| Message ID | 20240815-const_dfc_prepare-v2-4-8316b87b8ff9@quicinc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | driver core: Prevent device_find_child() from modifying caller's match data | expand |
On Thu, Aug 15, 2024 at 10:58:05PM +0800, Zijun Hu wrote: > From: Zijun Hu <quic_zijuhu@quicinc.com> > > To prepare for constifying the following old driver core API: > > struct device *device_find_child(struct device *dev, void *data, > int (*match)(struct device *dev, void *data)); > to new: > struct device *device_find_child(struct device *dev, const void *data, > int (*match)(struct device *dev, const void *data)); > > The new API does not allow its match function (*match)() to modify > caller's match data @*data, but emac_sgmii_acpi_match() as the old > API's match function indeed modifies relevant match data, so it is not > suitable for the new API any more, fixed by implementing a equivalent > emac_device_find_child() instead of the old API usage. > > Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> > --- > drivers/net/ethernet/qualcomm/emac/emac-sgmii.c | 36 +++++++++++++++++++++++-- > 1 file changed, 34 insertions(+), 2 deletions(-) Can you rewrite this based on the cxl change to make it a bit more less of a "wrap the logic in yet another layer" type of change like this one is? thanks, greg k-h
On 2024/8/24 11:29, Greg Kroah-Hartman wrote: > On Thu, Aug 15, 2024 at 10:58:05PM +0800, Zijun Hu wrote: >> From: Zijun Hu <quic_zijuhu@quicinc.com> >> >> To prepare for constifying the following old driver core API: >> >> struct device *device_find_child(struct device *dev, void *data, >> int (*match)(struct device *dev, void *data)); >> to new: >> struct device *device_find_child(struct device *dev, const void *data, >> int (*match)(struct device *dev, const void *data)); >> >> The new API does not allow its match function (*match)() to modify >> caller's match data @*data, but emac_sgmii_acpi_match() as the old >> API's match function indeed modifies relevant match data, so it is not >> suitable for the new API any more, fixed by implementing a equivalent >> emac_device_find_child() instead of the old API usage. >> >> Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> >> --- >> drivers/net/ethernet/qualcomm/emac/emac-sgmii.c | 36 +++++++++++++++++++++++-- >> 1 file changed, 34 insertions(+), 2 deletions(-) > > Can you rewrite this based on the cxl change to make it a bit more less > of a "wrap the logic in yet another layer" type of change like this one > is? > sure. will do it today. > thanks, > > greg k-h
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c index e4bc18009d08..1c799be77d99 100644 --- a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c +++ b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c @@ -47,6 +47,38 @@ #define SERDES_START_WAIT_TIMES 100 +struct emac_dfc_data { + int (*match)(struct device *dev, void *data); + void *data; + struct device *target_device; +}; + +static int emac_dfc_match_modify(struct device *dev, void *data) +{ + struct emac_dfc_data *dfc_data = data; + int res; + + res = dfc_data->match(dev, dfc_data->data); + if (res && get_device(dev)) { + dfc_data->target_device = dev; + return res; + } + + return 0; +} + +/* I have the same function as device_find_child() but allow to modify + * caller's match data @*data. + */ +static struct device *emac_device_find_child(struct device *parent, void *data, + int (*match)(struct device *dev, void *data)) +{ + struct emac_dfc_data dfc_data = {match, data, NULL}; + + device_for_each_child(parent, &dfc_data, emac_dfc_match_modify); + return dfc_data.target_device; +} + int emac_sgmii_init(struct emac_adapter *adpt) { if (!(adpt->phy.sgmii_ops && adpt->phy.sgmii_ops->init)) @@ -358,8 +390,8 @@ int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt) if (has_acpi_companion(&pdev->dev)) { struct device *dev; - dev = device_find_child(&pdev->dev, &phy->sgmii_ops, - emac_sgmii_acpi_match); + dev = emac_device_find_child(&pdev->dev, &phy->sgmii_ops, + emac_sgmii_acpi_match); if (!dev) { dev_warn(&pdev->dev, "cannot find internal phy node\n");