diff options
Diffstat (limited to 'drivers/gpio/gpio-mlxbf.c')
| -rw-r--r-- | drivers/gpio/gpio-mlxbf.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mlxbf.c b/drivers/gpio/gpio-mlxbf.c new file mode 100644 index 0000000000..1fa9973f55 --- /dev/null +++ b/drivers/gpio/gpio-mlxbf.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/acpi.h> +#include <linux/bitops.h> +#include <linux/device.h> +#include <linux/gpio/driver.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/resource.h> +#include <linux/types.h> + +/* Number of pins on BlueField */ +#define MLXBF_GPIO_NR 54 + +/* Pad Electrical Controls. */ +#define MLXBF_GPIO_PAD_CONTROL_FIRST_WORD 0x0700 +#define MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD 0x0708 +#define MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD 0x0710 +#define MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD 0x0718 + +#define MLXBF_GPIO_PIN_DIR_I 0x1040 +#define MLXBF_GPIO_PIN_DIR_O 0x1048 +#define MLXBF_GPIO_PIN_STATE 0x1000 +#define MLXBF_GPIO_SCRATCHPAD 0x20 + +#ifdef CONFIG_PM +struct mlxbf_gpio_context_save_regs { + u64 scratchpad; + u64 pad_control[MLXBF_GPIO_NR]; + u64 pin_dir_i; + u64 pin_dir_o; +}; +#endif + +/* Device state structure. */ +struct mlxbf_gpio_state { + struct gpio_chip gc; + + /* Memory Address */ + void __iomem *base; + +#ifdef CONFIG_PM + struct mlxbf_gpio_context_save_regs csave_regs; +#endif +}; + +static int mlxbf_gpio_probe(struct platform_device *pdev) +{ + struct mlxbf_gpio_state *gs; + struct device *dev = &pdev->dev; + struct gpio_chip *gc; + int ret; + + gs = devm_kzalloc(&pdev->dev, sizeof(*gs), GFP_KERNEL); + if (!gs) + return -ENOMEM; + + gs->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(gs->base)) + return PTR_ERR(gs->base); + + gc = &gs->gc; + ret = bgpio_init(gc, dev, 8, + gs->base + MLXBF_GPIO_PIN_STATE, + NULL, + NULL, + gs->base + MLXBF_GPIO_PIN_DIR_O, + gs->base + MLXBF_GPIO_PIN_DIR_I, + 0); + if (ret) + return -ENODEV; + + gc->owner = THIS_MODULE; + gc->ngpio = MLXBF_GPIO_NR; + + ret = devm_gpiochip_add_data(dev, &gs->gc, gs); + if (ret) { + dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n"); + return ret; + } + + platform_set_drvdata(pdev, gs); + dev_info(&pdev->dev, "registered Mellanox BlueField GPIO"); + return 0; +} + +#ifdef CONFIG_PM +static int mlxbf_gpio_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev); + + gs->csave_regs.scratchpad = readq(gs->base + MLXBF_GPIO_SCRATCHPAD); + gs->csave_regs.pad_control[0] = + readq(gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD); + gs->csave_regs.pad_control[1] = + readq(gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD); + gs->csave_regs.pad_control[2] = + readq(gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD); + gs->csave_regs.pad_control[3] = + readq(gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD); + gs->csave_regs.pin_dir_i = readq(gs->base + MLXBF_GPIO_PIN_DIR_I); + gs->csave_regs.pin_dir_o = readq(gs->base + MLXBF_GPIO_PIN_DIR_O); + + return 0; +} + +static int mlxbf_gpio_resume(struct platform_device *pdev) +{ + struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev); + + writeq(gs->csave_regs.scratchpad, gs->base + MLXBF_GPIO_SCRATCHPAD); + writeq(gs->csave_regs.pad_control[0], + gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD); + writeq(gs->csave_regs.pad_control[1], + gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD); + writeq(gs->csave_regs.pad_control[2], + gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD); + writeq(gs->csave_regs.pad_control[3], + gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD); + writeq(gs->csave_regs.pin_dir_i, gs->base + MLXBF_GPIO_PIN_DIR_I); + writeq(gs->csave_regs.pin_dir_o, gs->base + MLXBF_GPIO_PIN_DIR_O); + + return 0; +} +#endif + +static const struct acpi_device_id __maybe_unused mlxbf_gpio_acpi_match[] = { + { "MLNXBF02", 0 }, + {} +}; +MODULE_DEVICE_TABLE(acpi, mlxbf_gpio_acpi_match); + +static struct platform_driver mlxbf_gpio_driver = { + .driver = { + .name = "mlxbf_gpio", + .acpi_match_table = ACPI_PTR(mlxbf_gpio_acpi_match), + }, + .probe = mlxbf_gpio_probe, +#ifdef CONFIG_PM + .suspend = mlxbf_gpio_suspend, + .resume = mlxbf_gpio_resume, +#endif +}; + +module_platform_driver(mlxbf_gpio_driver); + +MODULE_DESCRIPTION("Mellanox BlueField GPIO Driver"); +MODULE_AUTHOR("Mellanox Technologies"); +MODULE_LICENSE("GPL"); |