Hi,

On Thu, Aug 11, 2011 at 03:27:26PM +0530, J, KEERTHY wrote:
> On Wed, Aug 10, 2011 at 6:16 PM, Felipe Balbi <balbi@ti.com> wrote:
> > Hi,
> >
> > (why aren't below in Cc ?
> 
> I will add them.
> 
> >
> > HARDWARE MONITORING
> > M:      Jean Delvare <khali@linux-fr.org>
> > M:      Guenter Roeck <guenter.roeck@ericsson.com>
> > L:      lm-sensors@lm-sensors.org
> > W:      http://www.lm-sensors.org/
> > T:      quilt kernel.org/pub/linux/kernel/people/jdelvare/linux-2.6/jdelvare-hwmon/
> > T:      git git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git
> > S:      Maintained
> > F:      Documentation/hwmon/
> > F:      drivers/hwmon/
> > F:      include/linux/hwmon*.h)
> >
> > On Wed, Aug 10, 2011 at 05:55:22PM +0530, Keerthy wrote:
> >> On chip temperature sensor driver. The driver monitors the temperature of
> >> the MPU subsystem of the OMAP4. It sends notifications to the user space if
> >> the temperature crosses user defined thresholds via kobject_uevent interface.
> >> The user is allowed to configure the temperature thresholds vis sysfs nodes
> >> exposed using hwmon interface.
> >>
> >> Signed-off-by: Keerthy <j-keerthy@ti.com>
> >> ---
> >>  drivers/hwmon/Kconfig            |   11 +
> >>  drivers/hwmon/Makefile           |    1 +
> >>  drivers/hwmon/omap_temp_sensor.c |  950 ++++++++++++++++++++++++++++++++++++++
> >>  3 files changed, 962 insertions(+), 0 deletions(-)
> >>  create mode 100644 drivers/hwmon/omap_temp_sensor.c
> >>
> >> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> >> index 5f888f7..9c9cd8b 100644
> >> --- a/drivers/hwmon/Kconfig
> >> +++ b/drivers/hwmon/Kconfig
> >> @@ -323,6 +323,17 @@ config SENSORS_F71805F
> >>         This driver can also be built as a module.  If so, the module
> >>         will be called f71805f.
> >>
> >> +config SENSORS_OMAP_BANDGAP_TEMP_SENSOR
> >> +     bool "OMAP on-die temperature sensor hwmon driver"
> >> +     depends on HWMON && ARCH_OMAP && OMAP_TEMP_SENSOR
> >> +     help
> >> +       If you say yes here you get support for hardware
> >> +       monitoring features of the OMAP on die temperature
> >> +       sensor.
> >> +
> >> +       Continuous conversion programmable delay
> >> +       mode is used for temperature conversion.
> >> +
> >>  config SENSORS_F71882FG
> >>       tristate "Fintek F71882FG and compatibles"
> >>       help
> >> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> >> index 28061cf..d0f89f5 100644
> >> --- a/drivers/hwmon/Makefile
> >> +++ b/drivers/hwmon/Makefile
> >> @@ -91,6 +91,7 @@ obj-$(CONFIG_SENSORS_MAX6639)       += max6639.o
> >>  obj-$(CONFIG_SENSORS_MAX6642)        += max6642.o
> >>  obj-$(CONFIG_SENSORS_MAX6650)        += max6650.o
> >>  obj-$(CONFIG_SENSORS_MC13783_ADC)+= mc13783-adc.o
> >> +obj-$(CONFIG_SENSORS_OMAP_BANDGAP_TEMP_SENSOR)  += omap_temp_sensor.o
> >>  obj-$(CONFIG_SENSORS_PC87360)        += pc87360.o
> >>  obj-$(CONFIG_SENSORS_PC87427)        += pc87427.o
> >>  obj-$(CONFIG_SENSORS_PCF8591)        += pcf8591.o
> >> diff --git a/drivers/hwmon/omap_temp_sensor.c b/drivers/hwmon/omap_temp_sensor.c
> >> new file mode 100644
> >> index 0000000..15e2559
> >> --- /dev/null
> >> +++ b/drivers/hwmon/omap_temp_sensor.c
> >> @@ -0,0 +1,950 @@
> >> +/*
> >> + * OMAP4 Temperature sensor driver file
> >> + *
> >> + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
> >> + * Author: J Keerthy <j-keerthy@ti.com>
> >> + * Author: Moiz Sonasath <m-sonasath@ti.com>
> >> + *
> >> + * This program is free software; you can redistribute it and/or
> >> + * modify it under the terms of the GNU General Public License
> >> + * version 2 as published by the Free Software Foundation.
> >> + *
> >> + * This program is distributed in the hope that it will be useful, but
> >> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> >> + * General Public License for more details.
> >> + *
> >> + * You should have received a copy of the GNU General Public License
> >> + * along with this program; if not, write to the Free Software
> >> + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
> >> + * 02110-1301 USA
> >> + *
> >> + */
> >> +
> >> +#include <linux/interrupt.h>
> >> +#include <linux/clk.h>
> >
> > why ??
> 
> Clock rate setting functions.

you shouldn't need in drivers.

> >> +#include <linux/io.h>
> >> +#include <linux/debugfs.h>
> >
> > why ??
> 
> It will be removed.
> 
> >
> >> +#include <linux/delay.h>
> >> +#include <linux/slab.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/init.h>
> >> +#include <plat/omap_device.h>
> >
> > why ??
> >
> 
> Context loss count

shouldn't use in drivers.

> >> +#include <linux/module.h>
> >> +#include <linux/kernel.h>
> >> +#include <linux/device.h>
> >> +#include <linux/jiffies.h>
> >> +#include <linux/hwmon.h>
> >> +#include <linux/hwmon-sysfs.h>
> >> +#include <linux/stddef.h>
> >> +#include <linux/sysfs.h>
> >> +#include <linux/err.h>
> >> +#include <linux/types.h>
> >> +#include <linux/mutex.h>
> >> +#include <linux/pm_runtime.h>
> >> +#include <plat/common.h>
> >
> > why ?
> 
> usleep_range function.

plat/common for usleep_range ?? usleep_range is defined in
<linux/delay.h>

> >> +#include <plat/temperature_sensor.h>
> >
> 
> It is the header file with the structure definitions
> used in the driver.

why don't you put in <linux/platform_data/....> ??

> >> +#include <mach/ctrl_module_core_44xx.h>
> >
> > why ?
> 
> It will be removed
> 
> >
> >> +#include <mach/gpio.h>
> >
> > linux/gpio.h for crying out loud... how many times Russell has to say
> > the exact same thing ??????
> >
> 
> It will be removed

oh, you don't even use any gpio ? Why do you blindly add so many headers
if you don't need them ???

> >> +#define TSHUT_THRESHOLD_HOT  122000  /* 122 deg C */
> >> +#define TSHUT_THRESHOLD_COLD 100000  /* 100 deg C */
> >> +#define BGAP_THRESHOLD_T_HOT 73000   /* 73 deg C */
> >> +#define BGAP_THRESHOLD_T_COLD        71000   /* 71 deg C */
> >> +#define OMAP_ADC_START_VALUE 530
> >> +#define OMAP_ADC_END_VALUE   923
> >> +
> >> +/*
> >> + * omap_temp_sensor structure
> >> + * @hwmon_dev - device pointer
> >> + * @clock - Clock pointer
> >> + * @registers - Pointer to structure with register offsets and bitfields
> >> + * @sensor_mutex - Mutex for sysfs, irq and PM
> >> + * @irq - MPU Irq number for thermal alert
> >> + * @phy_base - Physical base of the temp I/O
> >> + * @clk_rate - Holds current clock rate
> >> + * @temp_sensor_ctrl - temp sensor control register value
> >> + * @bg_ctrl - bandgap ctrl register value
> >> + * @bg_counter - bandgap counter value
> >> + * @bg_threshold - bandgap threshold register value
> >> + * @temp_sensor_tshut_threshold - bandgap tshut register value
> >> + * @is_efuse_valid - Flag to determine if efuse is valid or not
> >> + * @clk_on - Manages the current clock state
> >> + */
> >> +struct omap_temp_sensor {
> >> +     struct device           *hwmon_dev;
> >> +     struct clk              *clock;
> >> +     struct omap_temp_sensor_registers *registers;
> >> +     struct mutex            sensor_mutex; /* Mutex for sysfs, irq and PM */
> >> +     unsigned int            irq;
> >> +     void __iomem            *phy_base;
> >> +     u32                     clk_rate;
> >> +     u32                     temp_sensor_ctrl;
> >> +     u32                     bg_ctrl;
> >> +     u32                     bg_counter;
> >> +     u32                     bg_threshold;
> >> +     u32                     temp_sensor_tshut_threshold;
> >> +     bool                    is_efuse_valid;
> >> +     bool                    clk_on;
> >> +};
> >> +
> >> +/*
> >> + * Temperature values in milli degree celsius
> >> + * ADC code values from 530 to 923
> >> + */
> >> +static int adc_to_temp[] = {
> >> +     -40000, -40000, -40000, -40000, -39800, -39400, -39000, -38600, -38200,
> >> +     -37800, -37300, -36800, -36400, -36000, -35600, -35200, -34800,
> >> +     -34300, -33800, -33400, -33000, -32600, -32200, -31800, -31300,
> >> +     -30800, -30400, -30000, -29600, -29200, -28700, -28200, -27800,
> >> +     -27400, -27000, -26600, -26200, -25700, -25200, -24800, -24400,
> >> +     -24000, -23600, -23200, -22700, -22200, -21800, -21400, -21000,
> >> +     -20600, -20200, -19700, -19200, -18800, -18400, -18000, -17600,
> >> +     -17200, -16700, -16200, -15800, -15400, -15000, -14600, -14200,
> >> +     -13700, -13200, -12800, -12400, -12000, -11600, -11200, -10700,
> >> +     -10200, -9800, -9400, -9000, -8600, -8200, -7700, -7200, -6800,
> >> +     -6400, -6000, -5600, -5200, -4800, -4300, -3800, -3400, -3000,
> >> +     -2600, -2200, -1800, -1300, -800, -400, 0, 400, 800, 1200, 1600,
> >> +     2100, 2600, 3000, 3400, 3800, 4200, 4600, 5100, 5600, 6000, 6400,
> >> +     6800, 7200, 7600, 8000, 8500, 9000, 9400, 9800, 10200, 10600, 11000,
> >> +     11400, 11900, 12400, 12800, 13200, 13600, 14000, 14400, 14800,
> >> +     15300, 15800, 16200, 16600, 17000, 17400, 17800, 18200, 18700,
> >> +     19200, 19600, 20000, 20400, 20800, 21200, 21600, 22100, 22600,
> >> +     23000, 23400, 23800, 24200, 24600, 25000, 25400, 25900, 26400,
> >> +     26800, 27200, 27600, 28000, 28400, 28800, 29300, 29800, 30200,
> >> +     30600, 31000, 31400, 31800, 32200, 32600, 33100, 33600, 34000,
> >> +     34400, 34800, 35200, 35600, 36000, 36400, 36800, 37300, 37800,
> >> +     38200, 38600, 39000, 39400, 39800, 40200, 40600, 41100, 41600,
> >> +     42000, 42400, 42800, 43200, 43600, 44000, 44400, 44800, 45300,
> >> +     45800, 46200, 46600, 47000, 47400, 47800, 48200, 48600, 49000,
> >> +     49500, 50000, 50400, 50800, 51200, 51600, 52000, 52400, 52800,
> >> +     53200, 53700, 54200, 54600, 55000, 55400, 55800, 56200, 56600,
> >> +     57000, 57400, 57800, 58200, 58700, 59200, 59600, 60000, 60400,
> >> +     60800, 61200, 61600, 62000, 62400, 62800, 63300, 63800, 64200,
> >> +     64600, 65000, 65400, 65800, 66200, 66600, 67000, 67400, 67800,
> >> +     68200, 68700, 69200, 69600, 70000, 70400, 70800, 71200, 71600,
> >> +     72000, 72400, 72800, 73200, 73600, 74100, 74600, 75000, 75400,
> >> +     75800, 76200, 76600, 77000, 77400, 77800, 78200, 78600, 79000,
> >> +     79400, 79800, 80300, 80800, 81200, 81600, 82000, 82400, 82800,
> >> +     83200, 83600, 84000, 84400, 84800, 85200, 85600, 86000, 86400,
> >> +     86800, 87300, 87800, 88200, 88600, 89000, 89400, 89800, 90200,
> >> +     90600, 91000, 91400, 91800, 92200, 92600, 93000, 93400, 93800,
> >> +     94200, 94600, 95000, 95500, 96000, 96400, 96800, 97200, 97600,
> >> +     98000, 98400, 98800, 99200, 99600, 100000, 100400, 100800, 101200,
> >> +     101600, 102000, 102400, 102800, 103200, 103600, 104000, 104400,
> >> +     104800, 105200, 105600, 106100, 106600, 107000, 107400, 107800,
> >> +     108200, 108600, 109000, 109400, 109800, 110200, 110600, 111000,
> >> +     111400, 111800, 112200, 112600, 113000, 113400, 113800, 114200,
> >> +     114600, 115000, 115400, 115800, 116200, 116600, 117000, 117400,
> >> +     117800, 118200, 118600, 119000, 119400, 119800, 120200, 120600,
> >> +     121000, 121400, 121800, 122200, 122600, 123000
> >> +};
> >> +
> >> +static unsigned long omap_temp_sensor_readl(struct omap_temp_sensor
> >> +                                         *temp_sensor, u32 reg)
> >> +{
> >> +     return __raw_readl(temp_sensor->phy_base + reg);
> >> +}
> >> +
> >> +static void omap_temp_sensor_writel(struct omap_temp_sensor *temp_sensor,
> >> +                                 u32 val, u32 reg)
> >> +{
> >> +     __raw_writel(val, (temp_sensor->phy_base + reg));
> >> +}
> >> +
> >> +static int adc_to_temp_conversion(int adc_val)
> >> +{
> >> +     return adc_to_temp[adc_val - OMAP_ADC_START_VALUE];
> >> +}
> >> +
> >> +static int temp_to_adc_conversion(long temp)
> >> +{
> >> +     int i;
> >> +
> >> +     for (i = 0; i <= OMAP_ADC_END_VALUE - OMAP_ADC_START_VALUE; i++)
> >> +             if (temp < adc_to_temp[i])
> >> +                     return OMAP_ADC_START_VALUE + i - 1;
> >> +
> >> +     return -EINVAL;
> >> +}
> >> +
> >> +static void omap_configure_temp_sensor_thresholds(struct omap_temp_sensor
> >> +                                               *temp_sensor)
> >> +{
> >> +     u32 temp, t_hot, t_cold, tshut_hot, tshut_cold;
> >> +
> >> +     t_hot = temp_to_adc_conversion(BGAP_THRESHOLD_T_HOT);
> >> +     t_cold = temp_to_adc_conversion(BGAP_THRESHOLD_T_COLD);
> >> +
> >> +     /* Configure the TALERT thresholds */
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     temp |= (t_hot << __ffs(temp_sensor->registers->threshold_thot_mask)) |
> >> +             (t_cold << __ffs(temp_sensor->registers->threshold_tcold_mask));
> >> +     omap_temp_sensor_writel(temp_sensor, temp,
> >> +             temp_sensor->registers->bgap_threshold);
> >> +
> >> +     tshut_hot = temp_to_adc_conversion(TSHUT_THRESHOLD_HOT);
> >> +     tshut_cold = temp_to_adc_conversion(TSHUT_THRESHOLD_COLD);
> >> +
> >> +     /* Configure the TSHUT thresholds */
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->thsut_threshold);
> >> +     temp |= (tshut_hot << __ffs(temp_sensor->registers->tshut_hot_mask))
> >> +         | (tshut_cold << __ffs(temp_sensor->registers->tshut_hot_mask));
> >> +     omap_temp_sensor_writel(temp_sensor, temp,
> >> +                     temp_sensor->registers->thsut_threshold);
> >> +}
> >> +
> >> +static void omap_configure_temp_sensor_counter(struct omap_temp_sensor
> >> +                                            *temp_sensor, u32 counter)
> >> +{
> >> +     u32 val;
> >> +
> >> +     val = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_counter);
> >> +     val &= ~(temp_sensor->registers->counter_mask);
> >> +     val |= (counter << __ffs(temp_sensor->registers->counter_mask));
> >> +     omap_temp_sensor_writel(temp_sensor, val,
> >> +                     temp_sensor->registers->bgap_counter);
> >> +}
> >> +
> >> +static void omap_enable_continuous_mode(struct omap_temp_sensor *temp_sensor,
> >> +                                     bool enable)
> >> +{
> >> +     u32 val;
> >> +
> >> +     val = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_mode_ctrl);
> >> +
> >> +     if (enable)
> >> +             val |= (1 << __ffs(temp_sensor->registers->mode_ctrl_mask));
> >> +     else
> >> +             val &= ~(temp_sensor->registers->mode_ctrl_mask);
> >> +
> >> +     omap_temp_sensor_writel(temp_sensor, val,
> >> +                     temp_sensor->registers->bgap_mode_ctrl);
> >> +}
> >> +
> >> +/* Sysfs hook functions */
> >> +
> >> +static ssize_t show_temp_max(struct device *dev,
> >> +                     struct device_attribute *devattr, char *buf)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     int temp;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     temp = (temp & temp_sensor->registers->threshold_thot_mask)
> >> +                     >> __ffs(temp_sensor->registers->threshold_thot_mask);
> >> +
> >> +     if (temp < OMAP_ADC_START_VALUE || temp > OMAP_ADC_END_VALUE) {
> >> +             dev_err(dev, "invalid value\n");
> >> +             goto out;
> >> +     }
> >> +     temp = adc_to_temp_conversion(temp);
> >> +
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +
> >> +     return snprintf(buf, 16, "%d\n", temp);
> >> +}
> >> +
> >> +static ssize_t set_temp_max(struct device *dev,
> >> +                         struct device_attribute *devattr,
> >> +                         const char *buf, size_t count)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     long                    val;
> >> +     u32                     reg_val, t_cold, t_hot, temp;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     if (strict_strtol(buf, 10, &val)) {
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     t_hot = temp_to_adc_conversion(val);
> >> +     if ((t_hot < OMAP_ADC_START_VALUE || t_hot > OMAP_ADC_END_VALUE)) {
> >> +             dev_err(dev, "invalid range\n");
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     /* obtain the T cold value */
> >> +     t_cold = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     t_cold = (t_cold & temp_sensor->registers->threshold_tcold_mask) >>
> >> +                     __ffs(temp_sensor->registers->threshold_tcold_mask);
> >> +
> >> +     if (t_hot < t_cold) {
> >> +             dev_err(dev, "Error! T_HOT value lesser than T_COLD\n");
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     /* write the new t_hot value */
> >> +     reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     reg_val &= ~(temp_sensor->registers->threshold_thot_mask);
> >> +     reg_val |= (t_hot <<
> >> +                     __ffs(temp_sensor->registers->threshold_thot_mask));
> >> +     omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +
> >> +     /* Read the current temperature */
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp &= (temp_sensor->registers->bgap_dtemp_mask);
> >> +
> >> +     /*
> >> +      * If user sets the HIGH threshold(t_hot) greater than the current
> >> +      * temperature(temp) unmask the HOT interrupts
> >> +      */
> >> +     if (t_hot > temp) {
> >> +             reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +             reg_val &= ~(temp_sensor->registers->mask_cold_mask);
> >> +             reg_val |= temp_sensor->registers->mask_hot_mask;
> >> +             omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +     }
> >> +
> >> +     /*
> >> +      * If current temperature is in-between the hot and cold thresholds,
> >> +      * Enable both masks.
> >> +      */
> >> +     if (temp > t_cold && temp < t_hot) {
> >> +             reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +             reg_val |= temp_sensor->registers->mask_cold_mask;
> >> +             reg_val |= temp_sensor->registers->mask_hot_mask;
> >> +             omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                             OMAP4460_BGAP_CTRL_OFFSET);
> >> +     }
> >> +     /*
> >> +      * else no need to do anything since HW will immediately compare
> >> +      * the new threshold and generate interrupt accordingly
> >> +      */
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +     return count;
> >> +}
> >> +
> >> +static ssize_t show_temp_max_hyst(struct device *dev,
> >> +             struct device_attribute *devattr, char *buf)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     u32                     temp;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +             temp_sensor->registers->bgap_threshold);
> >> +     temp = (temp & temp_sensor->registers->threshold_tcold_mask) >>
> >> +             __ffs(temp_sensor->registers->threshold_tcold_mask);
> >> +
> >> +     if (temp < OMAP_ADC_START_VALUE || temp > OMAP_ADC_END_VALUE) {
> >> +             dev_err(dev, "invalid value\n");
> >> +             goto out;
> >> +     }
> >> +
> >> +     temp = adc_to_temp_conversion(temp);
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +
> >> +     return snprintf(buf, 16, "%d\n", temp);
> >> +}
> >> +
> >> +static ssize_t set_temp_max_hyst(struct device *dev,
> >> +                              struct device_attribute *devattr,
> >> +                              const char *buf, size_t count)
> >> +{
> >> +     struct omap_temp_sensor         *temp_sensor = dev_get_drvdata(dev);
> >> +     u32                             reg_val, t_hot, t_cold, temp;
> >> +     long                            val;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     if (strict_strtol(buf, 10, &val)) {
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     t_cold = temp_to_adc_conversion(val);
> >> +     if (t_cold < OMAP_ADC_START_VALUE || t_cold > OMAP_ADC_END_VALUE) {
> >> +             dev_err(dev, "invalid range");
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     /* obtain the T HOT value */
> >> +     t_hot = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     t_hot = (t_hot & temp_sensor->registers->threshold_thot_mask) >>
> >> +                     __ffs(temp_sensor->registers->threshold_thot_mask);
> >> +
> >> +     if (t_cold > t_hot) {
> >> +             dev_err(dev, "Error! T_COLD value greater than T_HOT\n");
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     /* write the new t_cold value */
> >> +     reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +     reg_val &= ~(temp_sensor->registers->threshold_tcold_mask);
> >> +     reg_val |= (t_cold <<
> >> +                     __ffs(temp_sensor->registers->threshold_tcold_mask));
> >> +     omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                     temp_sensor->registers->bgap_threshold);
> >> +
> >> +     /* Read the current temperature */
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +             temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp &= (temp_sensor->registers->bgap_dtemp_mask);
> >> +
> >> +     /*
> >> +      * If user sets the LOW threshold(t_cold) lower than the current
> >> +      * temperature(temp) unmask the COLD interrupts
> >> +      */
> >> +     if (t_cold < temp) {
> >> +             reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +             reg_val &= ~(temp_sensor->registers->mask_hot_mask);
> >> +             reg_val |= temp_sensor->registers->mask_cold_mask;
> >> +             omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                     temp_sensor->registers->bgap_mask_ctrl);
> >> +     }
> >> +
> >> +     /*
> >> +      * If current temperature is in-between the hot and cold thresholds,
> >> +      * Enable both masks.
> >> +      */
> >> +     if (temp < t_hot && temp > t_cold) {
> >> +             reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +             reg_val |= temp_sensor->registers->mask_cold_mask;
> >> +             reg_val |= temp_sensor->registers->mask_hot_mask;
> >> +             omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                             temp_sensor->registers->bgap_mask_ctrl);
> >> +     }
> >> +
> >> +     /*
> >> +      * else no need to do anything since HW will immediately compare
> >> +      * the new threshold and generate interrupt accordingly
> >> +      */
> >> +
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +     return count;
> >> +}
> >> +
> >> +static ssize_t show_update_rate(struct device *dev,
> >> +                     struct device_attribute *devattr, char *buf)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     u32                     temp = 0, ret = 0;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     if (!temp_sensor->clk_rate) {
> >> +             dev_err(dev, "clk_rate is NULL\n");
> >> +             ret = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_counter);
> >> +     temp = (temp & temp_sensor->registers->counter_mask) >>
> >> +                     __ffs(temp_sensor->registers->counter_mask);
> >
> >        temp &= ??
> >
> >> +     temp = temp * 1000 / (temp_sensor->clk_rate);
> >
> >        temp *= ??
> 
> Need to multiply the temp with 1000 before dividing.
> temp *= evaluates the RHS first and then multiplies LHS.

temp *= 1000;
temp /= clk_rate;

> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +     if (!ret)
> >> +             return sprintf(buf, "%d\n", temp);
> >> +     else
> >> +             return ret;
> >> +}
> >> +
> >> +static ssize_t set_update_rate(struct device *dev,
> >> +                            struct device_attribute *devattr,
> >> +                            const char *buf, size_t count)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     u32                     reg_val;
> >> +     long                    val;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     if (strict_strtol(buf, 10, &val)) {
> >> +             count = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     val *= temp_sensor->clk_rate / 1000;
> >> +     reg_val = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_counter);
> >> +
> >> +     reg_val &= ~(temp_sensor->registers->counter_mask);
> >> +     reg_val |= val;
> >> +     omap_temp_sensor_writel(temp_sensor, reg_val,
> >> +                     temp_sensor->registers->bgap_counter);
> >> +
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +     return count;
> >> +}
> >> +
> >> +static int omap_temp_sensor_read_temp(struct device *dev,
> >> +                                   struct device_attribute *devattr,
> >> +                                   char *buf)
> >> +{
> >> +     struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev);
> >> +     int                     temp, ret = 0;
> >> +
> >> +     mutex_lock(&temp_sensor->sensor_mutex);
> >> +
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +             temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp &= temp_sensor->registers->bgap_dtemp_mask;
> >> +
> >> +     if (!temp_sensor->is_efuse_valid)
> >> +             dev_err(dev, "Invalid EFUSE, Non-trimmed BGAP, Temp not accurate\n");
> >> +
> >> +     /* look up for temperature in the table and return the temperature */
> >> +     if (temp < OMAP_ADC_START_VALUE || temp > OMAP_ADC_END_VALUE) {
> >> +             dev_err(dev, "invalid adc code reported %d", temp);
> >> +             ret = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     temp = adc_to_temp[temp - OMAP_ADC_START_VALUE];
> >> +
> >> +out:
> >> +     mutex_unlock(&temp_sensor->sensor_mutex);
> >> +     if (!ret)
> >> +             return sprintf(buf, "%d\n", temp);
> >> +     else
> >> +             return ret;
> >> +}
> >> +
> >> +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, omap_temp_sensor_read_temp,
> >> +                       NULL, 0);
> >> +static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
> >> +                       set_temp_max, 0);
> >> +static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, show_temp_max_hyst,
> >> +                       set_temp_max_hyst, 0);
> >> +static SENSOR_DEVICE_ATTR(update_rate, S_IWUSR | S_IRUGO, show_update_rate,
> >> +                       set_update_rate, 0);
> >> +
> >> +static struct attribute *omap_temp_sensor_attributes[] = {
> >> +     &sensor_dev_attr_temp1_input.dev_attr.attr,
> >> +     &sensor_dev_attr_temp1_max.dev_attr.attr,
> >> +     &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
> >> +     &sensor_dev_attr_update_rate.dev_attr.attr,
> >> +     NULL
> >> +};
> >> +
> >> +static const struct attribute_group omap_temp_sensor_group = {
> >> +     .attrs = omap_temp_sensor_attributes,
> >> +};
> >> +
> >> +static int omap_temp_sensor_clk_enable(struct omap_temp_sensor *temp_sensor)
> >> +{
> >> +     u32 ret = 0, temp;
> >> +
> >> +     if (temp_sensor->clk_on) {
> >> +             dev_err(temp_sensor->hwmon_dev, "clock already on\n");
> >> +             goto out;
> >> +     }
> >> +
> >> +     ret = pm_runtime_get_sync(temp_sensor->hwmon_dev);
> >> +     if (ret < 0) {
> >> +             dev_err(temp_sensor->hwmon_dev, "get sync failed\n");
> >> +             ret = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp &= ~(temp_sensor->registers->bgap_tempsoff_mask);
> >> +     /* BGAP_TEMPSOFF should be reset to 0 */
> >> +     omap_temp_sensor_writel(temp_sensor, temp,
> >> +                             temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp_sensor->clk_on = 1;
> >
> > why isn't pm_runtime_get_sync() enough ??
> 
> This is the programming sequence indicated. BGAP_TEMPSOFF should be set
> to 0 to enable the temperature sensor.

why isn't this done as part of your runtime_resume() function ??

> >> +out:
> >> +     return ret;
> >> +}
> >> +
> >> +static int omap_temp_sensor_clk_disable(struct omap_temp_sensor *temp_sensor)
> >> +{
> >> +     u32 temp, ret = 0;
> >> +     unsigned long timeout;
> >> +
> >> +     if (!temp_sensor->clk_on) {
> >> +             dev_err(temp_sensor->hwmon_dev, "clock already off\n");
> >> +             goto out;
> >> +     }
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp |= temp_sensor->registers->bgap_tempsoff_mask;
> >> +
> >> +     /* BGAP_TEMPSOFF should be set to 1 before gating clock */
> >> +     omap_temp_sensor_writel(temp_sensor, temp,
> >> +                     temp_sensor->registers->temp_sensor_ctrl);
> >> +     temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_status);
> >> +     timeout = jiffies + msecs_to_jiffies(5);
> >> +
> >> +     /* wait till the clean stop bit is set or till the timeout exppires */
> >> +     while (!(temp | temp_sensor->registers->status_clean_stop_mask) &&
> >> +             !(time_after(jiffies, timeout))) {
> >> +             temp = omap_temp_sensor_readl(temp_sensor,
> >> +                     temp_sensor->registers->bgap_status);
> >> +             usleep_range(500, 2000);
> >> +     }
> >> +
> >> +     if (time_after(jiffies, timeout))
> >> +             dev_err(temp_sensor->hwmon_dev, "Clean stop bit not set\n");
> >> +     /* Gate the clock */
> >> +     ret = pm_runtime_put_sync(temp_sensor->hwmon_dev);
> >> +     if (ret < 0) {
> >> +             dev_err(temp_sensor->hwmon_dev, "put sync failed\n");
> >> +             ret = -EINVAL;
> >> +             goto out;
> >> +     }
> >> +     temp_sensor->clk_on = 0;
> >> +out:
> >> +     return ret;
> >> +}

add a blank line here.

-- 
balbi