| Message ID | 20161014193113.29275-1-ralf@ramses-pyramidenbau.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Ralf, (Cc i2c) On Fri, Oct 14, 2016 at 9:31 PM, Ralf Ramsauer <ralf@ramses-pyramidenbau.de> wrote: > Instantiated SPI device nodes are marked with OF_POPULATE. This was > introduced in bd6c164. On unloading, loaded device nodes will of course > be unmarked. The problem are nodes the fail during initialisation: If a > node failed during registration, it won't be unloaded and hence never be > unmarked again. > > So if a SPI driver module is unloaded and reloaded, it will skip nodes > that failed before. > > Skip device nodes that are already populated and mark them only in case > of success. > > Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") > Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> > Cc: Geert Uytterhoeven <geert+renesas@glider.be> > --- > Hi, > > imagine the following situation: you loaded a spi driver as module, but > it fails to instantiate, because of some reasons (e.g. some resources, > like gpios, might be in use in userspace). > > When reloading the driver, _all_ nodes, including previously failed > ones, should be probed again. This is not the case at the moment. > Current behaviour only re-registers nodes that were previously > successfully loaded. > > This small patches fixes this behaviour. I stumbled over this while > working on a spi driver. Thanks for your patch! > drivers/spi/spi.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > index 200ca22..f96a04e 100644 > --- a/drivers/spi/spi.c > +++ b/drivers/spi/spi.c > @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) > return; > > for_each_available_child_of_node(master->dev.of_node, nc) { > - if (of_node_test_and_set_flag(nc, OF_POPULATED)) > + if (of_node_check_flag(nc, OF_POPULATED)) > continue; > spi = of_register_spi_device(master, nc); > - if (IS_ERR(spi)) > + if (IS_ERR(spi)) { > dev_warn(&master->dev, "Failed to create SPI device for %s\n", > nc->full_name); > + continue; > + } > + of_node_set_flag(nc, OF_POPULATED); I think it's safer to keep the atomic test-and-set, but clear the flag on failure, cfr. of_platform_device_create_pdata() and of_amba_device_create(). Shouldn't of_spi_notify() be fixed, too? The same issue exists for i2c in of_i2c_register_devices() and of_i2c_notify(), which is what I had used as an example. 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 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sun, Oct 16, 2016 at 10:49:11AM +0200, Geert Uytterhoeven wrote: > Hi Ralf, > > (Cc i2c) Thanks for letting me know! Adding Pantelis to CC, as he is the original author of OF_DYNAMIC. Please keep me in the loop. > > On Fri, Oct 14, 2016 at 9:31 PM, Ralf Ramsauer > <ralf@ramses-pyramidenbau.de> wrote: > > Instantiated SPI device nodes are marked with OF_POPULATE. This was > > introduced in bd6c164. On unloading, loaded device nodes will of course > > be unmarked. The problem are nodes the fail during initialisation: If a > > node failed during registration, it won't be unloaded and hence never be > > unmarked again. > > > > So if a SPI driver module is unloaded and reloaded, it will skip nodes > > that failed before. > > > > Skip device nodes that are already populated and mark them only in case > > of success. > > > > Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") > > Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> > > Cc: Geert Uytterhoeven <geert+renesas@glider.be> > > --- > > Hi, > > > > imagine the following situation: you loaded a spi driver as module, but > > it fails to instantiate, because of some reasons (e.g. some resources, > > like gpios, might be in use in userspace). > > > > When reloading the driver, _all_ nodes, including previously failed > > ones, should be probed again. This is not the case at the moment. > > Current behaviour only re-registers nodes that were previously > > successfully loaded. > > > > This small patches fixes this behaviour. I stumbled over this while > > working on a spi driver. > > Thanks for your patch! > > > drivers/spi/spi.c | 7 +++++-- > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > > index 200ca22..f96a04e 100644 > > --- a/drivers/spi/spi.c > > +++ b/drivers/spi/spi.c > > @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) > > return; > > > > for_each_available_child_of_node(master->dev.of_node, nc) { > > - if (of_node_test_and_set_flag(nc, OF_POPULATED)) > > + if (of_node_check_flag(nc, OF_POPULATED)) > > continue; > > spi = of_register_spi_device(master, nc); > > - if (IS_ERR(spi)) > > + if (IS_ERR(spi)) { > > dev_warn(&master->dev, "Failed to create SPI device for %s\n", > > nc->full_name); > > + continue; > > + } > > + of_node_set_flag(nc, OF_POPULATED); > > I think it's safer to keep the atomic test-and-set, but clear the flag on > failure, cfr. of_platform_device_create_pdata() and of_amba_device_create(). > > Shouldn't of_spi_notify() be fixed, too? > > The same issue exists for i2c in of_i2c_register_devices() and of_i2c_notify(), > which is what I had used as an example. > > 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
Hi Geert, On 10/16/2016 10:49 AM, Geert Uytterhoeven wrote: > Hi Ralf, > > (Cc i2c) > > On Fri, Oct 14, 2016 at 9:31 PM, Ralf Ramsauer > <ralf@ramses-pyramidenbau.de> wrote: >> Instantiated SPI device nodes are marked with OF_POPULATE. This was >> introduced in bd6c164. On unloading, loaded device nodes will of course >> be unmarked. The problem are nodes the fail during initialisation: If a >> node failed during registration, it won't be unloaded and hence never be >> unmarked again. >> >> So if a SPI driver module is unloaded and reloaded, it will skip nodes >> that failed before. >> >> Skip device nodes that are already populated and mark them only in case >> of success. >> >> Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") >> Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> >> Cc: Geert Uytterhoeven <geert+renesas@glider.be> >> --- >> Hi, >> >> imagine the following situation: you loaded a spi driver as module, but >> it fails to instantiate, because of some reasons (e.g. some resources, >> like gpios, might be in use in userspace). >> >> When reloading the driver, _all_ nodes, including previously failed >> ones, should be probed again. This is not the case at the moment. >> Current behaviour only re-registers nodes that were previously >> successfully loaded. >> >> This small patches fixes this behaviour. I stumbled over this while >> working on a spi driver. > > Thanks for your patch! > >> drivers/spi/spi.c | 7 +++++-- >> 1 file changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c >> index 200ca22..f96a04e 100644 >> --- a/drivers/spi/spi.c >> +++ b/drivers/spi/spi.c >> @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) >> return; >> >> for_each_available_child_of_node(master->dev.of_node, nc) { >> - if (of_node_test_and_set_flag(nc, OF_POPULATED)) >> + if (of_node_check_flag(nc, OF_POPULATED)) >> continue; >> spi = of_register_spi_device(master, nc); >> - if (IS_ERR(spi)) >> + if (IS_ERR(spi)) { >> dev_warn(&master->dev, "Failed to create SPI device for %s\n", >> nc->full_name); >> + continue; >> + } >> + of_node_set_flag(nc, OF_POPULATED); > > I think it's safer to keep the atomic test-and-set, but clear the flag on > failure, cfr. of_platform_device_create_pdata() and of_amba_device_create(). Ack, no prob. Let me change this in the next version. > > Shouldn't of_spi_notify() be fixed, too? Right, that's almost the same path. > > The same issue exists for i2c in of_i2c_register_devices() and of_i2c_notify(), > which is what I had used as an example. Good old c&p ;-) I'll fix and test that tomorrow and come back with two patches, as it touches different subsystems. Best Ralf > > 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 >
Hi Ralf, > On Oct 16, 2016, at 12:55 , Ralf Ramsauer <ralf@ramses-pyramidenbau.de> wrote: > > Hi Geert, > > On 10/16/2016 10:49 AM, Geert Uytterhoeven wrote: >> Hi Ralf, >> >> (Cc i2c) >> >> On Fri, Oct 14, 2016 at 9:31 PM, Ralf Ramsauer >> <ralf@ramses-pyramidenbau.de> wrote: >>> Instantiated SPI device nodes are marked with OF_POPULATE. This was >>> introduced in bd6c164. On unloading, loaded device nodes will of course >>> be unmarked. The problem are nodes the fail during initialisation: If a >>> node failed during registration, it won't be unloaded and hence never be >>> unmarked again. >>> >>> So if a SPI driver module is unloaded and reloaded, it will skip nodes >>> that failed before. >>> >>> Skip device nodes that are already populated and mark them only in case >>> of success. >>> >>> Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") >>> Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> >>> Cc: Geert Uytterhoeven <geert+renesas@glider.be> >>> --- >>> Hi, >>> >>> imagine the following situation: you loaded a spi driver as module, but >>> it fails to instantiate, because of some reasons (e.g. some resources, >>> like gpios, might be in use in userspace). >>> >>> When reloading the driver, _all_ nodes, including previously failed >>> ones, should be probed again. This is not the case at the moment. >>> Current behaviour only re-registers nodes that were previously >>> successfully loaded. >>> >>> This small patches fixes this behaviour. I stumbled over this while >>> working on a spi driver. >> >> Thanks for your patch! >> >>> drivers/spi/spi.c | 7 +++++-- >>> 1 file changed, 5 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c >>> index 200ca22..f96a04e 100644 >>> --- a/drivers/spi/spi.c >>> +++ b/drivers/spi/spi.c >>> @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) >>> return; >>> >>> for_each_available_child_of_node(master->dev.of_node, nc) { >>> - if (of_node_test_and_set_flag(nc, OF_POPULATED)) >>> + if (of_node_check_flag(nc, OF_POPULATED)) >>> continue; >>> spi = of_register_spi_device(master, nc); >>> - if (IS_ERR(spi)) >>> + if (IS_ERR(spi)) { >>> dev_warn(&master->dev, "Failed to create SPI device for %s\n", >>> nc->full_name); >>> + continue; >>> + } >>> + of_node_set_flag(nc, OF_POPULATED); >> >> I think it's safer to keep the atomic test-and-set, but clear the flag on >> failure, cfr. of_platform_device_create_pdata() and of_amba_device_create(). > Ack, no prob. Let me change this in the next version. >> >> Shouldn't of_spi_notify() be fixed, too? > Right, that's almost the same path. >> >> The same issue exists for i2c in of_i2c_register_devices() and of_i2c_notify(), >> which is what I had used as an example. > Good old c&p ;-) > I'll fix and test that tomorrow and come back with two patches, as it > touches different subsystems. > Thanks for this. This is a very rare case that’s easy to slip through. It is good to be consistent :) > Best > Ralf >> Regards — Pantelis >> 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 >> > > > -- > Ralf Ramsauer > GPG: 0x8F10049B -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Oct 17, 2016 at 10:20:47PM +0300, Pantelis Antoniou wrote: > Hi Ralf, > > > On Oct 16, 2016, at 12:55 , Ralf Ramsauer <ralf@ramses-pyramidenbau.de> wrote: > > > > Hi Geert, > > > > On 10/16/2016 10:49 AM, Geert Uytterhoeven wrote: > >> Hi Ralf, > >> > >> (Cc i2c) > >> > >> On Fri, Oct 14, 2016 at 9:31 PM, Ralf Ramsauer > >> <ralf@ramses-pyramidenbau.de> wrote: > >>> Instantiated SPI device nodes are marked with OF_POPULATE. This was > >>> introduced in bd6c164. On unloading, loaded device nodes will of course > >>> be unmarked. The problem are nodes the fail during initialisation: If a > >>> node failed during registration, it won't be unloaded and hence never be > >>> unmarked again. > >>> > >>> So if a SPI driver module is unloaded and reloaded, it will skip nodes > >>> that failed before. > >>> > >>> Skip device nodes that are already populated and mark them only in case > >>> of success. > >>> > >>> Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") > >>> Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> > >>> Cc: Geert Uytterhoeven <geert+renesas@glider.be> > >>> --- > >>> Hi, > >>> > >>> imagine the following situation: you loaded a spi driver as module, but > >>> it fails to instantiate, because of some reasons (e.g. some resources, > >>> like gpios, might be in use in userspace). > >>> > >>> When reloading the driver, _all_ nodes, including previously failed > >>> ones, should be probed again. This is not the case at the moment. > >>> Current behaviour only re-registers nodes that were previously > >>> successfully loaded. > >>> > >>> This small patches fixes this behaviour. I stumbled over this while > >>> working on a spi driver. > >> > >> Thanks for your patch! > >> > >>> drivers/spi/spi.c | 7 +++++-- > >>> 1 file changed, 5 insertions(+), 2 deletions(-) > >>> > >>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > >>> index 200ca22..f96a04e 100644 > >>> --- a/drivers/spi/spi.c > >>> +++ b/drivers/spi/spi.c > >>> @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) > >>> return; > >>> > >>> for_each_available_child_of_node(master->dev.of_node, nc) { > >>> - if (of_node_test_and_set_flag(nc, OF_POPULATED)) > >>> + if (of_node_check_flag(nc, OF_POPULATED)) > >>> continue; > >>> spi = of_register_spi_device(master, nc); > >>> - if (IS_ERR(spi)) > >>> + if (IS_ERR(spi)) { > >>> dev_warn(&master->dev, "Failed to create SPI device for %s\n", > >>> nc->full_name); > >>> + continue; > >>> + } > >>> + of_node_set_flag(nc, OF_POPULATED); > >> > >> I think it's safer to keep the atomic test-and-set, but clear the flag on > >> failure, cfr. of_platform_device_create_pdata() and of_amba_device_create(). > > Ack, no prob. Let me change this in the next version. > >> > Thanks for this. This is a very rare case that’s easy to slip through. > It is good to be consistent :) I read this as acked-by for the series?
> > Thanks for this. This is a very rare case that’s easy to slip through. > > It is good to be consistent :) > > I read this as acked-by for the series? Ah, I mixed up. You acked V2 :)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 200ca22..f96a04e 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1604,12 +1604,15 @@ static void of_register_spi_devices(struct spi_master *master) return; for_each_available_child_of_node(master->dev.of_node, nc) { - if (of_node_test_and_set_flag(nc, OF_POPULATED)) + if (of_node_check_flag(nc, OF_POPULATED)) continue; spi = of_register_spi_device(master, nc); - if (IS_ERR(spi)) + if (IS_ERR(spi)) { dev_warn(&master->dev, "Failed to create SPI device for %s\n", nc->full_name); + continue; + } + of_node_set_flag(nc, OF_POPULATED); } } #else
Instantiated SPI device nodes are marked with OF_POPULATE. This was introduced in bd6c164. On unloading, loaded device nodes will of course be unmarked. The problem are nodes the fail during initialisation: If a node failed during registration, it won't be unloaded and hence never be unmarked again. So if a SPI driver module is unloaded and reloaded, it will skip nodes that failed before. Skip device nodes that are already populated and mark them only in case of success. Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> Cc: Geert Uytterhoeven <geert+renesas@glider.be> --- Hi, imagine the following situation: you loaded a spi driver as module, but it fails to instantiate, because of some reasons (e.g. some resources, like gpios, might be in use in userspace). When reloading the driver, _all_ nodes, including previously failed ones, should be probed again. This is not the case at the moment. Current behaviour only re-registers nodes that were previously successfully loaded. This small patches fixes this behaviour. I stumbled over this while working on a spi driver. Ralf drivers/spi/spi.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)