1 files changed, 448 insertions, 0 deletions
diff --git a/target/linux/cns3xxx/files/drivers/spi/spi-cns3xxx.c b/target/linux/cns3xxx/files/drivers/spi/spi-cns3xxx.c
new file mode 100644
index 0000000..6301986
--- /dev/null
+++ b/target/linux/cns3xxx/files/drivers/spi/spi-cns3xxx.c
@@ -0,0 +1,448 @@
+/*******************************************************************************
+ *
+ *  CNS3XXX SPI controller driver (master mode only)
+ *
+ *  Copyright (c) 2008 Cavium Networks
+ *  Copyright 2011 Gateworks Corporation
+ *		   Chris Lang <clang@gateworks.com>
+ *
+ *  This file 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 file is distributed in the hope that it will be useful,
+ *  but AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
+ *  NONINFRINGEMENT.  See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this file; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA or
+ *  visit http://www.gnu.org/licenses/.
+ *
+ *  This file may also be available under a different license from Cavium.
+ *  Contact Cavium Networks for more information
+ *
+ ******************************************************************************/
+
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/mtd/partitions.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+
+#include <asm/io.h>
+#include <asm/memory.h>
+#include <asm/dma.h>
+#include <asm/delay.h>
+#include <linux/module.h>
+
+/*
+ * define access macros
+ */
+#define SPI_MEM_MAP_VALUE(reg_offset)		(*((u32 volatile *)(hw->base + reg_offset)))
+
+#define SPI_CONFIGURATION_REG			SPI_MEM_MAP_VALUE(0x00)
+#define SPI_SERVICE_STATUS_REG			SPI_MEM_MAP_VALUE(0x04)
+#define SPI_BIT_RATE_CONTROL_REG		SPI_MEM_MAP_VALUE(0x08)
+#define SPI_TRANSMIT_CONTROL_REG		SPI_MEM_MAP_VALUE(0x0C)
+#define SPI_TRANSMIT_BUFFER_REG			SPI_MEM_MAP_VALUE(0x10)
+#define SPI_RECEIVE_CONTROL_REG			SPI_MEM_MAP_VALUE(0x14)
+#define SPI_RECEIVE_BUFFER_REG			SPI_MEM_MAP_VALUE(0x18)
+#define SPI_FIFO_TRANSMIT_CONFIG_REG		SPI_MEM_MAP_VALUE(0x1C)
+#define SPI_FIFO_TRANSMIT_CONTROL_REG		SPI_MEM_MAP_VALUE(0x20)
+#define SPI_FIFO_RECEIVE_CONFIG_REG		SPI_MEM_MAP_VALUE(0x24)
+#define SPI_INTERRUPT_STATUS_REG		SPI_MEM_MAP_VALUE(0x28)
+#define SPI_INTERRUPT_ENABLE_REG		SPI_MEM_MAP_VALUE(0x2C)
+
+#define SPI_TRANSMIT_BUFFER_REG_ADDR		(CNS3XXX_SSP_BASE +0x10)
+#define SPI_RECEIVE_BUFFER_REG_ADDR		(CNS3XXX_SSP_BASE +0x18)
+
+/* Structure for SPI controller of CNS3XXX SOCs */
+struct cns3xxx_spi {
+	/* bitbang has to be first */
+	struct spi_bitbang bitbang;
+	struct completion done;
+	wait_queue_head_t wait;
+
+	int len;
+	int count;
+	int last_in_message_list;
+
+	/* data buffers */
+	const unsigned char *tx;
+	unsigned char *rx;
+
+	void __iomem *base;
+	struct spi_master *master;
+	struct platform_device *pdev;
+	struct device *dev;
+};
+
+static inline u8 cns3xxx_spi_bus_idle(struct cns3xxx_spi *hw)
+{
+	return ((SPI_SERVICE_STATUS_REG & 0x1) ? 0 : 1);
+}
+
+static inline u8 cns3xxx_spi_tx_buffer_empty(struct cns3xxx_spi *hw)
+{
+	return ((SPI_INTERRUPT_STATUS_REG & (0x1 << 3)) ? 1 : 0);
+}
+
+static inline u8 cns3xxx_spi_rx_buffer_full(struct cns3xxx_spi *hw)
+{
+	return ((SPI_INTERRUPT_STATUS_REG & (0x1 << 2)) ? 1 : 0);
+}
+
+u8 cns3xxx_spi_tx_rx(struct cns3xxx_spi *hw, u8 tx_channel, u8 tx_eof,
+		     u32 tx_data, u32 * rx_data)
+{
+	u8 rx_channel;
+	u8 rx_eof;
+
+	while (!cns3xxx_spi_bus_idle(hw)) ;	// do nothing
+
+	while (!cns3xxx_spi_tx_buffer_empty(hw)) ;	// do nothing
+
+	SPI_TRANSMIT_CONTROL_REG &= ~(0x7);
+	SPI_TRANSMIT_CONTROL_REG |= (tx_channel & 0x3) | ((tx_eof & 0x1) << 2);
+
+	SPI_TRANSMIT_BUFFER_REG = tx_data;
+
+	while (!cns3xxx_spi_rx_buffer_full(hw)) ;	// do nothing
+
+	rx_channel = SPI_RECEIVE_CONTROL_REG & 0x3;
+	rx_eof = (SPI_RECEIVE_CONTROL_REG & (0x1 << 2)) ? 1 : 0;
+
+	*rx_data = SPI_RECEIVE_BUFFER_REG;
+
+	if ((tx_channel != rx_channel) || (tx_eof != rx_eof)) {
+		return 0;
+	} else {
+		return 1;
+	}
+}
+
+u8 cns3xxx_spi_tx(struct cns3xxx_spi *hw, u8 tx_channel, u8 tx_eof, u32 tx_data)
+{
+
+        while (!cns3xxx_spi_bus_idle(hw)) ;       // do nothing
+
+        while (!cns3xxx_spi_tx_buffer_empty(hw)) ;        // do nothing
+
+        SPI_TRANSMIT_CONTROL_REG &= ~(0x7);
+        SPI_TRANSMIT_CONTROL_REG |= (tx_channel & 0x3) | ((tx_eof & 0x1) << 2);
+
+        SPI_TRANSMIT_BUFFER_REG = tx_data;
+
+        return 1;
+}
+
+static inline struct cns3xxx_spi *to_hw(struct spi_device *sdev)
+{
+	return spi_master_get_devdata(sdev->master);
+}
+
+static int cns3xxx_spi_setup_transfer(struct spi_device *spi,
+				      struct spi_transfer *t)
+{
+	return 0;
+}
+
+static void cns3xxx_spi_chipselect(struct spi_device *spi, int value)
+{
+	struct cns3xxx_spi *hw = to_hw(spi);
+	unsigned int spi_config;
+
+	switch (value) {
+	case BITBANG_CS_INACTIVE:
+		break;
+
+	case BITBANG_CS_ACTIVE:
+		spi_config = SPI_CONFIGURATION_REG;
+
+		if (spi->mode & SPI_CPHA)
+			spi_config |= (0x1 << 13);
+		else
+			spi_config &= ~(0x1 << 13);
+
+		if (spi->mode & SPI_CPOL)
+			spi_config |= (0x1 << 14);
+		else
+			spi_config &= ~(0x1 << 14);
+
+		/* write new configration */
+		SPI_CONFIGURATION_REG = spi_config;
+
+		SPI_TRANSMIT_CONTROL_REG &= ~(0x7);
+		SPI_TRANSMIT_CONTROL_REG |= (spi->chip_select & 0x3);
+
+		break;
+	}
+}
+
+static int cns3xxx_spi_setup(struct spi_device *spi)
+{
+	if (!spi->bits_per_word)
+		spi->bits_per_word = 8;
+
+	return 0;
+}
+
+static int cns3xxx_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct cns3xxx_spi *hw = to_hw(spi);
+
+	dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n", t->tx_buf, t->rx_buf,
+		t->len);
+
+	hw->tx = t->tx_buf;
+	hw->rx = t->rx_buf;
+	hw->len = t->len;
+	hw->count = 0;
+	hw->last_in_message_list = t->last_in_message_list;
+
+	init_completion(&hw->done);
+
+	if (hw->tx) {
+		int i;
+		u32 rx_data;
+		for (i = 0; i < (hw->len - 1); i++) {
+			dev_dbg(&spi->dev,
+				"[SPI_CNS3XXX_DEBUG] hw->tx[%02d]: 0x%02x\n", i,
+				hw->tx[i]);
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 0, hw->tx[i],
+					  &rx_data);
+			if (hw->rx) {
+				hw->rx[i] = rx_data;
+				dev_dbg(&spi->dev,
+					"[SPI_CNS3XXX_DEBUG] hw->rx[%02d]: 0x%02x\n",
+					i, hw->rx[i]);
+			}
+		}
+
+		if (t->last_in_message_list) {
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 1, hw->tx[i],
+					  &rx_data);
+			if (hw->rx) {
+				hw->rx[i] = rx_data;
+				dev_dbg(&spi->dev,
+					"[SPI_CNS3XXX_DEBUG] hw->rx[%02d]: 0x%02x\n",
+					i, hw->rx[i]);
+			}
+		} else {
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 0, hw->tx[i],
+					  &rx_data);
+		}
+		goto done;
+	}
+
+	if (hw->rx) {
+		int i;
+		u32 rx_data;
+		for (i = 0; i < (hw->len - 1); i++) {
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 0, 0xff, &rx_data);
+			hw->rx[i] = rx_data;
+			dev_dbg(&spi->dev,
+				"[SPI_CNS3XXX_DEBUG] hw->rx[%02d]: 0x%02x\n", i,
+				hw->rx[i]);
+		}
+
+		if (t->last_in_message_list) {
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 1, 0xff, &rx_data);
+		} else {
+			cns3xxx_spi_tx_rx(hw, spi->chip_select, 0, 0xff, &rx_data);
+		}
+		hw->rx[i] = rx_data;
+		dev_dbg(&spi->dev, "[SPI_CNS3XXX_DEBUG] hw->rx[%02d]: 0x%02x\n",
+			i, hw->rx[i]);
+	}
+done:
+	return hw->len;
+}
+
+static void __init cns3xxx_spi_initial(struct cns3xxx_spi *hw)
+{
+	SPI_CONFIGURATION_REG = (((0x0 & 0x3) << 0) |	/* 8bits shift length */
+				 (0x0 << 9) |	/* SPI mode */
+				 (0x0 << 10) |	/* disable FIFO */
+				 (0x1 << 11) |	/* SPI master mode */
+				 (0x0 << 12) |	/* disable SPI loopback mode */
+				 (0x1 << 13) |	/* clock phase */
+				 (0x1 << 14) |	/* clock polarity */
+				 (0x0 << 24) |	/* disable - SPI data swap */
+				 (0x1 << 29) |	/* enable - 2IO Read mode */
+				 (0x0 << 30) |	/* disable - SPI high speed read for system boot up */
+				 (0x0 << 31));	/* disable - SPI */
+
+	/* Set SPI bit rate PCLK/2 */
+	SPI_BIT_RATE_CONTROL_REG = 0x1;
+
+	/* Set SPI Tx channel 0 */
+	SPI_TRANSMIT_CONTROL_REG = 0x0;
+
+	/* Set Tx FIFO Threshold, Tx FIFO has 2 words */
+	SPI_FIFO_TRANSMIT_CONFIG_REG &= ~(0x03 << 4);
+	SPI_FIFO_TRANSMIT_CONFIG_REG |= ((0x0 & 0x03) << 4);
+
+	/* Set Rx FIFO Threshold, Rx FIFO has 2 words */
+	SPI_FIFO_RECEIVE_CONFIG_REG &= ~(0x03 << 4);
+	SPI_FIFO_RECEIVE_CONFIG_REG |= ((0x0 & 0x03) << 4);
+
+	/* Disable all interrupt */
+	SPI_INTERRUPT_ENABLE_REG = 0x0;
+
+	/* Clear spurious interrupt sources */
+	SPI_INTERRUPT_STATUS_REG = (0x0F << 4);
+
+	/* Enable SPI */
+	SPI_CONFIGURATION_REG |= (0x1 << 31);
+
+	return;
+}
+
+static int cns3xxx_spi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct cns3xxx_spi *hw;
+	struct resource *res;
+	int err = 0;
+
+	printk("%s: setup CNS3XXX SPI Controller\n", __FUNCTION__);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	/* Allocate master with space for cns3xxx_spi */
+	master = spi_alloc_master(&pdev->dev, sizeof(struct cns3xxx_spi));
+	if (master == NULL) {
+		dev_err(&pdev->dev, "No memory for spi_master\n");
+		err = -ENOMEM;
+		goto err_nomem;
+	}
+
+	hw = spi_master_get_devdata(master);
+	memset(hw, 0, sizeof(struct cns3xxx_spi));
+
+	hw->master = spi_master_get(master);
+	hw->dev = &pdev->dev;
+
+	hw->base = devm_ioremap_resource(hw->dev, res);
+	if (IS_ERR(hw->base)) {
+		dev_err(hw->dev, "Unable to map registers\n");
+		err = PTR_ERR(hw->base);
+		goto err_register;
+	}
+
+	platform_set_drvdata(pdev, hw);
+	init_completion(&hw->done);
+
+	/* setup the master state. */
+
+	master->num_chipselect = 4;
+	master->bus_num = 1;
+
+	/* setup the state for the bitbang driver */
+
+	hw->bitbang.master = hw->master;
+	hw->bitbang.setup_transfer = cns3xxx_spi_setup_transfer;
+	hw->bitbang.chipselect = cns3xxx_spi_chipselect;
+	hw->bitbang.txrx_bufs = cns3xxx_spi_txrx;
+	hw->bitbang.master->setup = cns3xxx_spi_setup;
+
+	dev_dbg(hw->dev, "bitbang at %p\n", &hw->bitbang);
+
+	/* SPI controller initializations */
+	cns3xxx_spi_initial(hw);
+
+	/* register SPI controller */
+
+	err = spi_bitbang_start(&hw->bitbang);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to register SPI master\n");
+		goto err_register;
+	}
+
+	return 0;
+
+err_register:
+	spi_master_put(hw->master);;
+
+err_nomem:
+	return err;
+}
+
+static int cns3xxx_spi_remove(struct platform_device *dev)
+{
+	struct cns3xxx_spi *hw = platform_get_drvdata(dev);
+
+	platform_set_drvdata(dev, NULL);
+
+	spi_unregister_master(hw->master);
+
+	spi_master_put(hw->master);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int cns3xxx_spi_suspend(struct platform_device *pdev, pm_message_t msg)
+{
+	struct cns3xxx_spi *hw = platform_get_drvdata(pdev);
+
+	return 0;
+}
+
+static int cns3xxx_spi_resume(struct platform_device *pdev)
+{
+	struct cns3xxx_spi *hw = platform_get_drvdata(pdev);
+
+	return 0;
+}
+
+#else
+#define cns3xxx_spi_suspend	NULL
+#define cns3xxx_spi_resume	NULL
+#endif
+
+static struct platform_driver cns3xxx_spi_driver = {
+	.probe		= cns3xxx_spi_probe,
+	.remove		= cns3xxx_spi_remove,
+	.suspend	= cns3xxx_spi_suspend,
+	.resume		= cns3xxx_spi_resume,
+	.driver		= {
+		.name = "cns3xxx_spi",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init cns3xxx_spi_init(void)
+{
+	return platform_driver_register(&cns3xxx_spi_driver);
+}
+
+static void __exit cns3xxx_spi_exit(void)
+{
+	platform_driver_unregister(&cns3xxx_spi_driver);
+}
+
+module_init(cns3xxx_spi_init);
+module_exit(cns3xxx_spi_exit);
+
+MODULE_AUTHOR("Cavium Networks");
+MODULE_DESCRIPTION("CNS3XXX SPI Controller Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:cns3xxx_spi");
+
+EXPORT_SYMBOL_GPL(cns3xxx_spi_tx_rx);