Thanks for the suggestion, Peng.
On 11/26/2025 7:47 AM, Peng Fan wrote:
On Thu, Nov 20, 2025 at 08:29:11PM +0530, Tanmay Kathpalia wrote:
Thanks for your comment, Peng.
On 11/18/2025 10:39 AM, Peng Fan wrote:
On Mon, Nov 10, 2025 at 09:37:30AM -0800, Tanmay Kathpalia wrote:
Add reset control functionality to the SDHCI Cadence driver to properly
handle hardware reset sequences during probe. This ensures the controller
is in a known state before initialization.
Signed-off-by: Tanmay Kathpalia <[email protected]>
Reviewed-by: Balsundar Ponnusamy <[email protected]>
---
drivers/mmc/sdhci-cadence.c | 8 ++++++++
1 file changed, 8 insertions(+)
....
@@ -225,6 +227,12 @@ static int sdhci_cdns_probe(struct udevice *dev)
if (!plat->hrs_addr)
return -ENOMEM;
+ ret = reset_get_bulk(dev, &reset_bulk);
Should this be optional? Some in tree platforms may not have
the reset supported.
Yes, you're right-some in-tree platforms may not have reset support. In those
cases, the code will print a warning message ("Can't get reset") and continue
the probe process.
If you prefer, I can remove the warning and let the function fail silently
instead, or is there any other way you would suggest to make this optional?
devm_reset_bulk_get_optional() may help.
Regards
Peng
I looked into devm_reset_bulk_get_optional(), and I see that it
dynamically allocates the struct reset_ctl_bulk and adds it to the
device resources list if CONFIG_DEVRES is enabled. However, if
CONFIG_DEVRES is not enabled, we need to manually free the memory using
reset_release_bulk() in the driver's remove function. This means we
would need to store a pointer to struct reset_ctl_bulk in the driver's
private data, which would require additional changes to the
sdhci-cadence driver (since it currently uses the generic struct
sdhci_host with .priv_auto = sizeof(struct sdhci_host)).
Let me know if you’re okay with this approach, as it would require other
changes in the driver, or if you have any further recommendations.
Alternatively, I can simplify the implementation as shown below:
ret = reset_get_bulk(dev, &reset_bulk);
if (!ret)
reset_deassert_bulk(&reset_bulk);
Please let me know your preference.
Regards,
Tanmay
Regards
Peng
