| Message ID | cf8058db-03d2-4d47-bc39-2645c3d42e10@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [RFC,1/2] i2c: smbus: Prepare i2c_register_spd for usage on muxed segments | expand |
On 26.02.2024 11:36, Wolfram Sang wrote: > On Thu, Feb 22, 2024 at 11:25:43PM +0100, Heiner Kallweit wrote: >> Once the gpio mux driver binds to the "i2c-mux-gpio" platform device, >> this creates the i2c adapters for the muxed child segments. >> We can use the bus notifier mechanism to check for creation of the >> child i2d adapters, and call i2c_register_spd() for them. This allows >> to detect all DIMM's on systems with more than 8 memory slots. >> >> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > > Yay, this looks *much* better. Thanks for doing it! Sadly, I can also > only review, not test. Let's hope someone can step up to do the real > testing. Maybe resend it as RFT to lkml? > 3 weeks ago I sent the change as RFT to lkml, as suggested. However I didn't receive a single response yet. Now that 6.9-rc1 is out, we would have several weeks in linux-next before 6.10-rc1. Would it be ok for you to apply the patch and see whether we get any feedback from linux-next users? If yes, can you apply it as-is, or shall I resubmit the patch? > Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> >
> Now that 6.9-rc1 is out, we would have several weeks in linux-next > before 6.10-rc1. Would it be ok for you to apply the patch and see > whether we get any feedback from linux-next users? Yes, we can do that. > If yes, can you apply it as-is, or shall I resubmit the patch? This is a question for Andi who picks up driver patches meanwhile.
On 25.03.2024 18:36, Wolfram Sang wrote: > >> Now that 6.9-rc1 is out, we would have several weeks in linux-next >> before 6.10-rc1. Would it be ok for you to apply the patch and see >> whether we get any feedback from linux-next users? > > Yes, we can do that. > >> If yes, can you apply it as-is, or shall I resubmit the patch? > > This is a question for Andi who picks up driver patches meanwhile. > I have to rebase the patch anyway, so I'll resubmit.
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 8f225cd7b..4b9d04f20 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -105,6 +105,7 @@ #include <linux/ioport.h> #include <linux/init.h> #include <linux/i2c.h> +#include <linux/i2c-mux.h> #include <linux/i2c-smbus.h> #include <linux/acpi.h> #include <linux/io.h> @@ -291,6 +292,7 @@ struct i801_priv { #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI struct platform_device *mux_pdev; struct gpiod_lookup_table *lookup; + struct notifier_block mux_notifier_block; #endif struct platform_device *tco_pdev; @@ -1388,6 +1390,23 @@ static const struct dmi_system_id mux_dmi_table[] = { { } }; +static int i801_notifier_call(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct i801_priv *priv = container_of(nb, struct i801_priv, mux_notifier_block); + struct device *dev = data; + + if (action != BUS_NOTIFY_ADD_DEVICE || + dev->type != &i2c_adapter_type || + i2c_root_adapter(dev) != &priv->adapter) + return NOTIFY_DONE; + + /* Call i2c_register_spd for muxed child segments */ + i2c_register_spd(to_i2c_adapter(dev)); + + return NOTIFY_OK; +} + /* Setup multiplexing if needed */ static void i801_add_mux(struct i801_priv *priv) { @@ -1425,6 +1444,9 @@ static void i801_add_mux(struct i801_priv *priv) gpiod_add_lookup_table(lookup); priv->lookup = lookup; + priv->mux_notifier_block.notifier_call = i801_notifier_call; + if (bus_register_notifier(&i2c_bus_type, &priv->mux_notifier_block)) + return; /* * Register the mux device, we use PLATFORM_DEVID_NONE here * because since we are referring to the GPIO chip by name we are @@ -1443,6 +1465,7 @@ static void i801_add_mux(struct i801_priv *priv) static void i801_del_mux(struct i801_priv *priv) { + bus_unregister_notifier(&i2c_bus_type, &priv->mux_notifier_block); platform_device_unregister(priv->mux_pdev); gpiod_remove_lookup_table(priv->lookup); }
Once the gpio mux driver binds to the "i2c-mux-gpio" platform device, this creates the i2c adapters for the muxed child segments. We can use the bus notifier mechanism to check for creation of the child i2d adapters, and call i2c_register_spd() for them. This allows to detect all DIMM's on systems with more than 8 memory slots. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- drivers/i2c/busses/i2c-i801.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)