The output pins of the RZ/G2L general PWM timer (GPT) can be disabled
by using the port output enabling function for the GPT (POEG).
This patch adds basic support using s/w control through sysfs
to enable/disable output from GPT.
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
v4->v5:
* Updated kernel version in sysfs doc.
v3->v4:
* Updated commit description.
v2->v3:
* Added sysfs documentation for output_disable
* PWM_RZG2L_GPT implies ARCH_RZG2L. So removed ARCH_RZG2L dependency
* Used dev_get_drvdata to get device data
* Replaced sprintf->sysfs_emit in show().
v1->v2:
* Renamed the file poeg-rzg2l->rzg2l-poeg
* Removed the macro POEGG as there is only single register and
updated rzg2l_poeg_write() and rzg2l_poeg_read()
* Updated error handling in probe()
Ref->v1:
* Moved driver files from soc to pincontrol directory
* Updated KConfig
---
.../ABI/testing/sysfs-platform-rzg2l-poeg | 18 ++
drivers/pinctrl/renesas/Kconfig | 2 +
drivers/pinctrl/renesas/Makefile | 2 +
drivers/pinctrl/renesas/poeg/Kconfig | 11 ++
drivers/pinctrl/renesas/poeg/Makefile | 2 +
drivers/pinctrl/renesas/poeg/rzg2l-poeg.c | 157 ++++++++++++++++++
6 files changed, 192 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-platform-rzg2l-poeg
create mode 100644 drivers/pinctrl/renesas/poeg/Kconfig
create mode 100644 drivers/pinctrl/renesas/poeg/Makefile
create mode 100644 drivers/pinctrl/renesas/poeg/rzg2l-poeg.c
diff --git a/Documentation/ABI/testing/sysfs-platform-rzg2l-poeg b/Documentation/ABI/testing/sysfs-platform-rzg2l-poeg
new file mode 100644
index 000000000000..157c98c49940
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-platform-rzg2l-poeg
@@ -0,0 +1,18 @@
+What: /sys/devices/platform/<rzg2l-poeg's name>/output_disable
+Date: November 2022
+KernelVersion: 6.3
+Contact: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
+Description:
+ This file can be read and write.
+ The file used to control the output disable using
+ register settings.
+
+ Write the following string to control the output disable:
+
+ - "1" - request output-disable from software.
+ - "0" - request no output-disable from software.
+
+ Read the file, then it shows the following strings:
+
+ - "1" - Output-disable request from software occurred.
+ - "0" - No output-disable request from software occurred.
diff --git a/drivers/pinctrl/renesas/Kconfig b/drivers/pinctrl/renesas/Kconfig
index 0903a0a41831..92bdc2e1e125 100644
--- a/drivers/pinctrl/renesas/Kconfig
+++ b/drivers/pinctrl/renesas/Kconfig
@@ -308,4 +308,6 @@ config PINCTRL_PFC_SHX3
bool "pin control support for SH-X3" if COMPILE_TEST
select PINCTRL_SH_FUNC_GPIO
+source "drivers/pinctrl/renesas/poeg/Kconfig"
+
endmenu
diff --git a/drivers/pinctrl/renesas/Makefile b/drivers/pinctrl/renesas/Makefile
index 558b30ce0dec..de1bb592fbf3 100644
--- a/drivers/pinctrl/renesas/Makefile
+++ b/drivers/pinctrl/renesas/Makefile
@@ -52,6 +52,8 @@ obj-$(CONFIG_PINCTRL_RZG2L) += pinctrl-rzg2l.o
obj-$(CONFIG_PINCTRL_RZN1) += pinctrl-rzn1.o
obj-$(CONFIG_PINCTRL_RZV2M) += pinctrl-rzv2m.o
+obj-$(CONFIG_POEG_RZG2L) += poeg/
+
ifeq ($(CONFIG_COMPILE_TEST),y)
CFLAGS_pfc-sh7203.o += -I$(srctree)/arch/sh/include/cpu-sh2a
CFLAGS_pfc-sh7264.o += -I$(srctree)/arch/sh/include/cpu-sh2a
diff --git a/drivers/pinctrl/renesas/poeg/Kconfig b/drivers/pinctrl/renesas/poeg/Kconfig
new file mode 100644
index 000000000000..306e8ae81cb2
--- /dev/null
+++ b/drivers/pinctrl/renesas/poeg/Kconfig
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0
+config POEG_RZG2L
+ tristate "Renesas RZ/G2L poeg support"
+ depends on PWM_RZG2L_GPT || COMPILE_TEST
+ depends on HAS_IOMEM
+ help
+ This driver exposes the Port Output Enable for GPT(POEG) found
+ in Renesas RZ/G2L alike SoCs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called rzg2l-poeg.
diff --git a/drivers/pinctrl/renesas/poeg/Makefile b/drivers/pinctrl/renesas/poeg/Makefile
new file mode 100644
index 000000000000..610bdd6182be
--- /dev/null
+++ b/drivers/pinctrl/renesas/poeg/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_POEG_RZG2L) += rzg2l-poeg.o
diff --git a/drivers/pinctrl/renesas/poeg/rzg2l-poeg.c b/drivers/pinctrl/renesas/poeg/rzg2l-poeg.c
new file mode 100644
index 000000000000..3788191bc2f1
--- /dev/null
+++ b/drivers/pinctrl/renesas/poeg/rzg2l-poeg.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/G2L Port Output Enable for GPT (POEG) driver
+ *
+ * Copyright (C) 2022 Renesas Electronics Corporation
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+
+#define POEGG_SSF BIT(3)
+
+struct rzg2l_poeg_chip {
+ struct reset_control *rstc;
+ void __iomem *mmio;
+};
+
+static void rzg2l_poeg_write(struct rzg2l_poeg_chip *chip, u32 data)
+{
+ iowrite32(data, chip->mmio);
+}
+
+static u32 rzg2l_poeg_read(struct rzg2l_poeg_chip *chip)
+{
+ return ioread32(chip->mmio);
+}
+
+static ssize_t output_disable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct rzg2l_poeg_chip *chip;
+ unsigned int val;
+ u32 reg_val;
+ int ret;
+
+ chip = dev_get_drvdata(dev);
+ ret = kstrtouint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ reg_val = rzg2l_poeg_read(chip);
+ if (val)
+ reg_val |= POEGG_SSF;
+ else
+ reg_val &= ~POEGG_SSF;
+
+ rzg2l_poeg_write(chip, reg_val);
+
+ return count;
+}
+
+static ssize_t output_disable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct rzg2l_poeg_chip *chip;
+ u32 reg;
+
+ chip = dev_get_drvdata(dev);
+ reg = rzg2l_poeg_read(chip);
+
+ return sysfs_emit(buf, "%u\n", (reg & POEGG_SSF) ? 1 : 0);
+}
+
+static DEVICE_ATTR_RW(output_disable);
+
+static struct attribute *poeg_attrs[] = {
+ &dev_attr_output_disable.attr,
+ NULL,
+};
+
+static const struct attribute_group poeg_groups = {
+ .attrs = poeg_attrs,
+};
+
+static const struct of_device_id rzg2l_poeg_of_table[] = {
+ { .compatible = "renesas,rzg2l-poeg", },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rzg2l_poeg_of_table);
+
+static int rzg2l_poeg_probe(struct platform_device *pdev)
+{
+ struct rzg2l_poeg_chip *chip;
+ int ret;
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->mmio = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(chip->mmio))
+ return PTR_ERR(chip->mmio);
+
+ chip->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(chip->rstc))
+ return dev_err_probe(&pdev->dev, PTR_ERR(chip->rstc),
+ "get reset failed\n");
+
+ ret = reset_control_deassert(chip->rstc);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, chip);
+ pm_runtime_enable(&pdev->dev);
+ ret = pm_runtime_resume_and_get(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
+ goto err_pm_disable;
+ }
+
+ ret = sysfs_create_group(&pdev->dev.kobj, &poeg_groups);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to create sysfs: %d\n", ret);
+ goto err_pm;
+ }
+
+ return 0;
+
+err_pm:
+ pm_runtime_put(&pdev->dev);
+err_pm_disable:
+ pm_runtime_disable(&pdev->dev);
+ reset_control_assert(chip->rstc);
+
+ return ret;
+}
+
+static int rzg2l_poeg_remove(struct platform_device *pdev)
+{
+ struct rzg2l_poeg_chip *chip = platform_get_drvdata(pdev);
+
+ sysfs_remove_group(&pdev->dev.kobj, &poeg_groups);
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ reset_control_assert(chip->rstc);
+
+ return 0;
+}
+
+static struct platform_driver rzg2l_poeg_driver = {
+ .driver = {
+ .name = "rzg2l-poeg",
+ .of_match_table = of_match_ptr(rzg2l_poeg_of_table),
+ },
+ .probe = rzg2l_poeg_probe,
+ .remove = rzg2l_poeg_remove,
+};
+module_platform_driver(rzg2l_poeg_driver);
+
+MODULE_AUTHOR("Biju Das <biju.das.jz@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Renesas RZ/G2L POEG Driver");
+MODULE_LICENSE("GPL");
--
2.25.1
