[PATCH v2] USB: Use EHCI control transfer pid macros instead of constant values.

From: Dingyan Li
Date: Fri Mar 08 2024 - 22:38:02 EST


Macros with good names offer better readability. Besides, also move
the definition to ehci.h.

Signed-off-by: Dingyan Li <18500469033@xxxxxxx>
Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
V1 -> V2: Replacement in more places where Alan pointed out.

drivers/usb/host/ehci-dbg.c | 10 +++++-----
drivers/usb/host/ehci-q.c | 20 ++++++++------------
drivers/usb/host/ehci.h | 8 +++++++-
3 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/host/ehci-dbg.c b/drivers/usb/host/ehci-dbg.c
index c063fb042926..435001128221 100644
--- a/drivers/usb/host/ehci-dbg.c
+++ b/drivers/usb/host/ehci-dbg.c
@@ -430,13 +430,13 @@ static void qh_lines(struct ehci_hcd *ehci, struct ehci_qh *qh,
mark = '/';
}
switch ((scratch >> 8) & 0x03) {
- case 0:
+ case PID_CODE_OUT:
type = "out";
break;
- case 1:
+ case PID_CODE_IN:
type = "in";
break;
- case 2:
+ case PID_CODE_SETUP:
type = "setup";
break;
default:
@@ -602,10 +602,10 @@ static unsigned output_buf_tds_dir(char *buf, struct ehci_hcd *ehci,
list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
temp++;
switch ((hc32_to_cpu(ehci, qtd->hw_token) >> 8) & 0x03) {
- case 0:
+ case PID_CODE_OUT:
type = "out";
continue;
- case 1:
+ case PID_CODE_IN:
type = "in";
continue;
}
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 666f5c4db25a..ba37a9fcab92 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -27,10 +27,6 @@

/*-------------------------------------------------------------------------*/

-/* PID Codes that are used here, from EHCI specification, Table 3-16. */
-#define PID_CODE_IN 1
-#define PID_CODE_SETUP 2
-
/* fill a qtd, returning how much of the buffer we were able to queue up */

static unsigned int
@@ -230,7 +226,7 @@ static int qtd_copy_status (
/* fs/ls interrupt xfer missed the complete-split */
status = -EPROTO;
} else if (token & QTD_STS_DBE) {
- status = (QTD_PID (token) == 1) /* IN ? */
+ status = (QTD_PID(token) == PID_CODE_IN) /* IN ? */
? -ENOSR /* hc couldn't read data */
: -ECOMM; /* hc couldn't write data */
} else if (token & QTD_STS_XACT) {
@@ -606,7 +602,7 @@ qh_urb_transaction (
/* SETUP pid */
qtd_fill(ehci, qtd, urb->setup_dma,
sizeof (struct usb_ctrlrequest),
- token | (2 /* "setup" */ << 8), 8);
+ token | (PID_CODE_SETUP << 8), 8);

/* ... and always at least one more pid */
token ^= QTD_TOGGLE;
@@ -620,7 +616,7 @@ qh_urb_transaction (

/* for zero length DATA stages, STATUS is always IN */
if (len == 0)
- token |= (1 /* "in" */ << 8);
+ token |= (PID_CODE_IN << 8);
}

/*
@@ -642,7 +638,7 @@ qh_urb_transaction (
}

if (is_input)
- token |= (1 /* "in" */ << 8);
+ token |= (PID_CODE_IN << 8);
/* else it's already initted to "out" pid (0 << 8) */

maxpacket = usb_endpoint_maxp(&urb->ep->desc);
@@ -709,7 +705,7 @@ qh_urb_transaction (

if (usb_pipecontrol (urb->pipe)) {
one_more = 1;
- token ^= 0x0100; /* "in" <--> "out" */
+ token ^= (PID_CODE_IN << 8); /* "in" <--> "out" */
token |= QTD_TOGGLE; /* force DATA1 */
} else if (usb_pipeout(urb->pipe)
&& (urb->transfer_flags & URB_ZERO_PACKET)
@@ -1203,7 +1199,7 @@ static int ehci_submit_single_step_set_feature(
/* SETUP pid, and interrupt after SETUP completion */
qtd_fill(ehci, qtd, urb->setup_dma,
sizeof(struct usb_ctrlrequest),
- QTD_IOC | token | (2 /* "setup" */ << 8), 8);
+ QTD_IOC | token | (PID_CODE_SETUP << 8), 8);

submit_async(ehci, urb, &qtd_list, GFP_ATOMIC);
return 0; /*Return now; we shall come back after 15 seconds*/
@@ -1216,7 +1212,7 @@ static int ehci_submit_single_step_set_feature(
token ^= QTD_TOGGLE; /*We need to start IN with DATA-1 Pid-sequence*/
buf = urb->transfer_dma;

- token |= (1 /* "in" */ << 8); /*This is IN stage*/
+ token |= (PID_CODE_IN << 8); /*This is IN stage*/

maxpacket = usb_endpoint_maxp(&urb->ep->desc);

@@ -1229,7 +1225,7 @@ static int ehci_submit_single_step_set_feature(
qtd->hw_alt_next = EHCI_LIST_END(ehci);

/* STATUS stage for GetDesc control request */
- token ^= 0x0100; /* "in" <--> "out" */
+ token ^= (PID_CODE_IN << 8); /* "in" <--> "out" */
token |= QTD_TOGGLE; /* force DATA1 */

qtd_prev = qtd;
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 1441e3400796..d7a3c8d13f6b 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -321,10 +321,16 @@ struct ehci_qtd {
size_t length; /* length of buffer */
} __aligned(32);

+/* PID Codes that are used here, from EHCI specification, Table 3-16. */
+#define PID_CODE_OUT 0
+#define PID_CODE_IN 1
+#define PID_CODE_SETUP 2
+
/* mask NakCnt+T in qh->hw_alt_next */
#define QTD_MASK(ehci) cpu_to_hc32(ehci, ~0x1f)

-#define IS_SHORT_READ(token) (QTD_LENGTH(token) != 0 && QTD_PID(token) == 1)
+#define IS_SHORT_READ(token) (QTD_LENGTH(token) != 0 && \
+ QTD_PID(token) == PID_CODE_IN)

/*-------------------------------------------------------------------------*/

--
2.25.1