Nico Huber merged this change.
linux_spi: Hardcode default spispeed of 2MHz
Leaving the `linux_spi` driver's unknown default is almost never what we
want and resulted in many support requests since Raspbian switched to a
default that is too high for most applications.
Change-Id: I9361b7c1a1ab8900a619b06e1dae14cd87eb56c2
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/30368
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
---
M linux_spi.c
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/linux_spi.c b/linux_spi.c
index 3e60492..711ab4a 100644
--- a/linux_spi.c
+++ b/linux_spi.c
@@ -18,6 +18,8 @@
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
+#include <stdint.h>
+#include <inttypes.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
@@ -66,7 +68,7 @@
int linux_spi_init(void)
{
char *p, *endp, *dev;
- uint32_t speed_hz = 0;
+ uint32_t speed_hz = 2 * 1000 * 1000;
/* FIXME: make the following configurable by CLI options. */
/* SPI mode 0 (beware this also includes: MSB first, CS active low and others */
const uint8_t mode = SPI_MODE_0;
@@ -75,11 +77,15 @@
p = extract_programmer_param("spispeed");
if (p && strlen(p)) {
speed_hz = (uint32_t)strtoul(p, &endp, 10) * 1000;
- if (p == endp) {
+ if (p == endp || speed_hz == 0) {
msg_perr("%s: invalid clock: %s kHz\n", __func__, p);
free(p);
return 1;
}
+ } else {
+ msg_pinfo("Using default %"PRIu32
+ "kHz clock. Use 'spispeed' parameter to override.\n",
+ speed_hz / 1000);
}
free(p);
@@ -104,15 +110,12 @@
return 1;
/* We rely on the shutdown function for cleanup from here on. */
- if (speed_hz > 0) {
- if (ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed_hz) == -1) {
- msg_perr("%s: failed to set speed to %d Hz: %s\n",
- __func__, speed_hz, strerror(errno));
- return 1;
- }
-
- msg_pdbg("Using %d kHz clock\n", speed_hz/1000);
+ if (ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed_hz) == -1) {
+ msg_perr("%s: failed to set speed to %"PRIu32"Hz: %s\n",
+ __func__, speed_hz, strerror(errno));
+ return 1;
}
+ msg_pdbg("Using %"PRIu32"kHz clock\n", speed_hz / 1000);
if (ioctl(fd, SPI_IOC_WR_MODE, &mode) == -1) {
msg_perr("%s: failed to set SPI mode to 0x%02x: %s\n",
To view, visit change 30368. To unsubscribe, or for help writing mail filters, visit settings.