gpio: add driver for Mellanox BlueField GPIO controller

Changes since v3
- the naming scheme has been fixed to remove double underscores and use
standard variable names
- the locking has been updated to protect the entire read/modify
operations.

Regarding the suggested use of the generic MMIO library, I noticed that bgpio_init only allows for either dirin or dirout to be set, never both. But since our controller has 2 separate registers, using bgpio_init might not be possible here.

Shravan Kumar Ramani (1):
gpio: add driver for Mellanox BlueField GPIO controller

 drivers/gpio/Kconfig      |   6 ++
 drivers/gpio/Makefile     |   1 +
 drivers/gpio/gpio-mlxbf.c | 222 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 229 insertions(+)
 create mode 100644 drivers/gpio/gpio-mlxbf.c

2.1.2

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

---
 drivers/gpio/Kconfig      |   6 ++
 drivers/gpio/Makefile     |   1 +
 drivers/gpio/gpio-mlxbf.c | 222 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 229 insertions(+)
 create mode 100644 drivers/gpio/gpio-mlxbf.c

index b5a2845..c950fe8 100644
@@ -1292,6 +1292,12 @@ 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
+	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

index 37628f8..8d54279 100644
@@ -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

2.1.2

OK let's just fix that instead of working around it, I will send a patch.

Yours,
Linus Walleij