| Message ID | 20120520060802.03CE73E03B8@localhost (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On 05/19/2012 11:08 PM, Grant Likely wrote: > On Sat, 19 May 2012 23:54:36 -0600, Grant Likely<grant.likely@secretlab.ca> wrote: >> On Fri, 11 May 2012 15:05:21 -0700, David Daney<ddaney.cavm@gmail.com> wrote: >>> From: David Daney<david.daney@cavium.com> >>> >>> When generating MODALIASes, it is convenient to add things like "spi:" >>> or "i2c:" to the front of the strings. This allows the standard >>> modprobe to find the right driver when automatically populating bus >>> children from the device tree structure. >>> >>> Add a prefix parameter, and adjust callers. For >>> of_register_spi_devices() use the "spi:" prefix. >>> >>> Signed-off-by: David Daney<david.daney@cavium.com> >> >> Applied, thanks. Some notes below... > > Wait... why is this necessary? Because in of_register_spi_devices() in of_spi.c, you do: request_module(spi->modalias); The string passed to request_module() must have the "spi:" prefix. > The module type prefix isn't stored in > the modalias value for any other bus type as far as I can see, It is only useful with the prefix, so I though I would add it to the stored value. > and > with this series it appears that the "spi:" prefix may or may not be > present in the modalias. That doesn't look right. Perhaps, but the with the combination of patches 1/3 and 2/3 I tried to ensure that the prefix would always be present for SPI devices. > > Why isn't prefixing spi: at uevent time sufficient? Because udev may not be loading the driver. > IIUC, modprobe > depends on either UEVENT or the modalias attribute to know which > driver to probe. It does look like the attribute is missing the spi: > prefix though. Does the following change work instead of these two > patches? > No. > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > index 3d8f662..da8aac7 100644 > --- a/drivers/spi/spi.c > +++ b/drivers/spi/spi.c > @@ -51,7 +51,7 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf) > { > const struct spi_device *spi = to_spi_device(dev); > > - return sprintf(buf, "%s\n", spi->modalias); > + return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); > } > > So, I've dropped this patch from my tree. If the change above works > for you then I'll push it out. > > g. >
On Tue, May 22, 2012 at 1:45 PM, David Daney <ddaney.cavm@gmail.com> wrote: > On 05/19/2012 11:08 PM, Grant Likely wrote: >> >> On Sat, 19 May 2012 23:54:36 -0600, Grant >> Likely<grant.likely@secretlab.ca> wrote: >>> >>> On Fri, 11 May 2012 15:05:21 -0700, David Daney<ddaney.cavm@gmail.com> >>> wrote: >>>> >>>> From: David Daney<david.daney@cavium.com> >>>> >>>> When generating MODALIASes, it is convenient to add things like "spi:" >>>> or "i2c:" to the front of the strings. This allows the standard >>>> modprobe to find the right driver when automatically populating bus >>>> children from the device tree structure. >>>> >>>> Add a prefix parameter, and adjust callers. For >>>> of_register_spi_devices() use the "spi:" prefix. >>>> >>>> Signed-off-by: David Daney<david.daney@cavium.com> >>> >>> >>> Applied, thanks. Some notes below... >> >> >> Wait... why is this necessary? > > > Because in of_register_spi_devices() in of_spi.c, you do: > > request_module(spi->modalias); > > The string passed to request_module() must have the "spi:" prefix. How about modifying the call to request_module() to include the prefix also? I think that would be a simpler change overall. Would that work? g.
On 05/22/2012 01:09 PM, Grant Likely wrote: > On Tue, May 22, 2012 at 1:45 PM, David Daney<ddaney.cavm@gmail.com> wrote: >> On 05/19/2012 11:08 PM, Grant Likely wrote: >>> >>> On Sat, 19 May 2012 23:54:36 -0600, Grant >>> Likely<grant.likely@secretlab.ca> wrote: >>>> >>>> On Fri, 11 May 2012 15:05:21 -0700, David Daney<ddaney.cavm@gmail.com> >>>> wrote: >>>>> >>>>> From: David Daney<david.daney@cavium.com> >>>>> >>>>> When generating MODALIASes, it is convenient to add things like "spi:" >>>>> or "i2c:" to the front of the strings. This allows the standard >>>>> modprobe to find the right driver when automatically populating bus >>>>> children from the device tree structure. >>>>> >>>>> Add a prefix parameter, and adjust callers. For >>>>> of_register_spi_devices() use the "spi:" prefix. >>>>> >>>>> Signed-off-by: David Daney<david.daney@cavium.com> >>>> >>>> >>>> Applied, thanks. Some notes below... >>> >>> >>> Wait... why is this necessary? >> >> >> Because in of_register_spi_devices() in of_spi.c, you do: >> >> request_module(spi->modalias); >> >> The string passed to request_module() must have the "spi:" prefix. > > How about modifying the call to request_module() to include the prefix > also? I think that would be a simpler change overall. Would that > work? It seems to. I just sent such a patch in a new thread. David Daney
Cool, thanks. g. On Tue, May 22, 2012 at 4:49 PM, David Daney <ddaney.cavm@gmail.com> wrote: > On 05/22/2012 01:09 PM, Grant Likely wrote: >> >> On Tue, May 22, 2012 at 1:45 PM, David Daney<ddaney.cavm@gmail.com> >> wrote: >>> >>> On 05/19/2012 11:08 PM, Grant Likely wrote: >>>> >>>> >>>> On Sat, 19 May 2012 23:54:36 -0600, Grant >>>> Likely<grant.likely@secretlab.ca> wrote: >>>>> >>>>> >>>>> On Fri, 11 May 2012 15:05:21 -0700, David Daney<ddaney.cavm@gmail.com> >>>>> wrote: >>>>>> >>>>>> >>>>>> From: David Daney<david.daney@cavium.com> >>>>>> >>>>>> When generating MODALIASes, it is convenient to add things like "spi:" >>>>>> or "i2c:" to the front of the strings. This allows the standard >>>>>> modprobe to find the right driver when automatically populating bus >>>>>> children from the device tree structure. >>>>>> >>>>>> Add a prefix parameter, and adjust callers. For >>>>>> of_register_spi_devices() use the "spi:" prefix. >>>>>> >>>>>> Signed-off-by: David Daney<david.daney@cavium.com> >>>>> >>>>> >>>>> >>>>> Applied, thanks. Some notes below... >>>> >>>> >>>> >>>> Wait... why is this necessary? >>> >>> >>> >>> Because in of_register_spi_devices() in of_spi.c, you do: >>> >>> request_module(spi->modalias); >>> >>> The string passed to request_module() must have the "spi:" prefix. >> >> >> How about modifying the call to request_module() to include the prefix >> also? I think that would be a simpler change overall. Would that >> work? > > > It seems to. I just sent such a patch in a new thread. > > David Daney
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 3d8f662..da8aac7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -51,7 +51,7 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf) { const struct spi_device *spi = to_spi_device(dev); - return sprintf(buf, "%s\n", spi->modalias); + return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); } So, I've dropped this patch from my tree. If the change above works