Re: [PATCH v3 3/3] memory: Add Broadcom STB memory controller driver

From: Florian Fainelli
Date: Fri Aug 12 2022 - 13:53:02 EST


On 8/12/22 10:36, Krzysztof Kozlowski wrote:
On 12/08/2022 20:29, Florian Fainelli wrote:
On 8/9/22 02:58, Krzysztof Kozlowski wrote:
On 02/08/2022 01:09, Florian Fainelli wrote:
Add support for configuring the Self Refresh Power Down (SRPD)
inactivity timeout on Broadcom STB chips. This is used to conserve power
when the DRAM activity is reduced.



+static int __maybe_unused brcmstb_memc_resume(struct device *dev)
+{
+ struct brcmstb_memc *memc = dev_get_drvdata(dev);
+
+ if (memc->timeout_cycles == 0)
+ return 0;
+
+ return brcmstb_memc_srpd_config(memc, memc->timeout_cycles);
+}
+
+static SIMPLE_DEV_PM_OPS(brcmstb_memc_pm_ops, brcmstb_memc_suspend,
+ brcmstb_memc_resume);
+
+static struct platform_driver brcmstb_memc_driver = {
+ .probe = brcmstb_memc_probe,
+ .remove = brcmstb_memc_remove,
+ .driver = {
+ .name = "brcmstb_memc",
+ .owner = THIS_MODULE,

No need, run coccinelle.

+ .of_match_table = brcmstb_memc_of_match,
+ .pm = &brcmstb_memc_pm_ops,

Shouldn't this be pm_ptr()? and then no need for __maybe_unused in
brcmstb_memc_resume/suspend.

How can one can remove __maybe_unused without causing a warning for the
CONFIG_PM=n case, not that I needed to build to convince myself, but
still did anyway:

drivers/memory/brcmstb_memc.c:275:12: warning: 'brcmstb_memc_resume'
defined but not used [-Wunused-function]
static int brcmstb_memc_resume(struct device *dev)
^~~~~~~~~~~~~~~~~~~
drivers/memory/brcmstb_memc.c:252:12: warning: 'brcmstb_memc_suspend'
defined but not used [-Wunused-function]
static int brcmstb_memc_suspend(struct device *dev)
^~~~~~~~~~~~~~~~~~~~

unless you also implied enclosing those functions under an #if
IS_ENABLED(CONFIG_PM) or something which is IMHO less preferable.

Are you sure you added also pm_ptr()? I don't see such warnings with W=1
and final object does not have the functions (for a different driver but
same principle).

Yes I am sure I added pm_ptr() see the v4 I just submitted. I don't see how the compiler cannot warn about the functions being unused the day they stop being referenced by the pm_ops structure which is eliminated?
--
Florian