Acked-by: Christian Ruppert <christian.ruppert at alitech.com>
On 06.08.2018 17:12, Linus Walleij wrote:
> Instead of open coding logic for reading and writing GPIO lines,
> use the generic GPIO library. Also switch to using the spinlock
> from the generic GPIO to protect the registers.
>
> Cc: linux-snps-arc at lists.infradead.org
> Cc: Christian Ruppert <christian.ruppert at alitech.com>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
> ---
> drivers/gpio/Kconfig | 1 +
> drivers/gpio/gpio-tb10x.c | 96 ++++++++++++---------------------------
> 2 files changed, 31 insertions(+), 66 deletions(-)
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 7429b30e61b0..d351548d0257 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -480,6 +480,7 @@ config GPIO_SYSCON
>
> config GPIO_TB10X
> bool
> + select GPIO_GENERIC
> select GENERIC_IRQ_CHIP
> select OF_GPIO
>
> diff --git a/drivers/gpio/gpio-tb10x.c b/drivers/gpio/gpio-tb10x.c
> index 422b0ac5a9de..d5e5d19f4c0a 100644
> --- a/drivers/gpio/gpio-tb10x.c
> +++ b/drivers/gpio/gpio-tb10x.c
> @@ -45,14 +45,12 @@
>
>
> /**
> - * @spinlock: used for atomic read/modify/write of registers
> * @base: register base address
> * @domain: IRQ domain of GPIO generated interrupts managed by this controller
> * @irq: Interrupt line of parent interrupt controller
> * @gc: gpio_chip structure associated to this GPIO controller
> */
> struct tb10x_gpio {
> - spinlock_t spinlock;
> void __iomem *base;
> struct irq_domain *domain;
> int irq;
> @@ -76,60 +74,14 @@ static inline void tb10x_set_bits(struct tb10x_gpio *gpio, unsigned int offs,
> u32 r;
> unsigned long flags;
>
> - spin_lock_irqsave(&gpio->spinlock, flags);
> + spin_lock_irqsave(&gpio->gc.bgpio_lock, flags);
>
> r = tb10x_reg_read(gpio, offs);
> r = (r & ~mask) | (val & mask);
>
> tb10x_reg_write(gpio, offs, r);
>
> - spin_unlock_irqrestore(&gpio->spinlock, flags);
> -}
> -
> -static int tb10x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
> -{
> - struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(chip);
> - int mask = BIT(offset);
> - int val = TB10X_GPIO_DIR_IN << offset;
> -
> - tb10x_set_bits(tb10x_gpio, OFFSET_TO_REG_DDR, mask, val);
> -
> - return 0;
> -}
> -
> -static int tb10x_gpio_get(struct gpio_chip *chip, unsigned offset)
> -{
> - struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(chip);
> - int val;
> -
> - val = tb10x_reg_read(tb10x_gpio, OFFSET_TO_REG_DATA);
> -
> - if (val & BIT(offset))
> - return 1;
> - else
> - return 0;
> -}
> -
> -static void tb10x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
> -{
> - struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(chip);
> - int mask = BIT(offset);
> - int val = value << offset;
> -
> - tb10x_set_bits(tb10x_gpio, OFFSET_TO_REG_DATA, mask, val);
> -}
> -
> -static int tb10x_gpio_direction_out(struct gpio_chip *chip,
> - unsigned offset, int value)
> -{
> - struct tb10x_gpio *tb10x_gpio = gpiochip_get_data(chip);
> - int mask = BIT(offset);
> - int val = TB10X_GPIO_DIR_OUT << offset;
> -
> - tb10x_gpio_set(chip, offset, value);
> - tb10x_set_bits(tb10x_gpio, OFFSET_TO_REG_DDR, mask, val);
> -
> - return 0;
> + spin_unlock_irqrestore(&gpio->gc.bgpio_lock, flags);
> }
>
> static int tb10x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
> @@ -184,8 +136,6 @@ static int tb10x_gpio_probe(struct platform_device *pdev)
> if (tb10x_gpio == NULL)
> return -ENOMEM;
>
> - spin_lock_init(&tb10x_gpio->spinlock);
> -
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> tb10x_gpio->base = devm_ioremap_resource(dev, mem);
> if (IS_ERR(tb10x_gpio->base))
> @@ -196,20 +146,34 @@ static int tb10x_gpio_probe(struct platform_device *pdev)
> if (!tb10x_gpio->gc.label)
> return -ENOMEM;
>
> - tb10x_gpio->gc.parent = &pdev->dev;
> - tb10x_gpio->gc.owner = THIS_MODULE;
> - tb10x_gpio->gc.direction_input = tb10x_gpio_direction_in;
> - tb10x_gpio->gc.get = tb10x_gpio_get;
> - tb10x_gpio->gc.direction_output = tb10x_gpio_direction_out;
> - tb10x_gpio->gc.set = tb10x_gpio_set;
> - tb10x_gpio->gc.request = gpiochip_generic_request;
> - tb10x_gpio->gc.free = gpiochip_generic_free;
> - tb10x_gpio->gc.base = -1;
> - tb10x_gpio->gc.ngpio = ngpio;
> - tb10x_gpio->gc.can_sleep = false;
> -
> -
> - ret = devm_gpiochip_add_data(&pdev->dev, &tb10x_gpio->gc, tb10x_gpio);
> + /*
> + * Initialize generic GPIO with one single register for reading and setting
> + * the lines, no special set or clear registers and a data direction register
> + * wher 1 means "output".
> + */
> + ret = bgpio_init(&tb10x_gpio->gc, dev, 4,
> + tb10x_gpio->base + OFFSET_TO_REG_DATA,
> + NULL,
> + NULL,
> + tb10x_gpio->base + OFFSET_TO_REG_DDR,
> + NULL,
> + 0);
> + if (ret) {
> + dev_err(dev, "unable to init generic GPIO\n");
> + return ret;
> + }
> + tb10x_gpio->gc.base = -1;
> + tb10x_gpio->gc.parent = dev;
> + tb10x_gpio->gc.owner = THIS_MODULE;
> + /*
> + * ngpio is set by bgpio_init() but we override it, this .request()
> + * callback also overrides the one set up by generic GPIO.
> + */
> + tb10x_gpio->gc.ngpio = ngpio;
> + tb10x_gpio->gc.request = gpiochip_generic_request;
> + tb10x_gpio->gc.free = gpiochip_generic_free;
> +
> + ret = devm_gpiochip_add_data(dev, &tb10x_gpio->gc, tb10x_gpio);
> if (ret < 0) {
> dev_err(dev, "Could not add gpiochip.\n");
> return ret;
>
