--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton NPCM Serial GPIO Driver
+ *
+ * Copyright (C) 2021 Nuvoton Technologies
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/gpio/driver.h>
+#include <linux/hashtable.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/units.h>
+
+#define MAX_NR_HW_SGPIO 64
+
+#define NPCM_IOXCFG1 0x2A
+#define NPCM_IOXCFG1_SFT_CLK GENMASK(3, 0)
+#define NPCM_IOXCFG1_SCLK_POL BIT(4)
+#define NPCM_IOXCFG1_LDSH_POL BIT(5)
+
+#define NPCM_IOXCTS 0x28
+#define NPCM_IOXCTS_IOXIF_EN BIT(7)
+#define NPCM_IOXCTS_RD_MODE GENMASK(2, 1)
+#define NPCM_IOXCTS_RD_MODE_PERIODIC BIT(2)
+
+#define NPCM_IOXCFG2 0x2B
+#define NPCM_IOXCFG2_PORT GENMASK(3, 0)
+
+#define NPCM_IXOEVCFG_MASK GENMASK(1, 0)
+#define NPCM_IXOEVCFG_FALLING BIT(1)
+#define NPCM_IXOEVCFG_RISING BIT(0)
+#define NPCM_IXOEVCFG_BOTH (NPCM_IXOEVCFG_FALLING | NPCM_IXOEVCFG_RISING)
+
+#define NPCM_CLK_MHZ (8 * HZ_PER_MHZ)
+#define NPCM_750_OPT 6
+#define NPCM_845_OPT 5
+
+#define GPIO_BANK(x) ((x) / 8)
+#define GPIO_BIT(x) ((x) % 8)
+
+/*
+ * Select the frequency of shift clock.
+ * The shift clock is a division of the APB clock.
+ */
+struct npcm_clk_cfg {
+ unsigned int *sft_clk;
+ unsigned int *clk_sel;
+ unsigned int cfg_opt;
+};
+
+struct npcm_sgpio {
+ struct gpio_chip chip;
+ struct clk *pclk;
+ struct irq_chip intc;
+ raw_spinlock_t lock;
+
+ void __iomem *base;
+ int irq;
+ u8 nin_sgpio;
+ u8 nout_sgpio;
+ u8 in_port;
+ u8 out_port;
+ u8 int_type[MAX_NR_HW_SGPIO];
+};
+
+struct npcm_sgpio_bank {
+ u8 rdata_reg;
+ u8 wdata_reg;
+ u8 event_config;
+ u8 event_status;
+};
+
+enum npcm_sgpio_reg {
+ READ_DATA,
+ WRITE_DATA,
+ EVENT_CFG,
+ EVENT_STS,
+};
+
+static const struct npcm_sgpio_bank npcm_sgpio_banks[] = {
+ {
+ .wdata_reg = 0x00,
+ .rdata_reg = 0x08,
+ .event_config = 0x10,
+ .event_status = 0x20,
+ },
+ {
+ .wdata_reg = 0x01,
+ .rdata_reg = 0x09,
+ .event_config = 0x12,
+ .event_status = 0x21,
+ },
+ {
+ .wdata_reg = 0x02,
+ .rdata_reg = 0x0a,
+ .event_config = 0x14,
+ .event_status = 0x22,
+ },
+ {
+ .wdata_reg = 0x03,
+ .rdata_reg = 0x0b,
+ .event_config = 0x16,
+ .event_status = 0x23,
+ },
+ {
+ .wdata_reg = 0x04,
+ .rdata_reg = 0x0c,
+ .event_config = 0x18,
+ .event_status = 0x24,
+ },
+ {
+ .wdata_reg = 0x05,
+ .rdata_reg = 0x0d,
+ .event_config = 0x1a,
+ .event_status = 0x25,
+ },
+ {
+ .wdata_reg = 0x06,
+ .rdata_reg = 0x0e,
+ .event_config = 0x1c,
+ .event_status = 0x26,
+ },
+ {
+ .wdata_reg = 0x07,
+ .rdata_reg = 0x0f,
+ .event_config = 0x1e,
+ .event_status = 0x27,
+ },
+};
+
+static void __iomem *bank_reg(struct npcm_sgpio *gpio,
+ const struct npcm_sgpio_bank *bank,
+ const enum npcm_sgpio_reg reg)
+{
+ switch (reg) {
+ case READ_DATA:
+ return gpio->base + bank->rdata_reg;
+ case WRITE_DATA:
+ return gpio->base + bank->wdata_reg;
+ case EVENT_CFG:
+ return gpio->base + bank->event_config;
+ case EVENT_STS:
+ return gpio->base + bank->event_status;
+ default:
+ /* actually if code runs to here, it's an error case */
+ dev_WARN(gpio->chip.parent, "Getting here is an error condition");
+ return NULL;
+ }
+}
+
+static const struct npcm_sgpio_bank *offset_to_bank(unsigned int offset)
+{
+ unsigned int bank = GPIO_BANK(offset);
+
+ return &npcm_sgpio_banks[bank];
+}
+
+static void npcm_sgpio_irqd_to_data(struct irq_data *d,
+ struct npcm_sgpio **gpio,
+ const struct npcm_sgpio_bank **bank,
+ u8 *bit, unsigned int *offset)
+{
+ struct npcm_sgpio *internal;
+
+ *offset = irqd_to_hwirq(d);
+ internal = irq_data_get_irq_chip_data(d);
+
+ *gpio = internal;
+ *offset -= internal->nout_sgpio;
+ *bank = offset_to_bank(*offset);
+ *bit = GPIO_BIT(*offset);
+}
+
+static int npcm_sgpio_init_port(struct npcm_sgpio *gpio)
+{
+ u8 in_port, out_port, set_port, reg;
+
+ in_port = GPIO_BANK(gpio->nin_sgpio);
+ if (GPIO_BIT(gpio->nin_sgpio) > 0)
+ in_port += 1;
+
+ out_port = GPIO_BANK(gpio->nout_sgpio);
+ if (GPIO_BIT(gpio->nout_sgpio) > 0)
+ out_port += 1;
+
+ gpio->in_port = in_port;
+ gpio->out_port = out_port;
+ set_port = (out_port & NPCM_IOXCFG2_PORT) << 4 |
+ (in_port & NPCM_IOXCFG2_PORT);
+ iowrite8(set_port, gpio->base + NPCM_IOXCFG2);
+
+ reg = ioread8(gpio->base + NPCM_IOXCFG2);
+
+ return reg == set_port ? 0 : -EINVAL;
+
+}
+
+static int npcm_sgpio_dir_in(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ return offset < gpio->nout_sgpio ? -EINVAL : 0;
+
+}
+
+static int npcm_sgpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ gc->set(gc, offset, val);
+
+ return 0;
+}
+
+static int npcm_sgpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ if (offset < gpio->nout_sgpio)
+ return GPIO_LINE_DIRECTION_OUT;
+
+ return GPIO_LINE_DIRECTION_IN;
+}
+
+static void npcm_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ const struct npcm_sgpio_bank *bank = offset_to_bank(offset);
+ void __iomem *addr;
+ u8 reg = 0;
+
+ addr = bank_reg(gpio, bank, WRITE_DATA);
+ reg = ioread8(addr);
+
+ if (val)
+ reg |= BIT(GPIO_BIT(offset));
+ else
+ reg &= ~BIT(GPIO_BIT(offset));
+
+ iowrite8(reg, addr);
+}
+
+static int npcm_sgpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ const struct npcm_sgpio_bank *bank;
+ void __iomem *addr;
+ u8 reg;
+
+ if (offset < gpio->nout_sgpio) {
+ bank = offset_to_bank(offset);
+ addr = bank_reg(gpio, bank, WRITE_DATA);
+ } else {
+ offset -= gpio->nout_sgpio;
+ bank = offset_to_bank(offset);
+ addr = bank_reg(gpio, bank, READ_DATA);
+ }
+
+ reg = ioread8(addr);
+
+ return !!(reg & BIT(GPIO_BIT(offset)));
+}
+
+static void npcm_sgpio_setup_enable(struct npcm_sgpio *gpio, bool enable)
+{
+ u8 reg;
+
+ reg = ioread8(gpio->base + NPCM_IOXCTS);
+ reg = (reg & ~NPCM_IOXCTS_RD_MODE) | NPCM_IOXCTS_RD_MODE_PERIODIC;
+
+ if (enable)
+ reg |= NPCM_IOXCTS_IOXIF_EN;
+ else
+ reg &= ~NPCM_IOXCTS_IOXIF_EN;
+
+ iowrite8(reg, gpio->base + NPCM_IOXCTS);
+}
+
+static int npcm_sgpio_setup_clk(struct npcm_sgpio *gpio,
+ const struct npcm_clk_cfg *clk_cfg)
+{
+ unsigned long apb_freq;
+ u32 val;
+ u8 tmp;
+ int i;
+
+ apb_freq = clk_get_rate(gpio->pclk);
+ tmp = ioread8(gpio->base + NPCM_IOXCFG1) & ~NPCM_IOXCFG1_SFT_CLK;
+
+ for (i = clk_cfg->cfg_opt-1; i > 0; i--) {
+ val = apb_freq / clk_cfg->sft_clk[i];
+ if (NPCM_CLK_MHZ > val) {
+ iowrite8(clk_cfg->clk_sel[i] | tmp,
+ gpio->base + NPCM_IOXCFG1);
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static void npcm_sgpio_irq_init_valid_mask(struct gpio_chip *gc,
+ unsigned long *valid_mask,
+ unsigned int ngpios)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ /* input GPIOs in the high range */
+ bitmap_set(valid_mask, gpio->nout_sgpio, gpio->nin_sgpio);
+ bitmap_clear(valid_mask, 0, gpio->nout_sgpio);
+}
+
+static void npcm_sgpio_irq_set_mask(struct irq_data *d, bool set)
+{
+ const struct npcm_sgpio_bank *bank;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ unsigned int offset;
+ u16 reg, type;
+ u8 bit;
+
+ npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
+ addr = bank_reg(gpio, bank, EVENT_CFG);
+
+ reg = ioread16(addr);
+ if (set) {
+ reg &= ~(NPCM_IXOEVCFG_MASK << (bit * 2));
+ } else {
+ type = gpio->int_type[offset];
+ reg |= (type << (bit * 2));
+ }
+
+ raw_spin_lock_irqsave(&gpio->lock, flags);
+
+ npcm_sgpio_setup_enable(gpio, false);
+
+ iowrite16(reg, addr);
+
+ npcm_sgpio_setup_enable(gpio, true);
+
+ addr = bank_reg(gpio, bank, EVENT_STS);
+ reg = ioread8(addr);
+ reg |= BIT(bit);
+ iowrite8(reg, addr);
+
+ raw_spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void npcm_sgpio_irq_ack(struct irq_data *d)
+{
+ const struct npcm_sgpio_bank *bank;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *status_addr;
+ unsigned int offset;
+ u8 bit;
+
+ npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
+ status_addr = bank_reg(gpio, bank, EVENT_STS);
+ raw_spin_lock_irqsave(&gpio->lock, flags);
+ iowrite8(BIT(bit), status_addr);
+ raw_spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void npcm_sgpio_irq_mask(struct irq_data *d)
+{
+ npcm_sgpio_irq_set_mask(d, true);
+}
+
+static void npcm_sgpio_irq_unmask(struct irq_data *d)
+{
+ npcm_sgpio_irq_set_mask(d, false);
+}
+
+static int npcm_sgpio_set_type(struct irq_data *d, unsigned int type)
+{
+ const struct npcm_sgpio_bank *bank;
+ irq_flow_handler_t handler;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ unsigned int offset;
+ u16 reg, val;
+ u8 bit;
+
+ npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_BOTH:
+ val = NPCM_IXOEVCFG_BOTH;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ case IRQ_TYPE_LEVEL_HIGH:
+ val = NPCM_IXOEVCFG_RISING;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ case IRQ_TYPE_LEVEL_LOW:
+ val = NPCM_IXOEVCFG_FALLING;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ handler = handle_level_irq;
+ else
+ handler = handle_edge_irq;
+
+ gpio->int_type[offset] = val;
+
+ raw_spin_lock_irqsave(&gpio->lock, flags);
+ npcm_sgpio_setup_enable(gpio, false);
+ addr = bank_reg(gpio, bank, EVENT_CFG);
+ reg = ioread16(addr);
+
+ reg |= (val << (bit * 2));
+
+ iowrite16(reg, addr);
+ npcm_sgpio_setup_enable(gpio, true);
+ raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+ irq_set_handler_locked(d, handler);
+
+ return 0;
+}
+
+static void npcm_sgpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct irq_chip *ic = irq_desc_get_chip(desc);
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ unsigned int i, j, girq;
+ unsigned long reg;
+
+ chained_irq_enter(ic, desc);
+
+ for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
+ const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
+
+ reg = ioread8(bank_reg(gpio, bank, EVENT_STS));
+ for_each_set_bit(j, ®, 8) {
+ girq = irq_find_mapping(gc->irq.domain,
+ i * 8 + gpio->nout_sgpio + j);
+ generic_handle_domain_irq(gc->irq.domain, girq);
+ }
+ }
+
+ chained_irq_exit(ic, desc);
+}
+
+static const struct irq_chip sgpio_irq_chip = {
+ .name = "sgpio-irq",
+ .irq_ack = npcm_sgpio_irq_ack,
+ .irq_mask = npcm_sgpio_irq_mask,
+ .irq_unmask = npcm_sgpio_irq_unmask,
+ .irq_set_type = npcm_sgpio_set_type,
+ .flags = IRQCHIP_IMMUTABLE | IRQCHIP_MASK_ON_SUSPEND,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int npcm_sgpio_setup_irqs(struct npcm_sgpio *gpio,
+ struct platform_device *pdev)
+{
+ int rc, i;
+ struct gpio_irq_chip *irq;
+
+ rc = platform_get_irq(pdev, 0);
+ if (rc < 0)
+ return rc;
+
+ gpio->irq = rc;
+
+ npcm_sgpio_setup_enable(gpio, false);
+
+ /* Disable IRQ and clear Interrupt status registers for all SGPIO Pins. */
+ for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
+ const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
+
+ iowrite16(0, bank_reg(gpio, bank, EVENT_CFG));
+ iowrite8(0xff, bank_reg(gpio, bank, EVENT_STS));
+ }
+
+ irq = &gpio->chip.irq;
+ gpio_irq_chip_set_chip(irq, &sgpio_irq_chip);
+ irq->init_valid_mask = npcm_sgpio_irq_init_valid_mask;
+ irq->handler = handle_bad_irq;
+ irq->default_type = IRQ_TYPE_NONE;
+ irq->parent_handler = npcm_sgpio_irq_handler;
+ irq->parent_handler_data = gpio;
+ irq->parents = &gpio->irq;
+ irq->num_parents = 1;
+
+ return 0;
+}
+
+static int npcm_sgpio_probe(struct platform_device *pdev)
+{
+ struct npcm_sgpio *gpio;
+ const struct npcm_clk_cfg *clk_cfg;
+ int rc;
+ u32 nin_gpios, nout_gpios;
+
+ gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ gpio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(gpio->base))
+ return PTR_ERR(gpio->base);
+
+ clk_cfg = device_get_match_data(&pdev->dev);
+ if (!clk_cfg)
+ return -EINVAL;
+
+ rc = device_property_read_u32(&pdev->dev, "nuvoton,input-ngpios",
+ &nin_gpios);
+ if (rc < 0)
+ return dev_err_probe(&pdev->dev, rc, "Could not read ngpios property\n");
+
+ rc = device_property_read_u32(&pdev->dev, "nuvoton,output-ngpios",
+ &nout_gpios);
+ if (rc < 0)
+ return dev_err_probe(&pdev->dev, rc, "Could not read ngpios property\n");
+
+ gpio->nin_sgpio = nin_gpios;
+ gpio->nout_sgpio = nout_gpios;
+ if (gpio->nin_sgpio > MAX_NR_HW_SGPIO ||
+ gpio->nout_sgpio > MAX_NR_HW_SGPIO)
+ return dev_err_probe(&pdev->dev, -EINVAL, "Number of GPIOs exceeds the maximum of %d: input: %d output: %d\n", MAX_NR_HW_SGPIO, nin_gpios, nout_gpios);
+
+ gpio->pclk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(gpio->pclk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(gpio->pclk), "Could not get pclk\n");
+
+ rc = npcm_sgpio_setup_clk(gpio, clk_cfg);
+ if (rc < 0)
+ return dev_err_probe(&pdev->dev, rc, "Failed to setup clock\n");
+
+ raw_spin_lock_init(&gpio->lock);
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.ngpio = gpio->nin_sgpio + gpio->nout_sgpio;
+ gpio->chip.direction_input = npcm_sgpio_dir_in;
+ gpio->chip.direction_output = npcm_sgpio_dir_out;
+ gpio->chip.get_direction = npcm_sgpio_get_direction;
+ gpio->chip.get = npcm_sgpio_get;
+ gpio->chip.set = npcm_sgpio_set;
+ gpio->chip.label = dev_name(&pdev->dev);
+ gpio->chip.base = -1;
+
+ rc = npcm_sgpio_init_port(gpio);
+ if (rc < 0)
+ return rc;
+
+ rc = npcm_sgpio_setup_irqs(gpio, pdev);
+ if (rc < 0)
+ return rc;
+
+ rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+ if (rc)
+ return dev_err_probe(&pdev->dev, rc, "GPIO registering failed\n");
+
+ npcm_sgpio_setup_enable(gpio, true);
+
+ return 0;
+}
+
+static unsigned int npcm750_SFT_CLK[NPCM_750_OPT] = {
+ 1024, 32, 8, 4, 3, 2,
+};
+
+static unsigned int npcm750_CLK_SEL[NPCM_750_OPT] = {
+ 0x00, 0x05, 0x07, 0x0C, 0x0D, 0x0E,
+};
+
+static unsigned int npcm845_SFT_CLK[NPCM_845_OPT] = {
+ 1024, 32, 16, 8, 4,
+};
+
+static unsigned int npcm845_CLK_SEL[NPCM_845_OPT] = {
+ 0x00, 0x05, 0x06, 0x07, 0x0C,
+};
+
+static struct npcm_clk_cfg npcm750_sgpio_pdata = {
+ .sft_clk = npcm750_SFT_CLK,
+ .clk_sel = npcm750_CLK_SEL,
+ .cfg_opt = NPCM_750_OPT,
+};
+
+static const struct npcm_clk_cfg npcm845_sgpio_pdata = {
+ .sft_clk = npcm845_SFT_CLK,
+ .clk_sel = npcm845_CLK_SEL,
+ .cfg_opt = NPCM_845_OPT,
+};
+
+static const struct of_device_id npcm_sgpio_of_table[] = {
+ { .compatible = "nuvoton,npcm750-sgpio", .data = &npcm750_sgpio_pdata, },
+ { .compatible = "nuvoton,npcm845-sgpio", .data = &npcm845_sgpio_pdata, },
+ {}
+};
+MODULE_DEVICE_TABLE(of, npcm_sgpio_of_table);
+
+static struct platform_driver npcm_sgpio_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = npcm_sgpio_of_table,
+ },
+ .probe = npcm_sgpio_probe,
+};
+module_platform_driver(npcm_sgpio_driver);
+
+MODULE_AUTHOR("Jim Liu <jjliu0@nuvoton.com>");
+MODULE_AUTHOR("Joseph Liu <kwliu@nuvoton.com>");
+MODULE_DESCRIPTION("Nuvoton NPCM Serial GPIO Driver");
+MODULE_LICENSE("GPL v2");
projects / users / hch / xfs.git / commitdiff