[PATCH v7 07/15] ARM: mxs: Add gpio support
Shawn Guo
shawn.guo at freescale.com
Sat Dec 18 08:39:31 EST 2010
MXS-based SoCs implement gpio support in block PINCTRL.
Signed-off-by: Shawn Guo <shawn.guo at freescale.com>
---
Changes for v7:
- Switch over to use gpiolib __gpio_to_irq()
Changes for v6:
- Use __mxs_setl() and __mxs_clrl() for bit set/clear
- Rename functions for not using leading underscore
- Add mxs_ to some functions name to align naming scheme
- Introduce variables pin_mask and pin_addr to make code look better
- Remove PINCTRL_PIN2IRQ from irq_stat assignment
- Add comment for clearing status bit in IRQSTAT
- Set up irq handler before registering gpio chip
Changes for v5:
- Leave PIN2IRQ set when disabling gpio IRQ to avoid
losting interrupt
Changes for v3:
- include/mach/gpio.h: remove the inclusion of hardware.h
- gpio.c: change inclusion of hardware.h to mx23.h plus mx28.h
- Remove spinlock totally since SET/CLE can be used in all the
gpio register access
Changes for v2:
- Create arch/arm/mach-mxs/gpio.h to accommodate stuff private for mach-mxs
- Use GPIO_INT_LEV_MASK and GPIO_INT_POL_MASK instead of constant
- Remove both edges IRQ support which is not needed
- Use SET and CLR register of PINCTRL_DOE in _set_gpio_direction()
- Use pr_info over printk(KERN_INFO)
arch/arm/mach-mxs/gpio.c | 325 +++++++++++++++++++++++++++++++++
arch/arm/mach-mxs/gpio.h | 34 ++++
arch/arm/mach-mxs/include/mach/gpio.h | 35 ++++
3 files changed, 394 insertions(+), 0 deletions(-)
create mode 100644 arch/arm/mach-mxs/gpio.c
create mode 100644 arch/arm/mach-mxs/gpio.h
create mode 100644 arch/arm/mach-mxs/include/mach/gpio.h
diff --git a/arch/arm/mach-mxs/gpio.c b/arch/arm/mach-mxs/gpio.c
new file mode 100644
index 0000000..d7ad7a6
--- /dev/null
+++ b/arch/arm/mach-mxs/gpio.c
@@ -0,0 +1,325 @@
+/*
+ * MXC GPIO support. (c) 2008 Daniel Mack <daniel at caiaq.de>
+ * Copyright 2008 Juergen Beisert, kernel at pengutronix.de
+ *
+ * Based on code from Freescale,
+ * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <mach/mx23.h>
+#include <mach/mx28.h>
+#include <asm-generic/bug.h>
+
+#include "gpio.h"
+
+static struct mxs_gpio_port *mxs_gpio_ports;
+static int gpio_table_size;
+
+#define PINCTRL_DOUT(n) ((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
+#define PINCTRL_DIN(n) ((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
+#define PINCTRL_DOE(n) ((cpu_is_mx23() ? 0x0700 : 0x0b00) + (n) * 0x10)
+#define PINCTRL_PIN2IRQ(n) ((cpu_is_mx23() ? 0x0800 : 0x1000) + (n) * 0x10)
+#define PINCTRL_IRQEN(n) ((cpu_is_mx23() ? 0x0900 : 0x1100) + (n) * 0x10)
+#define PINCTRL_IRQLEV(n) ((cpu_is_mx23() ? 0x0a00 : 0x1200) + (n) * 0x10)
+#define PINCTRL_IRQPOL(n) ((cpu_is_mx23() ? 0x0b00 : 0x1300) + (n) * 0x10)
+#define PINCTRL_IRQSTAT(n) ((cpu_is_mx23() ? 0x0c00 : 0x1400) + (n) * 0x10)
+
+#define GPIO_INT_FALL_EDGE 0x0
+#define GPIO_INT_LOW_LEV 0x1
+#define GPIO_INT_RISE_EDGE 0x2
+#define GPIO_INT_HIGH_LEV 0x3
+#define GPIO_INT_LEV_MASK (1 << 0)
+#define GPIO_INT_POL_MASK (1 << 1)
+
+/* Note: This driver assumes 32 GPIOs are handled in one register */
+
+static void clear_gpio_irqstatus(struct mxs_gpio_port *port, u32 index)
+{
+ __mxs_clrl(1 << index, port->base + PINCTRL_IRQSTAT(port->id));
+}
+
+static void set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
+ int enable)
+{
+ if (enable) {
+ __mxs_setl(1 << index, port->base + PINCTRL_IRQEN(port->id));
+ __mxs_setl(1 << index, port->base + PINCTRL_PIN2IRQ(port->id));
+ } else {
+ __mxs_clrl(1 << index, port->base + PINCTRL_IRQEN(port->id));
+ }
+}
+
+static void mxs_gpio_ack_irq(u32 irq)
+{
+ u32 gpio = irq_to_gpio(irq);
+ clear_gpio_irqstatus(&mxs_gpio_ports[gpio / 32], gpio & 0x1f);
+}
+
+static void mxs_gpio_mask_irq(u32 irq)
+{
+ u32 gpio = irq_to_gpio(irq);
+ set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 0);
+}
+
+static void mxs_gpio_unmask_irq(u32 irq)
+{
+ u32 gpio = irq_to_gpio(irq);
+ set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 1);
+}
+
+static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset);
+
+static int mxs_gpio_set_irq_type(u32 irq, u32 type)
+{
+ u32 gpio = irq_to_gpio(irq);
+ u32 pin_mask = 1 << (gpio & 31);
+ struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
+ void __iomem *pin_addr;
+ int edge;
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ edge = GPIO_INT_RISE_EDGE;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ edge = GPIO_INT_FALL_EDGE;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ edge = GPIO_INT_LOW_LEV;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ edge = GPIO_INT_HIGH_LEV;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* set level or edge */
+ pin_addr = port->base + PINCTRL_IRQLEV(port->id);
+ if (edge & GPIO_INT_LEV_MASK)
+ __mxs_setl(pin_mask, pin_addr);
+ else
+ __mxs_clrl(pin_mask, pin_addr);
+
+ /* set polarity */
+ pin_addr = port->base + PINCTRL_IRQPOL(port->id);
+ if (edge & GPIO_INT_POL_MASK)
+ __mxs_setl(pin_mask, pin_addr);
+ else
+ __mxs_clrl(pin_mask, pin_addr);
+
+ clear_gpio_irqstatus(port, gpio & 0x1f);
+
+ return 0;
+}
+
+/* MXS has one interrupt *per* gpio port */
+static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
+{
+ u32 irq_stat;
+ struct mxs_gpio_port *port = (struct mxs_gpio_port *)get_irq_data(irq);
+ u32 gpio_irq_no_base = port->virtual_irq_start;
+
+ irq_stat = __raw_readl(port->base + PINCTRL_IRQSTAT(port->id)) &
+ __raw_readl(port->base + PINCTRL_IRQEN(port->id));
+
+ while (irq_stat != 0) {
+ int irqoffset = fls(irq_stat) - 1;
+ generic_handle_irq(gpio_irq_no_base + irqoffset);
+ irq_stat &= ~(1 << irqoffset);
+ }
+}
+
+/*
+ * Set interrupt number "irq" in the GPIO as a wake-up source.
+ * While system is running, all registered GPIO interrupts need to have
+ * wake-up enabled. When system is suspended, only selected GPIO interrupts
+ * need to have wake-up enabled.
+ * @param irq interrupt source number
+ * @param enable enable as wake-up if equal to non-zero
+ * @return This function returns 0 on success.
+ */
+static int mxs_gpio_set_wake_irq(u32 irq, u32 enable)
+{
+ u32 gpio = irq_to_gpio(irq);
+ u32 gpio_idx = gpio & 0x1f;
+ struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
+
+ if (enable) {
+ if (port->irq_high && (gpio_idx >= 16))
+ enable_irq_wake(port->irq_high);
+ else
+ enable_irq_wake(port->irq);
+ } else {
+ if (port->irq_high && (gpio_idx >= 16))
+ disable_irq_wake(port->irq_high);
+ else
+ disable_irq_wake(port->irq);
+ }
+
+ return 0;
+}
+
+static struct irq_chip gpio_irq_chip = {
+ .ack = mxs_gpio_ack_irq,
+ .mask = mxs_gpio_mask_irq,
+ .unmask = mxs_gpio_unmask_irq,
+ .set_type = mxs_gpio_set_irq_type,
+ .set_wake = mxs_gpio_set_wake_irq,
+};
+
+static void mxs_set_gpio_direction(struct gpio_chip *chip, unsigned offset,
+ int dir)
+{
+ struct mxs_gpio_port *port =
+ container_of(chip, struct mxs_gpio_port, chip);
+ void __iomem *pin_addr = port->base + PINCTRL_DOE(port->id);
+
+ if (dir)
+ __mxs_setl(1 << offset, pin_addr);
+ else
+ __mxs_clrl(1 << offset, pin_addr);
+}
+
+static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct mxs_gpio_port *port =
+ container_of(chip, struct mxs_gpio_port, chip);
+
+ return (__raw_readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
+}
+
+static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct mxs_gpio_port *port =
+ container_of(chip, struct mxs_gpio_port, chip);
+ void __iomem *pin_addr = port->base + PINCTRL_DOUT(port->id);
+
+ if (value)
+ __mxs_setl(1 << offset, pin_addr);
+ else
+ __mxs_clrl(1 << offset, pin_addr);
+}
+
+static int mxs_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ struct mxs_gpio_port *port =
+ container_of(chip, struct mxs_gpio_port, chip);
+
+ return port->virtual_irq_start + offset;
+}
+
+static int mxs_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ mxs_set_gpio_direction(chip, offset, 0);
+ return 0;
+}
+
+static int mxs_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ mxs_gpio_set(chip, offset, value);
+ mxs_set_gpio_direction(chip, offset, 1);
+ return 0;
+}
+
+int __init mxs_gpio_init(struct mxs_gpio_port *port, int cnt)
+{
+ int i, j;
+
+ /* save for local usage */
+ mxs_gpio_ports = port;
+ gpio_table_size = cnt;
+
+ pr_info("MXS GPIO hardware\n");
+
+ for (i = 0; i < cnt; i++) {
+ /* disable the interrupt and clear the status */
+ __raw_writel(0, port[i].base + PINCTRL_PIN2IRQ(i));
+ __raw_writel(0, port[i].base + PINCTRL_IRQEN(i));
+
+ /* clear address has to be used to clear IRQSTAT bits */
+ __mxs_clrl(~0U, port[i].base + PINCTRL_IRQSTAT(i));
+
+ for (j = port[i].virtual_irq_start;
+ j < port[i].virtual_irq_start + 32; j++) {
+ set_irq_chip(j, &gpio_irq_chip);
+ set_irq_handler(j, handle_level_irq);
+ set_irq_flags(j, IRQF_VALID);
+ }
+
+ /* setup one handler for each entry */
+ set_irq_chained_handler(port[i].irq, mxs_gpio_irq_handler);
+ set_irq_data(port[i].irq, &port[i]);
+
+ /* register gpio chip */
+ port[i].chip.direction_input = mxs_gpio_direction_input;
+ port[i].chip.direction_output = mxs_gpio_direction_output;
+ port[i].chip.get = mxs_gpio_get;
+ port[i].chip.set = mxs_gpio_set;
+ port[i].chip.to_irq = mxs_gpio_to_irq;
+ port[i].chip.base = i * 32;
+ port[i].chip.ngpio = 32;
+
+ /* its a serious configuration bug when it fails */
+ BUG_ON(gpiochip_add(&port[i].chip) < 0);
+ }
+
+ return 0;
+}
+
+#define DEFINE_MXS_GPIO_PORT(soc, _id) \
+ { \
+ .chip.label = "gpio-" #_id, \
+ .id = _id, \
+ .irq = soc ## _INT_GPIO ## _id, \
+ .base = soc ## _IO_ADDRESS( \
+ soc ## _PINCTRL ## _BASE_ADDR), \
+ .virtual_irq_start = MXS_GPIO_IRQ_START + (_id) * 32, \
+ }
+
+#define DEFINE_REGISTER_FUNCTION(prefix) \
+int __init prefix ## _register_gpios(void) \
+{ \
+ return mxs_gpio_init(prefix ## _gpio_ports, \
+ ARRAY_SIZE(prefix ## _gpio_ports)); \
+}
+
+#ifdef CONFIG_SOC_IMX23
+static struct mxs_gpio_port mx23_gpio_ports[] = {
+ DEFINE_MXS_GPIO_PORT(MX23, 0),
+ DEFINE_MXS_GPIO_PORT(MX23, 1),
+ DEFINE_MXS_GPIO_PORT(MX23, 2),
+};
+DEFINE_REGISTER_FUNCTION(mx23)
+#endif
+
+#ifdef CONFIG_SOC_IMX28
+static struct mxs_gpio_port mx28_gpio_ports[] = {
+ DEFINE_MXS_GPIO_PORT(MX28, 0),
+ DEFINE_MXS_GPIO_PORT(MX28, 1),
+ DEFINE_MXS_GPIO_PORT(MX28, 2),
+ DEFINE_MXS_GPIO_PORT(MX28, 3),
+ DEFINE_MXS_GPIO_PORT(MX28, 4),
+};
+DEFINE_REGISTER_FUNCTION(mx28)
+#endif
diff --git a/arch/arm/mach-mxs/gpio.h b/arch/arm/mach-mxs/gpio.h
new file mode 100644
index 0000000..005bb06
--- /dev/null
+++ b/arch/arm/mach-mxs/gpio.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Juergen Beisert, kernel at pengutronix.de
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#ifndef __MXS_GPIO_H__
+#define __MXS_GPIO_H__
+
+struct mxs_gpio_port {
+ void __iomem *base;
+ int id;
+ int irq;
+ int irq_high;
+ int virtual_irq_start;
+ struct gpio_chip chip;
+};
+
+int mxs_gpio_init(struct mxs_gpio_port*, int);
+
+#endif /* __MXS_GPIO_H__ */
diff --git a/arch/arm/mach-mxs/include/mach/gpio.h b/arch/arm/mach-mxs/include/mach/gpio.h
new file mode 100644
index 0000000..828cccc
--- /dev/null
+++ b/arch/arm/mach-mxs/include/mach/gpio.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Juergen Beisert, kernel at pengutronix.de
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#ifndef __MACH_MXS_GPIO_H__
+#define __MACH_MXS_GPIO_H__
+
+#include <asm-generic/gpio.h>
+
+#define MXS_GPIO_NR(bank, nr) ((bank) * 32 + (nr))
+
+/* use gpiolib dispatchers */
+#define gpio_get_value __gpio_get_value
+#define gpio_set_value __gpio_set_value
+#define gpio_cansleep __gpio_cansleep
+#define gpio_to_irq __gpio_to_irq
+
+#define irq_to_gpio(irq) ((irq) - MXS_GPIO_IRQ_START)
+
+#endif /* __MACH_MXS_GPIO_H__ */
--
1.7.1
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