397 lines
		
	
	
	
		
			9.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			397 lines
		
	
	
	
		
			9.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * Generic GPIO driver for logic cells found in the Nomadik SoC | ||
|  |  * | ||
|  |  * Copyright (C) 2008,2009 STMicroelectronics | ||
|  |  * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it> | ||
|  |  *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com> | ||
|  |  * | ||
|  |  * 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/kernel.h>
 | ||
|  | #include <linux/module.h>
 | ||
|  | #include <linux/init.h>
 | ||
|  | #include <linux/device.h>
 | ||
|  | #include <linux/amba/bus.h>
 | ||
|  | #include <linux/io.h>
 | ||
|  | #include <linux/gpio.h>
 | ||
|  | #include <linux/spinlock.h>
 | ||
|  | #include <linux/interrupt.h>
 | ||
|  | #include <linux/irq.h>
 | ||
|  | 
 | ||
|  | #include <mach/hardware.h>
 | ||
|  | #include <mach/gpio.h>
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * The GPIO module in the Nomadik family of Systems-on-Chip is an | ||
|  |  * AMBA device, managing 32 pins and alternate functions.  The logic block | ||
|  |  * is currently only used in the Nomadik. | ||
|  |  * | ||
|  |  * Symbols in this file are called "nmk_gpio" for "nomadik gpio" | ||
|  |  */ | ||
|  | 
 | ||
|  | #define NMK_GPIO_PER_CHIP 32
 | ||
|  | struct nmk_gpio_chip { | ||
|  | 	struct gpio_chip chip; | ||
|  | 	void __iomem *addr; | ||
|  | 	unsigned int parent_irq; | ||
|  | 	spinlock_t *lock; | ||
|  | 	/* Keep track of configured edges */ | ||
|  | 	u32 edge_rising; | ||
|  | 	u32 edge_falling; | ||
|  | }; | ||
|  | 
 | ||
|  | /* Mode functions */ | ||
|  | int nmk_gpio_set_mode(int gpio, int gpio_mode) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	unsigned long flags; | ||
|  | 	u32 afunc, bfunc, bit; | ||
|  | 
 | ||
|  | 	nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return -EINVAL; | ||
|  | 
 | ||
|  | 	bit = 1 << (gpio - nmk_chip->chip.base); | ||
|  | 
 | ||
|  | 	spin_lock_irqsave(&nmk_chip->lock, flags); | ||
|  | 	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit; | ||
|  | 	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit; | ||
|  | 	if (gpio_mode & NMK_GPIO_ALT_A) | ||
|  | 		afunc |= bit; | ||
|  | 	if (gpio_mode & NMK_GPIO_ALT_B) | ||
|  | 		bfunc |= bit; | ||
|  | 	writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA); | ||
|  | 	writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB); | ||
|  | 	spin_unlock_irqrestore(&nmk_chip->lock, flags); | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | EXPORT_SYMBOL(nmk_gpio_set_mode); | ||
|  | 
 | ||
|  | int nmk_gpio_get_mode(int gpio) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	u32 afunc, bfunc, bit; | ||
|  | 
 | ||
|  | 	nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return -EINVAL; | ||
|  | 
 | ||
|  | 	bit = 1 << (gpio - nmk_chip->chip.base); | ||
|  | 
 | ||
|  | 	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit; | ||
|  | 	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit; | ||
|  | 
 | ||
|  | 	return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0); | ||
|  | } | ||
|  | EXPORT_SYMBOL(nmk_gpio_get_mode); | ||
|  | 
 | ||
|  | 
 | ||
|  | /* IRQ functions */ | ||
|  | static inline int nmk_gpio_get_bitmask(int gpio) | ||
|  | { | ||
|  | 	return 1 << (gpio % 32); | ||
|  | } | ||
|  | 
 | ||
|  | static void nmk_gpio_irq_ack(unsigned int irq) | ||
|  | { | ||
|  | 	int gpio; | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 
 | ||
|  | 	gpio = NOMADIK_IRQ_TO_GPIO(irq); | ||
|  | 	nmk_chip = get_irq_chip_data(irq); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return; | ||
|  | 	writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC); | ||
|  | } | ||
|  | 
 | ||
|  | static void nmk_gpio_irq_mask(unsigned int irq) | ||
|  | { | ||
|  | 	int gpio; | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	unsigned long flags; | ||
|  | 	u32 bitmask, reg; | ||
|  | 
 | ||
|  | 	gpio = NOMADIK_IRQ_TO_GPIO(irq); | ||
|  | 	nmk_chip = get_irq_chip_data(irq); | ||
|  | 	bitmask = nmk_gpio_get_bitmask(gpio); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return; | ||
|  | 
 | ||
|  | 	/* we must individually clear the two edges */ | ||
|  | 	spin_lock_irqsave(&nmk_chip->lock, flags); | ||
|  | 	if (nmk_chip->edge_rising & bitmask) { | ||
|  | 		reg = readl(nmk_chip->addr + NMK_GPIO_RWIMSC); | ||
|  | 		reg &= ~bitmask; | ||
|  | 		writel(reg, nmk_chip->addr + NMK_GPIO_RWIMSC); | ||
|  | 	} | ||
|  | 	if (nmk_chip->edge_falling & bitmask) { | ||
|  | 		reg = readl(nmk_chip->addr + NMK_GPIO_FWIMSC); | ||
|  | 		reg &= ~bitmask; | ||
|  | 		writel(reg, nmk_chip->addr + NMK_GPIO_FWIMSC); | ||
|  | 	} | ||
|  | 	spin_unlock_irqrestore(&nmk_chip->lock, flags); | ||
|  | }; | ||
|  | 
 | ||
|  | static void nmk_gpio_irq_unmask(unsigned int irq) | ||
|  | { | ||
|  | 	int gpio; | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	unsigned long flags; | ||
|  | 	u32 bitmask, reg; | ||
|  | 
 | ||
|  | 	gpio = NOMADIK_IRQ_TO_GPIO(irq); | ||
|  | 	nmk_chip = get_irq_chip_data(irq); | ||
|  | 	bitmask = nmk_gpio_get_bitmask(gpio); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return; | ||
|  | 
 | ||
|  | 	/* we must individually set the two edges */ | ||
|  | 	spin_lock_irqsave(&nmk_chip->lock, flags); | ||
|  | 	if (nmk_chip->edge_rising & bitmask) { | ||
|  | 		reg = readl(nmk_chip->addr + NMK_GPIO_RWIMSC); | ||
|  | 		reg |= bitmask; | ||
|  | 		writel(reg, nmk_chip->addr + NMK_GPIO_RWIMSC); | ||
|  | 	} | ||
|  | 	if (nmk_chip->edge_falling & bitmask) { | ||
|  | 		reg = readl(nmk_chip->addr + NMK_GPIO_FWIMSC); | ||
|  | 		reg |= bitmask; | ||
|  | 		writel(reg, nmk_chip->addr + NMK_GPIO_FWIMSC); | ||
|  | 	} | ||
|  | 	spin_unlock_irqrestore(&nmk_chip->lock, flags); | ||
|  | } | ||
|  | 
 | ||
|  | static int nmk_gpio_irq_set_type(unsigned int irq, unsigned int type) | ||
|  | { | ||
|  | 	int gpio; | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	unsigned long flags; | ||
|  | 	u32 bitmask; | ||
|  | 
 | ||
|  | 	gpio = NOMADIK_IRQ_TO_GPIO(irq); | ||
|  | 	nmk_chip = get_irq_chip_data(irq); | ||
|  | 	bitmask = nmk_gpio_get_bitmask(gpio); | ||
|  | 	if (!nmk_chip) | ||
|  | 		return -EINVAL; | ||
|  | 
 | ||
|  | 	if (type & IRQ_TYPE_LEVEL_HIGH) | ||
|  | 		return -EINVAL; | ||
|  | 	if (type & IRQ_TYPE_LEVEL_LOW) | ||
|  | 		return -EINVAL; | ||
|  | 
 | ||
|  | 	spin_lock_irqsave(&nmk_chip->lock, flags); | ||
|  | 
 | ||
|  | 	nmk_chip->edge_rising &= ~bitmask; | ||
|  | 	if (type & IRQ_TYPE_EDGE_RISING) | ||
|  | 		nmk_chip->edge_rising |= bitmask; | ||
|  | 	writel(nmk_chip->edge_rising, nmk_chip->addr + NMK_GPIO_RIMSC); | ||
|  | 
 | ||
|  | 	nmk_chip->edge_falling &= ~bitmask; | ||
|  | 	if (type & IRQ_TYPE_EDGE_FALLING) | ||
|  | 		nmk_chip->edge_falling |= bitmask; | ||
|  | 	writel(nmk_chip->edge_falling, nmk_chip->addr + NMK_GPIO_FIMSC); | ||
|  | 
 | ||
|  | 	spin_unlock_irqrestore(&nmk_chip->lock, flags); | ||
|  | 
 | ||
|  | 	nmk_gpio_irq_unmask(irq); | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static struct irq_chip nmk_gpio_irq_chip = { | ||
|  | 	.name		= "Nomadik-GPIO", | ||
|  | 	.ack		= nmk_gpio_irq_ack, | ||
|  | 	.mask		= nmk_gpio_irq_mask, | ||
|  | 	.unmask		= nmk_gpio_irq_unmask, | ||
|  | 	.set_type	= nmk_gpio_irq_set_type, | ||
|  | }; | ||
|  | 
 | ||
|  | static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	struct irq_chip *host_chip; | ||
|  | 	unsigned int gpio_irq; | ||
|  | 	u32 pending; | ||
|  | 	unsigned int first_irq; | ||
|  | 
 | ||
|  | 	nmk_chip = get_irq_data(irq); | ||
|  | 	first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base); | ||
|  | 	while ( (pending = readl(nmk_chip->addr + NMK_GPIO_IS)) ) { | ||
|  | 		gpio_irq = first_irq + __ffs(pending); | ||
|  | 		generic_handle_irq(gpio_irq); | ||
|  | 	} | ||
|  | 	if (0) {/* don't ack parent irq, as ack == disable */ | ||
|  | 		host_chip = get_irq_chip(irq); | ||
|  | 		host_chip->ack(irq); | ||
|  | 	} | ||
|  | } | ||
|  | 
 | ||
|  | static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip) | ||
|  | { | ||
|  | 	unsigned int first_irq; | ||
|  | 	int i; | ||
|  | 
 | ||
|  | 	first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base); | ||
|  | 	for (i = first_irq; i < first_irq + NMK_GPIO_PER_CHIP; i++) { | ||
|  | 		set_irq_chip(i, &nmk_gpio_irq_chip); | ||
|  | 		set_irq_handler(i, handle_edge_irq); | ||
|  | 		set_irq_flags(i, IRQF_VALID); | ||
|  | 		set_irq_chip_data(i, nmk_chip); | ||
|  | 	} | ||
|  | 	set_irq_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler); | ||
|  | 	set_irq_data(nmk_chip->parent_irq, nmk_chip); | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /* I/O Functions */ | ||
|  | static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip = | ||
|  | 		container_of(chip, struct nmk_gpio_chip, chip); | ||
|  | 
 | ||
|  | 	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC); | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset, | ||
|  | 				int val) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip = | ||
|  | 		container_of(chip, struct nmk_gpio_chip, chip); | ||
|  | 
 | ||
|  | 	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS); | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip = | ||
|  | 		container_of(chip, struct nmk_gpio_chip, chip); | ||
|  | 	u32 bit = 1 << offset; | ||
|  | 
 | ||
|  | 	return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0; | ||
|  | } | ||
|  | 
 | ||
|  | static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset, | ||
|  | 				int val) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip = | ||
|  | 		container_of(chip, struct nmk_gpio_chip, chip); | ||
|  | 	u32 bit = 1 << offset; | ||
|  | 
 | ||
|  | 	if (val) | ||
|  | 		writel(bit, nmk_chip->addr + NMK_GPIO_DATS); | ||
|  | 	else | ||
|  | 		writel(bit, nmk_chip->addr + NMK_GPIO_DATC); | ||
|  | } | ||
|  | 
 | ||
|  | /* This structure is replicated for each GPIO block allocated at probe time */ | ||
|  | static struct gpio_chip nmk_gpio_template = { | ||
|  | 	.direction_input	= nmk_gpio_make_input, | ||
|  | 	.get			= nmk_gpio_get_input, | ||
|  | 	.direction_output	= nmk_gpio_make_output, | ||
|  | 	.set			= nmk_gpio_set_output, | ||
|  | 	.ngpio			= NMK_GPIO_PER_CHIP, | ||
|  | 	.can_sleep		= 0, | ||
|  | }; | ||
|  | 
 | ||
|  | static int __init nmk_gpio_probe(struct amba_device *dev, struct amba_id *id) | ||
|  | { | ||
|  | 	struct nmk_gpio_platform_data *pdata; | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 	struct gpio_chip *chip; | ||
|  | 	int ret; | ||
|  | 
 | ||
|  | 	pdata = dev->dev.platform_data; | ||
|  | 	ret = amba_request_regions(dev, pdata->name); | ||
|  | 	if (ret) | ||
|  | 		return ret; | ||
|  | 
 | ||
|  | 	nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL); | ||
|  | 	if (!nmk_chip) { | ||
|  | 		ret = -ENOMEM; | ||
|  | 		goto out_amba; | ||
|  | 	} | ||
|  | 	/*
 | ||
|  | 	 * The virt address in nmk_chip->addr is in the nomadik register space, | ||
|  | 	 * so we can simply convert the resource address, without remapping | ||
|  | 	 */ | ||
|  | 	nmk_chip->addr = io_p2v(dev->res.start); | ||
|  | 	nmk_chip->chip = nmk_gpio_template; | ||
|  | 	nmk_chip->parent_irq = pdata->parent_irq; | ||
|  | 
 | ||
|  | 	chip = &nmk_chip->chip; | ||
|  | 	chip->base = pdata->first_gpio; | ||
|  | 	chip->label = pdata->name; | ||
|  | 	chip->dev = &dev->dev; | ||
|  | 	chip->owner = THIS_MODULE; | ||
|  | 
 | ||
|  | 	ret = gpiochip_add(&nmk_chip->chip); | ||
|  | 	if (ret) | ||
|  | 		goto out_free; | ||
|  | 
 | ||
|  | 	amba_set_drvdata(dev, nmk_chip); | ||
|  | 
 | ||
|  | 	nmk_gpio_init_irq(nmk_chip); | ||
|  | 
 | ||
|  | 	dev_info(&dev->dev, "Bits %i-%i at address %p\n", | ||
|  | 		 nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr); | ||
|  | 	return 0; | ||
|  | 
 | ||
|  |  out_free: | ||
|  | 	kfree(nmk_chip); | ||
|  |  out_amba: | ||
|  | 	amba_release_regions(dev); | ||
|  | 	dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret, | ||
|  | 		  pdata->first_gpio, pdata->first_gpio+31); | ||
|  | 	return ret; | ||
|  | } | ||
|  | 
 | ||
|  | static int nmk_gpio_remove(struct amba_device *dev) | ||
|  | { | ||
|  | 	struct nmk_gpio_chip *nmk_chip; | ||
|  | 
 | ||
|  | 	nmk_chip = amba_get_drvdata(dev); | ||
|  | 	gpiochip_remove(&nmk_chip->chip); | ||
|  | 	kfree(nmk_chip); | ||
|  | 	amba_release_regions(dev); | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | /* We have 0x1f080060 and 0x1f180060, accept both using the mask */ | ||
|  | static struct amba_id nmk_gpio_ids[] = { | ||
|  | 	{ | ||
|  | 		.id	= 0x1f080060, | ||
|  | 		.mask	= 0xffefffff, | ||
|  | 	}, | ||
|  | 	{0, 0}, | ||
|  | }; | ||
|  | 
 | ||
|  | static struct amba_driver nmk_gpio_driver = { | ||
|  | 	.drv = { | ||
|  | 		.owner = THIS_MODULE, | ||
|  | 		.name = "gpio", | ||
|  | 		}, | ||
|  | 	.probe = nmk_gpio_probe, | ||
|  | 	.remove = nmk_gpio_remove, | ||
|  | 	.suspend = NULL, /* to be done */ | ||
|  | 	.resume = NULL, | ||
|  | 	.id_table = nmk_gpio_ids, | ||
|  | }; | ||
|  | 
 | ||
|  | static int __init nmk_gpio_init(void) | ||
|  | { | ||
|  | 	return amba_driver_register(&nmk_gpio_driver); | ||
|  | } | ||
|  | 
 | ||
|  | arch_initcall(nmk_gpio_init); | ||
|  | 
 | ||
|  | MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini"); | ||
|  | MODULE_DESCRIPTION("Nomadik GPIO Driver"); | ||
|  | MODULE_LICENSE("GPL"); | ||
|  | 
 | ||
|  | 
 |