On Fri, Aug 9, 2024 at 4:52 PM Thomas Richard <thomas.richard@xxxxxxxxxxx> wrote: > > Add gpio support for the Congatec Board Controller. > > Signed-off-by: Thomas Richard <thomas.richard@xxxxxxxxxxx> > --- > drivers/gpio/Kconfig | 10 +++ > drivers/gpio/Makefile | 1 + > drivers/gpio/gpio-cgbc.c | 203 +++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 214 insertions(+) > > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig > index 58f43bcced7c..ce77bad40087 100644 > --- a/drivers/gpio/Kconfig > +++ b/drivers/gpio/Kconfig > @@ -233,6 +233,16 @@ config GPIO_CADENCE > help > Say yes here to enable support for Cadence GPIO controller. > > +config GPIO_CGBC > + tristate "Congatec Board Controller GPIO support" > + depends on MFD_CGBC > + help > + Select this option to enable GPIO support for the Congatec Board > + Controller. > + > + This driver can also be built as a module. If so, the module will be > + called gpio-cgbc. > + > config GPIO_CLPS711X > tristate "CLPS711X GPIO support" > depends on ARCH_CLPS711X || COMPILE_TEST > diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile > index 64dd6d9d730d..3a96e3c27a2d 100644 > --- a/drivers/gpio/Makefile > +++ b/drivers/gpio/Makefile > @@ -44,6 +44,7 @@ obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o > obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o > obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o > obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o > +obj-$(CONFIG_GPIO_CGBC) += gpio-cgbc.o > obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o > obj-$(CONFIG_GPIO_SNPS_CREG) += gpio-creg-snps.o > obj-$(CONFIG_GPIO_CROS_EC) += gpio-cros-ec.o > diff --git a/drivers/gpio/gpio-cgbc.c b/drivers/gpio/gpio-cgbc.c > new file mode 100644 > index 000000000000..6da50c794872 > --- /dev/null > +++ b/drivers/gpio/gpio-cgbc.c > @@ -0,0 +1,203 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Congatec Board Controller GPIO driver > + * > + * Copyright (C) 2024 Bootlin > + * Author: Thomas Richard <thomas.richard@xxxxxxxxxxx> > + */ > + > +#include <linux/gpio/driver.h> > +#include <linux/mfd/cgbc.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/platform_device.h> > + > +#define CGBC_GPIO_NGPIO 14 > + > +#define CGBC_GPIO_CMD_GET 0x64 > +#define CGBC_GPIO_CMD_SET 0x65 > +#define CGBC_GPIO_CMD_DIR_GET 0x66 > +#define CGBC_GPIO_CMD_DIR_SET 0x67 > + > +struct cgbc_gpio_data { > + struct gpio_chip chip; > + struct cgbc_device_data *cgbc; > + struct mutex lock; > +}; > + > +static int cgbc_gpio_cmd(struct cgbc_device_data *cgbc, > + u8 cmd0, u8 cmd1, u8 cmd2, u8 *value) > +{ > + u8 cmd[3] = {cmd0, cmd1, cmd2}; > + > + return cgbc_command(cgbc, cmd, sizeof(cmd), value, 1, NULL); > +} > + > +static int cgbc_gpio_get(struct gpio_chip *chip, unsigned int offset) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + struct cgbc_device_data *cgbc = gpio->cgbc; > + int ret; > + u8 val; > + Can you use scoped_guard() here and elsewhere? > + mutex_lock(&gpio->lock); > + > + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_GET, (offset > 7) ? 1 : 0, 0, &val); > + > + mutex_unlock(&gpio->lock); > + > + offset %= 8; > + > + if (ret) > + return ret; > + else > + return (int)(val & (u8)BIT(offset)); > +} > + > +static void __cgbc_gpio_set(struct gpio_chip *chip, > + unsigned int offset, int value) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + struct cgbc_device_data *cgbc = gpio->cgbc; > + u8 val; > + int ret; > + > + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_GET, (offset > 7) ? 1 : 0, 0, &val); > + if (ret) > + return; > + > + if (value) > + val |= BIT(offset % 8); > + else > + val &= ~((u8)BIT(offset % 8)); > + > + cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_SET, (offset > 7) ? 1 : 0, val, &val); > +} > + > +static void cgbc_gpio_set(struct gpio_chip *chip, > + unsigned int offset, int value) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + > + mutex_lock(&gpio->lock); > + __cgbc_gpio_set(chip, offset, value); > + mutex_unlock(&gpio->lock); > +} > + > +static int cgbc_gpio_direction_set(struct gpio_chip *chip, > + unsigned int offset, int direction) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + struct cgbc_device_data *cgbc = gpio->cgbc; > + int ret; > + u8 val; > + > + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_GET, (offset > 7) ? 1 : 0, 0, &val); > + if (ret) > + goto end; > + > + if (direction == GPIO_LINE_DIRECTION_IN) > + val &= ~((u8)BIT(offset % 8)); > + else > + val |= BIT(offset % 8); > + > + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_SET, (offset > 7) ? 1 : 0, val, &val); > + > +end: > + return ret; > +} > + > +static int cgbc_gpio_direction_input(struct gpio_chip *chip, > + unsigned int offset) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + int ret; > + > + mutex_lock(&gpio->lock); > + ret = cgbc_gpio_direction_set(chip, offset, GPIO_LINE_DIRECTION_IN); > + mutex_unlock(&gpio->lock); > + > + return ret; > +} > + > +static int cgbc_gpio_direction_output(struct gpio_chip *chip, > + unsigned int offset, int value) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + int ret; > + > + mutex_lock(&gpio->lock); > + __cgbc_gpio_set(chip, offset, value); > + ret = cgbc_gpio_direction_set(chip, offset, GPIO_LINE_DIRECTION_OUT); > + mutex_unlock(&gpio->lock); > + > + return ret; > +} > + > +static int cgbc_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) > +{ > + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); > + struct cgbc_device_data *cgbc = gpio->cgbc; > + int ret; > + u8 val; > + > + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_GET, (offset > 7) ? 1 : 0, 0, &val); > + if (ret) > + return ret; > + > + if (val & BIT(offset % 8)) > + return GPIO_LINE_DIRECTION_OUT; > + else > + return GPIO_LINE_DIRECTION_IN; > +} > + > +static int cgbc_gpio_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct cgbc_device_data *cgbc = dev_get_drvdata(dev->parent); > + struct cgbc_gpio_data *gpio; > + struct gpio_chip *chip; > + int ret; > + > + gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL); > + if (!gpio) > + return -ENOMEM; > + > + gpio->cgbc = cgbc; > + > + platform_set_drvdata(pdev, gpio); > + > + chip = &gpio->chip; > + chip->label = dev_name(&pdev->dev); > + chip->owner = THIS_MODULE; > + chip->parent = dev; > + chip->base = -1; > + chip->direction_input = cgbc_gpio_direction_input; > + chip->direction_output = cgbc_gpio_direction_output; > + chip->get_direction = cgbc_gpio_get_direction; > + chip->get = cgbc_gpio_get; > + chip->set = cgbc_gpio_set; > + chip->ngpio = CGBC_GPIO_NGPIO; > + > + mutex_init(&gpio->lock); Please use devm_mutex_init() so that it gets cleaned up at exit. It's not strictly necessary but helps with lock debugging. > + > + ret = devm_gpiochip_add_data(dev, chip, gpio); > + if (ret) > + return dev_err_probe(dev, ret, "Could not register GPIO chip\n"); > + > + return 0; > +} > + > +static struct platform_driver cgbc_gpio_driver = { > + .driver = { > + .name = "cgbc-gpio", > + }, > + .probe = cgbc_gpio_probe, > +}; > + > +module_platform_driver(cgbc_gpio_driver); > + > +MODULE_DESCRIPTION("Congatec Board Controller GPIO Driver"); > +MODULE_AUTHOR("Thomas Richard <thomas.richard@xxxxxxxxxxx>"); > +MODULE_LICENSE("GPL"); > +MODULE_ALIAS("platform:cgbc-gpio"); > > -- > 2.39.2 > Bart