On 23/06/25 10:44AM, Jonathan Cameron wrote:
On Tue, 17 Jun 2025 18:09:39 +0530 Neeraj Kumar <s.nee...@samsung.com> wrote:Add cxl_find_root_decoder to find root decoder on cxl bus. It is used to find root decoder during region creation Signed-off-by: Neeraj Kumar <s.nee...@samsung.com> --- drivers/cxl/core/port.c | 26 ++++++++++++++++++++++++++ drivers/cxl/cxl.h | 1 + 2 files changed, 27 insertions(+) diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 2452f7c15b2d..94d9322b8e38 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -513,6 +513,32 @@ struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev) } EXPORT_SYMBOL_NS_GPL(to_cxl_switch_decoder, "CXL"); +static int match_root_decoder(struct device *dev, void *data) +{ + return is_root_decoder(dev); +} + +/** + * cxl_find_root_decoder() - find a cxl root decoder on cxl bus + * @port: any descendant port in root-cxl-port topology + */ +struct cxl_root_decoder *cxl_find_root_decoder(struct cxl_port *port) +{ + struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port); + struct device *dev; + + if (!cxl_root) + return NULL; + + dev = device_find_child(&cxl_root->port.dev, NULL, match_root_decoder); +No blank line here. Generally when we have a call then an error check it is easier to see how they are related if we keep them in one block.
Thanks, Will fix it in V1
+ if (!dev) + return NULL; + + return to_cxl_root_decoder(dev); +} +EXPORT_SYMBOL_NS_GPL(cxl_find_root_decoder, "CXL"); + static void cxl_ep_release(struct cxl_ep *ep) { put_device(ep->ep); diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 30c80e04cb27..2c6a782d0941 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -871,6 +871,7 @@ bool is_cxl_nvdimm_bridge(struct device *dev); int devm_cxl_add_nvdimm(struct cxl_port *parent_port, struct cxl_memdev *cxlmd); struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_port *port); void cxl_region_discovery(struct cxl_port *port); +struct cxl_root_decoder *cxl_find_root_decoder(struct cxl_port *port); #ifdef CONFIG_CXL_REGION bool is_cxl_pmem_region(struct device *dev);
