Hi Keerthy, On Wed, Aug 31, 2011 at 7:25 PM, Keerthy <j-keerthy@xxxxxx> wrote: > The device file adds the device support for OMAP4 > on die temperature sensor. > > Signed-off-by: Keerthy <j-keerthy@xxxxxx> > Cc: tony@xxxxxxxxxxx > --- > arch/arm/mach-omap2/Makefile | 1 + > arch/arm/mach-omap2/temp_sensor_device.c | 188 ++++++++++++++++++++++++++++++ > arch/arm/plat-omap/Kconfig | 12 ++ > 3 files changed, 201 insertions(+), 0 deletions(-) > create mode 100644 arch/arm/mach-omap2/temp_sensor_device.c > > diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile > index 2d5d981..5812fb4 100644 > --- a/arch/arm/mach-omap2/Makefile > +++ b/arch/arm/mach-omap2/Makefile > @@ -18,6 +18,7 @@ obj-$(CONFIG_ARCH_OMAP4) += prm44xx.o $(hwmod-common) > > obj-$(CONFIG_OMAP_MCBSP) += mcbsp.o > > +obj-$(CONFIG_OMAP_TEMP_SENSOR) += temp_sensor_device.o > obj-$(CONFIG_TWL4030_CORE) += omap_twl.o > > # SMP support ONLY available for OMAP4 > diff --git a/arch/arm/mach-omap2/temp_sensor_device.c b/arch/arm/mach-omap2/temp_sensor_device.c > new file mode 100644 > index 0000000..12d6789 > --- /dev/null > +++ b/arch/arm/mach-omap2/temp_sensor_device.c > @@ -0,0 +1,188 @@ > +/* > + * OMAP on die Temperature sensor device file > + * > + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ > + * Author: J Keerthy <j-keerthy@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/delay.h> > +#include <linux/slab.h> > +#include <linux/io.h> > +#include <linux/mutex.h> > +#include <linux/idr.h> > +#include <plat/omap_device.h> > +#include "pm.h" > +#include <plat/temperature_sensor.h> > + > + > +int omap_temp_sensor_device_idle(struct omap_device *od) > +{ > + struct omap_temp_sensor_registers *registers; > + struct resource *mem; > + void __iomem *phy_base; > + unsigned long timeout; > + u32 ret = 0, temp; > + > + mem = platform_get_resource(&od->pdev, IORESOURCE_MEM, 0); > + if (!mem) { > + dev_err(&od->pdev.dev, "no mem resource\n"); > + ret = -EINVAL; > + goto plat_res_err; > + } > + > + phy_base = ioremap(mem->start, resource_size(mem)); > + > + if (!phy_base) { > + dev_err(&od->pdev.dev, "ioremap failed\n"); > + ret = -ENOMEM; > + goto plat_res_err; > + } > + > + if (!strcmp(od->hwmods[0]->dev_attr, "mpu")) > + registers = &omap_mpu_temp_sensor_registers; > + > + temp = __raw_readl(phy_base + registers->temp_sensor_ctrl); > + temp |= registers->bgap_tempsoff_mask; > + > + /* BGAP_TEMPSOFF should be set to 1 before gating clock */ > + __raw_writel(temp, phy_base + registers->temp_sensor_ctrl); > + temp = __raw_readl(phy_base + registers->bgap_status); > + timeout = jiffies + msecs_to_jiffies(5); > + > + /* wait till the clean stop bit is set or till the timeout expires */ > + while (!(temp | registers->status_clean_stop_mask) && > + !(time_after(jiffies, timeout))) { > + temp = __raw_readl(phy_base + registers->bgap_status); > + usleep_range(500, 2000); > + } > + > + if (time_after(jiffies, timeout)) > + dev_err(&od->pdev.dev, "Clean stop bit not set\n"); > + > + ret = omap_device_idle_hwmods(od); > + iounmap(phy_base); > +plat_res_err: > + return ret; > +} > + > +int omap_temp_sensor_device_activate(struct omap_device *od) > +{ > + struct omap_temp_sensor_registers *registers; > + struct resource *mem; > + void __iomem *phy_base; > + u32 ret = 0, temp; > + > + ret = omap_device_enable_hwmods(od); > + if (ret < 0) > + return ret; > + mem = platform_get_resource(&od->pdev, IORESOURCE_MEM, 0); > + if (!mem) { > + dev_err(&od->pdev.dev, "no mem resource\n"); > + return -EINVAL; > + } > + > + phy_base = ioremap(mem->start, resource_size(mem)); > + if (!phy_base) { > + dev_err(&od->pdev.dev, "ioremap failed\n"); > + ret = -ENOMEM; > + goto plat_res_err; > + } > + > + if (!strcmp(od->hwmods[0]->dev_attr, "mpu")) > + registers = &omap_mpu_temp_sensor_registers; > + > + temp = __raw_readl(phy_base + registers->temp_sensor_ctrl); > + temp &= ~(registers->bgap_tempsoff_mask); > + /* BGAP_TEMPSOFF should be reset to 0 */ > + __raw_writel(temp, > + phy_base + registers->temp_sensor_ctrl); > + iounmap(phy_base); > + > +plat_res_err: > + return ret; > +} I do not think it is a good thing to ioremap and iounmap the resource registers every time you need to access the device. That should be gone in init/deinit functions instead. Regards, Jean > + > +static struct omap_device_pm_latency omap_temp_sensor_latency[] = { > + { > + .deactivate_func = omap_temp_sensor_device_idle, > + .activate_func = omap_temp_sensor_device_activate, > + .flags = OMAP_DEVICE_LATENCY_AUTO_ADJUST, > + } > +}; > + > +static DEFINE_IDR(temp_sensor_device_idr); > + > +static int temp_sensor_dev_init(struct omap_hwmod *oh, void *user) > +{ > + struct omap_temp_sensor_pdata *temp_sensor_pdata; > + struct omap_device *od; > + struct omap_temp_sensor_dev_attr *temp_sensor_dev_attr; > + int ret = 0; > + int num; > + > + temp_sensor_pdata = > + kzalloc(sizeof(*temp_sensor_pdata), GFP_KERNEL); > + if (!temp_sensor_pdata) { > + dev_err(&oh->od->pdev.dev, > + "Unable to allocate memory for temp sensor pdata\n"); > + return -ENOMEM; > + } > + > + ret = idr_pre_get(&temp_sensor_device_idr, GFP_KERNEL); > + if (ret < 0) > + goto fail_id; > + ret = idr_get_new(&temp_sensor_device_idr, temp_sensor_pdata, &num); > + if (ret < 0) > + goto fail_id; > + > + temp_sensor_dev_attr = oh->dev_attr; > + if (!strcmp(temp_sensor_dev_attr->name, "mpu")) { > + temp_sensor_pdata->registers = &omap_mpu_temp_sensor_registers; > + } else { > + dev_warn(&oh->od->pdev.dev, "Invalid device attribute\n"); > + ret = -EINVAL; > + goto fail_id; > + } > + > + od = omap_device_build("omap_temp_sensor", num, > + oh, temp_sensor_pdata, sizeof(*temp_sensor_pdata), > + omap_temp_sensor_latency, > + ARRAY_SIZE(omap_temp_sensor_latency), 0); > + > + if (IS_ERR(od)) { > + dev_warn(&oh->od->pdev.dev, > + "Could not build omap_device for %s\n", oh->name); > + ret = PTR_ERR(od); > + } > + > +fail_id: > + kfree(temp_sensor_pdata); > + > + return ret; > +} > + > +int __init omap_devinit_temp_sensor(void) > +{ > + if (!cpu_is_omap446x()) > + return 0; > + > + return omap_hwmod_for_each_by_class("temperature_sensor", > + temp_sensor_dev_init, NULL); > +} > + > +arch_initcall(omap_devinit_temp_sensor); > diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig > index 6e6735f..8fd8e80 100644 > --- a/arch/arm/plat-omap/Kconfig > +++ b/arch/arm/plat-omap/Kconfig > @@ -115,6 +115,18 @@ config OMAP_MCBSP > Say Y here if you want support for the OMAP Multichannel > Buffered Serial Port. > > +config OMAP_TEMP_SENSOR > + bool "OMAP Temp Sensor Support" > + depends on ARCH_OMAP > + default n > + help > + Say Y here if you want support for the temp sensor > + on OMAP4460. > + > + This provides the temperature of the MPU > + subsystem. Only one instance of on die temperature > + sensor is present. > + > config OMAP_MBOX_FWK > tristate "Mailbox framework support" > depends on ARCH_OMAP > -- > 1.7.0.4 > > -- > 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 > -- 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
