Hi Bart, > -----Original Message----- > From: Bartosz Golaszewski <brgl@xxxxxxxx> > Sent: Monday, January 22, 2024 9:00 PM > To: Paller, Kim Seer <KimSeer.Paller@xxxxxxxxxx> > Cc: linux-gpio@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Linus Walleij <linus.walleij@xxxxxxxxxx>; Rob Herring > <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski > <krzysztof.kozlowski+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx> > Subject: Re: [PATCH 2/2] gpio: gpio-adg1414: New driver > > [External] > > On Sun, Jan 21, 2024 at 11:35 AM Kim Seer Paller > <kimseer.paller@xxxxxxxxxx> wrote: > > > > The ADG1414 is a 9.5 Ω RON ±15 V/+12 V/±5 V iCMOS Serially-Controlled > > Octal SPST Switches > > Switch? (singular) It's most likely to be in plural since the device has 8 individual SPST switches, as also stated in the datasheet. > > > > Signed-off-by: Kim Seer Paller <kimseer.paller@xxxxxxxxxx> > > --- > > MAINTAINERS | 1 + > > drivers/gpio/Kconfig | 10 +++ > > drivers/gpio/Makefile | 1 + > > drivers/gpio/gpio-adg1414.c | 141 > ++++++++++++++++++++++++++++++++++++ > > 4 files changed, 153 insertions(+) > > create mode 100644 drivers/gpio/gpio-adg1414.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index 526145e69..254ba7ea5 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -466,6 +466,7 @@ M: Kim Seer Paller <kimseer.paller@xxxxxxxxxx> > > S: Supported > > W: https://ez.analog.com/linux-software-drivers > > F: Documentation/devicetree/bindings/gpio/gpio-adg1414.yaml > > +F: drivers/gpio/gpio-adg1414.c > > > > ADM1025 HARDWARE MONITOR DRIVER > > M: Jean Delvare <jdelvare@xxxxxxxx> > > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig > > index 1301cec94..25d467d70 100644 > > --- a/drivers/gpio/Kconfig > > +++ b/drivers/gpio/Kconfig > > @@ -1728,6 +1728,16 @@ config GPIO_74X164 > > shift registers. This driver can be used to provide access > > to more GPIO outputs. > > > > +config GPIO_ADG1414 > > + tristate "ADG1414 SPST Switch Driver" > > + depends on SPI > > + help > > + Say yes here to build support for Analog Devices ADG1414 SPST > > + Switch Driver > > + > > + To compile this driver as a module, choose M here: the > > + module will be called gpio-adg1414. > > + > > config GPIO_MAX3191X > > tristate "Maxim MAX3191x industrial serializer" > > select CRC8 > > diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile > > index 9e40af196..9ab45d128 100644 > > --- a/drivers/gpio/Makefile > > +++ b/drivers/gpio/Makefile > > @@ -24,6 +24,7 @@ obj-$(CONFIG_GPIO_104_IDI_48) += gpio-104-idi- > 48.o > > obj-$(CONFIG_GPIO_104_IDIO_16) += gpio-104-idio-16.o > > obj-$(CONFIG_GPIO_74X164) += gpio-74x164.o > > obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o > > +obj-$(CONFIG_GPIO_ADG1414) += gpio-adg1414.o > > obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o > > obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o > > obj-$(CONFIG_GPIO_AGGREGATOR) += gpio-aggregator.o > > diff --git a/drivers/gpio/gpio-adg1414.c b/drivers/gpio/gpio-adg1414.c > > new file mode 100644 > > index 000000000..6c0830ee2 > > --- /dev/null > > +++ b/drivers/gpio/gpio-adg1414.c > > @@ -0,0 +1,141 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * ADG1414 SPST Switch Driver > > + * > > + * Copyright 2024 Analog Devices Inc. > > + */ > > + > > +#include <linux/delay.h> > > +#include <linux/gpio/consumer.h> > > +#include <linux/gpio/driver.h> > > +#include <linux/spi/spi.h> > > +#include <linux/module.h> > > Can you keep the headers in alphabetical order please? > > > +#include <linux/property.h> > > + > > +#define ADG1414_MAX_DEVICES 4 > > + > > +struct adg1414_state { > > + struct spi_device *spi; > > + struct gpio_chip chip; > > + struct mutex lock; /* protect sensor state */ > > Locking here is simple enough that you could use the SPI regmap and > get it to do the serialization for you. And then you could possibly > reuse the gpio-regmap abstraction and get an even smaller footprint. I could not seem to figure out how to use the SPI regmap in this case. Since the number of daisy-chained devices depends on the length of data transferred with continuous transaction, I could not determine how to implement that using the SPI regmap. Or maybe I misunderstood the statement. However, is it still acceptable to use the current approach? Best regards, Kim
