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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-10-20 00:10:27 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-10-20 00:10:27 -0300
commitd0b2f91bede3bd5e3d24dd6803e56eee959c1797 (patch)
tree7fee4ab0509879c373c4f2cbd5b8a5be5b4041ee /drivers/net/dsa/b53/b53_spi.c
parente914f8eb445e8f74b00303c19c2ffceaedd16a05 (diff)
Linux-libre 4.8.2-gnupck-4.8.2-gnu
Diffstat (limited to 'drivers/net/dsa/b53/b53_spi.c')
-rw-r--r--drivers/net/dsa/b53/b53_spi.c331
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");