--- /dev/null
+/**
+ * NAND flash driver for Broadcom Secondary Memory Interface
+ *
+ * Written by Luke Wren <luke@raspberrypi.org>
+ * Copyright (c) 2015, Raspberry Pi (Trading) Ltd.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions, and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ * to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2, as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <linux/broadcom/bcm2835_smi.h>
+
+#define DEVICE_NAME "bcm2835-smi-nand"
+#define DRIVER_NAME "smi-nand-bcm2835"
+
+struct bcm2835_smi_nand_host {
+ struct bcm2835_smi_instance *smi_inst;
+ struct nand_chip nand_chip;
+ struct mtd_info mtd;
+ struct device *dev;
+};
+
+/****************************************************************************
+*
+* NAND functionality implementation
+*
+****************************************************************************/
+
+#define SMI_NAND_CLE_PIN 0x01
+#define SMI_NAND_ALE_PIN 0x02
+
+static inline void bcm2835_smi_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
+ unsigned int ctrl)
+{
+ uint32_t cmd32 = cmd;
+ uint32_t addr = ~(SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
+ struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+ struct bcm2835_smi_instance *inst = host->smi_inst;
+
+ if (ctrl & NAND_CLE)
+ addr |= SMI_NAND_CLE_PIN;
+ if (ctrl & NAND_ALE)
+ addr |= SMI_NAND_ALE_PIN;
+ /* Lower ALL the CS pins! */
+ if (ctrl & NAND_NCE)
+ addr &= (SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
+
+ bcm2835_smi_set_address(inst, addr);
+
+ if (cmd != NAND_CMD_NONE)
+ bcm2835_smi_write_buf(inst, &cmd32, 1);
+}
+
+static inline uint8_t bcm2835_smi_nand_read_byte(struct mtd_info *mtd)
+{
+ uint8_t byte;
+ struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+ struct bcm2835_smi_instance *inst = host->smi_inst;
+
+ bcm2835_smi_read_buf(inst, &byte, 1);
+ return byte;
+}
+
+static inline void bcm2835_smi_nand_write_byte(struct mtd_info *mtd,
+ uint8_t byte)
+{
+ struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+ struct bcm2835_smi_instance *inst = host->smi_inst;
+
+ bcm2835_smi_write_buf(inst, &byte, 1);
+}
+
+static inline void bcm2835_smi_nand_write_buf(struct mtd_info *mtd,
+ const uint8_t *buf, int len)
+{
+ struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+ struct bcm2835_smi_instance *inst = host->smi_inst;
+
+ bcm2835_smi_write_buf(inst, buf, len);
+}
+
+static inline void bcm2835_smi_nand_read_buf(struct mtd_info *mtd,
+ uint8_t *buf, int len)
+{
+ struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+ struct bcm2835_smi_instance *inst = host->smi_inst;
+
+ bcm2835_smi_read_buf(inst, buf, len);
+}
+
+/****************************************************************************
+*
+* Probe and remove functions
+*
+***************************************************************************/
+
+static int bcm2835_smi_nand_probe(struct platform_device *pdev)
+{
+ struct bcm2835_smi_nand_host *host;
+ struct nand_chip *this;
+ struct mtd_info *mtd;
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node, *smi_node;
+ struct mtd_part_parser_data ppdata;
+ struct smi_settings *smi_settings;
+ struct bcm2835_smi_instance *smi_inst;
+ int ret = -ENXIO;
+
+ if (!node) {
+ dev_err(dev, "No device tree node supplied!");
+ return -EINVAL;
+ }
+
+ smi_node = of_parse_phandle(node, "smi_handle", 0);
+
+ /* Request use of SMI peripheral: */
+ smi_inst = bcm2835_smi_get(smi_node);
+
+ if (!smi_inst) {
+ dev_err(dev, "Could not register with SMI.");
+ return -EPROBE_DEFER;
+ }
+
+ /* Set SMI timing and bus width */
+
+ smi_settings = bcm2835_smi_get_settings_from_regs(smi_inst);
+
+ smi_settings->data_width = SMI_WIDTH_8BIT;
+ smi_settings->read_setup_time = 2;
+ smi_settings->read_hold_time = 1;
+ smi_settings->read_pace_time = 1;
+ smi_settings->read_strobe_time = 3;
+
+ smi_settings->write_setup_time = 2;
+ smi_settings->write_hold_time = 1;
+ smi_settings->write_pace_time = 1;
+ smi_settings->write_strobe_time = 3;
+
+ bcm2835_smi_set_regs_from_settings(smi_inst);
+
+ host = devm_kzalloc(dev, sizeof(struct bcm2835_smi_nand_host),
+ GFP_KERNEL);
+ if (!host)
+ return -ENOMEM;
+
+ host->dev = dev;
+ host->smi_inst = smi_inst;
+
+ platform_set_drvdata(pdev, host);
+
+ /* Link the structures together */
+
+ this = &host->nand_chip;
+ mtd = &host->mtd;
+ mtd->priv = this;
+ mtd->owner = THIS_MODULE;
+ mtd->dev.parent = dev;
+ mtd->name = DRIVER_NAME;
+
+ /* 20 us command delay time... */
+ this->chip_delay = 20;
+
+ this->priv = host;
+ this->cmd_ctrl = bcm2835_smi_nand_cmd_ctrl;
+ this->read_byte = bcm2835_smi_nand_read_byte;
+ this->write_byte = bcm2835_smi_nand_write_byte;
+ this->write_buf = bcm2835_smi_nand_write_buf;
+ this->read_buf = bcm2835_smi_nand_read_buf;
+
+ this->ecc.mode = NAND_ECC_SOFT;
+
+ /* Should never be accessed directly: */
+
+ this->IO_ADDR_R = (void *)0xdeadbeef;
+ this->IO_ADDR_W = (void *)0xdeadbeef;
+
+ /* First scan to find the device and get the page size */
+
+ if (nand_scan_ident(mtd, 1, NULL))
+ return -ENXIO;
+
+ /* Second phase scan */
+
+ if (nand_scan_tail(mtd))
+ return -ENXIO;
+
+ ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
+ if (!ret)
+ return 0;
+
+ nand_release(mtd);
+ return -EINVAL;
+}
+
+static int bcm2835_smi_nand_remove(struct platform_device *pdev)
+{
+ struct bcm2835_smi_nand_host *host = platform_get_drvdata(pdev);
+
+ nand_release(&host->mtd);
+
+ return 0;
+}
+
+/****************************************************************************
+*
+* Register the driver with device tree
+*
+***************************************************************************/
+
+static const struct of_device_id bcm2835_smi_nand_of_match[] = {
+ {.compatible = "brcm,bcm2835-smi-nand",},
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, bcm2835_smi_nand_of_match);
+
+static struct platform_driver bcm2835_smi_nand_driver = {
+ .probe = bcm2835_smi_nand_probe,
+ .remove = bcm2835_smi_nand_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = bcm2835_smi_nand_of_match,
+ },
+};
+
+module_platform_driver(bcm2835_smi_nand_driver);
+
+MODULE_ALIAS("platform:smi-nand-bcm2835");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION
+ ("Driver for NAND chips using Broadcom Secondary Memory Interface");
+MODULE_AUTHOR("Luke Wren <luke@raspberrypi.org>");
projects / mirror_ubuntu-zesty-kernel.git / commitdiff