The system control module has several components. On die temperature is a part of system control module. The system control module driver registers the temperature sensor as a client. A hwmon driver for temperature sensor to route the temperature and the thresholds to the user space.
The system control module driver patch depends on the following series found here: http://comments.gmane.org/gmane.linux.ports.arm.omap/64436 Signed-off-by: Keerthy <[email protected]> Cc:[email protected] --- drivers/mfd/Kconfig | 9 + drivers/mfd/Makefile | 2 +- drivers/mfd/omap4460plus_scm.c | 581 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 591 insertions(+), 1 deletions(-) create mode 100644 drivers/mfd/omap4460plus_scm.c Index: linux-omap-2.6/drivers/mfd/Kconfig =================================================================== --- linux-omap-2.6.orig/drivers/mfd/Kconfig 2011-09-22 18:35:25.636575640 +0530 +++ linux-omap-2.6/drivers/mfd/Kconfig 2011-09-22 18:35:43.412576517 +0530 @@ -212,6 +212,15 @@ and other features that are often used in portable devices like cell phones and PDAs. +config OMAP4460PLUS_SCM + bool "Texas Instruments OMAP4460 System control module" + depends on ARCH_OMAP && OMAP_SCM_DEV + help + If you say yes here you get support for the Texas Instruments + OMAP4460 system control module. This includes support for + on die temperature sensor which is a part of System control + module. + config TWL4030_CORE bool "Texas Instruments TWL4030/TWL5030/TWL6030/TPS659x0 Support" depends on I2C=y && GENERIC_HARDIRQS Index: linux-omap-2.6/drivers/mfd/Makefile =================================================================== --- linux-omap-2.6.orig/drivers/mfd/Makefile 2011-09-22 18:35:25.604576115 +0530 +++ linux-omap-2.6/drivers/mfd/Makefile 2011-09-22 18:35:43.416576975 +0530 @@ -42,7 +42,7 @@ obj-$(CONFIG_MFD_TPS65912_I2C) += tps65912-i2c.o obj-$(CONFIG_MFD_TPS65912_SPI) += tps65912-spi.o obj-$(CONFIG_MENELAUS) += menelaus.o - +obj-$(CONFIG_OMAP4460PLUS_SCM) += omap4460plus_scm.o obj-$(CONFIG_TWL4030_CORE) += twl-core.o twl4030-irq.o twl6030-irq.o obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o obj-$(CONFIG_TWL4030_POWER) += twl4030-power.o Index: linux-omap-2.6/drivers/mfd/omap4460plus_scm.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux-omap-2.6/drivers/mfd/omap4460plus_scm.c 2011-09-22 18:53:05.132583900 +0530 @@ -0,0 +1,581 @@ +/* + * OMAP4 system control module driver file + * + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ + * Author: J Keerthy <[email protected]> + * Author: Moiz Sonasath <[email protected]> + * + * 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/platform_device.h> +#include <plat/omap_device.h> +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/err.h> +#include <linux/types.h> +#include <linux/mutex.h> +#include <linux/delay.h> +#include <plat/scm.h> + +#define TSHUT_HOT 920 /* 122 deg C */ +#define TSHUT_COLD 866 /* 100 deg C */ +#define T_HOT 800 /* 73 deg C */ +#define T_COLD 795 /* 71 deg C */ +#define MAX_FREQ 2000000 +#define MIN_FREQ 1000000 +#define MIN_TEMP -40000 +#define MAX_TEMP 123000 +#define HYST_VAL 5000 + +static u32 omap4460plus_scm_readl(struct scm + *scm_ptr, u32 reg) +{ + return __raw_readl(scm_ptr->phy_base + reg); +} + +static void omap4460plus_scm_writel(struct scm *scm_ptr, u32 val, u32 reg) +{ + __raw_writel(val, scm_ptr->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 high, low, mid; + + if (temp < adc_to_temp[0] || + temp > adc_to_temp[OMAP_ADC_END_VALUE - OMAP_ADC_START_VALUE]) + return -EINVAL; + + high = OMAP_ADC_END_VALUE - OMAP_ADC_START_VALUE; + low = 0; + mid = (high + low) / 2; + + while (low < high) { + if (temp < adc_to_temp[mid]) + high = mid - 1; + else + low = mid + 1; + mid = (low + high) / 2; + } + + return OMAP_ADC_START_VALUE + low; +} + +static void temp_sensor_unmask_interrupts(struct scm *scm_ptr, int id, + u32 t_hot, u32 t_cold) +{ + struct omap_temp_sensor_registers *tsr; + u32 temp, reg_val; + + /* Read the current on die temperature */ + tsr = scm_ptr->registers[id]; + temp = omap4460plus_scm_readl(scm_ptr, tsr->temp_sensor_ctrl); + temp &= tsr->bgap_dtemp_mask; + + reg_val = omap4460plus_scm_readl(scm_ptr, tsr->bgap_mask_ctrl); + if (temp < t_hot) + reg_val |= tsr->mask_hot_mask; + else + reg_val &= ~tsr->mask_hot_mask; + + if (t_cold < temp) + reg_val |= tsr->mask_cold_mask; + else + reg_val &= ~tsr->mask_cold_mask; + + omap4460plus_scm_writel(scm_ptr, reg_val, tsr->bgap_mask_ctrl); +} + +static int add_hyst(int adc_val, int hyst_val) +{ + int temp = adc_to_temp_conversion(adc_val); + + temp += hyst_val; + + return temp_to_adc_conversion(temp); +} + +static void temp_sensor_configure_thot(struct scm *scm_ptr, int id, int t_hot) +{ + int cold, thresh_val; + struct omap_temp_sensor_registers *tsr; + u32 reg_val; + + tsr = scm_ptr->registers[id]; + /* obtain the T cold value */ + thresh_val = omap4460plus_scm_readl(scm_ptr, tsr->bgap_threshold); + cold = (thresh_val & tsr->threshold_tcold_mask) >> + __ffs(tsr->threshold_tcold_mask); + + if (t_hot <= cold) { + /* change the t_cold to t_hot - 5000 millidegrees */ + cold = add_hyst(t_hot, -HYST_VAL); + /* write the new t_cold value */ + reg_val = thresh_val & (~tsr->threshold_tcold_mask); + reg_val |= cold << __ffs(tsr->threshold_tcold_mask); + omap4460plus_scm_writel(scm_ptr, reg_val, + tsr->bgap_threshold); + thresh_val = reg_val; + } + + /* write the new t_hot value */ + reg_val = thresh_val & ~tsr->threshold_thot_mask; + reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)); + omap4460plus_scm_writel(scm_ptr, reg_val, tsr->bgap_threshold); + temp_sensor_unmask_interrupts(scm_ptr, id, t_hot, cold); +} + +static void temp_sensor_configure_tcold(struct scm *scm_ptr, int id, int t_cold) +{ + int hot, thresh_val; + u32 reg_val; + struct omap_temp_sensor_registers *tsr; + + tsr = scm_ptr->registers[id]; + /* obtain the T cold value */ + thresh_val = omap4460plus_scm_readl(scm_ptr, tsr->bgap_threshold); + hot = (thresh_val & tsr->threshold_thot_mask) >> + __ffs(tsr->threshold_thot_mask); + + if (t_cold >= hot) { + /* change the t_hot to t_cold + 5000 millidegrees */ + hot = add_hyst(t_cold, HYST_VAL); + /* write the new t_hot value */ + reg_val = thresh_val & (~tsr->threshold_thot_mask); + reg_val |= hot << __ffs(tsr->threshold_thot_mask); + omap4460plus_scm_writel(scm_ptr, reg_val, + tsr->bgap_threshold); + thresh_val = reg_val; + } + + /* write the new t_cold value */ + reg_val = thresh_val & ~tsr->threshold_tcold_mask; + reg_val |= (t_cold << __ffs(tsr->threshold_tcold_mask)); + omap4460plus_scm_writel(scm_ptr, reg_val, tsr->bgap_threshold); + temp_sensor_unmask_interrupts(scm_ptr, id, hot, t_cold); +} + +static void configure_temp_sensor_counter(struct scm *scm_ptr, int id, + u32 counter) +{ + u32 val; + + val = omap4460plus_scm_readl(scm_ptr, + scm_ptr->registers[id]->bgap_counter); + val &= ~scm_ptr->registers[id]->counter_mask; + val |= counter << __ffs(scm_ptr->registers[id]->counter_mask); + omap4460plus_scm_writel(scm_ptr, val, + scm_ptr->registers[id]->bgap_counter); + +} + +int omap4460plus_scm_show_temp_max(struct scm *scm_ptr, int id) +{ + struct omap_temp_sensor_registers *tsr; + int temp; + + tsr = scm_ptr->registers[id]; + temp = omap4460plus_scm_readl(scm_ptr, tsr->bgap_threshold); + temp = (temp & tsr->threshold_thot_mask) + >> __ffs(tsr->threshold_thot_mask); + temp = adc_to_temp_conversion(temp); + + return temp; +} +EXPORT_SYMBOL(omap4460plus_scm_show_temp_max); + +int omap4460plus_scm_set_temp_max(struct scm *scm_ptr, int id, int val) +{ + struct omap_temp_sensor_registers *tsr; + u32 t_hot; + tsr = scm_ptr->registers[id]; + + if (val < MIN_TEMP - HYST_VAL) + return -EINVAL; + t_hot = temp_to_adc_conversion(val); + if (t_hot < 0) + return t_hot; + + mutex_lock(&scm_ptr->scm_mutex); + temp_sensor_configure_thot(scm_ptr, id, t_hot); + mutex_unlock(&scm_ptr->scm_mutex); + + return 0; +} +EXPORT_SYMBOL(omap4460plus_scm_set_temp_max); + +int omap4460plus_scm_show_temp_max_hyst(struct scm *scm_ptr, int id) +{ + struct omap_temp_sensor_registers *tsr; + int temp; + + tsr = scm_ptr->registers[id]; + temp = omap4460plus_scm_readl(scm_ptr, tsr->bgap_threshold); + temp = (temp & tsr->threshold_tcold_mask) + >> __ffs(tsr->threshold_tcold_mask); + temp = adc_to_temp_conversion(temp); + + return temp; +} +EXPORT_SYMBOL(omap4460plus_scm_show_temp_max_hyst); + +int omap4460plus_scm_set_temp_max_hyst(struct scm *scm_ptr, + int id, int val) +{ + struct omap_temp_sensor_registers *tsr; + u32 t_cold; + tsr = scm_ptr->registers[id]; + + if (val < MIN_TEMP + HYST_VAL) + return -EINVAL; + t_cold = temp_to_adc_conversion(val); + if (t_cold < 0) + return t_cold; + + mutex_lock(&scm_ptr->scm_mutex); + temp_sensor_configure_tcold(scm_ptr, id, t_cold); + mutex_unlock(&scm_ptr->scm_mutex); + + return 0; +} +EXPORT_SYMBOL(omap4460plus_scm_set_temp_max_hyst); + +void omap4460plus_scm_set_update_interval(struct scm *scm_ptr, + u32 interval, int id) +{ + interval = interval * scm_ptr->clk_rate / 1000; + mutex_lock(&scm_ptr->scm_mutex); + configure_temp_sensor_counter(scm_ptr, id, interval); + mutex_unlock(&scm_ptr->scm_mutex); +} +EXPORT_SYMBOL(omap4460plus_scm_set_update_interval); + +int omap4460plus_scm_show_update_interval(struct scm *scm_ptr, int id) +{ + struct omap_temp_sensor_registers *tsr; + int time; + tsr = scm_ptr->registers[id]; + + time = omap4460plus_scm_readl(scm_ptr, tsr->bgap_counter); + time = (time & tsr->counter_mask) >> __ffs(tsr->counter_mask); + time = time * 1000 / scm_ptr->clk_rate; + + return time; +} +EXPORT_SYMBOL(omap4460plus_scm_show_update_interval); + +int omap4460plus_scm_read_temp(struct scm *scm_ptr, int id) +{ + struct omap_temp_sensor_registers *tsr; + int temp; + tsr = scm_ptr->registers[id]; + + temp = omap4460plus_scm_readl(scm_ptr, tsr->temp_sensor_ctrl); + temp &= tsr->bgap_dtemp_mask; + + /* look up for temperature in the table and return the temperature */ + if (temp < OMAP_ADC_START_VALUE || temp > OMAP_ADC_END_VALUE) + return -EIO; + + return adc_to_temp_conversion(temp); +} +EXPORT_SYMBOL(omap4460plus_scm_read_temp); + +/** + * enable_continuous_mode() - One time enbaling of continuous conversion mode + * @scm_ptr - pointer to scm instance + */ +static void enable_continuous_mode(struct scm *scm_ptr) +{ + u32 val; + int i; + + for (i = 0; i < scm_ptr->cnt; i++) { + val = omap4460plus_scm_readl(scm_ptr, + scm_ptr->registers[i]-> + bgap_mode_ctrl); + + val |= 1 << __ffs(scm_ptr->registers[i]->mode_ctrl_mask); + + omap4460plus_scm_writel(scm_ptr, val, + scm_ptr->registers[i]->bgap_mode_ctrl); + } +} + +static irqreturn_t talert_irq_handler(int irq, void *data) +{ + struct scm *scm_ptr; + int t_hot = 0, t_cold, temp, i; + struct omap_temp_sensor_registers *tsr; + + scm_ptr = data; + mutex_lock(&scm_ptr->scm_mutex); + /* Read the status of t_hot */ + for (i = 0; i < scm_ptr->cnt; i++) { + tsr = scm_ptr->registers[i]; + t_hot = omap4460plus_scm_readl(scm_ptr, tsr->bgap_status) + & tsr->status_hot_mask; + + /* Read the status of t_cold */ + t_cold = omap4460plus_scm_readl(scm_ptr, tsr->bgap_status) + & tsr->status_cold_mask; + + temp = omap4460plus_scm_readl(scm_ptr, tsr->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 &= ~tsr->mask_hot_mask; + temp |= tsr->mask_cold_mask; + } else if (t_cold) { + temp &= ~tsr->mask_cold_mask; + temp |= tsr->mask_hot_mask; + } + + omap4460plus_scm_writel(scm_ptr, temp, tsr->bgap_mask_ctrl); + + if (t_hot || t_cold) + /* kobject_uvent to user space threshold crossed */ + kobject_uevent(&scm_ptr->tsh_ptr[i].pdev->dev.kobj, + KOBJ_CHANGE); + } + + mutex_unlock(&scm_ptr->scm_mutex); + + return IRQ_HANDLED; +} + +void omap4460plus_scm_client_dev_register(struct temp_sensor_hwmon *tsh_ptr, + int i, const char *name) +{ + int ret; + + tsh_ptr->pdev = platform_device_alloc(name, i); + if (tsh_ptr->pdev == NULL) { + dev_err(tsh_ptr->scm_ptr->dev, "Failed to allocate %s\n", name); + return; + } + + tsh_ptr->pdev->dev.parent = tsh_ptr->scm_ptr->dev; + platform_set_drvdata(tsh_ptr->pdev, tsh_ptr); + ret = platform_device_add(tsh_ptr->pdev); + if (ret != 0) { + dev_err(tsh_ptr->scm_ptr->dev, "Failed to register %s: %d\n", + name, ret); + platform_device_put(tsh_ptr->pdev); + tsh_ptr->pdev = NULL; + } +} + +static int __devinit omap4460plus_scm_probe(struct platform_device *pdev) +{ + struct omap4460plus_scm_pdata *pdata = pdev->dev.platform_data; + struct scm *scm_ptr; + struct resource *mem; + int ret = 0, i; + int clk_rate; + u32 max_freq, min_freq; + + if (!pdata) { + dev_err(&pdev->dev, "platform data missing\n"); + return -EINVAL; + } + + scm_ptr = kzalloc(sizeof(*scm_ptr), GFP_KERNEL); + if (!scm_ptr) { + dev_err(&pdev->dev, "Memory allocation failed\n"); + return -ENOMEM; + } + + scm_ptr->tsh_ptr = kzalloc(sizeof(*scm_ptr->tsh_ptr) * pdata->cnt, + GFP_KERNEL); + if (!scm_ptr) { + dev_err(&pdev->dev, "Memory allocation failed for tsh\n"); + kfree(scm_ptr); + return -ENOMEM; + } + + mutex_init(&scm_ptr->scm_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; + } + + scm_ptr->irq = platform_get_irq_byname(pdev, "thermal_alert"); + if (scm_ptr->irq < 0) { + dev_err(&pdev->dev, "get_irq_byname failed\n"); + ret = scm_ptr->irq; + goto plat_res_err; + } + + scm_ptr->phy_base = ioremap(mem->start, resource_size(mem)); + if (!scm_ptr->phy_base) { + dev_err(&pdev->dev, "ioremap failed\n"); + ret = -ENOMEM; + goto plat_res_err; + } + + scm_ptr->registers = pdata->registers; + scm_ptr->name = pdata->name; + scm_ptr->dev = &pdev->dev; + scm_ptr->cnt = pdata->cnt; + + if (pdata->max_freq && pdata->min_freq) { + max_freq = pdata->max_freq; + min_freq = pdata->min_freq; + } else { + max_freq = MAX_FREQ; + min_freq = MIN_FREQ; + } + + /* + * check if the efuse has a non-zero value if not + * it is an untrimmed sample and the temperatures + * may not be accurate + */ + if (omap4460plus_scm_readl(scm_ptr, scm_ptr->registers[0]->bgap_efuse)) + dev_info(&pdev->dev, + "Invalid EFUSE, Non-trimmed BGAP, Temp not accurate\n"); + dev_set_drvdata(&pdev->dev, scm_ptr); + scm_ptr->fclock = clk_get(&pdev->dev, "fck"); + scm_ptr->div_clk = clk_get(&pdev->dev, "div_ck"); + clk_enable(scm_ptr->fclock); + + clk_rate = clk_round_rate(scm_ptr->div_clk, max_freq); + if (clk_rate < min_freq || clk_rate == 0xffffffff) { + ret = -ENODEV; + goto clken_err; + } + + ret = clk_set_rate(scm_ptr->div_clk, clk_rate); + if (ret) { + dev_err(&pdev->dev, "Cannot set clock rate\n"); + goto clken_err; + } + + scm_ptr->clk_rate = clk_rate; + + enable_continuous_mode(scm_ptr); + /* 1 clk cycle */ + for (i = 0; i < pdata->cnt; i++) + configure_temp_sensor_counter(scm_ptr, i, 1); + + /* Wait till the first conversion is done wait for at least 1ms */ + usleep_range(1000, 2000); + + /* Set 2 seconds time as default counter */ + for (i = 0; i < pdata->cnt; i++) + configure_temp_sensor_counter(scm_ptr, i, + scm_ptr->clk_rate * 2); + for (i = 0; i < pdata->cnt; i++) { + scm_ptr->tsh_ptr[i].scm_ptr = scm_ptr; + scm_ptr->tsh_ptr[i].name = scm_ptr->name[i]; + omap4460plus_scm_client_dev_register(&(scm_ptr->tsh_ptr[i]), + i, "temp_sensor_hwmon"); + temp_sensor_configure_thot(scm_ptr, i, T_HOT); + temp_sensor_configure_tcold(scm_ptr, i, T_COLD); + } + + ret = request_threaded_irq(scm_ptr->irq, NULL, + talert_irq_handler, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, "TAlert", + scm_ptr); + if (ret) { + dev_err(&pdev->dev, "Request threaded irq failed.\n"); + goto req_irq_err; + } + + mutex_lock(&scm_ptr->scm_mutex); + + for (i = 0; i < pdata->cnt; i++) + temp_sensor_unmask_interrupts(scm_ptr, i, OMAP_ADC_END_VALUE, + OMAP_ADC_START_VALUE); + + mutex_unlock(&scm_ptr->scm_mutex); + + return 0; + +req_irq_err: + clk_disable(scm_ptr->fclock); +clken_err: + clk_put(scm_ptr->fclock); + clk_put(scm_ptr->div_clk); + iounmap(scm_ptr->phy_base); +plat_res_err: + dev_set_drvdata(&pdev->dev, NULL); + mutex_destroy(&scm_ptr->scm_mutex); + kfree(scm_ptr->tsh_ptr); + kfree(scm_ptr); + + return ret; +} + +static int __devexit omap4460plus_scm_remove(struct platform_device *pdev) +{ + struct scm *scm_ptr = platform_get_drvdata(pdev); + + free_irq(scm_ptr->irq, scm_ptr); + clk_disable(scm_ptr->fclock); + clk_put(scm_ptr->fclock); + clk_put(scm_ptr->div_clk); + iounmap(scm_ptr->phy_base); + dev_set_drvdata(&pdev->dev, NULL); + mutex_destroy(&scm_ptr->scm_mutex); + kfree(scm_ptr); + + return 0; +} + +static struct platform_driver omap4460plus_scm_driver = { + .probe = omap4460plus_scm_probe, + .remove = omap4460plus_scm_remove, + .driver = { + .name = "omap4460plus_scm", + }, +}; + +int __init omap4460plus_scm_init(void) +{ + return platform_driver_register(&omap4460plus_scm_driver); +} + +module_init(omap4460plus_scm_init); + +static void __exit omap4460plus_scm_exit(void) +{ + platform_driver_unregister(&omap4460plus_scm_driver); +} + +module_exit(omap4460plus_scm_exit); + +MODULE_DESCRIPTION("OMAP446X plus system control module Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); +MODULE_AUTHOR("J Keerthy <[email protected]>"); -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
