From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752819AbcAGD4U (ORCPT ); Wed, 6 Jan 2016 22:56:20 -0500 Received: from mail-qg0-f48.google.com ([209.85.192.48]:34925 "EHLO mail-qg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752721AbcAGDzd (ORCPT ); Wed, 6 Jan 2016 22:55:33 -0500 From: Cory Tusar To: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, gregkh@linuxfoundation.org Cc: jic23@kernel.org, vz@mleia.com, broonie@kernel.org, afd@ti.com, andrew@lunn.ch, Chris.Healy@zii.aero, Keith.Vennel@zii.aero, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Cory Tusar Subject: [PATCH v5 5/5] misc: eeprom_93xx46: Add support for a GPIO 'select' line. Date: Wed, 6 Jan 2016 22:55:04 -0500 Message-Id: <1452138904-24820-6-git-send-email-cory.tusar@pid1solutions.com> X-Mailer: git-send-email 2.4.10 In-Reply-To: <1452138904-24820-1-git-send-email-cory.tusar@pid1solutions.com> References: <1452138904-24820-1-git-send-email-cory.tusar@pid1solutions.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This commit adds support to the eeprom_93x46 driver allowing a GPIO line to function as a 'select' or 'enable' signal prior to accessing the EEPROM. Signed-off-by: Cory Tusar Tested-by: Chris Healy Reviewed-by: Vladimir Zapolskiy --- drivers/misc/eeprom/eeprom_93xx46.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/eeprom_93xx46.h | 3 +++ 2 files changed, 38 insertions(+) diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c index d50bc17..d28fac2 100644 --- a/drivers/misc/eeprom/eeprom_93xx46.c +++ b/drivers/misc/eeprom/eeprom_93xx46.c @@ -10,11 +10,13 @@ #include #include +#include #include #include #include #include #include +#include #include #include #include @@ -343,6 +345,20 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev, } static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase); +static void select_assert(void *context) +{ + struct eeprom_93xx46_dev *edev = context; + + gpiod_set_value_cansleep(edev->pdata->select, 1); +} + +static void select_deassert(void *context) +{ + struct eeprom_93xx46_dev *edev = context; + + gpiod_set_value_cansleep(edev->pdata->select, 0); +} + static const struct of_device_id eeprom_93xx46_of_table[] = { { .compatible = "eeprom-93xx46", }, { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, }, @@ -357,6 +373,8 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi) struct device_node *np = spi->dev.of_node; struct eeprom_93xx46_platform_data *pd; u32 tmp; + int gpio; + enum of_gpio_flags of_flags; int ret; pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL); @@ -381,6 +399,23 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi) if (of_property_read_bool(np, "read-only")) pd->flags |= EE_READONLY; + gpio = of_get_named_gpio_flags(np, "select-gpios", 0, &of_flags); + if (gpio_is_valid(gpio)) { + unsigned long flags = + of_flags == OF_GPIO_ACTIVE_LOW ? GPIOF_ACTIVE_LOW : 0; + + ret = devm_gpio_request_one(&spi->dev, gpio, flags, + "eeprom_93xx46_select"); + if (ret) + return ret; + + pd->select = gpio_to_desc(gpio); + pd->prepare = select_assert; + pd->finish = select_deassert; + + gpiod_direction_output(pd->select, 0); + } + if (of_id->data) { const struct eeprom_93xx46_devtype_data *data = of_id->data; diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h index 92fa4c3..885f587 100644 --- a/include/linux/eeprom_93xx46.h +++ b/include/linux/eeprom_93xx46.h @@ -3,6 +3,8 @@ * platform description for 93xx46 EEPROMs. */ +struct gpio_desc; + struct eeprom_93xx46_platform_data { unsigned char flags; #define EE_ADDR8 0x01 /* 8 bit addr. cfg */ @@ -21,4 +23,5 @@ struct eeprom_93xx46_platform_data { */ void (*prepare)(void *); void (*finish)(void *); + struct gpio_desc *select; }; -- 2.4.10