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authorMartyn Welch <martyn.welch@ge.com>2012-03-12 17:12:58 +0000
committerKumar Gala <galak@kernel.crashing.org>2012-03-16 11:08:08 -0500
commit6518bb69f463446a1552f52093cc699497f18fe0 (patch)
tree0630ca895b251cf06eb88321fb9502b78bd7aa58 /drivers/gpio
parent330bbf485447c0cf127750eb7d68d43a73f59356 (diff)
gpio: Move GE GPIO driver to reside within GPIO subsystem
The GE GPIO driver provides basic support (set direction, read/write state) for the GPIO provided on some GE single board computers. This patch moves the driver from the 86xx specific platform directrory to the GPIO subsystem so that it can be used on non-86xx boards. Signed-off-by: Martyn Welch <martyn.welch@ge.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/Kconfig11
-rw-r--r--drivers/gpio/Makefile1
-rw-r--r--drivers/gpio/gpio-ge.c171
3 files changed, 183 insertions, 0 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d0c41188d4e..0409cf35add 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -190,6 +190,17 @@ config GPIO_VX855
additional drivers must be enabled in order to use the
functionality of the device.
+config GPIO_GE_FPGA
+ bool "GE FPGA based GPIO"
+ depends on GE_FPGA
+ help
+ Support for common GPIO functionality provided on some GE Single Board
+ Computers.
+
+ This driver provides basic support (configure as input or output, read
+ and write pin state) for GPIO implemented in a number of GE single
+ board computers.
+
comment "I2C GPIO expanders:"
config GPIO_MAX7300
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index fa10df604c0..9a8fb54ae46 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_GPIO_CS5535) += gpio-cs5535.o
obj-$(CONFIG_GPIO_DA9052) += gpio-da9052.o
obj-$(CONFIG_ARCH_DAVINCI) += gpio-davinci.o
obj-$(CONFIG_GPIO_EP93XX) += gpio-ep93xx.o
+obj-$(CONFIG_GPIO_GE_FPGA) += gpio-ge.o
obj-$(CONFIG_GPIO_IT8761E) += gpio-it8761e.o
obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o
obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o
diff --git a/drivers/gpio/gpio-ge.c b/drivers/gpio/gpio-ge.c
new file mode 100644
index 00000000000..f8e62895292
--- /dev/null
+++ b/drivers/gpio/gpio-ge.c
@@ -0,0 +1,171 @@
+/*
+ * Driver for GE FPGA based GPIO
+ *
+ * Author: Martyn Welch <martyn.welch@ge.com>
+ *
+ * 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+/* TODO
+ *
+ * Configuration of output modes (totem-pole/open-drain)
+ * Interrupt configuration - interrupts are always generated the FPGA relies on
+ * the I/O interrupt controllers mask to stop them propergating
+ */
+
+#include <linux/kernel.h>
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#define GEF_GPIO_DIRECT 0x00
+#define GEF_GPIO_IN 0x04
+#define GEF_GPIO_OUT 0x08
+#define GEF_GPIO_TRIG 0x0C
+#define GEF_GPIO_POLAR_A 0x10
+#define GEF_GPIO_POLAR_B 0x14
+#define GEF_GPIO_INT_STAT 0x18
+#define GEF_GPIO_OVERRUN 0x1C
+#define GEF_GPIO_MODE 0x20
+
+static void _gef_gpio_set(void __iomem *reg, unsigned int offset, int value)
+{
+ unsigned int data;
+
+ data = ioread32be(reg);
+ /* value: 0=low; 1=high */
+ if (value & 0x1)
+ data = data | (0x1 << offset);
+ else
+ data = data & ~(0x1 << offset);
+
+ iowrite32be(data, reg);
+}
+
+
+static int gef_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
+{
+ unsigned int data;
+ struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
+
+ data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
+ data = data | (0x1 << offset);
+ iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
+
+ return 0;
+}
+
+static int gef_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int value)
+{
+ unsigned int data;
+ struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
+
+ /* Set direction before switching to input */
+ _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
+
+ data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
+ data = data & ~(0x1 << offset);
+ iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
+
+ return 0;
+}
+
+static int gef_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ unsigned int data;
+ int state = 0;
+ struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
+
+ data = ioread32be(mmchip->regs + GEF_GPIO_IN);
+ state = (int)((data >> offset) & 0x1);
+
+ return state;
+}
+
+static void gef_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
+
+ _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
+}
+
+static int __init gef_gpio_init(void)
+{
+ struct device_node *np;
+ int retval;
+ struct of_mm_gpio_chip *gef_gpio_chip;
+
+ for_each_compatible_node(np, NULL, "gef,sbc610-gpio") {
+
+ pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
+
+ /* Allocate chip structure */
+ gef_gpio_chip = kzalloc(sizeof(*gef_gpio_chip), GFP_KERNEL);
+ if (!gef_gpio_chip) {
+ pr_err("%s: Unable to allocate structure\n",
+ np->full_name);
+ continue;
+ }
+
+ /* Setup pointers to chip functions */
+ gef_gpio_chip->gc.of_gpio_n_cells = 2;
+ gef_gpio_chip->gc.ngpio = 19;
+ gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
+ gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
+ gef_gpio_chip->gc.get = gef_gpio_get;
+ gef_gpio_chip->gc.set = gef_gpio_set;
+
+ /* This function adds a memory mapped GPIO chip */
+ retval = of_mm_gpiochip_add(np, gef_gpio_chip);
+ if (retval) {
+ kfree(gef_gpio_chip);
+ pr_err("%s: Unable to add GPIO\n", np->full_name);
+ }
+ }
+
+ for_each_compatible_node(np, NULL, "gef,sbc310-gpio") {
+
+ pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
+
+ /* Allocate chip structure */
+ gef_gpio_chip = kzalloc(sizeof(*gef_gpio_chip), GFP_KERNEL);
+ if (!gef_gpio_chip) {
+ pr_err("%s: Unable to allocate structure\n",
+ np->full_name);
+ continue;
+ }
+
+ /* Setup pointers to chip functions */
+ gef_gpio_chip->gc.of_gpio_n_cells = 2;
+ gef_gpio_chip->gc.ngpio = 6;
+ gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
+ gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
+ gef_gpio_chip->gc.get = gef_gpio_get;
+ gef_gpio_chip->gc.set = gef_gpio_set;
+
+ /* This function adds a memory mapped GPIO chip */
+ retval = of_mm_gpiochip_add(np, gef_gpio_chip);
+ if (retval) {
+ kfree(gef_gpio_chip);
+ pr_err("%s: Unable to add GPIO\n", np->full_name);
+ }
+ }
+
+ return 0;
+};
+arch_initcall(gef_gpio_init);
+
+MODULE_DESCRIPTION("GE I/O FPGA GPIO driver");
+MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com");
+MODULE_LICENSE("GPL");