diff options
| author | stefanct <stefanct@2b7e53f0-3cfb-0310-b3e9-8179ed1497e1> | 2013-01-03 20:44:30 +0000 |
|---|---|---|
| committer | stefanct <stefanct@2b7e53f0-3cfb-0310-b3e9-8179ed1497e1> | 2013-01-03 20:44:30 +0000 |
| commit | 56db1525df14792574a9847d22eaf1fea09a115e (patch) | |
| tree | 05451bdc93ffcab3935c6ac35f5f0dd480c9f012 /buspirate_spi.c | |
| parent | c6b6b55bb85fdf72a98310a4e3b7d7febbf344a1 (diff) | |
| download | flashrom-56db1525df14792574a9847d22eaf1fea09a115e.tar.gz | |
Add user interface to activate the Bus Pirate pull-up resistors.
When working with some flash chips using the Bus Pirate programmer, the
use of the Bus Pirate's on-board pull-up resistors is sometimes
necessary.
On v3 hardware the use of said pull-up resistors requires the user to apply a
voltage to the VPU pin of the Bus Pirate, and then command it to use them.
For v4 hardware which supports also fixed internal 3.3V and 5V sources no
documentation could be found.
Here is a link to information pertaining to what this patch does:
http://dangerousprototypes.com/docs/SPI_(binary)#0100wxyz_-_Configure_peripherals_w.3Dpower.2C_x.3Dpull-ups.2C_y.3DAUX.2C_z.3DCS
Bonus: small cleanup of superfluous stack variables.
Signed-off-by: Brian Salcedo <bsalcedo@gmx.us>
Signed-off-by: Stefan Tauner <stefan.tauner@student.tuwien.ac.at>
Tested-by: Brian Salcedo <bsalcedo@gmx.us>
Acked-by: Stefan Tauner <stefan.tauner@student.tuwien.ac.at>
git-svn-id: https://code.coreboot.org/svn/flashrom/trunk@1641 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Diffstat (limited to 'buspirate_spi.c')
| -rw-r--r-- | buspirate_spi.c | 37 |
1 files changed, 26 insertions, 11 deletions
diff --git a/buspirate_spi.c b/buspirate_spi.c index 55d4133..d2ebc75 100644 --- a/buspirate_spi.c +++ b/buspirate_spi.c @@ -201,14 +201,14 @@ out_shutdown: int buspirate_spi_init(void) { - char *dev = NULL; - char *speed = NULL; char *tmp; + char *dev; + int i; unsigned int fw_version_major = 0; unsigned int fw_version_minor = 0; int spispeed = 0x7; int ret = 0; - int i; + int pullup = 0; dev = extract_programmer_param("dev"); if (dev && !strlen(dev)) { @@ -220,18 +220,29 @@ int buspirate_spi_init(void) return 1; } - speed = extract_programmer_param("spispeed"); - if (speed) { - for (i = 0; spispeeds[i].name; i++) - if (!strncasecmp(spispeeds[i].name, speed, - strlen(spispeeds[i].name))) { + tmp = extract_programmer_param("spispeed"); + if (tmp) { + for (i = 0; spispeeds[i].name; i++) { + if (!strncasecmp(spispeeds[i].name, tmp, strlen(spispeeds[i].name))) { spispeed = spispeeds[i].speed; break; } + } if (!spispeeds[i].name) msg_perr("Invalid SPI speed, using default.\n"); } - free(speed); + free(tmp); + + tmp = extract_programmer_param("pullups"); + if (tmp) { + if (strcasecmp("on", tmp) == 0) + pullup = 1; + else if (strcasecmp("off", tmp) == 0) + ; // ignore + else + msg_perr("Invalid pullups state, not using them.\n"); + } + free(tmp); /* Default buffer size is 19: 16 bytes data, 3 bytes control. */ #define DEFAULT_BUFSIZE (16 + 3) @@ -395,12 +406,16 @@ int buspirate_spi_init(void) } /* Initial setup (SPI peripherals config): Enable power, CS high, AUX */ - bp_commbuf[0] = 0x40 | 0xb; + bp_commbuf[0] = 0x40 | 0x0b; + if (pullup == 1) { + bp_commbuf[0] |= (1 << 2); + msg_pdbg("Enabling pull-up resistors.\n"); + } ret = buspirate_sendrecv(bp_commbuf, 1, 1); if (ret) return 1; if (bp_commbuf[0] != 0x01) { - msg_perr("Protocol error while setting power/CS/AUX!\n"); + msg_perr("Protocol error while setting power/CS/AUX(/Pull-up resistors)!\n"); return 1; } |