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authorEric Miao <eric.miao@marvell.com>2009-01-20 12:09:06 +0800
committerEric Miao <eric.miao@marvell.com>2009-03-23 10:11:33 +0800
commit38f539a608c9a3b40b30f1892bd5f9a38f4e5ffe (patch)
treefeb9c3ee23fe75151f73e8916c1afeb7c562e0dd /arch/arm/plat-pxa
parentbd5ce4332328c1fe473690a86b2e6a4157be038f (diff)
[ARM] pxa: move common GPIO handling code into plat-pxa
1. add common GPIO handling code into [arch/arm/plat-pxa] 2. common code in <mach/gpio.h> moved into <plat/gpio.h>, new processors should implement its own <mach/gpio.h>, provide the following required definitions and '#include <plat/gpio.h>' in the end: - GPIO_REGS_VIRT for mapped virtual address of the GPIO registers' physical I/O memory - macros of GPLR(), GPSR(), GPDR() for constant optimization for functions gpio_{set,get}_value() (so that bit-bang code can still have tolerable performance) - NR_BUILTIN_GPIO for the number of onchip GPIO - definitions of __gpio_is_inverted() and __gpio_is_occupied(), they can be either macros or inlined functions Signed-off-by: Eric Miao <eric.miao@marvell.com>
Diffstat (limited to 'arch/arm/plat-pxa')
-rw-r--r--arch/arm/plat-pxa/Makefile1
-rw-r--r--arch/arm/plat-pxa/gpio.c337
-rw-r--r--arch/arm/plat-pxa/include/plat/gpio.h62
3 files changed, 400 insertions, 0 deletions
diff --git a/arch/arm/plat-pxa/Makefile b/arch/arm/plat-pxa/Makefile
index dcc3ceaf717..b837df44048 100644
--- a/arch/arm/plat-pxa/Makefile
+++ b/arch/arm/plat-pxa/Makefile
@@ -4,3 +4,4 @@
obj-y := dma.o
+obj-$(CONFIG_GENERIC_GPIO) += gpio.o
diff --git a/arch/arm/plat-pxa/gpio.c b/arch/arm/plat-pxa/gpio.c
new file mode 100644
index 00000000000..af819bf21b6
--- /dev/null
+++ b/arch/arm/plat-pxa/gpio.c
@@ -0,0 +1,337 @@
+/*
+ * linux/arch/arm/plat-pxa/gpio.c
+ *
+ * Generic PXA GPIO handling
+ *
+ * Author: Nicolas Pitre
+ * Created: Jun 15, 2001
+ * Copyright: MontaVista Software Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/sysdev.h>
+#include <linux/bootmem.h>
+
+#include <mach/gpio.h>
+
+int pxa_last_gpio;
+
+struct pxa_gpio_chip {
+ struct gpio_chip chip;
+ void __iomem *regbase;
+ char label[10];
+
+ unsigned long irq_mask;
+ unsigned long irq_edge_rise;
+ unsigned long irq_edge_fall;
+
+#ifdef CONFIG_PM
+ unsigned long saved_gplr;
+ unsigned long saved_gpdr;
+ unsigned long saved_grer;
+ unsigned long saved_gfer;
+#endif
+};
+
+static DEFINE_SPINLOCK(gpio_lock);
+static struct pxa_gpio_chip *pxa_gpio_chips;
+
+#define for_each_gpio_chip(i, c) \
+ for (i = 0, c = &pxa_gpio_chips[0]; i <= pxa_last_gpio; i += 32, c++)
+
+static inline void __iomem *gpio_chip_base(struct gpio_chip *c)
+{
+ return container_of(c, struct pxa_gpio_chip, chip)->regbase;
+}
+
+static inline struct pxa_gpio_chip *gpio_to_chip(unsigned gpio)
+{
+ return &pxa_gpio_chips[gpio_to_bank(gpio)];
+}
+
+static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ void __iomem *base = gpio_chip_base(chip);
+ uint32_t value, mask = 1 << offset;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ value = __raw_readl(base + GPDR_OFFSET);
+ if (__gpio_is_inverted(chip->base + offset))
+ value |= mask;
+ else
+ value &= ~mask;
+ __raw_writel(value, base + GPDR_OFFSET);
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ return 0;
+}
+
+static int pxa_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ void __iomem *base = gpio_chip_base(chip);
+ uint32_t tmp, mask = 1 << offset;
+ unsigned long flags;
+
+ __raw_writel(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ tmp = __raw_readl(base + GPDR_OFFSET);
+ if (__gpio_is_inverted(chip->base + offset))
+ tmp &= ~mask;
+ else
+ tmp |= mask;
+ __raw_writel(tmp, base + GPDR_OFFSET);
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ return 0;
+}
+
+static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ return __raw_readl(gpio_chip_base(chip) + GPLR_OFFSET) & (1 << offset);
+}
+
+static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ __raw_writel(1 << offset, gpio_chip_base(chip) +
+ (value ? GPSR_OFFSET : GPCR_OFFSET));
+}
+
+static int __init pxa_init_gpio_chip(int gpio_end)
+{
+ int i, gpio, nbanks = gpio_to_bank(gpio_end) + 1;
+ struct pxa_gpio_chip *chips;
+
+ /* this is early, we have to use bootmem allocator, and we really
+ * want this to be allocated dynamically for different 'gpio_end'
+ */
+ chips = alloc_bootmem_low(nbanks * sizeof(struct pxa_gpio_chip));
+ if (chips == NULL) {
+ pr_err("%s: failed to allocate GPIO chips\n", __func__);
+ return -ENOMEM;
+ }
+
+ for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
+ struct gpio_chip *c = &chips[i].chip;
+
+ sprintf(chips[i].label, "gpio-%d", i);
+ chips[i].regbase = (void __iomem *)GPIO_BANK(i);
+
+ c->base = gpio;
+ c->label = chips[i].label;
+
+ c->direction_input = pxa_gpio_direction_input;
+ c->direction_output = pxa_gpio_direction_output;
+ c->get = pxa_gpio_get;
+ c->set = pxa_gpio_set;
+
+ /* number of GPIOs on last bank may be less than 32 */
+ c->ngpio = (gpio + 31 > gpio_end) ? (gpio_end - gpio + 1) : 32;
+ gpiochip_add(c);
+ }
+ pxa_gpio_chips = chips;
+ return 0;
+}
+
+static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
+{
+ struct pxa_gpio_chip *c;
+ int gpio = irq_to_gpio(irq);
+ unsigned long gpdr, mask = GPIO_bit(gpio);
+
+ c = gpio_to_chip(gpio);
+
+ if (type == IRQ_TYPE_PROBE) {
+ /* Don't mess with enabled GPIOs using preconfigured edges or
+ * GPIOs set to alternate function or to output during probe
+ */
+ if ((c->irq_edge_rise | c->irq_edge_fall) & GPIO_bit(gpio))
+ return 0;
+
+ if (__gpio_is_occupied(gpio))
+ return 0;
+
+ type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+ }
+
+ gpdr = __raw_readl(c->regbase + GPDR_OFFSET);
+
+ if (__gpio_is_inverted(gpio))
+ __raw_writel(gpdr | mask, c->regbase + GPDR_OFFSET);
+ else
+ __raw_writel(gpdr & ~mask, c->regbase + GPDR_OFFSET);
+
+ if (type & IRQ_TYPE_EDGE_RISING)
+ c->irq_edge_rise |= mask;
+ else
+ c->irq_edge_rise &= ~mask;
+
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ c->irq_edge_fall |= mask;
+ else
+ c->irq_edge_fall &= ~mask;
+
+ __raw_writel(c->irq_edge_rise & c->irq_mask, c->regbase + GRER_OFFSET);
+ __raw_writel(c->irq_edge_fall & c->irq_mask, c->regbase + GFER_OFFSET);
+
+ pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
+ ((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
+ ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
+ return 0;
+}
+
+static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
+{
+ struct pxa_gpio_chip *c;
+ int loop, gpio, gpio_base, n;
+ unsigned long gedr;
+
+ do {
+ loop = 0;
+ for_each_gpio_chip(gpio, c) {
+ gpio_base = c->chip.base;
+
+ gedr = __raw_readl(c->regbase + GEDR_OFFSET);
+ gedr = gedr & c->irq_mask;
+ __raw_writel(gedr, c->regbase + GEDR_OFFSET);
+
+ n = find_first_bit(&gedr, BITS_PER_LONG);
+ while (n < BITS_PER_LONG) {
+ loop = 1;
+
+ generic_handle_irq(gpio_to_irq(gpio_base + n));
+ n = find_next_bit(&gedr, BITS_PER_LONG, n + 1);
+ }
+ }
+ } while (loop);
+}
+
+static void pxa_ack_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq_to_gpio(irq);
+ struct pxa_gpio_chip *c = gpio_to_chip(gpio);
+
+ __raw_writel(GPIO_bit(gpio), c->regbase + GEDR_OFFSET);
+}
+
+static void pxa_mask_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq_to_gpio(irq);
+ struct pxa_gpio_chip *c = gpio_to_chip(gpio);
+ uint32_t grer, gfer;
+
+ c->irq_mask &= ~GPIO_bit(gpio);
+
+ grer = __raw_readl(c->regbase + GRER_OFFSET) & ~GPIO_bit(gpio);
+ gfer = __raw_readl(c->regbase + GFER_OFFSET) & ~GPIO_bit(gpio);
+ __raw_writel(grer, c->regbase + GRER_OFFSET);
+ __raw_writel(gfer, c->regbase + GFER_OFFSET);
+}
+
+static void pxa_unmask_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq_to_gpio(irq);
+ struct pxa_gpio_chip *c = gpio_to_chip(gpio);
+
+ c->irq_mask |= GPIO_bit(gpio);
+ __raw_writel(c->irq_edge_rise & c->irq_mask, c->regbase + GRER_OFFSET);
+ __raw_writel(c->irq_edge_fall & c->irq_mask, c->regbase + GFER_OFFSET);
+}
+
+static struct irq_chip pxa_muxed_gpio_chip = {
+ .name = "GPIO",
+ .ack = pxa_ack_muxed_gpio,
+ .mask = pxa_mask_muxed_gpio,
+ .unmask = pxa_unmask_muxed_gpio,
+ .set_type = pxa_gpio_irq_type,
+};
+
+void __init pxa_init_gpio(int mux_irq, int start, int end, set_wake_t fn)
+{
+ struct pxa_gpio_chip *c;
+ int gpio, irq;
+
+ pxa_last_gpio = end;
+
+ /* Initialize GPIO chips */
+ pxa_init_gpio_chip(end);
+
+ /* clear all GPIO edge detects */
+ for_each_gpio_chip(gpio, c) {
+ __raw_writel(0, c->regbase + GFER_OFFSET);
+ __raw_writel(0, c->regbase + GRER_OFFSET);
+ __raw_writel(~0,c->regbase + GEDR_OFFSET);
+ }
+
+ for (irq = gpio_to_irq(start); irq <= gpio_to_irq(end); irq++) {
+ set_irq_chip(irq, &pxa_muxed_gpio_chip);
+ set_irq_handler(irq, handle_edge_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ /* Install handler for GPIO>=2 edge detect interrupts */
+ set_irq_chained_handler(mux_irq, pxa_gpio_demux_handler);
+ pxa_muxed_gpio_chip.set_wake = fn;
+}
+
+#ifdef CONFIG_PM
+static int pxa_gpio_suspend(struct sys_device *dev, pm_message_t state)
+{
+ struct pxa_gpio_chip *c;
+ int gpio;
+
+ for_each_gpio_chip(gpio, c) {
+ c->saved_gplr = __raw_readl(c->regbase + GPLR_OFFSET);
+ c->saved_gpdr = __raw_readl(c->regbase + GPDR_OFFSET);
+ c->saved_grer = __raw_readl(c->regbase + GRER_OFFSET);
+ c->saved_gfer = __raw_readl(c->regbase + GFER_OFFSET);
+
+ /* Clear GPIO transition detect bits */
+ __raw_writel(0xffffffff, c->regbase + GEDR_OFFSET);
+ }
+ return 0;
+}
+
+static int pxa_gpio_resume(struct sys_device *dev)
+{
+ struct pxa_gpio_chip *c;
+ int gpio;
+
+ for_each_gpio_chip(gpio, c) {
+ /* restore level with set/clear */
+ __raw_writel( c->saved_gplr, c->regbase + GPSR_OFFSET);
+ __raw_writel(~c->saved_gplr, c->regbase + GPCR_OFFSET);
+
+ __raw_writel(c->saved_grer, c->regbase + GRER_OFFSET);
+ __raw_writel(c->saved_gfer, c->regbase + GFER_OFFSET);
+ __raw_writel(c->saved_gpdr, c->regbase + GPDR_OFFSET);
+ }
+ return 0;
+}
+#else
+#define pxa_gpio_suspend NULL
+#define pxa_gpio_resume NULL
+#endif
+
+struct sysdev_class pxa_gpio_sysclass = {
+ .name = "gpio",
+ .suspend = pxa_gpio_suspend,
+ .resume = pxa_gpio_resume,
+};
+
+static int __init pxa_gpio_init(void)
+{
+ return sysdev_class_register(&pxa_gpio_sysclass);
+}
+
+core_initcall(pxa_gpio_init);
diff --git a/arch/arm/plat-pxa/include/plat/gpio.h b/arch/arm/plat-pxa/include/plat/gpio.h
new file mode 100644
index 00000000000..44248cb926a
--- /dev/null
+++ b/arch/arm/plat-pxa/include/plat/gpio.h
@@ -0,0 +1,62 @@
+#ifndef __PLAT_GPIO_H
+#define __PLAT_GPIO_H
+
+/*
+ * We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
+ * one set of registers. The register offsets are organized below:
+ *
+ * GPLR GPDR GPSR GPCR GRER GFER GEDR
+ * BANK 0 - 0x0000 0x000C 0x0018 0x0024 0x0030 0x003C 0x0048
+ * BANK 1 - 0x0004 0x0010 0x001C 0x0028 0x0034 0x0040 0x004C
+ * BANK 2 - 0x0008 0x0014 0x0020 0x002C 0x0038 0x0044 0x0050
+ *
+ * BANK 3 - 0x0100 0x010C 0x0118 0x0124 0x0130 0x013C 0x0148
+ * BANK 4 - 0x0104 0x0110 0x011C 0x0128 0x0134 0x0140 0x014C
+ * BANK 5 - 0x0108 0x0114 0x0120 0x012C 0x0138 0x0144 0x0150
+ *
+ * NOTE:
+ * BANK 3 is only available on PXA27x and later processors.
+ * BANK 4 and 5 are only available on PXA935
+ */
+
+#define GPIO_BANK(n) (GPIO_REGS_VIRT + BANK_OFF(n))
+
+#define GPLR_OFFSET 0x00
+#define GPDR_OFFSET 0x0C
+#define GPSR_OFFSET 0x18
+#define GPCR_OFFSET 0x24
+#define GRER_OFFSET 0x30
+#define GFER_OFFSET 0x3C
+#define GEDR_OFFSET 0x48
+
+static inline int gpio_get_value(unsigned gpio)
+{
+ if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO))
+ return GPLR(gpio) & GPIO_bit(gpio);
+ else
+ return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+ if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO)) {
+ if (value)
+ GPSR(gpio) = GPIO_bit(gpio);
+ else
+ GPCR(gpio) = GPIO_bit(gpio);
+ } else
+ __gpio_set_value(gpio, value);
+}
+
+#define gpio_cansleep __gpio_cansleep
+
+/* NOTE: some PXAs have fewer on-chip GPIOs (like PXA255, with 85).
+ * Those cases currently cause holes in the GPIO number space, the
+ * actual number of the last GPIO is recorded by 'pxa_last_gpio'.
+ */
+extern int pxa_last_gpio;
+
+typedef int (*set_wake_t)(unsigned int irq, unsigned int on);
+
+extern void pxa_init_gpio(int mux_irq, int start, int end, set_wake_t fn);
+#endif /* __PLAT_GPIO_H */