[PATCH v4 0/5] ARM: Add GPIO support

From: nick . hawkins
Date: Wed Jun 21 2023 - 17:36:00 EST


From: Nick Hawkins <nick.hawkins@xxxxxxx>

The GXP SoC supports GPIO on multiple interfaces. The interfaces are
CPLD and Host. The GPIOs is a combination of both physical and virtual
I/O across the interfaces. The gpio-gxp driver specifically covers the
CSM(physical), FN2(virtual), and VUHC(virtual) which are the host. The
gpio-gxp-pl driver covers the CPLD which takes physical I/O from the
board and shares it with GXP via a propriety interface that maps the I/O
onto a specific register area of the GXP. The drivers both support
interrupts but from different interrupt parents.

After exploring the recommendation of using regmap_gpio it does not seem
like a good fit. Some of the GPIOs are a combination of several bits in
a byte where others are not contiguous blocks of GPIOs.

The gxp-fan-ctrl driver in HWMON no longer will report fan presence
or fan failure states as these GPIOs providing this information will be
consumed by the host. It will be the hosts function to keep track of
fan presence and status.

---

Changes since v3:
*Added called with debugfs to read server id
*Added reviewed-by: tags to hwmon fan driver and fan yaml
*Changed maxItems to be 4 instead of 6 on reg and reg-names in gpio
yaml
*Moved gpio-gxp-pl.c to be in a separate patch/commit.
*Moved regmap_config out of function in both gpio drivers to turn into
static const
*Removed unnecesary variables and redundant conditionals
*Modified regmap_read switch statements to calculate offset and mask
then read at end
*Removed use of -EOPNOTSUPP in favor of -ENOTSUPP
*Removed redundant casting
*Switched generic_handle_irq for generic_handle_domain_irq
*Used GENMASK where applicable
*Used bitmap_xor and for_each_bit_set in PL PSU interrupt
*Made GPIO chip const and marked as a template (in the name)
*Made irq_chip const and immutable
*Corrected check on devm_gpiochip_add_data
*Removed dev_err_probe on platform_get_irq
*Changed return 0 to devm_request_irq

Changes since v2:
*Removed shared fan variables between HWMON and GPIO based on feedback
*Removed reporting fan presence and failure from hwmon gxp-fan-ctrl
driver
*Removed GPIO dependency from gxp-fan-ctrl driver
*Changed description and title for hpe,gxp-gpio binding
*Corrected indention on example for hpe,gxp-gpio binding
*Removed additional example from hpe,gxp-gpio binding

Changes since v1:
*Removed ARM device tree changes and defconfig changes to reduce
patchset size
*Removed GXP PSU changes to reduce patchset size
*Corrected hpe,gxp-gpio YAML file based on feedback
*Created new gpio-gxp-pl file to reduce complexity
*Separated code into two files to keep size down: gpio-gxp.c and
gpio-gxp-pl.c
*Fixed Kconfig indentation as well as add new entry for gpio-gxp-pl
*Removed use of linux/of.h and linux/of_device.h
*Added mod_devicetable.h and property.h
*Fixed indentation of defines and uses consistent number of digits
*Corrected defines with improper GPIO_ namespace.
*For masks now use BIT()
*Added comment for PLREG offsets
*Move gpio_chip to be first in structure
*Calculate offset for high and low byte GPIO reads instead of having
H(High) and L(Low) letters added to the variables.
*Removed repeditive use of "? 1 : 0"
*Switched to handle_bad_irq()
*Removed improper bailout on gpiochip_add_data
*Used GENMASK to arm interrupts
*Removed use of of_match_device
*fixed sizeof in devm_kzalloc
*Added COMPILE_TEST to Kconfig
*Added dev_err_probe where applicable
*Removed unecessary parent and compatible checks

Nick Hawkins (5):
gpio: gxp: Add HPE GXP GPIO
gpio: gxp: Add HPE GXP GPIO PL
dt-bindings: hwmon: hpe,gxp-fan-ctrl: remove fn2 and pl registers
hwmon: (gxp_fan_ctrl) Provide fan info via gpio
MAINTAINERS: hpe: Add GPIO

.../bindings/hwmon/hpe,gxp-fan-ctrl.yaml | 16 +-
MAINTAINERS | 2 +
drivers/gpio/Kconfig | 18 +
drivers/gpio/Makefile | 2 +
drivers/gpio/gpio-gxp-pl.c | 582 ++++++++++++++++++
drivers/gpio/gpio-gxp.c | 573 +++++++++++++++++
drivers/hwmon/Kconfig | 2 +-
drivers/hwmon/gxp-fan-ctrl.c | 108 +---
8 files changed, 1184 insertions(+), 119 deletions(-)
create mode 100644 drivers/gpio/gpio-gxp-pl.c
create mode 100644 drivers/gpio/gpio-gxp.c

--
2.17.1