[PATCH v3] clkdev: Update clkdev id usage to allow for longer names

[PATCH v3] clkdev: Update clkdev id usage to allow for longer names

[Michael J. Ruhl]

clkdev DEV ID information is limited to an array of 20 bytes
(MAX_DEV_ID).  It is possible that the ID could be longer than
that.  If so, the lookup will fail because the "real ID" will
not match the copied value.

For instance, generating a device name for the I2C Designware
module using the PCI ID can result in a name of:

i2c_designware.39424

clkdev_create() will store:

i2c_designware.3942

The stored name is one off and will not match correctly during probe.

Increase the size of the ID to allow for a longer name.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
---

v2: Removed CON_ID update and added example to commit
V3: Add r-b and move version info

 drivers/clk/clkdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index ee37d0be6877..9cd80522ca2d 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -144,7 +144,7 @@ void clkdev_add_table(struct clk_lookup *cl, size_t num)
 	mutex_unlock(&clocks_mutex);
 }
 
-#define MAX_DEV_ID	20
+#define MAX_DEV_ID	24
 #define MAX_CON_ID	16
 
 struct clk_lookup_alloc {
-- 
2.41.0

Re: [PATCH v3] clkdev: Update clkdev id usage to allow for longer names

[Andy Shevchenko]

On Fri, Feb 23, 2024 at 03:25:56PM -0500, Michael J. Ruhl wrote:
> clkdev DEV ID information is limited to an array of 20 bytes
> (MAX_DEV_ID).  It is possible that the ID could be longer than
> that.  If so, the lookup will fail because the "real ID" will
> not match the copied value.
> 
> For instance, generating a device name for the I2C Designware
> module using the PCI ID can result in a name of:
> 
> i2c_designware.39424
> 
> clkdev_create() will store:
> 
> i2c_designware.3942
> 
> The stored name is one off and will not match correctly during probe.
> 
> Increase the size of the ID to allow for a longer name.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3] clkdev: Update clkdev id usage to allow for longer names

[Stephen Boyd]

Quoting Michael J. Ruhl (2024-02-23 12:25:56)
> clkdev DEV ID information is limited to an array of 20 bytes
> (MAX_DEV_ID).  It is possible that the ID could be longer than
> that.  If so, the lookup will fail because the "real ID" will
> not match the copied value.
> 
> For instance, generating a device name for the I2C Designware
> module using the PCI ID can result in a name of:
> 
> i2c_designware.39424
> 
> clkdev_create() will store:
> 
> i2c_designware.3942
> 
> The stored name is one off and will not match correctly during probe.
> 
> Increase the size of the ID to allow for a longer name.
> 
> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
> ---

Applied to clk-next