[PATCH v4 3/3] gpio: add Intel SCH GPIO controller driver

Denis Turischev
2010-03-01T17:02:00Z

v2: there is no acpi_check_region, it will be implemented in mfd-core
v3: patch refreshed against the latest Linus tree
v4: refreshed again

Signed-off-by: Denis Turischev <denis@compulab.co.il>
---
drivers/gpio/Kconfig | 16 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/sch_gpio.c | 282 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 299 insertions(+), 0 deletions(-)
create mode 100644 drivers/gpio/sch_gpio.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 1f1d88a..1730068 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -85,6 +85,22 @@ config GPIO_VR41XX
help
Say yes here to support the NEC VR4100 series General-purpose I/O Uint

+config GPIO_SCH
+ tristate "Intel SCH GPIO"
+ depends on GPIOLIB
+ select LPC_SCH
+ help
+ Say yes here to support GPIO interface on Intel Poulsbo SCH.
+ The Intel SCH contains a total of 14 GPIO pins. Ten GPIOs are
+ powered by the core power rail and are turned off during sleep
+ modes (S3 and higher). The remaining four GPIOs are powered by
+ the Intel SCH suspend power supply. These GPIOs remain
+ active during S3. The suspend powered GPIOs can be used to wake the
+ system from the Suspend-to-RAM state.
+
+ This driver can also be built as a module. If so, the module
+ will be called sch-gpio.
+
comment "I2C GPIO expanders:"

config GPIO_MAX732X
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4868723..aa1d06e 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -22,3 +22,4 @@ obj-$(CONFIG_GPIO_CS5535) += cs5535-gpio.o
obj-$(CONFIG_GPIO_BT8XX) += bt8xxgpio.o
obj-$(CONFIG_GPIO_VR41XX) += vr41xx_giu.o
obj-$(CONFIG_GPIO_WM831X) += wm831x-gpio.o
+obj-$(CONFIG_GPIO_SCH) += sch_gpio.o
diff --git a/drivers/gpio/sch_gpio.c b/drivers/gpio/sch_gpio.c
new file mode 100644
index 0000000..761071a
--- /dev/null
+++ b/drivers/gpio/sch_gpio.c
@@ -0,0 +1,282 @@
+/*
+ * sch_gpio.c - GPIO interface for Intel Poulsbo SCH
+ *
+ * Copyright (c) 2010 CompuLab Ltd
+ * Author: Denis Turischev <denis@compulab.co.il>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/acpi.h>
+#include <linux/platform_device.h>
+
+#include <linux/gpio.h>
+
+static DEFINE_SPINLOCK(gpio_lock);
+
+#define CGEN (0x00)
+#define CGIO (0x04)
+#define CGLV (0x08)
+
+#define RGEN (0x20)
+#define RGIO (0x24)
+#define RGLV (0x28)
+
+static unsigned short gpio_ba;
+
+static int sch_gpio_core_direction_in(struct gpio_chip *gc, unsigned gpio_num)
+{
+ u8 curr_dirs;
+ unsigned short offset, bit;
+
+ spin_lock(&gpio_lock);
+
+ offset = CGIO + gpio_num / 8;
+ bit = gpio_num % 8;
+
+ curr_dirs = inb(gpio_ba + offset);
+
+ if (!(curr_dirs & (1 << bit)))
+ outb(curr_dirs | (1 << bit), gpio_ba + offset);
+
+ spin_unlock(&gpio_lock);
+ return 0;
+}
+
+static int sch_gpio_core_get(struct gpio_chip *gc, unsigned gpio_num)
+{
+ int res;
+ unsigned short offset, bit;
+
+ offset = CGLV + gpio_num / 8;
+ bit = gpio_num % 8;
+
+ res = !!(inb(gpio_ba + offset) & (1 << bit));
+ return res;
+}
+
+static void sch_gpio_core_set(struct gpio_chip *gc, unsigned gpio_num, int val)
+{
+ u8 curr_vals;
+ unsigned short offset, bit;
+
+ spin_lock(&gpio_lock);
+
+ offset = CGLV + gpio_num / 8;
+ bit = gpio_num % 8;
+
+ curr_vals = inb(gpio_ba + offset);
+
+ if (val)
+ outb(curr_vals | (1 << bit), gpio_ba + offset);
+ else
+ outb((curr_vals & ~(1 << bit)), gpio_ba + offset);
+ spin_unlock(&gpio_lock);
+}
+
+static int sch_gpio_core_direction_out(struct gpio_chip *gc,
+ unsigned gpio_num, int val)
+{
+ u8 curr_dirs;
+ unsigned short offset, bit;
+
+ sch_gpio_core_set(gc, gpio_num, val);
+
+ spin_lock(&gpio_lock);
+
+ offset = CGIO + gpio_num / 8;
+ bit = gpio_num % 8;
+
+ curr_dirs = inb(gpio_ba + offset);
+ if (curr_dirs & (1 << bit))
+ outb(curr_dirs & ~(1 << bit), gpio_ba + offset);
+
+ spin_unlock(&gpio_lock);
+ return 0;
+}
+
+static struct gpio_chip sch_gpio_core = {
+ .label = "sch_gpio_core",
+ .owner = THIS_MODULE,
+ .direction_input = sch_gpio_core_direction_in,
+ .get = sch_gpio_core_get,
+ .direction_output = sch_gpio_core_direction_out,
+ .set = sch_gpio_core_set,
+};
+
+static int sch_gpio_resume_direction_in(struct gpio_chip *gc,
+ unsigned gpio_num)
+{
+ u8 curr_dirs;
+
+ spin_lock(&gpio_lock);
+
+ curr_dirs = inb(gpio_ba + RGIO);
+
+ if (!(curr_dirs & (1 << gpio_num)))
+ outb(curr_dirs | (1 << gpio_num) , gpio_ba + RGIO);
+
+ spin_unlock(&gpio_lock);
+ return 0;
+}
+
+static int sch_gpio_resume_get(struct gpio_chip *gc, unsigned gpio_num)
+{
+ return !!(inb(gpio_ba + RGLV) & (1 << gpio_num));
+}
+
+static void sch_gpio_resume_set(struct gpio_chip *gc,
+ unsigned gpio_num, int val)
+{
+ u8 curr_vals;
+
+ spin_lock(&gpio_lock);
+
+ curr_vals = inb(gpio_ba + RGLV);
+
+ if (val)
+ outb(curr_vals | (1 << gpio_num), gpio_ba + RGLV);
+ else
+ outb((curr_vals & ~(1 << gpio_num)), gpio_ba + RGLV);
+
+ spin_unlock(&gpio_lock);
+}
+
+static int sch_gpio_resume_direction_out(struct gpio_chip *gc,
+ unsigned gpio_num, int val)
+{
+ u8 curr_dirs;
+
+ sch_gpio_resume_set(gc, gpio_num, val);
+
+ spin_lock(&gpio_lock);
+
+ curr_dirs = inb(gpio_ba + RGIO);
+ if (curr_dirs & (1 << gpio_num))
+ outb(curr_dirs & ~(1 << gpio_num), gpio_ba + RGIO);
+
+ spin_unlock(&gpio_lock);
+ return 0;
+}
+
+static struct gpio_chip sch_gpio_resume = {
+ .label = "sch_gpio_resume",
+ .owner = THIS_MODULE,
+ .direction_input = sch_gpio_resume_direction_in,
+ .get = sch_gpio_resume_get,
+ .direction_output = sch_gpio_resume_direction_out,
+ .set = sch_gpio_resume_set,
+};
+
+static int __devinit sch_gpio_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ int err;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (!res)
+ return -EBUSY;
+
+ if (!request_region(res->start, resource_size(res), pdev->name))
+ return -EBUSY;
+
+ gpio_ba = res->start;
+
+ sch_gpio_core.base = 0;
+ sch_gpio_core.ngpio = 10;
+ sch_gpio_core.dev = &pdev->dev;
+
+ sch_gpio_resume.base = 10;
+ sch_gpio_resume.ngpio = 4;
+ sch_gpio_resume.dev = &pdev->dev;
+
+ err = gpiochip_add(&sch_gpio_core);
+ if (err < 0)
+ goto err_sch_gpio_core;
+
+ err = gpiochip_add(&sch_gpio_resume);
+ if (err < 0)
+ goto err_sch_gpio_resume;
+
+ /*
+ * GPIO[6:0] enabled by default
+ * GPIO7 is configured by the CMC as SLPIOVR
+ * Enable GPIO[9:8] core powered gpios explicitly
+ */
+ outb(0x3, gpio_ba + CGEN + 1);
+ /*
+ * SUS_GPIO[2:0] enabled by default
+ * Enable SUS_GPIO3 resume powered gpio explicitly
+ */
+ outb(0x8, gpio_ba + RGEN);
+
+ return 0;
+
+err_sch_gpio_resume:
+ gpiochip_remove(&sch_gpio_core);
+
+err_sch_gpio_core:
+ release_region(res->start, resource_size(res));
+ gpio_ba = 0;
+
+ return err;
+}
+
+static int __devexit sch_gpio_remove(struct platform_device *pdev)
+{
+ struct resource *res;
+ if (gpio_ba) {
+ gpiochip_remove(&sch_gpio_core);
+ gpiochip_remove(&sch_gpio_resume);
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+
+ release_region(res->start, resource_size(res));
+ gpio_ba = 0;
+ }
+
+ return 0;
+}
+
+static struct platform_driver sch_gpio_driver = {
+ .driver = {
+ .name = "sch_gpio",
+ .owner = THIS_MODULE,
+ },
+ .probe = sch_gpio_probe,
+ .remove = __devexit_p(sch_gpio_remove),
+};
+
+static int __init sch_gpio_init(void)
+{
+ return platform_driver_register(&sch_gpio_driver);
+}
+
+static void __exit sch_gpio_exit(void)
+{
+ platform_driver_unregister(&sch_gpio_driver);
+}
+
+module_init(sch_gpio_init);
+module_exit(sch_gpio_exit);
+
+MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
+MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:sch_gpio");
--
1.6.3.3