Commit 7416bd35 authored by Janusz Krzysztofik's avatar Janusz Krzysztofik Committed by Miquel Raynal
Browse files

mtd: rawnand: ams-delta: Use GPIO API for data I/O 



Don't readw()/writew() data directly from/to GPIO port which is under
control of gpio-omap driver, use GPIO consumer API instead.

The driver should now work with any 8-bit bidirectional GPIO port, not
only OMAP.

Signed-off-by: default avatarJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: default avatarBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
parent 97738613

drivers/mtd/nand/raw/ams-delta.c

+61 −48
Original line number Diff line number Diff line
@@ -18,11 +18,10 @@ 
#include <linux/module.h>

#include <linux/delay.h>

#include <linux/gpio/consumer.h>

#include <linux/io.h>

#include <linux/mtd/mtd.h>

#include <linux/mtd/rawnand.h>

#include <linux/mtd/partitions.h>

#include <linux/platform_data/gpio-omap.h>

#include <linux/platform_device.h>

#include <linux/sizes.h>



/*
@@ -38,7 +37,7 @@ struct ams_delta_nand { 
	struct gpio_desc	*gpiod_nwe;

	struct gpio_desc	*gpiod_ale;

	struct gpio_desc	*gpiod_cle;

	void __iomem		*io_base;

	struct gpio_descs	*data_gpiods;

	bool			data_in;

};
@@ -67,42 +66,78 @@ static const struct mtd_partition partition_info[] = { 
	  .size		=  3 * SZ_256K },

};



static void ams_delta_io_write(struct ams_delta_nand *priv, u8 byte)

static void ams_delta_write_commit(struct ams_delta_nand *priv)

{

	writew(byte, priv->io_base + OMAP_MPUIO_OUTPUT);

	gpiod_set_value(priv->gpiod_nwe, 0);

	ndelay(40);

	gpiod_set_value(priv->gpiod_nwe, 1);

}



static void ams_delta_io_write(struct ams_delta_nand *priv, u8 byte)

{

	struct gpio_descs *data_gpiods = priv->data_gpiods;

	DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, };



	gpiod_set_raw_array_value(data_gpiods->ndescs, data_gpiods->desc,

				  data_gpiods->info, values);



	ams_delta_write_commit(priv);

}



static void ams_delta_dir_output(struct ams_delta_nand *priv, u8 byte)

{

	struct gpio_descs *data_gpiods = priv->data_gpiods;

	DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, };

	int i;



	for (i = 0; i < data_gpiods->ndescs; i++)

		gpiod_direction_output_raw(data_gpiods->desc[i],

					   test_bit(i, values));



	ams_delta_write_commit(priv);



	priv->data_in = false;

}



static u8 ams_delta_io_read(struct ams_delta_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);

	res = readw(priv->io_base + OMAP_MPUIO_INPUT_LATCH);



	gpiod_get_raw_array_value(data_gpiods->ndescs, data_gpiods->desc,

				  data_gpiods->info, values);



	gpiod_set_value(priv->gpiod_nre, 1);



	res = values[0];

	return res;

}



static void ams_delta_dir_input(struct ams_delta_nand *priv, bool in)

static void ams_delta_dir_input(struct ams_delta_nand *priv)

{

	writew(in ? ~0 : 0, priv->io_base + OMAP_MPUIO_IO_CNTL);

	priv->data_in = in;

	struct gpio_descs *data_gpiods = priv->data_gpiods;

	int i;



	for (i = 0; i < data_gpiods->ndescs; i++)

		gpiod_direction_input(data_gpiods->desc[i]);



	priv->data_in = true;

}



static void ams_delta_write_buf(struct ams_delta_nand *priv, const u8 *buf,

				int len)

{

	int i;

	int i = 0;



	if (priv->data_in)

		ams_delta_dir_input(priv, false);

	if (len > 0 && priv->data_in)

		ams_delta_dir_output(priv, buf[i++]);



	for (i = 0; i < len; i++)

		ams_delta_io_write(priv, buf[i]);

	while (i < len)

		ams_delta_io_write(priv, buf[i++]);

}



static void ams_delta_read_buf(struct ams_delta_nand *priv, u8 *buf, int len)
@@ -110,7 +145,7 @@ static void ams_delta_read_buf(struct ams_delta_nand *priv, u8 *buf, int len) 
	int i;



	if (!priv->data_in)

		ams_delta_dir_input(priv, true);

		ams_delta_dir_input(priv);



	for (i = 0; i < len; i++)

		buf[i] = ams_delta_io_read(priv);
@@ -188,14 +223,9 @@ static int ams_delta_init(struct platform_device *pdev) 
	struct ams_delta_nand *priv;

	struct nand_chip *this;

	struct mtd_info *mtd;

	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	void __iomem *io_base;

	struct gpio_descs *data_gpiods;

	int err = 0;



	if (!res)

		return -ENXIO;



	/* Allocate memory for MTD device structure and private data */

	priv = devm_kzalloc(&pdev->dev, sizeof(struct ams_delta_nand),

			    GFP_KERNEL);
@@ -207,25 +237,13 @@ static int ams_delta_init(struct platform_device *pdev) 
	mtd = nand_to_mtd(this);

	mtd->dev.parent = &pdev->dev;



	/*

	 * Don't try to request the memory region from here,

	 * it should have been already requested from the

	 * gpio-omap driver and requesting it again would fail.

	 */

	io_base = ioremap(res->start, resource_size(res));

	if (!io_base) {

		dev_err(&pdev->dev, "ioremap failed\n");

		return -EIO;

	}



	priv->io_base = io_base;

	nand_set_controller_data(this, priv);



	priv->gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN);

	if (IS_ERR(priv->gpiod_rdy)) {

		err = PTR_ERR(priv->gpiod_rdy);

		dev_warn(&pdev->dev, "RDY GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	this->ecc.mode = NAND_ECC_SOFT;
@@ -238,42 +256,42 @@ static int ams_delta_init(struct platform_device *pdev) 
	if (IS_ERR(priv->gpiod_nwp)) {

		err = PTR_ERR(priv->gpiod_nwp);

		dev_err(&pdev->dev, "NWP GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	priv->gpiod_nce = devm_gpiod_get(&pdev->dev, "nce", GPIOD_OUT_HIGH);

	if (IS_ERR(priv->gpiod_nce)) {

		err = PTR_ERR(priv->gpiod_nce);

		dev_err(&pdev->dev, "NCE GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	priv->gpiod_nre = devm_gpiod_get(&pdev->dev, "nre", GPIOD_OUT_HIGH);

	if (IS_ERR(priv->gpiod_nre)) {

		err = PTR_ERR(priv->gpiod_nre);

		dev_err(&pdev->dev, "NRE GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	priv->gpiod_nwe = devm_gpiod_get(&pdev->dev, "nwe", GPIOD_OUT_HIGH);

	if (IS_ERR(priv->gpiod_nwe)) {

		err = PTR_ERR(priv->gpiod_nwe);

		dev_err(&pdev->dev, "NWE GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	priv->gpiod_ale = devm_gpiod_get(&pdev->dev, "ale", GPIOD_OUT_LOW);

	if (IS_ERR(priv->gpiod_ale)) {

		err = PTR_ERR(priv->gpiod_ale);

		dev_err(&pdev->dev, "ALE GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	priv->gpiod_cle = devm_gpiod_get(&pdev->dev, "cle", GPIOD_OUT_LOW);

	if (IS_ERR(priv->gpiod_cle)) {

		err = PTR_ERR(priv->gpiod_cle);

		dev_err(&pdev->dev, "CLE GPIO request failed (%d)\n", err);

		goto err_unmap;

		return err;

	}



	/* Request array of data pins, initialize them as input */
@@ -281,8 +299,9 @@ static int ams_delta_init(struct platform_device *pdev) 
	if (IS_ERR(data_gpiods)) {

		err = PTR_ERR(data_gpiods);

		dev_err(&pdev->dev, "data GPIO request failed: %d\n", err);

		goto err_unmap;

		return err;

	}

	priv->data_gpiods = data_gpiods;

	priv->data_in = true;



	/* Initialize the NAND controller object embedded in ams_delta_nand. */
@@ -293,7 +312,7 @@ static int ams_delta_init(struct platform_device *pdev) 
	/* Scan to find existence of the device */

	err = nand_scan(this, 1);

	if (err)

		goto err_unmap;

		return err;



	/* Register the partitions */

	err = mtd_device_register(mtd, partition_info,
@@ -306,9 +325,6 @@ static int ams_delta_init(struct platform_device *pdev) 
err_nand_cleanup:

	nand_cleanup(this);



err_unmap:

	iounmap(io_base);



	return err;

}
@@ -319,13 +335,10 @@ static int ams_delta_cleanup(struct platform_device *pdev) 
{

	struct ams_delta_nand *priv = platform_get_drvdata(pdev);

	struct mtd_info *mtd = nand_to_mtd(&priv->nand_chip);

	void __iomem *io_base = priv->io_base;



	/* Release resources, unregister device */

	/* Unregister device */

	nand_release(mtd_to_nand(mtd));



	iounmap(io_base);



	return 0;

}

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