Commit 2b1dcee3 authored by Janusz Krzysztofik's avatar Janusz Krzysztofik Committed by Miquel Raynal
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mtd: rawnand: ams-delta: Make the driver custom I/O ready 



In order to be merged with "gpio-nand", the driver must support custom
(non-GPIO) I/O accessors.

Allow platforms to omit data GPIO port as well as NWE pin info from
device setup.  For the driver to still work on such platform, custom
I/O accessors as well as a custom probe function which initialises the
driver private structure with those accessors must be added to the
driver.

Signed-off-by: default avatarJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-14-jmkrzyszt@gmail.com
parent edfd8d9c

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

+26 −6
Original line number Diff line number Diff line
@@ -43,6 +43,9 @@ struct ams_delta_nand { 
	bool			data_in;

	unsigned int		tRP;

	unsigned int		tWP;

	u8			(*io_read)(struct ams_delta_nand *this);

	void			(*io_write)(struct ams_delta_nand *this,

					    u8 byte);

};



static void ams_delta_write_commit(struct ams_delta_nand *priv)
@@ -116,18 +119,18 @@ static void ams_delta_write_buf(struct ams_delta_nand *priv, const u8 *buf, 
		ams_delta_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)

{

	int i;



	if (!priv->data_in)

	if (priv->data_gpiods && !priv->data_in)

		ams_delta_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)
@@ -289,7 +292,8 @@ static int ams_delta_init(struct platform_device *pdev) 
		return err;

	}



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

	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);
@@ -311,13 +315,24 @@ static int ams_delta_init(struct platform_device *pdev) 
	}



	/* Request array of data pins, initialize them as input */

	priv->data_gpiods = devm_gpiod_get_array(&pdev->dev, "data", GPIOD_IN);

	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;

	}

	if (priv->data_gpiods) {

		if (!priv->gpiod_nwe) {

			dev_err(&pdev->dev,

				"mandatory NWE pin not provided by platform\n");

			return -ENODEV;

		}



		priv->io_read = ams_delta_io_read;

		priv->io_write = ams_delta_io_write;

		priv->data_in = true;

	}



	if (pdev->id_entry)

		probe = (void *) pdev->id_entry->driver_data;
@@ -328,6 +343,11 @@ static int ams_delta_init(struct platform_device *pdev) 
	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 ams_delta_nand. */

	priv->base.ops = &ams_delta_ops;

	nand_controller_init(&priv->base);

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