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Diffstat (limited to 'target/linux/oxnas/files/drivers/mtd/nand/oxnas_nand.c')
-rw-r--r--target/linux/oxnas/files/drivers/mtd/nand/oxnas_nand.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/target/linux/oxnas/files/drivers/mtd/nand/oxnas_nand.c b/target/linux/oxnas/files/drivers/mtd/nand/oxnas_nand.c
new file mode 100644
index 0000000..55eb009
--- /dev/null
+++ b/target/linux/oxnas/files/drivers/mtd/nand/oxnas_nand.c
@@ -0,0 +1,102 @@
+/*
+ * This program 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.
+ */
+
+#include <linux/module.h>
+#include <linux/mtd/nand.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <mach/utils.h>
+
+/* nand commands */
+#define NAND_CMD_ALE BIT(18)
+#define NAND_CMD_CLE BIT(19)
+#define NAND_CMD_CS 0
+#define NAND_CMD_RESET 0xff
+#define NAND_CMD (NAND_CMD_CS | NAND_CMD_CLE)
+#define NAND_ADDR (NAND_CMD_CS | NAND_CMD_ALE)
+#define NAND_DATA (NAND_CMD_CS)
+
+static void oxnas_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+ struct nand_chip *this = mtd->priv;
+ unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
+
+ if (ctrl & NAND_CTRL_CHANGE) {
+ nandaddr &= ~(NAND_CMD | NAND_ADDR);
+ if (ctrl & NAND_CLE)
+ nandaddr |= NAND_CMD;
+ else if (ctrl & NAND_ALE)
+ nandaddr |= NAND_ADDR;
+ this->IO_ADDR_W = (void __iomem *) nandaddr;
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ writeb(cmd, (void __iomem *) nandaddr);
+}
+
+static int oxnas_nand_probe(struct platform_device *pdev)
+{
+ /* enable clock and release static block reset */
+ struct clk *clk = of_clk_get(pdev->dev.of_node, 0);
+
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ clk_prepare_enable(clk);
+ device_reset(&pdev->dev);
+
+ return 0;
+}
+
+/* allow users to override the partition in DT using the cmdline */
+static const char * part_probes[] = { "cmdlinepart", "ofpart", NULL };
+
+static struct platform_nand_data oxnas_nand_data = {
+ .chip = {
+ .nr_chips = 1,
+ .chip_delay = 30,
+ .part_probe_types = part_probes,
+ },
+ .ctrl = {
+ .probe = oxnas_nand_probe,
+ .cmd_ctrl = oxnas_cmd_ctrl,
+ }
+};
+
+/*
+ * Try to find the node inside the DT. If it is available attach out
+ * platform_nand_data
+ */
+static int __init oxnas_register_nand(void)
+{
+ struct device_node *node;
+ struct platform_device *pdev;
+
+ node = of_find_compatible_node(NULL, NULL, "plxtech,nand-nas782x");
+ if (!node)
+ return -ENOENT;
+ pdev = of_find_device_by_node(node);
+ if (!pdev)
+ return -EINVAL;
+ pdev->dev.platform_data = &oxnas_nand_data;
+ of_node_put(node);
+ return 0;
+}
+
+subsys_initcall(oxnas_register_nand);
+
+static const struct of_device_id oxnas_nand_ids[] = {
+ { .compatible = "plxtech,nand-nas782x"},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, oxnas_nand_ids);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ma Haijun");
+MODULE_DESCRIPTION("NAND glue for Oxnas platforms");
+MODULE_ALIAS("platform:oxnas_nand");