diff options
Diffstat (limited to 'drivers/pinctrl/bcm/pinctrl-bcm2835.c')
-rw-r--r-- | drivers/pinctrl/bcm/pinctrl-bcm2835.c | 1110 |
1 files changed, 1110 insertions, 0 deletions
diff --git a/drivers/pinctrl/bcm/pinctrl-bcm2835.c b/drivers/pinctrl/bcm/pinctrl-bcm2835.c new file mode 100644 index 000000000..1bd3c10ce --- /dev/null +++ b/drivers/pinctrl/bcm/pinctrl-bcm2835.c @@ -0,0 +1,1110 @@ +/* + * Driver for Broadcom BCM2835 GPIO unit (pinctrl + GPIO) + * + * Copyright (C) 2012 Chris Boot, Simon Arlott, Stephen Warren + * + * This driver is inspired by: + * pinctrl-nomadik.c, please see original file for copyright information + * pinctrl-tegra.c, please see original file for copyright information + * + * 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. + */ + +#include <linux/bitmap.h> +#include <linux/bug.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/driver.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqdesc.h> +#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pinctrl/machine.h> +#include <linux/pinctrl/pinconf.h> +#include <linux/pinctrl/pinctrl.h> +#include <linux/pinctrl/pinmux.h> +#include <linux/pinctrl/pinconf-generic.h> +#include <linux/platform_device.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <dt-bindings/pinctrl/bcm2835.h> + +#define MODULE_NAME "pinctrl-bcm2835" +#define BCM2835_NUM_GPIOS 54 +#define BCM2835_NUM_BANKS 2 +#define BCM2835_NUM_IRQS 3 + +#define BCM2835_PIN_BITMAP_SZ \ + DIV_ROUND_UP(BCM2835_NUM_GPIOS, sizeof(unsigned long) * 8) + +/* GPIO register offsets */ +#define GPFSEL0 0x0 /* Function Select */ +#define GPSET0 0x1c /* Pin Output Set */ +#define GPCLR0 0x28 /* Pin Output Clear */ +#define GPLEV0 0x34 /* Pin Level */ +#define GPEDS0 0x40 /* Pin Event Detect Status */ +#define GPREN0 0x4c /* Pin Rising Edge Detect Enable */ +#define GPFEN0 0x58 /* Pin Falling Edge Detect Enable */ +#define GPHEN0 0x64 /* Pin High Detect Enable */ +#define GPLEN0 0x70 /* Pin Low Detect Enable */ +#define GPAREN0 0x7c /* Pin Async Rising Edge Detect */ +#define GPAFEN0 0x88 /* Pin Async Falling Edge Detect */ +#define GPPUD 0x94 /* Pin Pull-up/down Enable */ +#define GPPUDCLK0 0x98 /* Pin Pull-up/down Enable Clock */ + +#define FSEL_REG(p) (GPFSEL0 + (((p) / 10) * 4)) +#define FSEL_SHIFT(p) (((p) % 10) * 3) +#define GPIO_REG_OFFSET(p) ((p) / 32) +#define GPIO_REG_SHIFT(p) ((p) % 32) + +/* argument: bcm2835_pinconf_pull */ +#define BCM2835_PINCONF_PARAM_PULL (PIN_CONFIG_END + 1) + +struct bcm2835_pinctrl { + struct device *dev; + void __iomem *base; + int irq[BCM2835_NUM_IRQS]; + + /* note: locking assumes each bank will have its own unsigned long */ + unsigned long enabled_irq_map[BCM2835_NUM_BANKS]; + unsigned int irq_type[BCM2835_NUM_GPIOS]; + + struct pinctrl_dev *pctl_dev; + struct gpio_chip gpio_chip; + struct pinctrl_gpio_range gpio_range; + + raw_spinlock_t irq_lock[BCM2835_NUM_BANKS]; +}; + +/* pins are just named GPIO0..GPIO53 */ +#define BCM2835_GPIO_PIN(a) PINCTRL_PIN(a, "gpio" #a) +static struct pinctrl_pin_desc bcm2835_gpio_pins[] = { + BCM2835_GPIO_PIN(0), + BCM2835_GPIO_PIN(1), + BCM2835_GPIO_PIN(2), + BCM2835_GPIO_PIN(3), + BCM2835_GPIO_PIN(4), + BCM2835_GPIO_PIN(5), + BCM2835_GPIO_PIN(6), + BCM2835_GPIO_PIN(7), + BCM2835_GPIO_PIN(8), + BCM2835_GPIO_PIN(9), + BCM2835_GPIO_PIN(10), + BCM2835_GPIO_PIN(11), + BCM2835_GPIO_PIN(12), + BCM2835_GPIO_PIN(13), + BCM2835_GPIO_PIN(14), + BCM2835_GPIO_PIN(15), + BCM2835_GPIO_PIN(16), + BCM2835_GPIO_PIN(17), + BCM2835_GPIO_PIN(18), + BCM2835_GPIO_PIN(19), + BCM2835_GPIO_PIN(20), + BCM2835_GPIO_PIN(21), + BCM2835_GPIO_PIN(22), + BCM2835_GPIO_PIN(23), + BCM2835_GPIO_PIN(24), + BCM2835_GPIO_PIN(25), + BCM2835_GPIO_PIN(26), + BCM2835_GPIO_PIN(27), + BCM2835_GPIO_PIN(28), + BCM2835_GPIO_PIN(29), + BCM2835_GPIO_PIN(30), + BCM2835_GPIO_PIN(31), + BCM2835_GPIO_PIN(32), + BCM2835_GPIO_PIN(33), + BCM2835_GPIO_PIN(34), + BCM2835_GPIO_PIN(35), + BCM2835_GPIO_PIN(36), + BCM2835_GPIO_PIN(37), + BCM2835_GPIO_PIN(38), + BCM2835_GPIO_PIN(39), + BCM2835_GPIO_PIN(40), + BCM2835_GPIO_PIN(41), + BCM2835_GPIO_PIN(42), + BCM2835_GPIO_PIN(43), + BCM2835_GPIO_PIN(44), + BCM2835_GPIO_PIN(45), + BCM2835_GPIO_PIN(46), + BCM2835_GPIO_PIN(47), + BCM2835_GPIO_PIN(48), + BCM2835_GPIO_PIN(49), + BCM2835_GPIO_PIN(50), + BCM2835_GPIO_PIN(51), + BCM2835_GPIO_PIN(52), + BCM2835_GPIO_PIN(53), +}; + +/* one pin per group */ +static const char * const bcm2835_gpio_groups[] = { + "gpio0", + "gpio1", + "gpio2", + "gpio3", + "gpio4", + "gpio5", + "gpio6", + "gpio7", + "gpio8", + "gpio9", + "gpio10", + "gpio11", + "gpio12", + "gpio13", + "gpio14", + "gpio15", + "gpio16", + "gpio17", + "gpio18", + "gpio19", + "gpio20", + "gpio21", + "gpio22", + "gpio23", + "gpio24", + "gpio25", + "gpio26", + "gpio27", + "gpio28", + "gpio29", + "gpio30", + "gpio31", + "gpio32", + "gpio33", + "gpio34", + "gpio35", + "gpio36", + "gpio37", + "gpio38", + "gpio39", + "gpio40", + "gpio41", + "gpio42", + "gpio43", + "gpio44", + "gpio45", + "gpio46", + "gpio47", + "gpio48", + "gpio49", + "gpio50", + "gpio51", + "gpio52", + "gpio53", +}; + +enum bcm2835_fsel { + BCM2835_FSEL_COUNT = 8, + BCM2835_FSEL_MASK = 0x7, +}; + +static const char * const bcm2835_functions[BCM2835_FSEL_COUNT] = { + [BCM2835_FSEL_GPIO_IN] = "gpio_in", + [BCM2835_FSEL_GPIO_OUT] = "gpio_out", + [BCM2835_FSEL_ALT0] = "alt0", + [BCM2835_FSEL_ALT1] = "alt1", + [BCM2835_FSEL_ALT2] = "alt2", + [BCM2835_FSEL_ALT3] = "alt3", + [BCM2835_FSEL_ALT4] = "alt4", + [BCM2835_FSEL_ALT5] = "alt5", +}; + +static const char * const irq_type_names[] = { + [IRQ_TYPE_NONE] = "none", + [IRQ_TYPE_EDGE_RISING] = "edge-rising", + [IRQ_TYPE_EDGE_FALLING] = "edge-falling", + [IRQ_TYPE_EDGE_BOTH] = "edge-both", + [IRQ_TYPE_LEVEL_HIGH] = "level-high", + [IRQ_TYPE_LEVEL_LOW] = "level-low", +}; + +static inline u32 bcm2835_gpio_rd(struct bcm2835_pinctrl *pc, unsigned reg) +{ + return readl(pc->base + reg); +} + +static inline void bcm2835_gpio_wr(struct bcm2835_pinctrl *pc, unsigned reg, + u32 val) +{ + writel(val, pc->base + reg); +} + +static inline int bcm2835_gpio_get_bit(struct bcm2835_pinctrl *pc, unsigned reg, + unsigned bit) +{ + reg += GPIO_REG_OFFSET(bit) * 4; + return (bcm2835_gpio_rd(pc, reg) >> GPIO_REG_SHIFT(bit)) & 1; +} + +/* note NOT a read/modify/write cycle */ +static inline void bcm2835_gpio_set_bit(struct bcm2835_pinctrl *pc, + unsigned reg, unsigned bit) +{ + reg += GPIO_REG_OFFSET(bit) * 4; + bcm2835_gpio_wr(pc, reg, BIT(GPIO_REG_SHIFT(bit))); +} + +static inline enum bcm2835_fsel bcm2835_pinctrl_fsel_get( + struct bcm2835_pinctrl *pc, unsigned pin) +{ + u32 val = bcm2835_gpio_rd(pc, FSEL_REG(pin)); + enum bcm2835_fsel status = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK; + + dev_dbg(pc->dev, "get %08x (%u => %s)\n", val, pin, + bcm2835_functions[status]); + + return status; +} + +static inline void bcm2835_pinctrl_fsel_set( + struct bcm2835_pinctrl *pc, unsigned pin, + enum bcm2835_fsel fsel) +{ + u32 val = bcm2835_gpio_rd(pc, FSEL_REG(pin)); + enum bcm2835_fsel cur = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK; + + dev_dbg(pc->dev, "read %08x (%u => %s)\n", val, pin, + bcm2835_functions[cur]); + + if (cur == fsel) + return; + + if (cur != BCM2835_FSEL_GPIO_IN && fsel != BCM2835_FSEL_GPIO_IN) { + /* always transition through GPIO_IN */ + val &= ~(BCM2835_FSEL_MASK << FSEL_SHIFT(pin)); + val |= BCM2835_FSEL_GPIO_IN << FSEL_SHIFT(pin); + + dev_dbg(pc->dev, "trans %08x (%u <= %s)\n", val, pin, + bcm2835_functions[BCM2835_FSEL_GPIO_IN]); + bcm2835_gpio_wr(pc, FSEL_REG(pin), val); + } + + val &= ~(BCM2835_FSEL_MASK << FSEL_SHIFT(pin)); + val |= fsel << FSEL_SHIFT(pin); + + dev_dbg(pc->dev, "write %08x (%u <= %s)\n", val, pin, + bcm2835_functions[fsel]); + bcm2835_gpio_wr(pc, FSEL_REG(pin), val); +} + +static int bcm2835_gpio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_gpio_direction_input(chip->base + offset); +} + +static int bcm2835_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + + return bcm2835_gpio_get_bit(pc, GPLEV0, offset); +} + +static int bcm2835_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + enum bcm2835_fsel fsel = bcm2835_pinctrl_fsel_get(pc, offset); + + /* Alternative function doesn't clearly provide a direction */ + if (fsel > BCM2835_FSEL_GPIO_OUT) + return -EINVAL; + + return (fsel == BCM2835_FSEL_GPIO_IN); +} + +static void bcm2835_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + + bcm2835_gpio_set_bit(pc, value ? GPSET0 : GPCLR0, offset); +} + +static int bcm2835_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + bcm2835_gpio_set(chip, offset, value); + return pinctrl_gpio_direction_output(chip->base + offset); +} + +static const struct gpio_chip bcm2835_gpio_chip = { + .label = MODULE_NAME, + .owner = THIS_MODULE, + .request = gpiochip_generic_request, + .free = gpiochip_generic_free, + .direction_input = bcm2835_gpio_direction_input, + .direction_output = bcm2835_gpio_direction_output, + .get_direction = bcm2835_gpio_get_direction, + .get = bcm2835_gpio_get, + .set = bcm2835_gpio_set, + .base = -1, + .ngpio = BCM2835_NUM_GPIOS, + .can_sleep = false, +}; + +static void bcm2835_gpio_irq_handle_bank(struct bcm2835_pinctrl *pc, + unsigned int bank, u32 mask) +{ + unsigned long events; + unsigned offset; + unsigned gpio; + + events = bcm2835_gpio_rd(pc, GPEDS0 + bank * 4); + events &= mask; + events &= pc->enabled_irq_map[bank]; + for_each_set_bit(offset, &events, 32) { + gpio = (32 * bank) + offset; + generic_handle_irq(irq_linear_revmap(pc->gpio_chip.irq.domain, + gpio)); + } +} + +static void bcm2835_gpio_irq_handler(struct irq_desc *desc) +{ + struct gpio_chip *chip = irq_desc_get_handler_data(desc); + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + struct irq_chip *host_chip = irq_desc_get_chip(desc); + int irq = irq_desc_get_irq(desc); + int group; + int i; + + for (i = 0; i < ARRAY_SIZE(pc->irq); i++) { + if (pc->irq[i] == irq) { + group = i; + break; + } + } + /* This should not happen, every IRQ has a bank */ + if (i == ARRAY_SIZE(pc->irq)) + BUG(); + + chained_irq_enter(host_chip, desc); + + switch (group) { + case 0: /* IRQ0 covers GPIOs 0-27 */ + bcm2835_gpio_irq_handle_bank(pc, 0, 0x0fffffff); + break; + case 1: /* IRQ1 covers GPIOs 28-45 */ + bcm2835_gpio_irq_handle_bank(pc, 0, 0xf0000000); + bcm2835_gpio_irq_handle_bank(pc, 1, 0x00003fff); + break; + case 2: /* IRQ2 covers GPIOs 46-53 */ + bcm2835_gpio_irq_handle_bank(pc, 1, 0x003fc000); + break; + } + + chained_irq_exit(host_chip, desc); +} + +static inline void __bcm2835_gpio_irq_config(struct bcm2835_pinctrl *pc, + unsigned reg, unsigned offset, bool enable) +{ + u32 value; + reg += GPIO_REG_OFFSET(offset) * 4; + value = bcm2835_gpio_rd(pc, reg); + if (enable) + value |= BIT(GPIO_REG_SHIFT(offset)); + else + value &= ~(BIT(GPIO_REG_SHIFT(offset))); + bcm2835_gpio_wr(pc, reg, value); +} + +/* fast path for IRQ handler */ +static void bcm2835_gpio_irq_config(struct bcm2835_pinctrl *pc, + unsigned offset, bool enable) +{ + switch (pc->irq_type[offset]) { + case IRQ_TYPE_EDGE_RISING: + __bcm2835_gpio_irq_config(pc, GPREN0, offset, enable); + break; + + case IRQ_TYPE_EDGE_FALLING: + __bcm2835_gpio_irq_config(pc, GPFEN0, offset, enable); + break; + + case IRQ_TYPE_EDGE_BOTH: + __bcm2835_gpio_irq_config(pc, GPREN0, offset, enable); + __bcm2835_gpio_irq_config(pc, GPFEN0, offset, enable); + break; + + case IRQ_TYPE_LEVEL_HIGH: + __bcm2835_gpio_irq_config(pc, GPHEN0, offset, enable); + break; + + case IRQ_TYPE_LEVEL_LOW: + __bcm2835_gpio_irq_config(pc, GPLEN0, offset, enable); + break; + } +} + +static void bcm2835_gpio_irq_enable(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + unsigned gpio = irqd_to_hwirq(data); + unsigned offset = GPIO_REG_SHIFT(gpio); + unsigned bank = GPIO_REG_OFFSET(gpio); + unsigned long flags; + + raw_spin_lock_irqsave(&pc->irq_lock[bank], flags); + set_bit(offset, &pc->enabled_irq_map[bank]); + bcm2835_gpio_irq_config(pc, gpio, true); + raw_spin_unlock_irqrestore(&pc->irq_lock[bank], flags); +} + +static void bcm2835_gpio_irq_disable(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + unsigned gpio = irqd_to_hwirq(data); + unsigned offset = GPIO_REG_SHIFT(gpio); + unsigned bank = GPIO_REG_OFFSET(gpio); + unsigned long flags; + + raw_spin_lock_irqsave(&pc->irq_lock[bank], flags); + bcm2835_gpio_irq_config(pc, gpio, false); + /* Clear events that were latched prior to clearing event sources */ + bcm2835_gpio_set_bit(pc, GPEDS0, gpio); + clear_bit(offset, &pc->enabled_irq_map[bank]); + raw_spin_unlock_irqrestore(&pc->irq_lock[bank], flags); +} + +static int __bcm2835_gpio_irq_set_type_disabled(struct bcm2835_pinctrl *pc, + unsigned offset, unsigned int type) +{ + switch (type) { + case IRQ_TYPE_NONE: + case IRQ_TYPE_EDGE_RISING: + case IRQ_TYPE_EDGE_FALLING: + case IRQ_TYPE_EDGE_BOTH: + case IRQ_TYPE_LEVEL_HIGH: + case IRQ_TYPE_LEVEL_LOW: + pc->irq_type[offset] = type; + break; + + default: + return -EINVAL; + } + return 0; +} + +/* slower path for reconfiguring IRQ type */ +static int __bcm2835_gpio_irq_set_type_enabled(struct bcm2835_pinctrl *pc, + unsigned offset, unsigned int type) +{ + switch (type) { + case IRQ_TYPE_NONE: + if (pc->irq_type[offset] != type) { + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + } + break; + + case IRQ_TYPE_EDGE_RISING: + if (pc->irq_type[offset] == IRQ_TYPE_EDGE_BOTH) { + /* RISING already enabled, disable FALLING */ + pc->irq_type[offset] = IRQ_TYPE_EDGE_FALLING; + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + } else if (pc->irq_type[offset] != type) { + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + bcm2835_gpio_irq_config(pc, offset, true); + } + break; + + case IRQ_TYPE_EDGE_FALLING: + if (pc->irq_type[offset] == IRQ_TYPE_EDGE_BOTH) { + /* FALLING already enabled, disable RISING */ + pc->irq_type[offset] = IRQ_TYPE_EDGE_RISING; + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + } else if (pc->irq_type[offset] != type) { + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + bcm2835_gpio_irq_config(pc, offset, true); + } + break; + + case IRQ_TYPE_EDGE_BOTH: + if (pc->irq_type[offset] == IRQ_TYPE_EDGE_RISING) { + /* RISING already enabled, enable FALLING too */ + pc->irq_type[offset] = IRQ_TYPE_EDGE_FALLING; + bcm2835_gpio_irq_config(pc, offset, true); + pc->irq_type[offset] = type; + } else if (pc->irq_type[offset] == IRQ_TYPE_EDGE_FALLING) { + /* FALLING already enabled, enable RISING too */ + pc->irq_type[offset] = IRQ_TYPE_EDGE_RISING; + bcm2835_gpio_irq_config(pc, offset, true); + pc->irq_type[offset] = type; + } else if (pc->irq_type[offset] != type) { + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + bcm2835_gpio_irq_config(pc, offset, true); + } + break; + + case IRQ_TYPE_LEVEL_HIGH: + case IRQ_TYPE_LEVEL_LOW: + if (pc->irq_type[offset] != type) { + bcm2835_gpio_irq_config(pc, offset, false); + pc->irq_type[offset] = type; + bcm2835_gpio_irq_config(pc, offset, true); + } + break; + + default: + return -EINVAL; + } + return 0; +} + +static int bcm2835_gpio_irq_set_type(struct irq_data *data, unsigned int type) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + unsigned gpio = irqd_to_hwirq(data); + unsigned offset = GPIO_REG_SHIFT(gpio); + unsigned bank = GPIO_REG_OFFSET(gpio); + unsigned long flags; + int ret; + + raw_spin_lock_irqsave(&pc->irq_lock[bank], flags); + + if (test_bit(offset, &pc->enabled_irq_map[bank])) + ret = __bcm2835_gpio_irq_set_type_enabled(pc, gpio, type); + else + ret = __bcm2835_gpio_irq_set_type_disabled(pc, gpio, type); + + if (type & IRQ_TYPE_EDGE_BOTH) + irq_set_handler_locked(data, handle_edge_irq); + else + irq_set_handler_locked(data, handle_level_irq); + + raw_spin_unlock_irqrestore(&pc->irq_lock[bank], flags); + + return ret; +} + +static void bcm2835_gpio_irq_ack(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct bcm2835_pinctrl *pc = gpiochip_get_data(chip); + unsigned gpio = irqd_to_hwirq(data); + + bcm2835_gpio_set_bit(pc, GPEDS0, gpio); +} + +static struct irq_chip bcm2835_gpio_irq_chip = { + .name = MODULE_NAME, + .irq_enable = bcm2835_gpio_irq_enable, + .irq_disable = bcm2835_gpio_irq_disable, + .irq_set_type = bcm2835_gpio_irq_set_type, + .irq_ack = bcm2835_gpio_irq_ack, + .irq_mask = bcm2835_gpio_irq_disable, + .irq_unmask = bcm2835_gpio_irq_enable, +}; + +static int bcm2835_pctl_get_groups_count(struct pinctrl_dev *pctldev) +{ + return ARRAY_SIZE(bcm2835_gpio_groups); +} + +static const char *bcm2835_pctl_get_group_name(struct pinctrl_dev *pctldev, + unsigned selector) +{ + return bcm2835_gpio_groups[selector]; +} + +static int bcm2835_pctl_get_group_pins(struct pinctrl_dev *pctldev, + unsigned selector, + const unsigned **pins, + unsigned *num_pins) +{ + *pins = &bcm2835_gpio_pins[selector].number; + *num_pins = 1; + + return 0; +} + +static void bcm2835_pctl_pin_dbg_show(struct pinctrl_dev *pctldev, + struct seq_file *s, + unsigned offset) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + struct gpio_chip *chip = &pc->gpio_chip; + enum bcm2835_fsel fsel = bcm2835_pinctrl_fsel_get(pc, offset); + const char *fname = bcm2835_functions[fsel]; + int value = bcm2835_gpio_get_bit(pc, GPLEV0, offset); + int irq = irq_find_mapping(chip->irq.domain, offset); + + seq_printf(s, "function %s in %s; irq %d (%s)", + fname, value ? "hi" : "lo", + irq, irq_type_names[pc->irq_type[offset]]); +} + +static void bcm2835_pctl_dt_free_map(struct pinctrl_dev *pctldev, + struct pinctrl_map *maps, unsigned num_maps) +{ + int i; + + for (i = 0; i < num_maps; i++) + if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN) + kfree(maps[i].data.configs.configs); + + kfree(maps); +} + +static int bcm2835_pctl_dt_node_to_map_func(struct bcm2835_pinctrl *pc, + struct device_node *np, u32 pin, u32 fnum, + struct pinctrl_map **maps) +{ + struct pinctrl_map *map = *maps; + + if (fnum >= ARRAY_SIZE(bcm2835_functions)) { + dev_err(pc->dev, "%pOF: invalid brcm,function %d\n", np, fnum); + return -EINVAL; + } + + map->type = PIN_MAP_TYPE_MUX_GROUP; + map->data.mux.group = bcm2835_gpio_groups[pin]; + map->data.mux.function = bcm2835_functions[fnum]; + (*maps)++; + + return 0; +} + +static int bcm2835_pctl_dt_node_to_map_pull(struct bcm2835_pinctrl *pc, + struct device_node *np, u32 pin, u32 pull, + struct pinctrl_map **maps) +{ + struct pinctrl_map *map = *maps; + unsigned long *configs; + + if (pull > 2) { + dev_err(pc->dev, "%pOF: invalid brcm,pull %d\n", np, pull); + return -EINVAL; + } + + configs = kzalloc(sizeof(*configs), GFP_KERNEL); + if (!configs) + return -ENOMEM; + configs[0] = pinconf_to_config_packed(BCM2835_PINCONF_PARAM_PULL, pull); + + map->type = PIN_MAP_TYPE_CONFIGS_PIN; + map->data.configs.group_or_pin = bcm2835_gpio_pins[pin].name; + map->data.configs.configs = configs; + map->data.configs.num_configs = 1; + (*maps)++; + + return 0; +} + +static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev *pctldev, + struct device_node *np, + struct pinctrl_map **map, unsigned int *num_maps) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + struct property *pins, *funcs, *pulls; + int num_pins, num_funcs, num_pulls, maps_per_pin; + struct pinctrl_map *maps, *cur_map; + int i, err; + u32 pin, func, pull; + + /* Check for generic binding in this node */ + err = pinconf_generic_dt_node_to_map_all(pctldev, np, map, num_maps); + if (err || *num_maps) + return err; + + /* Generic binding did not find anything continue with legacy parse */ + pins = of_find_property(np, "brcm,pins", NULL); + if (!pins) { + dev_err(pc->dev, "%pOF: missing brcm,pins property\n", np); + return -EINVAL; + } + + funcs = of_find_property(np, "brcm,function", NULL); + pulls = of_find_property(np, "brcm,pull", NULL); + + if (!funcs && !pulls) { + dev_err(pc->dev, + "%pOF: neither brcm,function nor brcm,pull specified\n", + np); + return -EINVAL; + } + + num_pins = pins->length / 4; + num_funcs = funcs ? (funcs->length / 4) : 0; + num_pulls = pulls ? (pulls->length / 4) : 0; + + if (num_funcs > 1 && num_funcs != num_pins) { + dev_err(pc->dev, + "%pOF: brcm,function must have 1 or %d entries\n", + np, num_pins); + return -EINVAL; + } + + if (num_pulls > 1 && num_pulls != num_pins) { + dev_err(pc->dev, + "%pOF: brcm,pull must have 1 or %d entries\n", + np, num_pins); + return -EINVAL; + } + + maps_per_pin = 0; + if (num_funcs) + maps_per_pin++; + if (num_pulls) + maps_per_pin++; + cur_map = maps = kcalloc(num_pins * maps_per_pin, sizeof(*maps), + GFP_KERNEL); + if (!maps) + return -ENOMEM; + + for (i = 0; i < num_pins; i++) { + err = of_property_read_u32_index(np, "brcm,pins", i, &pin); + if (err) + goto out; + if (pin >= ARRAY_SIZE(bcm2835_gpio_pins)) { + dev_err(pc->dev, "%pOF: invalid brcm,pins value %d\n", + np, pin); + err = -EINVAL; + goto out; + } + + if (num_funcs) { + err = of_property_read_u32_index(np, "brcm,function", + (num_funcs > 1) ? i : 0, &func); + if (err) + goto out; + err = bcm2835_pctl_dt_node_to_map_func(pc, np, pin, + func, &cur_map); + if (err) + goto out; + } + if (num_pulls) { + err = of_property_read_u32_index(np, "brcm,pull", + (num_pulls > 1) ? i : 0, &pull); + if (err) + goto out; + err = bcm2835_pctl_dt_node_to_map_pull(pc, np, pin, + pull, &cur_map); + if (err) + goto out; + } + } + + *map = maps; + *num_maps = num_pins * maps_per_pin; + + return 0; + +out: + bcm2835_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin); + return err; +} + +static const struct pinctrl_ops bcm2835_pctl_ops = { + .get_groups_count = bcm2835_pctl_get_groups_count, + .get_group_name = bcm2835_pctl_get_group_name, + .get_group_pins = bcm2835_pctl_get_group_pins, + .pin_dbg_show = bcm2835_pctl_pin_dbg_show, + .dt_node_to_map = bcm2835_pctl_dt_node_to_map, + .dt_free_map = bcm2835_pctl_dt_free_map, +}; + +static int bcm2835_pmx_free(struct pinctrl_dev *pctldev, + unsigned offset) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + /* disable by setting to GPIO_IN */ + bcm2835_pinctrl_fsel_set(pc, offset, BCM2835_FSEL_GPIO_IN); + return 0; +} + +static int bcm2835_pmx_get_functions_count(struct pinctrl_dev *pctldev) +{ + return BCM2835_FSEL_COUNT; +} + +static const char *bcm2835_pmx_get_function_name(struct pinctrl_dev *pctldev, + unsigned selector) +{ + return bcm2835_functions[selector]; +} + +static int bcm2835_pmx_get_function_groups(struct pinctrl_dev *pctldev, + unsigned selector, + const char * const **groups, + unsigned * const num_groups) +{ + /* every pin can do every function */ + *groups = bcm2835_gpio_groups; + *num_groups = ARRAY_SIZE(bcm2835_gpio_groups); + + return 0; +} + +static int bcm2835_pmx_set(struct pinctrl_dev *pctldev, + unsigned func_selector, + unsigned group_selector) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + bcm2835_pinctrl_fsel_set(pc, group_selector, func_selector); + + return 0; +} + +static void bcm2835_pmx_gpio_disable_free(struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned offset) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + /* disable by setting to GPIO_IN */ + bcm2835_pinctrl_fsel_set(pc, offset, BCM2835_FSEL_GPIO_IN); +} + +static int bcm2835_pmx_gpio_set_direction(struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned offset, + bool input) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + enum bcm2835_fsel fsel = input ? + BCM2835_FSEL_GPIO_IN : BCM2835_FSEL_GPIO_OUT; + + bcm2835_pinctrl_fsel_set(pc, offset, fsel); + + return 0; +} + +static const struct pinmux_ops bcm2835_pmx_ops = { + .free = bcm2835_pmx_free, + .get_functions_count = bcm2835_pmx_get_functions_count, + .get_function_name = bcm2835_pmx_get_function_name, + .get_function_groups = bcm2835_pmx_get_function_groups, + .set_mux = bcm2835_pmx_set, + .gpio_disable_free = bcm2835_pmx_gpio_disable_free, + .gpio_set_direction = bcm2835_pmx_gpio_set_direction, +}; + +static int bcm2835_pinconf_get(struct pinctrl_dev *pctldev, + unsigned pin, unsigned long *config) +{ + /* No way to read back config in HW */ + return -ENOTSUPP; +} + +static void bcm2835_pull_config_set(struct bcm2835_pinctrl *pc, + unsigned int pin, unsigned int arg) +{ + u32 off, bit; + + off = GPIO_REG_OFFSET(pin); + bit = GPIO_REG_SHIFT(pin); + + bcm2835_gpio_wr(pc, GPPUD, arg & 3); + /* + * BCM2835 datasheet say to wait 150 cycles, but not of what. + * But the VideoCore firmware delay for this operation + * based nearly on the same amount of VPU cycles and this clock + * runs at 250 MHz. + */ + udelay(1); + bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), BIT(bit)); + udelay(1); + bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), 0); +} + +static int bcm2835_pinconf_set(struct pinctrl_dev *pctldev, + unsigned int pin, unsigned long *configs, + unsigned int num_configs) +{ + struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + u32 param, arg; + int i; + + for (i = 0; i < num_configs; i++) { + param = pinconf_to_config_param(configs[i]); + arg = pinconf_to_config_argument(configs[i]); + + switch (param) { + /* Set legacy brcm,pull */ + case BCM2835_PINCONF_PARAM_PULL: + bcm2835_pull_config_set(pc, pin, arg); + break; + + /* Set pull generic bindings */ + case PIN_CONFIG_BIAS_DISABLE: + bcm2835_pull_config_set(pc, pin, BCM2835_PUD_OFF); + break; + + case PIN_CONFIG_BIAS_PULL_DOWN: + bcm2835_pull_config_set(pc, pin, BCM2835_PUD_DOWN); + break; + + case PIN_CONFIG_BIAS_PULL_UP: + bcm2835_pull_config_set(pc, pin, BCM2835_PUD_UP); + break; + + /* Set output-high or output-low */ + case PIN_CONFIG_OUTPUT: + bcm2835_gpio_set_bit(pc, arg ? GPSET0 : GPCLR0, pin); + break; + + default: + return -EINVAL; + + } /* switch param type */ + } /* for each config */ + + return 0; +} + +static const struct pinconf_ops bcm2835_pinconf_ops = { + .pin_config_get = bcm2835_pinconf_get, + .pin_config_set = bcm2835_pinconf_set, +}; + +static struct pinctrl_desc bcm2835_pinctrl_desc = { + .name = MODULE_NAME, + .pins = bcm2835_gpio_pins, + .npins = ARRAY_SIZE(bcm2835_gpio_pins), + .pctlops = &bcm2835_pctl_ops, + .pmxops = &bcm2835_pmx_ops, + .confops = &bcm2835_pinconf_ops, + .owner = THIS_MODULE, +}; + +static struct pinctrl_gpio_range bcm2835_pinctrl_gpio_range = { + .name = MODULE_NAME, + .npins = BCM2835_NUM_GPIOS, +}; + +static int bcm2835_pinctrl_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct bcm2835_pinctrl *pc; + struct resource iomem; + int err, i; + BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_pins) != BCM2835_NUM_GPIOS); + BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_groups) != BCM2835_NUM_GPIOS); + + pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + platform_set_drvdata(pdev, pc); + pc->dev = dev; + + err = of_address_to_resource(np, 0, &iomem); + if (err) { + dev_err(dev, "could not get IO memory\n"); + return err; + } + + pc->base = devm_ioremap_resource(dev, &iomem); + if (IS_ERR(pc->base)) + return PTR_ERR(pc->base); + + pc->gpio_chip = bcm2835_gpio_chip; + pc->gpio_chip.parent = dev; + pc->gpio_chip.of_node = np; + + for (i = 0; i < BCM2835_NUM_BANKS; i++) { + unsigned long events; + unsigned offset; + + /* clear event detection flags */ + bcm2835_gpio_wr(pc, GPREN0 + i * 4, 0); + bcm2835_gpio_wr(pc, GPFEN0 + i * 4, 0); + bcm2835_gpio_wr(pc, GPHEN0 + i * 4, 0); + bcm2835_gpio_wr(pc, GPLEN0 + i * 4, 0); + bcm2835_gpio_wr(pc, GPAREN0 + i * 4, 0); + bcm2835_gpio_wr(pc, GPAFEN0 + i * 4, 0); + + /* clear all the events */ + events = bcm2835_gpio_rd(pc, GPEDS0 + i * 4); + for_each_set_bit(offset, &events, 32) + bcm2835_gpio_wr(pc, GPEDS0 + i * 4, BIT(offset)); + + raw_spin_lock_init(&pc->irq_lock[i]); + } + + err = gpiochip_add_data(&pc->gpio_chip, pc); + if (err) { + dev_err(dev, "could not add GPIO chip\n"); + return err; + } + + err = gpiochip_irqchip_add(&pc->gpio_chip, &bcm2835_gpio_irq_chip, + 0, handle_level_irq, IRQ_TYPE_NONE); + if (err) { + dev_info(dev, "could not add irqchip\n"); + return err; + } + + for (i = 0; i < BCM2835_NUM_IRQS; i++) { + pc->irq[i] = irq_of_parse_and_map(np, i); + + if (pc->irq[i] == 0) + continue; + + /* + * Use the same handler for all groups: this is necessary + * since we use one gpiochip to cover all lines - the + * irq handler then needs to figure out which group and + * bank that was firing the IRQ and look up the per-group + * and bank data. + */ + gpiochip_set_chained_irqchip(&pc->gpio_chip, + &bcm2835_gpio_irq_chip, + pc->irq[i], + bcm2835_gpio_irq_handler); + } + + pc->pctl_dev = devm_pinctrl_register(dev, &bcm2835_pinctrl_desc, pc); + if (IS_ERR(pc->pctl_dev)) { + gpiochip_remove(&pc->gpio_chip); + return PTR_ERR(pc->pctl_dev); + } + + pc->gpio_range = bcm2835_pinctrl_gpio_range; + pc->gpio_range.base = pc->gpio_chip.base; + pc->gpio_range.gc = &pc->gpio_chip; + pinctrl_add_gpio_range(pc->pctl_dev, &pc->gpio_range); + + return 0; +} + +static const struct of_device_id bcm2835_pinctrl_match[] = { + { .compatible = "brcm,bcm2835-gpio" }, + {} +}; + +static struct platform_driver bcm2835_pinctrl_driver = { + .probe = bcm2835_pinctrl_probe, + .driver = { + .name = MODULE_NAME, + .of_match_table = bcm2835_pinctrl_match, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(bcm2835_pinctrl_driver); |