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authorLinus Torvalds <torvalds@linux-foundation.org>2019-12-01 17:56:50 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-01 17:56:50 -0800
commit99a0d9f5e87352c4bd8d01bc9b39f7091c12e4d4 (patch)
treedb8608677da8ec882f495bfb3885727f2a5b5d40 /drivers/gpio/gpio-aspeed-sgpio.c
parent37323918cac24c89facdc009b0566b25cce94ea5 (diff)
parent41c4616bb81ff9b2efd981453f2c5d8f57d0c0b8 (diff)
Merge tag 'gpio-v5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for the v5.5 kernel cycle Core changes: - Expose pull up/down flags for the GPIO character device to userspace. After clear input from the RaspberryPi and Beagle communities, it has been established that prototyping, industrial automation and make communities strongly need this feature, and as we want people to use the character device, we have implemented the simple pull up/down interface for GPIO lines. This means we can specify that a (chip-specific) pull up/down resistor can be enabled, but does not offer fine-grained control such as cases where the resistance of the same pull resistor can be controlled (yet). - Introduce devm_fwnode_gpiod_get_index() and start to phase out the old symbol devm_fwnode_get_index_gpiod_from_child(). - A bit of documentation clean-up work. - Introduce a define for GPIO line directions and deploy it in all GPIO drivers in the drivers/gpio directory. - Add a special callback to populate pin ranges when cooperating with the pin control subsystem and registering ranges as part of adding a gpiolib driver and a gpio_irq_chip driver at the same time. This is also deployed in the Intel Merrifield driver. New drivers: - RDA Micro GPIO controller. - XGS-iproc GPIO driver. Driver improvements: - Wake event and debounce support on the Tegra 186 driver. - Finalize the Aspeed SGPIO driver. - MPC8xxx uses a normal IRQ handler rather than a chained handler" * tag 'gpio-v5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (64 commits) gpio: Add TODO item for regmap helper Documentation: gpio: driver.rst: Fix warnings gpio: of: Fix bogus reference to gpiod_get_count() gpiolib: Grammar s/manager/managed/ gpio: lynxpoint: Setup correct IRQ handlers MAINTAINERS: Replace my email by one @kernel.org gpiolib: acpi: Make acpi_gpiochip_alloc_event always return AE_OK gpio/mpc8xxx: fix qoriq GPIO reading gpio: mpc8xxx: Don't overwrite default irq_set_type callback gpiolib: acpi: Print pin number on acpi_gpiochip_alloc_event errors gpiolib: fix coding style in gpiod_hog() drm/bridge: ti-tfp410: switch to using fwnode_gpiod_get_index() gpio: merrifield: Pass irqchip when adding gpiochip gpio: merrifield: Add GPIO <-> pin mapping ranges via callback gpiolib: Introduce ->add_pin_ranges() callback gpio: mmio: remove untrue leftover comment gpio: em: Use platform_get_irq() to obtain interrupts gpio: tegra186: Add debounce support gpio: tegra186: Program interrupt route mapping gpio: tegra186: Derive register offsets from bank/port ...
Diffstat (limited to 'drivers/gpio/gpio-aspeed-sgpio.c')
-rw-r--r--drivers/gpio/gpio-aspeed-sgpio.c533
1 files changed, 533 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-aspeed-sgpio.c b/drivers/gpio/gpio-aspeed-sgpio.c
new file mode 100644
index 000000000000..7e99860ca447
--- /dev/null
+++ b/drivers/gpio/gpio-aspeed-sgpio.c
@@ -0,0 +1,533 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2019 American Megatrends International LLC.
+ *
+ * Author: Karthikeyan Mani <karthikeyanm@amiindia.co.in>
+ */
+
+#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/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#define MAX_NR_SGPIO 80
+
+#define ASPEED_SGPIO_CTRL 0x54
+
+#define ASPEED_SGPIO_PINS_MASK GENMASK(9, 6)
+#define ASPEED_SGPIO_CLK_DIV_MASK GENMASK(31, 16)
+#define ASPEED_SGPIO_ENABLE BIT(0)
+
+struct aspeed_sgpio {
+ struct gpio_chip chip;
+ struct clk *pclk;
+ spinlock_t lock;
+ void __iomem *base;
+ uint32_t dir_in[3];
+ int irq;
+};
+
+struct aspeed_sgpio_bank {
+ uint16_t val_regs;
+ uint16_t rdata_reg;
+ uint16_t irq_regs;
+ const char names[4][3];
+};
+
+/*
+ * Note: The "value" register returns the input value when the GPIO is
+ * configured as an input.
+ *
+ * The "rdata" register returns the output value when the GPIO is
+ * configured as an output.
+ */
+static const struct aspeed_sgpio_bank aspeed_sgpio_banks[] = {
+ {
+ .val_regs = 0x0000,
+ .rdata_reg = 0x0070,
+ .irq_regs = 0x0004,
+ .names = { "A", "B", "C", "D" },
+ },
+ {
+ .val_regs = 0x001C,
+ .rdata_reg = 0x0074,
+ .irq_regs = 0x0020,
+ .names = { "E", "F", "G", "H" },
+ },
+ {
+ .val_regs = 0x0038,
+ .rdata_reg = 0x0078,
+ .irq_regs = 0x003C,
+ .names = { "I", "J" },
+ },
+};
+
+enum aspeed_sgpio_reg {
+ reg_val,
+ reg_rdata,
+ reg_irq_enable,
+ reg_irq_type0,
+ reg_irq_type1,
+ reg_irq_type2,
+ reg_irq_status,
+};
+
+#define GPIO_VAL_VALUE 0x00
+#define GPIO_IRQ_ENABLE 0x00
+#define GPIO_IRQ_TYPE0 0x04
+#define GPIO_IRQ_TYPE1 0x08
+#define GPIO_IRQ_TYPE2 0x0C
+#define GPIO_IRQ_STATUS 0x10
+
+static void __iomem *bank_reg(struct aspeed_sgpio *gpio,
+ const struct aspeed_sgpio_bank *bank,
+ const enum aspeed_sgpio_reg reg)
+{
+ switch (reg) {
+ case reg_val:
+ return gpio->base + bank->val_regs + GPIO_VAL_VALUE;
+ case reg_rdata:
+ return gpio->base + bank->rdata_reg;
+ case reg_irq_enable:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_ENABLE;
+ case reg_irq_type0:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE0;
+ case reg_irq_type1:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE1;
+ case reg_irq_type2:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
+ case reg_irq_status:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
+ default:
+ /* acturally if code runs to here, it's an error case */
+ BUG_ON(1);
+ }
+}
+
+#define GPIO_BANK(x) ((x) >> 5)
+#define GPIO_OFFSET(x) ((x) & 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);
+
+ WARN_ON(bank >= ARRAY_SIZE(aspeed_sgpio_banks));
+ return &aspeed_sgpio_banks[bank];
+}
+
+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;
+ rc = !!(ioread32(bank_reg(gpio, bank, reg)) & GPIO_BIT(offset));
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return rc;
+}
+
+static void 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;
+ u32 reg = 0;
+
+ addr = bank_reg(gpio, bank, reg_val);
+ reg = ioread32(addr);
+
+ if (val)
+ reg |= GPIO_BIT(offset);
+ else
+ reg &= ~GPIO_BIT(offset);
+
+ iowrite32(reg, addr);
+}
+
+static void aspeed_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct aspeed_sgpio *gpio = gpiochip_get_data(gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ sgpio_set_value(gc, offset, val);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+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;
+}
+
+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;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ gpio->dir_in[GPIO_BANK(offset)] &= ~GPIO_BIT(offset);
+ sgpio_set_value(gc, offset, val);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
+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;
+
+}
+
+static void irqd_to_aspeed_sgpio_data(struct irq_data *d,
+ struct aspeed_sgpio **gpio,
+ const struct aspeed_sgpio_bank **bank,
+ u32 *bit, int *offset)
+{
+ struct aspeed_sgpio *internal;
+
+ *offset = irqd_to_hwirq(d);
+ internal = irq_data_get_irq_chip_data(d);
+ WARN_ON(!internal);
+
+ *gpio = internal;
+ *bank = to_bank(*offset);
+ *bit = GPIO_BIT(*offset);
+}
+
+static void aspeed_sgpio_irq_ack(struct irq_data *d)
+{
+ const struct aspeed_sgpio_bank *bank;
+ struct aspeed_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *status_addr;
+ int offset;
+ u32 bit;
+
+ irqd_to_aspeed_sgpio_data(d, &gpio, &bank, &bit, &offset);
+
+ status_addr = bank_reg(gpio, bank, reg_irq_status);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ iowrite32(bit, status_addr);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void aspeed_sgpio_irq_set_mask(struct irq_data *d, bool set)
+{
+ const struct aspeed_sgpio_bank *bank;
+ struct aspeed_sgpio *gpio;
+ unsigned long flags;
+ u32 reg, bit;
+ void __iomem *addr;
+ int offset;
+
+ irqd_to_aspeed_sgpio_data(d, &gpio, &bank, &bit, &offset);
+ addr = bank_reg(gpio, bank, reg_irq_enable);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ reg = ioread32(addr);
+ if (set)
+ reg |= bit;
+ else
+ reg &= ~bit;
+
+ iowrite32(reg, addr);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void aspeed_sgpio_irq_mask(struct irq_data *d)
+{
+ aspeed_sgpio_irq_set_mask(d, false);
+}
+
+static void aspeed_sgpio_irq_unmask(struct irq_data *d)
+{
+ aspeed_sgpio_irq_set_mask(d, true);
+}
+
+static int aspeed_sgpio_set_type(struct irq_data *d, unsigned int type)
+{
+ u32 type0 = 0;
+ u32 type1 = 0;
+ u32 type2 = 0;
+ u32 bit, reg;
+ const struct aspeed_sgpio_bank *bank;
+ irq_flow_handler_t handler;
+ struct aspeed_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ int offset;
+
+ irqd_to_aspeed_sgpio_data(d, &gpio, &bank, &bit, &offset);
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_BOTH:
+ type2 |= bit;
+ /* fall through */
+ case IRQ_TYPE_EDGE_RISING:
+ type0 |= bit;
+ /* fall through */
+ case IRQ_TYPE_EDGE_FALLING:
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ type0 |= bit;
+ /* fall through */
+ case IRQ_TYPE_LEVEL_LOW:
+ type1 |= bit;
+ handler = handle_level_irq;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ addr = bank_reg(gpio, bank, reg_irq_type0);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type0;
+ iowrite32(reg, addr);
+
+ addr = bank_reg(gpio, bank, reg_irq_type1);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type1;
+ iowrite32(reg, addr);
+
+ addr = bank_reg(gpio, bank, reg_irq_type2);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type2;
+ iowrite32(reg, addr);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ irq_set_handler_locked(d, handler);
+
+ return 0;
+}
+
+static void aspeed_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 aspeed_sgpio *data = gpiochip_get_data(gc);
+ unsigned int i, p, girq;
+ unsigned long reg;
+
+ chained_irq_enter(ic, desc);
+
+ for (i = 0; i < ARRAY_SIZE(aspeed_sgpio_banks); i++) {
+ const struct aspeed_sgpio_bank *bank = &aspeed_sgpio_banks[i];
+
+ reg = ioread32(bank_reg(data, bank, reg_irq_status));
+
+ for_each_set_bit(p, &reg, 32) {
+ girq = irq_find_mapping(gc->irq.domain, i * 32 + p);
+ generic_handle_irq(girq);
+ }
+
+ }
+
+ chained_irq_exit(ic, desc);
+}
+
+static struct irq_chip aspeed_sgpio_irqchip = {
+ .name = "aspeed-sgpio",
+ .irq_ack = aspeed_sgpio_irq_ack,
+ .irq_mask = aspeed_sgpio_irq_mask,
+ .irq_unmask = aspeed_sgpio_irq_unmask,
+ .irq_set_type = aspeed_sgpio_set_type,
+};
+
+static int aspeed_sgpio_setup_irqs(struct aspeed_sgpio *gpio,
+ struct platform_device *pdev)
+{
+ int rc, i;
+ const struct aspeed_sgpio_bank *bank;
+ struct gpio_irq_chip *irq;
+
+ rc = platform_get_irq(pdev, 0);
+ if (rc < 0)
+ return rc;
+
+ gpio->irq = rc;
+
+ /* Disable IRQ and clear Interrupt status registers for all SPGIO Pins. */
+ for (i = 0; i < ARRAY_SIZE(aspeed_sgpio_banks); i++) {
+ bank = &aspeed_sgpio_banks[i];
+ /* disable irq enable bits */
+ iowrite32(0x00000000, bank_reg(gpio, bank, reg_irq_enable));
+ /* clear status bits */
+ iowrite32(0xffffffff, bank_reg(gpio, bank, reg_irq_status));
+ }
+
+ irq = &gpio->chip.irq;
+ irq->chip = &aspeed_sgpio_irqchip;
+ irq->handler = handle_bad_irq;
+ irq->default_type = IRQ_TYPE_NONE;
+ irq->parent_handler = aspeed_sgpio_irq_handler;
+ irq->parent_handler_data = gpio;
+ irq->parents = &gpio->irq;
+ irq->num_parents = 1;
+
+ /* set IRQ settings and Enable Interrupt */
+ for (i = 0; i < ARRAY_SIZE(aspeed_sgpio_banks); i++) {
+ bank = &aspeed_sgpio_banks[i];
+ /* set falling or level-low irq */
+ iowrite32(0x00000000, bank_reg(gpio, bank, reg_irq_type0));
+ /* trigger type is edge */
+ iowrite32(0x00000000, bank_reg(gpio, bank, reg_irq_type1));
+ /* dual edge trigger mode. */
+ iowrite32(0xffffffff, bank_reg(gpio, bank, reg_irq_type2));
+ /* enable irq */
+ iowrite32(0xffffffff, bank_reg(gpio, bank, reg_irq_enable));
+ }
+
+ return 0;
+}
+
+static const struct of_device_id aspeed_sgpio_of_table[] = {
+ { .compatible = "aspeed,ast2400-sgpio" },
+ { .compatible = "aspeed,ast2500-sgpio" },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, aspeed_sgpio_of_table);
+
+static int __init aspeed_sgpio_probe(struct platform_device *pdev)
+{
+ struct aspeed_sgpio *gpio;
+ u32 nr_gpios, sgpio_freq, sgpio_clk_div;
+ int rc;
+ unsigned long apb_freq;
+
+ 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);
+
+ rc = of_property_read_u32(pdev->dev.of_node, "ngpios", &nr_gpios);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Could not read ngpios property\n");
+ return -EINVAL;
+ } else if (nr_gpios > MAX_NR_SGPIO) {
+ dev_err(&pdev->dev, "Number of GPIOs exceeds the maximum of %d: %d\n",
+ MAX_NR_SGPIO, nr_gpios);
+ return -EINVAL;
+ }
+
+ rc = of_property_read_u32(pdev->dev.of_node, "bus-frequency", &sgpio_freq);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Could not read bus-frequency property\n");
+ return -EINVAL;
+ }
+
+ gpio->pclk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(gpio->pclk)) {
+ dev_err(&pdev->dev, "devm_clk_get failed\n");
+ return PTR_ERR(gpio->pclk);
+ }
+
+ apb_freq = clk_get_rate(gpio->pclk);
+
+ /*
+ * From the datasheet,
+ * SGPIO period = 1/PCLK * 2 * (GPIO254[31:16] + 1)
+ * period = 2 * (GPIO254[31:16] + 1) / PCLK
+ * frequency = 1 / (2 * (GPIO254[31:16] + 1) / PCLK)
+ * frequency = PCLK / (2 * (GPIO254[31:16] + 1))
+ * frequency * 2 * (GPIO254[31:16] + 1) = PCLK
+ * GPIO254[31:16] = PCLK / (frequency * 2) - 1
+ */
+ if (sgpio_freq == 0)
+ return -EINVAL;
+
+ sgpio_clk_div = (apb_freq / (sgpio_freq * 2)) - 1;
+
+ if (sgpio_clk_div > (1 << 16) - 1)
+ return -EINVAL;
+
+ iowrite32(FIELD_PREP(ASPEED_SGPIO_CLK_DIV_MASK, sgpio_clk_div) |
+ FIELD_PREP(ASPEED_SGPIO_PINS_MASK, (nr_gpios / 8)) |
+ ASPEED_SGPIO_ENABLE,
+ gpio->base + ASPEED_SGPIO_CTRL);
+
+ spin_lock_init(&gpio->lock);
+
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.ngpio = nr_gpios;
+ gpio->chip.direction_input = aspeed_sgpio_dir_in;
+ gpio->chip.direction_output = aspeed_sgpio_dir_out;
+ gpio->chip.get_direction = aspeed_sgpio_get_direction;
+ gpio->chip.request = NULL;
+ gpio->chip.free = NULL;
+ gpio->chip.get = aspeed_sgpio_get;
+ gpio->chip.set = aspeed_sgpio_set;
+ gpio->chip.set_config = NULL;
+ 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);
+ if (rc < 0)
+ return rc;
+
+ return 0;
+}
+
+static struct platform_driver aspeed_sgpio_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = aspeed_sgpio_of_table,
+ },
+};
+
+module_platform_driver_probe(aspeed_sgpio_driver, aspeed_sgpio_probe);
+MODULE_DESCRIPTION("Aspeed Serial GPIO Driver");
+MODULE_LICENSE("GPL");