linux/drivers/gpio/gpio-ftgpio010.c
Linus Torvalds 6aa2f9441f This is the bulk of GPIO changes for the v4.15 kernel cycle:
CORE:
 - Fix the semantics of raw GPIO to actually be raw. No
   inversion semantics as before, but also no open draining,
   and allow the raw operations to affect lines used for
   interrupts as the caller supposedly knows what they are
   doing if they are getting the big hammer.
 
 - Rewrote the __inner_function() notation calls to names that
   make more sense. I just find this kind of code disturbing.
 
 - Drop the .irq_base() field from the gpiochip since now all
   IRQs are mapped dynamically. This is nice.
 
 - Support for .get_multiple() in the core driver API. This
   allows us to read several GPIO lines with a single
   register read. This has high value for some usecases: it
   can be used to create oscilloscopes and signal analyzers
   and other things that rely on reading several lines at
   exactly the same instant. Also a generally nice
   optimization. This uses the new assign_bit() macro from
   the bitops lib that was ACKed by Andrew Morton and
   is implemented for two drivers, one of them being the
   generic MMIO driver so everyone using that will be able
   to benefit from this.
 
 - Do not allow requests of Open Drain and Open Source
   setting of a GPIO line simultaneously. If the hardware
   actually supports enabling both at the same time the
   electrical result would be disastrous.
 
 - A new interrupt chip core helper. This will be helpful
   to deal with "banked" GPIOs, which means GPIO controllers
   with several logical blocks of GPIO inside them. This
   is several gpiochips per device in the device model, in
   contrast to the case when there is a 1-to-1 relationship
   between a device and a gpiochip.
 
 NEW DRIVERS:
 
 - Maxim MAX3191x industrial serializer, a very interesting
   piece of professional I/O hardware.
 
 - Uniphier GPIO driver. This is the GPIO block from the
   recent Socionext (ex Fujitsu and Panasonic) platform.
 
 - Tegra 186 driver. This is based on the new banked GPIO
   infrastructure.
 
 OTHER IMPROVEMENTS:
 
 - Some documentation improvements.
 
 - Wakeup support for the DesignWare DWAPB GPIO controller.
 
 - Reset line support on the DesignWare DWAPB GPIO controller.
 
 - Several non-critical bug fixes and improvements for the
   Broadcom BRCMSTB driver.
 
 - Misc non-critical bug fixes like exotic errorpaths, removal
   of dead code etc.
 
 - Explicit comments on fall-through switch() statements.
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Merge tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.15 kernel cycle:

  Core:

   - Fix the semantics of raw GPIO to actually be raw. No inversion
     semantics as before, but also no open draining, and allow the raw
     operations to affect lines used for interrupts as the caller
     supposedly knows what they are doing if they are getting the big
     hammer.

   - Rewrote the __inner_function() notation calls to names that make
     more sense. I just find this kind of code disturbing.

   - Drop the .irq_base() field from the gpiochip since now all IRQs are
     mapped dynamically. This is nice.

   - Support for .get_multiple() in the core driver API. This allows us
     to read several GPIO lines with a single register read. This has
     high value for some usecases: it can be used to create
     oscilloscopes and signal analyzers and other things that rely on
     reading several lines at exactly the same instant. Also a generally
     nice optimization. This uses the new assign_bit() macro from the
     bitops lib that was ACKed by Andrew Morton and is implemented for
     two drivers, one of them being the generic MMIO driver so everyone
     using that will be able to benefit from this.

   - Do not allow requests of Open Drain and Open Source setting of a
     GPIO line simultaneously. If the hardware actually supports
     enabling both at the same time the electrical result would be
     disastrous.

   - A new interrupt chip core helper. This will be helpful to deal with
     "banked" GPIOs, which means GPIO controllers with several logical
     blocks of GPIO inside them. This is several gpiochips per device in
     the device model, in contrast to the case when there is a 1-to-1
     relationship between a device and a gpiochip.

  New drivers:

   - Maxim MAX3191x industrial serializer, a very interesting piece of
     professional I/O hardware.

   - Uniphier GPIO driver. This is the GPIO block from the recent
     Socionext (ex Fujitsu and Panasonic) platform.

   - Tegra 186 driver. This is based on the new banked GPIO
     infrastructure.

  Other improvements:

   - Some documentation improvements.

   - Wakeup support for the DesignWare DWAPB GPIO controller.

   - Reset line support on the DesignWare DWAPB GPIO controller.

   - Several non-critical bug fixes and improvements for the Broadcom
     BRCMSTB driver.

   - Misc non-critical bug fixes like exotic errorpaths, removal of dead
     code etc.

   - Explicit comments on fall-through switch() statements"

* tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (65 commits)
  gpio: tegra186: Remove tegra186_gpio_lock_class
  gpio: rcar: Add r8a77995 (R-Car D3) support
  pinctrl: bcm2835: Fix some merge fallout
  gpio: Fix undefined lock_dep_class
  gpio: Automatically add lockdep keys
  gpio: Introduce struct gpio_irq_chip.first
  gpio: Disambiguate struct gpio_irq_chip.nested
  gpio: Add Tegra186 support
  gpio: Export gpiochip_irq_{map,unmap}()
  gpio: Implement tighter IRQ chip integration
  gpio: Move lock_key into struct gpio_irq_chip
  gpio: Move irq_valid_mask into struct gpio_irq_chip
  gpio: Move irq_nested into struct gpio_irq_chip
  gpio: Move irq_chained_parent to struct gpio_irq_chip
  gpio: Move irq_default_type to struct gpio_irq_chip
  gpio: Move irq_handler to struct gpio_irq_chip
  gpio: Move irqdomain into struct gpio_irq_chip
  gpio: Move irqchip into struct gpio_irq_chip
  gpio: Introduce struct gpio_irq_chip
  pinctrl: armada-37xx: remove unused variable
  ...
2017-11-14 17:23:44 -08:00

244 lines
5.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Faraday Technolog FTGPIO010 gpiochip and interrupt routines
* Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
*
* Based on arch/arm/mach-gemini/gpio.c:
* Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
*
* Based on plat-mxc/gpio.c:
* MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
*/
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/of_gpio.h>
#include <linux/bitops.h>
/* GPIO registers definition */
#define GPIO_DATA_OUT 0x00
#define GPIO_DATA_IN 0x04
#define GPIO_DIR 0x08
#define GPIO_DATA_SET 0x10
#define GPIO_DATA_CLR 0x14
#define GPIO_PULL_EN 0x18
#define GPIO_PULL_TYPE 0x1C
#define GPIO_INT_EN 0x20
#define GPIO_INT_STAT 0x24
#define GPIO_INT_MASK 0x2C
#define GPIO_INT_CLR 0x30
#define GPIO_INT_TYPE 0x34
#define GPIO_INT_BOTH_EDGE 0x38
#define GPIO_INT_LEVEL 0x3C
#define GPIO_DEBOUNCE_EN 0x40
#define GPIO_DEBOUNCE_PRESCALE 0x44
/**
* struct ftgpio_gpio - Gemini GPIO state container
* @dev: containing device for this instance
* @gc: gpiochip for this instance
*/
struct ftgpio_gpio {
struct device *dev;
struct gpio_chip gc;
void __iomem *base;
};
static void ftgpio_gpio_ack_irq(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ftgpio_gpio *g = gpiochip_get_data(gc);
writel(BIT(irqd_to_hwirq(d)), g->base + GPIO_INT_CLR);
}
static void ftgpio_gpio_mask_irq(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ftgpio_gpio *g = gpiochip_get_data(gc);
u32 val;
val = readl(g->base + GPIO_INT_EN);
val &= ~BIT(irqd_to_hwirq(d));
writel(val, g->base + GPIO_INT_EN);
}
static void ftgpio_gpio_unmask_irq(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ftgpio_gpio *g = gpiochip_get_data(gc);
u32 val;
val = readl(g->base + GPIO_INT_EN);
val |= BIT(irqd_to_hwirq(d));
writel(val, g->base + GPIO_INT_EN);
}
static int ftgpio_gpio_set_irq_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ftgpio_gpio *g = gpiochip_get_data(gc);
u32 mask = BIT(irqd_to_hwirq(d));
u32 reg_both, reg_level, reg_type;
reg_type = readl(g->base + GPIO_INT_TYPE);
reg_level = readl(g->base + GPIO_INT_LEVEL);
reg_both = readl(g->base + GPIO_INT_BOTH_EDGE);
switch (type) {
case IRQ_TYPE_EDGE_BOTH:
irq_set_handler_locked(d, handle_edge_irq);
reg_type &= ~mask;
reg_both |= mask;
break;
case IRQ_TYPE_EDGE_RISING:
irq_set_handler_locked(d, handle_edge_irq);
reg_type &= ~mask;
reg_both &= ~mask;
reg_level &= ~mask;
break;
case IRQ_TYPE_EDGE_FALLING:
irq_set_handler_locked(d, handle_edge_irq);
reg_type &= ~mask;
reg_both &= ~mask;
reg_level |= mask;
break;
case IRQ_TYPE_LEVEL_HIGH:
irq_set_handler_locked(d, handle_level_irq);
reg_type |= mask;
reg_level &= ~mask;
break;
case IRQ_TYPE_LEVEL_LOW:
irq_set_handler_locked(d, handle_level_irq);
reg_type |= mask;
reg_level |= mask;
break;
default:
irq_set_handler_locked(d, handle_bad_irq);
return -EINVAL;
}
writel(reg_type, g->base + GPIO_INT_TYPE);
writel(reg_level, g->base + GPIO_INT_LEVEL);
writel(reg_both, g->base + GPIO_INT_BOTH_EDGE);
ftgpio_gpio_ack_irq(d);
return 0;
}
static struct irq_chip ftgpio_gpio_irqchip = {
.name = "FTGPIO010",
.irq_ack = ftgpio_gpio_ack_irq,
.irq_mask = ftgpio_gpio_mask_irq,
.irq_unmask = ftgpio_gpio_unmask_irq,
.irq_set_type = ftgpio_gpio_set_irq_type,
};
static void ftgpio_gpio_irq_handler(struct irq_desc *desc)
{
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct ftgpio_gpio *g = gpiochip_get_data(gc);
struct irq_chip *irqchip = irq_desc_get_chip(desc);
int offset;
unsigned long stat;
chained_irq_enter(irqchip, desc);
stat = readl(g->base + GPIO_INT_STAT);
if (stat)
for_each_set_bit(offset, &stat, gc->ngpio)
generic_handle_irq(irq_find_mapping(gc->irq.domain,
offset));
chained_irq_exit(irqchip, desc);
}
static int ftgpio_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct ftgpio_gpio *g;
int irq;
int ret;
g = devm_kzalloc(dev, sizeof(*g), GFP_KERNEL);
if (!g)
return -ENOMEM;
g->dev = dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
g->base = devm_ioremap_resource(dev, res);
if (IS_ERR(g->base))
return PTR_ERR(g->base);
irq = platform_get_irq(pdev, 0);
if (!irq)
return -EINVAL;
ret = bgpio_init(&g->gc, dev, 4,
g->base + GPIO_DATA_IN,
g->base + GPIO_DATA_SET,
g->base + GPIO_DATA_CLR,
g->base + GPIO_DIR,
NULL,
0);
if (ret) {
dev_err(dev, "unable to init generic GPIO\n");
return ret;
}
g->gc.label = "FTGPIO010";
g->gc.base = -1;
g->gc.parent = dev;
g->gc.owner = THIS_MODULE;
/* ngpio is set by bgpio_init() */
ret = devm_gpiochip_add_data(dev, &g->gc, g);
if (ret)
return ret;
/* Disable, unmask and clear all interrupts */
writel(0x0, g->base + GPIO_INT_EN);
writel(0x0, g->base + GPIO_INT_MASK);
writel(~0x0, g->base + GPIO_INT_CLR);
ret = gpiochip_irqchip_add(&g->gc, &ftgpio_gpio_irqchip,
0, handle_bad_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_info(dev, "could not add irqchip\n");
return ret;
}
gpiochip_set_chained_irqchip(&g->gc, &ftgpio_gpio_irqchip,
irq, ftgpio_gpio_irq_handler);
dev_info(dev, "FTGPIO010 @%p registered\n", g->base);
return 0;
}
static const struct of_device_id ftgpio_gpio_of_match[] = {
{
.compatible = "cortina,gemini-gpio",
},
{
.compatible = "moxa,moxart-gpio",
},
{
.compatible = "faraday,ftgpio010",
},
{},
};
static struct platform_driver ftgpio_gpio_driver = {
.driver = {
.name = "ftgpio010-gpio",
.of_match_table = of_match_ptr(ftgpio_gpio_of_match),
},
.probe = ftgpio_gpio_probe,
};
builtin_platform_driver(ftgpio_gpio_driver);