From: Mauri Sandberg <sandberg@mailfence.com>
To: sandberg@mailfence.com
Cc: andy.shevchenko@gmail.com, bgolaszewski@baylibre.com,
geert+renesas@glider.be, linus.walleij@linaro.org,
linux-gpio@vger.kernel.org, drew@beagleboard.org,
kernel test robot <lkp@intel.com>
Subject: [RFC v2 2/2] gpio: gpio-mux-input: add generic gpio input multiplexer
Date: Mon, 29 Mar 2021 16:57:29 +0300 [thread overview]
Message-ID: <20210329135729.10523-3-sandberg@mailfence.com> (raw)
In-Reply-To: <20210329135729.10523-1-sandberg@mailfence.com>
Adds support for a generic GPIO multiplexer. To drive the multiplexer a
mux-controller is needed. The output pin of the multiplexer is a GPIO
pin.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Mauri Sandberg <sandberg@mailfence.com>
---
drivers/gpio/Kconfig | 13 ++++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-mux-input.c | 134 ++++++++++++++++++++++++++++++++++
3 files changed, 148 insertions(+)
create mode 100644 drivers/gpio/gpio-mux-input.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b6b6150d0d04..7bf8021e0239 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1643,4 +1643,17 @@ config GPIO_SIM
endmenu
+comment "Other GPIO expanders"
+
+config GPIO_MUX_INPUT
+ tristate "General GPIO input multiplexer"
+ depends on OF_GPIO
+ select MULTIPLEXER
+ select MUX_GPIO
+ help
+ Say yes here to enable support for generic GPIO input multiplexer.
+
+ This driver uses a mux-controller to drive the multiplexer and has a
+ single output pin for reading the inputs to the mux.
+
endif
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d717aa85f8e1..e843e1bcfc20 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -103,6 +103,7 @@ obj-$(CONFIG_GPIO_MPC5200) += gpio-mpc5200.o
obj-$(CONFIG_GPIO_MPC8XXX) += gpio-mpc8xxx.o
obj-$(CONFIG_GPIO_MSC313) += gpio-msc313.o
obj-$(CONFIG_GPIO_MT7621) += gpio-mt7621.o
+obj-$(CONFIG_GPIO_MUX_INPUT) += gpio-mux-input.o
obj-$(CONFIG_GPIO_MVEBU) += gpio-mvebu.o
obj-$(CONFIG_GPIO_MXC) += gpio-mxc.o
obj-$(CONFIG_GPIO_MXS) += gpio-mxs.o
diff --git a/drivers/gpio/gpio-mux-input.c b/drivers/gpio/gpio-mux-input.c
new file mode 100644
index 000000000000..2de198a84bb9
--- /dev/null
+++ b/drivers/gpio/gpio-mux-input.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * A generic GPIO input multiplexer driver
+ *
+ * Copyright (C) 2021 Mauri Sandberg <sandberg@mailfence.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/mux/consumer.h>
+
+struct gpio_mux_input {
+ struct device *parent;
+ struct gpio_chip gpio_chip;
+ struct mux_control *mux_control;
+ struct gpio_desc *mux_pin;
+};
+
+static struct gpio_mux_input *gpio_to_mux(struct gpio_chip *gc)
+{
+ return container_of(gc, struct gpio_mux_input, gpio_chip);
+}
+
+static int gpio_mux_input_get_direction(struct gpio_chip *gc,
+ unsigned int offset)
+{
+ return GPIO_LINE_DIRECTION_IN;
+}
+
+static int gpio_mux_input_get_value(struct gpio_chip *gc, unsigned int offset)
+{
+ struct gpio_mux_input *mux;
+ int ret;
+
+ mux = gpio_to_mux(gc);
+ ret = mux_control_select(mux->mux_control, offset);
+ if (ret)
+ return ret;
+
+ ret = gpiod_get_value(mux->mux_pin);
+ mux_control_deselect(mux->mux_control);
+ return ret;
+}
+
+static int gpio_mux_input_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct gpio_mux_input *mux;
+ struct gpio_chip *gc;
+ struct mux_control *mc;
+ struct gpio_desc *pin;
+ int err;
+
+ mux = kzalloc(sizeof(struct gpio_mux_input), GFP_KERNEL);
+ if (mux == NULL)
+ return -ENOMEM;
+
+ mc = mux_control_get(&pdev->dev, NULL);
+ if (IS_ERR(mc)) {
+ err = (int) PTR_ERR(mc);
+ if (err != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "unable to get mux-control: %d\n",
+ err);
+ goto err_free_mux;
+ }
+
+ mux->mux_control = mc;
+ pin = gpiod_get(&pdev->dev, "pin", GPIOD_IN);
+ if (IS_ERR(pin)) {
+ err = (int) PTR_ERR(pin);
+ dev_err(&pdev->dev, "unable to claim pin GPIO: %d\n", err);
+ goto err_free_mc;
+ }
+
+ mux->mux_pin = pin;
+ mux->parent = &pdev->dev;
+
+ gc = &mux->gpio_chip;
+ gc->get = gpio_mux_input_get_value;
+ gc->get_direction = gpio_mux_input_get_direction;
+
+ gc->base = -1;
+ gc->ngpio = mux_control_states(mc);
+ gc->label = dev_name(mux->parent);
+ gc->parent = mux->parent;
+ gc->owner = THIS_MODULE;
+ gc->of_node = np;
+
+ err = gpiochip_add(&mux->gpio_chip);
+ if (err) {
+ dev_err(&pdev->dev, "unable to add gpio chip, err=%d\n", err);
+ goto err_free_pin;
+ }
+
+ platform_set_drvdata(pdev, mux);
+
+ dev_info(&pdev->dev, "registered %u input GPIOs\n", gc->ngpio);
+
+ return 0;
+
+err_free_pin:
+ gpiod_put(pin);
+err_free_mc:
+ mux_control_put(mc);
+err_free_mux:
+ kfree(mux);
+ return err;
+}
+
+static const struct of_device_id gpio_mux_input_id[] = {
+ {
+ .compatible = "gpio-mux-input",
+ .data = NULL,
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, gpio_mux_input_id);
+
+static struct platform_driver gpio_mux_input_driver = {
+ .driver = {
+ .name = "gpio-mux-input",
+ .of_match_table = gpio_mux_input_id,
+ },
+ .probe = gpio_mux_input_probe,
+};
+module_platform_driver(gpio_mux_input_driver);
+
+MODULE_AUTHOR("Mauri Sandberg <sandberg@mailfence.com>");
+MODULE_DESCRIPTION("Generic GPIO input multiplexer");
+MODULE_LICENSE("GPL");
--
2.25.1
next prev parent reply other threads:[~2021-03-29 14:01 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-25 12:28 [RFC gpio/for-next 0/2] gpio: add generic gpio input multiplexer Mauri Sandberg
2021-03-25 12:28 ` [RFC gpio/for-next 1/2] dt-bindings: gpio-mux-input: add documentation Mauri Sandberg
2021-03-25 12:28 ` [RFC gpio/for-next 2/2] gpio: gpio-mux-input: add generic gpio input multiplexer Mauri Sandberg
2021-03-26 6:59 ` Drew Fustini
2021-03-26 10:32 ` Mauri Sandberg
2021-03-26 10:49 ` Andy Shevchenko
2021-03-29 13:57 ` [RFC v2 0/2] gpio: " Mauri Sandberg
2021-03-29 13:57 ` [RFC v2 1/2] dt-bindings: gpio-mux-input: add documentation Mauri Sandberg
2021-03-29 13:57 ` Mauri Sandberg [this message]
2021-05-17 16:58 ` [PATCH v3 0/2] gpio: add generic gpio input multiplexer Mauri Sandberg
2021-05-17 16:58 ` [PATCH v3 1/2] dt-bindings: gpio-mux-input: add documentation Mauri Sandberg
2021-05-17 16:58 ` [PATCH v3 2/2] gpio: gpio-mux-input: add generic gpio input multiplexer Mauri Sandberg
2021-05-17 22:13 ` [PATCH v3 0/2] gpio: " Drew Fustini
2021-05-28 0:23 ` Linus Walleij
2021-05-28 0:27 ` Drew Fustini
2021-05-24 21:25 ` Drew Fustini
2021-05-24 16:29 ` RESEND PATCH v3 Mauri Sandberg
2021-05-24 16:29 ` [PATCH v3 1/2] dt-bindings: gpio-mux-input: add documentation Mauri Sandberg
2021-05-24 16:29 ` [PATCH v3 2/2] gpio: gpio-mux-input: add generic gpio input multiplexer Mauri Sandberg
2021-05-24 21:29 ` RESEND PATCH v3 Drew Fustini
2021-05-30 16:13 ` [PATCH v4 0/2] gpio: add generic gpio input multiplexer Mauri Sandberg
2021-05-30 16:13 ` [PATCH v4 1/2] dt-bindings: gpio-mux-input: add documentation Mauri Sandberg
2021-06-01 10:10 ` Linus Walleij
2021-06-01 10:44 ` Linus Walleij
2021-06-02 9:31 ` Mauri Sandberg
2021-06-02 10:35 ` Linus Walleij
2021-06-02 11:21 ` Mauri Sandberg
2021-06-04 7:51 ` Linus Walleij
2021-06-01 13:32 ` Rob Herring
2021-06-02 11:36 ` Mauri Sandberg
2021-05-30 16:13 ` [PATCH v4 2/2] gpio: gpio-mux-input: add generic gpio input multiplexer Mauri Sandberg
2021-05-30 18:09 ` Andy Shevchenko
2021-05-30 19:02 ` Mauri Sandberg
2021-05-30 19:38 ` Andy Shevchenko
2021-05-31 10:19 ` Mauri Sandberg
2021-06-01 10:38 ` Linus Walleij
2021-06-21 17:20 ` [PATCH v5 0/2] gpio: add generic gpio cascade Mauri Sandberg
2021-06-21 17:20 ` [PATCH v5 1/2] dt-bindings: gpio-cascade: add documentation Mauri Sandberg
2021-06-24 18:30 ` Rob Herring
2021-06-21 17:20 ` [PATCH v5 2/2] gpio: gpio-cascade: add generic GPIO cascade Mauri Sandberg
2021-06-21 17:43 ` Andy Shevchenko
2021-06-21 18:31 ` Enrico Weigelt, metux IT consult
2021-10-15 12:56 ` Mauri Sandberg
2021-10-15 17:20 ` Andy Shevchenko
2021-10-19 12:57 ` [PATCH v6 0/2] " Mauri Sandberg
2021-10-19 12:57 ` [PATCH v6 1/2] dt-bindings: gpio-cascade: add documentation Mauri Sandberg
2021-10-19 12:57 ` [PATCH v6 2/2] gpio: gpio-cascade: add generic GPIO cascade Mauri Sandberg
2021-10-19 13:12 ` Andy Shevchenko
2021-10-19 20:08 ` [PATCH v7 0/2] " Mauri Sandberg
2021-10-19 20:08 ` [PATCH v7 1/2] dt-bindings: gpio-cascade: add documentation Mauri Sandberg
2021-10-24 22:18 ` Linus Walleij
2021-10-19 20:08 ` [PATCH v7 2/2] gpio: gpio-cascade: add generic GPIO cascade Mauri Sandberg
2021-10-24 22:17 ` Linus Walleij
2021-10-25 9:29 ` Andy Shevchenko
2021-10-26 19:15 ` [PATCH v8 0/2] " Mauri Sandberg
2021-10-26 19:15 ` [PATCH v8 1/2] dt-bindings: gpio-cascade: add documentation Mauri Sandberg
2021-10-26 19:15 ` [PATCH v8 2/2] gpio: gpio-cascade: add generic GPIO cascade Mauri Sandberg
2022-02-05 21:59 ` [RESEND v8 0/2] " Mauri Sandberg
2022-02-05 21:59 ` [RESEND v8 1/2] dt-bindings: gpio-cascade: add documentation Mauri Sandberg
2022-02-05 21:59 ` [RESEND v8 2/2] gpio: gpio-cascade: add generic GPIO cascade Mauri Sandberg
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210329135729.10523-3-sandberg@mailfence.com \
--to=sandberg@mailfence.com \
--cc=andy.shevchenko@gmail.com \
--cc=bgolaszewski@baylibre.com \
--cc=drew@beagleboard.org \
--cc=geert+renesas@glider.be \
--cc=linus.walleij@linaro.org \
--cc=linux-gpio@vger.kernel.org \
--cc=lkp@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).