Re: [RFC v1 PATCH 1/3] drivers: soc: add support for soc_device_match returning -EPROBE_DEFER
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2021-04-19 08:20:33
Also in:
dmaengine, dri-devel, linux-amlogic, linux-clk, linux-crypto, linux-gpio, linux-iommu, linux-media, linux-mediatek, linux-mmc, linux-omap, linux-phy, linux-pm, linux-renesas-soc, linux-staging, linux-usb, linux-watchdog, linuxppc-dev, lkml
Hi Alice, CC Arnd (soc_device_match() author) On Mon, Apr 19, 2021 at 6:28 AM Alice Guo (OSS) [off-list ref] wrote:
From: Alice Guo <redacted> In i.MX8M boards, the registration of SoC device is later than caam driver which needs it. Caam driver needs soc_device_match to provide -EPROBE_DEFER when no SoC device is registered and no early_soc_dev_attr.
I'm wondering if this is really a good idea: soc_device_match() is a last-resort low-level check, and IMHO should be made available early on, so there is no need for -EPROBE_DEFER.
Signed-off-by: Alice Guo <redacted>
Thanks for your patch!
quoted hunk ↗ jump to hunk
--- a/drivers/base/soc.c +++ b/drivers/base/soc.c@@ -110,6 +110,7 @@ static void soc_release(struct device *dev) } static struct soc_device_attribute *early_soc_dev_attr; +static bool soc_dev_attr_init_done = false;
Do you need this variable?
quoted hunk ↗ jump to hunk
struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr) {@@ -157,6 +158,7 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr return ERR_PTR(ret); } + soc_dev_attr_init_done = true; return soc_dev; out3:@@ -246,6 +248,9 @@ const struct soc_device_attribute *soc_device_match( if (!matches) return NULL; + if (!soc_dev_attr_init_done && !early_soc_dev_attr)
if (!soc_bus_type.p && !early_soc_dev_attr)
+ return ERR_PTR(-EPROBE_DEFER);
+
while (!ret) {
if (!(matches->machine || matches->family ||
matches->revision || matches->soc_id))
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds