From 2c05a0f29f41cbb1e31e94a53e7dacf0622706bb Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Wed, 20 Jul 2022 09:45:57 -0400 Subject: gpio: ws16c48: Implement and utilize register structures Reduce magic numbers and improve code readability by implementing and utilizing named register data structures. Reviewed-by: Linus Walleij Cc: Paul Demetrotion Signed-off-by: William Breathitt Gray Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpio-ws16c48.c | 120 +++++++++++++++++++++++++++++++------------- 1 file changed, 84 insertions(+), 36 deletions(-) (limited to 'drivers/gpio/gpio-ws16c48.c') diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c index 5078631d8014..b098f2dc196b 100644 --- a/drivers/gpio/gpio-ws16c48.c +++ b/drivers/gpio/gpio-ws16c48.c @@ -4,7 +4,6 @@ * Copyright (C) 2016 William Breathitt Gray */ #include -#include #include #include #include @@ -17,8 +16,9 @@ #include #include #include +#include -#define WS16C48_EXTENT 16 +#define WS16C48_EXTENT 10 #define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT) static unsigned int base[MAX_NUM_WS16C48]; @@ -30,6 +30,20 @@ static unsigned int irq[MAX_NUM_WS16C48]; module_param_hw_array(irq, uint, irq, NULL, 0); MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers"); +/** + * struct ws16c48_reg - device register structure + * @port: Port 0 through 5 I/O + * @int_pending: Interrupt Pending + * @page_lock: Register page (Bits 7-6) and I/O port lock (Bits 5-0) + * @pol_enab_int_id: Interrupt polarity, enable, and ID + */ +struct ws16c48_reg { + u8 port[6]; + u8 int_pending; + u8 page_lock; + u8 pol_enab_int_id[3]; +}; + /** * struct ws16c48_gpio - GPIO device private data structure * @chip: instance of the gpio_chip @@ -38,7 +52,7 @@ MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers"); * @lock: synchronization lock to prevent I/O race conditions * @irq_mask: I/O bits affected by interrupts * @flow_mask: IRQ flow type mask for the respective I/O bits - * @base: base port address of the GPIO device + * @reg: I/O address offset for the device registers */ struct ws16c48_gpio { struct gpio_chip chip; @@ -47,7 +61,7 @@ struct ws16c48_gpio { raw_spinlock_t lock; unsigned long irq_mask; unsigned long flow_mask; - void __iomem *base; + struct ws16c48_reg __iomem *reg; }; static int ws16c48_gpio_get_direction(struct gpio_chip *chip, unsigned offset) @@ -73,7 +87,7 @@ static int ws16c48_gpio_direction_input(struct gpio_chip *chip, unsigned offset) ws16c48gpio->io_state[port] |= mask; ws16c48gpio->out_state[port] &= ~mask; - iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->base + port); + iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->reg->port + port); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); @@ -95,7 +109,7 @@ static int ws16c48_gpio_direction_output(struct gpio_chip *chip, ws16c48gpio->out_state[port] |= mask; else ws16c48gpio->out_state[port] &= ~mask; - iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->base + port); + iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->reg->port + port); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); @@ -118,7 +132,7 @@ static int ws16c48_gpio_get(struct gpio_chip *chip, unsigned offset) return -EINVAL; } - port_state = ioread8(ws16c48gpio->base + port); + port_state = ioread8(ws16c48gpio->reg->port + port); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); @@ -131,14 +145,16 @@ static int ws16c48_gpio_get_multiple(struct gpio_chip *chip, struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip); unsigned long offset; unsigned long gpio_mask; - void __iomem *port_addr; + size_t index; + u8 __iomem *port_addr; unsigned long port_state; /* clear bits array to a clean slate */ bitmap_zero(bits, chip->ngpio); for_each_set_clump8(offset, gpio_mask, mask, chip->ngpio) { - port_addr = ws16c48gpio->base + offset / 8; + index = offset / 8; + port_addr = ws16c48gpio->reg->port + index; port_state = ioread8(port_addr) & gpio_mask; bitmap_set_value8(bits, port_state, offset); @@ -166,7 +182,7 @@ static void ws16c48_gpio_set(struct gpio_chip *chip, unsigned offset, int value) ws16c48gpio->out_state[port] |= mask; else ws16c48gpio->out_state[port] &= ~mask; - iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->base + port); + iowrite8(ws16c48gpio->out_state[port], ws16c48gpio->reg->port + port); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); } @@ -178,13 +194,13 @@ static void ws16c48_gpio_set_multiple(struct gpio_chip *chip, unsigned long offset; unsigned long gpio_mask; size_t index; - void __iomem *port_addr; + u8 __iomem *port_addr; unsigned long bitmask; unsigned long flags; for_each_set_clump8(offset, gpio_mask, mask, chip->ngpio) { index = offset / 8; - port_addr = ws16c48gpio->base + index; + port_addr = ws16c48gpio->reg->port + index; /* mask out GPIO configured for input */ gpio_mask &= ~ws16c48gpio->io_state[index]; @@ -219,10 +235,15 @@ static void ws16c48_irq_ack(struct irq_data *data) port_state = ws16c48gpio->irq_mask >> (8*port); - iowrite8(0x80, ws16c48gpio->base + 7); - iowrite8(port_state & ~mask, ws16c48gpio->base + 8 + port); - iowrite8(port_state | mask, ws16c48gpio->base + 8 + port); - iowrite8(0xC0, ws16c48gpio->base + 7); + /* Select Register Page 2; Unlock all I/O ports */ + iowrite8(0x80, &ws16c48gpio->reg->page_lock); + + /* Clear pending interrupt */ + iowrite8(port_state & ~mask, ws16c48gpio->reg->pol_enab_int_id + port); + iowrite8(port_state | mask, ws16c48gpio->reg->pol_enab_int_id + port); + + /* Select Register Page 3; Unlock all I/O ports */ + iowrite8(0xC0, &ws16c48gpio->reg->page_lock); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); } @@ -235,6 +256,7 @@ static void ws16c48_irq_mask(struct irq_data *data) const unsigned long mask = BIT(offset); const unsigned port = offset / 8; unsigned long flags; + unsigned long port_state; /* only the first 3 ports support interrupts */ if (port > 2) @@ -243,10 +265,16 @@ static void ws16c48_irq_mask(struct irq_data *data) raw_spin_lock_irqsave(&ws16c48gpio->lock, flags); ws16c48gpio->irq_mask &= ~mask; + port_state = ws16c48gpio->irq_mask >> (8 * port); + + /* Select Register Page 2; Unlock all I/O ports */ + iowrite8(0x80, &ws16c48gpio->reg->page_lock); - iowrite8(0x80, ws16c48gpio->base + 7); - iowrite8(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port); - iowrite8(0xC0, ws16c48gpio->base + 7); + /* Disable interrupt */ + iowrite8(port_state, ws16c48gpio->reg->pol_enab_int_id + port); + + /* Select Register Page 3; Unlock all I/O ports */ + iowrite8(0xC0, &ws16c48gpio->reg->page_lock); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); } @@ -259,6 +287,7 @@ static void ws16c48_irq_unmask(struct irq_data *data) const unsigned long mask = BIT(offset); const unsigned port = offset / 8; unsigned long flags; + unsigned long port_state; /* only the first 3 ports support interrupts */ if (port > 2) @@ -267,10 +296,16 @@ static void ws16c48_irq_unmask(struct irq_data *data) raw_spin_lock_irqsave(&ws16c48gpio->lock, flags); ws16c48gpio->irq_mask |= mask; + port_state = ws16c48gpio->irq_mask >> (8 * port); + + /* Select Register Page 2; Unlock all I/O ports */ + iowrite8(0x80, &ws16c48gpio->reg->page_lock); - iowrite8(0x80, ws16c48gpio->base + 7); - iowrite8(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port); - iowrite8(0xC0, ws16c48gpio->base + 7); + /* Enable interrupt */ + iowrite8(port_state, ws16c48gpio->reg->pol_enab_int_id + port); + + /* Select Register Page 3; Unlock all I/O ports */ + iowrite8(0xC0, &ws16c48gpio->reg->page_lock); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); } @@ -283,6 +318,7 @@ static int ws16c48_irq_set_type(struct irq_data *data, unsigned flow_type) const unsigned long mask = BIT(offset); const unsigned port = offset / 8; unsigned long flags; + unsigned long port_state; /* only the first 3 ports support interrupts */ if (port > 2) @@ -304,9 +340,16 @@ static int ws16c48_irq_set_type(struct irq_data *data, unsigned flow_type) return -EINVAL; } - iowrite8(0x40, ws16c48gpio->base + 7); - iowrite8(ws16c48gpio->flow_mask >> (8*port), ws16c48gpio->base + 8 + port); - iowrite8(0xC0, ws16c48gpio->base + 7); + port_state = ws16c48gpio->flow_mask >> (8 * port); + + /* Select Register Page 1; Unlock all I/O ports */ + iowrite8(0x40, &ws16c48gpio->reg->page_lock); + + /* Set interrupt polarity */ + iowrite8(port_state, ws16c48gpio->reg->pol_enab_int_id + port); + + /* Select Register Page 3; Unlock all I/O ports */ + iowrite8(0xC0, &ws16c48gpio->reg->page_lock); raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags); @@ -325,25 +368,26 @@ static irqreturn_t ws16c48_irq_handler(int irq, void *dev_id) { struct ws16c48_gpio *const ws16c48gpio = dev_id; struct gpio_chip *const chip = &ws16c48gpio->chip; + struct ws16c48_reg __iomem *const reg = ws16c48gpio->reg; unsigned long int_pending; unsigned long port; unsigned long int_id; unsigned long gpio; - int_pending = ioread8(ws16c48gpio->base + 6) & 0x7; + int_pending = ioread8(®->int_pending) & 0x7; if (!int_pending) return IRQ_NONE; /* loop until all pending interrupts are handled */ do { for_each_set_bit(port, &int_pending, 3) { - int_id = ioread8(ws16c48gpio->base + 8 + port); + int_id = ioread8(reg->pol_enab_int_id + port); for_each_set_bit(gpio, &int_id, 8) generic_handle_domain_irq(chip->irq.domain, gpio + 8*port); } - int_pending = ioread8(ws16c48gpio->base + 6) & 0x7; + int_pending = ioread8(®->int_pending) & 0x7; } while (int_pending); return IRQ_HANDLED; @@ -369,12 +413,16 @@ static int ws16c48_irq_init_hw(struct gpio_chip *gc) { struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(gc); - /* Disable IRQ by default */ - iowrite8(0x80, ws16c48gpio->base + 7); - iowrite8(0, ws16c48gpio->base + 8); - iowrite8(0, ws16c48gpio->base + 9); - iowrite8(0, ws16c48gpio->base + 10); - iowrite8(0xC0, ws16c48gpio->base + 7); + /* Select Register Page 2; Unlock all I/O ports */ + iowrite8(0x80, &ws16c48gpio->reg->page_lock); + + /* Disable interrupts for all lines */ + iowrite8(0, &ws16c48gpio->reg->pol_enab_int_id[0]); + iowrite8(0, &ws16c48gpio->reg->pol_enab_int_id[1]); + iowrite8(0, &ws16c48gpio->reg->pol_enab_int_id[2]); + + /* Select Register Page 3; Unlock all I/O ports */ + iowrite8(0xC0, &ws16c48gpio->reg->page_lock); return 0; } @@ -396,8 +444,8 @@ static int ws16c48_probe(struct device *dev, unsigned int id) return -EBUSY; } - ws16c48gpio->base = devm_ioport_map(dev, base[id], WS16C48_EXTENT); - if (!ws16c48gpio->base) + ws16c48gpio->reg = devm_ioport_map(dev, base[id], WS16C48_EXTENT); + if (!ws16c48gpio->reg) return -ENOMEM; ws16c48gpio->chip.label = name; -- cgit v1.2.3