[PATCH v2 12/18] gpio: madera: Support Cirrus Logic Madera class codecs

From: Richard Fitzgerald
Date: Mon Apr 24 2017 - 12:10:21 EST


This adds support for the GPIOs on Cirrus Logic Madera class codecs.
Any pins not used for special functions (see the pinctrl driver) can be
used as general single-bit input or output lines. The number of available
GPIOs varies between codecs.

Signed-off-by: Nariman Poushin <nariman@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---
Changes from V1:
- dt bindings moved to a separate patch
- dependent on pinctrl driver instead of parent MFD
- added get_direction function
- added .request / .free / .set_config to work with pinctrl driver
- register range with pinctrl driver

MAINTAINERS | 2 +
drivers/gpio/Kconfig | 6 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-madera.c | 196 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 205 insertions(+)
create mode 100644 drivers/gpio/gpio-madera.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 3e42a03..66c5263 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3304,10 +3304,12 @@ L: patches@xxxxxxxxxxxxxxxxxxxxxxxxxxx
T: git https://github.com/CirrusLogic/linux-drivers.git
W: https://github.com/CirrusLogic/linux-drivers/wiki
S: Supported
+F: Documentation/devicetree/bindings/gpio/gpio-madera.txt
F: Documentation/devicetree/bindings/mfd/madera.txt
F: Documentation/devicetree/bindings/pinctrl/cirrus,madera-pinctrl.txt
F: include/linux/irqchip/irq-madera*
F: include/linux/mfd/madera/*
+F: drivers/gpio/gpio-madera*
F: drivers/irqchip/irq-madera*
F: drivers/mfd/madera*
F: drivers/mfd/cs47l*
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 05e8fbf..9488abe 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -941,6 +941,12 @@ config GPIO_LP873X
This driver can also be built as a module. If so, the module will be
called gpio-lp873x.

+config GPIO_MADERA
+ bool "Cirrus Logic Madera class codecs"
+ depends on PINCTRL_MADERA
+ help
+ Support for GPIOs on Cirrus Logic Madera class codecs.
+
config GPIO_MAX77620
tristate "GPIO support for PMIC MAX77620 and MAX20024"
depends on MFD_MAX77620
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 095598e..d4b6c30 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -66,6 +66,7 @@ obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o
obj-$(CONFIG_ARCH_LPC32XX) += gpio-lpc32xx.o
obj-$(CONFIG_GPIO_LP873X) += gpio-lp873x.o
obj-$(CONFIG_GPIO_LYNXPOINT) += gpio-lynxpoint.o
+obj-$(CONFIG_GPIO_MADERA) += gpio-madera.o
obj-$(CONFIG_GPIO_MAX730X) += gpio-max730x.o
obj-$(CONFIG_GPIO_MAX7300) += gpio-max7300.o
obj-$(CONFIG_GPIO_MAX7301) += gpio-max7301.o
diff --git a/drivers/gpio/gpio-madera.c b/drivers/gpio/gpio-madera.c
new file mode 100644
index 0000000..37ac706
--- /dev/null
+++ b/drivers/gpio/gpio-madera.c
@@ -0,0 +1,196 @@
+/*
+ * GPIO support for Cirrus Logic Madera codecs
+ *
+ * Copyright 2015-2017 Cirrus Logic
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/madera/core.h>
+#include <linux/mfd/madera/pdata.h>
+#include <linux/mfd/madera/registers.h>
+
+struct madera_gpio {
+ struct madera *madera;
+ struct gpio_chip gpio_chip;
+};
+
+static int madera_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+ struct madera *madera = madera_gpio->madera;
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(madera->regmap,
+ MADERA_GPIO1_CTRL_2 + (2 * offset), &val);
+ if (ret < 0)
+ return ret;
+
+ return (val & MADERA_GP1_DIR_MASK) >> MADERA_GP1_DIR_SHIFT;
+}
+
+static int madera_gpio_direction_in(struct gpio_chip *chip, unsigned int offset)
+{
+ struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+ struct madera *madera = madera_gpio->madera;
+
+ return regmap_update_bits(madera->regmap,
+ MADERA_GPIO1_CTRL_2 + (2 * offset),
+ MADERA_GP1_DIR_MASK, MADERA_GP1_DIR);
+}
+
+static int madera_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+ struct madera *madera = madera_gpio->madera;
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(madera->regmap,
+ MADERA_GPIO1_CTRL_1 + (2 * offset), &val);
+ if (ret < 0)
+ return ret;
+
+ return !!(val & MADERA_GP1_LVL_MASK);
+}
+
+static int madera_gpio_direction_out(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+ struct madera *madera = madera_gpio->madera;
+ unsigned int regval;
+ int ret;
+
+ if (value)
+ regval = MADERA_GP1_LVL;
+ else
+ regval = 0;
+
+ ret = regmap_update_bits(madera->regmap,
+ MADERA_GPIO1_CTRL_2 + (2 * offset),
+ MADERA_GP1_DIR_MASK, 0);
+ if (ret < 0)
+ return ret;
+
+ return regmap_update_bits(madera->regmap,
+ MADERA_GPIO1_CTRL_1 + (2 * offset),
+ MADERA_GP1_LVL_MASK, regval);
+}
+
+static void madera_gpio_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+ struct madera *madera = madera_gpio->madera;
+ unsigned int regval;
+ int ret;
+
+ if (value)
+ regval = MADERA_GP1_LVL;
+ else
+ regval = 0;
+
+ ret = regmap_update_bits(madera->regmap,
+ MADERA_GPIO1_CTRL_1 + (2 * offset),
+ MADERA_GP1_LVL_MASK, regval);
+ if (ret)
+ dev_warn(madera->dev, "Failed to write to 0x%x (%d)\n",
+ MADERA_GPIO1_CTRL_1 + (2 * offset), ret);
+}
+
+static struct gpio_chip template_chip = {
+ .label = "madera",
+ .owner = THIS_MODULE,
+ .request = gpiochip_generic_request,
+ .free = gpiochip_generic_free,
+ .get_direction = madera_gpio_get_direction,
+ .direction_input = madera_gpio_direction_in,
+ .get = madera_gpio_get,
+ .direction_output = madera_gpio_direction_out,
+ .set = madera_gpio_set,
+ .set_config = gpiochip_generic_config,
+ .can_sleep = true,
+};
+
+static int madera_gpio_probe(struct platform_device *pdev)
+{
+ struct madera *madera = dev_get_drvdata(pdev->dev.parent);
+ struct madera_pdata *pdata = dev_get_platdata(madera->dev);
+ struct madera_gpio *madera_gpio;
+ int ret;
+
+ madera_gpio = devm_kzalloc(&pdev->dev, sizeof(*madera_gpio),
+ GFP_KERNEL);
+ if (!madera_gpio)
+ return -ENOMEM;
+
+ madera_gpio->madera = madera;
+ madera_gpio->gpio_chip = template_chip;
+ madera_gpio->gpio_chip.parent = &pdev->dev;
+
+ if (IS_ENABLED(CONFIG_OF_GPIO))
+ madera_gpio->gpio_chip.of_node = pdev->dev.of_node;
+
+ switch (madera->type) {
+ case CS47L35:
+ madera_gpio->gpio_chip.ngpio = CS47L35_NUM_GPIOS;
+ break;
+ case CS47L85:
+ case WM1840:
+ madera_gpio->gpio_chip.ngpio = CS47L85_NUM_GPIOS;
+ break;
+ case CS47L90:
+ case CS47L91:
+ madera_gpio->gpio_chip.ngpio = CS47L90_NUM_GPIOS;
+ break;
+ default:
+ dev_err(&pdev->dev, "Unknown chip variant %d\n", madera->type);
+ return -EINVAL;
+ }
+
+ if (pdata && pdata->gpio_base)
+ madera_gpio->gpio_chip.base = pdata->gpio_base;
+ else
+ madera_gpio->gpio_chip.base = -1;
+
+ ret = devm_gpiochip_add_data(&pdev->dev, &madera_gpio->gpio_chip,
+ madera_gpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
+ return ret;
+ }
+
+ ret = gpiochip_add_pin_range(&madera_gpio->gpio_chip, "madera-pinctrl",
+ 0, 0, madera_gpio->gpio_chip.ngpio);
+ if (ret) {
+ dev_warn(&pdev->dev, "Failed to add pin range (%d)\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver madera_gpio_driver = {
+ .driver.name = "madera-gpio",
+ .driver.owner = THIS_MODULE,
+ .probe = madera_gpio_probe,
+};
+
+module_platform_driver(madera_gpio_driver);
+
+MODULE_DESCRIPTION("GPIO interface for Madera codecs");
+MODULE_AUTHOR("Nariman Poushin <nariman@xxxxxxxxxxxxxxxxxxxxxxxxxxx>");
+MODULE_AUTHOR("Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:madera-gpio");
--
1.9.1