On 03/19/2015 08:55 PM, Tony Lindgren wrote:
--- a/drivers/usb/musb/musb_dsps.c
+++ b/drivers/usb/musb/musb_dsps.c
@@ -655,6 +655,36 @@ static int dsps_musb_reset(struct musb *musb)
return !session_restart;
}
+/* Similar to am35x, dm81xx support only 32-bit read operation */
+static void dsps_read_fifo32(struct musb_hw_ep *hw_ep, u16 len, u8 *dst)
+{
+ void __iomem *fifo = hw_ep->fifo;
+ u32 val;
+ int i;
+
+ /* Read for 32bit-aligned destination address */
+ if (likely((0x03 & (unsigned long)dst) == 0) && len >= 4) {
+ readsl(fifo, dst, len >> 2);
+ dst += len & ~0x03;
+ len &= 0x03;
+ }
+ /*
+ * Now read the remaining 1 to 3 byte or complete length if
+ * unaligned address.
+ */
This comment seems misplaced, it belongs before the next *if*.
+ if (len > 4) {
+ for (i = 0; i < (len >> 2); i++) {
+ *(u32 *)dst = musb_readl(fifo, 0);
+ dst += 4;
+ }
Not sure how this is different to using readsl().
Ah, the default implementation of musb_readl() uses __raw_readl().
So you'd probably want to keep this loop, not readsl() call.
Not sure I follow you here..
I just wrongly thought readsl() uses readl() internally. readl() is
supposed to swap bytes when needed (BE case), while __raw_readl() is not.
Also include/asm-generic/io.h readsl()
uses __raw_readl()?
Looking at the arch/arm/include/asm/io.h, readsl() is equivalent to
__raw_readsl() too. Forgot about this "asymmetry".
It seems things work with what I posted, so a readsl() loop, then
just read the remaining 1 to 3 bytes.
In LE mode, there would have been no difference anyway.
Regards,
Tony
WBR, Sergei
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html