diff options
Diffstat (limited to 'drivers/bcma/driver_gpio.c')
| -rw-r--r-- | drivers/bcma/driver_gpio.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/drivers/bcma/driver_gpio.c b/drivers/bcma/driver_gpio.c new file mode 100644 index 0000000..5a08b4c --- /dev/null +++ b/drivers/bcma/driver_gpio.c @@ -0,0 +1,237 @@ +/* + * Broadcom specific AMBA + * GPIO driver + * + * Copyright 2011, Broadcom Corporation + * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de> + * + * Licensed under the GNU/GPL. See COPYING for details. + */ + +#include <linux/gpio/driver.h> +#include <linux/interrupt.h> +#include <linux/export.h> +#include <linux/bcma/bcma.h> + +#include "bcma_private.h" + +#define BCMA_GPIO_MAX_PINS 32 + +static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + return !!bcma_chipco_gpio_in(cc, 1 << gpio); +} + +static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio, + int value) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); +} + +static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + bcma_chipco_gpio_outen(cc, 1 << gpio, 0); + return 0; +} + +static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, + int value) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio); + bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0); + return 0; +} + +static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + bcma_chipco_gpio_control(cc, 1 << gpio, 0); + /* clear pulldown */ + bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0); + /* Set pullup */ + bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio); + + return 0; +} + +static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = gpiochip_get_data(chip); + + /* clear pullup */ + bcma_chipco_gpio_pullup(cc, 1 << gpio, 0); +} + +#if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X) + +static void bcma_gpio_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct bcma_drv_cc *cc = gpiochip_get_data(gc); + int gpio = irqd_to_hwirq(d); + u32 val = bcma_chipco_gpio_in(cc, BIT(gpio)); + + bcma_chipco_gpio_polarity(cc, BIT(gpio), val); + bcma_chipco_gpio_intmask(cc, BIT(gpio), BIT(gpio)); +} + +static void bcma_gpio_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct bcma_drv_cc *cc = gpiochip_get_data(gc); + int gpio = irqd_to_hwirq(d); + + bcma_chipco_gpio_intmask(cc, BIT(gpio), 0); +} + +static struct irq_chip bcma_gpio_irq_chip = { + .name = "BCMA-GPIO", + .irq_mask = bcma_gpio_irq_mask, + .irq_unmask = bcma_gpio_irq_unmask, +}; + +static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id) +{ + struct bcma_drv_cc *cc = dev_id; + struct gpio_chip *gc = &cc->gpio; + u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN); + u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ); + u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL); + unsigned long irqs = (val ^ pol) & mask; + int gpio; + + if (!irqs) + return IRQ_NONE; + + for_each_set_bit(gpio, &irqs, gc->ngpio) + generic_handle_irq(irq_find_mapping(gc->irq.domain, gpio)); + bcma_chipco_gpio_polarity(cc, irqs, val & irqs); + + return IRQ_HANDLED; +} + +static int bcma_gpio_irq_init(struct bcma_drv_cc *cc) +{ + struct gpio_chip *chip = &cc->gpio; + int hwirq, err; + + if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) + return 0; + + hwirq = bcma_core_irq(cc->core, 0); + err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio", + cc); + if (err) + return err; + + bcma_chipco_gpio_intmask(cc, ~0, 0); + bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO); + + err = gpiochip_irqchip_add(chip, + &bcma_gpio_irq_chip, + 0, + handle_simple_irq, + IRQ_TYPE_NONE); + if (err) { + free_irq(hwirq, cc); + return err; + } + + return 0; +} + +static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc) +{ + if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) + return; + + bcma_cc_mask32(cc, BCMA_CC_IRQMASK, ~BCMA_CC_IRQ_GPIO); + free_irq(bcma_core_irq(cc->core, 0), cc); +} +#else +static int bcma_gpio_irq_init(struct bcma_drv_cc *cc) +{ + return 0; +} + +static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc) +{ +} +#endif + +int bcma_gpio_init(struct bcma_drv_cc *cc) +{ + struct bcma_bus *bus = cc->core->bus; + struct gpio_chip *chip = &cc->gpio; + int err; + + chip->label = "bcma_gpio"; + chip->owner = THIS_MODULE; + chip->request = bcma_gpio_request; + chip->free = bcma_gpio_free; + chip->get = bcma_gpio_get_value; + chip->set = bcma_gpio_set_value; + chip->direction_input = bcma_gpio_direction_input; + chip->direction_output = bcma_gpio_direction_output; + chip->owner = THIS_MODULE; +#if LINUX_VERSION_IS_GEQ(4,5,0) + chip->parent = bcma_bus_get_host_dev(bus); +#else + chip->dev = bcma_bus_get_host_dev(bus); +#endif /* LINUX_VERSION_IS_GEQ(4,5,0) */ +#if IS_BUILTIN(CONFIG_OF) + chip->of_node = cc->core->dev.of_node; +#endif + switch (bus->chipinfo.id) { + case BCMA_CHIP_ID_BCM4707: + case BCMA_CHIP_ID_BCM5357: + case BCMA_CHIP_ID_BCM53572: + case BCMA_CHIP_ID_BCM53573: + case BCMA_CHIP_ID_BCM47094: + chip->ngpio = 32; + break; + default: + chip->ngpio = 16; + } + + /* + * Register SoC GPIO devices with absolute GPIO pin base. + * On MIPS, we don't have Device Tree and we can't use relative (per chip) + * GPIO numbers. + * On some ARM devices, user space may want to access some system GPIO + * pins directly, which is easier to do with a predictable GPIO base. + */ + if (IS_BUILTIN(CONFIG_BCM47XX) || + cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) + chip->base = bus->num * BCMA_GPIO_MAX_PINS; + else + chip->base = -1; + + err = gpiochip_add_data(chip, cc); + if (err) + return err; + + err = bcma_gpio_irq_init(cc); + if (err) { + gpiochip_remove(chip); + return err; + } + + return 0; +} + +int bcma_gpio_unregister(struct bcma_drv_cc *cc) +{ + bcma_gpio_irq_exit(cc); + gpiochip_remove(&cc->gpio); + return 0; +} |