[PATCH v3 4/6] reset: Add Delta TN48M CPLD reset controller

From: Robert Marko
Date: Mon May 31 2021 - 08:52:22 EST


Delta TN48M CPLD exposes resets for the following:
* 88F7040 SoC
* 88F6820 SoC
* 98DX3265 switch MAC-s
* 88E1680 PHY-s
* 88E1512 PHY
* PoE PSE controller

Signed-off-by: Robert Marko <robert.marko@xxxxxxxxxx>
---
drivers/reset/Kconfig | 9 +++
drivers/reset/Makefile | 1 +
drivers/reset/reset-tn48m.c | 128 ++++++++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)
create mode 100644 drivers/reset/reset-tn48m.c

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 4171c6f76385..e3ff4b020c96 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -64,6 +64,15 @@ config RESET_BRCMSTB_RESCAL
This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1 on
BCM7216.

+config RESET_TN48M_CPLD
+ tristate "Delta Networks TN48M switch CPLD reset controller"
+ depends on MFD_TN48M_CPLD
+ help
+ This enables the reset controller driver for the Delta TN48M CPLD.
+ It provides reset signals for Armada 7040 and 385 SoC-s, Alleycat 3X
+ switch MAC-s, Alaska OOB ethernet PHY, Quad Alaska ethernet PHY-s and
+ Microchip PD69200 PoE PSE controller.
+
config RESET_HSDK
bool "Synopsys HSDK Reset Driver"
depends on HAS_IOMEM
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 65a118a91b27..6d6945638b76 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
+obj-$(CONFIG_RESET_TN48M_CPLD) += reset-tn48m.o
obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o
diff --git a/drivers/reset/reset-tn48m.c b/drivers/reset/reset-tn48m.c
new file mode 100644
index 000000000000..960ee5f4eb40
--- /dev/null
+++ b/drivers/reset/reset-tn48m.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Delta TN48M CPLD reset driver
+ *
+ * Copyright 2021 Sartura Ltd
+ *
+ * Author: Robert Marko <robert.marko@xxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#include <dt-bindings/reset/delta,tn48m-reset.h>
+
+#define TN48M_RESET_REG 0x10
+
+struct tn48_reset_map {
+ u8 bit;
+};
+
+struct tn48_reset_data {
+ struct reset_controller_dev rcdev;
+ struct regmap *regmap;
+};
+
+static const struct tn48_reset_map tn48m_resets[] = {
+ [CPU_88F7040_RESET] = {0},
+ [CPU_88F6820_RESET] = {1},
+ [MAC_98DX3265_RESET] = {2},
+ [PHY_88E1680_RESET] = {4},
+ [PHY_88E1512_RESET] = {6},
+ [POE_RESET] = {7},
+};
+
+static inline struct tn48_reset_data *to_tn48_reset_data(
+ struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct tn48_reset_data, rcdev);
+}
+
+static int tn48m_control_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct tn48_reset_data *data = to_tn48_reset_data(rcdev);
+
+ return regmap_update_bits(data->regmap, TN48M_RESET_REG,
+ BIT(tn48m_resets[id].bit), 0);
+}
+
+static int tn48m_control_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return tn48m_control_assert(rcdev, id);
+}
+
+static int tn48m_control_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct tn48_reset_data *data = to_tn48_reset_data(rcdev);
+ unsigned int regval;
+ int ret;
+
+ ret = regmap_read(data->regmap, TN48M_RESET_REG, &regval);
+ if (ret < 0)
+ return ret;
+
+ if (BIT(tn48m_resets[id].bit) & regval)
+ return 0;
+ else
+ return 1;
+}
+
+static const struct reset_control_ops tn48_reset_ops = {
+ .reset = tn48m_control_reset,
+ .assert = tn48m_control_assert,
+ .status = tn48m_control_status,
+};
+
+static int tn48m_reset_probe(struct platform_device *pdev)
+{
+ struct tn48_reset_data *data;
+ struct regmap *regmap;
+
+ if (!pdev->dev.parent)
+ return -ENODEV;
+
+ regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!regmap)
+ return -ENODEV;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->regmap = regmap;
+
+ data->rcdev.owner = THIS_MODULE;
+ data->rcdev.ops = &tn48_reset_ops;
+ data->rcdev.nr_resets = ARRAY_SIZE(tn48m_resets);
+ data->rcdev.of_node = pdev->dev.of_node;
+
+ return devm_reset_controller_register(&pdev->dev, &data->rcdev);
+}
+
+static const struct of_device_id tn48m_reset_of_match[] = {
+ { .compatible = "delta,tn48m-reset", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, tn48m_reset_of_match);
+
+static struct platform_driver tn48m_reset_driver = {
+ .driver = {
+ .name = "delta-tn48m-reset",
+ .of_match_table = tn48m_reset_of_match,
+ },
+ .probe = tn48m_reset_probe,
+};
+module_platform_driver(tn48m_reset_driver);
+
+MODULE_AUTHOR("Robert Marko <robert.marko@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Delta TN48M CPLD reset driver");
+MODULE_LICENSE("GPL");
--
2.31.1