diff options
Diffstat (limited to 'drivers/gpio/iproc_gpio.c')
-rw-r--r-- | drivers/gpio/iproc_gpio.c | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/drivers/gpio/iproc_gpio.c b/drivers/gpio/iproc_gpio.c new file mode 100644 index 0000000000..cc26a1306b --- /dev/null +++ b/drivers/gpio/iproc_gpio.c @@ -0,0 +1,290 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2020 Broadcom + */ + +#include <common.h> +#include <errno.h> +#include <asm/gpio.h> +#include <asm/io.h> +#include <dm.h> +#include <dm/device_compat.h> +#include <dm/devres.h> +#include <dm/pinctrl.h> + +/* + * There are five GPIO bank register. Each bank can configure max of 32 gpios. + * BANK0 - gpios 0 to 31 + * BANK1 - gpios 32 to 63 + * BANK2 - gpios 64 to 95 + * BANK3 - gpios 96 to 127 + * BANK4 - gpios 128 to 150 + * + * Offset difference between consecutive bank register is 0x200 + */ +#define NGPIO_PER_BANK 32 +#define GPIO_BANK_SIZE 0x200 +#define GPIO_BANK(pin) ((pin) / NGPIO_PER_BANK) +#define GPIO_SHIFT(pin) ((pin) % NGPIO_PER_BANK) +#define GPIO_REG(pin, reg) (GPIO_BANK_SIZE * GPIO_BANK(pin) + (reg)) + +/* device register offset */ +#define DATA_IN_OFFSET 0x00 +#define DATA_OUT_OFFSET 0x04 +#define OUT_EN_OFFSET 0x08 + +/** + * struct iproc_gpio_pctrl_map - gpio and pinctrl mapping + * @gpio_pin: start of gpio number in gpio-ranges + * @pctrl_pin: start of pinctrl number in gpio-ranges + * @npins: total number of pins in gpio-ranges + * @node: list node + */ +struct iproc_gpio_pctrl_map { + u32 gpio_pin; + u32 pctrl_pin; + u32 npins; + struct list_head node; +}; + +/** + * struct iproc_gpio_pctrl_map - gpio device instance + * @pinctrl_dev:pointer to pinctrl device + * @gpiomap: list node having mapping between gpio and pinctrl + * @base: I/O register base address of gpio device + * @name: gpio device name, ex GPIO0, GPIO1 + * @ngpios: total number of gpios + */ +struct iproc_gpio_platdata { + struct udevice *pinctrl_dev; + struct list_head gpiomap; + void __iomem *base; + char *name; + u32 ngpios; +}; + +/** + * iproc_gpio_set_bit - set or clear one bit in an iproc GPIO register. + * + * The bit relates to a GPIO pin. + * + * @plat: iproc GPIO device + * @reg: register offset + * @gpio: GPIO pin + * @set: set or clear + */ +static inline void iproc_gpio_set_bit(struct iproc_gpio_platdata *plat, + u32 reg, u32 gpio, bool set) +{ + u32 offset = GPIO_REG(gpio, reg); + u32 shift = GPIO_SHIFT(gpio); + + clrsetbits_le32(plat->base + offset, BIT(shift), + (set ? BIT(shift) : 0)); +} + +static inline bool iproc_gpio_get_bit(struct iproc_gpio_platdata *plat, + u32 reg, u32 gpio) +{ + u32 offset = GPIO_REG(gpio, reg); + u32 shift = GPIO_SHIFT(gpio); + + return readl(plat->base + offset) & BIT(shift); +} + +/** + * iproc_get_gpio_pctrl_mapping() - get associated pinctrl pin from gpio pin + * + * @plat: iproc GPIO device + * @gpio: GPIO pin + */ +static u32 iproc_get_pctrl_from_gpio(struct iproc_gpio_platdata *plat, u32 gpio) +{ + struct iproc_gpio_pctrl_map *range = NULL; + struct list_head *pos, *tmp; + u32 ret = 0; + + list_for_each_safe(pos, tmp, &plat->gpiomap) { + range = list_entry(pos, struct iproc_gpio_pctrl_map, node); + if (gpio == range->gpio_pin || + gpio < (range->gpio_pin + range->npins)) { + ret = range->pctrl_pin + (gpio - range->gpio_pin); + break; + } + } + + return ret; +} + +/** + * iproc_get_gpio_pctrl_mapping() - get mapping between gpio and pinctrl + * + * Read dt node "gpio-ranges" to get gpio and pinctrl mapping and store + * in private data structure to use it later while enabling gpio. + * + * @dev: pointer to GPIO device + * @return 0 on success and -ENOMEM on failure + */ +static int iproc_get_gpio_pctrl_mapping(struct udevice *dev) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + struct iproc_gpio_pctrl_map *range = NULL; + struct ofnode_phandle_args args; + int index = 0, ret; + + for (;; index++) { + ret = dev_read_phandle_with_args(dev, "gpio-ranges", + NULL, 3, index, &args); + if (ret) + break; + + range = devm_kzalloc(dev, sizeof(*range), GFP_KERNEL); + if (!range) + return -ENOMEM; + + range->gpio_pin = args.args[0]; + range->pctrl_pin = args.args[1]; + range->npins = args.args[2]; + list_add_tail(&range->node, &plat->gpiomap); + } + + return 0; +} + +static int iproc_gpio_request(struct udevice *dev, u32 gpio, const char *label) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + u32 pctrl; + + /* nothing to do if there is no corresponding pinctrl device */ + if (!plat->pinctrl_dev) + return 0; + + pctrl = iproc_get_pctrl_from_gpio(plat, gpio); + + return pinctrl_request(plat->pinctrl_dev, pctrl, 0); +} + +static int iproc_gpio_direction_input(struct udevice *dev, u32 gpio) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + + iproc_gpio_set_bit(plat, OUT_EN_OFFSET, gpio, false); + dev_dbg(dev, "gpio:%u set input\n", gpio); + + return 0; +} + +static int iproc_gpio_direction_output(struct udevice *dev, u32 gpio, int value) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + + iproc_gpio_set_bit(plat, OUT_EN_OFFSET, gpio, true); + iproc_gpio_set_bit(plat, DATA_OUT_OFFSET, gpio, value); + dev_dbg(dev, "gpio:%u set output, value:%d\n", gpio, value); + + return 0; +} + +static int iproc_gpio_get_value(struct udevice *dev, u32 gpio) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + int value; + + value = iproc_gpio_get_bit(plat, DATA_IN_OFFSET, gpio); + dev_dbg(dev, "gpio:%u get, value:%d\n", gpio, value); + + return value; +} + +static int iproc_gpio_set_value(struct udevice *dev, u32 gpio, int value) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + + if (iproc_gpio_get_bit(plat, OUT_EN_OFFSET, gpio)) + iproc_gpio_set_bit(plat, DATA_OUT_OFFSET, gpio, value); + + dev_dbg(dev, "gpio:%u set, value:%d\n", gpio, value); + return 0; +} + +static int iproc_gpio_get_function(struct udevice *dev, u32 gpio) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + + if (iproc_gpio_get_bit(plat, OUT_EN_OFFSET, gpio)) + return GPIOF_OUTPUT; + else + return GPIOF_INPUT; +} + +static int iproc_gpio_ofdata_to_platdata(struct udevice *dev) +{ + struct iproc_gpio_platdata *plat = dev_get_platdata(dev); + struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); + int ret; + char name[10]; + + plat->base = dev_read_addr_ptr(dev); + if (!plat->base) { + debug("%s: Failed to get base address\n", __func__); + return -EINVAL; + } + + ret = dev_read_u32(dev, "ngpios", &plat->ngpios); + if (ret < 0) { + dev_err(dev, "%s: Failed to get ngpios\n", __func__); + return ret; + } + + uclass_get_device_by_phandle(UCLASS_PINCTRL, dev, "gpio-ranges", + &plat->pinctrl_dev); + if (ret < 0) { + dev_err(dev, "%s: Failed to get pinctrl phandle\n", __func__); + return ret; + } + + INIT_LIST_HEAD(&plat->gpiomap); + ret = iproc_get_gpio_pctrl_mapping(dev); + if (ret < 0) { + dev_err(dev, "%s: Failed to get gpio to pctrl map ret(%d)\n", + __func__, ret); + return ret; + } + + snprintf(name, sizeof(name), "GPIO%d", dev->req_seq); + plat->name = strdup(name); + if (!plat->name) + return -ENOMEM; + + uc_priv->gpio_count = plat->ngpios; + uc_priv->bank_name = plat->name; + + dev_info(dev, ":bank name(%s) base %p, #gpios %d\n", + plat->name, plat->base, plat->ngpios); + + return 0; +} + +static const struct dm_gpio_ops iproc_gpio_ops = { + .request = iproc_gpio_request, + .direction_input = iproc_gpio_direction_input, + .direction_output = iproc_gpio_direction_output, + .get_value = iproc_gpio_get_value, + .set_value = iproc_gpio_set_value, + .get_function = iproc_gpio_get_function, +}; + +static const struct udevice_id iproc_gpio_ids[] = { + { .compatible = "brcm,iproc-gpio" }, + { } +}; + +U_BOOT_DRIVER(iproc_gpio) = { + .name = "iproc_gpio", + .id = UCLASS_GPIO, + .of_match = iproc_gpio_ids, + .ops = &iproc_gpio_ops, + .ofdata_to_platdata = iproc_gpio_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct iproc_gpio_platdata), +}; 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