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: Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>
---
drivers/mtd/nand/raw/ams-delta.c | 32 ++++++++++++++++++++++++++------
1 file changed, 26 insertions(+), 6 deletions(-)
diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c
index a68b7006ed69..9e659984bf59 100644
--- a/drivers/mtd/nand/raw/ams-delta.c
+++ b/drivers/mtd/nand/raw/ams-delta.c
@@ -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;
}
- 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;
+ }
+
+ 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);
--
2.24.1
