Re: [PATCH v4 1/2] gpio: loongson: add dts and acpi support
From: Yinbo Zhu
Date: Mon Nov 21 2022 - 07:36:45 EST
在 2022/11/17 下午5:39, Bartosz Golaszewski 写道:
On Thu, Nov 17, 2022 at 4:59 AM Yinbo Zhu <zhuyinbo@xxxxxxxxxxx> wrote:
Latest Loongson platforms such as the Loongson-2 SoC series describe
GPIO device resources with DTS or ACPI. Add such support to the
existing platform device driver.
Signed-off-by: Jianmin Lv <lvjianmin@xxxxxxxxxxx>
Signed-off-by: Hongchen Zhang <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 v4:
1. Fixup name spelling about Signed-off-by.
2. Drop "series" here and everywhere else.
3. Fixup the copyright in driver.
4. Drop the "else" in loongson_gpio_request.
5. Use trinocular operation replace the related logic.
6. Remove lable judgement in context about "lgpio->chip.to_irq =
loongson_gpio_to_irq"
7. Use dev_err replace pr_err in probe.
8. Make legacy platform_data should be left out of this patch.
9. Remove the mips config in gpio Kconfig.
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 | 403 ++++++++++++++++++++++++++++-------
3 files changed, 338 insertions(+), 79 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index 5114db9c8f32..838b920efcef 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 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..b4423c058b1d 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 LOONGARCH || COMPILE_TEST
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..b9b191a541c0 100644
--- a/drivers/gpio/gpio-loongson.c
+++ b/drivers/gpio/gpio-loongson.c
@@ -1,13 +1,11 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
+// SPDX-License-Identifier: GPL-2.0+
/*
- * Loongson-2F/3A/3B GPIO Support
+ * Loongson GPIO Support
*
- * 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>
Why are you removing other people's copyright notices?
I will add a new file.
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
*/
+#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
@@ -17,119 +15,372 @@
#include <linux/platform_device.h>
#include <linux/bitops.h>
#include <asm/types.h>
-#include <loongson.h>
+#include <asm/loongson.h>
-#define STLS2F_N_GPIO 4
-#define STLS3A_N_GPIO 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)
-#ifdef CONFIG_CPU_LOONGSON64
-#define LOONGSON_N_GPIO STLS3A_N_GPIO
-#else
-#define LOONGSON_N_GPIO STLS2F_N_GPIO
-#endif
+#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)
-/*
- * 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
+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;
+};
-static DEFINE_SPINLOCK(gpio_lock);
+static int loongson_gpio_request(
+ struct gpio_chip *chip, unsigned int pin)
+{
+ if (pin >= chip->ngpio)
+ return -EINVAL;
+
+ return 0;
+}
-static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+static inline void __set_direction(struct loongson_gpio_chip *lgpio,
+ unsigned int pin, int input)
{
- u32 val;
+ 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;
+ }
- 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)) {
This is ugly - can you instead use chip data associated with the
relevant compatible to store whatever custom info you need? See the
data field in struct of_device_id and acpi_device_id. Same elsewhere,
I really dislike this label parsing everywhere.
okay, I got it.
+ bval = input ? 1 : 0;
+ writeb(bval, LOONGSON_GPIO_OEN_BYTE(lgpio, pin));
+ return;
+ }
- return !!(val & BIT(gpio + LOONGSON_GPIO_IN_OFFSET));
+ if (!strcmp(lgpio->chip.label, "loongson,platform-gpio")) {
+ if (input)
+ LOONGSON_GPIOIE |= BIT(pin);
+ else
+ LOONGSON_GPIOIE &= ~BIT(pin);
+ return;
+ }
}
-static void loongson_gpio_set_value(struct gpio_chip *chip,
- unsigned gpio, int value)
+static void __set_level(struct loongson_gpio_chip *lgpio, unsigned int pin,
+ int high)
{
- u32 val;
+ u64 qval;
+ u8 bval;
- spin_lock(&gpio_lock);
- val = LOONGSON_GPIODATA;
- if (value)
- val |= BIT(gpio);
- else
- val &= ~BIT(gpio);
- LOONGSON_GPIODATA = val;
- spin_unlock(&gpio_lock);
+ 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;
+ }
+
+ if (!strcmp(lgpio->chip.label, "loongson,ls7a-gpio") ||
+ !strncmp(lgpio->chip.label, "LOON0002", 8)) {
+ bval = high ? 1 : 0;
+ writeb(bval, LOONGSON_GPIO_OUT_BYTE(lgpio, pin));
+ return;
+ }
+
+ if (!strcmp(lgpio->chip.label, "loongson,platform-gpio")) {
+ if (LOONGSON_GPIODATA)
+ LOONGSON_GPIODATA |= BIT(pin);
+ else
+ LOONGSON_GPIODATA &= ~BIT(pin);
+ return;
+ }
}
-static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+static int loongson_gpio_direction_input(
+ struct gpio_chip *chip, unsigned int pin)
{
- u32 temp;
+ unsigned long flags;
+ struct loongson_gpio_chip *lgpio =
+ container_of(chip, struct loongson_gpio_chip, chip);
- spin_lock(&gpio_lock);
- temp = LOONGSON_GPIOIE;
- temp |= BIT(gpio);
- LOONGSON_GPIOIE = temp;
- 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_output(struct gpio_chip *chip,
- unsigned gpio, int level)
+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;
- 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);
+ __set_direction(lgpio, pin, 0);
+ spin_unlock_irqrestore(&lgpio->lock, flags);
return 0;
}
+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)
+{
+ unsigned long flags;
+ struct loongson_gpio_chip *lgpio =
+ container_of(chip, struct loongson_gpio_chip, chip);
+
+ 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;
+ 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->conf_offset = 0x0;
+ lgpio->out_offset = 0x10;
+ lgpio->in_offset = 0x20;
+ return;
+ }
+
+ if (!strcmp(name, "loongson,ls7a-gpio")) {
+ 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)
+{
+}
Drop it, if you don't use it.
okay, I got it.
+
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);
Why stop using devres? Same elsewhere.
okay, I had use it devres.
+ 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);
I would prefer if you used generic device properties - like you
already do for acpi. They work for OF too thanks to the fwnode
abstraction.
Some of these attributes I tried to define in the dts, but they are not
generic, so I put them in xxx_ device_ id data field.
+
+ 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;
+ }
Are you aware of the gpio-regmap interface? It seems to me that this
code could benefit from using it. There are already some good examples
in the tree.
I tried to use regmap, but I found that my driver needs to access 64 bit
registers, and regmap cannot cover it.
+
+ platform_set_drvdata(pdev, lgpio);
+
+ loongson_gpio_init(dev, lgpio, np, base);
+
+ return 0;
+out:
+ dev_err(dev, "missing mandatory property\n");
+
So if request_mem_region() or ioremap() fails, we're printing this
error message? Doesn't seem right.
+ return ret;
+}
+
+static int loongson_gpio_remove(struct platform_device *pdev)
+{
+ struct loongson_gpio_chip *lgpio = platform_get_drvdata(pdev);
+ struct resource *mem;
- return gpiochip_add_data(gc, NULL);
+ platform_set_drvdata(pdev, 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));
+
This entire function can be dropped if you used devres.
+ 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);
+}
This module cannot be unloaded so you can drop this. The __exit macro
will make the compiler drop it anyway.
okay I got it.
Bart
+
+MODULE_DESCRIPTION("Loongson gpio driver");
+MODULE_LICENSE("GPL");
--
2.31.1