Linux-libre 4.8.2-gnupck-4.8.2-gnu

1 files changed, 331 insertions, 0 deletions

diff --git a/drivers/net/dsa/b53/b53_spi.c b/drivers/net/dsa/b53/b53_spi.c
new file mode 100644
index 000000000..2bda0b5f1
--- /dev/null
+++ b/drivers/net/dsa/b53/b53_spi.c
@@ -0,0 +1,331 @@
+/*
+ * B53 register access through SPI
+ *
+ * Copyright (C) 2011-2013 Jonas Gorski <jogo@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <asm/unaligned.h>
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/platform_data/b53.h>
+
+#include "b53_priv.h"
+
+#define B53_SPI_DATA		0xf0
+
+#define B53_SPI_STATUS		0xfe
+#define B53_SPI_CMD_SPIF	BIT(7)
+#define B53_SPI_CMD_RACK	BIT(5)
+
+#define B53_SPI_CMD_READ	0x00
+#define B53_SPI_CMD_WRITE	0x01
+#define B53_SPI_CMD_NORMAL	0x60
+#define B53_SPI_CMD_FAST	0x10
+
+#define B53_SPI_PAGE_SELECT	0xff
+
+static inline int b53_spi_read_reg(struct spi_device *spi, u8 reg, u8 *val,
+				   unsigned int len)
+{
+	u8 txbuf[2];
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_READ;
+	txbuf[1] = reg;
+
+	return spi_write_then_read(spi, txbuf, 2, val, len);
+}
+
+static inline int b53_spi_clear_status(struct spi_device *spi)
+{
+	unsigned int i;
+	u8 rxbuf;
+	int ret;
+
+	for (i = 0; i < 10; i++) {
+		ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
+		if (ret)
+			return ret;
+
+		if (!(rxbuf & B53_SPI_CMD_SPIF))
+			break;
+
+		mdelay(1);
+	}
+
+	if (i == 10)
+		return -EIO;
+
+	return 0;
+}
+
+static inline int b53_spi_set_page(struct spi_device *spi, u8 page)
+{
+	u8 txbuf[3];
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = B53_SPI_PAGE_SELECT;
+	txbuf[2] = page;
+
+	return spi_write(spi, txbuf, sizeof(txbuf));
+}
+
+static inline int b53_prepare_reg_access(struct spi_device *spi, u8 page)
+{
+	int ret = b53_spi_clear_status(spi);
+
+	if (ret)
+		return ret;
+
+	return b53_spi_set_page(spi, page);
+}
+
+static int b53_spi_prepare_reg_read(struct spi_device *spi, u8 reg)
+{
+	u8 rxbuf;
+	int retry_count;
+	int ret;
+
+	ret = b53_spi_read_reg(spi, reg, &rxbuf, 1);
+	if (ret)
+		return ret;
+
+	for (retry_count = 0; retry_count < 10; retry_count++) {
+		ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
+		if (ret)
+			return ret;
+
+		if (rxbuf & B53_SPI_CMD_RACK)
+			break;
+
+		mdelay(1);
+	}
+
+	if (retry_count == 10)
+		return -EIO;
+
+	return 0;
+}
+
+static int b53_spi_read(struct b53_device *dev, u8 page, u8 reg, u8 *data,
+			unsigned int len)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	ret = b53_spi_prepare_reg_read(spi, reg);
+	if (ret)
+		return ret;
+
+	return b53_spi_read_reg(spi, B53_SPI_DATA, data, len);
+}
+
+static int b53_spi_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
+{
+	return b53_spi_read(dev, page, reg, val, 1);
+}
+
+static int b53_spi_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
+{
+	int ret = b53_spi_read(dev, page, reg, (u8 *)val, 2);
+
+	if (!ret)
+		*val = le16_to_cpu(*val);
+
+	return ret;
+}
+
+static int b53_spi_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
+{
+	int ret = b53_spi_read(dev, page, reg, (u8 *)val, 4);
+
+	if (!ret)
+		*val = le32_to_cpu(*val);
+
+	return ret;
+}
+
+static int b53_spi_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
+{
+	int ret;
+
+	*val = 0;
+	ret = b53_spi_read(dev, page, reg, (u8 *)val, 6);
+	if (!ret)
+		*val = le64_to_cpu(*val);
+
+	return ret;
+}
+
+static int b53_spi_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
+{
+	int ret = b53_spi_read(dev, page, reg, (u8 *)val, 8);
+
+	if (!ret)
+		*val = le64_to_cpu(*val);
+
+	return ret;
+}
+
+static int b53_spi_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+	u8 txbuf[3];
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = reg;
+	txbuf[2] = value;
+
+	return spi_write(spi, txbuf, sizeof(txbuf));
+}
+
+static int b53_spi_write16(struct b53_device *dev, u8 page, u8 reg, u16 value)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+	u8 txbuf[4];
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = reg;
+	put_unaligned_le16(value, &txbuf[2]);
+
+	return spi_write(spi, txbuf, sizeof(txbuf));
+}
+
+static int b53_spi_write32(struct b53_device *dev, u8 page, u8 reg, u32 value)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+	u8 txbuf[6];
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = reg;
+	put_unaligned_le32(value, &txbuf[2]);
+
+	return spi_write(spi, txbuf, sizeof(txbuf));
+}
+
+static int b53_spi_write48(struct b53_device *dev, u8 page, u8 reg, u64 value)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+	u8 txbuf[10];
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = reg;
+	put_unaligned_le64(value, &txbuf[2]);
+
+	return spi_write(spi, txbuf, sizeof(txbuf) - 2);
+}
+
+static int b53_spi_write64(struct b53_device *dev, u8 page, u8 reg, u64 value)
+{
+	struct spi_device *spi = dev->priv;
+	int ret;
+	u8 txbuf[10];
+
+	ret = b53_prepare_reg_access(spi, page);
+	if (ret)
+		return ret;
+
+	txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
+	txbuf[1] = reg;
+	put_unaligned_le64(value, &txbuf[2]);
+
+	return spi_write(spi, txbuf, sizeof(txbuf));
+}
+
+static struct b53_io_ops b53_spi_ops = {
+	.read8 = b53_spi_read8,
+	.read16 = b53_spi_read16,
+	.read32 = b53_spi_read32,
+	.read48 = b53_spi_read48,
+	.read64 = b53_spi_read64,
+	.write8 = b53_spi_write8,
+	.write16 = b53_spi_write16,
+	.write32 = b53_spi_write32,
+	.write48 = b53_spi_write48,
+	.write64 = b53_spi_write64,
+};
+
+static int b53_spi_probe(struct spi_device *spi)
+{
+	struct b53_device *dev;
+	int ret;
+
+	dev = b53_switch_alloc(&spi->dev, &b53_spi_ops, spi);
+	if (!dev)
+		return -ENOMEM;
+
+	if (spi->dev.platform_data)
+		dev->pdata = spi->dev.platform_data;
+
+	ret = b53_switch_register(dev);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, dev);
+
+	return 0;
+}
+
+static int b53_spi_remove(struct spi_device *spi)
+{
+	struct b53_device *dev = spi_get_drvdata(spi);
+
+	if (dev)
+		b53_switch_remove(dev);
+
+	return 0;
+}
+
+static struct spi_driver b53_spi_driver = {
+	.driver = {
+		.name	= "b53-switch",
+		.bus	= &spi_bus_type,
+		.owner	= THIS_MODULE,
+	},
+	.probe	= b53_spi_probe,
+	.remove	= b53_spi_remove,
+};
+
+module_spi_driver(b53_spi_driver);
+
+MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
+MODULE_DESCRIPTION("B53 SPI access driver");
+MODULE_LICENSE("Dual BSD/GPL");