net: dsa: ksz: Add Microchip KSZ8795 DSA driver

Add Microchip KSZ8795 DSA driver.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Tristram Ha <Tristram.Ha@microchip.com>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/microchip/ksz8795_spi.c

@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Microchip KSZ8795 series register access through SPI
+ *
+ * Copyright (C) 2017 Microchip Technology Inc.
+ *	Tristram Ha <Tristram.Ha@microchip.com>
+ */
+
+#include <asm/unaligned.h>
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "ksz_priv.h"
+#include "ksz_common.h"
+
+#define SPI_ADDR_SHIFT			12
+#define SPI_ADDR_ALIGN			3
+#define SPI_TURNAROUND_SHIFT		1
+
+KSZ_REGMAP_TABLE(ksz8795, 16, SPI_ADDR_SHIFT,
+		 SPI_TURNAROUND_SHIFT, SPI_ADDR_ALIGN);
+
+static int ksz8795_spi_probe(struct spi_device *spi)
+{
+	struct ksz_device *dev;
+	int i, ret;
+
+	dev = ksz_switch_alloc(&spi->dev, spi);
+	if (!dev)
+		return -ENOMEM;
+
+	for (i = 0; i < ARRAY_SIZE(ksz8795_regmap_config); i++) {
+		dev->regmap[i] = devm_regmap_init_spi(spi,
+						      &ksz8795_regmap_config
+						      [i]);
+		if (IS_ERR(dev->regmap[i])) {
+			ret = PTR_ERR(dev->regmap[i]);
+			dev_err(&spi->dev,
+				"Failed to initialize regmap%i: %d\n",
+				ksz8795_regmap_config[i].val_bits, ret);
+			return ret;
+		}
+	}
+
+	if (spi->dev.platform_data)
+		dev->pdata = spi->dev.platform_data;
+
+	ret = ksz8795_switch_register(dev);
+
+	/* Main DSA driver may not be started yet. */
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, dev);
+
+	return 0;
+}
+
+static int ksz8795_spi_remove(struct spi_device *spi)
+{
+	struct ksz_device *dev = spi_get_drvdata(spi);
+
+	if (dev)
+		ksz_switch_remove(dev);
+
+	return 0;
+}
+
+static void ksz8795_spi_shutdown(struct spi_device *spi)
+{
+	struct ksz_device *dev = spi_get_drvdata(spi);
+
+	if (dev && dev->dev_ops->shutdown)
+		dev->dev_ops->shutdown(dev);
+}
+
+static const struct of_device_id ksz8795_dt_ids[] = {
+	{ .compatible = "microchip,ksz8765" },
+	{ .compatible = "microchip,ksz8794" },
+	{ .compatible = "microchip,ksz8795" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ksz8795_dt_ids);
+
+static struct spi_driver ksz8795_spi_driver = {
+	.driver = {
+		.name	= "ksz8795-switch",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(ksz8795_dt_ids),
+	},
+	.probe	= ksz8795_spi_probe,
+	.remove	= ksz8795_spi_remove,
+	.shutdown = ksz8795_spi_shutdown,
+};
+
+module_spi_driver(ksz8795_spi_driver);
+
+MODULE_AUTHOR("Tristram Ha <Tristram.Ha@microchip.com>");
+MODULE_DESCRIPTION("Microchip KSZ8795 Series Switch SPI Driver");
+MODULE_LICENSE("GPL");