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authorFabio Estevam <fabio.estevam@freescale.com>2015-01-13 20:14:15 -0200
committerBrian Norris <computersforpeace@gmail.com>2015-01-20 12:37:57 -0800
commitcfe4af3aac3bd63e9caf548157805ca46ad7b073 (patch)
tree8432c64db6f009425799a7e09c22b2321a1b12c9 /drivers/mtd
parentfcc87a95195236b0935183361a72e4a98bf577d8 (diff)
mtd: fsl-quadspi: Fix module unbound
When removing the fsl-quadspi module and running 'cat /proc/mtd' afterwards, we see garbage data like: $ rmmod fsl-quadspi $ cat /proc/mtd dev: size erasesize name mtd0: 00000000 00000000 "(null)" mtd0: 00000000 00000000 "(null)" mtd0: 00000000 00000000 "(null)" ... mtd0: a22296c6c756e28 00000000 "(null)" mtd0: a22296c6c756e28 3064746d "(null)" If we continue doing multiple module load/unload operations, then it will also lead to a kernel crash. The reason for this is due to the wrong mtd index used in mtd_device_unregister() in the remove function. We need to keep the mtd unregister index aligned with the one used in the probe function, which means we need to take into account the 'has_second_chip' property. By doing so we can guarantee that the mtd index is the same in the registration and unregistration functions. With this patch applied we can load/unload the fsl-quadspi driver several times and it will result in no crash. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Huang Shijie <shijie.huang@intel.com> Tested-by: Frank Li <Frank.Li@freescale.com> Acked-by: Allen Xu <han.xu@freescale.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/spi-nor/fsl-quadspi.c19
1 files changed, 13 insertions, 6 deletions
diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c
index 9d6080079a45..a46bea33580f 100644
--- a/drivers/mtd/spi-nor/fsl-quadspi.c
+++ b/drivers/mtd/spi-nor/fsl-quadspi.c
@@ -227,6 +227,7 @@ struct fsl_qspi {
u32 nor_num;
u32 clk_rate;
unsigned int chip_base_addr; /* We may support two chips. */
+ bool has_second_chip;
};
static inline int is_vybrid_qspi(struct fsl_qspi *q)
@@ -783,7 +784,6 @@ static int fsl_qspi_probe(struct platform_device *pdev)
struct spi_nor *nor;
struct mtd_info *mtd;
int ret, i = 0;
- bool has_second_chip = false;
const struct of_device_id *of_id =
of_match_device(fsl_qspi_dt_ids, &pdev->dev);
@@ -860,14 +860,14 @@ static int fsl_qspi_probe(struct platform_device *pdev)
goto irq_failed;
if (of_get_property(np, "fsl,qspi-has-second-chip", NULL))
- has_second_chip = true;
+ q->has_second_chip = true;
/* iterate the subnodes. */
for_each_available_child_of_node(dev->of_node, np) {
char modalias[40];
/* skip the holes */
- if (!has_second_chip)
+ if (!q->has_second_chip)
i *= 2;
nor = &q->nor[i];
@@ -943,9 +943,12 @@ static int fsl_qspi_probe(struct platform_device *pdev)
return 0;
last_init_failed:
- for (i = 0; i < q->nor_num; i++)
+ for (i = 0; i < q->nor_num; i++) {
+ /* skip the holes */
+ if (!q->has_second_chip)
+ i *= 2;
mtd_device_unregister(&q->mtd[i]);
-
+ }
irq_failed:
clk_disable_unprepare(q->clk);
clk_failed:
@@ -960,8 +963,12 @@ static int fsl_qspi_remove(struct platform_device *pdev)
struct fsl_qspi *q = platform_get_drvdata(pdev);
int i;
- for (i = 0; i < q->nor_num; i++)
+ for (i = 0; i < q->nor_num; i++) {
+ /* skip the holes */
+ if (!q->has_second_chip)
+ i *= 2;
mtd_device_unregister(&q->mtd[i]);
+ }
/* disable the hardware */
writel(QUADSPI_MCR_MDIS_MASK, q->iobase + QUADSPI_MCR);