usb: musb: cppi41: allow to defer probing if DMA isn't yet available
If everything (musb, cppi41, phy) is built-in then musb will start
without the dma engine printing only
|musb-hdrc musb-hdrc.0.auto: Falied to request rx1.
The reason for this is that the musb device structs are created & probed
before those of the cppi41 device. So the cppi41 device is probed too
late.
As a workaround for this allow the musb_cppi41 part to defer the probe
if everything is fine except for the missing DMA controller. In case of
another error we continue.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/musb/musb_cppi41.c b/drivers/usb/musb/musb_cppi41.c
index ae95974..ff9d6de 100644
--- a/drivers/usb/musb/musb_cppi41.c
+++ b/drivers/usb/musb/musb_cppi41.c
@@ -484,6 +484,7 @@
if (ret)
goto err;
+ ret = -EINVAL;
if (port > MUSB_DMA_NUM_CHANNELS || !port)
goto err;
if (is_tx)
@@ -503,6 +504,7 @@
dc = dma_request_slave_channel(dev, str);
if (!dc) {
dev_err(dev, "Falied to request %s.\n", str);
+ ret = -EPROBE_DEFER;
goto err;
}
cppi41_channel->dc = dc;
@@ -510,7 +512,7 @@
return 0;
err:
cppi41_release_all_dma_chans(controller);
- return -EINVAL;
+ return ret;
}
void dma_controller_destroy(struct dma_controller *c)
@@ -526,7 +528,7 @@
void __iomem *base)
{
struct cppi41_dma_controller *controller;
- int ret;
+ int ret = 0;
if (!musb->controller->of_node) {
dev_err(musb->controller, "Need DT for the DMA engine.\n");
@@ -553,5 +555,7 @@
plat_get_fail:
kfree(controller);
kzalloc_fail:
+ if (ret == -EPROBE_DEFER)
+ return ERR_PTR(ret);
return NULL;
}