diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/gpio/gpio-rcar.c | 605 |
1 files changed, 605 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c new file mode 100644 index 000000000..55cc61086 --- /dev/null +++ b/drivers/gpio/gpio-rcar.c @@ -0,0 +1,605 @@ +/* + * Renesas R-Car GPIO Support + * + * Copyright (C) 2014 Renesas Electronics Corporation + * Copyright (C) 2013 Magnus Damm + * + * 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 + * + * 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/err.h> +#include <linux/gpio/driver.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/spinlock.h> +#include <linux/slab.h> + +struct gpio_rcar_bank_info { + u32 iointsel; + u32 inoutsel; + u32 outdt; + u32 posneg; + u32 edglevel; + u32 bothedge; + u32 intmsk; +}; + +struct gpio_rcar_priv { + void __iomem *base; + spinlock_t lock; + struct platform_device *pdev; + struct gpio_chip gpio_chip; + struct irq_chip irq_chip; + unsigned int irq_parent; + atomic_t wakeup_path; + bool has_both_edge_trigger; + struct gpio_rcar_bank_info bank_info; +}; + +#define IOINTSEL 0x00 /* General IO/Interrupt Switching Register */ +#define INOUTSEL 0x04 /* General Input/Output Switching Register */ +#define OUTDT 0x08 /* General Output Register */ +#define INDT 0x0c /* General Input Register */ +#define INTDT 0x10 /* Interrupt Display Register */ +#define INTCLR 0x14 /* Interrupt Clear Register */ +#define INTMSK 0x18 /* Interrupt Mask Register */ +#define MSKCLR 0x1c /* Interrupt Mask Clear Register */ +#define POSNEG 0x20 /* Positive/Negative Logic Select Register */ +#define EDGLEVEL 0x24 /* Edge/level Select Register */ +#define FILONOFF 0x28 /* Chattering Prevention On/Off Register */ +#define BOTHEDGE 0x4c /* One Edge/Both Edge Select Register */ + +#define RCAR_MAX_GPIO_PER_BANK 32 + +static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs) +{ + return ioread32(p->base + offs); +} + +static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs, + u32 value) +{ + iowrite32(value, p->base + offs); +} + +static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs, + int bit, bool value) +{ + u32 tmp = gpio_rcar_read(p, offs); + + if (value) + tmp |= BIT(bit); + else + tmp &= ~BIT(bit); + + gpio_rcar_write(p, offs, tmp); +} + +static void gpio_rcar_irq_disable(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct gpio_rcar_priv *p = gpiochip_get_data(gc); + + gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d))); +} + +static void gpio_rcar_irq_enable(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct gpio_rcar_priv *p = gpiochip_get_data(gc); + + gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d))); +} + +static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p, + unsigned int hwirq, + bool active_high_rising_edge, + bool level_trigger, + bool both) +{ + unsigned long flags; + + /* follow steps in the GPIO documentation for + * "Setting Edge-Sensitive Interrupt Input Mode" and + * "Setting Level-Sensitive Interrupt Input Mode" + */ + + spin_lock_irqsave(&p->lock, flags); + + /* Configure postive or negative logic in POSNEG */ + gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge); + + /* Configure edge or level trigger in EDGLEVEL */ + gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger); + + /* Select one edge or both edges in BOTHEDGE */ + if (p->has_both_edge_trigger) + gpio_rcar_modify_bit(p, BOTHEDGE, hwirq, both); + + /* Select "Interrupt Input Mode" in IOINTSEL */ + gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true); + + /* Write INTCLR in case of edge trigger */ + if (!level_trigger) + gpio_rcar_write(p, INTCLR, BIT(hwirq)); + + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct gpio_rcar_priv *p = gpiochip_get_data(gc); + unsigned int hwirq = irqd_to_hwirq(d); + + dev_dbg(&p->pdev->dev, "sense irq = %d, type = %d\n", hwirq, type); + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_LEVEL_HIGH: + gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true, + false); + break; + case IRQ_TYPE_LEVEL_LOW: + gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true, + false); + break; + case IRQ_TYPE_EDGE_RISING: + gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false, + false); + break; + case IRQ_TYPE_EDGE_FALLING: + gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false, + false); + break; + case IRQ_TYPE_EDGE_BOTH: + if (!p->has_both_edge_trigger) + return -EINVAL; + gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false, + true); + break; + default: + return -EINVAL; + } + return 0; +} + +static int gpio_rcar_irq_set_wake(struct irq_data *d, unsigned int on) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct gpio_rcar_priv *p = gpiochip_get_data(gc); + int error; + + if (p->irq_parent) { + error = irq_set_irq_wake(p->irq_parent, on); + if (error) { + dev_dbg(&p->pdev->dev, + "irq %u doesn't support irq_set_wake\n", + p->irq_parent); + p->irq_parent = 0; + } + } + + if (on) + atomic_inc(&p->wakeup_path); + else + atomic_dec(&p->wakeup_path); + + return 0; +} + +static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id) +{ + struct gpio_rcar_priv *p = dev_id; + u32 pending; + unsigned int offset, irqs_handled = 0; + + while ((pending = gpio_rcar_read(p, INTDT) & + gpio_rcar_read(p, INTMSK))) { + offset = __ffs(pending); + gpio_rcar_write(p, INTCLR, BIT(offset)); + generic_handle_irq(irq_find_mapping(p->gpio_chip.irq.domain, + offset)); + irqs_handled++; + } + + return irqs_handled ? IRQ_HANDLED : IRQ_NONE; +} + +static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip, + unsigned int gpio, + bool output) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + unsigned long flags; + + /* follow steps in the GPIO documentation for + * "Setting General Output Mode" and + * "Setting General Input Mode" + */ + + spin_lock_irqsave(&p->lock, flags); + + /* Configure postive logic in POSNEG */ + gpio_rcar_modify_bit(p, POSNEG, gpio, false); + + /* Select "General Input/Output Mode" in IOINTSEL */ + gpio_rcar_modify_bit(p, IOINTSEL, gpio, false); + + /* Select Input Mode or Output Mode in INOUTSEL */ + gpio_rcar_modify_bit(p, INOUTSEL, gpio, output); + + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + int error; + + error = pm_runtime_get_sync(&p->pdev->dev); + if (error < 0) + return error; + + error = pinctrl_gpio_request(chip->base + offset); + if (error) + pm_runtime_put(&p->pdev->dev); + + return error; +} + +static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + + pinctrl_gpio_free(chip->base + offset); + + /* + * Set the GPIO as an input to ensure that the next GPIO request won't + * drive the GPIO pin as an output. + */ + gpio_rcar_config_general_input_output_mode(chip, offset, false); + + pm_runtime_put(&p->pdev->dev); +} + +static int gpio_rcar_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + + return !(gpio_rcar_read(p, INOUTSEL) & BIT(offset)); +} + +static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset) +{ + gpio_rcar_config_general_input_output_mode(chip, offset, false); + return 0; +} + +static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset) +{ + u32 bit = BIT(offset); + + /* testing on r8a7790 shows that INDT does not show correct pin state + * when configured as output, so use OUTDT in case of output pins */ + if (gpio_rcar_read(gpiochip_get_data(chip), INOUTSEL) & bit) + return !!(gpio_rcar_read(gpiochip_get_data(chip), OUTDT) & bit); + else + return !!(gpio_rcar_read(gpiochip_get_data(chip), INDT) & bit); +} + +static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + unsigned long flags; + + spin_lock_irqsave(&p->lock, flags); + gpio_rcar_modify_bit(p, OUTDT, offset, value); + spin_unlock_irqrestore(&p->lock, flags); +} + +static void gpio_rcar_set_multiple(struct gpio_chip *chip, unsigned long *mask, + unsigned long *bits) +{ + struct gpio_rcar_priv *p = gpiochip_get_data(chip); + unsigned long flags; + u32 val, bankmask; + + bankmask = mask[0] & GENMASK(chip->ngpio - 1, 0); + if (!bankmask) + return; + + spin_lock_irqsave(&p->lock, flags); + val = gpio_rcar_read(p, OUTDT); + val &= ~bankmask; + val |= (bankmask & bits[0]); + gpio_rcar_write(p, OUTDT, val); + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset, + int value) +{ + /* write GPIO value to output before selecting output mode of pin */ + gpio_rcar_set(chip, offset, value); + gpio_rcar_config_general_input_output_mode(chip, offset, true); + return 0; +} + +struct gpio_rcar_info { + bool has_both_edge_trigger; +}; + +static const struct gpio_rcar_info gpio_rcar_info_gen1 = { + .has_both_edge_trigger = false, +}; + +static const struct gpio_rcar_info gpio_rcar_info_gen2 = { + .has_both_edge_trigger = true, +}; + +static const struct of_device_id gpio_rcar_of_table[] = { + { + .compatible = "renesas,gpio-r8a7743", + /* RZ/G1 GPIO is identical to R-Car Gen2. */ + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7790", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7791", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7792", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7793", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7794", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7795", + /* Gen3 GPIO is identical to Gen2. */ + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-r8a7796", + /* Gen3 GPIO is identical to Gen2. */ + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,rcar-gen1-gpio", + .data = &gpio_rcar_info_gen1, + }, { + .compatible = "renesas,rcar-gen2-gpio", + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,rcar-gen3-gpio", + /* Gen3 GPIO is identical to Gen2. */ + .data = &gpio_rcar_info_gen2, + }, { + .compatible = "renesas,gpio-rcar", + .data = &gpio_rcar_info_gen1, + }, { + /* Terminator */ + }, +}; + +MODULE_DEVICE_TABLE(of, gpio_rcar_of_table); + +static int gpio_rcar_parse_dt(struct gpio_rcar_priv *p, unsigned int *npins) +{ + struct device_node *np = p->pdev->dev.of_node; + const struct gpio_rcar_info *info; + struct of_phandle_args args; + int ret; + + info = of_device_get_match_data(&p->pdev->dev); + + ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args); + *npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK; + p->has_both_edge_trigger = info->has_both_edge_trigger; + + if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) { + dev_warn(&p->pdev->dev, + "Invalid number of gpio lines %u, using %u\n", *npins, + RCAR_MAX_GPIO_PER_BANK); + *npins = RCAR_MAX_GPIO_PER_BANK; + } + + return 0; +} + +static int gpio_rcar_probe(struct platform_device *pdev) +{ + struct gpio_rcar_priv *p; + struct resource *io, *irq; + struct gpio_chip *gpio_chip; + struct irq_chip *irq_chip; + struct device *dev = &pdev->dev; + const char *name = dev_name(dev); + unsigned int npins; + int ret; + + p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); + if (!p) + return -ENOMEM; + + p->pdev = pdev; + spin_lock_init(&p->lock); + + /* Get device configuration from DT node */ + ret = gpio_rcar_parse_dt(p, &npins); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, p); + + pm_runtime_enable(dev); + + irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!irq) { + dev_err(dev, "missing IRQ\n"); + ret = -EINVAL; + goto err0; + } + + io = platform_get_resource(pdev, IORESOURCE_MEM, 0); + p->base = devm_ioremap_resource(dev, io); + if (IS_ERR(p->base)) { + ret = PTR_ERR(p->base); + goto err0; + } + + gpio_chip = &p->gpio_chip; + gpio_chip->request = gpio_rcar_request; + gpio_chip->free = gpio_rcar_free; + gpio_chip->get_direction = gpio_rcar_get_direction; + gpio_chip->direction_input = gpio_rcar_direction_input; + gpio_chip->get = gpio_rcar_get; + gpio_chip->direction_output = gpio_rcar_direction_output; + gpio_chip->set = gpio_rcar_set; + gpio_chip->set_multiple = gpio_rcar_set_multiple; + gpio_chip->label = name; + gpio_chip->parent = dev; + gpio_chip->owner = THIS_MODULE; + gpio_chip->base = -1; + gpio_chip->ngpio = npins; + + irq_chip = &p->irq_chip; + irq_chip->name = name; + irq_chip->parent_device = dev; + irq_chip->irq_mask = gpio_rcar_irq_disable; + irq_chip->irq_unmask = gpio_rcar_irq_enable; + irq_chip->irq_set_type = gpio_rcar_irq_set_type; + irq_chip->irq_set_wake = gpio_rcar_irq_set_wake; + irq_chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND; + + ret = gpiochip_add_data(gpio_chip, p); + if (ret) { + dev_err(dev, "failed to add GPIO controller\n"); + goto err0; + } + + ret = gpiochip_irqchip_add(gpio_chip, irq_chip, 0, handle_level_irq, + IRQ_TYPE_NONE); + if (ret) { + dev_err(dev, "cannot add irqchip\n"); + goto err1; + } + + p->irq_parent = irq->start; + if (devm_request_irq(dev, irq->start, gpio_rcar_irq_handler, + IRQF_SHARED, name, p)) { + dev_err(dev, "failed to request IRQ\n"); + ret = -ENOENT; + goto err1; + } + + dev_info(dev, "driving %d GPIOs\n", npins); + + return 0; + +err1: + gpiochip_remove(gpio_chip); +err0: + pm_runtime_disable(dev); + return ret; +} + +static int gpio_rcar_remove(struct platform_device *pdev) +{ + struct gpio_rcar_priv *p = platform_get_drvdata(pdev); + + gpiochip_remove(&p->gpio_chip); + + pm_runtime_disable(&pdev->dev); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int gpio_rcar_suspend(struct device *dev) +{ + struct gpio_rcar_priv *p = dev_get_drvdata(dev); + + p->bank_info.iointsel = gpio_rcar_read(p, IOINTSEL); + p->bank_info.inoutsel = gpio_rcar_read(p, INOUTSEL); + p->bank_info.outdt = gpio_rcar_read(p, OUTDT); + p->bank_info.intmsk = gpio_rcar_read(p, INTMSK); + p->bank_info.posneg = gpio_rcar_read(p, POSNEG); + p->bank_info.edglevel = gpio_rcar_read(p, EDGLEVEL); + if (p->has_both_edge_trigger) + p->bank_info.bothedge = gpio_rcar_read(p, BOTHEDGE); + + if (atomic_read(&p->wakeup_path)) + device_set_wakeup_path(dev); + + return 0; +} + +static int gpio_rcar_resume(struct device *dev) +{ + struct gpio_rcar_priv *p = dev_get_drvdata(dev); + unsigned int offset; + u32 mask; + + for (offset = 0; offset < p->gpio_chip.ngpio; offset++) { + mask = BIT(offset); + /* I/O pin */ + if (!(p->bank_info.iointsel & mask)) { + if (p->bank_info.inoutsel & mask) + gpio_rcar_direction_output( + &p->gpio_chip, offset, + !!(p->bank_info.outdt & mask)); + else + gpio_rcar_direction_input(&p->gpio_chip, + offset); + } else { + /* Interrupt pin */ + gpio_rcar_config_interrupt_input_mode( + p, + offset, + !(p->bank_info.posneg & mask), + !(p->bank_info.edglevel & mask), + !!(p->bank_info.bothedge & mask)); + + if (p->bank_info.intmsk & mask) + gpio_rcar_write(p, MSKCLR, mask); + } + } + + return 0; +} +#endif /* CONFIG_PM_SLEEP*/ + +static SIMPLE_DEV_PM_OPS(gpio_rcar_pm_ops, gpio_rcar_suspend, gpio_rcar_resume); + +static struct platform_driver gpio_rcar_device_driver = { + .probe = gpio_rcar_probe, + .remove = gpio_rcar_remove, + .driver = { + .name = "gpio_rcar", + .pm = &gpio_rcar_pm_ops, + .of_match_table = of_match_ptr(gpio_rcar_of_table), + } +}; + +module_platform_driver(gpio_rcar_device_driver); + +MODULE_AUTHOR("Magnus Damm"); +MODULE_DESCRIPTION("Renesas R-Car GPIO Driver"); +MODULE_LICENSE("GPL v2"); |