Add support for Generic Mux controls, when Mdio mux node is a consumer
of mux produced by some other device.
Signed-off-by: Pankaj Bansal <pankaj.ban...@nxp.com>
---
Notes:
V2:
- Moved the changes from mdio-mux module to new module mdio-mux-multiplexer
- defined new CONFIG
- using new compatible "mdio-mux-multiplexer"
diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index 3d187cd50eb0..7f66af446ec7 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -87,6 +87,18 @@ config MDIO_BUS_MUX_MMIOREG
Currently, only 8/16/32 bits registers are supported.
+config MDIO_BUS_MUX_MULTIPLEXER
+ tristate "MDIO bus multiplexer using kernel multiplexer subsystem"
+ depends on OF
+ select MULTIPLEXER
+ select MDIO_BUS_MUX
+ help
+ This module provides a driver for MDIO bus multiplexer
+ that is controlled via the kernel multiplexer subsystem. The
+ bus multiplexer connects one of several child MDIO busses to
+ a parent bus. Child bus selection is under the control of
+ the kernel multiplexer subsystem.
+
config MDIO_CAVIUM
tristate
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 5805c0b7d60e..766106237a90 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_MDIO_BUS_MUX) += mdio-mux.o
obj-$(CONFIG_MDIO_BUS_MUX_BCM_IPROC) += mdio-mux-bcm-iproc.o
obj-$(CONFIG_MDIO_BUS_MUX_GPIO) += mdio-mux-gpio.o
obj-$(CONFIG_MDIO_BUS_MUX_MMIOREG) += mdio-mux-mmioreg.o
+obj-$(CONFIG_MDIO_BUS_MUX_MULTIPLEXER) += mdio-mux-multiplexer.o
obj-$(CONFIG_MDIO_CAVIUM) += mdio-cavium.o
obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o
obj-$(CONFIG_MDIO_HISI_FEMAC) += mdio-hisi-femac.o
diff --git a/drivers/net/phy/mdio-mux-multiplexer.c
b/drivers/net/phy/mdio-mux-multiplexer.c
new file mode 100644
index 000000000000..22adbbb93aa6
--- /dev/null
+++ b/drivers/net/phy/mdio-mux-multiplexer.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* MDIO bus multiplexer using kernel multiplexer subsystem
+ *
+ * Copyright 2019 NXP
+ */
+
+#include <linux/platform_device.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+
+struct mdio_mux_multiplexer_state {
+ struct mux_control *muxc;
+ void *mux_handle;
+};
+
+/**
+ * mdio_mux_multiplexer_switch_fn - This function is called by the mdio-mux
+ * layer when it thinks the mdio bus
+ * multiplexer needs to switch.
+ * @current_child: current value of the mux register.
+ * @desired_child: value of the 'reg' property of the target child MDIO node.
+ * @data: Private data used by this switch_fn passed to mdio_mux_init function
+ * via mdio_mux_init(.., .., .., .., data, ..).
+ *
+ * The first time this function is called, current_child == -1.
+ * If current_child == desired_child, then the mux is already set to the
+ * correct bus.
+ */
+static int mdio_mux_multiplexer_switch_fn(int current_child, int desired_child,
+ void *data)
+{
+ struct platform_device *pdev;
+ struct mdio_mux_multiplexer_state *s;
+ int ret = 0;
+
+ pdev = (struct platform_device *)data;
+ s = (struct mdio_mux_multiplexer_state *)platform_get_drvdata(pdev);
+ if (current_child ^ desired_child) {
+ if (current_child != -1)
+ ret = mux_control_deselect(s->muxc);
+ if (ret)
+ return ret;
+
+ ret = mux_control_select(s->muxc, desired_child);
+ if (!ret)
+ dev_dbg(&pdev->dev, "%s %d -> %d\n", __func__,
+ current_child, desired_child);
+ }
+
+ return ret;
+}
+
+static int mdio_mux_multiplexer_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mdio_mux_multiplexer_state *s;
+ int ret = 0;
+
+ s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ s->muxc = devm_mux_control_get(dev, NULL);
+ if (IS_ERR(s->muxc)) {
+ ret = PTR_ERR(s->muxc);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "Failed to get mux: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, s);
+
+ ret = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
+ mdio_mux_multiplexer_switch_fn, &s->mux_handle,
+ pdev, NULL);
+
+ return ret;
+}
+
+static int mdio_mux_multiplexer_remove(struct platform_device *pdev)
+{
+ struct mdio_mux_multiplexer_state *s = platform_get_drvdata(pdev);
+
+ mdio_mux_uninit(s->mux_handle);
+
+ return 0;
+}
+
+static const struct of_device_id mdio_mux_multiplexer_match[] = {
+ { .compatible = "mdio-mux-multiplexer", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_multiplexer_match);
+
+static struct platform_driver mdio_mux_multiplexer_driver = {
+ .driver = {
+ .name = "mdio-mux-multiplexer",
+ .of_match_table = mdio_mux_multiplexer_match,
+ },
+ .probe = mdio_mux_multiplexer_probe,
+ .remove = mdio_mux_multiplexer_remove,
+};
+
+module_platform_driver(mdio_mux_multiplexer_driver);
+
+MODULE_DESCRIPTION("MDIO bus multiplexer using kernel multiplexer subsystem");
+MODULE_AUTHOR("Pankaj Bansal");
+MODULE_LICENSE("GPL");
--
2.17.1
