1 files changed, 155 insertions, 82 deletions

diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c
index 8312182088c1..d66dab25df20 100644
--- a/drivers/mtd/nand/raw/ams-delta.c
+++ b/drivers/mtd/nand/raw/ams-delta.c
@@ -19,15 +19,17 @@
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/mtd/mtd.h>
+#include <linux/mtd/nand-gpio.h>
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/partitions.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
 
 /*
  * MTD structure for E3 (Delta)
  */
-struct ams_delta_nand {
+struct gpio_nand {
 	struct nand_controller	base;
 	struct nand_chip	nand_chip;
 	struct gpio_desc	*gpiod_rdy;
@@ -39,41 +41,20 @@ struct ams_delta_nand {
 	struct gpio_desc	*gpiod_cle;
 	struct gpio_descs	*data_gpiods;
 	bool			data_in;
+	unsigned int		tRP;
+	unsigned int		tWP;
+	u8			(*io_read)(struct gpio_nand *this);
+	void			(*io_write)(struct gpio_nand *this, u8 byte);
 };
 
-/*
- * Define partitions for flash devices
- */
-
-static const struct mtd_partition partition_info[] = {
-	{ .name		= "Kernel",
-	  .offset	= 0,
-	  .size		= 3 * SZ_1M + SZ_512K },
-	{ .name		= "u-boot",
-	  .offset	= 3 * SZ_1M + SZ_512K,
-	  .size		= SZ_256K },
-	{ .name		= "u-boot params",
-	  .offset	= 3 * SZ_1M + SZ_512K + SZ_256K,
-	  .size		= SZ_256K },
-	{ .name		= "Amstrad LDR",
-	  .offset	= 4 * SZ_1M,
-	  .size		= SZ_256K },
-	{ .name		= "File system",
-	  .offset	= 4 * SZ_1M + 1 * SZ_256K,
-	  .size		= 27 * SZ_1M },
-	{ .name		= "PBL reserved",
-	  .offset	= 32 * SZ_1M - 3 * SZ_256K,
-	  .size		=  3 * SZ_256K },
-};
-
-static void ams_delta_write_commit(struct ams_delta_nand *priv)
+static void gpio_nand_write_commit(struct gpio_nand *priv)
 {
-	gpiod_set_value(priv->gpiod_nwe, 0);
-	ndelay(40);
 	gpiod_set_value(priv->gpiod_nwe, 1);
+	ndelay(priv->tWP);
+	gpiod_set_value(priv->gpiod_nwe, 0);
 }
 
-static void ams_delta_io_write(struct ams_delta_nand *priv, u8 byte)
+static void gpio_nand_io_write(struct gpio_nand *priv, u8 byte)
 {
 	struct gpio_descs *data_gpiods = priv->data_gpiods;
 	DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, };
@@ -81,10 +62,10 @@ static void ams_delta_io_write(struct ams_delta_nand *priv, u8 byte)
 	gpiod_set_raw_array_value(data_gpiods->ndescs, data_gpiods->desc,
 				  data_gpiods->info, values);
 
-	ams_delta_write_commit(priv);
+	gpio_nand_write_commit(priv);
 }
 
-static void ams_delta_dir_output(struct ams_delta_nand *priv, u8 byte)
+static void gpio_nand_dir_output(struct gpio_nand *priv, u8 byte)
 {
 	struct gpio_descs *data_gpiods = priv->data_gpiods;
 	DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, };
@@ -94,30 +75,30 @@ static void ams_delta_dir_output(struct ams_delta_nand *priv, u8 byte)
 		gpiod_direction_output_raw(data_gpiods->desc[i],
 					   test_bit(i, values));
 
-	ams_delta_write_commit(priv);
+	gpio_nand_write_commit(priv);
 
 	priv->data_in = false;
 }
 
-static u8 ams_delta_io_read(struct ams_delta_nand *priv)
+static u8 gpio_nand_io_read(struct gpio_nand *priv)
 {
 	u8 res;
 	struct gpio_descs *data_gpiods = priv->data_gpiods;
 	DECLARE_BITMAP(values, BITS_PER_TYPE(res)) = { 0, };
 
-	gpiod_set_value(priv->gpiod_nre, 0);
-	ndelay(40);
+	gpiod_set_value(priv->gpiod_nre, 1);
+	ndelay(priv->tRP);
 
 	gpiod_get_raw_array_value(data_gpiods->ndescs, data_gpiods->desc,
 				  data_gpiods->info, values);
 
-	gpiod_set_value(priv->gpiod_nre, 1);
+	gpiod_set_value(priv->gpiod_nre, 0);
 
 	res = values[0];
 	return res;
 }
 
-static void ams_delta_dir_input(struct ams_delta_nand *priv)
+static void gpio_nand_dir_input(struct gpio_nand *priv)
 {
 	struct gpio_descs *data_gpiods = priv->data_gpiods;
 	int i;
@@ -128,68 +109,67 @@ static void ams_delta_dir_input(struct ams_delta_nand *priv)
 	priv->data_in = true;
 }
 
-static void ams_delta_write_buf(struct ams_delta_nand *priv, const u8 *buf,
-				int len)
+static void gpio_nand_write_buf(struct gpio_nand *priv, const u8 *buf, int len)
 {
 	int i = 0;
 
 	if (len > 0 && priv->data_in)
-		ams_delta_dir_output(priv, buf[i++]);
+		gpio_nand_dir_output(priv, buf[i++]);
 
 	while (i < len)
-		ams_delta_io_write(priv, buf[i++]);
+		priv->io_write(priv, buf[i++]);
 }
 
-static void ams_delta_read_buf(struct ams_delta_nand *priv, u8 *buf, int len)
+static void gpio_nand_read_buf(struct gpio_nand *priv, u8 *buf, int len)
 {
 	int i;
 
-	if (!priv->data_in)
-		ams_delta_dir_input(priv);
+	if (priv->data_gpiods && !priv->data_in)
+		gpio_nand_dir_input(priv);
 
 	for (i = 0; i < len; i++)
-		buf[i] = ams_delta_io_read(priv);
+		buf[i] = priv->io_read(priv);
 }
 
-static void ams_delta_ctrl_cs(struct ams_delta_nand *priv, bool assert)
+static void gpio_nand_ctrl_cs(struct gpio_nand *priv, bool assert)
 {
-	gpiod_set_value(priv->gpiod_nce, assert ? 0 : 1);
+	gpiod_set_value(priv->gpiod_nce, assert);
 }
 
-static int ams_delta_exec_op(struct nand_chip *this,
+static int gpio_nand_exec_op(struct nand_chip *this,
 			     const struct nand_operation *op, bool check_only)
 {
-	struct ams_delta_nand *priv = nand_get_controller_data(this);
+	struct gpio_nand *priv = nand_get_controller_data(this);
 	const struct nand_op_instr *instr;
 	int ret = 0;
 
 	if (check_only)
 		return 0;
 
-	ams_delta_ctrl_cs(priv, 1);
+	gpio_nand_ctrl_cs(priv, 1);
 
 	for (instr = op->instrs; instr < op->instrs + op->ninstrs; instr++) {
 		switch (instr->type) {
 		case NAND_OP_CMD_INSTR:
 			gpiod_set_value(priv->gpiod_cle, 1);
-			ams_delta_write_buf(priv, &instr->ctx.cmd.opcode, 1);
+			gpio_nand_write_buf(priv, &instr->ctx.cmd.opcode, 1);
 			gpiod_set_value(priv->gpiod_cle, 0);
 			break;
 
 		case NAND_OP_ADDR_INSTR:
 			gpiod_set_value(priv->gpiod_ale, 1);
-			ams_delta_write_buf(priv, instr->ctx.addr.addrs,
+			gpio_nand_write_buf(priv, instr->ctx.addr.addrs,
 					    instr->ctx.addr.naddrs);
 			gpiod_set_value(priv->gpiod_ale, 0);
 			break;
 
 		case NAND_OP_DATA_IN_INSTR:
-			ams_delta_read_buf(priv, instr->ctx.data.buf.in,
+			gpio_nand_read_buf(priv, instr->ctx.data.buf.in,
 					   instr->ctx.data.len);
 			break;
 
 		case NAND_OP_DATA_OUT_INSTR:
-			ams_delta_write_buf(priv, instr->ctx.data.buf.out,
+			gpio_nand_write_buf(priv, instr->ctx.data.buf.out,
 					    instr->ctx.data.len);
 			break;
 
@@ -206,28 +186,61 @@ static int ams_delta_exec_op(struct nand_chip *this,
 			break;
 	}
 
-	ams_delta_ctrl_cs(priv, 0);
+	gpio_nand_ctrl_cs(priv, 0);
 
 	return ret;
 }
 
-static const struct nand_controller_ops ams_delta_ops = {
-	.exec_op = ams_delta_exec_op,
+static int gpio_nand_setup_data_interface(struct nand_chip *this, int csline,
+					  const struct nand_data_interface *cf)
+{
+	struct gpio_nand *priv = nand_get_controller_data(this);
+	const struct nand_sdr_timings *sdr = nand_get_sdr_timings(cf);
+	struct device *dev = &nand_to_mtd(this)->dev;
+
+	if (IS_ERR(sdr))
+		return PTR_ERR(sdr);
+
+	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
+		return 0;
+
+	if (priv->gpiod_nre) {
+		priv->tRP = DIV_ROUND_UP(sdr->tRP_min, 1000);
+		dev_dbg(dev, "using %u ns read pulse width\n", priv->tRP);
+	}
+
+	priv->tWP = DIV_ROUND_UP(sdr->tWP_min, 1000);
+	dev_dbg(dev, "using %u ns write pulse width\n", priv->tWP);
+
+	return 0;
+}
+
+static const struct nand_controller_ops gpio_nand_ops = {
+	.exec_op = gpio_nand_exec_op,
+	.setup_data_interface = gpio_nand_setup_data_interface,
 };
 
 /*
  * Main initialization routine
  */
-static int ams_delta_init(struct platform_device *pdev)
+static int gpio_nand_probe(struct platform_device *pdev)
 {
-	struct ams_delta_nand *priv;
+	struct gpio_nand_platdata *pdata = dev_get_platdata(&pdev->dev);
+	const struct mtd_partition *partitions = NULL;
+	int num_partitions = 0;
+	struct gpio_nand *priv;
 	struct nand_chip *this;
 	struct mtd_info *mtd;
-	struct gpio_descs *data_gpiods;
+	int (*probe)(struct platform_device *pdev, struct gpio_nand *priv);
 	int err = 0;
 
+	if (pdata) {
+		partitions = pdata->parts;
+		num_partitions = pdata->num_parts;
+	}
+
 	/* Allocate memory for MTD device structure and private data */
-	priv = devm_kzalloc(&pdev->dev, sizeof(struct ams_delta_nand),
+	priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_nand),
 			    GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
@@ -238,6 +251,7 @@ static int ams_delta_init(struct platform_device *pdev)
 	mtd->dev.parent = &pdev->dev;
 
 	nand_set_controller_data(this, priv);
+	nand_set_flash_node(this, pdev->dev.of_node);
 
 	priv->gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN);
 	if (IS_ERR(priv->gpiod_rdy)) {
@@ -251,29 +265,33 @@ static int ams_delta_init(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, priv);
 
-	/* Set chip enabled, but  */
-	priv->gpiod_nwp = devm_gpiod_get(&pdev->dev, "nwp", GPIOD_OUT_HIGH);
+	/* Set chip enabled but write protected */
+	priv->gpiod_nwp = devm_gpiod_get_optional(&pdev->dev, "nwp",
+						  GPIOD_OUT_HIGH);
 	if (IS_ERR(priv->gpiod_nwp)) {
 		err = PTR_ERR(priv->gpiod_nwp);
 		dev_err(&pdev->dev, "NWP GPIO request failed (%d)\n", err);
 		return err;
 	}
 
-	priv->gpiod_nce = devm_gpiod_get(&pdev->dev, "nce", GPIOD_OUT_HIGH);
+	priv->gpiod_nce = devm_gpiod_get_optional(&pdev->dev, "nce",
+						  GPIOD_OUT_LOW);
 	if (IS_ERR(priv->gpiod_nce)) {
 		err = PTR_ERR(priv->gpiod_nce);
 		dev_err(&pdev->dev, "NCE GPIO request failed (%d)\n", err);
 		return err;
 	}
 
-	priv->gpiod_nre = devm_gpiod_get(&pdev->dev, "nre", GPIOD_OUT_HIGH);
+	priv->gpiod_nre = devm_gpiod_get_optional(&pdev->dev, "nre",
+						  GPIOD_OUT_LOW);
 	if (IS_ERR(priv->gpiod_nre)) {
 		err = PTR_ERR(priv->gpiod_nre);
 		dev_err(&pdev->dev, "NRE GPIO request failed (%d)\n", err);
 		return err;
 	}
 
-	priv->gpiod_nwe = devm_gpiod_get(&pdev->dev, "nwe", GPIOD_OUT_HIGH);
+	priv->gpiod_nwe = devm_gpiod_get_optional(&pdev->dev, "nwe",
+						  GPIOD_OUT_LOW);
 	if (IS_ERR(priv->gpiod_nwe)) {
 		err = PTR_ERR(priv->gpiod_nwe);
 		dev_err(&pdev->dev, "NWE GPIO request failed (%d)\n", err);
@@ -295,28 +313,62 @@ static int ams_delta_init(struct platform_device *pdev)
 	}
 
 	/* Request array of data pins, initialize them as input */
-	data_gpiods = devm_gpiod_get_array(&pdev->dev, "data", GPIOD_IN);
-	if (IS_ERR(data_gpiods)) {
-		err = PTR_ERR(data_gpiods);
+	priv->data_gpiods = devm_gpiod_get_array_optional(&pdev->dev, "data",
+							  GPIOD_IN);
+	if (IS_ERR(priv->data_gpiods)) {
+		err = PTR_ERR(priv->data_gpiods);
 		dev_err(&pdev->dev, "data GPIO request failed: %d\n", err);
 		return err;
 	}
-	priv->data_gpiods = data_gpiods;
-	priv->data_in = true;
+	if (priv->data_gpiods) {
+		if (!priv->gpiod_nwe) {
+			dev_err(&pdev->dev,
+				"mandatory NWE pin not provided by platform\n");
+			return -ENODEV;
+		}
 
-	/* Initialize the NAND controller object embedded in ams_delta_nand. */
-	priv->base.ops = &ams_delta_ops;
+		priv->io_read = gpio_nand_io_read;
+		priv->io_write = gpio_nand_io_write;
+		priv->data_in = true;
+	}
+
+	if (pdev->id_entry)
+		probe = (void *) pdev->id_entry->driver_data;
+	else
+		probe = of_device_get_match_data(&pdev->dev);
+	if (probe)
+		err = probe(pdev, priv);
+	if (err)
+		return err;
+
+	if (!priv->io_read || !priv->io_write) {
+		dev_err(&pdev->dev, "incomplete device configuration\n");
+		return -ENODEV;
+	}
+
+	/* Initialize the NAND controller object embedded in gpio_nand. */
+	priv->base.ops = &gpio_nand_ops;
 	nand_controller_init(&priv->base);
 	this->controller = &priv->base;
 
+	/*
+	 * FIXME: We should release write protection only after nand_scan() to
+	 * be on the safe side but we can't do that until we have a generic way
+	 * to assert/deassert WP from the core.  Even if the core shouldn't
+	 * write things in the nand_scan() path, it should have control on this
+	 * pin just in case we ever need to disable write protection during
+	 * chip detection/initialization.
+	 */
+	/* Release write protection */
+	gpiod_set_value(priv->gpiod_nwp, 0);
+
 	/* Scan to find existence of the device */
 	err = nand_scan(this, 1);
 	if (err)
 		return err;
 
 	/* Register the partitions */
-	err = mtd_device_register(mtd, partition_info,
-				  ARRAY_SIZE(partition_info));
+	err = mtd_device_register(mtd, partitions, num_partitions);
 	if (err)
 		goto err_nand_cleanup;
 
@@ -331,26 +383,47 @@ err_nand_cleanup:
 /*
  * Clean up routine
  */
-static int ams_delta_cleanup(struct platform_device *pdev)
+static int gpio_nand_remove(struct platform_device *pdev)
 {
-	struct ams_delta_nand *priv = platform_get_drvdata(pdev);
+	struct gpio_nand *priv = platform_get_drvdata(pdev);
 	struct mtd_info *mtd = nand_to_mtd(&priv->nand_chip);
 
+	/* Apply write protection */
+	gpiod_set_value(priv->gpiod_nwp, 1);
+
 	/* Unregister device */
 	nand_release(mtd_to_nand(mtd));
 
 	return 0;
 }
 
-static struct platform_driver ams_delta_nand_driver = {
-	.probe		= ams_delta_init,
-	.remove		= ams_delta_cleanup,
+static const struct of_device_id gpio_nand_of_id_table[] = {
+	{
+		/* sentinel */
+	},
+};
+MODULE_DEVICE_TABLE(of, gpio_nand_of_id_table);
+
+static const struct platform_device_id gpio_nand_plat_id_table[] = {
+	{
+		.name	= "ams-delta-nand",
+	}, {
+		/* sentinel */
+	},
+};
+MODULE_DEVICE_TABLE(platform, gpio_nand_plat_id_table);
+
+static struct platform_driver gpio_nand_driver = {
+	.probe		= gpio_nand_probe,
+	.remove		= gpio_nand_remove,
+	.id_table	= gpio_nand_plat_id_table,
 	.driver		= {
 		.name	= "ams-delta-nand",
+		.of_match_table = of_match_ptr(gpio_nand_of_id_table),
 	},
 };
 
-module_platform_driver(ams_delta_nand_driver);
+module_platform_driver(gpio_nand_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>");