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-rw-r--r--target/linux/cns3xxx/files/drivers/spi/spi-cns3xxx.c448
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);