lkml.org 
[lkml]   [2010]   [Jun]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [lm-sensors] [PATCH v2 23/26] hwmon: Add JZ4740 ADC driver
    On Sat, 19 Jun 2010 07:08:28 +0200, Lars-Peter Clausen wrote:
    > This patch adds support for reading the ADCIN pin of ADC unit on JZ4740 SoCs.
    >
    > Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
    > Cc: Jonathan Cameron <kernel@jic23.retrosnub.co.uk>
    > Cc: lm-sensors@lm-sensors.org
    >
    > ---
    > Changes since v1
    > - Move ADC core access synchronizing from the HWMON driver to a MFD driver. The
    > ADC driver now only reads the adcin value.
    > ---
    > drivers/hwmon/Kconfig | 11 +++
    > drivers/hwmon/Makefile | 1 +
    > drivers/hwmon/jz4740-hwmon.c | 206 ++++++++++++++++++++++++++++++++++++++++++
    > 3 files changed, 218 insertions(+), 0 deletions(-)
    > create mode 100644 drivers/hwmon/jz4740-hwmon.c
    >
    > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
    > index 569082c..51fc2f6 100644
    > --- a/drivers/hwmon/Kconfig
    > +++ b/drivers/hwmon/Kconfig
    > @@ -446,6 +446,17 @@ config SENSORS_IT87
    > This driver can also be built as a module. If so, the module
    > will be called it87.
    >
    > +config SENSORS_JZ4740
    > + tristate "Ingenic JZ4740 SoC ADC driver"
    > + depends on MACH_JZ4740
    > + help
    > + If you say yes here you get support for the Ingenic JZ4740 SoC ADC core.
    > + It is required for the JZ4740 battery and touchscreen driver and is used
    > + to synchronize access to the adc module between those two.
    > +
    > + This driver can also be build as a module. If so, the module will be
    > + called jz4740-adc.
    > +
    > config SENSORS_LM63
    > tristate "National Semiconductor LM63 and LM64"
    > depends on I2C
    > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
    > index bca0d45..dffbdff 100644
    > --- a/drivers/hwmon/Makefile
    > +++ b/drivers/hwmon/Makefile
    > @@ -55,6 +55,7 @@ obj-$(CONFIG_SENSORS_I5K_AMB) += i5k_amb.o
    > obj-$(CONFIG_SENSORS_IBMAEM) += ibmaem.o
    > obj-$(CONFIG_SENSORS_IBMPEX) += ibmpex.o
    > obj-$(CONFIG_SENSORS_IT87) += it87.o
    > +obj-$(CONFIG_SENSORS_JZ4740) += jz4740-hwmon.o
    > obj-$(CONFIG_SENSORS_K8TEMP) += k8temp.o
    > obj-$(CONFIG_SENSORS_K10TEMP) += k10temp.o
    > obj-$(CONFIG_SENSORS_LIS3LV02D) += lis3lv02d.o hp_accel.o
    > diff --git a/drivers/hwmon/jz4740-hwmon.c b/drivers/hwmon/jz4740-hwmon.c
    > new file mode 100644
    > index 0000000..f53d15e
    > --- /dev/null
    > +++ b/drivers/hwmon/jz4740-hwmon.c
    > @@ -0,0 +1,206 @@
    > +/*
    > + * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
    > + * JZ4740 SoC HWMON driver
    > + *
    > + * This program is free software; you can redistribute it and/or modify it
    > + * under the terms of the GNU General Public License as published by the
    > + * Free Software Foundation; either version 2 of the License, or (at your
    > + * option) any later version.
    > + *
    > + * 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.,
    > + * 675 Mass Ave, Cambridge, MA 02139, USA.
    > + *
    > + */
    > +
    > +#include <linux/err.h>
    > +#include <linux/interrupt.h>
    > +#include <linux/kernel.h>
    > +#include <linux/module.h>
    > +#include <linux/mutex.h>
    > +#include <linux/platform_device.h>
    > +#include <linux/slab.h>
    > +
    > +#include <linux/mfd/core.h>
    > +
    > +#include <linux/hwmon.h>
    > +#include <linux/hwmon-sysfs.h>
    > +
    > +struct jz4740_hwmon {
    > + struct resource *mem;
    > + void __iomem *base;
    > +
    > + int irq;
    > +
    > + struct mfd_cell *cell;
    > + struct device *hwmon;
    > +
    > + struct completion read_completion;
    > +
    > + struct mutex lock;
    > +};
    > +
    > +static irqreturn_t jz4740_hwmon_irq(int irq, void *data)
    > +{
    > + struct jz4740_hwmon *hwmon = data;
    > +
    > + complete(&hwmon->read_completion);
    > + return IRQ_HANDLED;
    > +}
    > +
    > +static ssize_t jz4740_hwmon_read_adcin(struct device *dev,
    > + struct device_attribute *dev_attr, char *buf)
    > +{
    > + struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
    > + unsigned long t;
    > + uint16_t val;
    > + int ret;
    > +
    > + mutex_lock(&hwmon->lock);
    > +
    > + INIT_COMPLETION(hwmon->read_completion);
    > +
    > + enable_irq(hwmon->irq);
    > + hwmon->cell->enable(to_platform_device(dev));
    > +
    > + t = wait_for_completion_interruptible_timeout(&hwmon->read_completion, HZ);
    > +
    > + if (t > 0) {
    > + val = readw(hwmon->base);
    > + ret = sprintf(buf, "%d\n", val);

    What is the unit of "val"? The value returned to userspace must be in
    mV, so in most cases a simple conversion is needed in the driver.

    > + } else {
    > + ret = t ? t : -ETIMEDOUT;
    > + }
    > +
    > + hwmon->cell->disable(to_platform_device(dev));
    > + disable_irq(hwmon->irq);
    > +
    > + mutex_unlock(&hwmon->lock);
    > +
    > + return ret;
    > +}
    > +
    > +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL, 0);
    > +
    > +static int __devinit jz4740_hwmon_probe(struct platform_device *pdev)
    > +{
    > + int ret;
    > + struct jz4740_hwmon *hwmon;
    > +
    > + hwmon = kmalloc(sizeof(*hwmon), GFP_KERNEL);
    > +
    > + hwmon->cell = pdev->dev.platform_data;
    > +
    > + hwmon->irq = platform_get_irq(pdev, 0);
    > + if (hwmon->irq < 0) {
    > + ret = hwmon->irq;
    > + dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
    > + goto err_free;
    > + }
    > +
    > + hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    > + if (!hwmon->mem) {
    > + ret = -ENOENT;
    > + dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
    > + goto err_free;
    > + }
    > +
    > + hwmon->mem = request_mem_region(hwmon->mem->start,
    > + resource_size(hwmon->mem), pdev->name);
    > + if (!hwmon->mem) {
    > + ret = -EBUSY;
    > + dev_err(&pdev->dev, "Failed to request mmio memory region\n");
    > + goto err_free;
    > + }
    > +
    > + hwmon->base = ioremap_nocache(hwmon->mem->start, resource_size(hwmon->mem));
    > + if (!hwmon->base) {
    > + ret = -EBUSY;
    > + dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
    > + goto err_release_mem_region;
    > + }
    > +
    > + init_completion(&hwmon->read_completion);
    > + mutex_init(&hwmon->lock);
    > +
    > + platform_set_drvdata(pdev, hwmon);
    > +
    > + ret = request_irq(hwmon->irq, jz4740_hwmon_irq, 0, pdev->name, hwmon);
    > + if (ret) {
    > + dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
    > + goto err_iounmap;
    > + }
    > + disable_irq(hwmon->irq);
    > +
    > + ret = device_create_file(&pdev->dev, &sensor_dev_attr_in0_input.dev_attr);
    > + if (ret) {
    > + dev_err(&pdev->dev, "Failed to create sysfs file: %d\n", ret);
    > + goto err_free_irq;
    > + }

    You must create a name attribute as well, if you want your device to be
    supported by libsensors.

    > +
    > + hwmon->hwmon = hwmon_device_register(&pdev->dev);
    > + if (IS_ERR(hwmon->hwmon)) {
    > + ret = PTR_ERR(hwmon->hwmon);
    > + goto err_remove_file;
    > + }
    > +
    > + return 0;
    > +
    > +err_remove_file:
    > + device_remove_file(&pdev->dev, &sensor_dev_attr_in0_input.dev_attr);
    > +err_free_irq:
    > + free_irq(hwmon->irq, hwmon);
    > +err_iounmap:
    > + platform_set_drvdata(pdev, NULL);
    > + iounmap(hwmon->base);
    > +err_release_mem_region:
    > + release_mem_region(hwmon->mem->start, resource_size(hwmon->mem));
    > +err_free:
    > + kfree(hwmon);
    > +
    > + return ret;
    > +}
    > +
    > +static int __devexit jz4740_hwmon_remove(struct platform_device *pdev)
    > +{
    > + struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev);
    > +
    > + hwmon_device_unregister(hwmon->hwmon);
    > + device_remove_file(&pdev->dev, &sensor_dev_attr_in0_input.dev_attr);
    > +
    > + free_irq(hwmon->irq, hwmon);
    > +
    > + iounmap(hwmon->base);
    > + release_mem_region(hwmon->mem->start, resource_size(hwmon->mem));
    > +
    > + platform_set_drvdata(pdev, NULL);
    > + kfree(hwmon);
    > +
    > + return 0;
    > +}
    > +
    > +struct platform_driver jz4740_hwmon_driver = {
    > + .probe = jz4740_hwmon_probe,
    > + .remove = __devexit_p(jz4740_hwmon_remove),
    > + .driver = {
    > + .name = "jz4740-hwmon",
    > + .owner = THIS_MODULE,
    > + },
    > +};
    > +
    > +static int __init jz4740_hwmon_init(void)
    > +{
    > + return platform_driver_register(&jz4740_hwmon_driver);
    > +}
    > +module_init(jz4740_hwmon_init);
    > +
    > +static void __exit jz4740_hwmon_exit(void)
    > +{
    > + platform_driver_unregister(&jz4740_hwmon_driver);
    > +}
    > +module_exit(jz4740_hwmon_exit);
    > +
    > +MODULE_DESCRIPTION("JZ4740 SoC HWMON driver");
    > +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
    > +MODULE_LICENSE("GPL");
    > +MODULE_ALIAS("platform:jz4740-hwmon");


    --
    Jean Delvare


    \
     
     \ /
      Last update: 2010-06-19 10:39    [W:0.041 / U:63.504 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site