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

Reviewed-by: David Woods <dwo...@mellanox.com>
Signed-off-by: Shravan Kumar Ramani <sram...@mellanox.com>
---
 drivers/gpio/Kconfig      |   7 ++
 drivers/gpio/Makefile     |   1 +
 drivers/gpio/gpio-mlxbf.c | 287 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 295 insertions(+)
 create mode 100644 drivers/gpio/gpio-mlxbf.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b5a2845..2bebe92 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1292,6 +1292,13 @@ 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 37628f8..8d54279 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -83,6 +83,7 @@ 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..e5c50db
--- /dev/null
+++ b/drivers/gpio/gpio-mlxbf.c
@@ -0,0 +1,287 @@
+// 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/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/resource.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/version.h>
+
+/* Number of pins on BlueField */
+#define MLXBF_GPIO_NR 54
+
+/* Pad Electrical Controls. */
+#define GPIO_PAD_CONTROL__FIRST_WORD 0x0700
+#define GPIO_PAD_CONTROL_1__FIRST_WORD 0x0708
+#define GPIO_PAD_CONTROL_2__FIRST_WORD 0x0710
+#define GPIO_PAD_CONTROL_3__FIRST_WORD 0x0718
+
+#define GPIO_PIN_DIR_I 0x1040
+#define GPIO_PIN_DIR_O 0x1048
+#define GPIO_PIN_STATE 0x1000
+#define GPIO_SCRATCHPAD 0x20
+
+#ifdef CONFIG_PM
+struct bluefield_context_save_regs {
+       u64 gpio_scratchpad;
+       u64 gpio_pad_control[MLXBF_GPIO_NR];
+       u64 gpio_pin_dir_i;
+       u64 gpio_pin_dir_o;
+};
+#endif
+
+/* Device state structure. */
+struct gpio_state {
+       struct list_head node;
+       struct platform_device *pdev;
+
+       struct gpio_chip gc;
+
+       /* Must hold this lock to modify shared data. */
+       spinlock_t lock;
+
+       /* Memory Address */
+       void __iomem *dc_base;
+
+#ifdef CONFIG_PM
+       struct bluefield_context_save_regs csave_regs;
+#endif
+};
+
+/* GPIO driver set input pins */
+static int gpio_bf_set_input(struct gpio_chip *chip, unsigned int offset)
+{
+       struct gpio_state *gs = gpiochip_get_data(chip);
+       u64 in;
+       u64 out;
+
+       if (offset > MLXBF_GPIO_NR - 1) {
+               dev_err(chip->parent, "gpio input pins: Invalid offset %d\n",
+                       offset);
+               return -EINVAL;
+       }
+
+       out = readq(gs->dc_base + GPIO_PIN_DIR_O);
+       in = readq(gs->dc_base + GPIO_PIN_DIR_I);
+
+       writeq(out & ~BIT(offset), gs->dc_base + GPIO_PIN_DIR_O);
+       writeq(in | BIT(offset), gs->dc_base + GPIO_PIN_DIR_I);
+
+       return 0;
+}
+
+/* GPIO driver set output pins */
+static int gpio_bf_set_output(struct gpio_chip *chip, unsigned int offset)
+{
+       struct gpio_state *gs = gpiochip_get_data(chip);
+       u64 in;
+       u64 out;
+
+       if (offset > MLXBF_GPIO_NR - 1) {
+               dev_err(chip->parent, "gpio output pins: Invalid offset %d\n",
+                       offset);
+               return -EINVAL;
+       }
+
+       out = readq(gs->dc_base + GPIO_PIN_DIR_O);
+       in = readq(gs->dc_base + GPIO_PIN_DIR_I);
+
+       writeq(out | BIT(offset), gs->dc_base + GPIO_PIN_DIR_O);
+       writeq(in & ~BIT(offset), gs->dc_base + GPIO_PIN_DIR_I);
+
+       return 0;
+}
+
+/* GPIO driver output direction */
+static int gpio_bf_set_output_lock(struct gpio_chip *chip,
+                                  unsigned int offset, int value)
+{
+       struct gpio_state *gs = gpiochip_get_data(chip);
+
+       spin_lock(&gs->lock);
+       gpio_bf_set_output(chip, offset);
+       spin_unlock(&gs->lock);
+
+       return 0;
+}
+
+/* GPIO driver input direction */
+static int gpio_bf_set_input_lock(struct gpio_chip *chip, unsigned int offset)
+{
+       struct gpio_state *gs = gpiochip_get_data(chip);
+
+       spin_lock(&gs->lock);
+       gpio_bf_set_input(chip, offset);
+       spin_unlock(&gs->lock);
+
+       return 0;
+}
+
+/* GPIO driver read routine. */
+static int gpio_bf_get(struct gpio_chip *chip, unsigned int offset)
+{
+       u64 value;
+       struct gpio_state *gs = gpiochip_get_data(chip);
+
+       value = readq(gs->dc_base + GPIO_PIN_STATE);
+
+       return (value >> offset) & 1;
+}
+
+/* GPIO driver write routine. */
+static void gpio_bf_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+       u64 data;
+       struct gpio_state *gs = gpiochip_get_data(chip);
+
+       spin_lock(&gs->lock);
+       data = readq(gs->dc_base + GPIO_PIN_STATE);
+
+       if (value)
+               data |= BIT(offset);
+       else
+               data &= ~BIT(offset);
+       writeq(data, gs->dc_base + GPIO_PIN_STATE);
+       spin_unlock(&gs->lock);
+}
+
+/* GPIO driver initialization routine. */
+static int gpiodrv_probe(struct platform_device *pdev)
+{
+       struct gpio_state *gs;
+       struct device *dev = &pdev->dev;
+       struct gpio_chip *gc;
+       struct resource *dc_res;
+       int ret;
+
+       dc_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!dc_res)
+               return -EINVAL;
+
+       if (devm_request_mem_region(&pdev->dev, dc_res->start,
+                                   resource_size(dc_res), "gpiodrv") == NULL)
+               return -EBUSY;
+
+       gs = devm_kzalloc(&pdev->dev, sizeof(struct gpio_state), GFP_KERNEL);
+       if (!gs)
+               return -ENOMEM;
+
+       gs->dc_base = devm_ioremap(&pdev->dev, dc_res->start,
+                                  resource_size(dc_res));
+       if (!gs->dc_base)
+               return -ENOMEM;
+
+       gc = &gs->gc;
+       gc->direction_input = gpio_bf_set_input_lock;
+       gc->get = gpio_bf_get;
+       gc->direction_output = gpio_bf_set_output_lock;
+       gc->set = gpio_bf_set;
+       gc->label = dev_name(dev);
+       gc->parent = &pdev->dev;
+       gc->owner = THIS_MODULE;
+       gc->base = 0;
+       gc->ngpio = MLXBF_GPIO_NR;
+
+       ret = gpiochip_add_data(&gs->gc, gs);
+       if (ret) {
+               dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n");
+               goto err;
+       }
+
+       spin_lock_init(&gs->lock);
+       platform_set_drvdata(pdev, gs);
+       dev_info(&pdev->dev, "registered Mellanox BlueField GPIO");
+       return 0;
+
+err:
+       dev_err(&pdev->dev, "Probe, Failed\n");
+       return ret;
+}
+
+#ifdef CONFIG_PM
+/* GPIO driver suspend routine. */
+static int gpiodrv_suspend(struct platform_device *pdev, pm_message_t state)
+{
+       struct gpio_state *gs = platform_get_drvdata(pdev);
+
+       gs->csave_regs.gpio_scratchpad = readq(gs->dc_base + GPIO_SCRATCHPAD);
+       gs->csave_regs.gpio_pad_control[0] =
+               readq(gs->dc_base + GPIO_PAD_CONTROL__FIRST_WORD);
+       gs->csave_regs.gpio_pad_control[1] =
+               readq(gs->dc_base + GPIO_PAD_CONTROL_1__FIRST_WORD);
+       gs->csave_regs.gpio_pad_control[2] =
+               readq(gs->dc_base + GPIO_PAD_CONTROL_2__FIRST_WORD);
+       gs->csave_regs.gpio_pad_control[3] =
+               readq(gs->dc_base + GPIO_PAD_CONTROL_3__FIRST_WORD);
+       gs->csave_regs.gpio_pin_dir_i = readq(gs->dc_base + GPIO_PIN_DIR_I);
+       gs->csave_regs.gpio_pin_dir_o = readq(gs->dc_base + GPIO_PIN_DIR_O);
+
+       return 0;
+}
+
+/* GPIO driver resume routine. */
+static int gpiodrv_resume(struct platform_device *pdev)
+{
+       struct gpio_state *gs = platform_get_drvdata(pdev);
+
+       writeq(gs->csave_regs.gpio_scratchpad, gs->dc_base + GPIO_SCRATCHPAD);
+       writeq(gs->csave_regs.gpio_pad_control[0], gs->dc_base +
+              GPIO_PAD_CONTROL__FIRST_WORD);
+       writeq(gs->csave_regs.gpio_pad_control[1], gs->dc_base +
+              GPIO_PAD_CONTROL_1__FIRST_WORD);
+       writeq(gs->csave_regs.gpio_pad_control[2], gs->dc_base +
+              GPIO_PAD_CONTROL_2__FIRST_WORD);
+       writeq(gs->csave_regs.gpio_pad_control[3], gs->dc_base +
+              GPIO_PAD_CONTROL_3__FIRST_WORD);
+       writeq(gs->csave_regs.gpio_pin_dir_i, gs->dc_base + GPIO_PIN_DIR_I);
+       writeq(gs->csave_regs.gpio_pin_dir_o, gs->dc_base + GPIO_PIN_DIR_O);
+
+       return 0;
+}
+#endif
+
+/* GPIO driver exit routine. */
+static int gpiodrv_remove(struct platform_device *pdev)
+{
+       struct gpio_state *gs = platform_get_drvdata(pdev);
+
+       gpiochip_remove(&gs->gc);
+       iounmap(gs->dc_base);
+
+       return 0;
+}
+
+static const struct acpi_device_id gpiodrv_acpi_match[] = {
+       { "MLNXBF02", 0 },
+       {}
+};
+MODULE_DEVICE_TABLE(acpi, gpiodrv_acpi_match);
+
+static struct platform_driver gpiodrv_gpio_driver = {
+       .driver = {
+               .name = "gpiodrv",
+               .acpi_match_table = ACPI_PTR(gpiodrv_acpi_match),
+       },
+       .probe    = gpiodrv_probe,
+       .remove   = gpiodrv_remove,
+#ifdef CONFIG_PM
+       .suspend  = gpiodrv_suspend,
+       .resume   = gpiodrv_resume,
+#endif
+};
+
+module_platform_driver(gpiodrv_gpio_driver);
+
+MODULE_DESCRIPTION("Mellanox BlueField GPIO Driver");
+MODULE_AUTHOR("Mellanox Technologies");
+MODULE_LICENSE("GPL");
-- 
2.1.2

Reply via email to