diff options
Diffstat (limited to 'drivers/bcma/driver_gpio.c')
| -rw-r--r-- | drivers/bcma/driver_gpio.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/drivers/bcma/driver_gpio.c b/drivers/bcma/driver_gpio.c new file mode 100644 index 00000000000..d7f81ad56b8 --- /dev/null +++ b/drivers/bcma/driver_gpio.c @@ -0,0 +1,254 @@ +/* + * 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.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/export.h> +#include <linux/bcma/bcma.h> + +#include "bcma_private.h" + +static inline struct bcma_drv_cc *bcma_gpio_get_cc(struct gpio_chip *chip) +{ + return container_of(chip, struct bcma_drv_cc, gpio); +} + +static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(chip); + + /* clear pullup */ + bcma_chipco_gpio_pullup(cc, 1 << gpio, 0); +} + +#if IS_BUILTIN(CONFIG_BCMA_HOST_SOC) +static int bcma_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) +{ + struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip); + + if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) + return irq_find_mapping(cc->irq_domain, gpio); + else + return -EINVAL; +} + +static void bcma_gpio_irq_unmask(struct irq_data *d) +{ + struct bcma_drv_cc *cc = irq_data_get_irq_chip_data(d); + 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 bcma_drv_cc *cc = irq_data_get_irq_chip_data(d); + 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; + 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, cc->gpio.ngpio) + generic_handle_irq(bcma_gpio_to_irq(&cc->gpio, gpio)); + bcma_chipco_gpio_polarity(cc, irqs, val & irqs); + + return IRQ_HANDLED; +} + +static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc) +{ + struct gpio_chip *chip = &cc->gpio; + int gpio, hwirq, err; + + if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC) + return 0; + + cc->irq_domain = irq_domain_add_linear(NULL, chip->ngpio, + &irq_domain_simple_ops, cc); + if (!cc->irq_domain) { + err = -ENODEV; + goto err_irq_domain; + } + for (gpio = 0; gpio < chip->ngpio; gpio++) { + int irq = irq_create_mapping(cc->irq_domain, gpio); + + irq_set_chip_data(irq, cc); + irq_set_chip_and_handler(irq, &bcma_gpio_irq_chip, + handle_simple_irq); + } + + hwirq = bcma_core_irq(cc->core); + err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio", + cc); + if (err) + goto err_req_irq; + + bcma_chipco_gpio_intmask(cc, ~0, 0); + bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO); + + return 0; + +err_req_irq: + for (gpio = 0; gpio < chip->ngpio; gpio++) { + int irq = irq_find_mapping(cc->irq_domain, gpio); + + irq_dispose_mapping(irq); + } + irq_domain_remove(cc->irq_domain); +err_irq_domain: + return err; +} + +static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc) +{ + struct gpio_chip *chip = &cc->gpio; + int gpio; + + 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), cc); + for (gpio = 0; gpio < chip->ngpio; gpio++) { + int irq = irq_find_mapping(cc->irq_domain, gpio); + + irq_dispose_mapping(irq); + } + irq_domain_remove(cc->irq_domain); +} +#else +static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc) +{ + return 0; +} + +static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc) +{ +} +#endif + +int bcma_gpio_init(struct bcma_drv_cc *cc) +{ + 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; +#if IS_BUILTIN(CONFIG_BCMA_HOST_SOC) + chip->to_irq = bcma_gpio_to_irq; +#endif + switch (cc->core->bus->chipinfo.id) { + case BCMA_CHIP_ID_BCM5357: + chip->ngpio = 32; + break; + default: + chip->ngpio = 16; + } + + /* There is just one SoC in one device and its GPIO addresses should be + * deterministic to address them more easily. The other buses could get + * a random base number. */ + if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC) + chip->base = 0; + else + chip->base = -1; + + err = bcma_gpio_irq_domain_init(cc); + if (err) + return err; + + err = gpiochip_add(chip); + if (err) { + bcma_gpio_irq_domain_exit(cc); + return err; + } + + return 0; +} + +int bcma_gpio_unregister(struct bcma_drv_cc *cc) +{ + bcma_gpio_irq_domain_exit(cc); + return gpiochip_remove(&cc->gpio); +} |