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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: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
This commit is contained in:
Janusz Krzysztofik 2018-11-21 12:08:05 +01:00 committed by Miquel Raynal
parent 9773861304
commit 7416bd3500
1 changed files with 61 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

109
drivers/mtd/nand/raw/ams-delta.c
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@ -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;
}