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 v3: * added reading gpio configuration from device * exposed only the gpios available * exposed correct direction of gpios * removed the direction input/output handler as setting gpio direction is not supported by the device 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 | 284 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 298 insertions(+) create mode 100644 drivers/gpio/gpio-cyusbs23x.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 0959ca9..66f460f5 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -894,6 +894,19 @@ 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 e5d346c..da30751 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..9f6beb1 --- /dev/null +++ b/drivers/gpio/gpio-cyusbs23x.c @@ -0,0 +1,284 @@ +/* + * 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 +#define CY_DEVICE_CONFIG_SIZE 512 + +/* total GPIOs present */ +#define CYUSBS234_GPIO_NUM 12 + +struct cyusbs_gpio { + struct gpio_chip gpio; + struct cyusbs23x *cyusbs; + u32 out_gpio; + u32 out_value; + u32 in_gpio; +}; + +#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; + + if (gpio->out_gpio & (1 << offset)) + return gpio->out_value & (1 << offset); + + 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: offset=%d %02X %02X\n", + __func__, offset, buf[0], buf[1]); + if (buf[0] == 0) + ret = buf[1]; + else + ret = -EIO; + } else { + dev_err(chip->dev, "%s: offset=%d %d\n", __func__, offset, 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: %d\n", offset, ret); + else { + if (value) + gpio->out_value |= (1 << offset); + else + gpio->out_value &= ~(1 << offset); + } +} + +static int cy_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + u32 gpios; + struct cyusbs_gpio *gpio = to_cyusbs_gpio(chip); + + gpios = gpio->out_gpio | gpio->in_gpio; + if (gpios & (1 << offset)) + return 0; + + return -ENODEV; +} + +static int cy_gpio_get_direction(struct gpio_chip *chip, + unsigned offset) +{ + struct cyusbs_gpio *gpio = to_cyusbs_gpio(chip); + + if (gpio->out_gpio & (1 << offset)) + return GPIOF_DIR_OUT; + else if (gpio->in_gpio & (1 << offset)) + return GPIOF_DIR_IN; + + return -EIO; +} + +static int cy_get_device_config(struct cyusbs23x *cyusbs, u8 *buf) +{ + int ret; + + ret = usb_control_msg(cyusbs->usb_dev, + usb_sndctrlpipe(cyusbs->usb_dev, 0), + CY_DEV_ENABLE_CONFIG_READ_CMD, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT, + 0xA6BC, 0xB1B0, NULL, 0, + CY_USBS_CTRL_XFER_TIMEOUT); + if (ret) { + dev_err(&cyusbs->usb_dev->dev, + "%s: enable config read status%d\n", __func__, ret); + return -ENODEV; + } + + ret = usb_control_msg(cyusbs->usb_dev, + usb_rcvctrlpipe(cyusbs->usb_dev, 0), + CY_DEV_CMD_READ_CONFIG, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, + 0, 0, buf, CY_DEVICE_CONFIG_SIZE, + CY_USBS_CTRL_XFER_TIMEOUT); + if (ret != CY_DEVICE_CONFIG_SIZE) { + dev_err(&cyusbs->usb_dev->dev, + "%s: read config status %d\n", __func__, ret); + return -ENODEV; + } + + ret = usb_control_msg(cyusbs->usb_dev, + usb_sndctrlpipe(cyusbs->usb_dev, 0), + CY_DEV_ENABLE_CONFIG_READ_CMD, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT, + 0xA6BC, 0xB9B0, NULL, 0, + CY_USBS_CTRL_XFER_TIMEOUT); + if (ret) { + dev_err(&cyusbs->usb_dev->dev, + "%s: disable config read status%d\n", __func__, ret); + return -ENODEV; + } + + return 0; +} + +static int cy_gpio_retrieve_gpio_details(struct cyusbs_gpio *gpio) +{ + int ret; + u32 drive0, drive1; + u8 *buf; + struct cyusbs23x *cyusbs = gpio->cyusbs; + + buf = kzalloc(CY_DEVICE_CONFIG_SIZE, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + + ret = cy_get_device_config(cyusbs, buf); + if (ret) { + dev_err(&cyusbs->usb_dev->dev, + "could not retrieve device configuration\n"); + goto error; + } + + /* Retrieve the GPIO configuration details */ + drive0 = *((u32 *)&buf[436]); + drive1 = *((u32 *)&buf[440]); + gpio->out_gpio = drive0 | drive1; + gpio->out_value = drive1; + gpio->in_gpio = *((u32 *)&buf[444]); + +error: + kfree(buf); + return ret; +} + +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; + /* retrieve GPIO configuration info */ + ret = cy_gpio_retrieve_gpio_details(cy_gpio); + if (ret) { + dev_err(&pdev->dev, "could not retrieve gpio details\n"); + return -ENODEV; + } + + /* 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 = CYUSBS234_GPIO_NUM; + cy_gpio->gpio.can_sleep = true; + cy_gpio->gpio.request = cy_gpio_request; + cy_gpio->gpio.set = cy_gpio_set; + cy_gpio->gpio.get = cy_gpio_get; + cy_gpio->gpio.get_direction = cy_gpio_get_direction; + 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 This message and any attachments may contain Cypress (or its subsidiaries) confidential information. 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