diff options
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt | 5 | ||||
| -rw-r--r-- | drivers/gpio/gpio-aspeed-sgpio.c | 126 |
2 files changed, 87 insertions, 44 deletions
diff --git a/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt b/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt index d4d83916c09d..be329ea4794f 100644 --- a/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt +++ b/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt @@ -20,8 +20,9 @@ Required properties: - gpio-controller : Marks the device node as a GPIO controller - interrupts : Interrupt specifier, see interrupt-controller/interrupts.txt - interrupt-controller : Mark the GPIO controller as an interrupt-controller -- ngpios : number of GPIO lines, see gpio.txt - (should be multiple of 8, up to 80 pins) +- ngpios : number of *hardware* GPIO lines, see gpio.txt. This will expose + 2 software GPIOs per hardware GPIO: one for hardware input, one for hardware + output. Up to 80 pins, must be a multiple of 8. - clocks : A phandle to the APB clock for SGPM clock division - bus-frequency : SGPM CLK frequency diff --git a/drivers/gpio/gpio-aspeed-sgpio.c b/drivers/gpio/gpio-aspeed-sgpio.c index d16645c1d8d9..5d678dbf1a62 100644 --- a/drivers/gpio/gpio-aspeed-sgpio.c +++ b/drivers/gpio/gpio-aspeed-sgpio.c @@ -17,7 +17,17 @@ #include <linux/spinlock.h> #include <linux/string.h> -#define MAX_NR_SGPIO 80 +/* + * MAX_NR_HW_GPIO represents the number of actual hardware-supported GPIOs (ie, + * slots within the clocked serial GPIO data). Since each HW GPIO is both an + * input and an output, we provide MAX_NR_HW_GPIO * 2 lines on our gpiochip + * device. + * + * We use SGPIO_OUTPUT_OFFSET to define the split between the inputs and + * outputs; the inputs start at line 0, the outputs start at OUTPUT_OFFSET. + */ +#define MAX_NR_HW_SGPIO 80 +#define SGPIO_OUTPUT_OFFSET MAX_NR_HW_SGPIO #define ASPEED_SGPIO_CTRL 0x54 @@ -30,8 +40,8 @@ struct aspeed_sgpio { struct clk *pclk; spinlock_t lock; void __iomem *base; - uint32_t dir_in[3]; int irq; + int n_sgpio; }; struct aspeed_sgpio_bank { @@ -111,31 +121,69 @@ static void __iomem *bank_reg(struct aspeed_sgpio *gpio, } } -#define GPIO_BANK(x) ((x) >> 5) -#define GPIO_OFFSET(x) ((x) & 0x1f) +#define GPIO_BANK(x) ((x % SGPIO_OUTPUT_OFFSET) >> 5) +#define GPIO_OFFSET(x) ((x % SGPIO_OUTPUT_OFFSET) & 0x1f) #define GPIO_BIT(x) BIT(GPIO_OFFSET(x)) static const struct aspeed_sgpio_bank *to_bank(unsigned int offset) { - unsigned int bank = GPIO_BANK(offset); + unsigned int bank; + + bank = GPIO_BANK(offset); WARN_ON(bank >= ARRAY_SIZE(aspeed_sgpio_banks)); return &aspeed_sgpio_banks[bank]; } +static int aspeed_sgpio_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, unsigned int ngpios) +{ + struct aspeed_sgpio *sgpio = gpiochip_get_data(gc); + int n = sgpio->n_sgpio; + int c = SGPIO_OUTPUT_OFFSET - n; + + WARN_ON(ngpios < MAX_NR_HW_SGPIO * 2); + + /* input GPIOs in the lower range */ + bitmap_set(valid_mask, 0, n); + bitmap_clear(valid_mask, n, c); + + /* output GPIOS above SGPIO_OUTPUT_OFFSET */ + bitmap_set(valid_mask, SGPIO_OUTPUT_OFFSET, n); + bitmap_clear(valid_mask, SGPIO_OUTPUT_OFFSET + n, c); + + return 0; +} + +static void aspeed_sgpio_irq_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, unsigned int ngpios) +{ + struct aspeed_sgpio *sgpio = gpiochip_get_data(gc); + int n = sgpio->n_sgpio; + + WARN_ON(ngpios < MAX_NR_HW_SGPIO * 2); + + /* input GPIOs in the lower range */ + bitmap_set(valid_mask, 0, n); + bitmap_clear(valid_mask, n, ngpios - n); +} + +static bool aspeed_sgpio_is_input(unsigned int offset) +{ + return offset < SGPIO_OUTPUT_OFFSET; +} + static int aspeed_sgpio_get(struct gpio_chip *gc, unsigned int offset) { struct aspeed_sgpio *gpio = gpiochip_get_data(gc); const struct aspeed_sgpio_bank *bank = to_bank(offset); unsigned long flags; enum aspeed_sgpio_reg reg; - bool is_input; int rc = 0; spin_lock_irqsave(&gpio->lock, flags); - is_input = gpio->dir_in[GPIO_BANK(offset)] & GPIO_BIT(offset); - reg = is_input ? reg_val : reg_rdata; + reg = aspeed_sgpio_is_input(offset) ? reg_val : reg_rdata; rc = !!(ioread32(bank_reg(gpio, bank, reg)) & GPIO_BIT(offset)); spin_unlock_irqrestore(&gpio->lock, flags); @@ -143,22 +191,31 @@ static int aspeed_sgpio_get(struct gpio_chip *gc, unsigned int offset) return rc; } -static void sgpio_set_value(struct gpio_chip *gc, unsigned int offset, int val) +static int sgpio_set_value(struct gpio_chip *gc, unsigned int offset, int val) { struct aspeed_sgpio *gpio = gpiochip_get_data(gc); const struct aspeed_sgpio_bank *bank = to_bank(offset); - void __iomem *addr; + void __iomem *addr_r, *addr_w; u32 reg = 0; - addr = bank_reg(gpio, bank, reg_val); - reg = ioread32(addr); + if (aspeed_sgpio_is_input(offset)) + return -EINVAL; + + /* Since this is an output, read the cached value from rdata, then + * update val. */ + addr_r = bank_reg(gpio, bank, reg_rdata); + addr_w = bank_reg(gpio, bank, reg_val); + + reg = ioread32(addr_r); if (val) reg |= GPIO_BIT(offset); else reg &= ~GPIO_BIT(offset); - iowrite32(reg, addr); + iowrite32(reg, addr_w); + + return 0; } static void aspeed_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val) @@ -175,43 +232,28 @@ static void aspeed_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val) static int aspeed_sgpio_dir_in(struct gpio_chip *gc, unsigned int offset) { - struct aspeed_sgpio *gpio = gpiochip_get_data(gc); - unsigned long flags; - - spin_lock_irqsave(&gpio->lock, flags); - gpio->dir_in[GPIO_BANK(offset)] |= GPIO_BIT(offset); - spin_unlock_irqrestore(&gpio->lock, flags); - - return 0; + return aspeed_sgpio_is_input(offset) ? 0 : -EINVAL; } static int aspeed_sgpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val) { struct aspeed_sgpio *gpio = gpiochip_get_data(gc); unsigned long flags; + int rc; - spin_lock_irqsave(&gpio->lock, flags); - - gpio->dir_in[GPIO_BANK(offset)] &= ~GPIO_BIT(offset); - sgpio_set_value(gc, offset, val); + /* No special action is required for setting the direction; we'll + * error-out in sgpio_set_value if this isn't an output GPIO */ + spin_lock_irqsave(&gpio->lock, flags); + rc = sgpio_set_value(gc, offset, val); spin_unlock_irqrestore(&gpio->lock, flags); - return 0; + return rc; } static int aspeed_sgpio_get_direction(struct gpio_chip *gc, unsigned int offset) { - int dir_status; - struct aspeed_sgpio *gpio = gpiochip_get_data(gc); - unsigned long flags; - - spin_lock_irqsave(&gpio->lock, flags); - dir_status = gpio->dir_in[GPIO_BANK(offset)] & GPIO_BIT(offset); - spin_unlock_irqrestore(&gpio->lock, flags); - - return dir_status; - + return !!aspeed_sgpio_is_input(offset); } static void irqd_to_aspeed_sgpio_data(struct irq_data *d, @@ -402,6 +444,7 @@ static int aspeed_sgpio_setup_irqs(struct aspeed_sgpio *gpio, irq = &gpio->chip.irq; irq->chip = &aspeed_sgpio_irqchip; + irq->init_valid_mask = aspeed_sgpio_irq_init_valid_mask; irq->handler = handle_bad_irq; irq->default_type = IRQ_TYPE_NONE; irq->parent_handler = aspeed_sgpio_irq_handler; @@ -452,11 +495,12 @@ static int __init aspeed_sgpio_probe(struct platform_device *pdev) if (rc < 0) { dev_err(&pdev->dev, "Could not read ngpios property\n"); return -EINVAL; - } else if (nr_gpios > MAX_NR_SGPIO) { + } else if (nr_gpios > MAX_NR_HW_SGPIO) { dev_err(&pdev->dev, "Number of GPIOs exceeds the maximum of %d: %d\n", - MAX_NR_SGPIO, nr_gpios); + MAX_NR_HW_SGPIO, nr_gpios); return -EINVAL; } + gpio->n_sgpio = nr_gpios; rc = of_property_read_u32(pdev->dev.of_node, "bus-frequency", &sgpio_freq); if (rc < 0) { @@ -497,7 +541,8 @@ static int __init aspeed_sgpio_probe(struct platform_device *pdev) spin_lock_init(&gpio->lock); gpio->chip.parent = &pdev->dev; - gpio->chip.ngpio = nr_gpios; + gpio->chip.ngpio = MAX_NR_HW_SGPIO * 2; + gpio->chip.init_valid_mask = aspeed_sgpio_init_valid_mask; gpio->chip.direction_input = aspeed_sgpio_dir_in; gpio->chip.direction_output = aspeed_sgpio_dir_out; gpio->chip.get_direction = aspeed_sgpio_get_direction; @@ -509,9 +554,6 @@ static int __init aspeed_sgpio_probe(struct platform_device *pdev) gpio->chip.label = dev_name(&pdev->dev); gpio->chip.base = -1; - /* set all SGPIO pins as input (1). */ - memset(gpio->dir_in, 0xff, sizeof(gpio->dir_in)); - aspeed_sgpio_setup_irqs(gpio, pdev); rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio); |