net: dsa: microchip: break KSZ9477 DSA driver into two files

Break KSZ9477 DSA driver into two files in preparation to add more KSZ
switch drivers.
Add common functions in ksz_common.h so that other KSZ switch drivers
can access code in ksz_common.c.
Add ksz_spi.h for common functions used by KSZ switch SPI drivers.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Reviewed-by: Woojung Huh <Woojung.Huh@microchip.com>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 57 insertions, 86 deletions

diff --git a/drivers/net/dsa/microchip/ksz9477_spi.c b/drivers/net/dsa/microchip/ksz9477_spi.c
index dc70f486719c..d757ba151cb1 100644
--- a/drivers/net/dsa/microchip/ksz9477_spi.c
+++ b/drivers/net/dsa/microchip/ksz9477_spi.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Microchip KSZ series register access through SPI
+ * Microchip KSZ9477 series register access through SPI
  *
  * Copyright (C) 2017-2018 Microchip Technology Inc.
  */
@@ -13,6 +13,7 @@
 #include <linux/spi/spi.h>
 
 #include "ksz_priv.h"
+#include "ksz_spi.h"
 
 /* SPI frame opcodes */
 #define KS_SPIOP_RD			3
@@ -22,8 +23,11 @@
 #define SPI_ADDR_MASK			(BIT(SPI_ADDR_SHIFT) - 1)
 #define SPI_TURNAROUND_SHIFT		5
 
-static int ksz_spi_read_reg(struct spi_device *spi, u32 reg, u8 *val,
-			    unsigned int len)
+/* Enough to read all switch port registers. */
+#define SPI_TX_BUF_LEN			0x100
+
+static int ksz9477_spi_read_reg(struct spi_device *spi, u32 reg, u8 *val,
+				unsigned int len)
 {
 	u32 txbuf;
 	int ret;
@@ -37,27 +41,36 @@ static int ksz_spi_read_reg(struct spi_device *spi, u32 reg, u8 *val,
 	return ret;
 }
 
-static int ksz_spi_read(struct ksz_device *dev, u32 reg, u8 *data,
-			unsigned int len)
+static int ksz9477_spi_write_reg(struct spi_device *spi, u32 reg, u8 *val,
+				 unsigned int len)
 {
-	struct spi_device *spi = dev->priv;
+	u32 *txbuf = (u32 *)val;
 
-	return ksz_spi_read_reg(spi, reg, data, len);
+	*txbuf = reg & SPI_ADDR_MASK;
+	*txbuf |= (KS_SPIOP_WR << SPI_ADDR_SHIFT);
+	*txbuf <<= SPI_TURNAROUND_SHIFT;
+	*txbuf = cpu_to_be32(*txbuf);
+
+	return spi_write(spi, txbuf, 4 + len);
 }
 
-static int ksz_spi_read8(struct ksz_device *dev, u32 reg, u8 *val)
+static int ksz_spi_read(struct ksz_device *dev, u32 reg, u8 *data,
+			unsigned int len)
 {
-	return ksz_spi_read(dev, reg, val, 1);
+	struct spi_device *spi = dev->priv;
+
+	return ksz9477_spi_read_reg(spi, reg, data, len);
 }
 
-static int ksz_spi_read16(struct ksz_device *dev, u32 reg, u16 *val)
+static int ksz_spi_write(struct ksz_device *dev, u32 reg, void *data,
+			 unsigned int len)
 {
-	int ret = ksz_spi_read(dev, reg, (u8 *)val, 2);
-
-	if (!ret)
-		*val = be16_to_cpu(*val);
+	struct spi_device *spi = dev->priv;
 
-	return ret;
+	if (len > SPI_TX_BUF_LEN)
+		len = SPI_TX_BUF_LEN;
+	memcpy(&dev->txbuf[4], data, len);
+	return ksz9477_spi_write_reg(spi, reg, dev->txbuf, len);
 }
 
 static int ksz_spi_read24(struct ksz_device *dev, u32 reg, u32 *val)
@@ -75,72 +88,15 @@ static int ksz_spi_read24(struct ksz_device *dev, u32 reg, u32 *val)
 	return ret;
 }
 
-static int ksz_spi_read32(struct ksz_device *dev, u32 reg, u32 *val)
-{
-	int ret = ksz_spi_read(dev, reg, (u8 *)val, 4);
-
-	if (!ret)
-		*val = be32_to_cpu(*val);
-
-	return ret;
-}
-
-static int ksz_spi_write_reg(struct spi_device *spi, u32 reg, u8 *val,
-			     unsigned int len)
-{
-	u32 txbuf;
-	u8 data[12];
-	int i;
-
-	txbuf = reg & SPI_ADDR_MASK;
-	txbuf |= (KS_SPIOP_WR << SPI_ADDR_SHIFT);
-	txbuf <<= SPI_TURNAROUND_SHIFT;
-	txbuf = cpu_to_be32(txbuf);
-
-	data[0] = txbuf & 0xFF;
-	data[1] = (txbuf & 0xFF00) >> 8;
-	data[2] = (txbuf & 0xFF0000) >> 16;
-	data[3] = (txbuf & 0xFF000000) >> 24;
-	for (i = 0; i < len; i++)
-		data[i + 4] = val[i];
-
-	return spi_write(spi, &data, 4 + len);
-}
-
-static int ksz_spi_write8(struct ksz_device *dev, u32 reg, u8 value)
-{
-	struct spi_device *spi = dev->priv;
-
-	return ksz_spi_write_reg(spi, reg, &value, 1);
-}
-
-static int ksz_spi_write16(struct ksz_device *dev, u32 reg, u16 value)
-{
-	struct spi_device *spi = dev->priv;
-
-	value = cpu_to_be16(value);
-	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 2);
-}
-
 static int ksz_spi_write24(struct ksz_device *dev, u32 reg, u32 value)
 {
-	struct spi_device *spi = dev->priv;
-
 	/* make it to big endian 24bit from MSB */
 	value <<= 8;
 	value = cpu_to_be32(value);
-	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 3);
+	return ksz_spi_write(dev, reg, &value, 3);
 }
 
-static int ksz_spi_write32(struct ksz_device *dev, u32 reg, u32 value)
-{
-	struct spi_device *spi = dev->priv;
-
-	value = cpu_to_be32(value);
-	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 4);
-}
-
-static const struct ksz_io_ops ksz_spi_ops = {
+static const struct ksz_io_ops ksz9477_spi_ops = {
 	.read8 = ksz_spi_read8,
 	.read16 = ksz_spi_read16,
 	.read24 = ksz_spi_read24,
@@ -149,21 +105,27 @@ static const struct ksz_io_ops ksz_spi_ops = {
 	.write16 = ksz_spi_write16,
 	.write24 = ksz_spi_write24,
 	.write32 = ksz_spi_write32,
+	.get = ksz_spi_get,
+	.set = ksz_spi_set,
 };
 
-static int ksz_spi_probe(struct spi_device *spi)
+static int ksz9477_spi_probe(struct spi_device *spi)
 {
 	struct ksz_device *dev;
 	int ret;
 
-	dev = ksz_switch_alloc(&spi->dev, &ksz_spi_ops, spi);
+	dev = ksz_switch_alloc(&spi->dev, &ksz9477_spi_ops, spi);
 	if (!dev)
 		return -ENOMEM;
 
 	if (spi->dev.platform_data)
 		dev->pdata = spi->dev.platform_data;
 
-	ret = ksz_switch_register(dev);
+	dev->txbuf = devm_kzalloc(dev->dev, 4 + SPI_TX_BUF_LEN, GFP_KERNEL);
+
+	ret = ksz9477_switch_register(dev);
+
+	/* Main DSA driver may not be started yet. */
 	if (ret)
 		return ret;
 
@@ -172,7 +134,7 @@ static int ksz_spi_probe(struct spi_device *spi)
 	return 0;
 }
 
-static int ksz_spi_remove(struct spi_device *spi)
+static int ksz9477_spi_remove(struct spi_device *spi)
 {
 	struct ksz_device *dev = spi_get_drvdata(spi);
 
@@ -182,25 +144,34 @@ static int ksz_spi_remove(struct spi_device *spi)
 	return 0;
 }
 
-static const struct of_device_id ksz_dt_ids[] = {
+static void ksz9477_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 ksz9477_dt_ids[] = {
 	{ .compatible = "microchip,ksz9477" },
 	{ .compatible = "microchip,ksz9897" },
 	{},
 };
-MODULE_DEVICE_TABLE(of, ksz_dt_ids);
+MODULE_DEVICE_TABLE(of, ksz9477_dt_ids);
 
-static struct spi_driver ksz_spi_driver = {
+static struct spi_driver ksz9477_spi_driver = {
 	.driver = {
 		.name	= "ksz9477-switch",
 		.owner	= THIS_MODULE,
-		.of_match_table = of_match_ptr(ksz_dt_ids),
+		.of_match_table = of_match_ptr(ksz9477_dt_ids),
 	},
-	.probe	= ksz_spi_probe,
-	.remove	= ksz_spi_remove,
+	.probe	= ksz9477_spi_probe,
+	.remove	= ksz9477_spi_remove,
+	.shutdown = ksz9477_spi_shutdown,
 };
 
-module_spi_driver(ksz_spi_driver);
+module_spi_driver(ksz9477_spi_driver);
 
 MODULE_AUTHOR("Woojung Huh <Woojung.Huh@microchip.com>");
-MODULE_DESCRIPTION("Microchip KSZ Series Switch SPI access Driver");
+MODULE_DESCRIPTION("Microchip KSZ9477 Series Switch SPI access Driver");
 MODULE_LICENSE("GPL");