Re: [PATCH] mfd: Add support for TI LMP92001

From: Peter Meerwald-Stadler
Date: Tue Aug 22 2017 - 03:37:28 EST



> From: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
>
> TI LMP92001 Analog System Monitor and Controller

some minor comments, not a full review

> 8-bit GPIOs.
> 12 DACs with 12-bit resolution.
> The GPIOs and DACs are shared port function with Cy function pin to
> take control the pin suddenly from external hardware.
> DAC's referance voltage selectable for Internal/External.

typo, reference (here and below)

> 16 + 1 ADCs with 12-bit resolution.
> Built-in internal Temperature Sensor on channel 17.
> Windows Comparator Function is supported on channel 1-3 and 9-11 for

Window (here and below)

> monitoring with interrupt signal (pending to implement for interrupt).
> ADC's referance voltage selectable for Internal/External.

reference

> Signed-off-by: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> ---
> Documentation/ABI/testing/sysfs-bus-iio-lmp920001 | 92 ++++
> .../devicetree/bindings/gpio/gpio-lmp92001.txt | 22 +
> .../bindings/iio/adc/ti-lmp92001-adc.txt | 21 +
> .../bindings/iio/dac/ti-lmp92001-dac.txt | 35 ++
> drivers/gpio/Kconfig | 7 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-lmp92001.c | 209 +++++++++
> drivers/iio/adc/Kconfig | 10 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/lmp92001-adc.c | 500 +++++++++++++++++++++
> drivers/iio/dac/Kconfig | 9 +
> drivers/iio/dac/Makefile | 1 +
> drivers/iio/dac/lmp92001-dac.c | 390 ++++++++++++++++
> drivers/mfd/Kconfig | 12 +
> drivers/mfd/Makefile | 4 +
> drivers/mfd/lmp92001-core.c | 308 +++++++++++++
> drivers/mfd/lmp92001-debug.c | 67 +++
> drivers/mfd/lmp92001-i2c.c | 215 +++++++++
> include/linux/mfd/lmp92001/core.h | 119 +++++
> include/linux/mfd/lmp92001/debug.h | 28 ++
> 20 files changed, 2051 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-lmp920001
> create mode 100644 Documentation/devicetree/bindings/gpio/gpio-lmp92001.txt
> create mode 100644 Documentation/devicetree/bindings/iio/adc/ti-lmp92001-adc.txt
> create mode 100644 Documentation/devicetree/bindings/iio/dac/ti-lmp92001-dac.txt
> create mode 100644 drivers/gpio/gpio-lmp92001.c
> create mode 100644 drivers/iio/adc/lmp92001-adc.c
> create mode 100644 drivers/iio/dac/lmp92001-dac.c
> create mode 100644 drivers/mfd/lmp92001-core.c
> create mode 100644 drivers/mfd/lmp92001-debug.c
> create mode 100644 drivers/mfd/lmp92001-i2c.c
> create mode 100644 include/linux/mfd/lmp92001/core.h
> create mode 100644 include/linux/mfd/lmp92001/debug.h
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-lmp920001 b/Documentation/ABI/testing/sysfs-bus-iio-lmp920001
> new file mode 100644
> index 0000000..bd4e733
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-lmp920001
> @@ -0,0 +1,92 @@
> +What: /sys/bus/iio/devices/iio:deviceX/gang
> +Date: August 2016
> +KernelVersion: 4.1.15

update? (here and below)

> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + Controls the association of analog output channels OUTx with
> + asynchronous control inputs Cy for DAC.
> + Can be either:
> + - "0"
> + - "1"
> +
> + Cy to OUTx Assignment
> + ----------------------------------
> + | Cy | CDAC:GANG=0 | CDAC:GANG=1 |
> + ----------------------------------
> + | C1 | OUT[1:4] | OUT[1:3] |
> + ----------------------------------
> + | C2 | OUT[5:6] | OUT[4:6] |
> + ----------------------------------
> + | C3 | OUT[7:8] | OUT[7:9] |
> + ----------------------------------
> + | C4 | OUT[9:12] | OUT[10:12] |
> + ----------------------------------
> +
> +What: /sys/bus/iio/devices/iio:deviceX/outx
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + The pin output mode for DAC.
> + Can be either:
> + - "hiz" = High impedance state.
> + - "dac" = DAC output.
> + - "0" = Drive it to low.
> + - "1" = Drive it to high.
> +
> +What: /sys/bus/iio/devices/iio:deviceX/vref
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is voltage referance source for DACs.
> + Can be either:
> + - "external"
> + - "internal"
> +
> +What: /sys/devices/socX/soc/XXXXXXX.aips-bus/XXXXXXX.i2c/i2c-X/X-00XX/lmp92001-adc.X.auto/iio:deviceX/en
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is ADC Conversion Enable for each channel.
> + Can be either:
> + - "enable"
> + - "disable"
> +
> +What: /sys/devices/socX/soc/XXXXXXX.aips-bus/XXXXXXX.i2c/i2c-X/X-00XX/lmp92001-adc.X.auto/iio:deviceX/mode
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is conversion mode for all of ADCs.
> + Can be either:
> + - "continuous" = Continuously conversion all the time.
> + - "single-shot" = Once time conversion and stop.

One time

> +
> +What: /sys/devices/socX/soc/XXXXXXX.aips-bus/XXXXXXX.i2c/i2c-X/X-00XX/lmp92001-adc.X.auto/iio:deviceX/vref
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is voltage referance source for ADCs.
> + Can be either:
> + - "external"
> + - "internal"
> +
> +What: /sys/devices/socX/soc/XXXXXXX.aips-bus/XXXXXXX.i2c/i2c-X/X-00XX/lmp92001-adc.X.auto/iio:deviceX/events/in_voltageX_thresh_{falling|rising}_en
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is ADC's Windows Comparator Function enable for falling and rising.
> + Supported channels are 1-3 and 9-11.
> +
> +What: /sys/devices/socX/soc/XXXXXXX.aips-bus/XXXXXXX.i2c/i2c-X/X-00XX/lmp92001-adc.X.auto/iio:deviceX/events/in_voltageX_thresh_{falling|rising}_value
> +Date: August 2016
> +KernelVersion: 4.1.15
> +Contact: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> +Description:
> + This is ADC's Windows Comparator Function value for falling and rising.
> + Supported channels are 1-3 and 9-11.
> + The possible range is 0 - 2047.
> diff --git a/Documentation/devicetree/bindings/gpio/gpio-lmp92001.txt b/Documentation/devicetree/bindings/gpio/gpio-lmp92001.txt
> new file mode 100644
> index 0000000..c68784e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/gpio-lmp92001.txt
> @@ -0,0 +1,22 @@
> +* Texas Instruments' LMP92001 GPIOs
> +
> +Required properties:
> + - compatible: Must be set to "ti,lmp92001-gpio".
> + - reg: i2c chip address for the device.
> + - gpio-controller: Marks the device node as a gpio controller.
> + - #gpio-cells : Should be two. The first cell is the pin number and the
> + second cell is used to specify the gpio polarity:
> + 0 = Active high
> + 1 = Active low
> +
> +Example:
> +lmp92001@20 {
> + compatible = "ti,lmp92001";
> + reg = <0x20>;
> +
> + lmp92001_gpio: lmp92001-gpio {
> + compatible = "ti,lmp92001-gpio";
> + gpio-controller;
> + #gpio-cells = <2>;
> + };
> +};
> diff --git a/Documentation/devicetree/bindings/iio/adc/ti-lmp92001-adc.txt b/Documentation/devicetree/bindings/iio/adc/ti-lmp92001-adc.txt
> new file mode 100644
> index 0000000..34d7809
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/ti-lmp92001-adc.txt
> @@ -0,0 +1,21 @@
> +* Texas Instruments' LMP92001 ADCs
> +
> +Required properties:
> + - compatible: Must be set to "ti,lmp92001-adc".
> + - reg: i2c chip address for the device.
> + - ti,lmp92001-adc-mode: adc operation, either continuous or single-shot.
> + - ti,lmp92001-adc-mask: bit mask for which channel is enable.
> + 0 = Off
> + 1 = On
> +
> +Example:
> +lmp92001@20 {
> + compatible = "ti,lmp92001";
> + reg = <0x20>;
> +
> + lmp92001-adc {
> + compatible = "ti,lmp92001-adc";
> + ti,lmp92001-adc-mode = "continuous";
> + ti,lmp92001-adc-mask = <0x00000079>;
> + };
> +};
> \ No newline at end of file
> diff --git a/Documentation/devicetree/bindings/iio/dac/ti-lmp92001-dac.txt b/Documentation/devicetree/bindings/iio/dac/ti-lmp92001-dac.txt
> new file mode 100644
> index 0000000..882db9c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/dac/ti-lmp92001-dac.txt
> @@ -0,0 +1,35 @@
> +* Texas Instruments' LMP92001 DACs
> +
> +Required properties:
> + - compatible: Must be set to "ti,lmp92001-dac".
> + - reg: i2c chip address for the device.
> + - ti,lmp92001-dac-hiz: hi-impedance control,
> + 1 = Forces all OUT[1:12] outputs to hi-z, 0 = normal
> + - ti,lmp92001-dac-outx:
> + Cy = 0, 1 = will force associated OUTx outputs to VDD
> + Cy = 0, 0 = will force associated OUTx outputs to GND
> + - ti,lmp92001-dac-gang: What group of Cy is governed to.
> + -----------------------------------------
> + | Cy | CDAC:GANG = 0 | CDAC:GANG = 1 |
> + -----------------------------------------
> + | C1 | OUT[1:4] | OUT[1:3] |
> + -----------------------------------------
> + | C2 | OUT[5:6] | OUT[4:6] |
> + -----------------------------------------
> + | C3 | OUT[7:8] | OUT[7:9] |
> + -----------------------------------------
> + | C4 | OUT[9:12] | OUT[10:12] |
> + -----------------------------------------
> +
> +Example:
> +lmp92001@20 {
> + compatible = "ti,lmp92001";
> + reg = <0x20>;
> +
> + lmp92001-dac {
> + compatible = "ti,lmp92001-dac";
> + ti,lmp92001-dac-hiz = /bits/ 8 <0>;
> + ti,lmp92001-dac-outx = /bits/ 8 <0>;
> + ti,lmp92001-dac-gang = /bits/ 8 <0>;
> + };
> +};
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 461d6fc..5962ea0 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -948,6 +948,13 @@ config GPIO_KEMPLD
> This driver can also be built as a module. If so, the module will be
> called gpio-kempld.
>
> +config GPIO_LMP92001
> + tristate "LMP92001 GPIOs"
> + depends on MFD_LMP92001
> + help
> + Say yes here to access the GPIO signals of TI LMP92001 Analog System
> + Monitor and Controller.
> +
> config GPIO_LP3943
> tristate "TI/National Semiconductor LP3943 GPIO expander"
> depends on MFD_LP3943
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index a9fda6c..560d59c 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -62,6 +62,7 @@ obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o
> obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o
> obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o
> obj-$(CONFIG_GPIO_INTEL_MID) += gpio-intel-mid.o
> +obj-$(CONFIG_GPIO_LMP92001) += gpio-lmp92001.o
> obj-$(CONFIG_GPIO_LOONGSON) += gpio-loongson.o
> obj-$(CONFIG_GPIO_LP3943) += gpio-lp3943.o
> obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o
> diff --git a/drivers/gpio/gpio-lmp92001.c b/drivers/gpio/gpio-lmp92001.c
> new file mode 100644
> index 0000000..b80ba4e
> --- /dev/null
> +++ b/drivers/gpio/gpio-lmp92001.c
> @@ -0,0 +1,209 @@
> +/*
> + * gpio-lmp92001.c - Support for TI LMP92001 GPIOs
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +
> +#include <linux/mfd/lmp92001/core.h>
> +
> +#define SGEN_GPI (1 << 0) /* 1 - if any bit in SGPI is set. */

1 << 0 is 1, maybe BIT(0)?

> +
> +struct lmp92001_gpio {
> + struct lmp92001 *lmp92001;
> + struct gpio_chip gpio_chip;
> +};
> +
> +static int lmp92001_gpio_get_direction(struct gpio_chip *chip, unsigned offset)

unsigned vs unsigned int

> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> + unsigned int val;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CGPO, &val);
> + if (ret < 0)
> + return ret;
> +
> + return (val >> offset) & BIT(0);
> +}
> +
> +static int lmp92001_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> +
> + return regmap_update_bits(lmp92001->regmap, LMP92001_CGPO, BIT(offset),
> + BIT(offset));
> +}
> +
> +static int lmp92001_gpio_get(struct gpio_chip *chip, unsigned offset)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> + unsigned int val, sgen;
> +
> + /*
> + * Does the GPIO input mode?
> + * Does the GPIO was set?

wording, I don't understand

> + * Reading indicated logic level.
> + * Clear indicated logic level.
> + */
> + regmap_read(lmp92001->regmap, LMP92001_CGPO, &val);
> + if ((val >> offset) & BIT(0)) {
> + regmap_read(lmp92001->regmap, LMP92001_SGEN, &sgen);
> + if (sgen & SGEN_GPI) {
> + regmap_read(lmp92001->regmap, LMP92001_SGPI, &val);
> + regmap_update_bits(lmp92001->regmap, LMP92001_CGPO,
> + 0xFF, val);
> + }
> + }
> +
> + return !!(val & BIT(offset));
> +}
> +
> +static int lmp92001_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
> + int value)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> +
> + return regmap_update_bits(lmp92001->regmap, LMP92001_CGPO, BIT(offset),
> + 0 << offset);
> +}
> +
> +static void lmp92001_gpio_set(struct gpio_chip *chip, unsigned offset,
> + int value)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> +
> + regmap_update_bits(lmp92001->regmap, LMP92001_CGPO, BIT(offset),
> + value << offset);
> +}
> +
> +#ifdef CONFIG_DEBUG_FS
> +static void lmp92001_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = gpiochip_get_data(chip);
> + struct lmp92001 *lmp92001 = lmp92001_gpio->lmp92001;
> + int i, gpio;
> + unsigned int cgpo;
> + const char *label, *dir, *logic;
> +
> + for (i = 0; i < chip->ngpio; i++) {
> + gpio = i + chip->base;
> +
> + label = gpiochip_is_requested(chip, i);
> + if (!label)
> + continue;
> +
> + regmap_read(lmp92001->regmap, LMP92001_CGPO, &cgpo);

retval is not checked here (and elsewhere)

> + if ((cgpo>>i) & BIT(0))

space around operator

> + dir = "in";
> + else
> + dir = "out";
> +
> + if (lmp92001_gpio_get(chip, i))
> + logic = "hi";
> + else
> + logic = "lo";
> +
> + seq_printf(s, " gpio-%-3d (%-20.20s) %-3.3s %-2.2s\n",
> + gpio, label, dir, logic);
> + }
> +}
> +#else
> +#define lmp92001_gpio_dbg_show NULL
> +#endif
> +
> +static struct gpio_chip lmp92001_gpio_chip = {
> + .label = "lmp92001",
> + .owner = THIS_MODULE,
> + .get_direction = lmp92001_gpio_get_direction,
> + .direction_input = lmp92001_gpio_direction_in,
> + .get = lmp92001_gpio_get,
> + .direction_output = lmp92001_gpio_direction_out,
> + .set = lmp92001_gpio_set,
> + .dbg_show = lmp92001_gpio_dbg_show,
> +};
> +
> +static int lmp92001_gpio_probe(struct platform_device *pdev)
> +{
> + struct lmp92001 *lmp92001 = dev_get_drvdata(pdev->dev.parent);
> + struct lmp92001_gpio *lmp92001_gpio;
> + int ret;
> +
> + lmp92001_gpio = devm_kzalloc(&pdev->dev, sizeof(*lmp92001_gpio),
> + GFP_KERNEL);
> + if (!lmp92001_gpio)
> + return -ENOMEM;
> +
> + lmp92001_gpio->lmp92001 = lmp92001;
> + lmp92001_gpio->gpio_chip = lmp92001_gpio_chip;
> + lmp92001_gpio->gpio_chip.ngpio = 8;
> + lmp92001_gpio->gpio_chip.parent = &pdev->dev;
> + lmp92001_gpio->gpio_chip.base = -1;
> +
> + ret = devm_gpiochip_add_data(&pdev->dev, &lmp92001_gpio->gpio_chip,
> + lmp92001_gpio);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
> + return ret;
> + }
> +
> + platform_set_drvdata(pdev, lmp92001_gpio);
> +
> + return ret;
> +}
> +
> +static int lmp92001_gpio_remove(struct platform_device *pdev)
> +{
> + struct lmp92001_gpio *lmp92001_gpio = platform_get_drvdata(pdev);
> +
> + devm_gpiochip_remove(&pdev->dev, &lmp92001_gpio->gpio_chip);
> +
> + return 0;
> +}
> +
> +static struct platform_driver lmp92001_gpio_driver = {
> + .driver.name = "lmp92001-gpio",
> + .probe = lmp92001_gpio_probe,
> + .remove = lmp92001_gpio_remove,
> +};
> +
> +static int __init lmp92001_gpio_init(void)
> +{
> + return platform_driver_register(&lmp92001_gpio_driver);
> +}
> +subsys_initcall(lmp92001_gpio_init);
> +
> +static void __exit lmp92001_gpio_exit(void)
> +{
> + platform_driver_unregister(&lmp92001_gpio_driver);
> +}
> +module_exit(lmp92001_gpio_exit);
> +
> +MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@xxxxxxxxx>");
> +MODULE_DESCRIPTION("GPIO interface for TI LMP92001");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:lmp92001-gpio");
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 614fa41..2adeba5 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -331,6 +331,16 @@ config IMX7D_ADC
> This driver can also be built as a module. If so, the module will be
> called imx7d_adc.
>
> +config LMP92001_ADC
> + tristate "TI LMP92001 ADC Driver"
> + depends on MFD_LMP92001
> + help
> + If you say yes here you get support for TI LMP92001 ADCs
> + conversion.
> +
> + This driver can also be built as a module. If so, the module will
> + be called lmp92001_adc.
> +
> config LP8788_ADC
> tristate "LP8788 ADC driver"
> depends on MFD_LP8788
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index b546736a..2ed8986 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -31,6 +31,7 @@ obj-$(CONFIG_HI8435) += hi8435.o
> obj-$(CONFIG_HX711) += hx711.o
> obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
> obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
> +obj-$(CONFIG_LMP92001_ADC) += lmp92001-adc.o
> obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
> obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o
> obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
> diff --git a/drivers/iio/adc/lmp92001-adc.c b/drivers/iio/adc/lmp92001-adc.c
> new file mode 100644
> index 0000000..8e64b51
> --- /dev/null
> +++ b/drivers/iio/adc/lmp92001-adc.c
> @@ -0,0 +1,500 @@
> +/*
> + * lmp92001-adc.c - Support for TI LMP92001 ADCs
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x and ad5064 drivers.
> + *
> + * 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/iio/iio.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/mfd/lmp92001/core.h>
> +
> +#define CGEN_STRT (1 << 0) /* Is continuous conversion all of ADCs? */

in IIO subsys, we want a prefix for all #defines, so LMP92001_CGEN_STRT
wording of comment
maybe use BIT()

> +#define CGEN_LCK (1 << 1) /* Is lock the HW register? */
> +#define CGEN_RST (1 << 7) /* Reset all registers. */
> +
> +#define CREF_AEXT (1 << 1) /* 1 - ADC external reference.
> + * 0 - ADC internal reference.
> + */
> +
> +static int lmp92001_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *channel,
> + int *val, int *val2,
> + long mask)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int code, cgen, sgen, try;
> + int ret;
> +
> + mutex_lock(&lmp92001->adc_lock);
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen);
> + if (ret < 0)
> + goto exit;
> +
> + /*
> + * Is not continuous conversion?
> + * Lock the HW registers (if needed).
> + * Triggering single-short conversion.
> + * Waiting for conversion successfully.

successful

> + */
> + if (!(cgen & CGEN_STRT)) {
> + if (!(cgen & CGEN_LCK)) {
> + ret = regmap_update_bits(lmp92001->regmap,
> + LMP92001_CGEN, CGEN_LCK, CGEN_LCK);
> + if (ret < 0)
> + goto exit;
> + }
> +
> + /* Writing any value to triggered Single-Shot conversion. */

to trigger

> + ret = regmap_write(lmp92001->regmap, LMP92001_CTRIG, 1);
> + if (ret < 0)
> + goto exit;
> +
> + /* In case of conversion is in-progress, repeat for 10 times. */
> + try = 10;
> + do {
> + ret = regmap_read(lmp92001->regmap,
> + LMP92001_SGEN, &sgen);
> + if (ret < 0)
> + goto exit;
> + } while ((sgen & CGEN_RST) && (--try > 0));
> +
> + if (!try) {
> + ret = -ETIME;
> + goto exit;
> + }
> + }
> +
> + ret = regmap_read(lmp92001->regmap, 0x1F + channel->channel, &code);
> + if (ret < 0)
> + goto exit;

could mutex_unlock() here already

> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + switch (channel->type) {
> + case IIO_VOLTAGE:
> + case IIO_TEMP:
> + *val = code;
> + ret = IIO_VAL_INT;

simplify control flow, return directly
can save many break lines...

> + goto exit;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + /* In case of no match channel info/type is return here. */
> + ret = -EINVAL;
> +
> +exit:
> + mutex_unlock(&lmp92001->adc_lock);
> +
> + return ret;
> +}
> +
> +static const struct iio_info lmp92001_info = {
> + .read_raw = lmp92001_read_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +static ssize_t lmp92001_avref_read(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cref;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CREF, &cref);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%s\n", cref & CREF_AEXT ? "external" : "internal");

maybe parenthesis, (cref & CREF_AEXT) for readability
here and below

> +}
> +
> +static ssize_t lmp92001_avref_write(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel,
> + const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cref;
> + int ret;
> +
> + if (strncmp("external", buf, 8) == 0)

why strncmp()? it should match exactly

> + cref = 2;
> + else if (strncmp("internal", buf, 8) == 0)
> + cref = 0;
> + else
> + return -EINVAL;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CREF, CREF_AEXT,
> + cref);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +static ssize_t lmp92001_enable_read(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int reg, cad;
> + int ret;
> +
> + switch (channel->channel) {
> + case 1 ... 8:
> + reg = LMP92001_CAD1;
> + break;
> + case 9 ... 16:
> + reg = LMP92001_CAD2;
> + break;
> + case 17:
> + reg = LMP92001_CAD3;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + ret = regmap_read(lmp92001->regmap, reg, &cad);
> + if (ret < 0)
> + return ret;
> +
> + if (channel->channel <= 8)
> + cad >>= channel->channel - 1;
> + else if (channel->channel > 8)
> + cad >>= channel->channel - 9;
> + else if (channel->channel > 16)
> + cad >>= channel->channel - 17;
> + else
> + return -EINVAL;
> +
> + return sprintf(buf, "%s\n", cad & BIT(0) ? "enable" : "disable");
> +}
> +
> +static ssize_t lmp92001_enable_write(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel,
> + const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int reg, enable, shif, mask;
> + int ret;
> +
> + switch (channel->channel) {
> + case 1 ... 8:
> + reg = LMP92001_CAD1;
> + shif = (channel->channel - 1);
> + break;
> + case 9 ... 16:
> + reg = LMP92001_CAD2;
> + shif = (channel->channel - 9);
> + break;
> + case 17:
> + reg = LMP92001_CAD3;
> + shif = (channel->channel - 17);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (strncmp("enable", buf, 6) == 0)
> + enable = 1;
> + else if (strncmp("disable", buf, 7) == 0)
> + enable = 0;
> + else
> + return -EINVAL;
> +
> + enable <<= shif;
> + mask = 1 << shif;
> +
> + ret = regmap_update_bits(lmp92001->regmap, reg, mask, enable);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +static ssize_t lmp92001_mode_read(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cgen;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%s\n",
> + cgen & BIT(0) ? "continuous" : "single-shot");
> +}
> +
> +static ssize_t lmp92001_mode_write(struct iio_dev *indio_dev,
> + uintptr_t private, struct iio_chan_spec const *channel,
> + const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cgen;
> + int ret;
> +
> + if (strncmp("continuous", buf, 10) == 0)

strcmp()

> + cgen = 1;
> + else if (strncmp("single-shot", buf, 11) == 0)
> + cgen = 0;
> + else
> + return -EINVAL;
> +

need mutex here?

> + /*
> + * Unlock the HW registers.
> + * Set conversion mode.
> + * Lock the HW registers.
> + */
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, 0);
> + if (ret < 0)
> + return ret;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_STRT,
> + cgen);
> + if (ret < 0)
> + return ret;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK,
> + CGEN_LCK);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +static const struct iio_chan_spec_ext_info lmp92001_ext_info[] = {
> + {
> + .name = "vref",
> + .read = lmp92001_avref_read,
> + .write = lmp92001_avref_write,
> + .shared = IIO_SHARED_BY_ALL,

indentation

> + },
> + {
> + .name = "en",
> + .read = lmp92001_enable_read,
> + .write = lmp92001_enable_write,
> + .shared = IIO_SEPARATE,
> + },
> + {
> + .name = "mode",
> + .read = lmp92001_mode_read,
> + .write = lmp92001_mode_write,
> + .shared = IIO_SHARED_BY_ALL,
> + },
> + { },
> +};
> +
> +static const struct iio_event_spec lmp92001_events[] = {
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_RISING,
> + .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
> + BIT(IIO_EV_INFO_VALUE),
> + },
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_FALLING,
> + .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
> + BIT(IIO_EV_INFO_VALUE),
> + },
> + { },
> +};
> +
> +#define LMP92001_CHAN_SPEC(_ch, _type, _event, _nevent) \
> +{ \
> + .channel = _ch, \
> + .type = _type, \
> + .indexed = 1, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .event_spec = _event, \
> + .num_event_specs = _nevent, \
> + .ext_info = lmp92001_ext_info, \
> +}
> +
> +static const struct iio_chan_spec lmp92001_adc_channels[] = {
> + LMP92001_CHAN_SPEC(1, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(2, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(3, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(4, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(5, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(6, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(7, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(8, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(9, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(10, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(11, IIO_VOLTAGE, lmp92001_events,
> + ARRAY_SIZE(lmp92001_events)),
> + LMP92001_CHAN_SPEC(12, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(13, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(14, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(15, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(16, IIO_VOLTAGE, NULL, 0),
> + LMP92001_CHAN_SPEC(17, IIO_TEMP, NULL, 0),

wondering in what unit VOLTAGE and TEMP is returned? likely need _SCALE

> +};
> +
> +static int lmp92001_adc_probe(struct platform_device *pdev)
> +{
> + struct lmp92001 *lmp92001 = dev_get_drvdata(pdev->dev.parent);
> + struct iio_dev *indio_dev;
> + struct device_node *np = pdev->dev.of_node;
> + const char *conversion;
> + unsigned int cgen = 0, cad1, cad2, cad3;
> + u32 mask;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*lmp92001));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + mutex_init(&lmp92001->adc_lock);
> +
> + iio_device_set_drvdata(indio_dev, lmp92001);
> +
> + indio_dev->name = pdev->name;
> + indio_dev->dev.parent = &pdev->dev;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->info = &lmp92001_info;
> + indio_dev->channels = lmp92001_adc_channels;
> + indio_dev->num_channels = ARRAY_SIZE(lmp92001_adc_channels);
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN,
> + CGEN_RST, CGEN_RST);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to self reset all registers\n");
> + return ret;
> + }
> +
> + /*
> + * Turn on all of them, if you are pretty sure they are must be
> + * real-time update or specify which channel is needed to be used to
> + * save conversion time for a cycle.
> + */
> + ret = of_property_read_u32(np, "ti,lmp92001-adc-mask", &mask);
> + if (ret < 0) {
> + cad1 = cad2 = cad3 = 0xFF;
> + dev_info(&pdev->dev, "turn on all of channels by default\n");
> + } else {
> + cad1 = mask & 0xFF;
> + cad2 = (mask >> 8) & 0xFF;
> + cad3 = (mask >> 16) & 0xFF;
> + }
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD1, 0xFF, cad1);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to enable/disable channels 1-8\n");
> + return ret;
> + }
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD2, 0xFF, cad2);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to enable/disable channels 9-16\n");
> + return ret;
> + }
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD3, BIT(0), cad3);
> + if (ret < 0) {
> + dev_err(&pdev->dev,
> + "failed to enable/disable channel 17 (temperature)\n");
> + return ret;
> + }
> +
> + ret = of_property_read_string_index(np, "ti,lmp92001-adc-mode", 0,
> + &conversion);
> + if (!ret) {
> + if (strncmp("continuous", conversion, 10) == 0) {
> + cgen |= 1;
> + } else if (strncmp("single-shot", conversion, 11) == 0) {
> + /* Okay */
> + } else {
> + dev_warn(&pdev->dev,
> + "wrong adc mode! set to single-short conversion\n");
> + }
> + } else
> + dev_info(&pdev->dev,
> + "single-short conversion was chosen by default\n");
> +
> + /* Lock the HW registers and set conversion mode. */
> + ret = regmap_update_bits(lmp92001->regmap,
> + LMP92001_CGEN, CGEN_LCK | CGEN_STRT,
> + cgen | CGEN_LCK);
> + if (ret < 0)
> + return ret;
> +
> + platform_set_drvdata(pdev, indio_dev);
> +
> + return devm_iio_device_register(&pdev->dev, indio_dev);
> +}
> +
> +static int lmp92001_adc_remove(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> +
> + /*
> + * To stop ADC conversion to save power
> + *
> + * Unlock the HW registers.
> + * Set conversion mode to single-shot.
> + * Lock the HW registers.
> + */
> + regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, 0);
> + regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_STRT, 0);
> + regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, CGEN_LCK);
> +
> + devm_iio_device_unregister(&pdev->dev, indio_dev);

the unregister is called automatically since devm_


> +
> + return 0;
> +}
> +
> +static struct platform_driver lmp92001_adc_driver = {
> + .driver.name = "lmp92001-adc",
> + .probe = lmp92001_adc_probe,
> + .remove = lmp92001_adc_remove,
> +};
> +
> +static int __init lmp92001_adc_init(void)
> +{
> + return platform_driver_register(&lmp92001_adc_driver);
> +}
> +subsys_initcall(lmp92001_adc_init);
> +
> +static void __exit lmp92001_adc_exit(void)
> +{
> + platform_driver_unregister(&lmp92001_adc_driver);
> +}
> +module_exit(lmp92001_adc_exit);
> +
> +MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@xxxxxxxxx>");
> +MODULE_DESCRIPTION("IIO ADC interface for TI LMP92001");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:lmp92001-adc");
> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
> index 25bed2d..3e0d816 100644
> --- a/drivers/iio/dac/Kconfig
> +++ b/drivers/iio/dac/Kconfig
> @@ -221,6 +221,15 @@ config DPOT_DAC
> To compile this driver as a module, choose M here: the module will be
> called dpot-dac.
>
> +config LMP92001_DAC
> + tristate "TI LMP92001 DAC Driver"
> + depends on MFD_LMP92001
> + help
> + If you say yes here you get support for TI LMP92001 DACs.
> +
> + This driver can also be built as a module. If so, the module will
> + be called lmp92001_dac.
> +
> config LPC18XX_DAC
> tristate "NXP LPC18xx DAC driver"
> depends on ARCH_LPC18XX || COMPILE_TEST
> diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
> index 603587c..516d2be 100644
> --- a/drivers/iio/dac/Makefile
> +++ b/drivers/iio/dac/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_AD7303) += ad7303.o
> obj-$(CONFIG_AD8801) += ad8801.o
> obj-$(CONFIG_CIO_DAC) += cio-dac.o
> obj-$(CONFIG_DPOT_DAC) += dpot-dac.o
> +obj-$(CONFIG_LMP92001_DAC) += lmp92001-dac.o
> obj-$(CONFIG_LPC18XX_DAC) += lpc18xx_dac.o
> obj-$(CONFIG_LTC2632) += ltc2632.o
> obj-$(CONFIG_M62332) += m62332.o
> diff --git a/drivers/iio/dac/lmp92001-dac.c b/drivers/iio/dac/lmp92001-dac.c
> new file mode 100644
> index 0000000..8ea981b
> --- /dev/null
> +++ b/drivers/iio/dac/lmp92001-dac.c
> @@ -0,0 +1,390 @@
> +/*
> + * lmp92001-dac.c - Support for TI LMP92001 DACs
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/iio/iio.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/mfd/lmp92001/core.h>
> +
> +#define CREF_DEXT (1 << 0) /* 1 - DAC external reference.

use prefix
BIT()

> + * 0 - DAC internal reference.
> + */
> +#define CDAC_OFF (1 << 0) /* 1 - Forces all outputs to high impedance. */
> +#define CDAC_OLVL (1 << 1) /* 1 - Cy=0 will force associated OUTx outputs
> + * to VDD.
> + * 0 - Cy=0 will force associated OUTx outputs
> + * to GND.
> + */
> +#define CDAC_GANG (1 << 2) /* Controls the association of analog output

I think I've seen this before... can avoid duplication?

> + * channels OUTx with asynchronous control
> + * inputs Cy.
> + *
> + * Cy to OUTx Assignment
> + * --------------------------------------
> + * | Cy | CDAC:GANG = 0 | CDAC:GANG = 1 |
> + * --------------------------------------
> + * | C1 | OUT[1:4] | OUT[1:3] |
> + * --------------------------------------
> + * | C2 | OUT[5:6] | OUT[4:6] |
> + * --------------------------------------
> + * | C3 | OUT[7:8] | OUT[7:9] |
> + * --------------------------------------
> + * | C4 | OUT[9:12] | OUT[10:12] |
> + * --------------------------------------
> + */
> +
> +static int lmp92001_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *channel,
> + int *val, int *val2,
> + long mask)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + int ret;
> +
> + mutex_lock(&lmp92001->dac_lock);

please restructure code there, this can be a lot simpler and with less
lines

> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + switch (channel->type) {
> + case IIO_VOLTAGE:
> + ret = regmap_read(lmp92001->regmap,
> + 0x7F + channel->channel, val);
> + if (ret < 0)
> + goto exit;
> +
> + ret = IIO_VAL_INT;
> + goto exit;
> + break;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + /* In case of no match channel info/type is return here. */
> + ret = -EINVAL;
> +
> +exit:
> + mutex_unlock(&lmp92001->dac_lock);
> +
> + return ret;
> +}
> +
> +int lmp92001_write_raw(struct iio_dev *indio_dev,

static

> + struct iio_chan_spec const *channel,
> + int val, int val2,
> + long mask)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + int ret;
> +
> + mutex_lock(&lmp92001->dac_lock);

restructure code; lock only needed only around _write() if at all

> +
> + if (val < 0 || val > 4095) {
> + ret = -EINVAL;
> + goto exit;
> + }
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + switch (channel->type) {
> + case IIO_VOLTAGE:
> + ret = regmap_write(lmp92001->regmap,
> + 0x7F + channel->channel, val);
> + if (ret < 0)
> + goto exit;
> +
> + ret = 0;
> + goto exit;
> + break;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + /* In case of no match channel info/type is return here. */
> + ret = -EINVAL;
> +
> +exit:
> + mutex_unlock(&lmp92001->dac_lock);
> +
> + return ret;
> +}
> +
> +static const struct iio_info lmp92001_info = {
> + .read_raw = lmp92001_read_raw,
> + .write_raw = lmp92001_write_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +ssize_t lmp92001_dvref_read(struct iio_dev *indio_dev, uintptr_t private,

static

> + struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cref;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CREF, &cref);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%s\n", cref & CREF_DEXT ? "external" : "internal");
> +}
> +
> +ssize_t lmp92001_dvref_write(struct iio_dev *indio_dev, uintptr_t private,
> + struct iio_chan_spec const *channel, const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cref;
> + int ret;
> +
> + if (strncmp("external", buf, 8) == 0)

strcmp()

> + cref = 1;
> + else if (strncmp("internal", buf, 8) == 0)
> + cref = 0;
> + else
> + return -EINVAL;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CREF, CREF_DEXT,
> + cref);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +ssize_t lmp92001_outx_read(struct iio_dev *indio_dev, uintptr_t private,

static

> + struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cdac;
> + const char *outx;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CDAC, &cdac);
> + if (ret < 0)
> + return ret;
> +
> + if (cdac & CDAC_OFF)
> + outx = "hiz";
> + else {
> + if (cdac & CDAC_OLVL)
> + outx = "1 or dac";
> + else
> + outx = "0 or dac";
> + }
> +
> + return sprintf(buf, "%s\n", outx);
> +}
> +
> +ssize_t lmp92001_outx_write(struct iio_dev *indio_dev, uintptr_t private,

static

> + struct iio_chan_spec const *channel, const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cdac, mask;
> + int ret;
> +
> + if (strncmp("hiz", buf, 3) == 0) {
> + cdac = CDAC_OFF;
> + mask = CDAC_OFF;
> + } else if (strncmp("dac", buf, 3) == 0) {
> + cdac = ~CDAC_OFF;
> + mask = CDAC_OFF;
> + } else if (strncmp("0", buf, 1) == 0) {
> + cdac = ~(CDAC_OLVL | CDAC_OFF);
> + mask = CDAC_OLVL | CDAC_OFF;
> + } else if (strncmp("1", buf, 1) == 0) {
> + cdac = CDAC_OLVL;
> + mask = CDAC_OLVL | CDAC_OFF;
> + } else
> + return -EINVAL;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CDAC, mask, cdac);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +ssize_t lmp92001_gang_read(struct iio_dev *indio_dev, uintptr_t private,
> + struct iio_chan_spec const *channel, char *buf)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cdac;
> + int ret;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_CDAC, &cdac);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%s\n", cdac & CDAC_GANG ? "1" : "0");
> +}
> +
> +ssize_t lmp92001_gang_write(struct iio_dev *indio_dev, uintptr_t private,

static

> + struct iio_chan_spec const *channel, const char *buf, size_t len)
> +{
> + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
> + unsigned int cdac = 0;
> + int ret;
> +
> + if (strncmp("0", buf, 1) == 0)
> + cdac = ~CDAC_GANG;
> + else if (strncmp("1", buf, 1) == 0)
> + cdac = CDAC_GANG;
> + else
> + return -EINVAL;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CDAC, CDAC_GANG,
> + cdac);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +static const struct iio_chan_spec_ext_info lmp92001_ext_info[] = {
> + {
> + .name = "vref",
> + .read = lmp92001_dvref_read,
> + .write = lmp92001_dvref_write,
> + .shared = IIO_SHARED_BY_ALL,
> + },
> + {
> + .name = "outx",
> + .read = lmp92001_outx_read,
> + .write = lmp92001_outx_write,
> + .shared = IIO_SHARED_BY_ALL,
> + },
> + {
> + .name = "gang",
> + .read = lmp92001_gang_read,
> + .write = lmp92001_gang_write,
> + .shared = IIO_SHARED_BY_ALL,
> + },
> + { },
> +};
> +
> +#define LMP92001_CHAN_SPEC(_ch) \
> +{ \
> + .channel = _ch, \
> + .type = IIO_VOLTAGE, \
> + .indexed = 1, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .ext_info = lmp92001_ext_info, \
> + .output = 1, \
> +}
> +
> +static const struct iio_chan_spec lmp92001_dac_channels[] = {
> + LMP92001_CHAN_SPEC(1),
> + LMP92001_CHAN_SPEC(2),
> + LMP92001_CHAN_SPEC(3),
> + LMP92001_CHAN_SPEC(4),
> + LMP92001_CHAN_SPEC(5),
> + LMP92001_CHAN_SPEC(6),
> + LMP92001_CHAN_SPEC(7),
> + LMP92001_CHAN_SPEC(8),
> + LMP92001_CHAN_SPEC(9),
> + LMP92001_CHAN_SPEC(10),
> + LMP92001_CHAN_SPEC(11),
> + LMP92001_CHAN_SPEC(12),
> +};
> +
> +static int lmp92001_dac_probe(struct platform_device *pdev)
> +{
> + struct lmp92001 *lmp92001 = dev_get_drvdata(pdev->dev.parent);
> + struct iio_dev *indio_dev;
> + struct device_node *np = pdev->dev.of_node;
> + u8 gang = 0, outx = 0, hiz = 0;
> + unsigned int cdac = 0;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*lmp92001));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + mutex_init(&lmp92001->dac_lock);
> +
> + iio_device_set_drvdata(indio_dev, lmp92001);
> +
> + indio_dev->name = pdev->name;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->info = &lmp92001_info;
> + indio_dev->channels = lmp92001_dac_channels;
> + indio_dev->num_channels = ARRAY_SIZE(lmp92001_dac_channels);
> +
> + of_property_read_u8(np, "ti,lmp92001-dac-hiz", &hiz);
> + cdac |= hiz;
> +
> + of_property_read_u8(np, "ti,lmp92001-dac-outx", &outx);
> + cdac |= outx << 1;
> +
> + of_property_read_u8(np, "ti,lmp92001-dac-gang", &gang);
> + cdac |= gang << 2;
> +
> + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CDAC,
> + CDAC_GANG | CDAC_OLVL | CDAC_OFF, cdac);
> + if (ret < 0)
> + return ret;
> +
> + platform_set_drvdata(pdev, indio_dev);
> +
> + return devm_iio_device_register(&pdev->dev, indio_dev);
> +}
> +
> +static int lmp92001_dac_remove(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> +
> + devm_iio_device_unregister(&pdev->dev, indio_dev);

devm_.._unregister() not needed

> +
> + return 0;
> +}
> +
> +static struct platform_driver lmp92001_dac_driver = {
> + .driver.name = "lmp92001-dac",
> + .probe = lmp92001_dac_probe,
> + .remove = lmp92001_dac_remove,
> +};
> +
> +static int __init lmp92001_dac_init(void)
> +{
> + return platform_driver_register(&lmp92001_dac_driver);
> +}
> +subsys_initcall(lmp92001_dac_init);
> +
> +static void __exit lmp92001_dac_exit(void)
> +{
> + platform_driver_unregister(&lmp92001_dac_driver);
> +}
> +module_exit(lmp92001_dac_exit);
> +
> +MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@xxxxxxxxx>");
> +MODULE_DESCRIPTION("IIO DAC interface for TI LMP92001");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:lmp92001-dac");
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 94ad2c1..a20389a 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1528,6 +1528,18 @@ config MFD_LM3533
> additional drivers must be enabled in order to use the LED,
> backlight or ambient-light-sensor functionality of the device.
>
> +config MFD_LMP92001
> + tristate "TI LMP92001 Analog System Monitor and Controller"
> + depends on I2C
> + select MFD_CORE
> + select REGMAP_I2C
> + help
> + Say yes here to enable support for TI LMP92001 Analog System
> + Monitor and Controller
> +
> + This driver provide support for 16 ADC, 12 DAC, Voltage Reference,
> + Analog Temperature Sensor and 8-bit GPIO Port.
> +
> config MFD_TIMBERDALE
> tristate "Timberdale FPGA"
> select MFD_CORE
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 080793b..20d2e65 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -199,6 +199,10 @@ obj-$(CONFIG_MFD_RN5T618) += rn5t618.o
> obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o
> obj-$(CONFIG_MFD_SYSCON) += syscon.o
> obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o
> +
> +lmp92001-objs := lmp92001-core.o lmp92001-i2c.o lmp92001-debug.o
> +obj-$(CONFIG_MFD_LMP92001) += lmp92001.o
> +
> obj-$(CONFIG_MFD_VEXPRESS_SYSREG) += vexpress-sysreg.o
> obj-$(CONFIG_MFD_RETU) += retu-mfd.o
> obj-$(CONFIG_MFD_AS3711) += as3711.o
> diff --git a/drivers/mfd/lmp92001-core.c b/drivers/mfd/lmp92001-core.c
> new file mode 100644
> index 0000000..55bc9ab
> --- /dev/null
> +++ b/drivers/mfd/lmp92001-core.c
> @@ -0,0 +1,308 @@
> +/*
> + * lmp92001-core.c - Device access for TI LMP92001
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/mfd/lmp92001/core.h>
> +#include <linux/mfd/lmp92001/debug.h>
> +
> +static const struct mfd_cell lmp92001_devs[] = {
> + {
> + .name = "lmp92001-gpio",
> + .of_compatible = "ti,lmp92001-gpio",
> + },
> + {
> + .name = "lmp92001-adc",
> + .of_compatible = "ti,lmp92001-adc",
> + },
> + {
> + .name = "lmp92001-dac",
> + .of_compatible = "ti,lmp92001-dac",
> + },
> +};
> +
> +static struct reg_default lmp92001_defaults[] = {
> + { LMP92001_SGEN, 0x40 },
> + { LMP92001_SHIL, 0x00 },
> + { LMP92001_SLOL, 0x00 },
> + { LMP92001_CGEN, 0x00 },
> + { LMP92001_CDAC, 0x03 },
> + { LMP92001_CGPO, 0xFF },
> + { LMP92001_CINH, 0x00 },
> + { LMP92001_CINL, 0x00 },
> + { LMP92001_CAD1, 0x00 },
> + { LMP92001_CAD2, 0x00 },
> + { LMP92001_CAD3, 0x00 },
> + { LMP92001_CTRIG, 0x00 },
> + { LMP92001_CREF, 0x07 },
> + { LMP92001_ADC1, 0x0000 },
> + { LMP92001_ADC2, 0x0000 },
> + { LMP92001_ADC3, 0x0000 },
> + { LMP92001_ADC4, 0x0000 },
> + { LMP92001_ADC5, 0x0000 },
> + { LMP92001_ADC6, 0x0000 },
> + { LMP92001_ADC7, 0x0000 },
> + { LMP92001_ADC8, 0x0000 },
> + { LMP92001_ADC9, 0x0000 },
> + { LMP92001_ADC10, 0x0000 },
> + { LMP92001_ADC11, 0x0000 },
> + { LMP92001_ADC12, 0x0000 },
> + { LMP92001_ADC13, 0x0000 },
> + { LMP92001_ADC14, 0x0000 },
> + { LMP92001_ADC15, 0x0000 },
> + { LMP92001_ADC16, 0x0000 },
> + { LMP92001_LIH1, 0x0FFF },
> + { LMP92001_LIH2, 0x0FFF },
> + { LMP92001_LIH3, 0x0FFF },
> + { LMP92001_LIH9, 0x0FFF },
> + { LMP92001_LIH10, 0x0FFF },
> + { LMP92001_LIH11, 0x0FFF },
> + { LMP92001_LIL1, 0x0000 },
> + { LMP92001_LIL2, 0x0000 },
> + { LMP92001_LIL3, 0x0000 },
> + { LMP92001_LIL9, 0x0000 },
> + { LMP92001_LIL10, 0x0000 },
> + { LMP92001_LIL11, 0x0000 },
> + { LMP92001_DAC1, 0x0000 },
> + { LMP92001_DAC2, 0x0000 },
> + { LMP92001_DAC3, 0x0000 },
> + { LMP92001_DAC4, 0x0000 },
> + { LMP92001_DAC5, 0x0000 },
> + { LMP92001_DAC6, 0x0000 },
> + { LMP92001_DAC7, 0x0000 },
> + { LMP92001_DAC8, 0x0000 },
> + { LMP92001_DAC9, 0x0000 },
> + { LMP92001_DAC10, 0x0000 },
> + { LMP92001_DAC11, 0x0000 },
> + { LMP92001_DAC12, 0x0000 },
> + { LMP92001_DALL, 0x0000 },
> +};
> +
> +static bool lmp92001_reg_readable(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case LMP92001_ID:
> + case LMP92001_VER:
> + case LMP92001_SGEN:
> + case LMP92001_SGPI:
> + case LMP92001_SHIL:
> + case LMP92001_SLOL:
> + case LMP92001_CGEN:
> + case LMP92001_CDAC:
> + case LMP92001_CGPO:
> + case LMP92001_CINH:
> + case LMP92001_CINL:
> + case LMP92001_CAD1:
> + case LMP92001_CAD2:
> + case LMP92001_CAD3:
> + case LMP92001_ADC1:
> + case LMP92001_ADC2:
> + case LMP92001_ADC3:
> + case LMP92001_ADC4:
> + case LMP92001_ADC5:
> + case LMP92001_ADC6:
> + case LMP92001_ADC7:
> + case LMP92001_ADC8:
> + case LMP92001_ADC9:
> + case LMP92001_ADC10:
> + case LMP92001_ADC11:
> + case LMP92001_ADC12:
> + case LMP92001_ADC13:
> + case LMP92001_ADC14:
> + case LMP92001_ADC15:
> + case LMP92001_ADC16:
> + case LMP92001_ADC17:
> + case LMP92001_LIH1:
> + case LMP92001_LIH2:
> + case LMP92001_LIH3:
> + case LMP92001_LIH9:
> + case LMP92001_LIH10:
> + case LMP92001_LIH11:
> + case LMP92001_LIL1:
> + case LMP92001_LIL2:
> + case LMP92001_LIL3:
> + case LMP92001_LIL9:
> + case LMP92001_LIL10:
> + case LMP92001_LIL11:
> + case LMP92001_CREF:
> + case LMP92001_DAC1:
> + case LMP92001_DAC2:
> + case LMP92001_DAC3:
> + case LMP92001_DAC4:
> + case LMP92001_DAC5:
> + case LMP92001_DAC6:
> + case LMP92001_DAC7:
> + case LMP92001_DAC8:
> + case LMP92001_DAC9:
> + case LMP92001_DAC10:
> + case LMP92001_DAC11:
> + case LMP92001_DAC12:
> + case LMP92001_BLK0:
> + case LMP92001_BLK1:
> + case LMP92001_BLK2:
> + case LMP92001_BLK3:
> + case LMP92001_BLK4:
> + case LMP92001_BLK5:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static bool lmp92001_reg_writeable(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case LMP92001_CGEN:
> + case LMP92001_CDAC:
> + case LMP92001_CGPO:
> + case LMP92001_CINH:
> + case LMP92001_CINL:
> + case LMP92001_CAD1:
> + case LMP92001_CAD2:
> + case LMP92001_CAD3:
> + case LMP92001_CTRIG:
> + case LMP92001_LIH1:
> + case LMP92001_LIH2:
> + case LMP92001_LIH3:
> + case LMP92001_LIH9:
> + case LMP92001_LIH10:
> + case LMP92001_LIH11:
> + case LMP92001_LIL1:
> + case LMP92001_LIL2:
> + case LMP92001_LIL3:
> + case LMP92001_LIL9:
> + case LMP92001_LIL10:
> + case LMP92001_LIL11:
> + case LMP92001_CREF:
> + case LMP92001_DAC1:
> + case LMP92001_DAC2:
> + case LMP92001_DAC3:
> + case LMP92001_DAC4:
> + case LMP92001_DAC5:
> + case LMP92001_DAC6:
> + case LMP92001_DAC7:
> + case LMP92001_DAC8:
> + case LMP92001_DAC9:
> + case LMP92001_DAC10:
> + case LMP92001_DAC11:
> + case LMP92001_DAC12:
> + case LMP92001_DALL:
> + case LMP92001_BLK0:
> + case LMP92001_BLK1:
> + case LMP92001_BLK4:
> + case LMP92001_BLK5:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static bool lmp92001_reg_volatile(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case LMP92001_SGEN:
> + case LMP92001_SGPI:
> + case LMP92001_SHIL:
> + case LMP92001_SLOL:
> + case LMP92001_CGEN:
> + case LMP92001_ADC1:
> + case LMP92001_ADC2:
> + case LMP92001_ADC3:
> + case LMP92001_ADC4:
> + case LMP92001_ADC5:
> + case LMP92001_ADC6:
> + case LMP92001_ADC7:
> + case LMP92001_ADC8:
> + case LMP92001_ADC9:
> + case LMP92001_ADC10:
> + case LMP92001_ADC11:
> + case LMP92001_ADC12:
> + case LMP92001_ADC13:
> + case LMP92001_ADC14:
> + case LMP92001_ADC15:
> + case LMP92001_ADC16:
> + case LMP92001_ADC17:
> + case LMP92001_BLK2:
> + case LMP92001_BLK3:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +struct regmap_config lmp92001_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 16,
> +
> + .cache_type = REGCACHE_RBTREE,
> +
> + .reg_defaults = lmp92001_defaults,
> + .num_reg_defaults = ARRAY_SIZE(lmp92001_defaults),
> +
> + .max_register = LMP92001_BLK5,
> + .readable_reg = lmp92001_reg_readable,
> + .writeable_reg = lmp92001_reg_writeable,
> + .volatile_reg = lmp92001_reg_volatile,
> +};
> +
> +int lmp92001_device_init(struct lmp92001 *lmp92001, unsigned long id, int irq)
> +{
> + int ret;
> + unsigned int comid, ver;
> +
> + dev_set_drvdata(lmp92001->dev, lmp92001);
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_ID, &comid);
> + if (ret < 0) {
> + dev_err(lmp92001->dev, "failed to read Company ID: %d\n", ret);
> + goto exit;
> + }
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_VER, &ver);
> + if (ret < 0) {
> + dev_err(lmp92001->dev, "failed to read Version: %d\n", ret);
> + goto exit;
> + }
> +
> + dev_info(lmp92001->dev, "Company ID 0x%.2x, Version 0x%.2x\n",
> + comid, ver);
> +
> + ret = mfd_add_devices(lmp92001->dev, PLATFORM_DEVID_AUTO,
> + lmp92001_devs, ARRAY_SIZE(lmp92001_devs),
> + NULL, 0, NULL);
> + if (ret != 0) {
> + dev_err(lmp92001->dev, "failed to add children\n");
> + goto exit;
> + }
> +
> + ret = lmp92001_debug_init(lmp92001);
> + if (ret < 0) {
> + dev_err(lmp92001->dev, "failed to initial debug fs.\n");
> + goto exit;
> + }
> +
> +exit:
> + return ret;
> +}
> +
> +void lmp92001_device_exit(struct lmp92001 *lmp92001)
> +{
> + lmp92001_debug_exit(lmp92001);
> + mfd_remove_devices(lmp92001->dev);
> +}
> diff --git a/drivers/mfd/lmp92001-debug.c b/drivers/mfd/lmp92001-debug.c
> new file mode 100644
> index 0000000..d733e67
> --- /dev/null
> +++ b/drivers/mfd/lmp92001-debug.c
> @@ -0,0 +1,67 @@
> +/*
> + * lmp92001-debug.c - Debug file system for TI LMP92001
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +
> +#include <linux/mfd/lmp92001/core.h>
> +
> +static ssize_t lmp92001_id_ver_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct lmp92001 *lmp92001 = dev_get_drvdata(dev);
> + int ret;
> + unsigned int comid, ver;
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_ID, &comid);
> + if (ret < 0) {
> + dev_err(lmp92001->dev, "failed to read Company ID: %d\n", ret);
> + return 0;
> + }
> +
> + ret = regmap_read(lmp92001->regmap, LMP92001_VER, &ver);
> + if (ret < 0) {
> + dev_err(lmp92001->dev, "failed to read Version: %d\n", ret);
> + return 0;
> + }
> +
> + ret = sprintf(buf, "Company ID 0x%02x (%d), Version 0x%02x (%d)\n",
> + comid, comid, ver, ver);
> +
> + return ret;
> +}
> +static DEVICE_ATTR(lmp92001_id_ver, 0444, lmp92001_id_ver_show, NULL);
> +
> +int lmp92001_debug_init(struct lmp92001 *lmp92001)
> +{
> + int ret;
> +
> + ret = device_create_file(lmp92001->dev, &dev_attr_lmp92001_id_ver);
> + if (ret != 0)
> + dev_err(lmp92001->dev,
> + "unique ID attribute is not created: %d\n", ret);
> +
> + return ret;
> +}
> +
> +void lmp92001_debug_exit(struct lmp92001 *lmp92001)
> +{
> + device_remove_file(lmp92001->dev, &dev_attr_lmp92001_id_ver);
> +}
> diff --git a/drivers/mfd/lmp92001-i2c.c b/drivers/mfd/lmp92001-i2c.c
> new file mode 100644
> index 0000000..bbb1dad
> --- /dev/null
> +++ b/drivers/mfd/lmp92001-i2c.c
> @@ -0,0 +1,215 @@
> +/*
> + * lmp92001-i2c.c - I2C access for TI LMP92001
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include <linux/mfd/lmp92001/core.h>
> +
> +static const unsigned short lmp92001_i2c_addresses[] = {
> + 0x40, 0x42, 0x44, 0x46, 0x48, 0x4A, 0x4C, 0x4E, 0x50, I2C_CLIENT_END
> +};
> +
> +/* TODO: To read/write block access, it may need to re-ordering endianness! */
> +static int lmp92001_reg_read(void *context, unsigned int reg, unsigned int *val)
> +{
> + struct device *dev = context;
> + struct i2c_client *i2c = to_i2c_client(dev);
> + int ret;
> +
> + if (reg > 0xff)
> + return -EINVAL;
> +
> + switch (reg) {
> + case LMP92001_ID ... LMP92001_CTRIG:
> + case LMP92001_CREF:
> + ret = i2c_smbus_read_byte_data(i2c, reg);
> + break;
> + case LMP92001_ADC1 ... LMP92001_LIL11:
> + case LMP92001_DAC1 ... LMP92001_DALL:
> + ret = i2c_smbus_read_word_swapped(i2c, reg);
> + break;
> + case LMP92001_BLK0 ... LMP92001_BLK5:
> + ret = i2c_smbus_read_block_data(i2c, reg,
> + (u8 *)((uintptr_t)*val));
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (ret < 0)
> + return ret;
> +
> + if (reg <= LMP92001_DALL)
> + *val = ret;
> +
> + return 0;
> +}
> +
> +static int lmp92001_reg_write(void *context, unsigned int reg, unsigned int val)
> +{
> + struct device *dev = context;
> + struct i2c_client *i2c = to_i2c_client(dev);
> + int ret;
> +
> + if (reg > 0xff)
> + return -EINVAL;
> +
> + switch (reg) {
> + case LMP92001_ID ... LMP92001_CTRIG:
> + case LMP92001_CREF:
> + ret = i2c_smbus_write_byte_data(i2c, reg, val);
> + break;
> + case LMP92001_ADC1 ... LMP92001_LIL11:
> + case LMP92001_DAC1 ... LMP92001_DALL:
> + ret = i2c_smbus_write_word_swapped(i2c, reg, val);
> + break;
> + /* To call this function/case, must be passed val as pointer */
> + case LMP92001_BLK0:
> + case LMP92001_BLK4:
> + ret = i2c_smbus_write_block_data(i2c, reg, 24,
> + (u8 *)((uintptr_t)val));
> + break;
> + case LMP92001_BLK1:
> + case LMP92001_BLK5:
> + ret = i2c_smbus_write_block_data(i2c, reg, 12,
> + (u8 *)((uintptr_t)val));
> + break;
> + case LMP92001_BLK2:
> + ret = i2c_smbus_write_block_data(i2c, reg, 34,
> + (u8 *)((uintptr_t)val));
> + break;
> + case LMP92001_BLK3:
> + ret = i2c_smbus_write_block_data(i2c, reg, 18,
> + (u8 *)((uintptr_t)val));
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> +static int lmp92001_i2c_probe(struct i2c_client *i2c,
> + const struct i2c_device_id *id)
> +{
> + struct lmp92001 *lmp92001;
> + int ret;
> +
> + lmp92001 = devm_kzalloc(&i2c->dev, sizeof(struct lmp92001), GFP_KERNEL);
> + if (!lmp92001)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(i2c, lmp92001);
> + lmp92001->dev = &i2c->dev;
> +
> + lmp92001_regmap_config.reg_read = lmp92001_reg_read;
> + lmp92001_regmap_config.reg_write = lmp92001_reg_write;
> +
> + lmp92001->regmap = devm_regmap_init(&i2c->dev, NULL, &i2c->dev,
> + &lmp92001_regmap_config);
> + if (IS_ERR(lmp92001->regmap)) {
> + ret = PTR_ERR(lmp92001->regmap);
> + dev_err(lmp92001->dev, "failed to allocate register map: %d\n",
> + ret);
> + return ret;
> + }
> +
> + return lmp92001_device_init(lmp92001, id->driver_data, i2c->irq);
> +}
> +
> +static int lmp92001_i2c_remove(struct i2c_client *i2c)
> +{
> + struct lmp92001 *lmp92001 = i2c_get_clientdata(i2c);
> +
> + lmp92001_device_exit(lmp92001);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_OF
> +static const struct of_device_id lmp92001_dt_ids[] = {
> + { .compatible = "ti,lmp92001", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, lmp92001_dt_ids);
> +#endif
> +
> +static const struct i2c_device_id lmp92001_i2c_ids[] = {
> + { "lmp92001" },
> + { },
> +};
> +MODULE_DEVICE_TABLE(i2c, lmp92001_i2c_ids);
> +
> +static int lmp92001_i2c_detect(struct i2c_client *i2c,
> + struct i2c_board_info *info)
> +{
> + struct i2c_adapter *adapter = i2c->adapter;
> + s32 comid, ver;
> +
> + if (!i2c_check_functionality(adapter,
> + I2C_FUNC_SMBUS_BYTE_DATA |
> + I2C_FUNC_SMBUS_WORD_DATA |
> + I2C_FUNC_SMBUS_BLOCK_DATA))
> + return -ENODEV;
> +
> + comid = i2c_smbus_read_byte_data(i2c, LMP92001_ID);
> + ver = i2c_smbus_read_byte_data(i2c, LMP92001_VER);
> +
> + if (comid != 0x01 || ver != 0x10)
> + return -ENODEV;
> +
> + return 0;
> +}
> +
> +static struct i2c_driver lmp92001_i2c_driver = {
> + .driver = {
> + .name = "lmp92001",
> + .of_match_table = of_match_ptr(lmp92001_dt_ids),
> + },
> + .probe = lmp92001_i2c_probe,
> + .remove = lmp92001_i2c_remove,
> + .id_table = lmp92001_i2c_ids,
> + .detect = lmp92001_i2c_detect,
> + .address_list = lmp92001_i2c_addresses,
> +};
> +
> +static int __init lmp92001_i2c_init(void)
> +{
> + return i2c_add_driver(&lmp92001_i2c_driver);
> +}
> +subsys_initcall(lmp92001_i2c_init);
> +
> +static void __exit lmp92001_i2c_exit(void)
> +{
> + i2c_del_driver(&lmp92001_i2c_driver);
> +}
> +module_exit(lmp92001_i2c_exit);
> +
> +MODULE_DESCRIPTION("i2c driver for TI LMP92001");
> +MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@xxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/lmp92001/core.h b/include/linux/mfd/lmp92001/core.h
> new file mode 100644
> index 0000000..9039000
> --- /dev/null
> +++ b/include/linux/mfd/lmp92001/core.h
> @@ -0,0 +1,119 @@
> +/*
> + * include/linux/mfd/lmp92001/core.h - Core interface for TI LMP92001
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#ifndef __MFD_LMP92001_CORE_H__
> +#define __MFD_LMP92001_CORE_H__
> +
> +#include <linux/device.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mutex.h>
> +#include <linux/regmap.h>
> +
> +/*
> + * Register values.
> + */
> +/* ID */
> +#define LMP92001_ID 0x0E
> +#define LMP92001_VER 0x0F
> +/* STATUS */
> +#define LMP92001_SGEN 0x10
> +#define LMP92001_SGPI 0x11
> +#define LMP92001_SHIL 0x12
> +#define LMP92001_SLOL 0x13
> +/* CONTROL */
> +#define LMP92001_CGEN 0x14
> +#define LMP92001_CDAC 0x15
> +#define LMP92001_CGPO 0x16
> +#define LMP92001_CINH 0x17
> +#define LMP92001_CINL 0x18
> +#define LMP92001_CAD1 0x19
> +#define LMP92001_CAD2 0x1A
> +#define LMP92001_CAD3 0x1B
> +#define LMP92001_CTRIG 0x1C
> +/* ADC OUTPUT DATA */
> +#define LMP92001_ADC1 0x20
> +#define LMP92001_ADC2 0x21
> +#define LMP92001_ADC3 0x22
> +#define LMP92001_ADC4 0x23
> +#define LMP92001_ADC5 0x24
> +#define LMP92001_ADC6 0x25
> +#define LMP92001_ADC7 0x26
> +#define LMP92001_ADC8 0x27
> +#define LMP92001_ADC9 0x28
> +#define LMP92001_ADC10 0x29
> +#define LMP92001_ADC11 0x2A
> +#define LMP92001_ADC12 0x2B
> +#define LMP92001_ADC13 0x2C
> +#define LMP92001_ADC14 0x2D
> +#define LMP92001_ADC15 0x2E
> +#define LMP92001_ADC16 0x2F
> +#define LMP92001_ADC17 0x30
> +/* ADC WINDOW COMPARATOR LIMITS */
> +#define LMP92001_LIH1 0x40
> +#define LMP92001_LIH2 0x41
> +#define LMP92001_LIH3 0x42
> +#define LMP92001_LIH9 0x43
> +#define LMP92001_LIH10 0x44
> +#define LMP92001_LIH11 0x45
> +#define LMP92001_LIL1 0x46
> +#define LMP92001_LIL2 0x47
> +#define LMP92001_LIL3 0x48
> +#define LMP92001_LIL9 0x49
> +#define LMP92001_LIL10 0x4A
> +#define LMP92001_LIL11 0x4B
> +/* INTERNAL REFERENCE CONTROL */
> +#define LMP92001_CREF 0x66
> +/* DAC INPUT DATA */
> +#define LMP92001_DAC1 0x80
> +#define LMP92001_DAC2 0x81
> +#define LMP92001_DAC3 0x82
> +#define LMP92001_DAC4 0x83
> +#define LMP92001_DAC5 0x84
> +#define LMP92001_DAC6 0x85
> +#define LMP92001_DAC7 0x86
> +#define LMP92001_DAC8 0x87
> +#define LMP92001_DAC9 0x88
> +#define LMP92001_DAC10 0x89
> +#define LMP92001_DAC11 0x8A
> +#define LMP92001_DAC12 0x8B
> +#define LMP92001_DALL 0x90
> +/* MEMORY MAPPED BLOCK COMMANDS */
> +#define LMP92001_BLK0 0xF0
> +#define LMP92001_BLK1 0xF1
> +#define LMP92001_BLK2 0xF2
> +#define LMP92001_BLK3 0xF3
> +#define LMP92001_BLK4 0xF4
> +#define LMP92001_BLK5 0xF5
> +
> +struct lmp92001 {
> + struct device *dev;
> + struct regmap *regmap;
> +
> + struct mutex adc_lock;
> + struct mutex dac_lock;
> +};
> +
> +extern struct regmap_config lmp92001_regmap_config;
> +
> +int lmp92001_device_init(struct lmp92001 *lmp92001, unsigned long id, int irq);
> +void lmp92001_device_exit(struct lmp92001 *lmp92001);
> +
> +#endif /* __MFD_LMP92001_CORE_H__ */
> diff --git a/include/linux/mfd/lmp92001/debug.h b/include/linux/mfd/lmp92001/debug.h
> new file mode 100644
> index 0000000..efef95f
> --- /dev/null
> +++ b/include/linux/mfd/lmp92001/debug.h
> @@ -0,0 +1,28 @@
> +/*
> + * include/linux/mfd/lmp92001/debug.h - Debug interface for TI 92001
> + *
> + * Copyright 2016-2017 Celestica Ltd.
> + *
> + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> + *
> + * Inspired by wm831x 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.
> + *
> + * 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.
> + *
> + */
> +
> +#ifndef __MFD_LMP92001_DEBUG_H__
> +#define __MFD_LMP92001_DEBUG_H__
> +
> +int lmp92001_debug_init(struct lmp92001 *lmp92001);
> +void lmp92001_debug_exit(struct lmp92001 *lmp92001);
> +
> +#endif /* __MFD_LMP92001_DEBUG_H__ */
>

--

Peter Meerwald-Stadler
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