[PATCH v2 5/5] misc: eeprom_93xx46: Add support for a GPIO 'select' line.
From: Cory Tusar <hidden>
Date: 2015-11-19 03:30:11
Also in:
lkml
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
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 <redacted> --- drivers/misc/eeprom/eeprom_93xx46.c | 26 ++++++++++++++++++++++++++ include/linux/eeprom_93xx46.h | 1 + 2 files changed, 27 insertions(+)
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index 0386b03..375951f 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c@@ -10,11 +10,14 @@ #include <linux/delay.h> #include <linux/device.h> +#include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_gpio.h> #include <linux/slab.h> #include <linux/spi/spi.h> #include <linux/sysfs.h>
@@ -344,6 +347,20 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev, static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase); #ifdef CONFIG_OF +static void select_assert(void *context) +{ + struct eeprom_93xx46_dev *edev = context; + + gpiod_set_value_cansleep(gpio_to_desc(edev->pdata->select_gpio), 1); +} + +static void select_deassert(void *context) +{ + struct eeprom_93xx46_dev *edev = context; + + gpiod_set_value_cansleep(gpio_to_desc(edev->pdata->select_gpio), 0); +} + static const struct of_device_id eeprom_93xx46_of_table[] = { { .compatible = "eeprom-93xx46", }, { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
@@ -385,6 +402,15 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi) if (of_property_read_bool(np, "read-only")) pd->flags |= EE_READONLY; + ret = of_get_named_gpio(np, "select-gpios", 0); + if (ret < 0) { + pd->select_gpio = -1; + } else { + pd->select_gpio = ret; + pd->prepare = select_assert; + pd->finish = select_deassert; + } + 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..aa472c7 100644
--- a/include/linux/eeprom_93xx46.h
+++ b/include/linux/eeprom_93xx46.h@@ -21,4 +21,5 @@ struct eeprom_93xx46_platform_data { */ void (*prepare)(void *); void (*finish)(void *); + unsigned int select_gpio; };
--
2.4.10