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rpi: use /proc/device-tree/compatible

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While some distributions have a modified /proc/cpuinfo including
the board revision for raspberry pi, most distributions don't
have this.

In order to guess the raspberry pi version in such cases, use
the /proc/device-tree/compatible content as a fallback solution.
The values expected from this file have been taken from
upstream kernel documentation:

Documentation/devicetree/bindings/arm/bcm/brcm,bcm2835.txt

Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>
This commit is contained in:
Cédric Bosdonnat
2017-02-22 09:55:11 +01:00
committed by Brendan Le Foll
parent b453f6633b
commit b20fe9163a
2 changed files with 51 additions and 0 deletions
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2
src/arm/arm.c
View File

@@ -87,6 +87,8 @@ mraa_arm_platform()
platform_type = MRAA_96BOARDS;
else if (mraa_file_contains("/proc/device-tree/model", "s900"))
platform_type = MRAA_96BOARDS;
else if (mraa_file_contains("/proc/device-tree/compatible", "raspberrypi,"))
platform_type = MRAA_RASPBERRY_PI;
}
switch (platform_type) {

49
src/arm/raspberry_pi.c
View File

@@ -219,10 +219,13 @@ mraa_raspberry_pi()
size_t len = 100;
char* line = calloc(len, sizeof(char));
mraa_boolean_t tweakedCpuinfo = 0;
FILE* fh = fopen("/proc/cpuinfo", "r");
if (fh != NULL) {
while (getline(&line, &len, fh) != -1) {
if (strncmp(line, "Revision", 8) == 0) {
tweakedCpuinfo = 1;
if (strstr(line, "0002") || strstr(line, "0003")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_B_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_B_REV_1;
@@ -267,6 +270,52 @@ mraa_raspberry_pi()
}
free(line);
// Some distros have a Revision line in /proc/cpuinfo for rpi.
// As this may not be the case for all distros, we need to find
// another way to guess the raspberry pi model.
if (!tweakedCpuinfo) {
// See Documentation/devicetree/bindings/arm/bcm/brcm,bcm2835.txt
// for the values
const char *compatible_path = "/proc/device-tree/compatible";
if (mraa_file_contains(compatible_path, "raspberrypi,model-b")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_B_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_B_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI_B_REV_1_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-b-rev2")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_B_REV_2;
platform_detected = PLATFORM_RASPBERRY_PI_B_REV_2;
b->phy_pin_count = MRAA_RASPBERRY_PI_AB_REV_2_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-zero")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_ZERO;
platform_detected = PLATFORM_RASPBERRY_PI_ZERO;
b->phy_pin_count = MRAA_RASPBERRY_PI_ZERO_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-a")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_A_REV_2;
platform_detected = PLATFORM_RASPBERRY_PI_A_REV_2;
b->phy_pin_count = MRAA_RASPBERRY_PI_AB_REV_2_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-b-plus")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_B_PLUS_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_B_PLUS_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI_AB_PLUS_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,compute-module")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_COMPUTE_MODULE_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_COMPUTE_MODULE_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI_COMPUTE_MODULE_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-a-plus")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_A_PLUS_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_A_PLUS_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI_AB_PLUS_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,2-model-b")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI2_B_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI2_B_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI2_B_REV_1_PINCOUNT;
} else if (mraa_file_contains(compatible_path, "raspberrypi,model-b")) {
b->platform_name = PLATFORM_NAME_RASPBERRY_PI_B_REV_1;
platform_detected = PLATFORM_RASPBERRY_PI_B_REV_1;
b->phy_pin_count = MRAA_RASPBERRY_PI_B_REV_1_PINCOUNT;
}
}
b->aio_count = 0;
b->adc_raw = 0;
b->adc_supported = 0;