[PATCH v5 1/1] gpio: add driver for Mellanox BlueField GPIO controller

From: Shravan Kumar Ramani
Date: Mon Mar 25 2019 - 14:30:59 EST


This patch adds support for the GPIO controller used by Mellanox
BlueField SOCs.

Reviewed-by: David Woods <dwoods@xxxxxxxxxxxx>
Signed-off-by: Shravan Kumar Ramani <sramani@xxxxxxxxxxxx>
---
drivers/gpio/Kconfig | 7 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-mlxbf.c | 154 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 162 insertions(+)
create mode 100644 drivers/gpio/gpio-mlxbf.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 3f50526..0d9ddff 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1316,6 +1316,13 @@ config GPIO_MERRIFIELD
help
Say Y here to support Intel Merrifield GPIO.

+config GPIO_MLXBF
+ tristate "Mellanox BlueField SoC GPIO"
+ depends on (MELLANOX_PLATFORM && ARM64 && ACPI) || COMPILE_TEST
+ select GPIO_GENERIC
+ help
+ Say Y here if you want GPIO support on Mellanox BlueField SoC.
+
config GPIO_ML_IOH
tristate "OKI SEMICONDUCTOR ML7213 IOH GPIO support"
depends on X86 || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 54d5527..db8d854 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -85,6 +85,7 @@ obj-$(CONFIG_GPIO_MENZ127) += gpio-menz127.o
obj-$(CONFIG_GPIO_MERRIFIELD) += gpio-merrifield.o
obj-$(CONFIG_GPIO_MC33880) += gpio-mc33880.o
obj-$(CONFIG_GPIO_MC9S08DZ60) += gpio-mc9s08dz60.o
+obj-$(CONFIG_GPIO_MLXBF) += gpio-mlxbf.o
obj-$(CONFIG_GPIO_ML_IOH) += gpio-ml-ioh.o
obj-$(CONFIG_GPIO_MM_LANTIQ) += gpio-mm-lantiq.o
obj-$(CONFIG_GPIO_MOCKUP) += gpio-mockup.o
diff --git a/drivers/gpio/gpio-mlxbf.c b/drivers/gpio/gpio-mlxbf.c
new file mode 100644
index 0000000..42087c6
--- /dev/null
+++ b/drivers/gpio/gpio-mlxbf.c
@@ -0,0 +1,154 @@
+// 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>
+#include <linux/version.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;
+ struct resource *res;
+ int ret;
+
+ gs = devm_kzalloc(&pdev->dev, sizeof(*gs), GFP_KERNEL);
+ if (!gs)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ gs->base = devm_ioremap_resource(&pdev->dev, res);
+ 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 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");
--
2.1.2