Re: [PATCH v3 1/2] gpio: loongson: add dts/acpi gpio support

From: Yinbo Zhu
Date: Wed Nov 16 2022 - 20:46:49 EST




在 2022/11/16 下午6:03, Qing Zhang 写道:
Hi, yinbo

On 2022/11/16 下午2:53, Yinbo Zhu wrote:
The latest Loongson series platform use dts or acpi framework to
register gpio device resources, such as the Loongson-2 series
SoC of LOONGARCH architecture. In order to support dts, acpi and
compatibility with previous platform device resources in driver,
this patch was added.

Signed-off-by: lvjianmin <lvjianmin@xxxxxxxxxxx>
Signed-off-by: zhanghongchen <zhanghongchen@xxxxxxxxxxx>
Signed-off-by: Liu Peibao <liupeibao@xxxxxxxxxxx>
Signed-off-by: Juxin Gao <gaojuxin@xxxxxxxxxxx>
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
---
Change in v3:
        1. Move the gpio platform data struct from arch/ into include/linux/
           platform_data/.
        2. Replace platform_gpio_data with loongson_gpio_platform_data in .c.
        3. Add maintainer in MAINTAINERS file for include/linux/platform_data/
           gpio-loongson.h and gpio-loongson.c
Change in v2:
        1. Fixup of_loongson_gpio_get_props and remove the parse logic about
               "loongson,conf_offset", "loongson,out_offset", "loongson,in_offset",
           "loongson,gpio_base", "loongson,support_irq" then kernel driver will
           initial them that depend compatible except "loongson,gpio_base".

  MAINTAINERS                                 |   8 +
  drivers/gpio/Kconfig                        |   6 +-
  drivers/gpio/gpio-loongson.c                | 424 ++++++++++++++++----
  include/linux/platform_data/gpio-loongson.h |  22 +
  4 files changed, 385 insertions(+), 75 deletions(-)
  create mode 100644 include/linux/platform_data/gpio-loongson.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 5114db9c8f32..bbd7a0d946eb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12051,6 +12051,14 @@ S:    Maintained
  F: Documentation/devicetree/bindings/hwinfo/loongson,ls2k-chipid.yaml
  F:    drivers/soc/loongson/loongson2_guts.c
+LOONGSON SERIES GPIO DRIVER
+M:    Huacai Chen <chenhuacai@xxxxxxxxxx>
+M:    Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+L:    linux-gpio@xxxxxxxxxxxxxxx
+S:    Maintained
+F:    drivers/gpio/gpio-loongson.c
+F:    include/linux/platform_data/gpio-loongson.h
+
  LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
  M:    Sathya Prakash <sathya.prakash@xxxxxxxxxxxx>
  M:    Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index a01af1180616..fb8f0075a8ae 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -376,10 +376,10 @@ config GPIO_LOGICVC
        programmable logic block.
  config GPIO_LOONGSON
-    bool "Loongson-2/3 GPIO support"
-    depends on CPU_LOONGSON2EF || CPU_LOONGSON64
+    bool "Loongson series GPIO support"
+    depends on CPU_LOONGSON2EF || CPU_LOONGSON64 || LOONGARCH
I did not see the dts file related to mips (eg: 2K1000),
If there is no plan to support or validate them, I recommend delete "cpu_loongson64".

Thanks,
- Qing
in fact, I have verified about 2k, but I don't plan add dts for mips.
and mips was use legacy platform driver but need add a gpio device
driver to register device. for legacy platform if someone uses it, add
it. and I will adopt your advice to delete "cpu_loongson64".

Tks,
Yinbo.
      help
-      Driver for GPIO functionality on Loongson-2F/3A/3B processors.
+      Driver for GPIO functionality on Loongson seires processors.
  config GPIO_LPC18XX
      tristate "NXP LPC18XX/43XX GPIO support"
diff --git a/drivers/gpio/gpio-loongson.c b/drivers/gpio/gpio-loongson.c
index a42145873cc9..1e553db03cf8 100644
--- a/drivers/gpio/gpio-loongson.c
+++ b/drivers/gpio/gpio-loongson.c
@@ -1,13 +1,15 @@
  // SPDX-License-Identifier: GPL-2.0-or-later
  /*
- *  Loongson-2F/3A/3B GPIO Support
+ *  Loongson Series GPIO Support
   *
- *  Copyright (c) 2008 Richard Liu,  STMicroelectronics <richard.liu@xxxxxx>
+ *  Copyright (c) 2008 Richard Liu, STMicroelectronics <richard.liu@xxxxxx>
   *  Copyright (c) 2008-2010 Arnaud Patard <apatard@xxxxxxxxxxxx>
   *  Copyright (c) 2013 Hongbing Hu <huhb@xxxxxxxxxx>
   *  Copyright (c) 2014 Huacai Chen <chenhc@xxxxxxxxxx>
+ *  Copyright (c) 2022-2023 Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
   */
+#include <linux/acpi.h>
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/module.h>
@@ -16,120 +18,398 @@
  #include <linux/gpio/driver.h>
  #include <linux/platform_device.h>
  #include <linux/bitops.h>
+#include <linux/platform_data/gpio-loongson.h>
  #include <asm/types.h>
-#include <loongson.h>
-
-#define STLS2F_N_GPIO        4
-#define STLS3A_N_GPIO        16
-
-#ifdef CONFIG_CPU_LOONGSON64
-#define LOONGSON_N_GPIO    STLS3A_N_GPIO
+#if defined(CONFIG_LOONGARCH)
+#include <asm/loongson.h>
+#elif defined(CONFIG_CPU_LOONGSON2EF)
+#include <asm/mach-loongson2ef/loongson.h>
  #else
-#define LOONGSON_N_GPIO    STLS2F_N_GPIO
+#include <asm/mach-loongson64/loongson.h>
  #endif
-/*
- * Offset into the register where we read lines, we write them from offset 0.
- * This offset is the only thing that stand between us and using
- * GPIO_GENERIC.
- */
-#define LOONGSON_GPIO_IN_OFFSET    16
+#define LOONGSON_GPIO_IN(x)        (x->base + x->in_offset)
+#define LOONGSON_GPIO_OUT(x)        (x->base + x->out_offset)
+#define LOONGSON_GPIO_OEN(x)        (x->base + x->conf_offset)
+
+#define LOONGSON_GPIO_IN_BYTE(x, gpio)    (x->base +\
+                    x->in_offset + gpio)
+#define LOONGSON_GPIO_OUT_BYTE(x, gpio)    (x->base +\
+                    x->out_offset + gpio)
+#define LOONGSON_GPIO_OEN_BYTE(x, gpio)    (x->base +\
+                    x->conf_offset + gpio)
+
+struct loongson_gpio_chip {
+    struct gpio_chip    chip;
+    spinlock_t        lock;
+    void __iomem        *base;
+    int            conf_offset;
+    int            out_offset;
+    int            in_offset;
+    u16            *gsi_idx_map;
+    u16            mapsize;
+    bool            support_irq;
+};
+
+static int loongson_gpio_request(
+            struct gpio_chip *chip, unsigned int pin)
+{
+    if (pin >= chip->ngpio)
+        return -EINVAL;
+    else
+        return 0;
+}
+
+static inline void __set_direction(struct loongson_gpio_chip *lgpio,
+            unsigned int pin, int input)
+{
+    u64 qval;
+    u8  bval;
+
+    if (!strcmp(lgpio->chip.label, "loongson,ls2k-gpio")) {
+        qval = readq(LOONGSON_GPIO_OEN(lgpio));
+        if (input)
+            qval |= 1ULL << pin;
+        else
+            qval &= ~(1ULL << pin);
+        writeq(qval, LOONGSON_GPIO_OEN(lgpio));
+        return;
+    }
-static DEFINE_SPINLOCK(gpio_lock);
+    if (!strcmp(lgpio->chip.label, "loongson,ls7a-gpio") ||
+            !strncmp(lgpio->chip.label, "LOON0002", 8)) {
+        if (input)
+            bval = 1;
+        else
+            bval = 0;
+        writeb(bval, LOONGSON_GPIO_OEN_BYTE(lgpio, pin));
+        return;
+    }
+
+    if (!strcmp(lgpio->chip.label, "loongson,platform-gpio")) {
+        if (input)
+            LOONGSON_GPIOIE |= BIT(pin);
+        else
+            LOONGSON_GPIOIE &= ~BIT(pin);
+        return;
+    }
+}
-static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+static void __set_level(struct loongson_gpio_chip *lgpio, unsigned int pin,
+            int high)
  {
-    u32 val;
+    u64 qval;
+    u8 bval;
+
+    if (!strcmp(lgpio->chip.label, "loongson,ls2k-gpio")) {
+        qval = readq(LOONGSON_GPIO_OUT(lgpio));
+        if (high)
+            qval |= 1ULL << pin;
+        else
+            qval &= ~(1ULL << pin);
+        writeq(qval, LOONGSON_GPIO_OUT(lgpio));
+        return;
+    }
-    spin_lock(&gpio_lock);
-    val = LOONGSON_GPIODATA;
-    spin_unlock(&gpio_lock);
+    if (!strcmp(lgpio->chip.label, "loongson,ls7a-gpio") ||
+            !strncmp(lgpio->chip.label, "LOON0002", 8)) {
+        if (high)
+            bval = 1;
+        else
+            bval = 0;
+        writeb(bval, LOONGSON_GPIO_OUT_BYTE(lgpio, pin));
+        return;
+    }
-    return !!(val & BIT(gpio + LOONGSON_GPIO_IN_OFFSET));
+    if (!strcmp(lgpio->chip.label, "loongson,platform-gpio")) {
+        if (LOONGSON_GPIODATA)
+            LOONGSON_GPIODATA |= BIT(pin);
+        else
+            LOONGSON_GPIODATA &= ~BIT(pin);
+        return;
+    }
  }
-static void loongson_gpio_set_value(struct gpio_chip *chip,
-        unsigned gpio, int value)
+static int loongson_gpio_direction_input(
+                struct gpio_chip *chip, unsigned int pin)
  {
-    u32 val;
+    unsigned long flags;
+    struct loongson_gpio_chip *lgpio =
+        container_of(chip, struct loongson_gpio_chip, chip);
-    spin_lock(&gpio_lock);
-    val = LOONGSON_GPIODATA;
-    if (value)
-        val |= BIT(gpio);
-    else
-        val &= ~BIT(gpio);
-    LOONGSON_GPIODATA = val;
-    spin_unlock(&gpio_lock);
+    spin_lock_irqsave(&lgpio->lock, flags);
+    __set_direction(lgpio, pin, 1);
+    spin_unlock_irqrestore(&lgpio->lock, flags);
+
+    return 0;
  }
-static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+static int loongson_gpio_direction_output(
+                struct gpio_chip *chip, unsigned int pin,
+                int value)
  {
-    u32 temp;
+    struct loongson_gpio_chip *lgpio =
+        container_of(chip, struct loongson_gpio_chip, chip);
+    unsigned long flags;
-    spin_lock(&gpio_lock);
-    temp = LOONGSON_GPIOIE;
-    temp |= BIT(gpio);
-    LOONGSON_GPIOIE = temp;
-    spin_unlock(&gpio_lock);
+    spin_lock_irqsave(&lgpio->lock, flags);
+    __set_level(lgpio, pin, value);
+    __set_direction(lgpio, pin, 0);
+    spin_unlock_irqrestore(&lgpio->lock, flags);
      return 0;
  }
-static int loongson_gpio_direction_output(struct gpio_chip *chip,
-        unsigned gpio, int level)
+static int loongson_gpio_get(struct gpio_chip *chip, unsigned int pin)
+{
+    u64 qval;
+    u8  bval;
+    int val;
+    struct loongson_gpio_chip *lgpio =
+        container_of(chip, struct loongson_gpio_chip, chip);
+
+    if (!strcmp(lgpio->chip.label, "loongson,ls2k-gpio")) {
+        qval = readq(LOONGSON_GPIO_IN(lgpio));
+        return ((qval & (1ULL << pin)) != 0);
+    }
+
+    if (!strcmp(lgpio->chip.label, "loongson,ls7a-gpio") ||
+            !strncmp(lgpio->chip.label, "LOON0002", 8)) {
+        bval = readb(LOONGSON_GPIO_IN_BYTE(lgpio, pin));
+        return (bval & 1);
+    }
+
+    if (!strcmp(lgpio->chip.label, "loongson,platform-gpio")) {
+        val = LOONGSON_GPIODATA;
+        return !!(val & BIT(pin + lgpio->in_offset));
+    }
+
+    return -ENXIO;
+}
+
+static void loongson_gpio_set(struct gpio_chip *chip, unsigned int pin,
+            int value)
  {
-    u32 temp;
+    unsigned long flags;
+    struct loongson_gpio_chip *lgpio =
+        container_of(chip, struct loongson_gpio_chip, chip);
-    loongson_gpio_set_value(chip, gpio, level);
-    spin_lock(&gpio_lock);
-    temp = LOONGSON_GPIOIE;
-    temp &= ~BIT(gpio);
-    LOONGSON_GPIOIE = temp;
-    spin_unlock(&gpio_lock);
+    spin_lock_irqsave(&lgpio->lock, flags);
+    __set_level(lgpio, pin, value);
+    spin_unlock_irqrestore(&lgpio->lock, flags);
+}
+
+static int loongson_gpio_to_irq(
+            struct gpio_chip *chip, unsigned int offset)
+{
+    struct platform_device *pdev =
+        container_of(chip->parent, struct platform_device, dev);
+    struct loongson_gpio_chip *lgpio =
+        container_of(chip, struct loongson_gpio_chip, chip);
+
+    if (offset >= chip->ngpio)
+        return -EINVAL;
+
+    if ((lgpio->gsi_idx_map != NULL) && (offset < lgpio->mapsize))
+        offset = lgpio->gsi_idx_map[offset];
+
+    return platform_get_irq(pdev, offset);
+}
+
+static int loongson_gpio_init(
+            struct device *dev, struct loongson_gpio_chip *lgpio,
+            struct device_node *np, void __iomem *base)
+{
+    lgpio->chip.request = loongson_gpio_request;
+    lgpio->chip.direction_input = loongson_gpio_direction_input;
+    lgpio->chip.get = loongson_gpio_get;
+    lgpio->chip.direction_output = loongson_gpio_direction_output;
+    lgpio->chip.set = loongson_gpio_set;
+    lgpio->chip.can_sleep = 0;
+    lgpio->chip.of_node = np;
+    lgpio->chip.parent = dev;
+    spin_lock_init(&lgpio->lock);
+    lgpio->base = (void __iomem *)base;
+
+    if (!strcmp(lgpio->chip.label, "loongson,ls7a-gpio") ||
+            !strncmp(lgpio->chip.label, "LOON0002", 8) ||
+            !strcmp(lgpio->chip.label, "loongson,ls2k-gpio"))
+        lgpio->chip.to_irq = loongson_gpio_to_irq;
+
+    gpiochip_add(&lgpio->chip);
      return 0;
  }
+static void of_loongson_gpio_get_props(struct device_node *np,
+                  struct loongson_gpio_chip *lgpio)
+{
+    const char *name;
+
+    of_property_read_u32(np, "ngpios", (u32 *)&lgpio->chip.ngpio);
+
+    of_property_read_string(np, "compatible", &name);
+    lgpio->chip.label = kstrdup(name, GFP_KERNEL);
+
+    if (!strcmp(name, "loongson,ls2k-gpio")) {
+        lgpio->support_irq = true;
+        lgpio->conf_offset = 0x0;
+        lgpio->out_offset = 0x10;
+        lgpio->in_offset = 0x20;
+        return;
+    }
+
+    if (!strcmp(name, "loongson,ls7a-gpio")) {
+        lgpio->support_irq = true;
+        lgpio->conf_offset = 0x800;
+        lgpio->out_offset = 0x900;
+        lgpio->in_offset = 0xa00;
+        return;
+    }
+}
+
+static void acpi_loongson_gpio_get_props(struct platform_device *pdev,
+                  struct loongson_gpio_chip *lgpio)
+{
+
+    struct device *dev = &pdev->dev;
+    int rval;
+
+    device_property_read_u32(dev, "ngpios", (u32 *)&lgpio->chip.ngpio);
+    device_property_read_u32(dev, "gpio_base", (u32 *)&lgpio->chip.base);
+    device_property_read_u32(dev, "conf_offset",
+                    (u32 *)&lgpio->conf_offset);
+    device_property_read_u32(dev, "out_offset",
+                    (u32 *)&lgpio->out_offset);
+    device_property_read_u32(dev, "in_offset", (u32 *)&lgpio->in_offset);
+
+    rval = device_property_read_u16_array(dev, "gsi_idx_map", NULL, 0);
+    if (rval > 0) {
+        lgpio->gsi_idx_map =
+            kmalloc_array(rval, sizeof(*lgpio->gsi_idx_map),
+                    GFP_KERNEL);
+        if (unlikely(!lgpio->gsi_idx_map)) {
+            dev_err(dev, "Alloc gsi_idx_map fail!\n");
+        } else {
+            lgpio->mapsize = rval;
+            device_property_read_u16_array(dev, "gsi_idx_map",
+                    lgpio->gsi_idx_map, lgpio->mapsize);
+        }
+    }
+
+    lgpio->chip.label = kstrdup(pdev->name, GFP_KERNEL);
+}
+
+static void platform_loongson_gpio_get_props(struct platform_device *pdev,
+                  struct loongson_gpio_chip *lgpio)
+{
+    struct loongson_gpio_platform_data *gpio_data =
+        (struct loongson_gpio_platform_data *)pdev->dev.platform_data;
+
+    lgpio->chip.ngpio = gpio_data->ngpio;
+    lgpio->chip.base = gpio_data->gpio_base;
+    lgpio->conf_offset = gpio_data->gpio_conf;
+    lgpio->out_offset = gpio_data->gpio_out;
+    lgpio->in_offset = gpio_data->gpio_in;
+    lgpio->chip.label = kstrdup(gpio_data->label, GFP_KERNEL);
+}
+
  static int loongson_gpio_probe(struct platform_device *pdev)
  {
-    struct gpio_chip *gc;
+    struct resource *iores;
+    void __iomem *base;
+    struct loongson_gpio_chip *lgpio;
+    struct device_node *np = pdev->dev.of_node;
      struct device *dev = &pdev->dev;
+    int ret = 0;
-    gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
-    if (!gc)
+    lgpio = kzalloc(sizeof(struct loongson_gpio_chip), GFP_KERNEL);
+    if (!lgpio)
          return -ENOMEM;
-    gc->label = "loongson-gpio-chip";
-    gc->base = 0;
-    gc->ngpio = LOONGSON_N_GPIO;
-    gc->get = loongson_gpio_get_value;
-    gc->set = loongson_gpio_set_value;
-    gc->direction_input = loongson_gpio_direction_input;
-    gc->direction_output = loongson_gpio_direction_output;
+    if (np)
+        of_loongson_gpio_get_props(np, lgpio);
+    else if (ACPI_COMPANION(&pdev->dev))
+        acpi_loongson_gpio_get_props(pdev, lgpio);
+    else
+        platform_loongson_gpio_get_props(pdev, lgpio);
+
+    iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+    if (!iores) {
+        ret = -ENODEV;
+        goto out;
+    }
+
+    if (!request_mem_region(iores->start, resource_size(iores),
+                pdev->name)) {
+        ret = -EBUSY;
+        goto out;
+    }
+
+    base = ioremap(iores->start, resource_size(iores));
+    if (!base) {
+        ret = -ENOMEM;
+        goto out;
+    }
+
+    platform_set_drvdata(pdev, lgpio);
+
+    loongson_gpio_init(dev, lgpio, np, base);
+
+    return 0;
+out:
+    pr_err("%s: %s: missing mandatory property\n", __func__, np->name);
+    return ret;
+}
+
+static int loongson_gpio_remove(struct platform_device *pdev)
+{
+    struct loongson_gpio_chip *lgpio = platform_get_drvdata(pdev);
+    struct resource        *mem;
+
+    platform_set_drvdata(pdev, NULL);
-    return gpiochip_add_data(gc, NULL);
+    gpiochip_remove(&lgpio->chip);
+    iounmap(lgpio->base);
+    kfree(lgpio->gsi_idx_map);
+    kfree(lgpio);
+    mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+    release_mem_region(mem->start, resource_size(mem));
+
+    return 0;
  }
+static const struct of_device_id loongson_gpio_dt_ids[] = {
+    { .compatible = "loongson,ls2k-gpio"},
+    { .compatible = "loongson,ls7a-gpio"},
+    {}
+};
+MODULE_DEVICE_TABLE(of, loongson_gpio_dt_ids);
+
+static const struct acpi_device_id loongson_gpio_acpi_match[] = {
+    {"LOON0002"},
+    {}
+};
+MODULE_DEVICE_TABLE(acpi, loongson_gpio_acpi_match);
+
  static struct platform_driver loongson_gpio_driver = {
      .driver = {
          .name = "loongson-gpio",
+        .owner = THIS_MODULE,
+        .of_match_table = loongson_gpio_dt_ids,
+        .acpi_match_table = ACPI_PTR(loongson_gpio_acpi_match),
      },
      .probe = loongson_gpio_probe,
+    .remove = loongson_gpio_remove,
  };
  static int __init loongson_gpio_setup(void)
  {
-    struct platform_device *pdev;
-    int ret;
-
-    ret = platform_driver_register(&loongson_gpio_driver);
-    if (ret) {
-        pr_err("error registering loongson GPIO driver\n");
-        return ret;
-    }
-
-    pdev = platform_device_register_simple("loongson-gpio", -1, NULL, 0);
-    return PTR_ERR_OR_ZERO(pdev);
+    return platform_driver_register(&loongson_gpio_driver);
  }
  postcore_initcall(loongson_gpio_setup);
+
+static void __exit loongson_gpio_exit(void)
+{
+    platform_driver_unregister(&loongson_gpio_driver);
+}
diff --git a/include/linux/platform_data/gpio-loongson.h b/include/linux/platform_data/gpio-loongson.h
new file mode 100644
index 000000000000..f102d2650576
--- /dev/null
+++ b/include/linux/platform_data/gpio-loongson.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Author: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+
+#ifndef __LOONGSON_GPIO_PLATFORM_H
+#define __LOONGSON_GPIO_PLATFORM_H
+
+/* ============== Data structrues =============== */
+
+struct loongson_gpio_platform_data {
+    u32 gpio_conf;
+    u32 gpio_out;
+    u32 gpio_in;
+    u32 support_irq;
+    char *label;
+    int gpio_base;
+    int ngpio;
+};
+
+#endif