[PATCH v3 7/8] nand: spi: Add generic SPI controller support

Peter Pan
2017-03-16T06:36:40Z

This commit supports to use generic spi controller
as spi nand controller.

Signed-off-by: Peter Pan <peterpandong@micron.com>
---
drivers/mtd/nand/spi/Kconfig | 2 +
drivers/mtd/nand/spi/Makefile | 1 +
drivers/mtd/nand/spi/controllers/Kconfig | 5 +
drivers/mtd/nand/spi/controllers/Makefile | 1 +
drivers/mtd/nand/spi/controllers/generic-spi.c | 158 +++++++++++++++++++++++++
5 files changed, 167 insertions(+)
create mode 100644 drivers/mtd/nand/spi/controllers/Kconfig
create mode 100644 drivers/mtd/nand/spi/controllers/Makefile
create mode 100644 drivers/mtd/nand/spi/controllers/generic-spi.c

diff --git a/drivers/mtd/nand/spi/Kconfig b/drivers/mtd/nand/spi/Kconfig
index d77c46e..6bd1c65 100644
--- a/drivers/mtd/nand/spi/Kconfig
+++ b/drivers/mtd/nand/spi/Kconfig
@@ -3,3 +3,5 @@ menuconfig MTD_SPI_NAND
depends on MTD_NAND
help
This is the framework for the SPI NAND device drivers.
+
+source "drivers/mtd/nand/spi/controllers/Kconfig"
diff --git a/drivers/mtd/nand/spi/Makefile b/drivers/mtd/nand/spi/Makefile
index db0b91b..6ad5f24 100644
--- a/drivers/mtd/nand/spi/Makefile
+++ b/drivers/mtd/nand/spi/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_MTD_SPI_NAND) += core.o
obj-$(CONFIG_MTD_SPI_NAND) += manufactures.o
obj-$(CONFIG_MTD_SPI_NAND) += micron.o
+obj-$(CONFIG_MTD_SPI_NAND) += controllers/
diff --git a/drivers/mtd/nand/spi/controllers/Kconfig b/drivers/mtd/nand/spi/controllers/Kconfig
new file mode 100644
index 0000000..8ab7023
--- /dev/null
+++ b/drivers/mtd/nand/spi/controllers/Kconfig
@@ -0,0 +1,5 @@
+config GENERIC_SPI_NAND
+ tristate "SPI NAND with generic SPI bus Support"
+ depends on MTD_SPI_NAND && SPI
+ help
+ This is to support SPI NAND device with generic SPI bus.
diff --git a/drivers/mtd/nand/spi/controllers/Makefile b/drivers/mtd/nand/spi/controllers/Makefile
new file mode 100644
index 0000000..46cbf29
--- /dev/null
+++ b/drivers/mtd/nand/spi/controllers/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_GENERIC_SPI_NAND) += generic-spi.o
diff --git a/drivers/mtd/nand/spi/controllers/generic-spi.c b/drivers/mtd/nand/spi/controllers/generic-spi.c
new file mode 100644
index 0000000..38b4a56
--- /dev/null
+++ b/drivers/mtd/nand/spi/controllers/generic-spi.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2009-2017 Micron Technology, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/spi/spi.h>
+#include <linux/mtd/spinand.h>
+
+/*
+ * generic_spinand_cmd_fn - to process a command to send to the SPI NAND
+ * by generic SPI bus
+ * @chip: SPI NAND device structure
+ * @op: SPI NAND operation descriptor
+ */
+static int generic_spinand_cmd_fn(struct spinand_device *chip,
+ struct spinand_op *op)
+{
+ struct spi_message message;
+ struct spi_transfer x[3];
+ struct spi_device *spi = spinand_get_controller_data(chip);
+
+ spi_message_init(&message);
+ memset(x, 0, sizeof(x));
+ x[0].len = 1;
+ x[0].tx_nbits = 1;
+ x[0].tx_buf = &op->cmd;
+ spi_message_add_tail(&x[0], &message);
+
+ if (op->n_addr + op->dummy_bytes) {
+ x[1].len = op->n_addr + op->dummy_bytes;
+ x[1].tx_nbits = op->addr_nbits;
+ x[1].tx_buf = op->addr;
+ spi_message_add_tail(&x[1], &message);
+ }
+ if (op->n_tx) {
+ x[2].len = op->n_tx;
+ x[2].tx_nbits = op->data_nbits;
+ x[2].tx_buf = op->tx_buf;
+ spi_message_add_tail(&x[2], &message);
+ } else if (op->n_rx) {
+ x[2].len = op->n_rx;
+ x[2].rx_nbits = op->data_nbits;
+ x[2].rx_buf = op->rx_buf;
+ spi_message_add_tail(&x[2], &message);
+ }
+ return spi_sync(spi, &message);
+}
+
+static struct spinand_controller_ops generic_spi_ops = {
+ .exec_op = generic_spinand_cmd_fn,
+};
+
+static int generic_spinand_probe(struct spi_device *spi)
+{
+ struct spinand_device *chip;
+ struct mtd_info *mtd;
+ struct spinand_controller *controller;
+ struct spinand_ecc_engine *ecc_engine;
+ int ret;
+ u32 max_speed_hz = spi->max_speed_hz;
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (!chip) {
+ ret = -ENOMEM;
+ goto err1;
+ }
+ mtd = spinand_to_mtd(chip);
+ controller = kzalloc(sizeof(*controller), GFP_KERNEL);
+ if (!controller) {
+ ret = -ENOMEM;
+ goto err2;
+ }
+ controller->ops = &generic_spi_ops;
+ controller->caps = SPINAND_CAP_RD_X1 | SPINAND_CAP_WR_X1;
+ if (spi->mode & SPI_RX_QUAD)
+ controller->caps |= SPINAND_CAP_RD_QUAD | SPINAND_CAP_RD_X4;
+ if (spi->mode & SPI_RX_DUAL)
+ controller->caps |= SPINAND_CAP_RD_DUAL | SPINAND_CAP_RD_X2;
+ if (spi->mode & SPI_TX_QUAD)
+ controller->caps |= SPINAND_CAP_WR_QUAD | SPINAND_CAP_WR_X4;
+ if (spi->mode & SPI_TX_DUAL)
+ controller->caps |= SPINAND_CAP_WR_DUAL | SPINAND_CAP_WR_X2;
+ chip->controller = controller;
+ ecc_engine = kzalloc(sizeof(*ecc_engine), GFP_KERNEL);
+ if (!ecc_engine) {
+ ret = -ENOMEM;
+ goto err3;
+ }
+ ecc_engine->mode = SPINAND_ECC_ONDIE;
+ chip->ecc.engine = ecc_engine;
+ spinand_set_controller_data(chip, spi);
+ spi_set_drvdata(spi, chip);
+ spi->max_speed_hz = min_t(int, 25000000, max_speed_hz);
+ ret = spinand_detect(chip);
+ if (ret)
+ goto err4;
+
+ spi->max_speed_hz = max_speed_hz;
+ ret = spinand_init(chip);
+ if (ret)
+ goto err5;
+
+ mtd_set_of_node(mtd, spi->dev.of_node);
+
+ ret = mtd_device_register(mtd, NULL, 0);
+ if (!ret)
+ return 0;
+
+err5:
+ spinand_cleanup(chip);
+err4:
+ kfree(ecc_engine);
+err3:
+ kfree(controller);
+err2:
+ kfree(chip);
+err1:
+ return ret;
+}
+
+static int generic_spinand_remove(struct spi_device *spi)
+{
+ struct spinand_device *chip = spi_get_drvdata(spi);
+ struct mtd_info *mtd = spinand_to_mtd(chip);
+
+ mtd_device_unregister(mtd);
+ spinand_cleanup(chip);
+ kfree(chip->ecc.engine);
+ kfree(chip->controller);
+ kfree(chip);
+
+ return 0;
+}
+
+static struct spi_driver generic_spinand_driver = {
+ .driver = {
+ .name = "generic_spinand",
+ .owner = THIS_MODULE,
+ },
+ .probe = generic_spinand_probe,
+ .remove = generic_spinand_remove,
+};
+module_spi_driver(generic_spinand_driver);
+
+MODULE_DESCRIPTION("Generic SPI controller to support SPI NAND");
+MODULE_AUTHOR("Peter Pan<peterpandong@micron.com>");
+MODULE_LICENSE("GPL v2");
--
1.9.1