RE: [PATCH v4 3/3] pinctrl: da9062: add driver support

[Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>]

On 08 January 2020 10:48, Marco Felsch wrote:

> The DA9062 is a mfd pmic device which supports 5 GPIOs. The GPIOs can
> be used as input, output or have a special use-case.
> 
> The patch adds the support for the normal input/output use-case.
> 
> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>

A little late, but:

Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>

> ---
> Changelog:
> v4:
> - add missing PIN_CONFIG_BIAS_DISABLE
> 
> v3:
> - add comment for gpio private include
> - add missing bits.h include
> - add pin_config state container and set initial pin state to push-pull
> - make use of GPIO_LINE_DIRECTION_{IN,OUT}
> - update MAINTAINERS entry -> gpio-da90??.c already covered but not
>   pinctrl-da90??.c
> 
> v2:
> - fix minor style issue
> - move from drivers/gpio to drivers/pinctrl
> - Fix spelling issue
> - rename local gpio_dir to gpio_mode
> - Add datasheet reference and TODO notes
> - move gpio to mfd-root node to avoid hierarchical interrupt chips
> - Add gpio-controller property check
> - remove of_device_id since we drop the gpio of-subnode
> - Drop da9062_gpio_get_hwgpio
> ---
>  MAINTAINERS                      |   1 +
>  drivers/pinctrl/Kconfig          |  12 ++
>  drivers/pinctrl/Makefile         |   1 +
>  drivers/pinctrl/pinctrl-da9062.c | 300 +++++++++++++++++++++++++++++++
>  4 files changed, 314 insertions(+)
>  create mode 100644 drivers/pinctrl/pinctrl-da9062.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index bd5847e802de..9692ff05cd14 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4867,6 +4867,7 @@ F:	drivers/leds/leds-da90??.c
>  F:	drivers/mfd/da903x.c
>  F:	drivers/mfd/da90??-*.c
>  F:	drivers/mfd/da91??-*.c
> +F:	drivers/pinctrl/pinctrl-da90??.c
>  F:	drivers/power/supply/da9052-battery.c
>  F:	drivers/power/supply/da91??-*.c
>  F:	drivers/regulator/da903x.c
> diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
> index 3bfbf2ff6e2b..88a3864f32a5 100644
> --- a/drivers/pinctrl/Kconfig
> +++ b/drivers/pinctrl/Kconfig
> @@ -126,6 +126,18 @@ config PINCTRL_DA850_PUPD
>  	  Driver for TI DA850/OMAP-L138/AM18XX pinconf. Used to control
>  	  pullup/pulldown pin groups.
> 
> +config PINCTRL_DA9062
> +	tristate "Dialog Semiconductor DA9062 PMIC pinctrl and GPIO Support"
> +	depends on MFD_DA9062
> +	select GPIOLIB
> +	help
> +	  The Dialog DA9062 PMIC provides multiple GPIOs that can be muxed for
> +	  different functions. This driver bundles a pinctrl driver to select the
> +	  function muxing and a GPIO driver to handle the GPIO when the GPIO
> +	  function is selected.
> +
> +	  Say yes to enable pinctrl and GPIO support for the DA9062 PMIC.
> +
>  config PINCTRL_DIGICOLOR
>  	bool
>  	depends on OF && (ARCH_DIGICOLOR || COMPILE_TEST)
> diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
> index 879f312bfb75..0b36a1cfca8a 100644
> --- a/drivers/pinctrl/Makefile
> +++ b/drivers/pinctrl/Makefile
> @@ -16,6 +16,7 @@ obj-$(CONFIG_PINCTRL_AT91PIO4)	+= pinctrl-at91-
> pio4.o
>  obj-$(CONFIG_PINCTRL_AMD)	+= pinctrl-amd.o
>  obj-$(CONFIG_PINCTRL_BM1880)	+= pinctrl-bm1880.o
>  obj-$(CONFIG_PINCTRL_DA850_PUPD) += pinctrl-da850-pupd.o
> +obj-$(CONFIG_PINCTRL_DA9062)	+= pinctrl-da9062.o
>  obj-$(CONFIG_PINCTRL_DIGICOLOR)	+= pinctrl-digicolor.o
>  obj-$(CONFIG_PINCTRL_FALCON)	+= pinctrl-falcon.o
>  obj-$(CONFIG_PINCTRL_GEMINI)	+= pinctrl-gemini.o
> diff --git a/drivers/pinctrl/pinctrl-da9062.c b/drivers/pinctrl/pinctrl-da9062.c
> new file mode 100644
> index 000000000000..f704ee0b2fd9
> --- /dev/null
> +++ b/drivers/pinctrl/pinctrl-da9062.c
> @@ -0,0 +1,300 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Dialog DA9062 pinctrl and GPIO driver.
> + * Based on DA9055 GPIO driver.
> + *
> + * TODO:
> + *   - add pinmux and pinctrl support (gpio alternate mode)
> + *
> + * Documents:
> + * [1] https://www.dialog-
> semiconductor.com/sites/default/files/da9062_datasheet_3v6.pdf
> + *
> + * Copyright (C) 2019 Pengutronix, Marco Felsch <kernel@xxxxxxxxxxxxxx>
> + */
> +#include <linux/bits.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#include <linux/gpio/driver.h>
> +
> +#include <linux/mfd/da9062/core.h>
> +#include <linux/mfd/da9062/registers.h>
> +
> +/*
> + * We need this get the gpio_desc from a <gpio_chip,offset> tuple to decide if
> + * the gpio is active low without a vendor specific dt-binding.
> + */
> +#include <../gpio/gpiolib.h>
> +
> +#define DA9062_TYPE(offset)		(4 * (offset % 2))
> +#define DA9062_PIN_SHIFT(offset)	(4 * (offset % 2))
> +#define DA9062_PIN_ALTERNATE		0x00 /* gpio alternate mode */
> +#define DA9062_PIN_GPI			0x01 /* gpio in */
> +#define DA9062_PIN_GPO_OD		0x02 /* gpio out open-drain */
> +#define DA9062_PIN_GPO_PP		0x03 /* gpio out push-pull */
> +#define DA9062_GPIO_NUM			5
> +
> +struct da9062_pctl {
> +	struct da9062 *da9062;
> +	struct gpio_chip gc;
> +	unsigned int pin_config[DA9062_GPIO_NUM];
> +};
> +
> +static int da9062_pctl_get_pin_mode(struct da9062_pctl *pctl,
> +				    unsigned int offset)
> +{
> +	struct regmap *regmap = pctl->da9062->regmap;
> +	int ret, val;
> +
> +	ret = regmap_read(regmap, DA9062AA_GPIO_0_1 + (offset >> 1), &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	val >>= DA9062_PIN_SHIFT(offset);
> +	val &= DA9062AA_GPIO0_PIN_MASK;
> +
> +	return val;
> +}
> +
> +static int da9062_pctl_set_pin_mode(struct da9062_pctl *pctl,
> +				    unsigned int offset, unsigned int mode_req)
> +{
> +	struct regmap *regmap = pctl->da9062->regmap;
> +	unsigned int mode = mode_req;
> +	unsigned int mask;
> +	int ret;
> +
> +	mode &= DA9062AA_GPIO0_PIN_MASK;
> +	mode <<= DA9062_PIN_SHIFT(offset);
> +	mask = DA9062AA_GPIO0_PIN_MASK << DA9062_PIN_SHIFT(offset);
> +
> +	ret = regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >> 1),
> +				 mask, mode);
> +	if (!ret)
> +		pctl->pin_config[offset] = mode_req;
> +
> +	return ret;
> +}
> +
> +static int da9062_gpio_get(struct gpio_chip *gc, unsigned int offset)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	struct regmap *regmap = pctl->da9062->regmap;
> +	int gpio_mode, val;
> +	int ret;
> +
> +	gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
> +	if (gpio_mode < 0)
> +		return gpio_mode;
> +
> +	switch (gpio_mode) {
> +	case DA9062_PIN_ALTERNATE:
> +		return -ENOTSUPP;
> +	case DA9062_PIN_GPI:
> +		ret = regmap_read(regmap, DA9062AA_STATUS_B, &val);
> +		if (ret < 0)
> +			return ret;
> +		break;
> +	case DA9062_PIN_GPO_OD:
> +	case DA9062_PIN_GPO_PP:
> +		ret = regmap_read(regmap, DA9062AA_GPIO_MODE0_4, &val);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return !!(val & BIT(offset));
> +}
> +
> +static void da9062_gpio_set(struct gpio_chip *gc, unsigned int offset,
> +			    int value)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	struct regmap *regmap = pctl->da9062->regmap;
> +
> +	regmap_update_bits(regmap, DA9062AA_GPIO_MODE0_4, BIT(offset),
> +			   value << offset);
> +}
> +
> +static int da9062_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	int gpio_mode;
> +
> +	gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
> +	if (gpio_mode < 0)
> +		return gpio_mode;
> +
> +	switch (gpio_mode) {
> +	case DA9062_PIN_ALTERNATE:
> +		return -ENOTSUPP;
> +	case DA9062_PIN_GPI:
> +		return GPIO_LINE_DIRECTION_IN;
> +	case DA9062_PIN_GPO_OD:
> +	case DA9062_PIN_GPO_PP:
> +		return GPIO_LINE_DIRECTION_OUT;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int da9062_gpio_direction_input(struct gpio_chip *gc,
> +				       unsigned int offset)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	struct regmap *regmap = pctl->da9062->regmap;
> +	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
> +	unsigned int gpi_type;
> +	int ret;
> +
> +	ret = da9062_pctl_set_pin_mode(pctl, offset, DA9062_PIN_GPI);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * If the gpio is active low we should set it in hw too. No worries
> +	 * about gpio_get() because we read and return the gpio-level. So the
> +	 * gpiolib active_low handling is still correct.
> +	 *
> +	 * 0 - active low, 1 - active high
> +	 */
> +	gpi_type = !gpiod_is_active_low(desc);
> +
> +	return regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >>
> 1),
> +				DA9062AA_GPIO0_TYPE_MASK <<
> DA9062_TYPE(offset),
> +				gpi_type << DA9062_TYPE(offset));
> +}
> +
> +static int da9062_gpio_direction_output(struct gpio_chip *gc,
> +					unsigned int offset, int value)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	unsigned int pin_config = pctl->pin_config[offset];
> +	int ret;
> +
> +	ret = da9062_pctl_set_pin_mode(pctl, offset, pin_config);
> +	if (ret)
> +		return ret;
> +
> +	da9062_gpio_set(gc, offset, value);
> +
> +	return 0;
> +}
> +
> +static int da9062_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
> +				  unsigned long config)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	struct regmap *regmap = pctl->da9062->regmap;
> +	int gpio_mode;
> +
> +	/*
> +	 * We need to meet the following restrictions [1, Figure 18]:
> +	 * - PIN_CONFIG_BIAS_PULL_DOWN -> only allowed if the pin is used as
> +	 *				  gpio input
> +	 * - PIN_CONFIG_BIAS_PULL_UP   -> only allowed if the pin is used as
> +	 *				  gpio output open-drain.
> +	 */
> +
> +	switch (pinconf_to_config_param(config)) {
> +	case PIN_CONFIG_BIAS_DISABLE:
> +		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
> +					  BIT(offset), 0);
> +	case PIN_CONFIG_BIAS_PULL_DOWN:
> +		gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
> +		if (gpio_mode < 0)
> +			return -EINVAL;
> +		else if (gpio_mode != DA9062_PIN_GPI)
> +			return -ENOTSUPP;
> +		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
> +					  BIT(offset), BIT(offset));
> +	case PIN_CONFIG_BIAS_PULL_UP:
> +		gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
> +		if (gpio_mode < 0)
> +			return -EINVAL;
> +		else if (gpio_mode != DA9062_PIN_GPO_OD)
> +			return -ENOTSUPP;
> +		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
> +					  BIT(offset), BIT(offset));
> +	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
> +		return da9062_pctl_set_pin_mode(pctl, offset,
> +						DA9062_PIN_GPO_OD);
> +	case PIN_CONFIG_DRIVE_PUSH_PULL:
> +		return da9062_pctl_set_pin_mode(pctl, offset,
> +						DA9062_PIN_GPO_PP);
> +	default:
> +		return -ENOTSUPP;
> +	}
> +}
> +
> +static int da9062_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
> +{
> +	struct da9062_pctl *pctl = gpiochip_get_data(gc);
> +	struct da9062 *da9062 = pctl->da9062;
> +
> +	return regmap_irq_get_virq(da9062->regmap_irq,
> +				   DA9062_IRQ_GPI0 + offset);
> +}
> +
> +static const struct gpio_chip reference_gc = {
> +	.owner = THIS_MODULE,
> +	.get = da9062_gpio_get,
> +	.set = da9062_gpio_set,
> +	.get_direction = da9062_gpio_get_direction,
> +	.direction_input = da9062_gpio_direction_input,
> +	.direction_output = da9062_gpio_direction_output,
> +	.set_config = da9062_gpio_set_config,
> +	.to_irq = da9062_gpio_to_irq,
> +	.can_sleep = true,
> +	.ngpio = DA9062_GPIO_NUM,
> +	.base = -1,
> +};
> +
> +static int da9062_pctl_probe(struct platform_device *pdev)
> +{
> +	struct device *parent = pdev->dev.parent;
> +	struct da9062_pctl *pctl;
> +	int i;
> +
> +	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
> +	if (!pctl)
> +		return -ENOMEM;
> +
> +	pctl->da9062 = dev_get_drvdata(parent);
> +	if (!pctl->da9062)
> +		return -EINVAL;
> +
> +	if (!device_property_present(parent, "gpio-controller"))
> +		return 0;
> +
> +	for (i = 0; i < ARRAY_SIZE(pctl->pin_config); i++)
> +		pctl->pin_config[i] = DA9062_PIN_GPO_PP;
> +
> +	/*
> +	 * Currently the driver handles only the GPIO support. The
> +	 * pinctrl/pinmux support can be added later if needed.
> +	 */
> +	pctl->gc = reference_gc;
> +	pctl->gc.label = dev_name(&pdev->dev);
> +	pctl->gc.parent = &pdev->dev;
> +#ifdef CONFIG_OF_GPIO
> +	pctl->gc.of_node = parent->of_node;
> +#endif
> +
> +	platform_set_drvdata(pdev, pctl);
> +
> +	return devm_gpiochip_add_data(&pdev->dev, &pctl->gc, pctl);
> +}
> +
> +static struct platform_driver da9062_pctl_driver = {
> +	.probe = da9062_pctl_probe,
> +	.driver = {
> +		.name	= "da9062-gpio",
> +	},
> +};
> +module_platform_driver(da9062_pctl_driver);
> +
> +MODULE_AUTHOR("Marco Felsch <kernel@xxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("DA9062 PMIC pinctrl and GPIO Driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:da9062-gpio");
> --
> 2.20.1