+++ /dev/null
-/* Copyright (c) 2010-2011, Code Aurora Forum. 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 version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * 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.
- *
- */
-#define pr_fmt(fmt) "%s: " fmt, __func__
-
-#include <linux/bitmap.h>
-#include <linux/bitops.h>
-#include <linux/err.h>
-#include <linux/gpio.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/irqchip/chained_irq.h>
-#include <linux/irq.h>
-#include <linux/irqdomain.h>
-#include <linux/module.h>
-#include <linux/of_address.h>
-#include <linux/platform_device.h>
-#include <linux/spinlock.h>
-#include <linux/slab.h>
-
-#define MAX_NR_GPIO 300
-
-/* Bits of interest in the GPIO_IN_OUT register.
- */
-enum {
- GPIO_IN = 0,
- GPIO_OUT = 1
-};
-
-/* Bits of interest in the GPIO_INTR_STATUS register.
- */
-enum {
- INTR_STATUS = 0,
-};
-
-/* Bits of interest in the GPIO_CFG register.
- */
-enum {
- GPIO_OE = 9,
-};
-
-/* Bits of interest in the GPIO_INTR_CFG register.
- * When a GPIO triggers, two separate decisions are made, controlled
- * by two separate flags.
- *
- * - First, INTR_RAW_STATUS_EN controls whether or not the GPIO_INTR_STATUS
- * register for that GPIO will be updated to reflect the triggering of that
- * gpio. If this bit is 0, this register will not be updated.
- * - Second, INTR_ENABLE controls whether an interrupt is triggered.
- *
- * If INTR_ENABLE is set and INTR_RAW_STATUS_EN is NOT set, an interrupt
- * can be triggered but the status register will not reflect it.
- */
-enum {
- INTR_ENABLE = 0,
- INTR_POL_CTL = 1,
- INTR_DECT_CTL = 2,
- INTR_RAW_STATUS_EN = 3,
-};
-
-/* Codes of interest in GPIO_INTR_CFG_SU.
- */
-enum {
- TARGET_PROC_SCORPION = 4,
- TARGET_PROC_NONE = 7,
-};
-
-/**
- * struct msm_gpio_dev: the MSM8660 SoC GPIO device structure
- *
- * @enabled_irqs: a bitmap used to optimize the summary-irq handler. By
- * keeping track of which gpios are unmasked as irq sources, we avoid
- * having to do readl calls on hundreds of iomapped registers each time
- * the summary interrupt fires in order to locate the active interrupts.
- *
- * @wake_irqs: a bitmap for tracking which interrupt lines are enabled
- * as wakeup sources. When the device is suspended, interrupts which are
- * not wakeup sources are disabled.
- *
- * @dual_edge_irqs: a bitmap used to track which irqs are configured
- * as dual-edge, as this is not supported by the hardware and requires
- * some special handling in the driver.
- */
-struct msm_gpio_dev {
- struct gpio_chip gpio_chip;
- DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
- DECLARE_BITMAP(wake_irqs, MAX_NR_GPIO);
- DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
- struct irq_domain *domain;
- int summary_irq;
- void __iomem *msm_tlmm_base;
-};
-
-static struct msm_gpio_dev msm_gpio;
-
-#define GPIO_INTR_CFG_SU(gpio) (msm_gpio.msm_tlmm_base + 0x0400 + \
- (0x04 * (gpio)))
-#define GPIO_CONFIG(gpio) (msm_gpio.msm_tlmm_base + 0x1000 + \
- (0x10 * (gpio)))
-#define GPIO_IN_OUT(gpio) (msm_gpio.msm_tlmm_base + 0x1004 + \
- (0x10 * (gpio)))
-#define GPIO_INTR_CFG(gpio) (msm_gpio.msm_tlmm_base + 0x1008 + \
- (0x10 * (gpio)))
-#define GPIO_INTR_STATUS(gpio) (msm_gpio.msm_tlmm_base + 0x100c + \
- (0x10 * (gpio)))
-
-static DEFINE_SPINLOCK(tlmm_lock);
-
-static inline struct msm_gpio_dev *to_msm_gpio_dev(struct gpio_chip *chip)
-{
- return container_of(chip, struct msm_gpio_dev, gpio_chip);
-}
-
-static inline void set_gpio_bits(unsigned n, void __iomem *reg)
-{
- writel(readl(reg) | n, reg);
-}
-
-static inline void clear_gpio_bits(unsigned n, void __iomem *reg)
-{
- writel(readl(reg) & ~n, reg);
-}
-
-static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
-{
- return readl(GPIO_IN_OUT(offset)) & BIT(GPIO_IN);
-}
-
-static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
-{
- writel(val ? BIT(GPIO_OUT) : 0, GPIO_IN_OUT(offset));
-}
-
-static int msm_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
-{
- unsigned long irq_flags;
-
- spin_lock_irqsave(&tlmm_lock, irq_flags);
- clear_gpio_bits(BIT(GPIO_OE), GPIO_CONFIG(offset));
- spin_unlock_irqrestore(&tlmm_lock, irq_flags);
- return 0;
-}
-
-static int msm_gpio_direction_output(struct gpio_chip *chip,
- unsigned offset,
- int val)
-{
- unsigned long irq_flags;
-
- spin_lock_irqsave(&tlmm_lock, irq_flags);
- msm_gpio_set(chip, offset, val);
- set_gpio_bits(BIT(GPIO_OE), GPIO_CONFIG(offset));
- spin_unlock_irqrestore(&tlmm_lock, irq_flags);
- return 0;
-}
-
-static int msm_gpio_request(struct gpio_chip *chip, unsigned offset)
-{
- return 0;
-}
-
-static void msm_gpio_free(struct gpio_chip *chip, unsigned offset)
-{
- return;
-}
-
-static int msm_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
-{
- struct msm_gpio_dev *g_dev = to_msm_gpio_dev(chip);
- struct irq_domain *domain = g_dev->domain;
-
- return irq_create_mapping(domain, offset);
-}
-
-/* For dual-edge interrupts in software, since the hardware has no
- * such support:
- *
- * At appropriate moments, this function may be called to flip the polarity
- * settings of both-edge irq lines to try and catch the next edge.
- *
- * The attempt is considered successful if:
- * - the status bit goes high, indicating that an edge was caught, or
- * - the input value of the gpio doesn't change during the attempt.
- * If the value changes twice during the process, that would cause the first
- * test to fail but would force the second, as two opposite
- * transitions would cause a detection no matter the polarity setting.
- *
- * The do-loop tries to sledge-hammer closed the timing hole between
- * the initial value-read and the polarity-write - if the line value changes
- * during that window, an interrupt is lost, the new polarity setting is
- * incorrect, and the first success test will fail, causing a retry.
- *
- * Algorithm comes from Google's msmgpio driver, see mach-msm/gpio.c.
- */
-static void msm_gpio_update_dual_edge_pos(unsigned gpio)
-{
- int loop_limit = 100;
- unsigned val, val2, intstat;
-
- do {
- val = readl(GPIO_IN_OUT(gpio)) & BIT(GPIO_IN);
- if (val)
- clear_gpio_bits(BIT(INTR_POL_CTL), GPIO_INTR_CFG(gpio));
- else
- set_gpio_bits(BIT(INTR_POL_CTL), GPIO_INTR_CFG(gpio));
- val2 = readl(GPIO_IN_OUT(gpio)) & BIT(GPIO_IN);
- intstat = readl(GPIO_INTR_STATUS(gpio)) & BIT(INTR_STATUS);
- if (intstat || val == val2)
- return;
- } while (loop_limit-- > 0);
- pr_err("%s: dual-edge irq failed to stabilize, "
- "interrupts dropped. %#08x != %#08x\n",
- __func__, val, val2);
-}
-
-static void msm_gpio_irq_ack(struct irq_data *d)
-{
- int gpio = d->hwirq;
-
- writel(BIT(INTR_STATUS), GPIO_INTR_STATUS(gpio));
- if (test_bit(gpio, msm_gpio.dual_edge_irqs))
- msm_gpio_update_dual_edge_pos(gpio);
-}
-
-static void msm_gpio_irq_mask(struct irq_data *d)
-{
- unsigned long irq_flags;
- int gpio = d->hwirq;
-
- spin_lock_irqsave(&tlmm_lock, irq_flags);
- writel(TARGET_PROC_NONE, GPIO_INTR_CFG_SU(gpio));
- clear_gpio_bits(BIT(INTR_RAW_STATUS_EN) | BIT(INTR_ENABLE), GPIO_INTR_CFG(gpio));
- __clear_bit(gpio, msm_gpio.enabled_irqs);
- spin_unlock_irqrestore(&tlmm_lock, irq_flags);
-}
-
-static void msm_gpio_irq_unmask(struct irq_data *d)
-{
- unsigned long irq_flags;
- int gpio = d->hwirq;
-
- spin_lock_irqsave(&tlmm_lock, irq_flags);
- __set_bit(gpio, msm_gpio.enabled_irqs);
- set_gpio_bits(BIT(INTR_RAW_STATUS_EN) | BIT(INTR_ENABLE), GPIO_INTR_CFG(gpio));
- writel(TARGET_PROC_SCORPION, GPIO_INTR_CFG_SU(gpio));
- spin_unlock_irqrestore(&tlmm_lock, irq_flags);
-}
-
-static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int flow_type)
-{
- unsigned long irq_flags;
- int gpio = d->hwirq;
- uint32_t bits;
-
- spin_lock_irqsave(&tlmm_lock, irq_flags);
-
- bits = readl(GPIO_INTR_CFG(gpio));
-
- if (flow_type & IRQ_TYPE_EDGE_BOTH) {
- bits |= BIT(INTR_DECT_CTL);
- irq_set_handler_locked(d, handle_edge_irq);
- if ((flow_type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
- __set_bit(gpio, msm_gpio.dual_edge_irqs);
- else
- __clear_bit(gpio, msm_gpio.dual_edge_irqs);
- } else {
- bits &= ~BIT(INTR_DECT_CTL);
- irq_set_handler_locked(d, handle_level_irq);
- __clear_bit(gpio, msm_gpio.dual_edge_irqs);
- }
-
- if (flow_type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
- bits |= BIT(INTR_POL_CTL);
- else
- bits &= ~BIT(INTR_POL_CTL);
-
- writel(bits, GPIO_INTR_CFG(gpio));
-
- if ((flow_type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
- msm_gpio_update_dual_edge_pos(gpio);
-
- spin_unlock_irqrestore(&tlmm_lock, irq_flags);
-
- return 0;
-}
-
-/*
- * When the summary IRQ is raised, any number of GPIO lines may be high.
- * It is the job of the summary handler to find all those GPIO lines
- * which have been set as summary IRQ lines and which are triggered,
- * and to call their interrupt handlers.
- */
-static void msm_summary_irq_handler(struct irq_desc *desc)
-{
- unsigned long i;
- struct irq_chip *chip = irq_desc_get_chip(desc);
-
- chained_irq_enter(chip, desc);
-
- for_each_set_bit(i, msm_gpio.enabled_irqs, MAX_NR_GPIO) {
- if (readl(GPIO_INTR_STATUS(i)) & BIT(INTR_STATUS))
- generic_handle_irq(irq_find_mapping(msm_gpio.domain,
- i));
- }
-
- chained_irq_exit(chip, desc);
-}
-
-static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
-{
- int gpio = d->hwirq;
-
- if (on) {
- if (bitmap_empty(msm_gpio.wake_irqs, MAX_NR_GPIO))
- irq_set_irq_wake(msm_gpio.summary_irq, 1);
- set_bit(gpio, msm_gpio.wake_irqs);
- } else {
- clear_bit(gpio, msm_gpio.wake_irqs);
- if (bitmap_empty(msm_gpio.wake_irqs, MAX_NR_GPIO))
- irq_set_irq_wake(msm_gpio.summary_irq, 0);
- }
-
- return 0;
-}
-
-static struct irq_chip msm_gpio_irq_chip = {
- .name = "msmgpio",
- .irq_mask = msm_gpio_irq_mask,
- .irq_unmask = msm_gpio_irq_unmask,
- .irq_ack = msm_gpio_irq_ack,
- .irq_set_type = msm_gpio_irq_set_type,
- .irq_set_wake = msm_gpio_irq_set_wake,
-};
-
-static struct lock_class_key msm_gpio_lock_class;
-
-static int msm_gpio_irq_domain_map(struct irq_domain *d, unsigned int irq,
- irq_hw_number_t hwirq)
-{
- irq_set_lockdep_class(irq, &msm_gpio_lock_class);
- irq_set_chip_and_handler(irq, &msm_gpio_irq_chip,
- handle_level_irq);
-
- return 0;
-}
-
-static const struct irq_domain_ops msm_gpio_irq_domain_ops = {
- .xlate = irq_domain_xlate_twocell,
- .map = msm_gpio_irq_domain_map,
-};
-
-static int msm_gpio_probe(struct platform_device *pdev)
-{
- int ret, ngpio;
- struct resource *res;
-
- if (of_property_read_u32(pdev->dev.of_node, "ngpio", &ngpio)) {
- dev_err(&pdev->dev, "%s: ngpio property missing\n", __func__);
- return -EINVAL;
- }
-
- if (ngpio > MAX_NR_GPIO)
- WARN(1, "ngpio exceeds the MAX_NR_GPIO. Increase MAX_NR_GPIO\n");
-
- bitmap_zero(msm_gpio.enabled_irqs, MAX_NR_GPIO);
- bitmap_zero(msm_gpio.wake_irqs, MAX_NR_GPIO);
- bitmap_zero(msm_gpio.dual_edge_irqs, MAX_NR_GPIO);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- msm_gpio.msm_tlmm_base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(msm_gpio.msm_tlmm_base))
- return PTR_ERR(msm_gpio.msm_tlmm_base);
-
- msm_gpio.gpio_chip.ngpio = ngpio;
- msm_gpio.gpio_chip.label = pdev->name;
- msm_gpio.gpio_chip.dev = &pdev->dev;
- msm_gpio.gpio_chip.base = 0;
- msm_gpio.gpio_chip.direction_input = msm_gpio_direction_input;
- msm_gpio.gpio_chip.direction_output = msm_gpio_direction_output;
- msm_gpio.gpio_chip.get = msm_gpio_get;
- msm_gpio.gpio_chip.set = msm_gpio_set;
- msm_gpio.gpio_chip.to_irq = msm_gpio_to_irq;
- msm_gpio.gpio_chip.request = msm_gpio_request;
- msm_gpio.gpio_chip.free = msm_gpio_free;
-
- ret = gpiochip_add(&msm_gpio.gpio_chip);
- if (ret < 0) {
- dev_err(&pdev->dev, "gpiochip_add failed with error %d\n", ret);
- return ret;
- }
-
- msm_gpio.summary_irq = platform_get_irq(pdev, 0);
- if (msm_gpio.summary_irq < 0) {
- dev_err(&pdev->dev, "No Summary irq defined for msmgpio\n");
- return msm_gpio.summary_irq;
- }
-
- msm_gpio.domain = irq_domain_add_linear(pdev->dev.of_node, ngpio,
- &msm_gpio_irq_domain_ops,
- &msm_gpio);
- if (!msm_gpio.domain)
- return -ENODEV;
-
- irq_set_chained_handler(msm_gpio.summary_irq, msm_summary_irq_handler);
-
- return 0;
-}
-
-static const struct of_device_id msm_gpio_of_match[] = {
- { .compatible = "qcom,msm-gpio", },
- { },
-};
-MODULE_DEVICE_TABLE(of, msm_gpio_of_match);
-
-static int msm_gpio_remove(struct platform_device *dev)
-{
- gpiochip_remove(&msm_gpio.gpio_chip);
-
- irq_set_handler(msm_gpio.summary_irq, NULL);
-
- return 0;
-}
-
-static struct platform_driver msm_gpio_driver = {
- .probe = msm_gpio_probe,
- .remove = msm_gpio_remove,
- .driver = {
- .name = "msmgpio",
- .of_match_table = msm_gpio_of_match,
- },
-};
-
-module_platform_driver(msm_gpio_driver)
-
-MODULE_AUTHOR("Gregory Bean <gbean@codeaurora.org>");
-MODULE_DESCRIPTION("Driver for Qualcomm MSM TLMMv2 SoC GPIOs");
-MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:msmgpio");
projects / openwrt / staging / blogic.git / commitdiff