diff options
author | Shawn Guo <shawn.guo@linaro.org> | 2011-06-06 00:07:54 +0800 |
---|---|---|
committer | Grant Likely <grant.likely@secretlab.ca> | 2011-06-06 10:01:19 -0600 |
commit | d37a65bb4663bde7cf3dbc51aec7f264fa4d0ebf (patch) | |
tree | 5cea55304a0c2863273299209c7edd6518617377 /drivers/gpio/gpio-mxc.c | |
parent | 8d7cf8370d5fb75a3265408dceb1d6173eebfafd (diff) | |
download | linux-d37a65bb4663bde7cf3dbc51aec7f264fa4d0ebf.tar.bz2 |
gpio/mxc: Move Freescale MXC gpio driver to drivers/gpio
GPIO drivers are getting moved to drivers/gpio for cleanup and
consolidation. This patch moves the plat-mxc driver. Follow up
patches will clean it up and make it a fine upstanding gpio driver.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'drivers/gpio/gpio-mxc.c')
-rw-r--r-- | drivers/gpio/gpio-mxc.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c new file mode 100644 index 000000000000..6cd6d7f686f6 --- /dev/null +++ b/drivers/gpio/gpio-mxc.c @@ -0,0 +1,361 @@ +/* + * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> + * Copyright 2008 Juergen Beisert, kernel@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/hardware.h> +#include <asm-generic/bug.h> + +static struct mxc_gpio_port *mxc_gpio_ports; +static int gpio_table_size; + +#define cpu_is_mx1_mx2() (cpu_is_mx1() || cpu_is_mx2()) + +#define GPIO_DR (cpu_is_mx1_mx2() ? 0x1c : 0x00) +#define GPIO_GDIR (cpu_is_mx1_mx2() ? 0x00 : 0x04) +#define GPIO_PSR (cpu_is_mx1_mx2() ? 0x24 : 0x08) +#define GPIO_ICR1 (cpu_is_mx1_mx2() ? 0x28 : 0x0C) +#define GPIO_ICR2 (cpu_is_mx1_mx2() ? 0x2C : 0x10) +#define GPIO_IMR (cpu_is_mx1_mx2() ? 0x30 : 0x14) +#define GPIO_ISR (cpu_is_mx1_mx2() ? 0x34 : 0x18) + +#define GPIO_INT_LOW_LEV (cpu_is_mx1_mx2() ? 0x3 : 0x0) +#define GPIO_INT_HIGH_LEV (cpu_is_mx1_mx2() ? 0x2 : 0x1) +#define GPIO_INT_RISE_EDGE (cpu_is_mx1_mx2() ? 0x0 : 0x2) +#define GPIO_INT_FALL_EDGE (cpu_is_mx1_mx2() ? 0x1 : 0x3) +#define GPIO_INT_NONE 0x4 + +/* 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(struct irq_data *d) +{ + u32 gpio = irq_to_gpio(d->irq); + _clear_gpio_irqstatus(&mxc_gpio_ports[gpio / 32], gpio & 0x1f); +} + +static void gpio_mask_irq(struct irq_data *d) +{ + u32 gpio = irq_to_gpio(d->irq); + _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 0); +} + +static void gpio_unmask_irq(struct irq_data *d) +{ + u32 gpio = irq_to_gpio(d->irq); + _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 1); +} + +static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset); + +static int gpio_set_irq_type(struct irq_data *d, u32 type) +{ + u32 gpio = irq_to_gpio(d->irq); + struct mxc_gpio_port *port = &mxc_gpio_ports[gpio / 32]; + u32 bit, val; + int edge; + void __iomem *reg = port->base; + + port->both_edges &= ~(1 << (gpio & 31)); + 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_EDGE_BOTH: + val = mxc_gpio_get(&port->chip, gpio & 31); + if (val) { + edge = GPIO_INT_LOW_LEV; + pr_debug("mxc: set GPIO %d to low trigger\n", gpio); + } else { + edge = GPIO_INT_HIGH_LEV; + pr_debug("mxc: set GPIO %d to high trigger\n", gpio); + } + port->both_edges |= 1 << (gpio & 31); + 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; + } + + 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; +} + +static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) +{ + void __iomem *reg = port->base; + u32 bit, val; + int edge; + + reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ + bit = gpio & 0xf; + val = __raw_readl(reg); + edge = (val >> (bit << 1)) & 3; + val &= ~(0x3 << (bit << 1)); + if (edge == GPIO_INT_HIGH_LEV) { + edge = GPIO_INT_LOW_LEV; + pr_debug("mxc: switch GPIO %d to low trigger\n", gpio); + } else if (edge == GPIO_INT_LOW_LEV) { + edge = GPIO_INT_HIGH_LEV; + pr_debug("mxc: switch GPIO %d to high trigger\n", gpio); + } else { + pr_err("mxc: invalid configuration for GPIO %d: %x\n", + gpio, edge); + return; + } + __raw_writel(val | (edge << (bit << 1)), reg); +} + +/* handle 32 interrupts in one status register */ +static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat) +{ + u32 gpio_irq_no_base = port->virtual_irq_start; + + while (irq_stat != 0) { + int irqoffset = fls(irq_stat) - 1; + + if (port->both_edges & (1 << irqoffset)) + mxc_flip_edge(port, irqoffset); + + generic_handle_irq(gpio_irq_no_base + irqoffset); + + irq_stat &= ~(1 << irqoffset); + } +} + +/* MX1 and 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 = irq_get_handler_data(irq); + + irq_stat = __raw_readl(port->base + GPIO_ISR) & + __raw_readl(port->base + GPIO_IMR); + + mxc_gpio_irq_handler(port, irq_stat); +} + +/* 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 = irq_get_handler_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); + } +} + +/* + * 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 gpio_set_wake_irq(struct irq_data *d, u32 enable) +{ + u32 gpio = irq_to_gpio(d->irq); + u32 gpio_idx = gpio & 0x1F; + struct mxc_gpio_port *port = &mxc_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 = { + .name = "GPIO", + .irq_ack = gpio_ack_irq, + .irq_mask = gpio_mask_irq, + .irq_unmask = gpio_unmask_irq, + .irq_set_type = gpio_set_irq_type, + .irq_set_wake = gpio_set_wake_irq, +}; + +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; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + l = __raw_readl(port->base + GPIO_GDIR); + if (dir) + l |= 1 << offset; + else + l &= ~(1 << offset); + __raw_writel(l, port->base + GPIO_GDIR); + spin_unlock_irqrestore(&port->lock, flags); +} + +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; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + l = (__raw_readl(reg) & (~(1 << offset))) | (!!value << offset); + __raw_writel(l, reg); + spin_unlock_irqrestore(&port->lock, flags); +} + +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_PSR) >> 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) +{ + mxc_gpio_set(chip, offset, value); + _set_gpio_direction(chip, offset, 1); + return 0; +} + +/* + * This lock class tells lockdep that GPIO irqs are in a different + * category than their parents, so it won't report false recursion. + */ +static struct lock_class_key gpio_lock_class; + +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++) { + irq_set_lockdep_class(j, &gpio_lock_class); + irq_set_chip_and_handler(j, &gpio_irq_chip, + handle_level_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; + + spin_lock_init(&port[i].lock); + + /* its a serious configuration bug when it fails */ + BUG_ON( gpiochip_add(&port[i].chip) < 0 ); + + if (cpu_is_mx1() || cpu_is_mx3() || cpu_is_mx25() || cpu_is_mx51()) { + /* setup one handler for each entry */ + irq_set_chained_handler(port[i].irq, + mx3_gpio_irq_handler); + irq_set_handler_data(port[i].irq, &port[i]); + if (port[i].irq_high) { + /* setup handler for GPIO 16 to 31 */ + irq_set_chained_handler(port[i].irq_high, + mx3_gpio_irq_handler); + irq_set_handler_data(port[i].irq_high, + &port[i]); + } + } + } + + if (cpu_is_mx2()) { + /* setup one handler for all GPIO interrupts */ + irq_set_chained_handler(port[0].irq, mx2_gpio_irq_handler); + irq_set_handler_data(port[0].irq, port); + } + + return 0; +} |