Adds support for USB-GPIO interface of Cypress Semiconductor CYUSBS234 USB-Serial Bridge controller. The GPIO get/set can be done through vendor command on control endpoint for the configured gpios. Details about the device can be found at: http://www.cypress.com/?rID=84126 Signed-off-by: Muthu Mani <muth@xxxxxxxxxxx> Signed-off-by: Rajaram Regupathy <rera@xxxxxxxxxxx> --- Changes since v2: * added helper macros * removed lock * given gpio chip device for dev_xxx * cleaned up the code Changes since v1: * allocated memory on heap for usb transfer data * changed gpio label as platform device name to identify multiple devices drivers/gpio/Kconfig | 13 ++++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-cyusbs23x.c | 174 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 188 insertions(+) create mode 100644 drivers/gpio/gpio-cyusbs23x.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 9de1515..932e07c 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -886,6 +886,19 @@ config GPIO_BCM_KONA comment "USB GPIO expanders:" +config GPIO_CYUSBS23X + tristate "CYUSBS23x GPIO support" + depends on MFD_CYUSBS23X && USB + help + Say yes here to access the GPIO signals of Cypress + Semiconductor CYUSBS23x USB Serial Bridge Controller. + + This driver enables the GPIO interface of CYUSBS23x USB Serial + Bridge controller. + + This driver can also be built as a module. If so, the module will be + called gpio-cyusbs23x. + config GPIO_VIPERBOARD tristate "Viperboard GPIO a & b support" depends on MFD_VIPERBOARD && USB diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 5d024e3..3ad89f1 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o obj-$(CONFIG_GPIO_CS5535) += gpio-cs5535.o obj-$(CONFIG_GPIO_CRYSTAL_COVE) += gpio-crystalcove.o +obj-$(CONFIG_GPIO_CYUSBS23X) += gpio-cyusbs23x.o obj-$(CONFIG_GPIO_DA9052) += gpio-da9052.o obj-$(CONFIG_GPIO_DA9055) += gpio-da9055.o obj-$(CONFIG_GPIO_DAVINCI) += gpio-davinci.o diff --git a/drivers/gpio/gpio-cyusbs23x.c b/drivers/gpio/gpio-cyusbs23x.c new file mode 100644 index 0000000..f2acbb8 --- /dev/null +++ b/drivers/gpio/gpio-cyusbs23x.c @@ -0,0 +1,174 @@ +/* + * GPIO subdriver for Cypress CYUSBS234 USB-Serial Bridge controller. + * Details about the device can be found at: + * http://www.cypress.com/?rID=84126 + * + * Copyright (c) 2014 Cypress Semiconductor Corporation. + * + * Author: + * Muthu Mani <muth@xxxxxxxxxxx> + * + * Additional contributors include: + * Rajaram Regupathy <rera@xxxxxxxxxxx> + * + * 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. + */ + +/* + * All GPIOs are exposed for get operation. Only the GPIOs which are configured + * by the user using the Configuration Utility can be set. Attempting to set + * value of unconfigured GPIOs would fail + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> + +#include <linux/usb.h> +#include <linux/gpio.h> + +#include <linux/mfd/cyusbs23x.h> + +#define CY_GPIO_GET_LEN 2 + +struct cyusbs_gpio { + struct gpio_chip gpio; + struct cyusbs23x *cyusbs; +}; + +#define to_cyusbs_gpio(chip) container_of(chip, struct cyusbs_gpio, gpio) + +static int cy_gpio_get(struct gpio_chip *chip, + unsigned offset) +{ + int ret; + char *buf; + u16 wIndex, wValue; + struct cyusbs_gpio *gpio = to_cyusbs_gpio(chip); + struct cyusbs23x *cyusbs = gpio->cyusbs; + + wValue = offset; + wIndex = 0; + buf = kmalloc(CY_GPIO_GET_LEN, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + + ret = usb_control_msg(cyusbs->usb_dev, + usb_rcvctrlpipe(cyusbs->usb_dev, 0), + CY_GPIO_GET_VALUE_CMD, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, + wValue, wIndex, buf, CY_GPIO_GET_LEN, + CY_USBS_CTRL_XFER_TIMEOUT); + if (ret == CY_GPIO_GET_LEN) { + dev_dbg(chip->dev, "%s: %02X %02X\n", __func__, buf[0], buf[1]); + if (buf[0] == 0) + ret = buf[1]; + else + ret = -EIO; + } else { + dev_err(chip->dev, "%s: %d\n", __func__, ret); + ret = -EIO; + } + + kfree(buf); + return ret; +} + +static void cy_gpio_set(struct gpio_chip *chip, + unsigned offset, int value) +{ + int ret; + u16 wIndex, wValue; + struct cyusbs_gpio *gpio = to_cyusbs_gpio(chip); + struct cyusbs23x *cyusbs = gpio->cyusbs; + + wValue = offset; + wIndex = value; + + ret = usb_control_msg(cyusbs->usb_dev, + usb_sndctrlpipe(cyusbs->usb_dev, 0), + CY_GPIO_SET_VALUE_CMD, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, + wValue, wIndex, NULL, 0, CY_USBS_CTRL_XFER_TIMEOUT); + if (ret < 0) + dev_err(chip->dev, "error setting gpio: %d\n", ret); +} + +static int cy_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + return 0; +} + +static int cy_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + return 0; +} + +static int cyusbs23x_gpio_probe(struct platform_device *pdev) +{ + struct cyusbs23x *cyusbs; + struct cyusbs_gpio *cy_gpio; + int ret = 0; + + dev_dbg(&pdev->dev, "%s\n", __func__); + + cyusbs = dev_get_drvdata(pdev->dev.parent); + + cy_gpio = devm_kzalloc(&pdev->dev, sizeof(*cy_gpio), GFP_KERNEL); + if (cy_gpio == NULL) + return -ENOMEM; + + cy_gpio->cyusbs = cyusbs; + /* registering gpio */ + cy_gpio->gpio.label = dev_name(&pdev->dev); + cy_gpio->gpio.dev = &pdev->dev; + cy_gpio->gpio.owner = THIS_MODULE; + cy_gpio->gpio.base = -1; + cy_gpio->gpio.ngpio = 12; /* total GPIOs */ + cy_gpio->gpio.can_sleep = true; + cy_gpio->gpio.set = cy_gpio_set; + cy_gpio->gpio.get = cy_gpio_get; + cy_gpio->gpio.direction_input = cy_gpio_direction_input; + cy_gpio->gpio.direction_output = cy_gpio_direction_output; + ret = gpiochip_add(&cy_gpio->gpio); + if (ret < 0) { + dev_err(cy_gpio->gpio.dev, "could not add gpio\n"); + return ret; + } + + platform_set_drvdata(pdev, cy_gpio); + + dev_dbg(&pdev->dev, "added GPIO\n"); + return ret; +} + +static int cyusbs23x_gpio_remove(struct platform_device *pdev) +{ + struct cyusbs_gpio *cy_gpio = platform_get_drvdata(pdev); + + dev_dbg(&pdev->dev, "%s\n", __func__); + gpiochip_remove(&cy_gpio->gpio); + return 0; +} + +static struct platform_driver cyusbs23x_gpio_driver = { + .driver.name = "cyusbs23x-gpio", + .probe = cyusbs23x_gpio_probe, + .remove = cyusbs23x_gpio_remove, +}; + +module_platform_driver(cyusbs23x_gpio_driver); + +MODULE_AUTHOR("Rajaram Regupathy <rera@xxxxxxxxxxx>"); +MODULE_AUTHOR("Muthu Mani <muth@xxxxxxxxxxx>"); +MODULE_DESCRIPTION("GPIO driver for CYUSBS23x"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:cyusbs23x-gpio"); -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
