net: dsa: LAN9303: add I2C managed mode support

In this mode the switch device and the internal phys will be managed via
I2C interface. The MDIO interface is still supported, but for the
(emulated) CPU port only.

Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
CC: devicetree@vger.kernel.org
CC: robh+dt@kernel.org
CC: mark.rutland@arm.com
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 113 insertions, 0 deletions

diff --git a/drivers/net/dsa/lan9303_i2c.c b/drivers/net/dsa/lan9303_i2c.c
new file mode 100644
index 000000000000..ab3ce0da5071
--- /dev/null
+++ b/drivers/net/dsa/lan9303_i2c.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2017 Pengutronix, Juergen Borleis <kernel@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/of.h>
+
+#include "lan9303.h"
+
+struct lan9303_i2c {
+	struct i2c_client *device;
+	struct lan9303 chip;
+};
+
+static const struct regmap_config lan9303_i2c_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 1,
+	.can_multi_write = true,
+	.max_register = 0x0ff, /* address bits 0..1 are not used */
+	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
+
+	.volatile_table = &lan9303_register_set,
+	.wr_table = &lan9303_register_set,
+	.rd_table = &lan9303_register_set,
+
+	.cache_type = REGCACHE_NONE,
+};
+
+static int lan9303_i2c_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct lan9303_i2c *sw_dev;
+	int ret;
+
+	sw_dev = devm_kzalloc(&client->dev, sizeof(struct lan9303_i2c),
+			      GFP_KERNEL);
+	if (!sw_dev)
+		return -ENOMEM;
+
+	sw_dev->chip.regmap = devm_regmap_init_i2c(client,
+						&lan9303_i2c_regmap_config);
+	if (IS_ERR(sw_dev->chip.regmap)) {
+		ret = PTR_ERR(sw_dev->chip.regmap);
+		dev_err(&client->dev, "Failed to allocate register map: %d\n",
+			ret);
+		return ret;
+	}
+
+	/* link forward and backward */
+	sw_dev->device = client;
+	i2c_set_clientdata(client, sw_dev);
+	sw_dev->chip.dev = &client->dev;
+
+	ret = lan9303_probe(&sw_dev->chip, client->dev.of_node);
+	if (ret != 0)
+		return ret;
+
+	dev_info(&client->dev, "LAN9303 I2C driver loaded successfully\n");
+
+	return 0;
+}
+
+static int lan9303_i2c_remove(struct i2c_client *client)
+{
+	struct lan9303_i2c *sw_dev;
+
+	sw_dev = i2c_get_clientdata(client);
+	if (!sw_dev)
+		return -ENODEV;
+
+	return lan9303_remove(&sw_dev->chip);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static const struct i2c_device_id lan9303_i2c_id[] = {
+	{ "lan9303", 0 },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, lan9303_i2c_id);
+
+static const struct of_device_id lan9303_i2c_of_match[] = {
+	{ .compatible = "smsc,lan9303-i2c", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, lan9303_i2c_of_match);
+
+static struct i2c_driver lan9303_i2c_driver = {
+	.driver = {
+		.name = "LAN9303_I2C",
+		.of_match_table = of_match_ptr(lan9303_i2c_of_match),
+	},
+	.probe = lan9303_i2c_probe,
+	.remove = lan9303_i2c_remove,
+	.id_table = lan9303_i2c_id,
+};
+module_i2c_driver(lan9303_i2c_driver);
+
+MODULE_AUTHOR("Juergen Borleis <kernel@pengutronix.de>");
+MODULE_DESCRIPTION("Driver for SMSC/Microchip LAN9303 three port ethernet switch in I2C managed mode");
+MODULE_LICENSE("GPL v2");