diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-18 08:22:10 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-18 08:22:10 -0400 |
commit | 510965dd4a0a59504ba38455f77339ea8b4c6a70 (patch) | |
tree | 36492629ac68de94457482562660154f28e9e039 /drivers/gpio/gpio-altera.c | |
parent | 40d7839879b4584f91522d841afb22ed401cf40f (diff) | |
parent | 03daa6f82f2b634019fe8261698f6af3c133497f (diff) |
Merge tag 'gpio-v4.1-1' of git://git.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 v4.1 development cycle:
- A new GPIO hogging mechanism has been added. This can be used on
boards that want to drive some GPIO line high, low, or set it as
input on boot and then never touch it again. For some embedded
systems this is bliss and simplifies things to a great extent.
- Some API cleanup and closure: gpiod_get_array() and
gpiod_put_array() has been added to get and put GPIOs in bulk as
was possible with the non-descriptor API.
- Encapsulate cross-calls to the pin control subsystem in
<linux/gpio/driver.h>. Now this should be the only header any GPIO
driver needs to include or something is wrong. Cleanups
restricting drivers to this include are welcomed if tested.
- Sort the GPIO Kconfig and split it into submenus, as it was
becoming and unstructured, illogical and unnavigatable mess. I
hope this is easier to follow. Menus that require a certain
subsystem like I2C can now be hidden nicely for example, still
working on others.
- New drivers:
- New driver for the Altera Soft GPIO.
- The F7188x driver now handles the F71869 and F71869A variants.
- The MIPS Loongson driver has been moved to drivers/gpio for
consolidation and cleanup.
- Cleanups:
- The MAX732x is converted to use the GPIOLIB_IRQCHIP
infrastructure.
- The PCF857x is converted to use the GPIOLIB_IRQCHIP
infrastructure.
- Radical cleanup of the OMAP driver.
- Misc:
- Enable the DWAPB GPIO for all architectures. This is a "hard
IP" block from Synopsys which has started to turn up in so
diverse architectures as X86 Quark, ARC and a slew of ARM
systems. So even though it's not an expander, it's generic
enough to be available for all.
- We add a mock GPIO on Crystalcove PMIC after a long discussion
with Daniel Vetter et al, tracing back to the shootout at the
kernel summit where DRM drivers and sub-componentization was
discussed. In this case a mock GPIO is assumed to be the best
compromise gaining some reuse of infrastructure without making
DRM drivers overly complex at the same time. Let's see"
* tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits)
Revert "gpio: sch: use uapi/linux/pci_ids.h directly"
gpio: dwapb: remove dependencies
gpio: dwapb: enable for ARC
gpio: removing kfree remove functionality
gpio: mvebu: Fix mask/unmask managment per irq chip type
gpio: split GPIO drivers in submenus
gpio: move MFD GPIO drivers under their own comment
gpio: move BCM Kona Kconfig option
gpio: arrange SPI Kconfig symbols alphabetically
gpio: arrange PCI GPIO controllers alphabetically
gpio: arrange I2C Kconfig symbols alphabetically
gpio: arrange Kconfig symbols alphabetically
gpio: ich: Implement get_direction function
gpio: use (!foo) instead of (foo == NULL)
gpio: arizona: drop owner assignment from platform_drivers
gpio: max7300: remove 'ret' variable
gpio: use devm_kzalloc
gpio: sch: use uapi/linux/pci_ids.h directly
gpio: x-gene: fix devm_ioremap_resource() check
gpio: loongson: Add Loongson-3A/3B GPIO driver support
...
Diffstat (limited to 'drivers/gpio/gpio-altera.c')
-rw-r--r-- | drivers/gpio/gpio-altera.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c new file mode 100644 index 000000000000..449fb46cb8a0 --- /dev/null +++ b/drivers/gpio/gpio-altera.c @@ -0,0 +1,374 @@ +/* + * Copyright (C) 2013 Altera Corporation + * Based on gpio-mpc8xxx.c + * + * 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, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/io.h> +#include <linux/of_gpio.h> +#include <linux/platform_device.h> + +#define ALTERA_GPIO_MAX_NGPIO 32 +#define ALTERA_GPIO_DATA 0x0 +#define ALTERA_GPIO_DIR 0x4 +#define ALTERA_GPIO_IRQ_MASK 0x8 +#define ALTERA_GPIO_EDGE_CAP 0xc + +/** +* struct altera_gpio_chip +* @mmchip : memory mapped chip structure. +* @gpio_lock : synchronization lock so that new irq/set/get requests + will be blocked until the current one completes. +* @interrupt_trigger : specifies the hardware configured IRQ trigger type + (rising, falling, both, high) +* @mapped_irq : kernel mapped irq number. +*/ +struct altera_gpio_chip { + struct of_mm_gpio_chip mmchip; + spinlock_t gpio_lock; + int interrupt_trigger; + int mapped_irq; +}; + +static void altera_gpio_irq_unmask(struct irq_data *d) +{ + struct altera_gpio_chip *altera_gc; + struct of_mm_gpio_chip *mm_gc; + unsigned long flags; + u32 intmask; + + altera_gc = irq_data_get_irq_chip_data(d); + mm_gc = &altera_gc->mmchip; + + spin_lock_irqsave(&altera_gc->gpio_lock, flags); + intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + /* Set ALTERA_GPIO_IRQ_MASK bit to unmask */ + intmask |= BIT(irqd_to_hwirq(d)); + writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); +} + +static void altera_gpio_irq_mask(struct irq_data *d) +{ + struct altera_gpio_chip *altera_gc; + struct of_mm_gpio_chip *mm_gc; + unsigned long flags; + u32 intmask; + + altera_gc = irq_data_get_irq_chip_data(d); + mm_gc = &altera_gc->mmchip; + + spin_lock_irqsave(&altera_gc->gpio_lock, flags); + intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + /* Clear ALTERA_GPIO_IRQ_MASK bit to mask */ + intmask &= ~BIT(irqd_to_hwirq(d)); + writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); +} + +/** + * This controller's IRQ type is synthesized in hardware, so this function + * just checks if the requested set_type matches the synthesized IRQ type + */ +static int altera_gpio_irq_set_type(struct irq_data *d, + unsigned int type) +{ + struct altera_gpio_chip *altera_gc; + + altera_gc = irq_data_get_irq_chip_data(d); + + if (type == IRQ_TYPE_NONE) + return 0; + if (type == IRQ_TYPE_LEVEL_HIGH && + altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH) + return 0; + if (type == IRQ_TYPE_EDGE_RISING && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_RISING) + return 0; + if (type == IRQ_TYPE_EDGE_FALLING && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_FALLING) + return 0; + if (type == IRQ_TYPE_EDGE_BOTH && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_BOTH) + return 0; + + return -EINVAL; +} + +static unsigned int altera_gpio_irq_startup(struct irq_data *d) { + altera_gpio_irq_unmask(d); + + return 0; +} + +static struct irq_chip altera_irq_chip = { + .name = "altera-gpio", + .irq_mask = altera_gpio_irq_mask, + .irq_unmask = altera_gpio_irq_unmask, + .irq_set_type = altera_gpio_irq_set_type, + .irq_startup = altera_gpio_irq_startup, + .irq_shutdown = altera_gpio_irq_mask, +}; + +static int altera_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + struct of_mm_gpio_chip *mm_gc; + + mm_gc = to_of_mm_gpio_chip(gc); + + return !!(readl(mm_gc->regs + ALTERA_GPIO_DATA) & BIT(offset)); +} + +static void altera_gpio_set(struct gpio_chip *gc, unsigned offset, int value) +{ + struct of_mm_gpio_chip *mm_gc; + struct altera_gpio_chip *chip; + unsigned long flags; + unsigned int data_reg; + + mm_gc = to_of_mm_gpio_chip(gc); + chip = container_of(mm_gc, struct altera_gpio_chip, mmchip); + + spin_lock_irqsave(&chip->gpio_lock, flags); + data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); + if (value) + data_reg |= BIT(offset); + else + data_reg &= ~BIT(offset); + writel(data_reg, mm_gc->regs + ALTERA_GPIO_DATA); + spin_unlock_irqrestore(&chip->gpio_lock, flags); +} + +static int altera_gpio_direction_input(struct gpio_chip *gc, unsigned offset) +{ + struct of_mm_gpio_chip *mm_gc; + struct altera_gpio_chip *chip; + unsigned long flags; + unsigned int gpio_ddr; + + mm_gc = to_of_mm_gpio_chip(gc); + chip = container_of(mm_gc, struct altera_gpio_chip, mmchip); + + spin_lock_irqsave(&chip->gpio_lock, flags); + /* Set pin as input, assumes software controlled IP */ + gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); + gpio_ddr &= ~BIT(offset); + writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); + spin_unlock_irqrestore(&chip->gpio_lock, flags); + + return 0; +} + +static int altera_gpio_direction_output(struct gpio_chip *gc, + unsigned offset, int value) +{ + struct of_mm_gpio_chip *mm_gc; + struct altera_gpio_chip *chip; + unsigned long flags; + unsigned int data_reg, gpio_ddr; + + mm_gc = to_of_mm_gpio_chip(gc); + chip = container_of(mm_gc, struct altera_gpio_chip, mmchip); + + spin_lock_irqsave(&chip->gpio_lock, flags); + /* Sets the GPIO value */ + data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); + if (value) + data_reg |= BIT(offset); + else + data_reg &= ~BIT(offset); + writel(data_reg, mm_gc->regs + ALTERA_GPIO_DATA); + + /* Set pin as output, assumes software controlled IP */ + gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); + gpio_ddr |= BIT(offset); + writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); + spin_unlock_irqrestore(&chip->gpio_lock, flags); + + return 0; +} + +static void altera_gpio_irq_edge_handler(unsigned int irq, + struct irq_desc *desc) +{ + struct altera_gpio_chip *altera_gc; + struct irq_chip *chip; + struct of_mm_gpio_chip *mm_gc; + struct irq_domain *irqdomain; + unsigned long status; + int i; + + altera_gc = irq_desc_get_handler_data(desc); + chip = irq_desc_get_chip(desc); + mm_gc = &altera_gc->mmchip; + irqdomain = altera_gc->mmchip.gc.irqdomain; + + chained_irq_enter(chip, desc); + + while ((status = + (readl(mm_gc->regs + ALTERA_GPIO_EDGE_CAP) & + readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK)))) { + writel(status, mm_gc->regs + ALTERA_GPIO_EDGE_CAP); + for_each_set_bit(i, &status, mm_gc->gc.ngpio) { + generic_handle_irq(irq_find_mapping(irqdomain, i)); + } + } + + chained_irq_exit(chip, desc); +} + + +static void altera_gpio_irq_leveL_high_handler(unsigned int irq, + struct irq_desc *desc) +{ + struct altera_gpio_chip *altera_gc; + struct irq_chip *chip; + struct of_mm_gpio_chip *mm_gc; + struct irq_domain *irqdomain; + unsigned long status; + int i; + + altera_gc = irq_desc_get_handler_data(desc); + chip = irq_desc_get_chip(desc); + mm_gc = &altera_gc->mmchip; + irqdomain = altera_gc->mmchip.gc.irqdomain; + + chained_irq_enter(chip, desc); + + status = readl(mm_gc->regs + ALTERA_GPIO_DATA); + status &= readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + + for_each_set_bit(i, &status, mm_gc->gc.ngpio) { + generic_handle_irq(irq_find_mapping(irqdomain, i)); + } + chained_irq_exit(chip, desc); +} + +static int altera_gpio_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + int reg, ret; + struct altera_gpio_chip *altera_gc; + + altera_gc = devm_kzalloc(&pdev->dev, sizeof(*altera_gc), GFP_KERNEL); + if (!altera_gc) + return -ENOMEM; + + spin_lock_init(&altera_gc->gpio_lock); + + if (of_property_read_u32(node, "altr,ngpio", ®)) + /* By default assume maximum ngpio */ + altera_gc->mmchip.gc.ngpio = ALTERA_GPIO_MAX_NGPIO; + else + altera_gc->mmchip.gc.ngpio = reg; + + if (altera_gc->mmchip.gc.ngpio > ALTERA_GPIO_MAX_NGPIO) { + dev_warn(&pdev->dev, + "ngpio is greater than %d, defaulting to %d\n", + ALTERA_GPIO_MAX_NGPIO, ALTERA_GPIO_MAX_NGPIO); + altera_gc->mmchip.gc.ngpio = ALTERA_GPIO_MAX_NGPIO; + } + + altera_gc->mmchip.gc.direction_input = altera_gpio_direction_input; + altera_gc->mmchip.gc.direction_output = altera_gpio_direction_output; + altera_gc->mmchip.gc.get = altera_gpio_get; + altera_gc->mmchip.gc.set = altera_gpio_set; + altera_gc->mmchip.gc.owner = THIS_MODULE; + altera_gc->mmchip.gc.dev = &pdev->dev; + + ret = of_mm_gpiochip_add(node, &altera_gc->mmchip); + if (ret) { + dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n"); + return ret; + } + + platform_set_drvdata(pdev, altera_gc); + + altera_gc->mapped_irq = platform_get_irq(pdev, 0); + + if (altera_gc->mapped_irq < 0) + goto skip_irq; + + if (of_property_read_u32(node, "altr,interrupt-type", ®)) { + ret = -EINVAL; + dev_err(&pdev->dev, + "altr,interrupt-type value not set in device tree\n"); + goto teardown; + } + altera_gc->interrupt_trigger = reg; + + ret = gpiochip_irqchip_add(&altera_gc->mmchip.gc, &altera_irq_chip, 0, + handle_simple_irq, IRQ_TYPE_NONE); + + if (ret) { + dev_info(&pdev->dev, "could not add irqchip\n"); + return ret; + } + + gpiochip_set_chained_irqchip(&altera_gc->mmchip.gc, + &altera_irq_chip, + altera_gc->mapped_irq, + altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH ? + altera_gpio_irq_leveL_high_handler : + altera_gpio_irq_edge_handler); + +skip_irq: + return 0; +teardown: + pr_err("%s: registration failed with status %d\n", + node->full_name, ret); + + return ret; +} + +static int altera_gpio_remove(struct platform_device *pdev) +{ + struct altera_gpio_chip *altera_gc = platform_get_drvdata(pdev); + + gpiochip_remove(&altera_gc->mmchip.gc); + + return -EIO; +} + +static const struct of_device_id altera_gpio_of_match[] = { + { .compatible = "altr,pio-1.0", }, + {}, +}; +MODULE_DEVICE_TABLE(of, altera_gpio_of_match); + +static struct platform_driver altera_gpio_driver = { + .driver = { + .name = "altera_gpio", + .of_match_table = of_match_ptr(altera_gpio_of_match), + }, + .probe = altera_gpio_probe, + .remove = altera_gpio_remove, +}; + +static int __init altera_gpio_init(void) +{ + return platform_driver_register(&altera_gpio_driver); +} +subsys_initcall(altera_gpio_init); + +static void __exit altera_gpio_exit(void) +{ + platform_driver_unregister(&altera_gpio_driver); +} +module_exit(altera_gpio_exit); + +MODULE_AUTHOR("Tien Hock Loh <thloh@altera.com>"); +MODULE_DESCRIPTION("Altera GPIO driver"); +MODULE_LICENSE("GPL"); |