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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpio/gpio-hlwd.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpio/gpio-hlwd.c')
-rw-r--r--drivers/gpio/gpio-hlwd.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-hlwd.c b/drivers/gpio/gpio-hlwd.c
new file mode 100644
index 000000000..4e13e937f
--- /dev/null
+++ b/drivers/gpio/gpio-hlwd.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (C) 2008-2009 The GameCube Linux Team
+// Copyright (C) 2008,2009 Albert Herranz
+// Copyright (C) 2017-2018 Jonathan Neuschäfer
+//
+// Nintendo Wii (Hollywood) GPIO driver
+
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+
+/*
+ * Register names and offsets courtesy of WiiBrew:
+ * https://wiibrew.org/wiki/Hardware/Hollywood_GPIOs
+ *
+ * Note that for most registers, there are two versions:
+ * - HW_GPIOB_* Is always accessible by the Broadway PowerPC core, but does
+ * always give access to all GPIO lines
+ * - HW_GPIO_* Is only accessible by the Broadway PowerPC code if the memory
+ * firewall (AHBPROT) in the Hollywood chipset has been configured to allow
+ * such access.
+ *
+ * The ownership of each GPIO line can be configured in the HW_GPIO_OWNER
+ * register: A one bit configures the line for access via the HW_GPIOB_*
+ * registers, a zero bit indicates access via HW_GPIO_*. This driver uses
+ * HW_GPIOB_*.
+ */
+#define HW_GPIOB_OUT 0x00
+#define HW_GPIOB_DIR 0x04
+#define HW_GPIOB_IN 0x08
+#define HW_GPIOB_INTLVL 0x0c
+#define HW_GPIOB_INTFLAG 0x10
+#define HW_GPIOB_INTMASK 0x14
+#define HW_GPIOB_INMIR 0x18
+#define HW_GPIO_ENABLE 0x1c
+#define HW_GPIO_OUT 0x20
+#define HW_GPIO_DIR 0x24
+#define HW_GPIO_IN 0x28
+#define HW_GPIO_INTLVL 0x2c
+#define HW_GPIO_INTFLAG 0x30
+#define HW_GPIO_INTMASK 0x34
+#define HW_GPIO_INMIR 0x38
+#define HW_GPIO_OWNER 0x3c
+
+struct hlwd_gpio {
+ struct gpio_chip gpioc;
+ struct irq_chip irqc;
+ void __iomem *regs;
+ int irq;
+ u32 edge_emulation;
+ u32 rising_edge, falling_edge;
+};
+
+static void hlwd_gpio_irqhandler(struct irq_desc *desc)
+{
+ struct hlwd_gpio *hlwd =
+ gpiochip_get_data(irq_desc_get_handler_data(desc));
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ unsigned long flags;
+ unsigned long pending;
+ int hwirq;
+ u32 emulated_pending;
+
+ raw_spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags);
+ pending = ioread32be(hlwd->regs + HW_GPIOB_INTFLAG);
+ pending &= ioread32be(hlwd->regs + HW_GPIOB_INTMASK);
+
+ /* Treat interrupts due to edge trigger emulation separately */
+ emulated_pending = hlwd->edge_emulation & pending;
+ pending &= ~emulated_pending;
+ if (emulated_pending) {
+ u32 level, rising, falling;
+
+ level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL);
+ rising = level & emulated_pending;
+ falling = ~level & emulated_pending;
+
+ /* Invert the levels */
+ iowrite32be(level ^ emulated_pending,
+ hlwd->regs + HW_GPIOB_INTLVL);
+
+ /* Ack all emulated-edge interrupts */
+ iowrite32be(emulated_pending, hlwd->regs + HW_GPIOB_INTFLAG);
+
+ /* Signal interrupts only on the correct edge */
+ rising &= hlwd->rising_edge;
+ falling &= hlwd->falling_edge;
+
+ /* Mark emulated interrupts as pending */
+ pending |= rising | falling;
+ }
+ raw_spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags);
+
+ chained_irq_enter(chip, desc);
+
+ for_each_set_bit(hwirq, &pending, 32)
+ generic_handle_domain_irq(hlwd->gpioc.irq.domain, hwirq);
+
+ chained_irq_exit(chip, desc);
+}
+
+static void hlwd_gpio_irq_ack(struct irq_data *data)
+{
+ struct hlwd_gpio *hlwd =
+ gpiochip_get_data(irq_data_get_irq_chip_data(data));
+
+ iowrite32be(BIT(data->hwirq), hlwd->regs + HW_GPIOB_INTFLAG);
+}
+
+static void hlwd_gpio_irq_mask(struct irq_data *data)
+{
+ struct hlwd_gpio *hlwd =
+ gpiochip_get_data(irq_data_get_irq_chip_data(data));
+ unsigned long flags;
+ u32 mask;
+
+ raw_spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags);
+ mask = ioread32be(hlwd->regs + HW_GPIOB_INTMASK);
+ mask &= ~BIT(data->hwirq);
+ iowrite32be(mask, hlwd->regs + HW_GPIOB_INTMASK);
+ raw_spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags);
+}
+
+static void hlwd_gpio_irq_unmask(struct irq_data *data)
+{
+ struct hlwd_gpio *hlwd =
+ gpiochip_get_data(irq_data_get_irq_chip_data(data));
+ unsigned long flags;
+ u32 mask;
+
+ raw_spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags);
+ mask = ioread32be(hlwd->regs + HW_GPIOB_INTMASK);
+ mask |= BIT(data->hwirq);
+ iowrite32be(mask, hlwd->regs + HW_GPIOB_INTMASK);
+ raw_spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags);
+}
+
+static void hlwd_gpio_irq_enable(struct irq_data *data)
+{
+ hlwd_gpio_irq_ack(data);
+ hlwd_gpio_irq_unmask(data);
+}
+
+static void hlwd_gpio_irq_setup_emulation(struct hlwd_gpio *hlwd, int hwirq,
+ unsigned int flow_type)
+{
+ u32 level, state;
+
+ /* Set the trigger level to the inactive level */
+ level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL);
+ state = ioread32be(hlwd->regs + HW_GPIOB_IN) & BIT(hwirq);
+ level &= ~BIT(hwirq);
+ level |= state ^ BIT(hwirq);
+ iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL);
+
+ hlwd->edge_emulation |= BIT(hwirq);
+ hlwd->rising_edge &= ~BIT(hwirq);
+ hlwd->falling_edge &= ~BIT(hwirq);
+ if (flow_type & IRQ_TYPE_EDGE_RISING)
+ hlwd->rising_edge |= BIT(hwirq);
+ if (flow_type & IRQ_TYPE_EDGE_FALLING)
+ hlwd->falling_edge |= BIT(hwirq);
+}
+
+static int hlwd_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+ struct hlwd_gpio *hlwd =
+ gpiochip_get_data(irq_data_get_irq_chip_data(data));
+ unsigned long flags;
+ u32 level;
+
+ raw_spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags);
+
+ hlwd->edge_emulation &= ~BIT(data->hwirq);
+
+ switch (flow_type) {
+ case IRQ_TYPE_LEVEL_HIGH:
+ level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL);
+ level |= BIT(data->hwirq);
+ iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL);
+ level &= ~BIT(data->hwirq);
+ iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL);
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ case IRQ_TYPE_EDGE_FALLING:
+ case IRQ_TYPE_EDGE_BOTH:
+ hlwd_gpio_irq_setup_emulation(hlwd, data->hwirq, flow_type);
+ break;
+ default:
+ raw_spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags);
+ return -EINVAL;
+ }
+
+ raw_spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags);
+ return 0;
+}
+
+static int hlwd_gpio_probe(struct platform_device *pdev)
+{
+ struct hlwd_gpio *hlwd;
+ u32 ngpios;
+ int res;
+
+ hlwd = devm_kzalloc(&pdev->dev, sizeof(*hlwd), GFP_KERNEL);
+ if (!hlwd)
+ return -ENOMEM;
+
+ hlwd->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(hlwd->regs))
+ return PTR_ERR(hlwd->regs);
+
+ /*
+ * Claim all GPIOs using the OWNER register. This will not work on
+ * systems where the AHBPROT memory firewall hasn't been configured to
+ * permit PPC access to HW_GPIO_*.
+ *
+ * Note that this has to happen before bgpio_init reads the
+ * HW_GPIOB_OUT and HW_GPIOB_DIR, because otherwise it reads the wrong
+ * values.
+ */
+ iowrite32be(0xffffffff, hlwd->regs + HW_GPIO_OWNER);
+
+ res = bgpio_init(&hlwd->gpioc, &pdev->dev, 4,
+ hlwd->regs + HW_GPIOB_IN, hlwd->regs + HW_GPIOB_OUT,
+ NULL, hlwd->regs + HW_GPIOB_DIR, NULL,
+ BGPIOF_BIG_ENDIAN_BYTE_ORDER);
+ if (res < 0) {
+ dev_warn(&pdev->dev, "bgpio_init failed: %d\n", res);
+ return res;
+ }
+
+ res = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios);
+ if (res)
+ ngpios = 32;
+ hlwd->gpioc.ngpio = ngpios;
+
+ /* Mask and ack all interrupts */
+ iowrite32be(0, hlwd->regs + HW_GPIOB_INTMASK);
+ iowrite32be(0xffffffff, hlwd->regs + HW_GPIOB_INTFLAG);
+
+ /*
+ * If this GPIO controller is not marked as an interrupt controller in
+ * the DT, skip interrupt support.
+ */
+ if (of_property_read_bool(pdev->dev.of_node, "interrupt-controller")) {
+ struct gpio_irq_chip *girq;
+
+ hlwd->irq = platform_get_irq(pdev, 0);
+ if (hlwd->irq < 0) {
+ dev_info(&pdev->dev, "platform_get_irq returned %d\n",
+ hlwd->irq);
+ return hlwd->irq;
+ }
+
+ hlwd->irqc.name = dev_name(&pdev->dev);
+ hlwd->irqc.irq_mask = hlwd_gpio_irq_mask;
+ hlwd->irqc.irq_unmask = hlwd_gpio_irq_unmask;
+ hlwd->irqc.irq_enable = hlwd_gpio_irq_enable;
+ hlwd->irqc.irq_set_type = hlwd_gpio_irq_set_type;
+
+ girq = &hlwd->gpioc.irq;
+ girq->chip = &hlwd->irqc;
+ girq->parent_handler = hlwd_gpio_irqhandler;
+ girq->num_parents = 1;
+ girq->parents = devm_kcalloc(&pdev->dev, 1,
+ sizeof(*girq->parents),
+ GFP_KERNEL);
+ if (!girq->parents)
+ return -ENOMEM;
+ girq->parents[0] = hlwd->irq;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_level_irq;
+ }
+
+ return devm_gpiochip_add_data(&pdev->dev, &hlwd->gpioc, hlwd);
+}
+
+static const struct of_device_id hlwd_gpio_match[] = {
+ { .compatible = "nintendo,hollywood-gpio", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, hlwd_gpio_match);
+
+static struct platform_driver hlwd_gpio_driver = {
+ .driver = {
+ .name = "gpio-hlwd",
+ .of_match_table = hlwd_gpio_match,
+ },
+ .probe = hlwd_gpio_probe,
+};
+module_platform_driver(hlwd_gpio_driver);
+
+MODULE_AUTHOR("Jonathan Neuschäfer <j.neuschaefer@gmx.net>");
+MODULE_DESCRIPTION("Nintendo Wii GPIO driver");
+MODULE_LICENSE("GPL");