| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1372046406-3127-4-git-send-email-kevin.strasser@linux.intel.com>
Date: Sun, 23 Jun 2013 21:00:05 -0700
From: Kevin Strasser <kevin.strasser@...ux.intel.com>
To: linux-kernel@...r.kernel.org
Cc: Guenter Roeck <linux@...ck-us.net>,
Kevin Strasser <kevin.strasser@...ux.intel.com>,
Kevin Strasser <strassek@...r.orst.edu>,
Darren Hart <dvhart@...ux.intel.com>,
Samuel Ortiz <sameo@...ux.intel.com>,
Michael Brunner <Michael.Brunner@...tron.com>,
Michael Brunner <mibru@....de>,
Chris Healy <chealy@...co-us.com>,
Thomas Gleixner <tglx@...utronix.de>,
Dirk Hohndel <Dirk.Hohndel@...el.com>,
Wolfram Sang <wsa@...-dreams.de>,
Ben Dooks <ben-linux@...ff.org>,
Grant Likely <grant.likely@...retlab.ca>,
Linus Walleij <linus.walleij@...aro.org>,
Wim Van Sebroeck <wim@...ana.be>
Subject: [PATCH v3 3/4] gpio: Kontron PLD gpio driver
From: Guenter Roeck <linux@...ck-us.net>
Add gpio support for the on-board PLD found on some Kontron embedded modules.
Originally-From: Michael Brunner <michael.brunner@...tron.com>
Signed-off-by: Guenter Roeck <linux@...ck-us.net>
Signed-off-by: Kevin Strasser <kevin.strasser@...ux.intel.com>
Acked-by: Darren Hart <dvhart@...ux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@...aro.org>
---
drivers/gpio/Kconfig | 12 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-kempld.c | 225 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 238 insertions(+)
create mode 100644 drivers/gpio/gpio-kempld.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 93aaadf..e94b266 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -658,6 +658,18 @@ config GPIO_UCB1400
This enables support for the Philips UCB1400 GPIO pins.
The UCB1400 is an AC97 audio codec.
+comment "LPC GPIO expanders:"
+
+config GPIO_KEMPLD
+ tristate "Kontron ETX / COMexpress GPIO"
+ depends on MFD_KEMPLD
+ help
+ This enables support for the PLD GPIO interface on some Kontron ETX
+ and COMexpress (ETXexpress) modules.
+
+ This driver can also be built as a module. If so, the module will be
+ called gpio-kempld.
+
comment "MODULbus GPIO expanders:"
config GPIO_JANZ_TTL
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 22e07bc..758c348 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_GPIO_GE_FPGA) += gpio-ge.o
obj-$(CONFIG_GPIO_ICH) += gpio-ich.o
obj-$(CONFIG_GPIO_IT8761E) += gpio-it8761e.o
obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o
+obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o
obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o
obj-$(CONFIG_GPIO_LANGWELL) += gpio-langwell.o
obj-$(CONFIG_ARCH_LPC32XX) += gpio-lpc32xx.o
diff --git a/drivers/gpio/gpio-kempld.c b/drivers/gpio/gpio-kempld.c
new file mode 100644
index 0000000..1bdc3a2
--- /dev/null
+++ b/drivers/gpio/gpio-kempld.c
@@ -0,0 +1,225 @@
+/*
+ * Kontron PLD GPIO driver
+ *
+ * Copyright (c) 2010-2013 Kontron Europe GmbH
+ * Author: Michael Brunner <michael.brunner@...tron.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 2 as published
+ * by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/mfd/kempld.h>
+
+#define KEMPLD_GPIO_MAX_NUM 16
+#define KEMPLD_GPIO_MASK(x) (1 << ((x) % 8))
+#define KEMPLD_GPIO_DIR_NUM(x) (0x40 + (x) / 8)
+#define KEMPLD_GPIO_LVL_NUM(x) (0x42 + (x) / 8)
+#define KEMPLD_GPIO_EVT_LVL_EDGE 0x46
+#define KEMPLD_GPIO_IEN 0x4A
+
+struct kempld_gpio_data {
+ struct gpio_chip chip;
+ struct kempld_device_data *pld;
+};
+
+/*
+ * Set or clear GPIO bit
+ * kempld_get_mutex must be called prior to calling this function.
+ */
+static void kempld_gpio_bitop(struct kempld_device_data *pld,
+ u8 reg, u8 bit, u8 val)
+{
+ u8 status;
+
+ status = kempld_read8(pld, reg);
+ if (val)
+ status |= (1 << bit);
+ else
+ status &= ~(1 << bit);
+ kempld_write8(pld, reg, status);
+}
+
+static int kempld_gpio_get_bit(struct kempld_device_data *pld, u8 reg, u8 bit)
+{
+ u8 status;
+
+ kempld_get_mutex(pld);
+ status = kempld_read8(pld, reg);
+ kempld_release_mutex(pld);
+
+ return !!(status & (1 << bit));
+}
+
+static int kempld_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct kempld_gpio_data *gpio
+ = container_of(chip, struct kempld_gpio_data, chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ return kempld_gpio_get_bit(pld, KEMPLD_GPIO_LVL_NUM(offset),
+ KEMPLD_GPIO_MASK(offset));
+}
+
+static void kempld_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct kempld_gpio_data *gpio
+ = container_of(chip, struct kempld_gpio_data, chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ kempld_get_mutex(pld);
+ kempld_gpio_bitop(pld, KEMPLD_GPIO_LVL_NUM(offset),
+ KEMPLD_GPIO_MASK(offset), value);
+ kempld_release_mutex(pld);
+}
+
+static int kempld_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct kempld_gpio_data *gpio
+ = container_of(chip, struct kempld_gpio_data, chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ kempld_get_mutex(pld);
+ kempld_gpio_bitop(pld, KEMPLD_GPIO_DIR_NUM(offset),
+ KEMPLD_GPIO_MASK(offset), 0);
+ kempld_release_mutex(pld);
+
+ return 0;
+}
+
+static int kempld_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ struct kempld_gpio_data *gpio
+ = container_of(chip, struct kempld_gpio_data, chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ kempld_get_mutex(pld);
+ kempld_gpio_bitop(pld, KEMPLD_GPIO_LVL_NUM(offset),
+ KEMPLD_GPIO_MASK(offset), value);
+ kempld_gpio_bitop(pld, KEMPLD_GPIO_DIR_NUM(offset),
+ KEMPLD_GPIO_MASK(offset), 1);
+ kempld_release_mutex(pld);
+
+ return 0;
+}
+
+static int kempld_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
+{
+ struct kempld_gpio_data *gpio
+ = container_of(chip, struct kempld_gpio_data, chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ return kempld_gpio_get_bit(pld, KEMPLD_GPIO_DIR_NUM(offset),
+ KEMPLD_GPIO_MASK(offset));
+}
+
+static int kempld_gpio_pincount(struct kempld_device_data *pld)
+{
+ u16 evt, evt_back;
+
+ kempld_get_mutex(pld);
+
+ /* Backup event register as it might be already initialized */
+ evt_back = kempld_read16(pld, KEMPLD_GPIO_EVT_LVL_EDGE);
+ /* Clear event register */
+ kempld_write16(pld, KEMPLD_GPIO_EVT_LVL_EDGE, 0x0000);
+ /* Read back event register */
+ evt = kempld_read16(pld, KEMPLD_GPIO_EVT_LVL_EDGE);
+ /* Restore event register */
+ kempld_write16(pld, KEMPLD_GPIO_EVT_LVL_EDGE, evt_back);
+
+ kempld_release_mutex(pld);
+
+ return evt ? __ffs(evt) : 16;
+}
+
+static int kempld_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct kempld_device_data *pld = dev_get_drvdata(dev->parent);
+ struct kempld_platform_data *pdata = pld->dev->platform_data;
+ struct kempld_gpio_data *gpio;
+ struct gpio_chip *chip;
+ int ret;
+
+ if (pld->info.spec_major < 2) {
+ dev_err(dev,
+ "Driver only supports GPIO devices compatible to PLD spec. rev. 2.0 or higher\n");
+ return -ENODEV;
+ }
+
+ gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
+ if (gpio == NULL)
+ return -ENOMEM;
+
+ gpio->pld = pld;
+
+ platform_set_drvdata(pdev, gpio);
+
+ chip = &gpio->chip;
+ chip->label = "gpio-kempld";
+ chip->owner = THIS_MODULE;
+ chip->dev = dev;
+ chip->can_sleep = 1;
+ if (pdata && pdata->gpio_base)
+ chip->base = pdata->gpio_base;
+ else
+ chip->base = -1;
+ chip->direction_input = kempld_gpio_direction_input;
+ chip->direction_output = kempld_gpio_direction_output;
+ chip->get_direction = kempld_gpio_get_direction;
+ chip->get = kempld_gpio_get;
+ chip->set = kempld_gpio_set;
+ chip->ngpio = kempld_gpio_pincount(pld);
+ if (chip->ngpio == 0) {
+ dev_err(dev, "No GPIO pins detected\n");
+ return -ENODEV;
+ }
+
+ ret = gpiochip_add(chip);
+ if (ret) {
+ dev_err(dev, "Could not register GPIO chip\n");
+ return ret;
+ }
+
+ dev_info(dev, "GPIO functionality initialized with %d pins\n",
+ chip->ngpio);
+
+ return 0;
+}
+
+static int kempld_gpio_remove(struct platform_device *pdev)
+{
+ struct kempld_gpio_data *gpio = platform_get_drvdata(pdev);
+
+ return gpiochip_remove(&gpio->chip);
+}
+
+static struct platform_driver kempld_gpio_driver = {
+ .driver = {
+ .name = "gpio-kempld",
+ .owner = THIS_MODULE,
+ },
+ .probe = kempld_gpio_probe,
+ .remove = kempld_gpio_remove,
+};
+
+module_platform_driver(kempld_gpio_driver);
+
+MODULE_DESCRIPTION("KEM PLD GPIO Driver");
+MODULE_AUTHOR("Michael Brunner <michael.brunner@...tron.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio-kempld");
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists