> 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);
