[RFC PATCH 1/8] mtd: rawnand: ams-delta: Use private structure

From: Janusz Krzysztofik
Date: Wed Jul 18 2018 - 19:56:58 EST


Introduce a driver private structure and allocate it on device probe.
Use it for storing nand_chip structure, GPIO descriptors prevoiusly
stored in static variables as well as io_base pointer previously passed
as nand controller data or platform driver data. Subsequent patches
may populate the structure with more members as needed.

While at it, fix missing mtd->dev.parent and drop useless mtd->owner.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>
---
drivers/mtd/nand/raw/ams-delta.c | 126 +++++++++++++++++++++------------------
1 file changed, 69 insertions(+), 57 deletions(-)

diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c
index 2a8872ebd14a..48233d638d2a 100644
--- a/drivers/mtd/nand/raw/ams-delta.c
+++ b/drivers/mtd/nand/raw/ams-delta.c
@@ -34,14 +34,18 @@
/*
* MTD structure for E3 (Delta)
*/
-static struct mtd_info *ams_delta_mtd = NULL;
-static struct gpio_desc *gpiod_rdy;
-static struct gpio_desc *gpiod_nce;
-static struct gpio_desc *gpiod_nre;
-static struct gpio_desc *gpiod_nwp;
-static struct gpio_desc *gpiod_nwe;
-static struct gpio_desc *gpiod_ale;
-static struct gpio_desc *gpiod_cle;
+
+struct ams_delta_nand {
+ struct nand_chip nand_chip;
+ struct gpio_desc *gpiod_rdy;
+ struct gpio_desc *gpiod_nce;
+ struct gpio_desc *gpiod_nre;
+ struct gpio_desc *gpiod_nwp;
+ struct gpio_desc *gpiod_nwe;
+ struct gpio_desc *gpiod_ale;
+ struct gpio_desc *gpiod_cle;
+ void __iomem *io_base;
+};

/*
* Define partitions for flash devices
@@ -71,26 +75,28 @@ static const struct mtd_partition partition_info[] = {
static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte)
{
struct nand_chip *this = mtd_to_nand(mtd);
- void __iomem *io_base = (void __iomem *)nand_get_controller_data(this);
+ struct ams_delta_nand *priv = nand_get_controller_data(this);
+ void __iomem *io_base = priv->io_base;

writew(0, io_base + OMAP_MPUIO_IO_CNTL);
writew(byte, this->IO_ADDR_W);
- gpiod_set_value(gpiod_nwe, 0);
+ gpiod_set_value(priv->gpiod_nwe, 0);
ndelay(40);
- gpiod_set_value(gpiod_nwe, 1);
+ gpiod_set_value(priv->gpiod_nwe, 1);
}

static u_char ams_delta_read_byte(struct mtd_info *mtd)
{
u_char res;
struct nand_chip *this = mtd_to_nand(mtd);
- void __iomem *io_base = (void __iomem *)nand_get_controller_data(this);
+ struct ams_delta_nand *priv = nand_get_controller_data(this);
+ void __iomem *io_base = priv->io_base;

- gpiod_set_value(gpiod_nre, 0);
+ gpiod_set_value(priv->gpiod_nre, 0);
ndelay(40);
writew(~0, io_base + OMAP_MPUIO_IO_CNTL);
res = readw(this->IO_ADDR_R);
- gpiod_set_value(gpiod_nre, 1);
+ gpiod_set_value(priv->gpiod_nre, 1);

return res;
}
@@ -123,11 +129,13 @@ static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len)
static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
+ struct nand_chip *this = mtd_to_nand(mtd);
+ struct ams_delta_nand *priv = nand_get_controller_data(this);

if (ctrl & NAND_CTRL_CHANGE) {
- gpiod_set_value(gpiod_nce, !(ctrl & NAND_NCE));
- gpiod_set_value(gpiod_cle, !!(ctrl & NAND_CLE));
- gpiod_set_value(gpiod_ale, !!(ctrl & NAND_ALE));
+ gpiod_set_value(priv->gpiod_nce, !(ctrl & NAND_NCE));
+ gpiod_set_value(priv->gpiod_cle, !!(ctrl & NAND_CLE));
+ gpiod_set_value(priv->gpiod_ale, !!(ctrl & NAND_ALE));
}

if (cmd != NAND_CMD_NONE)
@@ -136,7 +144,10 @@ static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd,

static int ams_delta_nand_ready(struct mtd_info *mtd)
{
- return gpiod_get_value(gpiod_rdy);
+ struct nand_chip *this = mtd_to_nand(mtd);
+ struct ams_delta_nand *priv = nand_get_controller_data(this);
+
+ return gpiod_get_value(priv->gpiod_rdy);
}


@@ -145,7 +156,9 @@ static int ams_delta_nand_ready(struct mtd_info *mtd)
*/
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;
int err = 0;
@@ -154,15 +167,16 @@ static int ams_delta_init(struct platform_device *pdev)
return -ENXIO;

/* Allocate memory for MTD device structure and private data */
- this = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
- if (!this) {
+ priv = devm_kzalloc(&pdev->dev, sizeof(struct ams_delta_nand),
+ GFP_KERNEL);
+ if (!priv) {
pr_warn("Unable to allocate E3 NAND MTD device structure.\n");
- err = -ENOMEM;
- goto out;
+ return -ENOMEM;
}
+ this = &priv->nand_chip;

- ams_delta_mtd = nand_to_mtd(this);
- ams_delta_mtd->owner = THIS_MODULE;
+ mtd = nand_to_mtd(this);
+ mtd->dev.parent = &pdev->dev;

/*
* Don't try to request the memory region from here,
@@ -177,7 +191,8 @@ static int ams_delta_init(struct platform_device *pdev)
goto out_free;
}

- nand_set_controller_data(this, (void *)io_base);
+ priv->io_base = io_base;
+ nand_set_controller_data(this, priv);

/* Set address of NAND IO lines */
this->IO_ADDR_R = io_base + OMAP_MPUIO_INPUT_LATCH;
@@ -187,14 +202,14 @@ static int ams_delta_init(struct platform_device *pdev)
this->read_buf = ams_delta_read_buf;
this->cmd_ctrl = ams_delta_hwcontrol;

- gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN);
- if (IS_ERR(gpiod_rdy)) {
- err = PTR_ERR(gpiod_rdy);
+ 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 out_mtd;
}

- if (gpiod_rdy)
+ if (priv->gpiod_rdy)
this->dev_ready = ams_delta_nand_ready;

/* 25 us command delay time */
@@ -202,66 +217,64 @@ static int ams_delta_init(struct platform_device *pdev)
this->ecc.mode = NAND_ECC_SOFT;
this->ecc.algo = NAND_ECC_HAMMING;

- platform_set_drvdata(pdev, io_base);
+ platform_set_drvdata(pdev, priv);

/* Set chip enabled, but */
- gpiod_nwp = devm_gpiod_get(&pdev->dev, "nwp", GPIOD_OUT_HIGH);
- if (IS_ERR(gpiod_nwp)) {
- err = PTR_ERR(gpiod_nwp);
+ priv->gpiod_nwp = devm_gpiod_get(&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);
goto out_mtd;
}

- gpiod_nce = devm_gpiod_get(&pdev->dev, "nce", GPIOD_OUT_HIGH);
- if (IS_ERR(gpiod_nce)) {
- err = PTR_ERR(gpiod_nce);
+ 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 out_mtd;
}

- gpiod_nre = devm_gpiod_get(&pdev->dev, "nre", GPIOD_OUT_HIGH);
- if (IS_ERR(gpiod_nre)) {
- err = PTR_ERR(gpiod_nre);
+ 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 out_mtd;
}

- gpiod_nwe = devm_gpiod_get(&pdev->dev, "nwe", GPIOD_OUT_HIGH);
- if (IS_ERR(gpiod_nwe)) {
- err = PTR_ERR(gpiod_nwe);
+ 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 out_mtd;
}

- gpiod_ale = devm_gpiod_get(&pdev->dev, "ale", GPIOD_OUT_LOW);
- if (IS_ERR(gpiod_ale)) {
- err = PTR_ERR(gpiod_ale);
+ 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 out_mtd;
}

- gpiod_cle = devm_gpiod_get(&pdev->dev, "cle", GPIOD_OUT_LOW);
- if (IS_ERR(gpiod_cle)) {
- err = PTR_ERR(gpiod_cle);
+ 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 out_mtd;
}

/* Scan to find existence of the device */
- err = nand_scan(ams_delta_mtd, 1);
+ err = nand_scan(mtd, 1);
if (err)
goto out_mtd;

/* Register the partitions */
- mtd_device_register(ams_delta_mtd, partition_info,
- ARRAY_SIZE(partition_info));
+ mtd_device_register(mtd, partition_info, ARRAY_SIZE(partition_info));

goto out;

out_mtd:
iounmap(io_base);
out_free:
- kfree(this);
out:
return err;
}
@@ -271,16 +284,15 @@ static int ams_delta_init(struct platform_device *pdev)
*/
static int ams_delta_cleanup(struct platform_device *pdev)
{
- void __iomem *io_base = platform_get_drvdata(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 */
- nand_release(ams_delta_mtd);
+ nand_release(mtd);

iounmap(io_base);

- /* Free the MTD device structure */
- kfree(mtd_to_nand(ams_delta_mtd));
-
return 0;
}

--
2.16.4