summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-104-dio-48e.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--drivers/gpio/gpio-104-dio-48e.c370
1 files changed, 370 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-104-dio-48e.c b/drivers/gpio/gpio-104-dio-48e.c
new file mode 100644
index 000000000..7b8829c8e
--- /dev/null
+++ b/drivers/gpio/gpio-104-dio-48e.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GPIO driver for the ACCES 104-DIO-48E series
+ * Copyright (C) 2016 William Breathitt Gray
+ *
+ * This driver supports the following ACCES devices: 104-DIO-48E and
+ * 104-DIO-24E.
+ */
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/irqdesc.h>
+#include <linux/isa.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include "gpio-i8255.h"
+
+MODULE_IMPORT_NS(I8255);
+
+#define DIO48E_EXTENT 16
+#define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
+
+static unsigned int base[MAX_NUM_DIO48E];
+static unsigned int num_dio48e;
+module_param_hw_array(base, uint, ioport, &num_dio48e, 0);
+MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses");
+
+static unsigned int irq[MAX_NUM_DIO48E];
+static unsigned int num_irq;
+module_param_hw_array(irq, uint, irq, &num_irq, 0);
+MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");
+
+#define DIO48E_NUM_PPI 2
+
+/**
+ * struct dio48e_reg - device register structure
+ * @ppi: Programmable Peripheral Interface groups
+ * @enable_buffer: Enable/Disable Buffer groups
+ * @unused1: Unused
+ * @enable_interrupt: Write: Enable Interrupt
+ * Read: Disable Interrupt
+ * @unused2: Unused
+ * @enable_counter: Write: Enable Counter/Timer Addressing
+ * Read: Disable Counter/Timer Addressing
+ * @unused3: Unused
+ * @clear_interrupt: Clear Interrupt
+ */
+struct dio48e_reg {
+ struct i8255 ppi[DIO48E_NUM_PPI];
+ u8 enable_buffer[DIO48E_NUM_PPI];
+ u8 unused1;
+ u8 enable_interrupt;
+ u8 unused2;
+ u8 enable_counter;
+ u8 unused3;
+ u8 clear_interrupt;
+};
+
+/**
+ * struct dio48e_gpio - GPIO device private data structure
+ * @chip: instance of the gpio_chip
+ * @ppi_state: PPI device states
+ * @lock: synchronization lock to prevent I/O race conditions
+ * @reg: I/O address offset for the device registers
+ * @irq_mask: I/O bits affected by interrupts
+ */
+struct dio48e_gpio {
+ struct gpio_chip chip;
+ struct i8255_state ppi_state[DIO48E_NUM_PPI];
+ raw_spinlock_t lock;
+ struct dio48e_reg __iomem *reg;
+ unsigned char irq_mask;
+};
+
+static int dio48e_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ if (i8255_get_direction(dio48egpio->ppi_state, offset))
+ return GPIO_LINE_DIRECTION_IN;
+
+ return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int dio48e_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ i8255_direction_input(dio48egpio->reg->ppi, dio48egpio->ppi_state,
+ offset);
+
+ return 0;
+}
+
+static int dio48e_gpio_direction_output(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ i8255_direction_output(dio48egpio->reg->ppi, dio48egpio->ppi_state,
+ offset, value);
+
+ return 0;
+}
+
+static int dio48e_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ return i8255_get(dio48egpio->reg->ppi, offset);
+}
+
+static int dio48e_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ i8255_get_multiple(dio48egpio->reg->ppi, mask, bits, chip->ngpio);
+
+ return 0;
+}
+
+static void dio48e_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ i8255_set(dio48egpio->reg->ppi, dio48egpio->ppi_state, offset, value);
+}
+
+static void dio48e_gpio_set_multiple(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+
+ i8255_set_multiple(dio48egpio->reg->ppi, dio48egpio->ppi_state, mask,
+ bits, chip->ngpio);
+}
+
+static void dio48e_irq_ack(struct irq_data *data)
+{
+}
+
+static void dio48e_irq_mask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+ const unsigned long offset = irqd_to_hwirq(data);
+ unsigned long flags;
+
+ /* only bit 3 on each respective Port C supports interrupts */
+ if (offset != 19 && offset != 43)
+ return;
+
+ raw_spin_lock_irqsave(&dio48egpio->lock, flags);
+
+ if (offset == 19)
+ dio48egpio->irq_mask &= ~BIT(0);
+ else
+ dio48egpio->irq_mask &= ~BIT(1);
+ gpiochip_disable_irq(chip, offset);
+
+ if (!dio48egpio->irq_mask)
+ /* disable interrupts */
+ ioread8(&dio48egpio->reg->enable_interrupt);
+
+ raw_spin_unlock_irqrestore(&dio48egpio->lock, flags);
+}
+
+static void dio48e_irq_unmask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+ const unsigned long offset = irqd_to_hwirq(data);
+ unsigned long flags;
+
+ /* only bit 3 on each respective Port C supports interrupts */
+ if (offset != 19 && offset != 43)
+ return;
+
+ raw_spin_lock_irqsave(&dio48egpio->lock, flags);
+
+ if (!dio48egpio->irq_mask) {
+ /* enable interrupts */
+ iowrite8(0x00, &dio48egpio->reg->clear_interrupt);
+ iowrite8(0x00, &dio48egpio->reg->enable_interrupt);
+ }
+
+ gpiochip_enable_irq(chip, offset);
+ if (offset == 19)
+ dio48egpio->irq_mask |= BIT(0);
+ else
+ dio48egpio->irq_mask |= BIT(1);
+
+ raw_spin_unlock_irqrestore(&dio48egpio->lock, flags);
+}
+
+static int dio48e_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+ const unsigned long offset = irqd_to_hwirq(data);
+
+ /* only bit 3 on each respective Port C supports interrupts */
+ if (offset != 19 && offset != 43)
+ return -EINVAL;
+
+ if (flow_type != IRQ_TYPE_NONE && flow_type != IRQ_TYPE_EDGE_RISING)
+ return -EINVAL;
+
+ return 0;
+}
+
+static const struct irq_chip dio48e_irqchip = {
+ .name = "104-dio-48e",
+ .irq_ack = dio48e_irq_ack,
+ .irq_mask = dio48e_irq_mask,
+ .irq_unmask = dio48e_irq_unmask,
+ .irq_set_type = dio48e_irq_set_type,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static irqreturn_t dio48e_irq_handler(int irq, void *dev_id)
+{
+ struct dio48e_gpio *const dio48egpio = dev_id;
+ struct gpio_chip *const chip = &dio48egpio->chip;
+ const unsigned long irq_mask = dio48egpio->irq_mask;
+ unsigned long gpio;
+
+ for_each_set_bit(gpio, &irq_mask, 2)
+ generic_handle_domain_irq(chip->irq.domain,
+ 19 + gpio*24);
+
+ raw_spin_lock(&dio48egpio->lock);
+
+ iowrite8(0x00, &dio48egpio->reg->clear_interrupt);
+
+ raw_spin_unlock(&dio48egpio->lock);
+
+ return IRQ_HANDLED;
+}
+
+#define DIO48E_NGPIO 48
+static const char *dio48e_names[DIO48E_NGPIO] = {
+ "PPI Group 0 Port A 0", "PPI Group 0 Port A 1", "PPI Group 0 Port A 2",
+ "PPI Group 0 Port A 3", "PPI Group 0 Port A 4", "PPI Group 0 Port A 5",
+ "PPI Group 0 Port A 6", "PPI Group 0 Port A 7", "PPI Group 0 Port B 0",
+ "PPI Group 0 Port B 1", "PPI Group 0 Port B 2", "PPI Group 0 Port B 3",
+ "PPI Group 0 Port B 4", "PPI Group 0 Port B 5", "PPI Group 0 Port B 6",
+ "PPI Group 0 Port B 7", "PPI Group 0 Port C 0", "PPI Group 0 Port C 1",
+ "PPI Group 0 Port C 2", "PPI Group 0 Port C 3", "PPI Group 0 Port C 4",
+ "PPI Group 0 Port C 5", "PPI Group 0 Port C 6", "PPI Group 0 Port C 7",
+ "PPI Group 1 Port A 0", "PPI Group 1 Port A 1", "PPI Group 1 Port A 2",
+ "PPI Group 1 Port A 3", "PPI Group 1 Port A 4", "PPI Group 1 Port A 5",
+ "PPI Group 1 Port A 6", "PPI Group 1 Port A 7", "PPI Group 1 Port B 0",
+ "PPI Group 1 Port B 1", "PPI Group 1 Port B 2", "PPI Group 1 Port B 3",
+ "PPI Group 1 Port B 4", "PPI Group 1 Port B 5", "PPI Group 1 Port B 6",
+ "PPI Group 1 Port B 7", "PPI Group 1 Port C 0", "PPI Group 1 Port C 1",
+ "PPI Group 1 Port C 2", "PPI Group 1 Port C 3", "PPI Group 1 Port C 4",
+ "PPI Group 1 Port C 5", "PPI Group 1 Port C 6", "PPI Group 1 Port C 7"
+};
+
+static int dio48e_irq_init_hw(struct gpio_chip *gc)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(gc);
+
+ /* Disable IRQ by default */
+ ioread8(&dio48egpio->reg->enable_interrupt);
+
+ return 0;
+}
+
+static void dio48e_init_ppi(struct i8255 __iomem *const ppi,
+ struct i8255_state *const ppi_state)
+{
+ const unsigned long ngpio = 24;
+ const unsigned long mask = GENMASK(ngpio - 1, 0);
+ const unsigned long bits = 0;
+ unsigned long i;
+
+ /* Initialize all GPIO to output 0 */
+ for (i = 0; i < DIO48E_NUM_PPI; i++) {
+ i8255_mode0_output(&ppi[i]);
+ i8255_set_multiple(&ppi[i], &ppi_state[i], &mask, &bits, ngpio);
+ }
+}
+
+static int dio48e_probe(struct device *dev, unsigned int id)
+{
+ struct dio48e_gpio *dio48egpio;
+ const char *const name = dev_name(dev);
+ struct gpio_irq_chip *girq;
+ int err;
+
+ dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL);
+ if (!dio48egpio)
+ return -ENOMEM;
+
+ if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) {
+ dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
+ base[id], base[id] + DIO48E_EXTENT);
+ return -EBUSY;
+ }
+
+ dio48egpio->reg = devm_ioport_map(dev, base[id], DIO48E_EXTENT);
+ if (!dio48egpio->reg)
+ return -ENOMEM;
+
+ dio48egpio->chip.label = name;
+ dio48egpio->chip.parent = dev;
+ dio48egpio->chip.owner = THIS_MODULE;
+ dio48egpio->chip.base = -1;
+ dio48egpio->chip.ngpio = DIO48E_NGPIO;
+ dio48egpio->chip.names = dio48e_names;
+ dio48egpio->chip.get_direction = dio48e_gpio_get_direction;
+ dio48egpio->chip.direction_input = dio48e_gpio_direction_input;
+ dio48egpio->chip.direction_output = dio48e_gpio_direction_output;
+ dio48egpio->chip.get = dio48e_gpio_get;
+ dio48egpio->chip.get_multiple = dio48e_gpio_get_multiple;
+ dio48egpio->chip.set = dio48e_gpio_set;
+ dio48egpio->chip.set_multiple = dio48e_gpio_set_multiple;
+
+ girq = &dio48egpio->chip.irq;
+ gpio_irq_chip_set_chip(girq, &dio48e_irqchip);
+ /* This will let us handle the parent IRQ in the driver */
+ girq->parent_handler = NULL;
+ girq->num_parents = 0;
+ girq->parents = NULL;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_edge_irq;
+ girq->init_hw = dio48e_irq_init_hw;
+
+ raw_spin_lock_init(&dio48egpio->lock);
+
+ i8255_state_init(dio48egpio->ppi_state, DIO48E_NUM_PPI);
+ dio48e_init_ppi(dio48egpio->reg->ppi, dio48egpio->ppi_state);
+
+ err = devm_gpiochip_add_data(dev, &dio48egpio->chip, dio48egpio);
+ if (err) {
+ dev_err(dev, "GPIO registering failed (%d)\n", err);
+ return err;
+ }
+
+ err = devm_request_irq(dev, irq[id], dio48e_irq_handler, 0, name,
+ dio48egpio);
+ if (err) {
+ dev_err(dev, "IRQ handler registering failed (%d)\n", err);
+ return err;
+ }
+
+ return 0;
+}
+
+static struct isa_driver dio48e_driver = {
+ .probe = dio48e_probe,
+ .driver = {
+ .name = "104-dio-48e"
+ },
+};
+module_isa_driver_with_irq(dio48e_driver, num_dio48e, num_irq);
+
+MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
+MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
+MODULE_LICENSE("GPL v2");