From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cyril Chemparathy Subject: [PATCH v7 08/12] gpio: add ti-ssp gpio driver Date: Tue, 7 Dec 2010 09:51:58 -0500 Message-ID: <1291733522-3626-9-git-send-email-cyril@ti.com> References: <1291733522-3626-1-git-send-email-cyril@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, khilman-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org, Cyril Chemparathy , akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, alan-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org To: davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org, spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, sameo-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, lrg-kDsPt+C1G03kYMGBc/C6ZA@public.gmane.org, broonie-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org, rpurdie@rpsys Return-path: In-Reply-To: <1291733522-3626-1-git-send-email-cyril-l0cyMroinI0@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org TI's SSP controller pins can be directly read and written to behave like a GPIO. This patch adds a GPIO driver that exposes such functionality. Signed-off-by: Cyril Chemparathy --- drivers/gpio/Kconfig | 10 ++ drivers/gpio/Makefile | 1 + drivers/gpio/ti-ssp-gpio.c | 206 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/mfd/ti_ssp.h | 4 + 4 files changed, 221 insertions(+), 0 deletions(-) create mode 100644 drivers/gpio/ti-ssp-gpio.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 3143ac7..05bbe4c 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -128,6 +128,16 @@ config GPIO_VX855 additional drivers must be enabled in order to use the functionality of the device. +config GPIO_TI_SSP + tristate "TI Sequencer Serial Port - GPIO Support" + depends on MFD_TI_SSP + help + Say yes here to support a GPIO interface on TI SSP port pins. + Each SSP port translates into 4 GPIOs. + + This driver can also be built as a module. If so, the module + will be called ti-ssp-gpio. + comment "I2C GPIO expanders:" config GPIO_MAX7300 diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index bdf3dde..0e2a844 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_GPIO_PL061) += pl061.o obj-$(CONFIG_GPIO_STMPE) += stmpe-gpio.o obj-$(CONFIG_GPIO_TC35892) += tc35892-gpio.o obj-$(CONFIG_GPIO_TIMBERDALE) += timbgpio.o +obj-$(CONFIG_GPIO_TI_SSP) += ti-ssp-gpio.o obj-$(CONFIG_GPIO_TWL4030) += twl4030-gpio.o obj-$(CONFIG_GPIO_UCB1400) += ucb1400_gpio.o obj-$(CONFIG_GPIO_XILINX) += xilinx_gpio.o diff --git a/drivers/gpio/ti-ssp-gpio.c b/drivers/gpio/ti-ssp-gpio.c new file mode 100644 index 0000000..387970e --- /dev/null +++ b/drivers/gpio/ti-ssp-gpio.c @@ -0,0 +1,206 @@ +/* + * Sequencer Serial Port (SSP) based virtual GPIO driver + * + * Copyright (C) 2010 Texas Instruments Inc + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct ti_ssp_gpio_chip { + struct gpio_chip chip; + struct device *dev; + spinlock_t lock; + u8 out; + u32 iosel; +}; + +#define to_ssp_gpio_chip(c) container_of(c, struct ti_ssp_gpio_chip, chip) + +static int direction_in(struct gpio_chip *chip, unsigned gpio_num) +{ + struct ti_ssp_gpio_chip *gpio = to_ssp_gpio_chip(chip); + int error = 0; + + spin_lock(&gpio->lock); + + gpio->iosel &= ~SSP_PIN_MASK(gpio_num); + gpio->iosel |= SSP_PIN_SEL(gpio_num, SSP_IN); + + error = ti_ssp_set_iosel(gpio->dev, gpio->iosel); + + spin_unlock(&gpio->lock); + + return error; +} + +static int direction_out(struct gpio_chip *chip, unsigned gpio_num, int val) +{ + struct ti_ssp_gpio_chip *gpio = to_ssp_gpio_chip(chip); + int error; + + spin_lock(&gpio->lock); + + gpio->iosel &= ~SSP_PIN_MASK(gpio_num); + gpio->iosel |= SSP_PIN_SEL(gpio_num, SSP_OUT); + + error = ti_ssp_set_iosel(gpio->dev, gpio->iosel); + + if (error < 0) + goto error; + + if (val) + gpio->out |= BIT(gpio_num); + else + gpio->out &= ~BIT(gpio_num); + + error = ti_ssp_raw_write(gpio->dev, gpio->out); + +error: + spin_unlock(&gpio->lock); + return error; +} + +static int value_get(struct gpio_chip *chip, unsigned gpio_num) +{ + struct ti_ssp_gpio_chip *gpio = to_ssp_gpio_chip(chip); + int ret; + + spin_lock(&gpio->lock); + + ret = ti_ssp_raw_read(gpio->dev); + if (ret >= 0) + ret = !!(ret & BIT(gpio_num)); + + spin_unlock(&gpio->lock); + return ret; +} + +static void value_set(struct gpio_chip *chip, unsigned gpio_num, int val) +{ + struct ti_ssp_gpio_chip *gpio = to_ssp_gpio_chip(chip); + + spin_lock(&gpio->lock); + + if (val) + gpio->out |= BIT(gpio_num); + else + gpio->out &= ~BIT(gpio_num); + + ti_ssp_raw_write(gpio->dev, gpio->out); + + spin_unlock(&gpio->lock); +} + +static int __devinit ti_ssp_gpio_probe(struct platform_device *pdev) +{ + const struct ti_ssp_gpio_data *pdata = pdev->dev.platform_data; + struct device *dev = &pdev->dev; + struct ti_ssp_gpio_chip *gpio; + int error; + + if (!pdata) { + dev_err(dev, "platform data not found\n"); + return -EINVAL; + } + + gpio = kzalloc(sizeof(*gpio), GFP_KERNEL); + if (!gpio) { + dev_err(dev, "cannot allocate driver data\n"); + return -ENOMEM; + } + + gpio->dev = dev; + gpio->iosel = SSP_PIN_SEL(0, SSP_IN) | SSP_PIN_SEL(1, SSP_IN) | + SSP_PIN_SEL(2, SSP_IN) | SSP_PIN_SEL(3, SSP_IN); + error = ti_ssp_set_iosel(gpio->dev, gpio->iosel); + if (error < 0) { + dev_err(dev, "gpio io setup failed (%d)\n", error); + goto error; + } + + spin_lock_init(&gpio->lock); + platform_set_drvdata(pdev, gpio); + + gpio->chip.base = pdata->start; + gpio->chip.ngpio = 4; + gpio->chip.dev = &pdev->dev; + gpio->chip.label = "ti_ssp_gpio"; + gpio->chip.owner = THIS_MODULE; + gpio->chip.get = value_get; + gpio->chip.set = value_set; + gpio->chip.direction_input = direction_in; + gpio->chip.direction_output = direction_out; + + error = gpiochip_add(&gpio->chip); + if (error < 0) { + dev_err(dev, "gpio chip registration failed (%d)\n", error); + goto error; + } + + dev_info(dev, "ssp gpio interface registered\n"); + return 0; + +error: + kfree(gpio); + return error; +} + +static int __devexit ti_ssp_gpio_remove(struct platform_device *pdev) +{ + struct ti_ssp_gpio_chip *gpio = platform_get_drvdata(pdev); + int error; + + error = gpiochip_remove(&gpio->chip); + if (error < 0) + return error; + kfree(gpio); + return 0; +} + +static struct platform_driver ti_ssp_gpio_driver = { + .probe = ti_ssp_gpio_probe, + .remove = __devexit_p(ti_ssp_gpio_remove), + .driver = { + .name = "ti-ssp-gpio", + .owner = THIS_MODULE, + }, +}; + +static int __init ti_ssp_gpio_init(void) +{ + return platform_driver_register(&ti_ssp_gpio_driver); +} +module_init(ti_ssp_gpio_init); + +static void __exit ti_ssp_gpio_exit(void) +{ + platform_driver_unregister(&ti_ssp_gpio_driver); +} +module_exit(ti_ssp_gpio_exit); + +MODULE_DESCRIPTION("GPIO interface for TI-SSP"); +MODULE_AUTHOR("Cyril Chemparathy "); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ti-ssp-gpio"); diff --git a/include/linux/mfd/ti_ssp.h b/include/linux/mfd/ti_ssp.h index dbb4b43..10c65bb 100644 --- a/include/linux/mfd/ti_ssp.h +++ b/include/linux/mfd/ti_ssp.h @@ -38,6 +38,10 @@ struct ti_ssp_spi_data { void (*select)(int cs); }; +struct ti_ssp_gpio_data { + int start; +}; + /* * Sequencer port IO pin configuration bits. These do not correlate 1-1 with * the hardware. The iosel field in the port data combines iosel1 and iosel2, -- 1.7.1 ------------------------------------------------------------------------------ What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d