/* * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> * Copyright 2008 Juergen Beisert, kernel@pengutronix.de * * Based on code from Freescale, * Copyright 2004-2006 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/io.h> #include <linux/irq.h> #include <linux/gpio.h> #include <asm/hardware.h> #include <asm-generic/bug.h> static struct mxc_gpio_port *mxc_gpio_ports; static int gpio_table_size; /* Note: This driver assumes 32 GPIOs are handled in one register */ static void _clear_gpio_irqstatus(struct mxc_gpio_port *port, u32 index) { __raw_writel(1 << index, port->base + GPIO_ISR); } static void _set_gpio_irqenable(struct mxc_gpio_port *port, u32 index, int enable) { u32 l; l = __raw_readl(port->base + GPIO_IMR); l = (l & (~(1 << index))) | (!!enable << index); __raw_writel(l, port->base + GPIO_IMR); } static void gpio_ack_irq(u32 irq) { u32 gpio = irq_to_gpio(irq); _clear_gpio_irqstatus(&mxc_gpio_ports[gpio / 32], gpio & 0x1f); } static void gpio_mask_irq(u32 irq) { u32 gpio = irq_to_gpio(irq); _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 0); } static void gpio_unmask_irq(u32 irq) { u32 gpio = irq_to_gpio(irq); _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 1); } static int gpio_set_irq_type(u32 irq, u32 type) { u32 gpio = irq_to_gpio(irq); struct mxc_gpio_port *port = &mxc_gpio_ports[gpio / 32]; u32 bit, val; int edge; void __iomem *reg = port->base; 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: /* this includes IRQ_TYPE_EDGE_BOTH */ return -EINVAL; } reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ bit = gpio & 0xf; val = __raw_readl(reg) & ~(0x3 << (bit << 1)); __raw_writel(val | (edge << (bit << 1)), reg); _clear_gpio_irqstatus(port, gpio & 0x1f); return 0; } /* handle n interrupts in one status register */ static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat) { u32 gpio_irq_no; gpio_irq_no = port->virtual_irq_start; for (; irq_stat != 0; irq_stat >>= 1, gpio_irq_no++) { if ((irq_stat & 1) == 0) continue; BUG_ON(!(irq_desc[gpio_irq_no].handle_irq)); irq_desc[gpio_irq_no].handle_irq(gpio_irq_no, &irq_desc[gpio_irq_no]); } } #ifdef CONFIG_ARCH_MX3 /* MX3 has one interrupt *per* gpio port */ static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc) { u32 irq_stat; struct mxc_gpio_port *port = (struct mxc_gpio_port *)get_irq_data(irq); irq_stat = __raw_readl(port->base + GPIO_ISR) & __raw_readl(port->base + GPIO_IMR); BUG_ON(!irq_stat); mxc_gpio_irq_handler(port, irq_stat); } #endif #ifdef CONFIG_ARCH_MX2 /* MX2 has one interrupt *for all* gpio ports */ static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc) { int i; u32 irq_msk, irq_stat; struct mxc_gpio_port *port = (struct mxc_gpio_port *)get_irq_data(irq); /* walk through all interrupt status registers */ for (i = 0; i < gpio_table_size; i++) { irq_msk = __raw_readl(port[i].base + GPIO_IMR); if (!irq_msk) continue; irq_stat = __raw_readl(port[i].base + GPIO_ISR) & irq_msk; if (irq_stat) mxc_gpio_irq_handler(&port[i], irq_stat); } } #endif static struct irq_chip gpio_irq_chip = { .ack = gpio_ack_irq, .mask = gpio_mask_irq, .unmask = gpio_unmask_irq, .set_type = gpio_set_irq_type, }; static void _set_gpio_direction(struct gpio_chip *chip, unsigned offset, int dir) { struct mxc_gpio_port *port = container_of(chip, struct mxc_gpio_port, chip); u32 l; l = __raw_readl(port->base + GPIO_GDIR); if (dir) l |= 1 << offset; else l &= ~(1 << offset); __raw_writel(l, port->base + GPIO_GDIR); } static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { struct mxc_gpio_port *port = container_of(chip, struct mxc_gpio_port, chip); void __iomem *reg = port->base + GPIO_DR; u32 l; l = (__raw_readl(reg) & (~(1 << offset))) | (value << offset); __raw_writel(l, reg); } static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset) { struct mxc_gpio_port *port = container_of(chip, struct mxc_gpio_port, chip); return (__raw_readl(port->base + GPIO_DR) >> offset) & 1; } static int mxc_gpio_direction_input(struct gpio_chip *chip, unsigned offset) { _set_gpio_direction(chip, offset, 0); return 0; } static int mxc_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value) { _set_gpio_direction(chip, offset, 1); mxc_gpio_set(chip, offset, value); return 0; } int __init mxc_gpio_init(struct mxc_gpio_port *port, int cnt) { int i, j; /* save for local usage */ mxc_gpio_ports = port; gpio_table_size = cnt; printk(KERN_INFO "MXC GPIO hardware\n"); for (i = 0; i < cnt; i++) { /* disable the interrupt and clear the status */ __raw_writel(0, port[i].base + GPIO_IMR); __raw_writel(~0, port[i].base + GPIO_ISR); 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_edge_irq); set_irq_flags(j, IRQF_VALID); } /* register gpio chip */ port[i].chip.direction_input = mxc_gpio_direction_input; port[i].chip.direction_output = mxc_gpio_direction_output; port[i].chip.get = mxc_gpio_get; port[i].chip.set = mxc_gpio_set; 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 ); #ifdef CONFIG_ARCH_MX3 /* setup one handler for each entry */ set_irq_chained_handler(port[i].irq, mx3_gpio_irq_handler); set_irq_data(port[i].irq, &port[i]); #endif } #ifdef CONFIG_ARCH_MX2 /* setup one handler for all GPIO interrupts */ set_irq_chained_handler(port[0].irq, mx2_gpio_irq_handler); set_irq_data(port[0].irq, port); #endif return 0; }