summaryrefslogtreecommitdiff
path: root/drivers/gpio
diff options
context:
space:
mode:
authorJoachim Foerster <joachim.foerster@missinglinkelectronics.com>2011-10-21 15:48:50 +0200
committerThomas Chou <thomas@wytron.com.tw>2011-10-28 09:50:49 +0800
commit03d67e127685f65513e7b78dacbd4ccaf01053f6 (patch)
tree689e13ece8dd47b9c03354ac97fcd9d13127c756 /drivers/gpio
parentf956ad98b2ba10901b6ea04983e679bc5ddc4d7a (diff)
gpio: Add driver for Altera's PIO core
This driver may handle multiple PIO cores and thus needs to be setup by calling the altera_pio_init() function within the early board setup routine. The driver comes with some extras, see below the copyleft header. Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com> Tested-by: Thomas Chou <thomas@wytron.com.tw> Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/Makefile1
-rw-r--r--drivers/gpio/altera_pio.c299
2 files changed, 300 insertions, 0 deletions
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index f505813d0ea..b5264d1da56 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -35,6 +35,7 @@ COBJS-$(CONFIG_PCA9698) += pca9698.o
COBJS-$(CONFIG_S5P) += s5p_gpio.o
COBJS-$(CONFIG_TEGRA2_GPIO) += tegra2_gpio.o
COBJS-$(CONFIG_DA8XX_GPIO) += da8xx_gpio.o
+COBJS-$(CONFIG_ALTERA_PIO) += altera_pio.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)
diff --git a/drivers/gpio/altera_pio.c b/drivers/gpio/altera_pio.c
new file mode 100644
index 00000000000..fb037607355
--- /dev/null
+++ b/drivers/gpio/altera_pio.c
@@ -0,0 +1,299 @@
+/*
+ * Driver for Altera's PIO ip core
+ *
+ * Copyright (C) 2011 Missing Link Electronics
+ * Joachim Foerster <joachim@missinglinkelectronics.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * To use this driver, in your board's config. header:
+ * #define CONFIG_ALTERA_PIO
+ * #define CONFIG_SYS_ALTERA_PIO_NUM <number-of-pio-cores>
+ * #define CONFIG_SYS_ALTERA_PIO_GPIO_NUM <total-number-of-gpios>
+ * And in your board's early setup routine:
+ * altera_pio_init(<baseaddr>, <width>, 'i'|'o'|'t',
+ * <reset-value>, <neg-mask>, "label");
+ * - 'i'|'o'|'t': PIO is input-only/output-only/tri-state
+ * - <reset-value>: for correct initial status display, output-only
+ * - <neg-mask> is meant to be used to in cases of active-low
+ * GPIOs, such as LEDs and buttons (on/pressed == 0). Each bit
+ * which is 1 in <neg-mask> inverts the corresponding GPIO's value
+ * before set/after get. So: gpio_set_value(gpio, 1) => LED on .
+ *
+ * Do NOT define CONFIG_SYS_GPIO_BASE !
+ *
+ * Optionally, in your board's config. header:
+ * - To force a GPIO numbering scheme like in Linux ...
+ * #define CONFIG_GPIO_DOWNTO_NUMBERING
+ * ... starting with 255 (default)
+ * #define CONFIG_GPIO_DOWNTO_MAX 255
+ */
+#include <common.h>
+#include <asm/io.h>
+#include <asm/gpio.h>
+
+#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
+#ifndef CONFIG_GPIO_DOWNTO_MAX
+#define CONFIG_GPIO_DOWNTO_MAX 255
+#endif
+#endif
+
+#define ALTERA_PIO_DATA 0x0
+#define ALTERA_PIO_DIR 0x4
+
+#define GPIO_LABEL_SIZE 9
+
+
+static struct altera_pio {
+ u32 base;
+ u8 width;
+ char iot;
+ u32 negmask;
+ u32 sh_data;
+ u32 sh_dir;
+ int gidx;
+ char label[GPIO_LABEL_SIZE];
+} pios[CONFIG_SYS_ALTERA_PIO_NUM];
+
+static int pio_num;
+
+static struct altera_pio_gpio {
+ unsigned num;
+ struct altera_pio *pio;
+ char reqlabel[GPIO_LABEL_SIZE];
+} gpios[CONFIG_SYS_ALTERA_PIO_GPIO_NUM];
+
+static int pio_gpio_num;
+
+
+static int altera_pio_gidx(unsigned gpio)
+{
+ int i;
+
+ for (i = 0; i < pio_gpio_num; ++i) {
+ if (gpio == gpios[i].num)
+ break;
+ }
+ if (i >= pio_gpio_num)
+ return -1;
+ return i;
+}
+
+static struct altera_pio *altera_pio_get_and_mask(unsigned gpio, u32 *mask)
+{
+ int gidx = altera_pio_gidx(gpio);
+ if (gidx < 0)
+ return NULL;
+ if (mask)
+ *mask = 1 << (gidx - gpios[gidx].pio->gidx);
+ return gpios[gidx].pio;
+}
+
+#define altera_pio_use_gidx(_gidx, _reqlabel) \
+ { strncpy(gpios[_gidx].reqlabel, _reqlabel, GPIO_LABEL_SIZE); }
+#define altera_pio_unuse_gidx(_gidx) { gpios[_gidx].reqlabel[0] = '\0'; }
+#define altera_pio_is_gidx_used(_gidx) (gpios[_gidx].reqlabel[0] != '\0')
+
+static int altera_pio_gpio_init(struct altera_pio *pio, u8 width)
+{
+ u8 gidx = pio_gpio_num;
+ int i;
+
+ if (!width)
+ return -1;
+ if ((pio_gpio_num + width) > CONFIG_SYS_ALTERA_PIO_GPIO_NUM)
+ return -1;
+
+ for (i = 0; i < width; ++i) {
+#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
+ gpios[pio_gpio_num + i].num = \
+ CONFIG_GPIO_DOWNTO_MAX + 1 - gidx - width + i;
+#else
+ gpios[pio_gpio_num + i].num = pio_gpio_num + i;
+#endif
+ gpios[pio_gpio_num + i].pio = pio;
+ altera_pio_unuse_gidx(pio_gpio_num + i);
+ }
+ pio_gpio_num += width;
+ return gidx;
+}
+
+int altera_pio_init(u32 base, u8 width, char iot, u32 rstval, u32 negmask,
+ const char *label)
+{
+ if (pio_num >= CONFIG_SYS_ALTERA_PIO_NUM)
+ return -1;
+
+ pios[pio_num].base = base;
+ pios[pio_num].width = width;
+ pios[pio_num].iot = iot;
+ switch (iot) {
+ case 'i':
+ /* input only */
+ pios[pio_num].sh_dir = 0;
+ pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
+ break;
+ case 'o':
+ /* output only */
+ pios[pio_num].sh_dir = 0xffffffff & ((1 << width) - 1);
+ pios[pio_num].sh_data = rstval;
+ break;
+ case 't':
+ /* bidir, tri-state */
+ pios[pio_num].sh_dir = readl(base + ALTERA_PIO_DIR);
+ pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
+ break;
+ default:
+ return -1;
+ }
+ pios[pio_num].negmask = negmask & ((1 << width) - 1);
+ pios[pio_num].gidx = altera_pio_gpio_init(&pios[pio_num], width);
+ if (pios[pio_num].gidx < 0)
+ return -1;
+ strncpy(pios[pio_num].label, label, GPIO_LABEL_SIZE);
+ return pio_num++;
+}
+
+void altera_pio_info(void)
+{
+ int i;
+ int j;
+ int gidx;
+ u32 mask;
+
+ for (i = 0; i < pio_num; ++i) {
+ printf("Altera PIO % 2d, @0x%08x, "
+ "width: %u, label: %s\n",
+ i, pios[i].base, pios[i].width, pios[i].label);
+ gidx = pios[i].gidx;
+ for (j = gidx; j < (gidx + pios[i].width); ++j) {
+ mask = 1 << (j - gidx);
+ printf("\tGPIO % 4d: %s %s [%c] %s\n",
+ gpios[j].num,
+ gpios[j].pio->sh_dir & mask ? "out" : " in",
+ gpio_get_value(gpios[j].num) ? "set" : "clr",
+ altera_pio_is_gidx_used(j) ? 'x' : ' ',
+ gpios[j].reqlabel);
+ }
+ }
+}
+
+
+int gpio_request(unsigned gpio, const char *label)
+{
+ int gidx = altera_pio_gidx(gpio);
+ if (gidx < 0)
+ return gidx;
+ if (altera_pio_is_gidx_used(gidx))
+ return -1;
+
+ altera_pio_use_gidx(gidx, label);
+ return 0;
+}
+
+int gpio_free(unsigned gpio)
+{
+ int gidx = altera_pio_gidx(gpio);
+ if (gidx < 0)
+ return gidx;
+ if (!altera_pio_is_gidx_used(gidx))
+ return -1;
+
+ altera_pio_unuse_gidx(gidx);
+ return 0;
+}
+
+int gpio_direction_input(unsigned gpio)
+{
+ u32 mask;
+ struct altera_pio *pio;
+
+ pio = altera_pio_get_and_mask(gpio, &mask);
+ if (!pio)
+ return -1;
+ if (pio->iot == 'o')
+ return -1;
+
+ writel(pio->sh_dir &= ~mask, pio->base + ALTERA_PIO_DIR);
+ return 0;
+}
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+ u32 mask;
+ struct altera_pio *pio;
+
+ pio = altera_pio_get_and_mask(gpio, &mask);
+ if (!pio)
+ return -1;
+ if (pio->iot == 'i')
+ return -1;
+
+ value = (pio->negmask & mask) ? !value : value;
+ if (value)
+ pio->sh_data |= mask;
+ else
+ pio->sh_data &= ~mask;
+ writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
+ writel(pio->sh_dir |= mask, pio->base + ALTERA_PIO_DIR);
+ return 0;
+}
+
+int gpio_get_value(unsigned gpio)
+{
+ u32 mask;
+ struct altera_pio *pio;
+ u32 val;
+
+ pio = altera_pio_get_and_mask(gpio, &mask);
+ if (!pio)
+ return -1;
+
+ if ((pio->sh_dir & mask) || (pio->iot == 'o'))
+ val = pio->sh_data & mask;
+ else
+ val = readl(pio->base + ALTERA_PIO_DATA) & mask;
+ return (pio->negmask & mask) ? !val : val;
+}
+
+void gpio_set_value(unsigned gpio, int value)
+{
+ u32 mask;
+ struct altera_pio *pio;
+
+ pio = altera_pio_get_and_mask(gpio, &mask);
+ if (!pio)
+ return;
+ if (pio->iot == 'i')
+ return;
+
+ value = (pio->negmask & mask) ? !value : value;
+ if (value)
+ pio->sh_data |= mask;
+ else
+ pio->sh_data &= ~mask;
+ writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
+ return;
+}
+
+int gpio_is_valid(int number)
+{
+ int gidx = altera_pio_gidx(number);
+
+ if (gidx < 0)
+ return 1;
+ return 0;
+}