summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-ws16c48.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/gpio/gpio-ws16c48.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpio/gpio-ws16c48.c')
-rw-r--r--drivers/gpio/gpio-ws16c48.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c
new file mode 100644
index 000000000..6289b0510
--- /dev/null
+++ b/drivers/gpio/gpio-ws16c48.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GPIO driver for the WinSystems WS16C48
+ * Copyright (C) 2016 William Breathitt Gray
+ */
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/regmap.h>
+#include <linux/irq.h>
+#include <linux/isa.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/spinlock.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+
+#define WS16C48_EXTENT 11
+#define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT)
+
+static unsigned int base[MAX_NUM_WS16C48];
+static unsigned int num_ws16c48;
+module_param_hw_array(base, uint, ioport, &num_ws16c48, 0);
+MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
+
+static unsigned int irq[MAX_NUM_WS16C48];
+static unsigned int num_irq;
+module_param_hw_array(irq, uint, irq, &num_irq, 0);
+MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");
+
+#define WS16C48_DAT_BASE 0x0
+#define WS16C48_PAGE_LOCK 0x7
+#define WS16C48_PAGE_BASE 0x8
+#define WS16C48_POL WS16C48_PAGE_BASE
+#define WS16C48_ENAB WS16C48_PAGE_BASE
+#define WS16C48_INT_ID WS16C48_PAGE_BASE
+
+#define PAGE_LOCK_PAGE_FIELD GENMASK(7, 6)
+#define POL_PAGE u8_encode_bits(1, PAGE_LOCK_PAGE_FIELD)
+#define ENAB_PAGE u8_encode_bits(2, PAGE_LOCK_PAGE_FIELD)
+#define INT_ID_PAGE u8_encode_bits(3, PAGE_LOCK_PAGE_FIELD)
+
+static const struct regmap_range ws16c48_wr_ranges[] = {
+ regmap_reg_range(0x0, 0x5), regmap_reg_range(0x7, 0xA),
+};
+static const struct regmap_range ws16c48_rd_ranges[] = {
+ regmap_reg_range(0x0, 0xA),
+};
+static const struct regmap_range ws16c48_volatile_ranges[] = {
+ regmap_reg_range(0x0, 0x6), regmap_reg_range(0x8, 0xA),
+};
+static const struct regmap_access_table ws16c48_wr_table = {
+ .yes_ranges = ws16c48_wr_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ws16c48_wr_ranges),
+};
+static const struct regmap_access_table ws16c48_rd_table = {
+ .yes_ranges = ws16c48_rd_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ws16c48_rd_ranges),
+};
+static const struct regmap_access_table ws16c48_volatile_table = {
+ .yes_ranges = ws16c48_volatile_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ws16c48_volatile_ranges),
+};
+static const struct regmap_config ws16c48_regmap_config = {
+ .reg_bits = 8,
+ .reg_stride = 1,
+ .val_bits = 8,
+ .io_port = true,
+ .wr_table = &ws16c48_wr_table,
+ .rd_table = &ws16c48_rd_table,
+ .volatile_table = &ws16c48_volatile_table,
+ .cache_type = REGCACHE_FLAT,
+ .use_raw_spinlock = true,
+};
+
+#define WS16C48_NGPIO_PER_REG 8
+#define WS16C48_REGMAP_IRQ(_id) \
+ [_id] = { \
+ .reg_offset = (_id) / WS16C48_NGPIO_PER_REG, \
+ .mask = BIT((_id) % WS16C48_NGPIO_PER_REG), \
+ .type = { \
+ .type_reg_offset = (_id) / WS16C48_NGPIO_PER_REG, \
+ .types_supported = IRQ_TYPE_EDGE_BOTH, \
+ }, \
+ }
+
+/* Only the first 24 lines (Port 0-2) support interrupts */
+#define WS16C48_NUM_IRQS 24
+static const struct regmap_irq ws16c48_regmap_irqs[WS16C48_NUM_IRQS] = {
+ WS16C48_REGMAP_IRQ(0), WS16C48_REGMAP_IRQ(1), WS16C48_REGMAP_IRQ(2), /* 0-2 */
+ WS16C48_REGMAP_IRQ(3), WS16C48_REGMAP_IRQ(4), WS16C48_REGMAP_IRQ(5), /* 3-5 */
+ WS16C48_REGMAP_IRQ(6), WS16C48_REGMAP_IRQ(7), WS16C48_REGMAP_IRQ(8), /* 6-8 */
+ WS16C48_REGMAP_IRQ(9), WS16C48_REGMAP_IRQ(10), WS16C48_REGMAP_IRQ(11), /* 9-11 */
+ WS16C48_REGMAP_IRQ(12), WS16C48_REGMAP_IRQ(13), WS16C48_REGMAP_IRQ(14), /* 12-14 */
+ WS16C48_REGMAP_IRQ(15), WS16C48_REGMAP_IRQ(16), WS16C48_REGMAP_IRQ(17), /* 15-17 */
+ WS16C48_REGMAP_IRQ(18), WS16C48_REGMAP_IRQ(19), WS16C48_REGMAP_IRQ(20), /* 18-20 */
+ WS16C48_REGMAP_IRQ(21), WS16C48_REGMAP_IRQ(22), WS16C48_REGMAP_IRQ(23), /* 21-23 */
+};
+
+/**
+ * struct ws16c48_gpio - GPIO device private data structure
+ * @map: regmap for the device
+ * @lock: synchronization lock to prevent I/O race conditions
+ * @irq_mask: I/O bits affected by interrupts
+ */
+struct ws16c48_gpio {
+ struct regmap *map;
+ raw_spinlock_t lock;
+ u8 irq_mask[WS16C48_NUM_IRQS / WS16C48_NGPIO_PER_REG];
+};
+
+static int ws16c48_handle_pre_irq(void *const irq_drv_data) __acquires(&ws16c48gpio->lock)
+{
+ struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
+
+ /* Lock to prevent Page/Lock register change while we handle IRQ */
+ raw_spin_lock(&ws16c48gpio->lock);
+
+ return 0;
+}
+
+static int ws16c48_handle_post_irq(void *const irq_drv_data) __releases(&ws16c48gpio->lock)
+{
+ struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
+
+ raw_spin_unlock(&ws16c48gpio->lock);
+
+ return 0;
+}
+
+static int ws16c48_handle_mask_sync(const int index, const unsigned int mask_buf_def,
+ const unsigned int mask_buf, void *const irq_drv_data)
+{
+ struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
+ unsigned long flags;
+ int ret = 0;
+
+ raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
+
+ /* exit early if no change since the last mask sync */
+ if (mask_buf == ws16c48gpio->irq_mask[index])
+ goto exit_unlock;
+ ws16c48gpio->irq_mask[index] = mask_buf;
+
+ ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, ENAB_PAGE);
+ if (ret)
+ goto exit_unlock;
+
+ /* Update ENAB register (inverted mask) */
+ ret = regmap_write(ws16c48gpio->map, WS16C48_ENAB + index, ~mask_buf);
+ if (ret)
+ goto exit_unlock;
+
+ ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
+ if (ret)
+ goto exit_unlock;
+
+exit_unlock:
+ raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
+
+ return ret;
+}
+
+static int ws16c48_set_type_config(unsigned int **const buf, const unsigned int type,
+ const struct regmap_irq *const irq_data, const int idx,
+ void *const irq_drv_data)
+{
+ struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
+ unsigned int polarity;
+ unsigned long flags;
+ int ret;
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ polarity = irq_data->mask;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ polarity = 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
+
+ ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, POL_PAGE);
+ if (ret)
+ goto exit_unlock;
+
+ /* Set interrupt polarity */
+ ret = regmap_update_bits(ws16c48gpio->map, WS16C48_POL + idx, irq_data->mask, polarity);
+ if (ret)
+ goto exit_unlock;
+
+ ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
+ if (ret)
+ goto exit_unlock;
+
+exit_unlock:
+ raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
+
+ return ret;
+}
+
+#define WS16C48_NGPIO 48
+static const char *ws16c48_names[WS16C48_NGPIO] = {
+ "Port 0 Bit 0", "Port 0 Bit 1", "Port 0 Bit 2", "Port 0 Bit 3",
+ "Port 0 Bit 4", "Port 0 Bit 5", "Port 0 Bit 6", "Port 0 Bit 7",
+ "Port 1 Bit 0", "Port 1 Bit 1", "Port 1 Bit 2", "Port 1 Bit 3",
+ "Port 1 Bit 4", "Port 1 Bit 5", "Port 1 Bit 6", "Port 1 Bit 7",
+ "Port 2 Bit 0", "Port 2 Bit 1", "Port 2 Bit 2", "Port 2 Bit 3",
+ "Port 2 Bit 4", "Port 2 Bit 5", "Port 2 Bit 6", "Port 2 Bit 7",
+ "Port 3 Bit 0", "Port 3 Bit 1", "Port 3 Bit 2", "Port 3 Bit 3",
+ "Port 3 Bit 4", "Port 3 Bit 5", "Port 3 Bit 6", "Port 3 Bit 7",
+ "Port 4 Bit 0", "Port 4 Bit 1", "Port 4 Bit 2", "Port 4 Bit 3",
+ "Port 4 Bit 4", "Port 4 Bit 5", "Port 4 Bit 6", "Port 4 Bit 7",
+ "Port 5 Bit 0", "Port 5 Bit 1", "Port 5 Bit 2", "Port 5 Bit 3",
+ "Port 5 Bit 4", "Port 5 Bit 5", "Port 5 Bit 6", "Port 5 Bit 7"
+};
+
+static int ws16c48_irq_init_hw(struct regmap *const map)
+{
+ int err;
+
+ err = regmap_write(map, WS16C48_PAGE_LOCK, ENAB_PAGE);
+ if (err)
+ return err;
+
+ /* Disable interrupts for all lines */
+ err = regmap_write(map, WS16C48_ENAB + 0, 0x00);
+ if (err)
+ return err;
+ err = regmap_write(map, WS16C48_ENAB + 1, 0x00);
+ if (err)
+ return err;
+ err = regmap_write(map, WS16C48_ENAB + 2, 0x00);
+ if (err)
+ return err;
+
+ return regmap_write(map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
+}
+
+static int ws16c48_probe(struct device *dev, unsigned int id)
+{
+ struct ws16c48_gpio *ws16c48gpio;
+ const char *const name = dev_name(dev);
+ int err;
+ struct gpio_regmap_config gpio_config = {};
+ void __iomem *regs;
+ struct regmap_irq_chip *chip;
+ struct regmap_irq_chip_data *chip_data;
+
+ ws16c48gpio = devm_kzalloc(dev, sizeof(*ws16c48gpio), GFP_KERNEL);
+ if (!ws16c48gpio)
+ return -ENOMEM;
+
+ if (!devm_request_region(dev, base[id], WS16C48_EXTENT, name)) {
+ dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
+ base[id], base[id] + WS16C48_EXTENT);
+ return -EBUSY;
+ }
+
+ regs = devm_ioport_map(dev, base[id], WS16C48_EXTENT);
+ if (!regs)
+ return -ENOMEM;
+
+ ws16c48gpio->map = devm_regmap_init_mmio(dev, regs, &ws16c48_regmap_config);
+ if (IS_ERR(ws16c48gpio->map))
+ return dev_err_probe(dev, PTR_ERR(ws16c48gpio->map),
+ "Unable to initialize register map\n");
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->name = name;
+ chip->status_base = WS16C48_INT_ID;
+ chip->mask_base = WS16C48_ENAB;
+ chip->ack_base = WS16C48_INT_ID;
+ chip->num_regs = 3;
+ chip->irqs = ws16c48_regmap_irqs;
+ chip->num_irqs = ARRAY_SIZE(ws16c48_regmap_irqs);
+ chip->handle_pre_irq = ws16c48_handle_pre_irq;
+ chip->handle_post_irq = ws16c48_handle_post_irq;
+ chip->handle_mask_sync = ws16c48_handle_mask_sync;
+ chip->set_type_config = ws16c48_set_type_config;
+ chip->irq_drv_data = ws16c48gpio;
+
+ raw_spin_lock_init(&ws16c48gpio->lock);
+
+ /* Initialize to prevent spurious interrupts before we're ready */
+ err = ws16c48_irq_init_hw(ws16c48gpio->map);
+ if (err)
+ return err;
+
+ err = devm_regmap_add_irq_chip(dev, ws16c48gpio->map, irq[id], 0, 0, chip, &chip_data);
+ if (err)
+ return dev_err_probe(dev, err, "IRQ registration failed\n");
+
+ gpio_config.parent = dev;
+ gpio_config.regmap = ws16c48gpio->map;
+ gpio_config.ngpio = WS16C48_NGPIO;
+ gpio_config.names = ws16c48_names;
+ gpio_config.reg_dat_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
+ gpio_config.reg_set_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
+ /* Setting a GPIO to 0 allows it to be used as an input */
+ gpio_config.reg_dir_out_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
+ gpio_config.ngpio_per_reg = WS16C48_NGPIO_PER_REG;
+ gpio_config.irq_domain = regmap_irq_get_domain(chip_data);
+
+ return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config));
+}
+
+static struct isa_driver ws16c48_driver = {
+ .probe = ws16c48_probe,
+ .driver = {
+ .name = "ws16c48"
+ },
+};
+
+module_isa_driver_with_irq(ws16c48_driver, num_ws16c48, num_irq);
+
+MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
+MODULE_DESCRIPTION("WinSystems WS16C48 GPIO driver");
+MODULE_LICENSE("GPL v2");