On Fri, Aug 19, 2011 at 11:34 AM, J, KEERTHY <j-keerthy@xxxxxx> wrote: > On Fri, Aug 19, 2011 at 7:43 AM, Guenter Roeck > <guenter.roeck@xxxxxxxxxxxx> wrote: >> On Thu, Aug 18, 2011 at 06:52:15AM -0400, 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@xxxxxx> >>> Cc: Jean Delvare <khali@xxxxxxxxxxxx> >>> Cc: Guenter Roeck <guenter.roeck@xxxxxxxxxxxx> >>> Cc: lm-sensors@xxxxxxxxxxxxxx >> >> High level review: >> >> - too much and too broad mutex locking. show functions should not need locks at all, >> set functions only while data is written into registers and into platform data. > > Ok. I will clean this. Even the show function might read an inconsistent value without a mutex lock if the registers were written using set function was preempted. There is a necessity for mutex locking even in show function. > >> - driver is quite noisy. There should definitely not be any log messages >> if a set parameter is wrong. Show functions already return an error value >> to the user; a log message indicating the error again just creates noise. >> For one boolean set during probe (is_efuse_valid), each subsequent show results >> in a log message if it is false. Some errors result in multiple log messages. > > A user tries to set an invalid temperature threshold. The user should > be notified about this. The invalid temperature will not be set. The user > should not be allowed to set an invalid temperature. It is to inform > the user about precisely the problem with the parameter. > > In some of the samples the bandgap is not trimmed and hence > temperature reported will be wrong. So every time a user tries to read > he is alerted that the temperatures are not accurate. > >> - Wrong use of EINVAL throughout the driver (EINVAL is "Invalid Argument") > > Ok. I will correct this. > >> - excessive ( ) > > Ok. > >> - linear search through a sorted array is very expensive. Consider using a binary search. > > Yes. I will implement binary search. > >> - temp_to_adc_conversion return code (error if negative) is not checked properly. > > Ok. I will add checks. > >> >> I am sure there are other problems, but those are difficult to find with all the noise >> above. >> >> Guenter >> >>> --- >>> Documentation/hwmon/omap_temp_sensor | 27 + >>> drivers/hwmon/Kconfig | 11 + >>> drivers/hwmon/Makefile | 1 + >>> drivers/hwmon/omap_temp_sensor.c | 918 ++++++++++++++++++++++++++++++++++ >>> 4 files changed, 957 insertions(+), 0 deletions(-) >>> create mode 100644 Documentation/hwmon/omap_temp_sensor >>> create mode 100644 drivers/hwmon/omap_temp_sensor.c >>> >>> diff --git a/Documentation/hwmon/omap_temp_sensor b/Documentation/hwmon/omap_temp_sensor >>> new file mode 100644 >>> index 0000000..e01a6d6 >>> --- /dev/null >>> +++ b/Documentation/hwmon/omap_temp_sensor >>> @@ -0,0 +1,27 @@ >>> +Kernel driver omap_temp_sensor >>> +============================== >>> + >>> +Supported chips: >>> + * Texas Instruments OMAP4460 >>> + Prefix: 'omap_temp_sensor' >>> + Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp102.html >>> + >>> +Author: >>> + J Keerthy <j-keerthy@xxxxxx> >>> + >>> +Description >>> +----------- >>> + >>> +The Texas Instruments OMAP4 family of chips have a bandgap temperature sensor. >>> +The temperature sensor feature is used to convert the temperature of the device >>> +into a decimal value coded on 10 bits. An internal ADC is used for conversion. >>> +The recommended operating temperatures must be in the range -40 degree Celsius >>> +to 123 degree celsius for standard conversion. >>> +The thresholds are programmable and upon crossing the thresholds an interrupt >>> +is generated. The OMAP temperature sensor has a programmable update rate in >>> +milli seconds. >>> +(Currently the driver programs a default of 2000 milli seconds). >>> + >>> +The driver provides the common sysfs-interface for temperatures (see >>> +Documentation/hwmon/sysfs-interface under Temperatures). >>> + >>> 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..586a361 >>> --- /dev/null >>> +++ b/drivers/hwmon/omap_temp_sensor.c >>> @@ -0,0 +1,918 @@ >>> +/* >>> + * OMAP4 Temperature sensor driver file >>> + * >>> + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ >>> + * Author: J Keerthy <j-keerthy@xxxxxx> >>> + * Author: Moiz Sonasath <m-sonasath@xxxxxx> >>> + * >>> + * 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> >>> +#include <linux/io.h> >>> +#include <linux/slab.h> >>> +#include <linux/init.h> >>> +#include <plat/omap_device.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 <linux/delay.h> >>> +#include <plat/temperature_sensor.h> >>> + >>> +#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"); >>> + mutex_unlock(&temp_sensor->sensor_mutex); >>> + return -EINVAL; >>> + } >>> + >>> + temp = adc_to_temp_conversion(temp); >>> + 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"); >>> + mutex_unlock(&temp_sensor->sensor_mutex); >>> + return -EINVAL; >>> + } >>> + >>> + temp = adc_to_temp_conversion(temp); >>> + 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 * 1000 / (temp_sensor->clk_rate); >>> + >>> +out: >>> + mutex_unlock(&temp_sensor->sensor_mutex); >>> + if (!ret) >>> + return sprintf(buf, "%d\n", temp); >>> + >>> + 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); >>> + >>> + 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; >>> + >>> + 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"); >>> + goto out; >>> + } >>> + >>> + temp_sensor->clk_on = 1; >>> + >>> +out: >>> + return ret; >>> +} >>> + >>> +static int omap_temp_sensor_clk_disable(struct omap_temp_sensor *temp_sensor) >>> +{ >>> + u32 ret = 0; >>> + >>> + if (!temp_sensor->clk_on) { >>> + dev_err(temp_sensor->hwmon_dev, "clock already off\n"); >>> + goto out; >>> + } >>> + >>> + /* 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"); >>> + goto out; >>> + } >>> + temp_sensor->clk_on = 0; >>> + >>> +out: >>> + return ret; >>> +} >>> + >>> +static irqreturn_t omap_talert_irq_handler(int irq, void *data) >>> +{ >>> + struct omap_temp_sensor *temp_sensor; >>> + int t_hot, t_cold, temp; >>> + >>> + temp_sensor = data; >>> + mutex_lock(&temp_sensor->sensor_mutex); >>> + >>> + /* Read the status of t_hot */ >>> + t_hot = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_status) >>> + & temp_sensor->registers->status_hot_mask; >>> + >>> + /* Read the status of t_cold */ >>> + t_cold = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_status) >>> + & temp_sensor->registers->status_cold_mask; >>> + >>> + temp = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + /* >>> + * One TALERT interrupt: Two sources >>> + * If the interrupt is due to t_hot then mask t_hot and >>> + * and unmask t_cold else mask t_cold and unmask t_hot >>> + */ >>> + if (t_hot) { >>> + temp &= ~(temp_sensor->registers->mask_hot_mask); >>> + temp |= temp_sensor->registers->mask_cold_mask; >>> + } else if (t_cold) { >>> + temp &= ~(temp_sensor->registers->mask_cold_mask); >>> + temp |= temp_sensor->registers->mask_hot_mask; >>> + } >>> + >>> + omap_temp_sensor_writel(temp_sensor, temp, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + >>> + /* kobject_uvent to user space telling thermal threshold crossed */ >>> + kobject_uevent(&temp_sensor->hwmon_dev->kobj, KOBJ_CHANGE); >>> + >>> + mutex_unlock(&temp_sensor->sensor_mutex); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static int __devinit omap_temp_sensor_probe(struct platform_device *pdev) >>> +{ >>> + struct omap_temp_sensor_pdata *pdata = pdev->dev.platform_data; >>> + struct omap_temp_sensor *temp_sensor; >>> + struct resource *mem; >>> + int ret = 0; >>> + int val, clk_rate; >>> + >>> + if (!pdata) { >>> + dev_err(&pdev->dev, "platform data missing\n"); >>> + return -EINVAL; >>> + } >>> + >>> + temp_sensor = kzalloc(sizeof(*temp_sensor), GFP_KERNEL); >>> + if (!temp_sensor) >>> + return -ENOMEM; >>> + >>> + mutex_init(&temp_sensor->sensor_mutex); >>> + >>> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); >>> + if (!mem) { >>> + dev_err(&pdev->dev, "no mem resource\n"); >>> + ret = -ENOMEM; >>> + goto plat_res_err; >>> + } >>> + >>> + temp_sensor->irq = platform_get_irq_byname(pdev, "thermal_alert"); >>> + if (temp_sensor->irq < 0) { >>> + dev_err(&pdev->dev, "get_irq_byname failed\n"); >>> + ret = temp_sensor->irq; >>> + goto plat_res_err; >>> + } >>> + >>> + temp_sensor->phy_base = ioremap(mem->start, resource_size(mem)); >>> + temp_sensor->clock = NULL; >>> + temp_sensor->registers = pdata->registers; >>> + temp_sensor->hwmon_dev = &pdev->dev; >>> + >>> + pm_runtime_enable(&pdev->dev); >>> + pm_runtime_irq_safe(&pdev->dev); >>> + >>> + /* >>> + * check if the efuse has a non-zero value if not >>> + * it is an untrimmed sample and the temperatures >>> + * may not be accurate >>> + */ >>> + >>> + if (omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_efuse)) >>> + temp_sensor->is_efuse_valid = 1; >>> + >>> + platform_set_drvdata(pdev, temp_sensor); >>> + dev_set_drvdata(&pdev->dev, temp_sensor); >>> + temp_sensor->clock = clk_get(temp_sensor->hwmon_dev, "fck"); >>> + if (IS_ERR(temp_sensor->clock)) { >>> + ret = PTR_ERR(temp_sensor->clock); >>> + dev_err(temp_sensor->hwmon_dev, >>> + "unable to get fclk: %d\n", ret); >>> + ret = -EINVAL; >>> + goto plat_res_err; >>> + } >>> + >>> + ret = omap_temp_sensor_clk_enable(temp_sensor); >>> + if (ret) { >>> + dev_err(&pdev->dev, "Cannot enable temp sensor\n"); >>> + goto clken_err; >>> + } >>> + >>> + clk_rate = clk_round_rate(temp_sensor->clock, 2000000); >>> + if (clk_rate < 1000000 || clk_rate == 0xffffffff) { >>> + dev_err(&pdev->dev, "Error round rate\n"); >>> + ret = -EINVAL; >>> + goto clken_err; >>> + } >>> + >>> + ret = clk_set_rate(temp_sensor->clock, clk_rate); >>> + if (ret) { >>> + dev_err(&pdev->dev, "Cannot set clock rate\n"); >>> + goto clken_err; >>> + } >>> + >>> + temp_sensor->clk_rate = clk_rate; >>> + omap_enable_continuous_mode(temp_sensor, 1); >>> + omap_configure_temp_sensor_thresholds(temp_sensor); >>> + /* 1 ms */ >>> + omap_configure_temp_sensor_counter(temp_sensor, 1); >>> + >>> + /* Wait till the first conversion is done wait for at least 1ms */ >>> + usleep_range(1000, 2000); >>> + >>> + /* Read the temperature once due to hw issue*/ >>> + omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->temp_sensor_ctrl); >>> + >>> + /* Set 2 seconds time as default counter */ >>> + omap_configure_temp_sensor_counter(temp_sensor, >>> + temp_sensor->clk_rate * 2); >>> + >>> + temp_sensor->hwmon_dev = hwmon_device_register(&pdev->dev); >>> + if (IS_ERR(temp_sensor->hwmon_dev)) { >>> + dev_err(&pdev->dev, "hwmon_device_register failed.\n"); >>> + ret = PTR_ERR(temp_sensor->hwmon_dev); >>> + goto hwmon_reg_err; >>> + } >>> + >>> + ret = sysfs_create_group(&pdev->dev.kobj, >>> + &omap_temp_sensor_group); >>> + if (ret) { >>> + dev_err(&pdev->dev, "could not create sysfs files\n"); >>> + goto sysfs_create_err; >>> + } >>> + >>> + kobject_uevent(&temp_sensor->hwmon_dev->kobj, KOBJ_ADD); >>> + >>> + ret = request_threaded_irq(temp_sensor->irq, NULL, >>> + omap_talert_irq_handler, IRQF_TRIGGER_RISING | IRQF_ONESHOT, >>> + "temp_sensor", temp_sensor); >>> + if (ret) { >>> + dev_err(&pdev->dev, "Request threaded irq failed.\n"); >>> + goto req_irq_err; >>> + } >>> + >>> + /* unmask the T_COLD and unmask T_HOT at init */ >>> + val = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + val |= temp_sensor->registers->mask_cold_mask >>> + | temp_sensor->registers->mask_hot_mask; >>> + >>> + omap_temp_sensor_writel(temp_sensor, val, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + >>> + return 0; >>> + >>> +req_irq_err: >>> + kobject_uevent(&temp_sensor->hwmon_dev->kobj, KOBJ_REMOVE); >>> + sysfs_remove_group(&temp_sensor->hwmon_dev->kobj, >>> + &omap_temp_sensor_group); >>> +sysfs_create_err: >>> + hwmon_device_unregister(&pdev->dev); >>> +hwmon_reg_err: >>> + omap_temp_sensor_clk_disable(temp_sensor); >>> +clken_err: >>> + clk_put(temp_sensor->clock); >>> +plat_res_err: >>> + mutex_destroy(&temp_sensor->sensor_mutex); >>> + kfree(temp_sensor); >>> + return ret; >>> +} >>> + >>> +static int __devexit omap_temp_sensor_remove(struct platform_device *pdev) >>> +{ >>> + struct omap_temp_sensor *temp_sensor = platform_get_drvdata(pdev); >>> + >>> + hwmon_device_unregister(&pdev->dev); >>> + kobject_uevent(&temp_sensor->hwmon_dev->kobj, KOBJ_REMOVE); >>> + sysfs_remove_group(&temp_sensor->hwmon_dev->kobj, >>> + &omap_temp_sensor_group); >>> + omap_temp_sensor_clk_disable(temp_sensor); >>> + clk_put(temp_sensor->clock); >>> + platform_set_drvdata(pdev, NULL); >>> + free_irq(temp_sensor->irq, temp_sensor); >>> + mutex_destroy(&temp_sensor->sensor_mutex); >>> + kfree(temp_sensor); >>> + >>> + return 0; >>> +} >>> + >>> +#ifdef CONFIG_PM >>> +static void omap_temp_sensor_save_ctxt(struct omap_temp_sensor *temp_sensor) >>> +{ >>> + temp_sensor->temp_sensor_ctrl = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->temp_sensor_ctrl); >>> + temp_sensor->bg_ctrl = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + temp_sensor->bg_counter = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_counter); >>> + temp_sensor->bg_threshold = omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->bgap_threshold); >>> + temp_sensor->temp_sensor_tshut_threshold = >>> + omap_temp_sensor_readl(temp_sensor, >>> + temp_sensor->registers->thsut_threshold); >>> +} >>> + >>> +static void omap_temp_sensor_restore_ctxt(struct omap_temp_sensor *temp_sensor) >>> +{ >>> + omap_temp_sensor_writel(temp_sensor, >>> + temp_sensor->temp_sensor_ctrl, >>> + temp_sensor->registers->temp_sensor_ctrl); >>> + omap_temp_sensor_writel(temp_sensor, >>> + temp_sensor->bg_ctrl, >>> + temp_sensor->registers->bgap_mask_ctrl); >>> + omap_temp_sensor_writel(temp_sensor, >>> + temp_sensor->bg_counter, >>> + temp_sensor->registers->bgap_counter); >>> + omap_temp_sensor_writel(temp_sensor, >>> + temp_sensor->bg_threshold, >>> + temp_sensor->registers->bgap_threshold); >>> + omap_temp_sensor_writel(temp_sensor, >>> + temp_sensor->temp_sensor_tshut_threshold, >>> + temp_sensor->registers->thsut_threshold); >>> +} >>> + >>> +static int omap_temp_sensor_suspend(struct device *dev) >>> +{ >>> + struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev); >>> + >>> + omap_temp_sensor_save_ctxt(temp_sensor); >>> + >>> + return 0; >>> +} >>> + >>> +static int omap_temp_sensor_resume(struct device *dev) >>> +{ >>> + struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev); >>> + >>> + omap_temp_sensor_restore_ctxt(temp_sensor); >>> + >>> + return 0; >>> +} >>> + >>> +static int omap_temp_sensor_runtime_suspend(struct device *dev) >>> +{ >>> + struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev); >>> + >>> + omap_temp_sensor_save_ctxt(temp_sensor); >>> + >>> + return 0; >>> +} >>> + >>> +static int omap_temp_sensor_runtime_resume(struct device *dev) >>> +{ >>> + static int context_loss_count; >>> + int temp; >>> + struct omap_temp_sensor *temp_sensor = dev_get_drvdata(dev); >>> + >>> + temp = omap_device_get_context_loss_count(to_platform_device(dev)); >>> + >>> + if (temp != context_loss_count && context_loss_count != 0) >>> + omap_temp_sensor_restore_ctxt(temp_sensor); >>> + >>> + context_loss_count = temp; >>> + >>> + return 0; >>> +} >>> + >>> +static const struct dev_pm_ops omap_temp_sensor_dev_pm_ops = { >>> + .suspend = omap_temp_sensor_suspend, >>> + .resume = omap_temp_sensor_resume, >>> + .runtime_suspend = omap_temp_sensor_runtime_suspend, >>> + .runtime_resume = omap_temp_sensor_runtime_resume, >>> +}; >>> + >>> +#endif >>> + >>> +static struct platform_driver omap_temp_sensor_driver = { >>> + .probe = omap_temp_sensor_probe, >>> + .remove = omap_temp_sensor_remove, >>> + .driver = { >>> + .name = "omap_temp_sensor", >>> +#ifdef CONFIG_PM >>> + .pm = &omap_temp_sensor_dev_pm_ops, >>> +#endif >>> + }, >>> +}; >>> + >>> +int __init omap_temp_sensor_init(void) >>> +{ >>> + return platform_driver_register(&omap_temp_sensor_driver); >>> +} >>> +module_init(omap_temp_sensor_init); >>> + >>> +static void __exit omap_temp_sensor_exit(void) >>> +{ >>> + platform_driver_unregister(&omap_temp_sensor_driver); >>> +} >>> +module_exit(omap_temp_sensor_exit); >>> + >>> +MODULE_DESCRIPTION("OMAP446X temperature sensor Driver"); >>> +MODULE_LICENSE("GPL"); >>> +MODULE_ALIAS("platform:" DRIVER_NAME); >>> +MODULE_AUTHOR("J Keerthy <j-keerthy@xxxxxx>"); >>> -- >>> 1.7.0.4 >>> >> > > > > -- > Regards and Thanks, > Keerthy > -- Regards and Thanks, Keerthy -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
