gpio: bd70528 Drop BD70528 support

The only known BD70528 use-cases are such that the PMIC is controlled
from separate MCU which is not running Linux. I am not aware of
any Linux driver users. Furthermore, it seems there is no demand for
this IC. Let's ease the maintenance burden and drop the driver. We can
always add it back if there is sudden need for it.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/4eff6bd5eff8afc137dd8c1697cb5c6b2e3aacd2.1637066805.git.matti.vaittinen@fi.rohmeurope.com

drivers/gpio/Kconfig

@@ -1132,17 +1132,6 @@ config GPIO_ARIZONA
 	help
 	  Support for GPIOs on Wolfson Arizona class devices.
 
-config GPIO_BD70528
-	tristate "ROHM BD70528 GPIO support"
-	depends on MFD_ROHM_BD70528
-	help
-	  Support for GPIOs on ROHM BD70528 PMIC. There are four GPIOs
-	  available on the ROHM PMIC in total. The GPIOs can also
-	  generate interrupts.
-
-	  This driver can also be built as a module. If so, the module
-	  will be called gpio-bd70528.
-
 config GPIO_BD71815
 	tristate "ROHM BD71815 PMIC GPIO support"
 	depends on MFD_ROHM_BD71828

drivers/gpio/Makefile

@@ -38,7 +38,6 @@ obj-$(CONFIG_GPIO_ASPEED_SGPIO)		+= gpio-aspeed-sgpio.o
 obj-$(CONFIG_GPIO_ATH79)		+= gpio-ath79.o
 obj-$(CONFIG_GPIO_BCM_KONA)		+= gpio-bcm-kona.o
 obj-$(CONFIG_GPIO_BCM_XGS_IPROC)	+= gpio-xgs-iproc.o
-obj-$(CONFIG_GPIO_BD70528)		+= gpio-bd70528.o
 obj-$(CONFIG_GPIO_BD71815)		+= gpio-bd71815.o
 obj-$(CONFIG_GPIO_BD71828)		+= gpio-bd71828.o
 obj-$(CONFIG_GPIO_BD9571MWV)		+= gpio-bd9571mwv.o

drivers/gpio/gpio-bd70528.c

-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2018 ROHM Semiconductors
-// gpio-bd70528.c ROHM BD70528MWV gpio driver
-
-#include <linux/gpio/driver.h>
-#include <linux/mfd/rohm-bd70528.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/regmap.h>
-
-#define GPIO_IN_REG(offset) (BD70528_REG_GPIO1_IN + (offset) * 2)
-#define GPIO_OUT_REG(offset) (BD70528_REG_GPIO1_OUT + (offset) * 2)
-
-struct bd70528_gpio {
-	struct regmap *regmap;
-	struct device *dev;
-	struct gpio_chip gpio;
-};
-
-static int bd70528_set_debounce(struct bd70528_gpio *bdgpio,
-				unsigned int offset, unsigned int debounce)
-{
-	u8 val;
-
-	switch (debounce) {
-	case 0:
-		val = BD70528_DEBOUNCE_DISABLE;
-		break;
-	case 1 ... 15000:
-		val = BD70528_DEBOUNCE_15MS;
-		break;
-	case 15001 ... 30000:
-		val = BD70528_DEBOUNCE_30MS;
-		break;
-	case 30001 ... 50000:
-		val = BD70528_DEBOUNCE_50MS;
-		break;
-	default:
-		dev_err(bdgpio->dev,
-			"Invalid debounce value %u\n", debounce);
-		return -EINVAL;
-	}
-	return regmap_update_bits(bdgpio->regmap, GPIO_IN_REG(offset),
-				 BD70528_DEBOUNCE_MASK, val);
-}
-
-static int bd70528_get_direction(struct gpio_chip *chip, unsigned int offset)
-{
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-	int val, ret;
-
-	/* Do we need to do something to IRQs here? */
-	ret = regmap_read(bdgpio->regmap, GPIO_OUT_REG(offset), &val);
-	if (ret) {
-		dev_err(bdgpio->dev, "Could not read gpio direction\n");
-		return ret;
-	}
-	if (val & BD70528_GPIO_OUT_EN_MASK)
-		return GPIO_LINE_DIRECTION_OUT;
-
-	return GPIO_LINE_DIRECTION_IN;
-}
-
-static int bd70528_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
-				   unsigned long config)
-{
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-
-	switch (pinconf_to_config_param(config)) {
-	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
-		return regmap_update_bits(bdgpio->regmap,
-					  GPIO_OUT_REG(offset),
-					  BD70528_GPIO_DRIVE_MASK,
-					  BD70528_GPIO_OPEN_DRAIN);
-		break;
-	case PIN_CONFIG_DRIVE_PUSH_PULL:
-		return regmap_update_bits(bdgpio->regmap,
-					  GPIO_OUT_REG(offset),
-					  BD70528_GPIO_DRIVE_MASK,
-					  BD70528_GPIO_PUSH_PULL);
-		break;
-	case PIN_CONFIG_INPUT_DEBOUNCE:
-		return bd70528_set_debounce(bdgpio, offset,
-					    pinconf_to_config_argument(config));
-		break;
-	default:
-		break;
-	}
-	return -ENOTSUPP;
-}
-
-static int bd70528_direction_input(struct gpio_chip *chip, unsigned int offset)
-{
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-
-	/* Do we need to do something to IRQs here? */
-	return regmap_update_bits(bdgpio->regmap, GPIO_OUT_REG(offset),
-				 BD70528_GPIO_OUT_EN_MASK,
-				 BD70528_GPIO_OUT_DISABLE);
-}
-
-static void bd70528_gpio_set(struct gpio_chip *chip, unsigned int offset,
-			     int value)
-{
-	int ret;
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-	u8 val = (value) ? BD70528_GPIO_OUT_HI : BD70528_GPIO_OUT_LO;
-
-	ret = regmap_update_bits(bdgpio->regmap, GPIO_OUT_REG(offset),
-				 BD70528_GPIO_OUT_MASK, val);
-	if (ret)
-		dev_err(bdgpio->dev, "Could not set gpio to %d\n", value);
-}
-
-static int bd70528_direction_output(struct gpio_chip *chip, unsigned int offset,
-				    int value)
-{
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-
-	bd70528_gpio_set(chip, offset, value);
-	return regmap_update_bits(bdgpio->regmap, GPIO_OUT_REG(offset),
-				 BD70528_GPIO_OUT_EN_MASK,
-				 BD70528_GPIO_OUT_ENABLE);
-}
-
-#define GPIO_IN_STATE_MASK(offset) (BD70528_GPIO_IN_STATE_BASE << (offset))
-
-static int bd70528_gpio_get_o(struct bd70528_gpio *bdgpio, unsigned int offset)
-{
-	int ret;
-	unsigned int val;
-
-	ret = regmap_read(bdgpio->regmap, GPIO_OUT_REG(offset), &val);
-	if (!ret)
-		ret = !!(val & BD70528_GPIO_OUT_MASK);
-	else
-		dev_err(bdgpio->dev, "GPIO (out) state read failed\n");
-
-	return ret;
-}
-
-static int bd70528_gpio_get_i(struct bd70528_gpio *bdgpio, unsigned int offset)
-{
-	unsigned int val;
-	int ret;
-
-	ret = regmap_read(bdgpio->regmap, BD70528_REG_GPIO_STATE, &val);
-
-	if (!ret)
-		ret = !(val & GPIO_IN_STATE_MASK(offset));
-	else
-		dev_err(bdgpio->dev, "GPIO (in) state read failed\n");
-
-	return ret;
-}
-
-static int bd70528_gpio_get(struct gpio_chip *chip, unsigned int offset)
-{
-	int ret;
-	struct bd70528_gpio *bdgpio = gpiochip_get_data(chip);
-
-	/*
-	 * There is a race condition where someone might be changing the
-	 * GPIO direction after we get it but before we read the value. But
-	 * application design where GPIO direction may be changed just when
-	 * we read GPIO value would be pointless as reader could not know
-	 * whether the returned high/low state is caused by input or output.
-	 * Or then there must be other ways to mitigate the issue. Thus
-	 * locking would make no sense.
-	 */
-	ret = bd70528_get_direction(chip, offset);
-	if (ret == GPIO_LINE_DIRECTION_OUT)
-		ret = bd70528_gpio_get_o(bdgpio, offset);
-	else if (ret == GPIO_LINE_DIRECTION_IN)
-		ret = bd70528_gpio_get_i(bdgpio, offset);
-	else
-		dev_err(bdgpio->dev, "failed to read GPIO direction\n");
-
-	return ret;
-}
-
-static int bd70528_probe(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct bd70528_gpio *bdgpio;
-	int ret;
-
-	bdgpio = devm_kzalloc(dev, sizeof(*bdgpio), GFP_KERNEL);
-	if (!bdgpio)
-		return -ENOMEM;
-	bdgpio->dev = dev;
-	bdgpio->gpio.parent = dev->parent;
-	bdgpio->gpio.label = "bd70528-gpio";
-	bdgpio->gpio.owner = THIS_MODULE;
-	bdgpio->gpio.get_direction = bd70528_get_direction;
-	bdgpio->gpio.direction_input = bd70528_direction_input;
-	bdgpio->gpio.direction_output = bd70528_direction_output;
-	bdgpio->gpio.set_config = bd70528_gpio_set_config;
-	bdgpio->gpio.can_sleep = true;
-	bdgpio->gpio.get = bd70528_gpio_get;
-	bdgpio->gpio.set = bd70528_gpio_set;
-	bdgpio->gpio.ngpio = 4;
-	bdgpio->gpio.base = -1;
-#ifdef CONFIG_OF_GPIO
-	bdgpio->gpio.of_node = dev->parent->of_node;
-#endif
-	bdgpio->regmap = dev_get_regmap(dev->parent, NULL);
-	if (!bdgpio->regmap)
-		return -ENODEV;
-
-	ret = devm_gpiochip_add_data(dev, &bdgpio->gpio, bdgpio);
-	if (ret)
-		dev_err(dev, "gpio_init: Failed to add bd70528-gpio\n");
-
-	return ret;
-}
-
-static struct platform_driver bd70528_gpio = {
-	.driver = {
-		.name = "bd70528-gpio"
-	},
-	.probe = bd70528_probe,
-};
-
-module_platform_driver(bd70528_gpio);
-
-MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
-MODULE_DESCRIPTION("BD70528 voltage regulator driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:bd70528-gpio");