forked from mirrors/linux
		
	gpio: add driver for MEN 16Z127 GPIO controller
The 16Z127 is a 32bit GPIO controller on a MCB FPGA. Every single line can be configured as input and output. Push pull and open drain are supported as well as setting a debounce value for the input lines. Signed-off-by: Andreas Werner <andy@wernerandy.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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		|  | @ -270,6 +270,13 @@ config GPIO_MB86S7X | |||
| 	help | ||||
| 	  Say yes here to support the GPIO controller in Fujitsu MB86S70 SoCs. | ||||
| 
 | ||||
| config GPIO_MENZ127 | ||||
| 	tristate "MEN 16Z127 GPIO support" | ||||
| 	depends on MCB | ||||
| 	select GPIO_GENERIC | ||||
| 	help | ||||
| 	 Say yes here to support the MEN 16Z127 GPIO Controller | ||||
| 
 | ||||
| config GPIO_MM_LANTIQ | ||||
| 	bool "Lantiq Memory mapped GPIOs" | ||||
| 	depends on LANTIQ && SOC_XWAY | ||||
|  |  | |||
|  | @ -59,6 +59,7 @@ obj-$(CONFIG_GPIO_MAX7300)	+= gpio-max7300.o | |||
| obj-$(CONFIG_GPIO_MAX7301)	+= gpio-max7301.o | ||||
| obj-$(CONFIG_GPIO_MAX732X)	+= gpio-max732x.o | ||||
| obj-$(CONFIG_GPIO_MB86S7X)	+= gpio-mb86s7x.o | ||||
| obj-$(CONFIG_GPIO_MENZ127)	+= gpio-menz127.o | ||||
| obj-$(CONFIG_GPIO_MC33880)	+= gpio-mc33880.o | ||||
| obj-$(CONFIG_GPIO_MC9S08DZ60)	+= gpio-mc9s08dz60.o | ||||
| obj-$(CONFIG_GPIO_MCP23S08)	+= gpio-mcp23s08.o | ||||
|  |  | |||
							
								
								
									
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								drivers/gpio/gpio-menz127.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
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								drivers/gpio/gpio-menz127.c
									
									
									
									
									
										Normal file
									
								
							|  | @ -0,0 +1,200 @@ | |||
| /*
 | ||||
|  * MEN 16Z127 GPIO driver | ||||
|  * | ||||
|  * Copyright (C) 2016 MEN Mikroelektronik GmbH (www.men.de) | ||||
|  * | ||||
|  * 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; version 2 of the License. | ||||
|  */ | ||||
| 
 | ||||
| #include <linux/kernel.h> | ||||
| #include <linux/module.h> | ||||
| #include <linux/io.h> | ||||
| #include <linux/err.h> | ||||
| #include <linux/mcb.h> | ||||
| #include <linux/bitops.h> | ||||
| #include <linux/gpio/driver.h> | ||||
| 
 | ||||
| #define MEN_Z127_CTRL	0x00 | ||||
| #define MEN_Z127_PSR	0x04 | ||||
| #define MEN_Z127_IRQR	0x08 | ||||
| #define MEN_Z127_GPIODR	0x0c | ||||
| #define MEN_Z127_IER1	0x10 | ||||
| #define MEN_Z127_IER2	0x14 | ||||
| #define MEN_Z127_DBER	0x18 | ||||
| #define MEN_Z127_ODER	0x1C | ||||
| #define GPIO_TO_DBCNT_REG(gpio)	((gpio * 4) + 0x80) | ||||
| 
 | ||||
| #define MEN_Z127_DB_MIN_US	50 | ||||
| /* 16 bit compare register. Each bit represents 50us */ | ||||
| #define MEN_Z127_DB_MAX_US	(0xffff * MEN_Z127_DB_MIN_US) | ||||
| #define MEN_Z127_DB_IN_RANGE(db)	((db >= MEN_Z127_DB_MIN_US) && \ | ||||
| 					 (db <= MEN_Z127_DB_MAX_US)) | ||||
| 
 | ||||
| struct men_z127_gpio { | ||||
| 	struct gpio_chip gc; | ||||
| 	void __iomem *reg_base; | ||||
| 	struct mcb_device *mdev; | ||||
| 	struct resource *mem; | ||||
| 	spinlock_t lock; | ||||
| }; | ||||
| 
 | ||||
| static int men_z127_debounce(struct gpio_chip *gc, unsigned gpio, | ||||
| 			     unsigned debounce) | ||||
| { | ||||
| 	struct men_z127_gpio *priv = gpiochip_get_data(gc); | ||||
| 	struct device *dev = &priv->mdev->dev; | ||||
| 	unsigned int rnd; | ||||
| 	u32 db_en, db_cnt; | ||||
| 
 | ||||
| 	if (!MEN_Z127_DB_IN_RANGE(debounce)) { | ||||
| 		dev_err(dev, "debounce value %u out of range", debounce); | ||||
| 		return -EINVAL; | ||||
| 	} | ||||
| 
 | ||||
| 	if (debounce > 0) { | ||||
| 		/* round up or down depending on MSB-1 */ | ||||
| 		rnd = fls(debounce) - 1; | ||||
| 
 | ||||
| 		if (rnd && (debounce & BIT(rnd - 1))) | ||||
| 			debounce = round_up(debounce, MEN_Z127_DB_MIN_US); | ||||
| 		else | ||||
| 			debounce = round_down(debounce, MEN_Z127_DB_MIN_US); | ||||
| 
 | ||||
| 		if (debounce > MEN_Z127_DB_MAX_US) | ||||
| 			debounce = MEN_Z127_DB_MAX_US; | ||||
| 
 | ||||
| 		/* 50us per register unit */ | ||||
| 		debounce /= 50; | ||||
| 	} | ||||
| 
 | ||||
| 	spin_lock(&priv->lock); | ||||
| 
 | ||||
| 	db_en = readl(priv->reg_base + MEN_Z127_DBER); | ||||
| 
 | ||||
| 	if (debounce == 0) { | ||||
| 		db_en &= ~BIT(gpio); | ||||
| 		db_cnt = 0; | ||||
| 	} else { | ||||
| 		db_en |= BIT(gpio); | ||||
| 		db_cnt = debounce; | ||||
| 	} | ||||
| 
 | ||||
| 	writel(db_en, priv->reg_base + MEN_Z127_DBER); | ||||
| 	writel(db_cnt, priv->reg_base + GPIO_TO_DBCNT_REG(gpio)); | ||||
| 
 | ||||
| 	spin_unlock(&priv->lock); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int men_z127_request(struct gpio_chip *gc, unsigned gpio_pin) | ||||
| { | ||||
| 	struct men_z127_gpio *priv = gpiochip_get_data(gc); | ||||
| 	u32 od_en; | ||||
| 
 | ||||
| 	if (gpio_pin >= gc->ngpio) | ||||
| 		return -EINVAL; | ||||
| 
 | ||||
| 	spin_lock(&priv->lock); | ||||
| 	od_en = readl(priv->reg_base + MEN_Z127_ODER); | ||||
| 
 | ||||
| 	if (gpiochip_line_is_open_drain(gc, gpio_pin)) | ||||
| 		od_en |= BIT(gpio_pin); | ||||
| 	else | ||||
| 		od_en &= ~BIT(gpio_pin); | ||||
| 
 | ||||
| 	writel(od_en, priv->reg_base + MEN_Z127_ODER); | ||||
| 	spin_unlock(&priv->lock); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int men_z127_probe(struct mcb_device *mdev, | ||||
| 			  const struct mcb_device_id *id) | ||||
| { | ||||
| 	struct men_z127_gpio *men_z127_gpio; | ||||
| 	struct device *dev = &mdev->dev; | ||||
| 	int ret; | ||||
| 
 | ||||
| 	men_z127_gpio = devm_kzalloc(dev, sizeof(struct men_z127_gpio), | ||||
| 				     GFP_KERNEL); | ||||
| 	if (!men_z127_gpio) | ||||
| 		return -ENOMEM; | ||||
| 
 | ||||
| 	men_z127_gpio->mem = mcb_request_mem(mdev, dev_name(dev)); | ||||
| 	if (IS_ERR(men_z127_gpio->mem)) { | ||||
| 		dev_err(dev, "failed to request device memory"); | ||||
| 		return PTR_ERR(men_z127_gpio->mem); | ||||
| 	} | ||||
| 
 | ||||
| 	men_z127_gpio->reg_base = ioremap(men_z127_gpio->mem->start, | ||||
| 					  resource_size(men_z127_gpio->mem)); | ||||
| 	if (men_z127_gpio->reg_base == NULL) { | ||||
| 		ret = -ENXIO; | ||||
| 		goto err_release; | ||||
| 	} | ||||
| 
 | ||||
| 	men_z127_gpio->mdev = mdev; | ||||
| 	mcb_set_drvdata(mdev, men_z127_gpio); | ||||
| 
 | ||||
| 	ret = bgpio_init(&men_z127_gpio->gc, &mdev->dev, 4, | ||||
| 			 men_z127_gpio->reg_base + MEN_Z127_PSR, | ||||
| 			 men_z127_gpio->reg_base + MEN_Z127_CTRL, | ||||
| 			 NULL, | ||||
| 			 men_z127_gpio->reg_base + MEN_Z127_GPIODR, | ||||
| 			 NULL, 0); | ||||
| 	if (ret) | ||||
| 		goto err_unmap; | ||||
| 
 | ||||
| 	men_z127_gpio->gc.set_debounce = men_z127_debounce; | ||||
| 	men_z127_gpio->gc.request = men_z127_request; | ||||
| 
 | ||||
| 	ret = gpiochip_add_data(&men_z127_gpio->gc, men_z127_gpio); | ||||
| 	if (ret) { | ||||
| 		dev_err(dev, "failed to register MEN 16Z127 GPIO controller"); | ||||
| 		goto err_unmap; | ||||
| 	} | ||||
| 
 | ||||
| 	dev_info(dev, "MEN 16Z127 GPIO driver registered"); | ||||
| 
 | ||||
| 	return 0; | ||||
| 
 | ||||
| err_unmap: | ||||
| 	iounmap(men_z127_gpio->reg_base); | ||||
| err_release: | ||||
| 	mcb_release_mem(men_z127_gpio->mem); | ||||
| 	return ret; | ||||
| } | ||||
| 
 | ||||
| static void men_z127_remove(struct mcb_device *mdev) | ||||
| { | ||||
| 	struct men_z127_gpio *men_z127_gpio = mcb_get_drvdata(mdev); | ||||
| 
 | ||||
| 	gpiochip_remove(&men_z127_gpio->gc); | ||||
| 	iounmap(men_z127_gpio->reg_base); | ||||
| 	mcb_release_mem(men_z127_gpio->mem); | ||||
| } | ||||
| 
 | ||||
| static const struct mcb_device_id men_z127_ids[] = { | ||||
| 	{ .device = 0x7f }, | ||||
| 	{ } | ||||
| }; | ||||
| MODULE_DEVICE_TABLE(mcb, men_z127_ids); | ||||
| 
 | ||||
| static struct mcb_driver men_z127_driver = { | ||||
| 	.driver = { | ||||
| 		.name = "z127-gpio", | ||||
| 		.owner = THIS_MODULE, | ||||
| 	}, | ||||
| 	.probe = men_z127_probe, | ||||
| 	.remove = men_z127_remove, | ||||
| 	.id_table = men_z127_ids, | ||||
| }; | ||||
| module_mcb_driver(men_z127_driver); | ||||
| 
 | ||||
| MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>"); | ||||
| MODULE_DESCRIPTION("MEN 16z127 GPIO Controller"); | ||||
| MODULE_LICENSE("GPL v2"); | ||||
| MODULE_ALIAS("mcb:16z127"); | ||||
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