUT_L OUTDATA_REG /* output data */
+
+#define REF_P_L INDATA_REG /* pressure reference L */
+#define REF_P_H 0x31 /* pressure reference H */
+#define THS_P_L 0x32 /* pressure threshold L */
+#define THS_P_H 0x33 /* pressure threshold H */
+
+#define INT_CFG 0x34 /* interrupt config */
+#define INT_SRC 0x35 /* interrupt source */
+#define INT_ACK 0x36 /* interrupt acknoledge */
+
+
+/* Barometer and Termometer output data rate ODR */
+#define LPS001WP_PRS_ODR_MASK 0x30 /* Mask to access odr bits only */
+#define LPS001WP_PRS_ODR_7_1 0x00 /* 7Hz baro and 1Hz term ODR */
+#define LPS001WP_PRS_ODR_7_7 0x01 /* 7Hz baro and 7Hz term ODR */
+#define LPS001WP_PRS_ODR_12_12 0x11 /* 12.5Hz baro and 12.5Hz term ODR */
+
+/* control bit masks */
+#define LPS001WP_PRS_ENABLE_MASK 0x40
+#define LPS001WP_PRS_DIFF_MASK 0x08
+#define LPS001WP_PRS_LPOW_MASK 0x80
+
+#define LPS001WP_PRS_DIFF_ON 0x08
+#define LPS001WP_PRS_DIFF_OFF 0x00
+
+#define LPS001WP_PRS_LPOW_ON 0x80
+#define LPS001WP_PRS_LPOW_OFF 0x00
+
+#define FUZZ 0
+#define FLAT 0
+#define I2C_AUTO_INCREMENT 0x80
+
+/* RESUME STATE INDICES */
+#define LPS001WP_RES_CTRL_REG1 0
+#define LPS001WP_RES_CTRL_REG2 1
+#define LPS001WP_RES_CTRL_REG3 2
+#define LPS001WP_RES_REF_P_L 3
+#define LPS001WP_RES_REF_P_H 4
+#define LPS001WP_RES_THS_P_L 5
+#define LPS001WP_RES_THS_P_H 6
+#define LPS001WP_RES_INT_CFG 7
+#define LPS001WP_RESUME_ENTRIES 8
+
+
+static const struct {
+ unsigned int cutoff_ms;
+ unsigned int mask;
+} lps001wp_prs_odr_table[] = {
+ {80, LPS001WP_PRS_ODR_12_12 },
+ {143, LPS001WP_PRS_ODR_7_7 },
+ {1000, LPS001WP_PRS_ODR_7_1 },
+};
+
+struct lps001wp_prs_data {
+ struct i2c_client *client;
+ struct lps001wp_prs_platform_data *pdata;
+
+ struct mutex lock;
+ struct delayed_work input_work;
+
+ struct input_dev *input_dev;
+
+ int hw_initialized;
+ /* hw_working=-1 means not tested yet */
+ int hw_working;
+ u8 pressure_delta_enabled;
+ u8 lpowmode_enabled ;
+
+ atomic_t enabled;
+ int on_before_suspend;
+
+ u8 resume_state[LPS001WP_RESUME_ENTRIES];
+
+#ifdef DEBUG
+ u8 reg_addr;
+#endif
+};
+
+struct outputdata {
+ u16 abspress;
+ s16 temperature;
+ s16 deltapress;
+};
+
+static int lps001wp_prs_i2c_read(struct lps001wp_prs_data *prs,
+ u8 *buf, int len)
+{
+ int err;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = prs->client->addr,
+ .flags = prs->client->flags & I2C_M_TEN,
+ .len = 1,
+ .buf = buf,
+ }, {
+ .addr = prs->client->addr,
+ .flags = (prs->client->flags & I2C_M_TEN) | I2C_M_RD,
+ .len = len,
+ .buf = buf,
+ },
+ };
+
+
+ err = i2c_transfer(prs->client->adapter, msgs, 2);
+ if (err != 2) {
+ dev_err(&prs->client->dev, "read transfer error\n");
+ err = -EIO;
+ }
+ return 0;
+}
+
+static int lps001wp_prs_i2c_write(struct lps001wp_prs_data *prs,
+ u8 *buf, int len)
+{
+ int err;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = prs->client->addr,
+ .flags = prs->client->flags & I2C_M_TEN,
+ .len = len + 1,
+ .buf = buf,
+ },
+ };
+
+ err = i2c_transfer(prs->client->adapter, msgs, 1);
+ if (err != 1) {
+ dev_err(&prs->client->dev, "write transfer error\n");
+ err = -EIO;
+ }
+ return 0;
+}
+
+static int lps001wp_prs_i2c_update(struct lps001wp_prs_data *prs,
+ u8 reg_address, u8 mask, u8 new_bit_values)
+{
+ int err;
+ u8 rdbuf[1] = { reg_address };
+ u8 wrbuf[2] = { reg_address , 0x00 };
+
+ u8 init_val;
+ u8 updated_val;
+ err = lps001wp_prs_i2c_read(prs, rdbuf, 1);
+ if (!(err < 0)) {
+ init_val = rdbuf[0];
+ updated_val = ((mask & new_bit_values) | ((~mask) & init_val));
+ wrbuf[1] = updated_val;
+ err = lps001wp_prs_i2c_write(prs, wrbuf, 1);
+ }
+ return err;
+}
+
+static int lps001wp_prs_register_write(struct lps001wp_prs_data *prs, u8 *buf,
+ u8 reg_address, u8 new_value)
+{
+ int err;
+
+ /* Sets configuration register at reg_address
+ * NOTE: this is a straight overwrite */
+ buf[0] = reg_address;
+ buf[1] = new_value;
+ err = lps001wp_prs_i2c_write(prs, buf, 1);
+ if (err < 0)
+ return err;
+
+ return err;
+}
+
+static int lps001wp_prs_register_read(struct lps001wp_prs_data *prs, u8 *buf,
+ u8 reg_address)
+{
+ int err;
+ buf[0] = reg_address;
+ err = lps001wp_prs_i2c_read(prs, buf, 1);
+ return err;
+}
+
+static int lps001wp_prs_register_update(struct lps001wp_prs_data *prs, u8 *buf,
+ u8 reg_address, u8 mask, u8 new_bit_values)
+{
+ int err;
+ u8 init_val;
+ u8 updated_val;
+ err = lps001wp_prs_register_read(prs, buf, reg_address);
+ if (!(err < 0)) {
+ init_val = buf[0];
+ updated_val = ((mask & new_bit_values) | ((~mask) & init_val));
+ err = lps001wp_prs_register_write(prs, buf, reg_address,
+ updated_val);
+ }
+ return err;
+}
+
+static int lps001wp_prs_hw_init(struct lps001wp_prs_data *prs)
+{
+ int err;
+ u8 buf[6];
+
+ buf[0] = WHO_AM_I;
+ err = lps001wp_prs_i2c_read(prs, buf, 1);
+ if (err < 0)
+ goto error_firstread;
+ else
+ prs->hw_working = 1;
+ if (buf[0] != WHOAMI_LPS001WP_PRS) {
+ err = -1; /* TODO:choose the right coded error */
+ goto error_unknown_device;
+ }
+
+
+ buf[0] = (I2C_AUTO_INCREMENT | INDATA_REG);
+ buf[1] = prs->resume_state[LPS001WP_RES_REF_P_L];
+ buf[2] = prs->resume_state[LPS001WP_RES_REF_P_H];
+ buf[3] = prs->resume_state[LPS001WP_RES_THS_P_L];
+ buf[4] = prs->resume_state[LPS001WP_RES_THS_P_H];
+ err = lps001wp_prs_i2c_write(prs, buf, 4);
+ if (err < 0)
+ goto error1;
+
+ buf[0] = (I2C_AUTO_INCREMENT | CTRL_REG1);
+ buf[1] = prs->resume_state[LPS001WP_RES_CTRL_REG1];
+ buf[2] = prs->resume_state[LPS001WP_RES_CTRL_REG2];
+ buf[3] = prs->resume_state[LPS001WP_RES_CTRL_REG3];
+ err = lps001wp_prs_i2c_write(prs, buf, 3);
+ if (err < 0)
+ goto error1;
+
+ buf[0] = INT_CFG;
+ buf[1] = prs->resume_state[LPS001WP_RES_INT_CFG];
+ err = lps001wp_prs_i2c_write(prs, buf, 1);
+ if (err < 0)
+ goto error1;
+
+ prs->hw_initialized = 1;
+ return 0;
+
+error_firstread:
+ prs->hw_working = 0;
+ dev_warn(&prs->client->dev, "Error reading WHO_AM_I: is device "
+ "available/working?\n");
+ goto error1;
+error_unknown_device:
+ dev_err(&prs->client->dev,
+ "device unknown. Expected: 0x%x,"
+ " Replies: 0x%x\n", WHOAMI_LPS001WP_PRS, buf[0]);
+error1:
+ prs->hw_initialized = 0;
+ dev_err(&prs->client->dev, "hw init error 0x%x,0x%x: %d\n", buf[0],
+ buf[1], err);
+ return err;
+}
+
+static void lps001wp_prs_device_power_off(struct lps001wp_prs_data *prs)
+{
+ int err;
+ u8 buf[2] = { CTRL_REG1, LPS001WP_PRS_PM_OFF };
+
+ err = lps001wp_prs_i2c_write(prs, buf, 1);
+ if (err < 0)
+ dev_err(&prs->client->dev, "soft power off failed: %d\n", err);
+
+ if (prs->pdata->power_off) {
+ prs->pdata->power_off();
+ prs->hw_initialized = 0;
+ }
+ if (prs->hw_initialized)
+ prs->hw_initialized = 0;
+}
+
+static int lps001wp_prs_device_power_on(struct lps001wp_prs_data *prs)
+{
+ int err = -1;
+
+ if (prs->pdata->power_on) {
+ err = prs->pdata->power_on();
+ if (err < 0) {
+ dev_err(&prs->client->dev,
+ "power_on failed: %d\n", err);
+ return err;
+ }
+ }
+
+ if (!prs->hw_initialized) {
+ err = lps001wp_prs_hw_init(prs);
+ if (prs->hw_working == 1 && err < 0) {
+ lps001wp_prs_device_power_off(prs);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+
+
+int lps001wp_prs_update_odr(struct lps001wp_prs_data *prs, int poll_interval_ms)
+{
+ int err = -1;
+ int i;
+
+ u8 buf[2];
+ u8 updated_val;
+ u8 init_val;
+ u8 new_val;
+ u8 mask = LPS001WP_PRS_ODR_MASK;
+
+ /* Following, looks for the longest possible odr interval scrolling the
+ * odr_table vector from the end (shortest interval) backward (longest
+ * interval), to support the poll_interval requested by the system.
+ * It must be the longest interval lower then the poll interval.*/
+ for (i = ARRAY_SIZE(lps001wp_prs_odr_table) - 1; i >= 0; i--) {
+ if (lps001wp_prs_odr_table[i].cutoff_ms <= poll_interval_ms)
+ break;
+ }
+
+ new_val = lps001wp_prs_odr_table[i].mask;
+
+ /* If device is currently enabled, we need to write new
+ * configuration out to it */
+ if (atomic_read(&prs->enabled)) {
+ buf[0] = CTRL_REG1;
+ err = lps001wp_prs_i2c_read(prs, buf, 1);
+ if (err < 0)
+ goto error;
+ init_val = buf[0];
+ prs->resume_state[LPS001WP_RES_CTRL_REG1] = init_val;
+
+ updated_val = ((mask & new_val) | ((~mask) & init_val));
+ buf[0] = CTRL_REG1;
+ buf[1] = updated_val;
+ err = lps001wp_prs_i2c_write(prs, buf, 1);
+ if (err < 0)
+ goto error;
+ prs->resume_state[LPS001WP_RES_CTRL_REG1] = updated_val;
+ }
+ return err;
+
+error:
+ dev_err(&prs->client->dev, "update odr failed 0x%x,0x%x: %d\n",
+ buf[0], buf[1], err);
+
+ return err;
+}
+
+static int lps001wp_prs_set_press_reference(struct lps001wp_prs_data *prs,
+ u16 new_reference)
+{
+ int err;
+ u8 const reg_addressL = REF_P_L;
+ u8 const reg_addressH = REF_P_H;
+ u8 bit_valuesL, bit_valuesH;
+ u8 buf[2];
+
+ bit_valuesL = (u8) (new_reference & 0x00FF);
+ bit_valuesH = (u8)((new_reference & 0xFF00) >> 8);
+
+ err = lps001wp_prs_register_write(prs, buf, reg_addressL,
+ bit_valuesL);
+ if (err < 0)
+ return err;
+ err = lps001wp_prs_register_write(prs, buf, reg_addressH,
+ bit_valuesH);
+ if (err < 0) {
+ lps001wp_prs_register_write(prs, buf, reg_addressL,
+ prs->resume_state[LPS001WP_RES_REF_P_L]);
+ return err;
+ }
+ prs->resume_state[LPS001WP_RES_REF_P_L] = bit_valuesL;
+ prs->resume_state[LPS001WP_RES_REF_P_H] = bit_valuesH;
+ return err;
+}
+
+static int lps001wp_prs_get_press_reference(struct lps001wp_prs_data *prs,
+ u16 *buf16)
+{
+ int err;
+ u8 bit_valuesL, bit_valuesH;
+ u8 buf[2];
+ u16 temp = 0;
+
+ err = lps001wp_prs_register_read(prs, buf, REF_P_L);
+ if (err < 0)
+ return err;
+ bit_valuesL = buf[0];
+ err = lps001wp_prs_register_read(prs, buf, REF_P_H);
+ if (err < 0)
+ return err;
+ bit_valuesH = buf[0];
+
+ temp = (((u16) bit_valuesH) << 8);
+ *buf16 = (temp | ((u16) bit_valuesL));
+
+ return err;
+}
+
+static int lps001wp_prs_lpow_manage(struct lps001wp_prs_data *prs, u8 control)
+{
+ int err;
+ u8 buf[2];
+ u8 const mask = LPS001WP_PRS_LPOW_MASK;
+ u8 bit_values = LPS001WP_PRS_LPOW_OFF;
+
+ if (control)
+ bit_values = LPS001WP_PRS_LPOW_ON;
+
+ err = lps001wp_prs_register_update(prs, buf, CTRL_REG1,
+ mask, bit_values);
+
+ if (err < 0)
+ return err;
+ prs->resume_state[LPS001WP_RES_CTRL_REG1] = ((mask & bit_values) |
+ (~mask & prs->resume_state[LPS001WP_RES_CTRL_REG1]));
+ if (bit_values == LPS001WP_PRS_LPOW_ON)
+ prs->lpowmode_enabled = 1;
+ else
+ prs->lpowmode_enabled = 0;
+ return err;
+}
+
+static int lps001wp_prs_diffen_manage(struct lps001wp_prs_data *prs, u8 control)
+{
+ int err;
+ u8 buf[2];
+ u8 const mask = LPS001WP_PRS_DIFF_MASK;
+ u8 bit_values = LPS001WP_PRS_DIFF_OFF;
+
+ if (control)
+ bit_values = LPS001WP_PRS_DIFF_ON;
+
+ err = lps001wp_prs_register_update(prs, buf, CTRL_REG1,
+ mask, bit_values);
+
+ if (err < 0)
+ return err;
+ prs->resume_state[LPS001WP_RES_CTRL_REG1] = ((mask & bit_values) |
+ (~mask & prs->resume_state[LPS001WP_RES_CTRL_REG1]));
+ prs->pressure_delta_enabled = !!(bit_values == LPS001WP_PRS_DIFF_ON);
+ return err;
+}
+
+
+static int lps001wp_prs_get_presstemp_data(struct lps001wp_prs_data *prs,
+ struct outputdata *out)
+{
+ int err;
+ /* Data bytes from hardware PRESS_OUT_L, PRESS_OUT_H,
+ * TEMP_OUT_L, TEMP_OUT_H,
+ * DELTA_L, DELTA_H */
+ u8 prs_data[6] = {
+ (I2C_AUTO_INCREMENT | OUTDATA_REG),
+ };
+
+ int regToRead = 4;
+
+ if (prs->pressure_delta_enabled)
+ regToRead = 6;
+
+ err = lps001wp_prs_i2c_read(prs, prs_data, regToRead);
+ if (err < 0)
+ return err;
+
+ out->abspress = ((((u16) prs_data[1] << 8) | ((u16) prs_data[0])));
+ out->temperature = ((s16) (((u16) prs_data[3] << 8) |
+ ((u16)prs_data[2])));
+ /* if not enabled delta output is set to zero */
+ out->deltapress = ((s16) (((u16) prs_data[5] << 8) |
+ ((u16)prs_data[4])));
+
+ return err;
+}
+
+static void lps001wp_prs_report_values(struct lps001wp_prs_data *prs,
+ struct outputdata *out)
+{
+ input_report_abs(prs->input_dev, ABS_PR, out->abspress);
+ input_report_abs(prs->input_dev, ABS_TEMP, out->temperature);
+ input_report_abs(prs->input_dev, ABS_DLTPR, out->deltapress);
+ input_sync(prs->input_dev);
+}
+
+static int lps001wp_prs_enable(struct lps001wp_prs_data *prs)
+{
+ int err;
+
+ if (!atomic_cmpxchg(&prs->enabled, 0, 1)) {
+ err = lps001wp_prs_device_power_on(prs);
+ if (err < 0) {
+ atomic_set(&prs->enabled, 0);
+ return err;
+ }
+ schedule_delayed_work(&prs->input_work,
+ msecs_to_jiffies(prs->pdata->poll_interval));
+ }
+
+ return 0;
+}
+
+static int lps001wp_prs_disable(struct lps001wp_prs_data *prs)
+{
+ if (atomic_cmpxchg(&prs->enabled, 1, 0)) {
+ cancel_delayed_work_sync(&prs->input_work);
+ lps001wp_prs_device_power_off(prs);
+ }
+
+ return 0;
+}
+
+static ssize_t attr_polling_period_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int val;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ mutex_lock(&prs->lock);
+ val = prs->pdata->poll_interval;
+ mutex_unlock(&prs->lock);
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t attr_polling_period_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ unsigned long interval_ms;
+
+ if (strict_strtoul(buf, 10, &interval_ms))
+ return -EINVAL;
+ if (!interval_ms)
+ return -EINVAL;
+ mutex_lock(&prs->lock);
+ prs->pdata->poll_interval = interval_ms;
+ lps001wp_prs_update_odr(prs, interval_ms);
+ mutex_unlock(&prs->lock);
+ return size;
+}
+
+static ssize_t attr_enable_differential_output_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ u8 val;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ mutex_lock(&prs->lock);
+ val = prs->pressure_delta_enabled;
+ mutex_unlock(&prs->lock);
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t attr_enable_differential_output_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ unsigned long val;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ mutex_lock(&prs->lock);
+ lps001wp_prs_diffen_manage(prs, (u8) val);
+ mutex_unlock(&prs->lock);
+ return size;
+}
+
+static ssize_t attr_enable_device_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ int val = atomic_read(&prs->enabled);
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t attr_enable_device_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ unsigned long val;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val)
+ lps001wp_prs_enable(prs);
+ else
+ lps001wp_prs_disable(prs);
+
+ return size;
+}
+
+static ssize_t attr_pressure_reference_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int err;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ u16 val = 0;
+
+ mutex_lock(&prs->lock);
+ err = lps001wp_prs_get_press_reference(prs, &val);
+ mutex_unlock(&prs->lock);
+ if (err < 0)
+ return err;
+
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t attr_pressure_reference_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int err;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ unsigned long val = 0;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val < PR_ABS_MIN || val > PR_ABS_MAX)
+ return -EINVAL;
+
+ mutex_lock(&prs->lock);
+ err = lps001wp_prs_set_press_reference(prs, val);
+ mutex_unlock(&prs->lock);
+ if (err < 0)
+ return err;
+ return size;
+}
+
+
+static ssize_t attr_enable_lowpowermode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ u8 val;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ mutex_lock(&prs->lock);
+ val = prs->lpowmode_enabled;
+ mutex_unlock(&prs->lock);
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t attr_enable_lowpowermode_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int err;
+ struct lps001wp_prs_data *prs = dev_get_drvdata(dev);
+ unsigned long val;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ mutex_lock(&prs->lock);
+ err = lps001wp_prs_lpow_manage(prs, (u8) val);
+ /*This looks like it might involve some magic numbers. Documentation
+ might show be to be wrong, but it certainly looks suspicious.
+*/
+ mutex_unlock(&prs->lock);
+ if (err < 0)
+ return err;
+
+ return size;
+}
+
+static struct device_attribute attributes[] = {
+ __ATTR(enable_device, 0664,
+ attr_enable_device_show,
+ attr_enable_device_store),
+ __ATTR(poll_period_ms, 0664,
+ attr_polling_period_show,
+ attr_polling_period_store),
+ __ATTR(enable_differential_output, 0664,
+ attr_enable_differential_output_show,
+ attr_enable_differential_output_store),
+ __ATTR(pressure_reference_level, 0664,
+ attr_pressure_reference_show,
+ attr_pressure_reference_store),
+ __ATTR(lowpower_enable, 0664,
+ attr_enable_lowpowermode_show,
+ attr_enable_lowpowermode_store),
+};
+
+static int lps001wp_prs_create_sysfs_interfaces(struct device *dev)
+{
+ int i, ret;
+ for (i = 0; i < ARRAY_SIZE(attributes); i++)
+ ret = device_create_file(dev, attributes + i);
+ if (ret < 0)
+ goto error;
+ return 0;
+
+error:
+ for ( ; i >= 0; i--)
+ device_remove_file(dev, attributes + i);
+ dev_err(dev, "%s:Unable to create interface\n", __func__);
+ return ret;
+}
+
+static void lps001wp_prs_remove_sysfs_interfaces(struct device *dev)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(attributes); i++)
+ device_remove_file(dev, attributes + i);
+}
+
+
+static void lps001wp_prs_input_work_func(struct work_struct *work)
+{
+ struct lps001wp_prs_data *prs = container_of(
+ (struct delayed_work *)work,
+ struct lps001wp_prs_data,
+ input_work);
+
+ struct outputdata output;
+ int err;
+
+ mutex_lock(&prs->lock);
+ err = lps001wp_prs_get_presstemp_data(prs, &output);
+ if (err < 0)
+ dev_err(&prs->client->dev, "get_pressure_data failed\n");
+ else
+ lps001wp_prs_report_values(prs, &output);
+
+ schedule_delayed_work(&prs->input_work,
+ msecs_to_jiffies(prs->pdata->poll_interval));
+ mutex_unlock(&prs->lock);
+}
+
+int lps001wp_prs_input_open(struct input_dev *input)
+{
+ struct lps001wp_prs_data *prs = input_get_drvdata(input);
+
+ return lps001wp_prs_enable(prs);
+}
+
+void lps001wp_prs_input_close(struct input_dev *dev)
+{
+ lps001wp_prs_disable(input_get_drvdata(dev));
+}
+
+
+static int lps001wp_prs_validate_pdata(struct lps001wp_prs_data *prs)
+{
+ /* Enforce minimum polling interval */
+ if (prs->pdata->poll_interval < prs->pdata->min_interval) {
+ dev_err(&prs->client->dev, "minimum poll interval violated\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int lps001wp_prs_input_init(struct lps001wp_prs_data *prs)
+{
+ int err;
+
+ INIT_DELAYED_WORK(&prs->input_work, lps001wp_prs_input_work_func);
+ prs->input_dev = input_allocate_device();
+ if (!prs->input_dev) {
+ err = -ENOMEM;
+ dev_err(&prs->client->dev, "input device allocate failed\n");
+ goto err0;
+ }
+
+ prs->input_dev->open = lps001wp_prs_input_open;
+ prs->input_dev->close = lps001wp_prs_input_close;
+ prs->input_dev->name = LPS001WP_PRS_DEV_NAME;
+ prs->input_dev->id.bustype = BUS_I2C;
+ prs->input_dev->dev.parent = &prs->client->dev;
+
+ input_set_drvdata(prs->input_dev, prs);
+
+ set_bit(EV_ABS, prs->input_dev->evbit);
+
+ input_set_abs_params(prs->input_dev, ABS_PR,
+ PR_ABS_MIN, PR_ABS_MAX, FUZZ, FLAT);
+ input_set_abs_params(prs->input_dev, ABS_TEMP,
+ PR_DLT_MIN, PR_DLT_MAX, FUZZ, FLAT);
+ input_set_abs_params(prs->input_dev, ABS_DLTPR,
+ TEMP_MIN, TEMP_MAX, FUZZ, FLAT);
+
+
+ prs->input_dev->name = "LPS001WP barometer";
+
+ err = input_register_device(prs->input_dev);
+ if (err) {
+ dev_err(&prs->client->dev,
+ "unable to register input polled device %s\n",
+ prs->input_dev->name);
+ goto err1;
+ }
+
+ return 0;
+
+err1:
+ input_free_device(prs->input_dev);
+err0:
+ return err;
+}
+
+static void lps001wp_prs_input_cleanup(struct lps001wp_prs_data *prs)
+{
+ input_unregister_device(prs->input_dev);
+ input_free_device(prs->input_dev);
+}
+
+static int __devinit lps001wp_prs_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct lps001wp_prs_data *prs;
+ int err = -1;
+ int tempvalue;
+
+ pr_info("%s: probe start.\n", LPS001WP_PRS_DEV_NAME);
+
+ if (client->dev.platform_data == NULL) {
+ dev_err(&client->dev, "platform data is NULL. exiting.\n");
+ err = -ENODATA;
+ goto err_exit_check_functionality_failed;
+ }
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(&client->dev, "client not i2c capable\n");
+ err = -EIO;
+ goto err_exit_check_functionality_failed;
+ }
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA)) {
+ dev_err(&client->dev, "client not smb-i2c capable\n");
+ err = -EIO;
+ goto err_exit_check_functionality_failed;
+ }
+
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_I2C_BLOCK)){
+ dev_err(&client->dev, "client not smb-i2c block capable\n");
+ err = -EIO;
+ goto err_exit_check_functionality_failed;
+ }
+
+
+ prs = kzalloc(sizeof(struct lps001wp_prs_data), GFP_KERNEL);
+ if (prs == NULL) {
+ err = -ENOMEM;
+ dev_err(&client->dev,
+ "failed to allocate memory for module data: "
+ "%d\n", err);
+ goto err_exit_alloc_data_failed;
+ }
+
+ mutex_init(&prs->lock);
+ mutex_lock(&prs->lock);
+
+ prs->client = client;
+ i2c_set_clientdata(client, prs);
+
+
+ if (i2c_smbus_read_byte(client) < 0) {
+ printk(KERN_ERR "i2c_smbus_read_byte error\n");
+ goto err_mutexunlockfreedata;
+ }
+
+ /* read chip id */
+ tempvalue = i2c_smbus_read_word_data(client, WHO_AM_I);
+ if ((tempvalue & 0x00FF) == WHOAMI_LPS001WP_PRS) {
+ printk(KERN_INFO "%s I2C driver registered\n",
+ LPS001WP_PRS_DEV_NAME);
+ } else {
+ prs->client = NULL;
+ printk(KERN_ERR "I2C driver not registered!"
+ " Device unknown\n");
+ err = -ENODEV;
+ goto err_mutexunlockfreedata;
+ }
+
+ prs->pdata = kmemdup(client->dev.platform_data,
+ sizeof(*prs->pdata), GFP_KERNEL);
+ if (!prs->pdata) {
+ err = -ENOMEM;
+ dev_err(&client->dev,
+ "failed to allocate memory for pdata: %d\n",
+ err);
+ goto err_mutexunlockfreedata;
+ }
+
+
+ err = lps001wp_prs_validate_pdata(prs);
+ if (err < 0) {
+ dev_err(&client->dev, "failed to validate platform data\n");
+ goto err_exit_kfree_pdata;
+ }
+
+ if (prs->pdata->init) {
+ err = prs->pdata->init();
+ if (err < 0) {
+ dev_err(&client->dev, "init failed: %d\n", err);
+ goto err_exit_pointer;
+ }
+ }
+
+ /* init registers which need values different from zero:
+ zeros are set by kzallok above */
+ prs->resume_state[LPS001WP_RES_CTRL_REG1] = LPS001WP_PRS_PM_NORMAL;
+
+ err = lps001wp_prs_device_power_on(prs);
+ if (err < 0) {
+ dev_err(&client->dev, "power on failed: %d\n", err);
+ goto err_exit_pointer;
+ }
+
+ prs->pressure_delta_enabled = 0;
+ prs->lpowmode_enabled = 0;
+ atomic_set(&prs->enabled, 1);
+
+ err = lps001wp_prs_update_odr(prs, prs->pdata->poll_interval);
+ if (err < 0) {
+ dev_err(&client->dev, "update_odr failed\n");
+ goto err_power_off;
+ }
+
+ err = lps001wp_prs_input_init(prs);
+ if (err < 0) {
+ dev_err(&client->dev, "input init failed\n");
+ goto err_power_off;
+ }
+
+
+ err = lps001wp_prs_create_sysfs_interfaces(&client->dev);
+ if (err < 0)
+ goto err_input_cleanup;
+
+ lps001wp_prs_device_power_off(prs);
+
+ /* As default, do not report information */
+ atomic_set(&prs->enabled, 0);
+
+
+ mutex_unlock(&prs->lock);
+
+ dev_info(&client->dev, "%s: probed\n", LPS001WP_PRS_DEV_NAME);
+
+ return 0;
+
+/*
+err_remove_sysfs_int:
+ lps001wp_prs_remove_sysfs_interfaces(&client->dev);
+*/
+err_input_cleanup:
+ lps001wp_prs_input_cleanup(prs);
+err_power_off:
+ lps001wp_prs_device_power_off(prs);
+err_exit_pointer:
+ if (prs->pdata->exit)
+ prs->pdata->exit();
+err_exit_kfree_pdata:
+ kfree(prs->pdata);
+
+err_mutexunlockfreedata:
+ mutex_unlock(&prs->lock);
+ kfree(prs);
+err_exit_alloc_data_failed:
+err_exit_check_functionality_failed:
+ printk(KERN_ERR "%s: Driver Init failed\n", LPS001WP_PRS_DEV_NAME);
+ return err;
+}
+
+static int __devexit lps001wp_prs_remove(struct i2c_client *client)
+{
+ struct lps001wp_prs_data *prs = i2c_get_clientdata(client);
+
+ lps001wp_prs_input_cleanup(prs);
+ lps001wp_prs_device_power_off(prs);
+ lps001wp_prs_remove_sysfs_interfaces(&client->dev);
+
+ if (prs->pdata->exit)
+ prs->pdata->exit();
+ kfree(prs->pdata);
+ kfree(prs);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int lps001wp_prs_resume(struct i2c_client *client)
+{
+ struct lps001wp_prs_data *prs = i2c_get_clientdata(client);
+
+ if (prs->on_before_suspend)
+ return lps001wp_prs_enable(prs);
+ return 0;
+}
+
+static int lps001wp_prs_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ struct lps001wp_prs_data *prs = i2c_get_clientdata(client);
+
+ prs->on_before_suspend = atomic_read(&prs->enabled);
+ return lps001wp_prs_disable(prs);
+}
+#else
+#define lps001wp_prs_resume NULL
+#define lps001wp_prs_suspend NULL
+#endif /* CONFIG_PM */
+
+static const struct i2c_device_id lps001wp_prs_id[]
+ = { { LPS001WP_PRS_DEV_NAME, 0}, { },};
+
+MODULE_DEVICE_TABLE(i2c, lps001wp_prs_id);
+
+static struct i2c_driver lps001wp_prs_driver = {
+ .driver = {
+ .name = LPS001WP_PRS_DEV_NAME,
+ .owner = THIS_MODULE,
+ },
+ .probe = lps001wp_prs_probe,
+ .remove = __devexit_p(lps001wp_prs_remove),
+ .id_table = lps001wp_prs_id,
+ .resume = lps001wp_prs_resume,
+ .suspend = lps001wp_prs_suspend,
+};
+
+static int __init lps001wp_prs_init(void)
+{
+ return i2c_add_driver(&lps001wp_prs_driver);
+}
+
+static void __exit lps001wp_prs_exit(void)
+{
+ i2c_del_driver(&lps001wp_prs_driver);
+ return;
+}
+
+module_init(lps001wp_prs_init);
+module_exit(lps001wp_prs_exit);
+
+MODULE_DESCRIPTION("STMicrolelectronics lps001wp pressure sensor sysfs driver");
+MODULE_AUTHOR("Matteo Dameno, Carmine Iascone, STMicroelectronics");
+MODULE_LICENSE("GPL");
+
--
1.5.4.3
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