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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2023-01-02 15:40:51 +0300
committerMiquel Raynal <miquel.raynal@bootlin.com>2023-01-07 17:19:40 +0300
commit718004a5972c83cbcc4b649ec34ff314de373650 (patch)
treec67ac5393b27b1e24f186c11db6e65d3cdd40de1 /drivers/mtd/nand
parent34569d869532b54d6e360d224a0254dcdd6a1785 (diff)
downloadlinux-718004a5972c83cbcc4b649ec34ff314de373650.tar.xz
mtd: rawnand: pasemi: Don't use static data to track per-device state
Up to now the pasemi nand driver only supported a single device instance. However the check for that was racy because two parallel calls of pasemi_nand_probe() could pass the check if (pasemi_nand_mtd) return -ENODEV; before any of them assigns a non-NULL value to it. So rework the driver to make use of per-device driver data. As an intended side effect the driver can bind more than one device and also gets rid of the check if (!pasemi_nand_mtd) return 0; in the remove callback that could only ever trigger after the above race happened. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/linux-mtd/20230102124051.1508424-1-u.kleine-koenig@pengutronix.de
Diffstat (limited to 'drivers/mtd/nand')
-rw-r--r--drivers/mtd/nand/raw/pasemi_nand.c63
1 files changed, 35 insertions, 28 deletions
diff --git a/drivers/mtd/nand/raw/pasemi_nand.c b/drivers/mtd/nand/raw/pasemi_nand.c
index c176036453ed..f7ef6ca06ca9 100644
--- a/drivers/mtd/nand/raw/pasemi_nand.c
+++ b/drivers/mtd/nand/raw/pasemi_nand.c
@@ -26,9 +26,12 @@
#define CLE_PIN_CTL 15
#define ALE_PIN_CTL 14
-static unsigned int lpcctl;
-static struct mtd_info *pasemi_nand_mtd;
-static struct nand_controller controller;
+struct pasemi_ddata {
+ struct nand_chip chip;
+ unsigned int lpcctl;
+ struct nand_controller controller;
+};
+
static const char driver_name[] = "pasemi-nand";
static void pasemi_read_buf(struct nand_chip *chip, u_char *buf, int len)
@@ -55,6 +58,8 @@ static void pasemi_write_buf(struct nand_chip *chip, const u_char *buf,
static void pasemi_hwcontrol(struct nand_chip *chip, int cmd,
unsigned int ctrl)
{
+ struct pasemi_ddata *ddata = container_of(chip, struct pasemi_ddata, chip);
+
if (cmd == NAND_CMD_NONE)
return;
@@ -65,12 +70,14 @@ static void pasemi_hwcontrol(struct nand_chip *chip, int cmd,
/* Push out posted writes */
eieio();
- inl(lpcctl);
+ inl(ddata->lpcctl);
}
static int pasemi_device_ready(struct nand_chip *chip)
{
- return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
+ struct pasemi_ddata *ddata = container_of(chip, struct pasemi_ddata, chip);
+
+ return !!(inl(ddata->lpcctl) & LBICTRL_LPCCTL_NR);
}
static int pasemi_attach_chip(struct nand_chip *chip)
@@ -93,29 +100,31 @@ static int pasemi_nand_probe(struct platform_device *ofdev)
struct device_node *np = dev->of_node;
struct resource res;
struct nand_chip *chip;
+ struct nand_controller *controller;
int err = 0;
+ struct pasemi_ddata *ddata;
+ struct mtd_info *pasemi_nand_mtd;
err = of_address_to_resource(np, 0, &res);
if (err)
return -EINVAL;
- /* We only support one device at the moment */
- if (pasemi_nand_mtd)
- return -ENODEV;
-
dev_dbg(dev, "pasemi_nand at %pR\n", &res);
/* Allocate memory for MTD device structure and private data */
- chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
- if (!chip) {
+ ddata = kzalloc(sizeof(*ddata), GFP_KERNEL);
+ if (!ddata) {
err = -ENOMEM;
goto out;
}
+ platform_set_drvdata(ofdev, ddata);
+ chip = &ddata->chip;
+ controller = &ddata->controller;
- controller.ops = &pasemi_ops;
- nand_controller_init(&controller);
- chip->controller = &controller;
+ controller->ops = &pasemi_ops;
+ nand_controller_init(controller);
+ chip->controller = controller;
pasemi_nand_mtd = nand_to_mtd(chip);
@@ -136,10 +145,10 @@ static int pasemi_nand_probe(struct platform_device *ofdev)
goto out_ior;
}
- lpcctl = pci_resource_start(pdev, 0);
+ ddata->lpcctl = pci_resource_start(pdev, 0);
pci_dev_put(pdev);
- if (!request_region(lpcctl, 4, driver_name)) {
+ if (!request_region(ddata->lpcctl, 4, driver_name)) {
err = -EBUSY;
goto out_ior;
}
@@ -172,45 +181,43 @@ static int pasemi_nand_probe(struct platform_device *ofdev)
}
dev_info(dev, "PA Semi NAND flash at %pR, control at I/O %x\n", &res,
- lpcctl);
+ ddata->lpcctl);
return 0;
out_cleanup_nand:
nand_cleanup(chip);
out_lpc:
- release_region(lpcctl, 4);
+ release_region(ddata->lpcctl, 4);
out_ior:
iounmap(chip->legacy.IO_ADDR_R);
out_mtd:
- kfree(chip);
+ kfree(ddata);
out:
return err;
}
static int pasemi_nand_remove(struct platform_device *ofdev)
{
- struct nand_chip *chip;
+ struct pasemi_ddata *ddata = platform_get_drvdata(ofdev);
+ struct mtd_info *pasemi_nand_mtd;
int ret;
+ struct nand_chip *chip;
- if (!pasemi_nand_mtd)
- return 0;
-
- chip = mtd_to_nand(pasemi_nand_mtd);
+ chip = &ddata->chip;
+ pasemi_nand_mtd = nand_to_mtd(chip);
/* Release resources, unregister device */
ret = mtd_device_unregister(pasemi_nand_mtd);
WARN_ON(ret);
nand_cleanup(chip);
- release_region(lpcctl, 4);
+ release_region(ddata->lpcctl, 4);
iounmap(chip->legacy.IO_ADDR_R);
/* Free the MTD device structure */
- kfree(chip);
-
- pasemi_nand_mtd = NULL;
+ kfree(ddata);
return 0;
}