kernel: support multiple transfers in single write to sysfs vme_data attribute

397a544b · Tomasz Wlostowski · bd29f2cb · 397a544b · 397a544b
Commit 397a544b authored Mar 05, 2014 by Tomasz Wlostowski
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Showing with 34 additions and 5 deletions

svec-sw.in doc/svec-sw.in +1 -0

svec-sysfs.c kernel/svec-sysfs.c +33 -5

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--- a/doc/svec-sw.in
+++ b/doc/svec-sw.in
@@ -313,6 +313,7 @@ Reading the @code{configured} file lets you check if the card has been already c
 @section Raw access to the VME registers
 This is handled via the @code{vme_addr} and @code{vme_data} attributes.
 In order to read something from a given address, put the address in @code{vme_addr} file and then read the @code{vme_data} file. Writes are done in the same way.
+If more than one value is written into @code{vme_data}, the driver will perform multiple transfers, incrementing the address by 32 bits at each transfer.

 @b{Note:} Raw VME access through @code{sysfs} works only if the VME register window is correctly configured.


--- a/kernel/svec-sysfs.c
+++ b/kernel/svec-sysfs.c
@@ -232,18 +232,46 @@ ATTR_SHOW_CALLBACK(vme_data)
 	return snprintf(buf, PAGE_SIZE, "0x%x\n", data);
 }

+static int __next_token(char **str, char *buf, int buf_length)
+{
+	char *p = *str, *tok;
+	int len;
+
+	while(isspace (*p))
+		p++;
+
+	if(*p == 0)
+		return 0;
+	tok = p;
+	while(*p && !isspace(*p))
+		p++;
+
+	len = min(p - tok + 1, buf_length - 1);
+	memcpy(buf, tok, len);
+	buf[len - 1] = 0;
+
+	*str = p;
+	return 1;
+}
+
 ATTR_STORE_CALLBACK(vme_data)
 {
-	uint32_t data;
 	struct svec_dev *card = dev_get_drvdata(pdev);
-
+	uint32_t data;
+	uint32_t addr = card->vme_raw_addr;
+	char *args = (char *) buf, token[16];
+	
 	if (!card->cfg_cur.configured)
 		return -EAGAIN;

-	if (sscanf(buf, "%i", &data) != 1)
-		return -EINVAL;
+	while (__next_token (&args, token, sizeof(token)))
+	{
+		if (sscanf(token, "%i", &data) != 1)
+			return -EINVAL;

-	iowrite32be(data, card->map[MAP_REG]->kernel_va + card->vme_raw_addr);
+		iowrite32be(data, card->map[MAP_REG]->kernel_va + addr);
+		addr += 4;
+	}

 	return count;
 }