[v6,1/2] mtd: fsl-quadspi: Distinguish the mtd device names

Message ID 1516285721-32294-1-git-send-email-fabio.estevam@nxp.com
State New
Delegated to: Cyrille Pitchen
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Series
  • [v6,1/2] mtd: fsl-quadspi: Distinguish the mtd device names
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Commit Message

Fabio Estevam Jan. 18, 2018, 2:28 p.m.
Currently on a imx6sx-sdb board, which has two SPI NOR chips connected
to QSPI2 the following output from /proc/mtd is seen:

# cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 01000000 00010000 "21e4000.qspi"
mtd1: 01000000 00010000 "21e4000.qspi"

Attempts to partition them on the kernel command line result in both
chips with identical (and identically named) partitions, which is
an inconvenient behavior.

Assign a different mtd->name for each mtd device to avoid this problem.

After this change the output from /proc/mtd becomes:

# cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 01000000 00010000 "21e4000.qspi-0"
mtd1: 01000000 00010000 "21e4000.qspi-1"

In order to keep mtdparts compatibility keep the mtd->name
unchanged when a single SPI NOR is present.

Reported-by: David Wolfe <david.wolfe@nxp.com>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
Changes since v5:
- Preserve the label value, if any. (Boris)

 drivers/mtd/spi-nor/fsl-quadspi.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Comments

Fabio Estevam Jan. 25, 2018, 10:20 a.m. | #1
Hi Boris,

On Thu, Jan 18, 2018 at 12:28 PM, Fabio Estevam <fabio.estevam@nxp.com> wrote:
> Currently on a imx6sx-sdb board, which has two SPI NOR chips connected
> to QSPI2 the following output from /proc/mtd is seen:
>
> # cat /proc/mtd
> dev:    size   erasesize  name
> mtd0: 01000000 00010000 "21e4000.qspi"
> mtd1: 01000000 00010000 "21e4000.qspi"
>
> Attempts to partition them on the kernel command line result in both
> chips with identical (and identically named) partitions, which is
> an inconvenient behavior.
>
> Assign a different mtd->name for each mtd device to avoid this problem.
>
> After this change the output from /proc/mtd becomes:
>
> # cat /proc/mtd
> dev:    size   erasesize  name
> mtd0: 01000000 00010000 "21e4000.qspi-0"
> mtd1: 01000000 00010000 "21e4000.qspi-1"
>
> In order to keep mtdparts compatibility keep the mtd->name
> unchanged when a single SPI NOR is present.
>
> Reported-by: David Wolfe <david.wolfe@nxp.com>
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
> Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
> Changes since v5:
> - Preserve the label value, if any. (Boris)

Do you plan to apply this one for 4.17?

Thanks
Boris Brezillon Jan. 25, 2018, 10:33 a.m. | #2
On Thu, 25 Jan 2018 08:20:59 -0200
Fabio Estevam <festevam@gmail.com> wrote:

> Hi Boris,
> 
> On Thu, Jan 18, 2018 at 12:28 PM, Fabio Estevam <fabio.estevam@nxp.com> wrote:
> > Currently on a imx6sx-sdb board, which has two SPI NOR chips connected
> > to QSPI2 the following output from /proc/mtd is seen:
> >
> > # cat /proc/mtd
> > dev:    size   erasesize  name
> > mtd0: 01000000 00010000 "21e4000.qspi"
> > mtd1: 01000000 00010000 "21e4000.qspi"
> >
> > Attempts to partition them on the kernel command line result in both
> > chips with identical (and identically named) partitions, which is
> > an inconvenient behavior.
> >
> > Assign a different mtd->name for each mtd device to avoid this problem.
> >
> > After this change the output from /proc/mtd becomes:
> >
> > # cat /proc/mtd
> > dev:    size   erasesize  name
> > mtd0: 01000000 00010000 "21e4000.qspi-0"
> > mtd1: 01000000 00010000 "21e4000.qspi-1"
> >
> > In order to keep mtdparts compatibility keep the mtd->name
> > unchanged when a single SPI NOR is present.
> >
> > Reported-by: David Wolfe <david.wolfe@nxp.com>
> > Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
> > Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> > ---
> > Changes since v5:
> > - Preserve the label value, if any. (Boris)  
> 
> Do you plan to apply this one for 4.17?

I'm not applying spi-nor patches, and Cyrille already sent me his PR
for 4.16. So yes, I'd say it will be queued for 4.17. Is this a problem?
Fabio Estevam Jan. 25, 2018, 10:40 a.m. | #3
Hi Boris,

On Thu, Jan 25, 2018 at 8:33 AM, Boris Brezillon
<boris.brezillon@free-electrons.com> wrote:

> I'm not applying spi-nor patches, and Cyrille already sent me his PR
> for 4.16. So yes, I'd say it will be queued for 4.17. Is this a problem?

No problem. Thanks for the clarification.

Cyrille, I missed to add you on Cc on v6. Should I resend it with you on Cc?

Thanks

Patch

diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c
index 2901c7b..1038842 100644
--- a/drivers/mtd/spi-nor/fsl-quadspi.c
+++ b/drivers/mtd/spi-nor/fsl-quadspi.c
@@ -1051,6 +1051,24 @@  static int fsl_qspi_probe(struct platform_device *pdev)
 		spi_nor_set_flash_node(nor, np);
 		nor->priv = q;
 
+		if (q->nor_num > 1 && !mtd->name) {
+			int spiflash_idx;
+
+			ret = of_property_read_u32(np, "reg", &spiflash_idx);
+			if (!ret) {
+				mtd->name = devm_kasprintf(dev, GFP_KERNEL,
+							   "%s-%d",
+							   dev_name(dev),
+							   spiflash_idx);
+				if (!mtd->name) {
+					ret = -ENOMEM;
+					goto mutex_failed;
+				}
+			} else {
+				dev_warn(dev, "reg property is missing\n");
+			}
+		}
+
 		/* fill the hooks */
 		nor->read_reg = fsl_qspi_read_reg;
 		nor->write_reg = fsl_qspi_write_reg;