Sakari Ailus <[email protected]> writes: > Hi Kevin, > > On Fri, Jun 09, 2017 at 09:10:26AM -0700, Kevin Hilman wrote: >> The davinci VPIF is a single hardware block, but the existing driver >> is broken up into a common library (vpif.c), output (vpif_display.c) and >> intput (vpif_capture.c). >> >> When migrating to DT, to better model the hardware, and because >> registers, interrupts, etc. are all common,it was decided to >> have a single VPIF hardware node[1]. >> >> Because davinci uses legacy, non-DT boot on several SoCs still, the >> platform_drivers need to remain. But they are also needed in DT boot. >> Since there are no DT nodes for the display/capture parts in DT >> boot (there is a single node for the parent/common device) we need to >> create platform_devices somewhere to instansiate the platform_drivers. >> >> When VPIF display/capture are needed for a DT boot, the VPIF node >> will have endpoints defined for its subdevs. Therefore, vpif_probe() >> checks for the presence of endpoints, and if detected manually creates >> the platform_devices for the display and capture platform_drivers. >> >> [1] Documentation/devicetree/bindings/media/ti,da850-vpif.txt >> >> Signed-off-by: Kevin Hilman <[email protected]> >> --- >> Changes since v1: >> - added proper error checking to kzalloc calls >> - rebased onto media/master >> >> drivers/media/platform/davinci/vpif.c | 57 >> ++++++++++++++++++++++++++++++++++- >> 1 file changed, 56 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/media/platform/davinci/vpif.c >> b/drivers/media/platform/davinci/vpif.c >> index 1b02a6363f77..c2d214dfaa3e 100644 >> --- a/drivers/media/platform/davinci/vpif.c >> +++ b/drivers/media/platform/davinci/vpif.c >> @@ -26,6 +26,7 @@ >> #include <linux/pm_runtime.h> >> #include <linux/spinlock.h> >> #include <linux/v4l2-dv-timings.h> >> +#include <linux/of_graph.h> >> >> #include "vpif.h" >> >> @@ -423,7 +424,9 @@ EXPORT_SYMBOL(vpif_channel_getfid); >> >> static int vpif_probe(struct platform_device *pdev) >> { >> - static struct resource *res; >> + static struct resource *res, *res_irq; >> + struct platform_device *pdev_capture, *pdev_display; >> + struct device_node *endpoint = NULL; >> >> res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> vpif_base = devm_ioremap_resource(&pdev->dev, res); >> @@ -435,6 +438,58 @@ static int vpif_probe(struct platform_device *pdev) >> >> spin_lock_init(&vpif_lock); >> dev_info(&pdev->dev, "vpif probe success\n"); >> + >> + /* >> + * If VPIF Node has endpoints, assume "new" DT support, >> + * where capture and display drivers don't have DT nodes >> + * so their devices need to be registered manually here >> + * for their legacy platform_drivers to work. >> + */ >> + endpoint = of_graph_get_next_endpoint(pdev->dev.of_node, >> + endpoint); >> + if (!endpoint) >> + return 0; >> + >> + /* >> + * For DT platforms, manually create platform_devices for >> + * capture/display drivers. >> + */ >> + res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); >> + if (!res_irq) { >> + dev_warn(&pdev->dev, "Missing IRQ resource.\n"); >> + return -EINVAL; >> + } >> + >> + pdev_capture = devm_kzalloc(&pdev->dev, sizeof(*pdev_capture), >> + GFP_KERNEL); >> + if (pdev_capture) { >> + pdev_capture->name = "vpif_capture"; >> + pdev_capture->id = -1; >> + pdev_capture->resource = res_irq; >> + pdev_capture->num_resources = 1; >> + pdev_capture->dev.dma_mask = pdev->dev.dma_mask; >> + pdev_capture->dev.coherent_dma_mask = >> pdev->dev.coherent_dma_mask; >> + pdev_capture->dev.parent = &pdev->dev; >> + platform_device_register(pdev_capture); > > Don't both of these (vpif_capture and vpif_display) depend on platform data? > Or do I miss something?
The driver can (continue to) work in legacy mode with platform_data. In that case, there is no VPIF DT node (or a node without endpoints). However, with recent changes, it can also work in DT mode, where the VPIF node and endpoints used for display/capture come from DT, in which case these nodes are created an don't depend on platform_data at all. Hope that clarifies things, and thanks for the review, Kevin
